Sample records for abnormal visual system

  1. Anorexia nervosa and body dysmorphic disorder are associated with abnormalities in processing visual information.

    PubMed

    Li, W; Lai, T M; Bohon, C; Loo, S K; McCurdy, D; Strober, M; Bookheimer, S; Feusner, J

    2015-07-01

    Anorexia nervosa (AN) and body dysmorphic disorder (BDD) are characterized by distorted body image and are frequently co-morbid with each other, although their relationship remains little studied. While there is evidence of abnormalities in visual and visuospatial processing in both disorders, no study has directly compared the two. We used two complementary modalities--event-related potentials (ERPs) and functional magnetic resonance imaging (fMRI)--to test for abnormal activity associated with early visual signaling. We acquired fMRI and ERP data in separate sessions from 15 unmedicated individuals in each of three groups (weight-restored AN, BDD, and healthy controls) while they viewed images of faces and houses of different spatial frequencies. We used joint independent component analyses to compare activity in visual systems. AN and BDD groups demonstrated similar hypoactivity in early secondary visual processing regions and the dorsal visual stream when viewing low spatial frequency faces, linked to the N170 component, as well as in early secondary visual processing regions when viewing low spatial frequency houses, linked to the P100 component. Additionally, the BDD group exhibited hyperactivity in fusiform cortex when viewing high spatial frequency houses, linked to the N170 component. Greater activity in this component was associated with lower attractiveness ratings of faces. Results provide preliminary evidence of similar abnormal spatiotemporal activation in AN and BDD for configural/holistic information for appearance- and non-appearance-related stimuli. This suggests a common phenotype of abnormal early visual system functioning, which may contribute to perceptual distortions.

  2. Multifocal visual evoked potential and automated perimetry abnormalities in strabismic amblyopes.

    PubMed

    Greenstein, Vivienne C; Eggers, Howard M; Hood, Donald C

    2008-02-01

    To compare visual field abnormalities obtained with standard automated perimetry (SAP) to those obtained with the multifocal visual evoked potential (mfVEP) technique in strabismic amblyopes. Humphrey 24-2 visual fields (HVF) and mfVEPs were obtained from each eye of 12 strabismic amblyopes. For the mfVEP, amplitudes and latencies were analyzed and probability plots were derived. Multifocal VEP and HVF hemifields were abnormal if they had clusters of two or more contiguous points at p < 0.01, or three or more contiguous points at p < 0.05 with at least one at p < 0.01. An eye was abnormal if it had an abnormal hemifield. On SAP, amblyopic eyes had significantly higher foveal thresholds (p = 0.003) and lower mean deviation values (p = 0.005) than fellow eyes. For the mfVEP, 11 amblyopic and 6 fellow eyes were abnormal. Of the 11 amblyopic eyes, 6 were abnormal on SAP. The deficits extended from the center to mid periphery. Monocular mfVEP latencies were significantly decreased for amblyopic eyes compared with control eyes (p < 0.0002). Both techniques revealed deficits in visual function across the visual field in strabismic amblyopes, but the mfVEP revealed deficits in fellow eyes and in more amblyopic eyes. In addition, mfVEP response latencies for amblyopic eyes were shorter than normal.

  3. Is exposure to cocaine or cigarette smoke during pregnancy associated with infant visual abnormalities?

    PubMed

    Hajnal, Beatrice Latal; Ferriero, Donna M; Partridge, J Colin; Dempsey, Delia A; Good, William V

    2004-08-01

    The aim of this study was to assess the association between cocaine or cigarette smoke exposure in utero and visual outcome. A total of 153 healthy infants (89 males, 64 females; gestational age range 34 to 42 weeks) were prospectively enrolled in a masked, race-matched study. Quantitative analyses of urine and meconium were used to document exposure to cigarette smoke and cocaine. Infants with exposure to other illicit drugs, excepting marijuana, were excluded. At 6 weeks of age, grating acuity and visual system abnormalities (VSA; eyelid oedema, gaze abnormalities, and visual inattention) of 96 infants from the original study sample were assessed with the Teller acuity card procedure and a detailed neurological examination. Neither cocaine nor cigarette smoke exposure was associated with acuity or VSA. However, VSAs were associated with abnormal neurological examination, independent of drug exposure and other risk factors (odds ratio 7.9; 95% confidence interval 2.0 to 31.5;p=0.004). This unexpected finding could prove a helpful clinical marker for the infant at risk for neurological abnormalities.

  4. Visual Sensor Based Abnormal Event Detection with Moving Shadow Removal in Home Healthcare Applications

    PubMed Central

    Lee, Young-Sook; Chung, Wan-Young

    2012-01-01

    Vision-based abnormal event detection for home healthcare systems can be greatly improved using visual sensor-based techniques able to detect, track and recognize objects in the scene. However, in moving object detection and tracking processes, moving cast shadows can be misclassified as part of objects or moving objects. Shadow removal is an essential step for developing video surveillance systems. The goal of the primary is to design novel computer vision techniques that can extract objects more accurately and discriminate between abnormal and normal activities. To improve the accuracy of object detection and tracking, our proposed shadow removal algorithm is employed. Abnormal event detection based on visual sensor by using shape features variation and 3-D trajectory is presented to overcome the low fall detection rate. The experimental results showed that the success rate of detecting abnormal events was 97% with a false positive rate of 2%. Our proposed algorithm can allow distinguishing diverse fall activities such as forward falls, backward falls, and falling asides from normal activities. PMID:22368486

  5. Abnormalities in the Visual Processing of Viewing Complex Visual Stimuli Amongst Individuals With Body Image Concern.

    PubMed

    Duncum, A J F; Atkins, K J; Beilharz, F L; Mundy, M E

    2016-01-01

    Individuals with body dysmorphic disorder (BDD) and clinically concerning body-image concern (BIC) appear to possess abnormalities in the way they perceive visual information in the form of a bias towards local visual processing. As inversion interrupts normal global processing, forcing individuals to process locally, an upright-inverted stimulus discrimination task was used to investigate this phenomenon. We examined whether individuals with nonclinical, yet high levels of BIC would show signs of this bias, in the form of reduced inversion effects (i.e., increased local processing). Furthermore, we assessed whether this bias appeared for general visual stimuli or specifically for appearance-related stimuli, such as faces and bodies. Participants with high-BIC (n = 25) and low-BIC (n = 30) performed a stimulus discrimination task with upright and inverted faces, scenes, objects, and bodies. Unexpectedly, the high-BIC group showed an increased inversion effect compared to the low-BIC group, indicating perceptual abnormalities may not be present as local processing biases, as originally thought. There was no significant difference in performance across stimulus types, signifying that any visual processing abnormalities may be general rather than appearance-based. This has important implications for whether visual processing abnormalities are predisposing factors for BDD or develop throughout the disorder.

  6. Abnormal visual scan paths: a psychophysiological marker of delusions in schizophrenia.

    PubMed

    Phillips, M L; David, A S

    1998-02-09

    The role of the visual scan path as a psychophysiological marker of visual attention has been highlighted previously (Phillips and David, 1994). We investigated information processing in schizophrenic patients with severe delusions and again when the delusions were subsiding using visual scan path measurements. We aimed to demonstrate a specific deficit in processing human faces in deluded subjects by relating this to abnormal viewing strategies. Scan paths were measured in six deluded and five non-deluded schizophrenics (matched for medication and negative symptoms), and nine age-matched normal controls. Deluded subjects had abnormal scan paths in a recognition task, fixating non-feature areas significantly more than controls, but were equally accurate. Re-testing after improvement in delusional conviction revealed fewer group differences. The results suggest state-dependent abnormal information processing in schizophrenics when deluded, with reliance on less-salient visual information for decision-making.

  7. Visual scan paths are abnormal in deluded schizophrenics.

    PubMed

    Phillips, M L; David, A S

    1997-01-01

    One explanation for delusion formation is that they result from distorted appreciation of complex stimuli. The study investigated delusions in schizophrenia using a physiological marker of visual attention and information processing, the visual scan path-a map tracing the direction and duration of gaze when an individual views a stimulus. The aim was to demonstrate the presence of a specific deficit in processing meaningful stimuli (e.g. human faces) in deluded schizophrenics (DS) by relating this to abnormal viewing strategies. Visual scan paths were measured in acutely-deluded (n = 7) and non-deluded (n = 7) schizophrenics matched for medication, illness duration and negative symptoms, plus 10 age-matched normal controls. DS employed abnormal strategies for viewing single faces and face pairs in a recognition task, staring at fewer points and fixating non-feature areas to a significantly greater extent than both control groups (P < 0.05). The results indicate that DS direct their attention to less salient visual information when viewing faces. Future paradigms employing more complex stimuli and testing DS when less-deluded will allow further clarification of the relationship between viewing strategies and delusions.

  8. Sparse coding can predict primary visual cortex receptive field changes induced by abnormal visual input.

    PubMed

    Hunt, Jonathan J; Dayan, Peter; Goodhill, Geoffrey J

    2013-01-01

    Receptive fields acquired through unsupervised learning of sparse representations of natural scenes have similar properties to primary visual cortex (V1) simple cell receptive fields. However, what drives in vivo development of receptive fields remains controversial. The strongest evidence for the importance of sensory experience in visual development comes from receptive field changes in animals reared with abnormal visual input. However, most sparse coding accounts have considered only normal visual input and the development of monocular receptive fields. Here, we applied three sparse coding models to binocular receptive field development across six abnormal rearing conditions. In every condition, the changes in receptive field properties previously observed experimentally were matched to a similar and highly faithful degree by all the models, suggesting that early sensory development can indeed be understood in terms of an impetus towards sparsity. As previously predicted in the literature, we found that asymmetries in inter-ocular correlation across orientations lead to orientation-specific binocular receptive fields. Finally we used our models to design a novel stimulus that, if present during rearing, is predicted by the sparsity principle to lead robustly to radically abnormal receptive fields.

  9. Sparse Coding Can Predict Primary Visual Cortex Receptive Field Changes Induced by Abnormal Visual Input

    PubMed Central

    Hunt, Jonathan J.; Dayan, Peter; Goodhill, Geoffrey J.

    2013-01-01

    Receptive fields acquired through unsupervised learning of sparse representations of natural scenes have similar properties to primary visual cortex (V1) simple cell receptive fields. However, what drives in vivo development of receptive fields remains controversial. The strongest evidence for the importance of sensory experience in visual development comes from receptive field changes in animals reared with abnormal visual input. However, most sparse coding accounts have considered only normal visual input and the development of monocular receptive fields. Here, we applied three sparse coding models to binocular receptive field development across six abnormal rearing conditions. In every condition, the changes in receptive field properties previously observed experimentally were matched to a similar and highly faithful degree by all the models, suggesting that early sensory development can indeed be understood in terms of an impetus towards sparsity. As previously predicted in the literature, we found that asymmetries in inter-ocular correlation across orientations lead to orientation-specific binocular receptive fields. Finally we used our models to design a novel stimulus that, if present during rearing, is predicted by the sparsity principle to lead robustly to radically abnormal receptive fields. PMID:23675290

  10. Abnormalities of Object Visual Processing in Body Dysmorphic Disorder

    PubMed Central

    Feusner, Jamie D.; Hembacher, Emily; Moller, Hayley; Moody, Teena D.

    2013-01-01

    Background Individuals with body dysmorphic disorder may have perceptual distortions for their appearance. Previous studies suggest imbalances in detailed relative to configural/holistic visual processing when viewing faces. No study has investigated the neural correlates of processing non-symptom-related stimuli. The objective of this study was to determine whether individuals with body dysmorphic disorder have abnormal patterns of brain activation when viewing non-face/non-body object stimuli. Methods Fourteen medication-free participants with DSM-IV body dysmorphic disorder and 14 healthy controls participated. We performed functional magnetic resonance imaging while participants matched photographs of houses that were unaltered, contained only high spatial frequency (high detail) information, or only low spatial frequency (low detail) information. The primary outcome was group differences in blood oxygen level-dependent signal changes. Results The body dysmorphic disorder group showed lesser activity in the parahippocampal gyrus, lingual gyrus, and precuneus for low spatial frequency images. There were greater activations in medial prefrontal regions for high spatial frequency images, although no significant differences when compared to a low-level baseline. Greater symptom severity was associated with lesser activity in dorsal occipital cortex and ventrolateral prefrontal cortex for normal and high spatial frequency images. Conclusions Individuals with body dysmorphic disorder have abnormal brain activation patterns when viewing objects. Hypoactivity in visual association areas for configural and holistic (low detail) elements and abnormal allocation of prefrontal systems for details is consistent with a model of imbalances in global vs. local processing. This may occur not only for appearance but also for general stimuli unrelated to their symptoms. PMID:21557897

  11. Childhood visual impairment: normal and abnormal visual function in the context of developmental disability.

    PubMed

    Nyong'o, Omondi L; Del Monte, Monte A

    2008-12-01

    Abnormal or failed development of vision in children may give rise to varying degrees of visual impairment and disability. Disease and organ-specific mechanisms by which visual impairments arise are presented. The presentation of these mechanisms, along with an explanation of established pathologic processes and correlative up-to-date clinical and social research in the field of pediatrics, ophthalmology, and rehabilitation medicine are discussed. The goal of this article is to enhance the practitioner's recognition and care for children with developmental disability associated with visual impairment.

  12. Isolated cortical visual loss with subtle brain MRI abnormalities in a case of hypoxic-ischemic encephalopathy.

    PubMed

    Margolin, Edward; Gujar, Sachin K; Trobe, Jonathan D

    2007-12-01

    A 16-year-old boy who was briefly asystolic and hypotensive after a motor vehicle accident complained of abnormal vision after recovering consciousness. Visual acuity was normal, but visual fields were severely constricted without clear hemianopic features. The ophthalmic examination was otherwise normal. Brain MRI performed 11 days after the accident showed no pertinent abnormalities. At 6 months after the event, brain MRI demonstrated brain volume loss in the primary visual cortex and no other abnormalities. One year later, visual fields remained severely constricted; neurologic examination, including formal neuropsychometric testing, was normal. This case emphasizes the fact that hypoxic-ischemic encephalopathy (HIE) may cause enduring damage limited to primary visual cortex and that the MRI abnormalities may be subtle. These phenomena should be recognized in the management of patients with HIE.

  13. Transdiagnostic psychiatric symptoms related to visual evoked potential abnormalities.

    PubMed

    Bedwell, Jeffrey S; Butler, Pamela D; Chan, Chi C; Trachik, Benjamin J

    2015-12-15

    Visual processing abnormalities have been reported across a range of psychotic and mood disorders, but are typically examined within a particular disorder. The current study used a novel transdiagnostic approach to examine diagnostic classes, clinician-rated current symptoms, and self-reported personality traits in relation to visual processing abnormalities. We examined transient visual-evoked potentials (VEPs) from 48 adults (56% female), representing a wide range of psychotic and mood disorders, as well as individuals with no history of psychiatric disorder. Stimuli were low contrast check arrays presented on green and red backgrounds. Pairwise comparisons between individuals with schizophrenia-spectrum disorders (SSD), chronic mood disorders (CMD), and nonpsychiatric controls (NC) revealed no overall differences for either P1 or N1 amplitude. However, there was a significant interaction with the color background in which the NC group showed a significant increase in P1 amplitude to the red, vs. green, background, while the SSD group showed no change. This was related to an increase in social anhedonia and general negative symptoms. Stepwise regressions across the entire sample revealed that individuals with greater apathy and/or eccentric behavior had a reduced P1 amplitude. These relationships provide clues for uncovering the underlying causal pathology for these transdiagnostic symptoms. Copyright © 2015 Elsevier Ireland Ltd. All rights reserved.

  14. Basic abnormalities in visual processing affect face processing at an early age in autism spectrum disorder.

    PubMed

    Vlamings, Petra Hendrika Johanna Maria; Jonkman, Lisa Marthe; van Daalen, Emma; van der Gaag, Rutger Jan; Kemner, Chantal

    2010-12-15

    A detailed visual processing style has been noted in autism spectrum disorder (ASD); this contributes to problems in face processing and has been directly related to abnormal processing of spatial frequencies (SFs). Little is known about the early development of face processing in ASD and the relation with abnormal SF processing. We investigated whether young ASD children show abnormalities in low spatial frequency (LSF, global) and high spatial frequency (HSF, detailed) processing and explored whether these are crucially involved in the early development of face processing. Three- to 4-year-old children with ASD (n = 22) were compared with developmentally delayed children without ASD (n = 17). Spatial frequency processing was studied by recording visual evoked potentials from visual brain areas while children passively viewed gratings (HSF/LSF). In addition, children watched face stimuli with different expressions, filtered to include only HSF or LSF. Enhanced activity in visual brain areas was found in response to HSF versus LSF information in children with ASD, in contrast to control subjects. Furthermore, facial-expression processing was also primarily driven by detail in ASD. Enhanced visual processing of detailed (HSF) information is present early in ASD and occurs for neutral (gratings), as well as for socially relevant stimuli (facial expressions). These data indicate that there is a general abnormality in visual SF processing in early ASD and are in agreement with suggestions that a fast LSF subcortical face processing route might be affected in ASD. This could suggest that abnormal visual processing is causative in the development of social problems in ASD. Copyright © 2010 Society of Biological Psychiatry. Published by Elsevier Inc. All rights reserved.

  15. Brain Growth Rate Abnormalities Visualized in Adolescents with Autism

    PubMed Central

    Hua, Xue; Thompson, Paul M.; Leow, Alex D.; Madsen, Sarah K.; Caplan, Rochelle; Alger, Jeffry R.; O’Neill, Joseph; Joshi, Kishori; Smalley, Susan L.; Toga, Arthur W.; Levitt, Jennifer G.

    2014-01-01

    Autism spectrum disorder (ASD) is a heterogeneous disorder of brain development with wide-ranging cognitive deficits. Typically diagnosed before age 3, ASD is behaviorally defined but patients are thought to have protracted alterations in brain maturation. With longitudinal magnetic resonance imaging (MRI), we mapped an anomalous developmental trajectory of the brains of autistic compared to those of typically developing children and adolescents. Using tensor-based morphometry (TBM), we created 3D maps visualizing regional tissue growth rates based on longitudinal brain MRI scans of 13 autistic and 7 typically developing boys (mean age/inter-scan interval: autism 12.0 ± 2.3 years/2.9 ± 0.9 years; control 12.3 ± 2.4/2.8 ± 0.8). The typically developing boys demonstrated strong whole-brain white matter growth during this period, but the autistic boys showed abnormally slowed white matter development (p = 0.03, corrected), especially in the parietal (p = 0.008), temporal (p = 0.03) and occipital lobes (p =0.02). We also visualized abnormal overgrowth in autism in some gray matter structures, such as the putamen and anterior cingulate cortex. Our findings reveal aberrant growth rates in brain regions implicated in social impairment, communication deficits and repetitive behaviors in autism, suggesting that growth rate abnormalities persist into adolescence. TBM revealed persisting growth rate anomalies long after diagnosis, which has implications for evaluation of therapeutic effects. PMID:22021093

  16. Brain growth rate abnormalities visualized in adolescents with autism.

    PubMed

    Hua, Xue; Thompson, Paul M; Leow, Alex D; Madsen, Sarah K; Caplan, Rochelle; Alger, Jeffry R; O'Neill, Joseph; Joshi, Kishori; Smalley, Susan L; Toga, Arthur W; Levitt, Jennifer G

    2013-02-01

    Autism spectrum disorder is a heterogeneous disorder of brain development with wide ranging cognitive deficits. Typically diagnosed before age 3, autism spectrum disorder is behaviorally defined but patients are thought to have protracted alterations in brain maturation. With longitudinal magnetic resonance imaging (MRI), we mapped an anomalous developmental trajectory of the brains of autistic compared with those of typically developing children and adolescents. Using tensor-based morphometry, we created 3D maps visualizing regional tissue growth rates based on longitudinal brain MRI scans of 13 autistic and seven typically developing boys (mean age/interscan interval: autism 12.0 ± 2.3 years/2.9 ± 0.9 years; control 12.3 ± 2.4/2.8 ± 0.8). The typically developing boys demonstrated strong whole brain white matter growth during this period, but the autistic boys showed abnormally slowed white matter development (P = 0.03, corrected), especially in the parietal (P = 0.008), temporal (P = 0.03), and occipital lobes (P = 0.02). We also visualized abnormal overgrowth in autism in gray matter structures such as the putamen and anterior cingulate cortex. Our findings reveal aberrant growth rates in brain regions implicated in social impairment, communication deficits and repetitive behaviors in autism, suggesting that growth rate abnormalities persist into adolescence. Tensor-based morphometry revealed persisting growth rate anomalies long after diagnosis, which has implications for evaluation of therapeutic effects. Copyright © 2011 Wiley Periodicals, Inc.

  17. Effect of Developmental Binocular Vision Abnormalities on Visual Vertigo Symptoms and Treatment Outcome.

    PubMed

    Pavlou, Marousa; Acheson, James; Nicolaou, Despina; Fraser, Clare L; Bronstein, Adolfo M; Davies, Rosalyn A

    2015-10-01

    Customized vestibular rehabilitation incorporating optokinetic (OK) stimulation improves visual vertigo (VV) symptoms; however, the degree of improvement varies among individuals. Binocular vision abnormalities (misalignment of ocular axis, ie, strabismus) may be a potential risk factor. This study aimed to investigate the influence of binocular vision abnormalities on VV symptoms and treatment outcome. Sixty subjects with refractory peripheral vestibular symptoms underwent an orthoptic assessment after being recruited for participation in an 8-week customized program incorporating OK training via a full-field visual environment rotator or video display, supervised or unsupervised. Treatment response was assessed at baseline and at 8 weeks with dynamic posturography, Functional Gait Assessment (FGA), and questionnaires for symptoms, symptom triggers, and psychological state. As no significant effect of OK training type was noted for any variables, data were combined and new groups identified on the basis of the absence or presence of a binocular vision abnormality. A total of 34 among 60 subjects consented to the orthoptic assessment, of whom 8 of the 34 had binocular vision abnormalities and 30 of the 34 subjects completed both the binocular function assessment and vestibular rehabilitation program. No significant between-group differences were noted at baseline. The only significant between-group difference was observed for pre-/post-VV symptom change (P = 0.01), with significant improvements noted only for the group without binocular vision abnormalities (P < 0.0005). Common vestibular symptoms, posturography, and the FGA improved significantly for both groups (P < 0.05). Binocular vision abnormalities may affect VV symptom improvement. These findings may have important implications for the management of subjects with refractory vestibular symptoms.Video Abstract available for insights from the authors regarding clinical implication of the study findings (see

  18. Visual Field Abnormalities among Adolescent Boys with Hearing Impairments

    PubMed Central

    KHORRAMI-NEJAD, Masoud; HERAVIAN, Javad; SEDAGHAT, Mohamad-Reza; MOMENI-MOGHADAM, Hamed; SOBHANI-RAD, Davood; ASKARIZADEH, Farshad

    2016-01-01

    The aim of this study was to compare the visual field (VF) categorizations (based on the severity of VF defects) between adolescent boys with hearing impairments and those with normal hearing. This cross-sectional study involved the evaluation of the VF of 64 adolescent boys with hearing impairments and 68 age-matched boys with normal hearing at high schools in Tehran, Iran, in 2013. All subjects had an intelligence quotient (IQ) > 70. The hearing impairments were classified based on severity and time of onset. Participants underwent a complete eye examination, and the VFs were investigated using automated perimetry with a Humphrey Visual Field Analyzer. This device was used to determine their foveal threshold (FT), mean deviation (MD), and Glaucoma Hemifield Test (GHT) results. Most (50%) of the boys with hearing impairments had profound hearing impairments. There was no significant between-group difference in age (P = 0.49) or IQ (P = 0.13). There was no between-group difference in the corrected distance visual acuity (P = 0.183). According to the FT, MD, and GHT results, the percentage of boys with abnormal VFs in the hearing impairment group was significantly greater than that in the normal hearing group: 40.6% vs. 22.1%, 59.4% vs. 19.1%, and 31.2% vs. 8.8%, respectively (P < 0.0001). The mean MD in the hearing impairment group was significantly worse than that in the normal hearing group (-0.79 ± 2.04 and -4.61 ± 6.52 dB, respectively, P < 0.0001), and the mean FT was also significantly worse (38.97 ± 1.66 vs. 35.30 ± 1.43 dB, respectively, P <0.0001). Moreover, there was a significant between-group difference in the GHT results (P < 0.0001). Thus, there were higher percentages of boys with VF abnormalities and higher mean MD, FT, and GHT results among those with hearing impairments compared to those with normal hearing. These findings emphasize the need for detailed VF assessments for patients with hearing impairments. PMID:28293650

  19. Abnormal late visual responses and alpha oscillations in neurofibromatosis type 1: a link to visual and attention deficits

    PubMed Central

    2014-01-01

    Background Neurofibromatosis type 1 (NF1) affects several areas of cognitive function including visual processing and attention. We investigated the neural mechanisms underlying the visual deficits of children and adolescents with NF1 by studying visual evoked potentials (VEPs) and brain oscillations during visual stimulation and rest periods. Methods Electroencephalogram/event-related potential (EEG/ERP) responses were measured during visual processing (NF1 n = 17; controls n = 19) and idle periods with eyes closed and eyes open (NF1 n = 12; controls n = 14). Visual stimulation was chosen to bias activation of the three detection mechanisms: achromatic, red-green and blue-yellow. Results We found significant differences between the groups for late chromatic VEPs and a specific enhancement in the amplitude of the parieto-occipital alpha amplitude both during visual stimulation and idle periods. Alpha modulation and the negative influence of alpha oscillations in visual performance were found in both groups. Conclusions Our findings suggest abnormal later stages of visual processing and enhanced amplitude of alpha oscillations supporting the existence of deficits in basic sensory processing in NF1. Given the link between alpha oscillations, visual perception and attention, these results indicate a neural mechanism that might underlie the visual sensitivity deficits and increased lapses of attention observed in individuals with NF1. PMID:24559228

  20. Low-Intensity Repetitive Transcranial Magnetic Stimulation Improves Abnormal Visual Cortical Circuit Topography and Upregulates BDNF in Mice

    PubMed Central

    Makowiecki, Kalina; Harvey, Alan R.; Sherrard, Rachel M.

    2014-01-01

    Repetitive transcranial magnetic stimulation (rTMS) is increasingly used as a treatment for neurological and psychiatric disorders. Although the induced field is focused on a target region during rTMS, adjacent areas also receive stimulation at a lower intensity and the contribution of this perifocal stimulation to network-wide effects is poorly defined. Here, we examined low-intensity rTMS (LI-rTMS)-induced changes on a model neural network using the visual systems of normal (C57Bl/6J wild-type, n = 22) and ephrin-A2A5−/− (n = 22) mice, the latter possessing visuotopic anomalies. Mice were treated with LI-rTMS or sham (handling control) daily for 14 d, then fluorojade and fluororuby were injected into visual cortex. The distribution of dorsal LGN (dLGN) neurons and corticotectal terminal zones (TZs) was mapped and disorder defined by comparing their actual location with that predicted by injection sites. In the afferent geniculocortical projection, LI-rTMS decreased the abnormally high dispersion of retrogradely labeled neurons in the dLGN of ephrin-A2A5−/− mice, indicating geniculocortical map refinement. In the corticotectal efferents, LI-rTMS improved topography of the most abnormal TZs in ephrin-A2A5−/− mice without altering topographically normal TZs. To investigate a possible molecular mechanism for LI-rTMS-induced structural plasticity, we measured brain derived neurotrophic factor (BDNF) in the visual cortex and superior colliculus after single and multiple stimulations. BDNF was upregulated after a single stimulation for all groups, but only sustained in the superior colliculus of ephrin-A2A5−/− mice. Our results show that LI-rTMS upregulates BDNF, promoting a plastic environment conducive to beneficial reorganization of abnormal cortical circuits, information that has important implications for clinical rTMS. PMID:25100609

  1. Analysis and visualization of chromosomal abnormalities in SNP data with SNPscan

    PubMed Central

    Ting, Jason C; Ye, Ying; Thomas, George H; Ruczinski, Ingo; Pevsner, Jonathan

    2006-01-01

    Background A variety of diseases are caused by chromosomal abnormalities such as aneuploidies (having an abnormal number of chromosomes), microdeletions, microduplications, and uniparental disomy. High density single nucleotide polymorphism (SNP) microarrays provide information on chromosomal copy number changes, as well as genotype (heterozygosity and homozygosity). SNP array studies generate multiple types of data for each SNP site, some with more than 100,000 SNPs represented on each array. The identification of different classes of anomalies within SNP data has been challenging. Results We have developed SNPscan, a web-accessible tool to analyze and visualize high density SNP data. It enables researchers (1) to visually and quantitatively assess the quality of user-generated SNP data relative to a benchmark data set derived from a control population, (2) to display SNP intensity and allelic call data in order to detect chromosomal copy number anomalies (duplications and deletions), (3) to display uniparental isodisomy based on loss of heterozygosity (LOH) across genomic regions, (4) to compare paired samples (e.g. tumor and normal), and (5) to generate a file type for viewing SNP data in the University of California, Santa Cruz (UCSC) Human Genome Browser. SNPscan accepts data exported from Affymetrix Copy Number Analysis Tool as its input. We validated SNPscan using data generated from patients with known deletions, duplications, and uniparental disomy. We also inspected previously generated SNP data from 90 apparently normal individuals from the Centre d'Étude du Polymorphisme Humain (CEPH) collection, and identified three cases of uniparental isodisomy, four females having an apparently mosaic X chromosome, two mislabelled SNP data sets, and one microdeletion on chromosome 2 with mosaicism from an apparently normal female. These previously unrecognized abnormalities were all detected using SNPscan. The microdeletion was independently confirmed by

  2. Preserved local but disrupted contextual figure-ground influences in an individual with abnormal function of intermediate visual areas

    PubMed Central

    Brooks, Joseph L.; Gilaie-Dotan, Sharon; Rees, Geraint; Bentin, Shlomo; Driver, Jon

    2012-01-01

    Visual perception depends not only on local stimulus features but also on their relationship to the surrounding stimulus context, as evident in both local and contextual influences on figure-ground segmentation. Intermediate visual areas may play a role in such contextual influences, as we tested here by examining LG, a rare case of developmental visual agnosia. LG has no evident abnormality of brain structure and functional neuroimaging showed relatively normal V1 function, but his intermediate visual areas (V2/V3) function abnormally. We found that contextual influences on figure-ground organization were selectively disrupted in LG, while local sources of figure-ground influences were preserved. Effects of object knowledge and familiarity on figure-ground organization were also significantly diminished. Our results suggest that the mechanisms mediating contextual and familiarity influences on figure-ground organization are dissociable from those mediating local influences on figure-ground assignment. The disruption of contextual processing in intermediate visual areas may play a role in the substantial object recognition difficulties experienced by LG. PMID:22947116

  3. Abnormal early brain responses during visual search are evident in schizophrenia but not bipolar affective disorder.

    PubMed

    VanMeerten, Nicolaas J; Dubke, Rachel E; Stanwyck, John J; Kang, Seung Suk; Sponheim, Scott R

    2016-01-01

    People with schizophrenia show deficits in processing visual stimuli but neural abnormalities underlying the deficits are unclear and it is unknown whether such functional brain abnormalities are present in other severe mental disorders or in individuals who carry genetic liability for schizophrenia. To better characterize brain responses underlying visual search deficits and test their specificity to schizophrenia we gathered behavioral and electrophysiological responses during visual search (i.e., Span of Apprehension [SOA] task) from 38 people with schizophrenia, 31 people with bipolar disorder, 58 biological relatives of people with schizophrenia, 37 biological relatives of people with bipolar disorder, and 65 non-psychiatric control participants. Through subtracting neural responses associated with purely sensory aspects of the stimuli we found that people with schizophrenia exhibited reduced early posterior task-related neural responses (i.e., Span Endogenous Negativity [SEN]) while other groups showed normative responses. People with schizophrenia exhibited longer reaction times than controls during visual search but nearly identical accuracy. Those individuals with schizophrenia who had larger SENs performed more efficiently (i.e., shorter reaction times) on the SOA task suggesting that modulation of early visual cortical responses facilitated their visual search. People with schizophrenia also exhibited a diminished P300 response compared to other groups. Unaffected first-degree relatives of people with bipolar disorder and schizophrenia showed an amplified N1 response over posterior brain regions in comparison to other groups. Diminished early posterior brain responses are associated with impaired visual search in schizophrenia and appear to be specifically associated with the neuropathology of schizophrenia. Published by Elsevier B.V.

  4. Abnormal/Emergency Situations. Impact of Unmanned Aircraft Systems Emergency and Abnormal Events on the National Airspace System

    NASA Technical Reports Server (NTRS)

    2006-01-01

    Access 5 analyzed the differences between UAS and manned aircraft operations under five categories of abnormal or emergency situations: Link Failure, Lost Communications, Onboard System Failures, Control Station Failures and Abnormal Weather. These analyses were made from the vantage point of the impact that these operations have on the US air traffic control system, with recommendations for new policies and procedures included where appropriate.

  5. Neuron analysis of visual perception

    NASA Technical Reports Server (NTRS)

    Chow, K. L.

    1980-01-01

    The receptive fields of single cells in the visual system of cat and squirrel monkey were studied investigating the vestibular input affecting the cells, and the cell's responses during visual discrimination learning process. The receptive field characteristics of the rabbit visual system, its normal development, its abnormal development following visual deprivation, and on the structural and functional re-organization of the visual system following neo-natal and prenatal surgery were also studied. The results of each individual part of each investigation are detailed.

  6. Looking you in the mouth: abnormal gaze in autism resulting from impaired top-down modulation of visual attention.

    PubMed

    Neumann, Dirk; Spezio, Michael L; Piven, Joseph; Adolphs, Ralph

    2006-12-01

    People with autism are impaired in their social behavior, including their eye contact with others, but the processes that underlie this impairment remain elusive. We combined high-resolution eye tracking with computational modeling in a group of 10 high-functioning individuals with autism to address this issue. The group fixated the location of the mouth in facial expressions more than did matched controls, even when the mouth was not shown, even in faces that were inverted and most noticeably at latencies of 200-400 ms. Comparisons with a computational model of visual saliency argue that the abnormal bias for fixating the mouth in autism is not driven by an exaggerated sensitivity to the bottom-up saliency of the features, but rather by an abnormal top-down strategy for allocating visual attention.

  7. A comparison of visual and quantitative methods to identify interstitial lung abnormalities.

    PubMed

    Kliment, Corrine R; Araki, Tetsuro; Doyle, Tracy J; Gao, Wei; Dupuis, Josée; Latourelle, Jeanne C; Zazueta, Oscar E; Fernandez, Isis E; Nishino, Mizuki; Okajima, Yuka; Ross, James C; Estépar, Raúl San José; Diaz, Alejandro A; Lederer, David J; Schwartz, David A; Silverman, Edwin K; Rosas, Ivan O; Washko, George R; O'Connor, George T; Hatabu, Hiroto; Hunninghake, Gary M

    2015-10-29

    Evidence suggests that individuals with interstitial lung abnormalities (ILA) on a chest computed tomogram (CT) may have an increased risk to develop a clinically significant interstitial lung disease (ILD). Although methods used to identify individuals with ILA on chest CT have included both automated quantitative and qualitative visual inspection methods, there has been not direct comparison between these two methods. To investigate this relationship, we created lung density metrics and compared these to visual assessments of ILA. To provide a comparison between ILA detection methods based on visual assessment we generated measures of high attenuation areas (HAAs, defined by attenuation values between -600 and -250 Hounsfield Units) in >4500 participants from both the COPDGene and Framingham Heart studies (FHS). Linear and logistic regressions were used for analyses. Increased measures of HAAs (in ≥ 10 % of the lung) were significantly associated with ILA defined by visual inspection in both cohorts (P < 0.0001); however, the positive predictive values were not very high (19 % in COPDGene and 13 % in the FHS). In COPDGene, the association between HAAs and ILA defined by visual assessment were modified by the percentage of emphysema and body mass index. Although increased HAAs were associated with reductions in total lung capacity in both cohorts, there was no evidence for an association between measurement of HAAs and MUC5B promoter genotype in the FHS. Our findings demonstrate that increased measures of lung density may be helpful in determining the severity of lung volume reduction, but alone, are not strongly predictive of ILA defined by visual assessment. Moreover, HAAs were not associated with MUC5B promoter genotype.

  8. Enhanced visualization of abnormalities in digital-mammographic images

    NASA Astrophysics Data System (ADS)

    Young, Susan S.; Moore, William E.

    2002-05-01

    This paper describes two new presentation methods that are intended to improve the ability of radiologists to visualize abnormalities in mammograms by enhancing the appearance of the breast parenchyma pattern relative to the fatty-tissue surroundings. The first method, referred to as mountain- view, is obtained via multiscale edge decomposition through filter banks. The image is displayed in a multiscale edge domain that causes the image to have a topographic-like appearance. The second method displays the image in the intensity domain and is referred to as contrast-enhancement presentation. The input image is first passed through a decomposition filter bank to produce a filtered output (Id). The image at the lowest resolution is processed using a LUT (look-up table) to produce a tone scaled image (I'). The LUT is designed to optimally map the code value range corresponding to the parenchyma pattern in the mammographic image into the dynamic range of the output medium. The algorithm uses a contrast weight control mechanism to produce the desired weight factors to enhance the edge information corresponding to the parenchyma pattern. The output image is formed using a reconstruction filter bank through I' and enhanced Id.

  9. Vitreoretinal interface abnormalities in middle-aged adults with visual impairment in the UK Biobank study: prevalence, impact on visual acuity and associations.

    PubMed

    McKibbin, Martin; Farragher, Tracey; Shickle, Darren

    2017-01-01

    The aim of this study was to determine the prevalence of vitreoretinal interface abnormalities (VRIA), the degree of visual impairment and associations with VRIA among adults, aged 40-69 years, in the UK Biobank study. Colour fundus photographs and spectral domain optical coherence tomography images were graded for 25% of the 8359 UK Biobank participants with mild visual impairment or worse (LogMAR >0.3 or Snellen <6/12) in at least one eye. The prevalence and contribution of VRIA to visual impairment was determined and multinomial logistic regression models were used to investigate association with known risk factors and other predetermined socioeconomic, biometric, lifestyle and medical variables for cases and matched controls. The minimum prevalence of any VRIA was 17.6% and 8.1% in the eyes with and without visual impairment, respectively. VRIA were identified as the primary cause of visual impairment in 3.6% of eyes. Although epiretinal membrane and vitreomacular traction were the most common VRIA, the degree of visual impairment was typically milder with these than with other VRIA. Visual impairment with a VRIA was positively associated with increasing age (relative risk ratio (RRR) 1.22 (95% CI 1.07 to 1.40)), female gender (RRR 1.28; 1.08 to 1.52) and Asian or Asian British ethnicity (RRR 1.60; 1.10 to 2.32). VRIA are common in middle-aged adults in the UK Biobank study, especially in eyes with visual impairment. VRIA were considered to be the primary cause of visual impairment in 3.6% of all eyes with visual impairment, although there was variation in the degree of visual impairment for each type of VRIA.

  10. Vitreoretinal interface abnormalities in middle-aged adults with visual impairment in the UK Biobank study: prevalence, impact on visual acuity and associations

    PubMed Central

    Farragher, Tracey; Shickle, Darren

    2017-01-01

    Objective The aim of this study was to determine the prevalence of vitreoretinal interface abnormalities (VRIA), the degree of visual impairment and associations with VRIA among adults, aged 40–69 years, in the UK Biobank study. Methods and analysis Colour fundus photographs and spectral domain optical coherence tomography images were graded for 25% of the 8359 UK Biobank participants with mild visual impairment or worse (LogMAR >0.3 or Snellen <6/12) in at least one eye. The prevalence and contribution of VRIA to visual impairment was determined and multinomial logistic regression models were used to investigate association with known risk factors and other predetermined socioeconomic, biometric, lifestyle and medical variables for cases and matched controls. Results The minimum prevalence of any VRIA was 17.6% and 8.1% in the eyes with and without visual impairment, respectively. VRIA were identified as the primary cause of visual impairment in 3.6% of eyes. Although epiretinal membrane and vitreomacular traction were the most common VRIA, the degree of visual impairment was typically milder with these than with other VRIA. Visual impairment with a VRIA was positively associated with increasing age (relative risk ratio (RRR) 1.22 (95% CI 1.07 to 1.40)), female gender (RRR 1.28; 1.08 to 1.52) and Asian or Asian British ethnicity (RRR 1.60; 1.10 to 2.32). Conclusions VRIA are common in middle-aged adults in the UK Biobank study, especially in eyes with visual impairment. VRIA were considered to be the primary cause of visual impairment in 3.6% of all eyes with visual impairment, although there was variation in the degree of visual impairment for each type of VRIA. PMID:29354705

  11. Retinal abnormalities in β-thalassemia major

    PubMed Central

    Bhoiwala, Devang L.; Dunaief, Joshua L.

    2015-01-01

    Patients with beta (β)-thalassemia (β-TM: thalassemia major, β-TI: thalassemia intermedia) have a variety of complications that may affect all organs, including the eye. Ocular abnormalities include retinal pigment epithelium degeneration, angioid streaks, venous tortuosity, night blindness, visual field defects, decreased visual acuity, color vision abnormalities, and acute visual loss. Patients with β-TM are transfusion dependent and require iron chelation therapy (ICT) in order to survive. Retinal degeneration may result from either retinal iron accumulation from transfusion-induced iron overload or retinal toxicity induced by ICT. Some who were never treated with ICT exhibited retinopathy, and others receiving ICT had chelator-induced retinopathy. We will focus on retinal abnormalities present in individuals with β-TM viewed in light of new findings on the mechanisms and manifestations of retinal iron toxicity. PMID:26325202

  12. Visual Alert System

    NASA Technical Reports Server (NTRS)

    1985-01-01

    A visual alert system resulted from circuitry developed by Applied Cybernetics Systems for Langley as part of a space related telemetry system. James Campman, Applied Cybernetics president, left the company and founded Grace Industries, Inc. to manufacture security devices based on the Langley technology. His visual alert system combines visual and audible alerts for hearing impaired people. The company also manufactures an arson detection device called the electronic nose, and is currently researching additional applications of the NASA technology.

  13. Visual-Spatial Orienting in Autism.

    ERIC Educational Resources Information Center

    Wainwright, J. Ann; Bryson, Susan E.

    1996-01-01

    Visual-spatial orienting in 10 high-functioning adults with autism was examined. Compared to controls, subjects responded faster to central than to lateral stimuli, and showed a left visual field advantage for stimulus detection only when laterally presented. Abnormalities in attention shifting and coordination of attentional and motor systems are…

  14. Reflex epilepsy and reflex seizures of the visual system: a clinical review.

    PubMed

    Zifkin, B G; Kasteleijn-Nolst Trenité, D

    2000-09-01

    Reflex epilepsy of the visual system is charecterised by seizures precipitated by visual stimuli. EEG responses to intermittent photic stimulation depend on the age and sex of the subject and on how stimulation is performed: abnormalities are commonest in children and adolescents, especially girls. Only generalised paroxysmal epileptiform discharges are clearly linked to epilepsy. Abnormal responses may occur in asymptomatic subjects, especially children. Photosensitivity has an important genetic component. Some patients are sensitive to patterns, suggesting an occipital trigger for these events. Myoclonus and generalised convulsive and nonconvulsive seizures may be triggered by visual stimuli. Partial seizures occur less often and can be confused with migraine. Although usually idiopathic, photosensitive epilepsy may occur in degenerative diseases and some patients with photosensitive partial seizures have brain lesions. Sunlight and video screens, including television, video games, and computer displays, are the commonest environmental triggers of photosensitive seizures. Outbreaks of triggered seizures have occurred when certain flashing or patterned images have been broadcast. There are regulations to prevent this in some countries only. Pure photosensitive epilepsy has a good prognosis. There is a role for treatment with and without antiepileptic drugs, but photosensitivity usually does not disappear spontaneously, and then typically in the third decade.

  15. The effects of retinal abnormalities on the multifocal visual evoked potential.

    PubMed

    Chen, John Y; Hood, Donald C; Odel, Jeffrey G; Behrens, Myles M

    2006-10-01

    To examine the effects on the amplitude and latency of the multifocal visual evoked potential (mfVEP) in retinal diseases associated with depressed multifocal electroretinograms (mfERG). Static automated perimetry (SAP), mfERGs, and mfVEPs were obtained from 15 individuals seen by neuro-ophthalmologists and diagnosed with retinal disease based on funduscopic examination, visual field, and mfERG. Optic neuropathy was ruled out in all cases. Diagnoses included autoimmune retinopathy (n = 3), branch retinal arterial occlusion (n = 3), branch retinal vein occlusion (n = 1), vitamin A deficiency (n = 1), digoxin/age-related macular degeneration (n = 1), multiple evanescent white dot syndrome (n = 1), and nonspecific retinal disease (n = 5). Patients were selected from a larger group based on abnormal mfERG amplitudes covering a diameter of 20 degrees or greater. Fourteen (93%) of 15 patients showed significant mfVEP delays, as determined by either mean latency or the probability of a cluster of delayed local responses. Thirteen of 15 patients had normal mfVEP amplitudes in regions corresponding to markedly reduced or nonrecordable mfERG responses. These findings can be mimicked in normal individuals by viewing the display through a neutral-density filter. Retinal diseases can result in mfVEPs of relatively normal amplitudes, often with delays, in regions showing decreased mfERG responses and visual field sensitivity loss. Consequently, a retinal problem can be missed, or dismissed as functional, if a diagnosis is based on an mfVEP of normal or near-normal amplitude. Further, in patients with marked mfVEP delays, a retinal problem could be confused with optic neuritis, especially in a patient with a normal appearing fundus.

  16. Retinal abnormalities in β-thalassemia major.

    PubMed

    Bhoiwala, Devang L; Dunaief, Joshua L

    2016-01-01

    Patients with beta (β)-thalassemia (β-TM: β-thalassemia major, β-TI: β-thalassemia intermedia) have a variety of complications that may affect all organs, including the eye. Ocular abnormalities include retinal pigment epithelial degeneration, angioid streaks, venous tortuosity, night blindness, visual field defects, decreased visual acuity, color vision abnormalities, and acute visual loss. Patients with β-thalassemia major are transfusion dependent and require iron chelation therapy to survive. Retinal degeneration may result from either retinal iron accumulation from transfusion-induced iron overload or retinal toxicity induced by iron chelation therapy. Some who were never treated with iron chelation therapy exhibited retinopathy, and others receiving iron chelation therapy had chelator-induced retinopathy. We will focus on retinal abnormalities present in individuals with β-thalassemia major viewed in light of new findings on the mechanisms and manifestations of retinal iron toxicity. Copyright © 2016 Elsevier Inc. All rights reserved.

  17. Neural mechanisms of oculomotor abnormalities in the infantile strabismus syndrome.

    PubMed

    Walton, Mark M G; Pallus, Adam; Fleuriet, Jérome; Mustari, Michael J; Tarczy-Hornoch, Kristina

    2017-07-01

    Infantile strabismus is characterized by numerous visual and oculomotor abnormalities. Recently nonhuman primate models of infantile strabismus have been established, with characteristics that closely match those observed in human patients. This has made it possible to study the neural basis for visual and oculomotor symptoms in infantile strabismus. In this review, we consider the available evidence for neural abnormalities in structures related to oculomotor pathways ranging from visual cortex to oculomotor nuclei. These studies provide compelling evidence that a disturbance of binocular vision during a sensitive period early in life, whatever the cause, results in a cascade of abnormalities through numerous brain areas involved in visual functions and eye movements. Copyright © 2017 the American Physiological Society.

  18. Abnormal Visual Motion Processing is not a Cause of Dyslexia

    PubMed Central

    Olulade, Olumide A.; Napoliello, Eileen M.; Eden, Guinevere F.

    2013-01-01

    SUMMARY Developmental dyslexia is a reading disorder, yet deficits also manifest in the magnocellular-dominated dorsal visual system. Uncertainty about whether visual deficits are causal or consequential to reading disability encumbers accurate identification and appropriate treatment of this common learning disability. Using fMRI, we demonstrate in typical readers a relationship between reading ability and activity in area V5/MT during visual motion processing and, as expected, also found lower V5/MT activity for dyslexic children compared to age-matched controls. However, when dyslexics were matched to younger controls on reading ability, no differences emerged, suggesting that weakness in V5/MT may not be causal to dyslexia. To further test for causality, dyslexics underwent a phonological-based reading intervention. Surprisingly, V5/MT activity increased along with intervention-driven reading gains, demonstrating that activity here is mobilized through reading. Our results provide strong evidence that visual magnocellular dysfunction is not causal to dyslexia, but may instead be consequential to impoverished reading. PMID:23746630

  19. Abnormal Fixational Eye Movements in Amblyopia.

    PubMed

    Shaikh, Aasef G; Otero-Millan, Jorge; Kumar, Priyanka; Ghasia, Fatema F

    2016-01-01

    Fixational saccades shift the foveal image to counteract visual fading related to neural adaptation. Drifts are slow eye movements between two adjacent fixational saccades. We quantified fixational saccades and asked whether their changes could be attributed to pathologic drifts seen in amblyopia, one of the most common causes of blindness in childhood. Thirty-six pediatric subjects with varying severity of amblyopia and eleven healthy age-matched controls held their gaze on a visual target. Eye movements were measured with high-resolution video-oculography during fellow eye-viewing and amblyopic eye-viewing conditions. Fixational saccades and drifts were analyzed in the amblyopic and fellow eye and compared with controls. We found an increase in the amplitude with decreased frequency of fixational saccades in children with amblyopia. These alterations in fixational eye movements correlated with the severity of their amblyopia. There was also an increase in eye position variance during drifts in amblyopes. There was no correlation between the eye position variance or the eye velocity during ocular drifts and the amplitude of subsequent fixational saccade. Our findings suggest that abnormalities in fixational saccades in amblyopia are independent of the ocular drift. This investigation of amblyopia in pediatric age group quantitatively characterizes the fixation instability. Impaired properties of fixational saccades could be the consequence of abnormal processing and reorganization of the visual system in amblyopia. Paucity in the visual feedback during amblyopic eye-viewing condition can attribute to the increased eye position variance and drift velocity.

  20. Visualizing how cancer chromosome abnormalities form in living cells

    Cancer.gov

    For the first time, scientists have directly observed events that lead to the formation of a chromosome abnormality that is often found in cancer cells. The abnormality, called a translocation, occurs when part of a chromosome breaks off and becomes attac

  1. Developmental visual perception deficits with no indications of prosopagnosia in a child with abnormal eye movements.

    PubMed

    Gilaie-Dotan, Sharon; Doron, Ravid

    2017-06-01

    Visual categories are associated with eccentricity biases in high-order visual cortex: Faces and reading with foveally-biased regions, while common objects and space with mid- and peripherally-biased regions. As face perception and reading are among the most challenging human visual skills, and are often regarded as the peak achievements of a distributed neural network supporting common objects perception, it is unclear why objects, which also rely on foveal vision to be processed, are associated with mid-peripheral rather than with a foveal bias. Here, we studied BN, a 9 y.o. boy who has normal basic-level vision, abnormal (limited) oculomotor pursuit and saccades, and shows developmental object and contour integration deficits but with no indication of prosopagnosia. Although we cannot infer causation from the data presented here, we suggest that normal pursuit and saccades could be critical for the development of contour integration and object perception. While faces and perhaps reading, when fixated upon, take up a small portion of central visual field and require only small eye movements to be properly processed, common objects typically prevail in mid-peripheral visual field and rely on longer-distance voluntary eye movements as saccades to be brought to fixation. While retinal information feeds into early visual cortex in an eccentricity orderly manner, we hypothesize that propagation of non-foveal information to mid and high-order visual cortex critically relies on circuitry involving eye movements. Limited or atypical eye movements, as in the case of BN, may hinder normal information flow to mid-eccentricity biased high-order visual cortex, adversely affecting its development and consequently inducing visual perceptual deficits predominantly for categories associated with these regions. Copyright © 2017 Elsevier Ltd. All rights reserved.

  2. Video-Game Play Induces Plasticity in the Visual System of Adults with Amblyopia

    PubMed Central

    Li, Roger W.; Ngo, Charlie; Nguyen, Jennie; Levi, Dennis M.

    2011-01-01

    Abnormal visual experience during a sensitive period of development disrupts neuronal circuitry in the visual cortex and results in abnormal spatial vision or amblyopia. Here we examined whether playing video games can induce plasticity in the visual system of adults with amblyopia. Specifically 20 adults with amblyopia (age 15–61 y; visual acuity: 20/25–20/480, with no manifest ocular disease or nystagmus) were recruited and allocated into three intervention groups: action videogame group (n = 10), non-action videogame group (n = 3), and crossover control group (n = 7). Our experiments show that playing video games (both action and non-action games) for a short period of time (40–80 h, 2 h/d) using the amblyopic eye results in a substantial improvement in a wide range of fundamental visual functions, from low-level to high-level, including visual acuity (33%), positional acuity (16%), spatial attention (37%), and stereopsis (54%). Using a cross-over experimental design (first 20 h: occlusion therapy, and the next 40 h: videogame therapy), we can conclude that the improvement cannot be explained simply by eye patching alone. We quantified the limits and the time course of visual plasticity induced by video-game experience. The recovery in visual acuity that we observed is at least 5-fold faster than would be expected from occlusion therapy in childhood amblyopia. We used positional noise and modelling to reveal the neural mechanisms underlying the visual improvements in terms of decreased spatial distortion (7%) and increased processing efficiency (33%). Our study had several limitations: small sample size, lack of randomization, and differences in numbers between groups. A large-scale randomized clinical study is needed to confirm the therapeutic value of video-game treatment in clinical situations. Nonetheless, taken as a pilot study, this work suggests that video-game play may provide important principles for treating amblyopia, and perhaps

  3. Video-game play induces plasticity in the visual system of adults with amblyopia.

    PubMed

    Li, Roger W; Ngo, Charlie; Nguyen, Jennie; Levi, Dennis M

    2011-08-01

    Abnormal visual experience during a sensitive period of development disrupts neuronal circuitry in the visual cortex and results in abnormal spatial vision or amblyopia. Here we examined whether playing video games can induce plasticity in the visual system of adults with amblyopia. Specifically 20 adults with amblyopia (age 15-61 y; visual acuity: 20/25-20/480, with no manifest ocular disease or nystagmus) were recruited and allocated into three intervention groups: action videogame group (n = 10), non-action videogame group (n = 3), and crossover control group (n = 7). Our experiments show that playing video games (both action and non-action games) for a short period of time (40-80 h, 2 h/d) using the amblyopic eye results in a substantial improvement in a wide range of fundamental visual functions, from low-level to high-level, including visual acuity (33%), positional acuity (16%), spatial attention (37%), and stereopsis (54%). Using a cross-over experimental design (first 20 h: occlusion therapy, and the next 40 h: videogame therapy), we can conclude that the improvement cannot be explained simply by eye patching alone. We quantified the limits and the time course of visual plasticity induced by video-game experience. The recovery in visual acuity that we observed is at least 5-fold faster than would be expected from occlusion therapy in childhood amblyopia. We used positional noise and modelling to reveal the neural mechanisms underlying the visual improvements in terms of decreased spatial distortion (7%) and increased processing efficiency (33%). Our study had several limitations: small sample size, lack of randomization, and differences in numbers between groups. A large-scale randomized clinical study is needed to confirm the therapeutic value of video-game treatment in clinical situations. Nonetheless, taken as a pilot study, this work suggests that video-game play may provide important principles for treating amblyopia, and perhaps other

  4. Wide-field fundus autofluorescence abnormalities and visual function in patients with cone and cone-rod dystrophies.

    PubMed

    Oishi, Maho; Oishi, Akio; Ogino, Ken; Makiyama, Yukiko; Gotoh, Norimoto; Kurimoto, Masafumi; Yoshimura, Nagahisa

    2014-05-20

    To evaluate the clinical utility of wide-field fundus autofluorescence (FAF) in patients with cone dystrophy and cone-rod dystrophy. Sixteen patients with cone dystrophy (CD) and 41 patients with cone-rod dystrophy (CRD) were recruited at one institution. The right eye of each patient was included for analysis. We obtained wide-field FAF images using a ultra-widefield retinal imaging device and measured the area of abnormal FAF. The association between the area of abnormal FAF and the results of visual acuity measurements, kinetic perimetry, and electroretinography (ERG) were investigated. The mean age of the participants was 51.4 ± 17.4 years, and the mean logarithm of the minimum angle of resolution was 1.00 ± 0.57. The area of abnormal FAF correlated with the scotoma measured by the Goldman perimetry I/4e isopter (ρ = 0.79, P < 0.001). The area also correlated with amplitudes of the rod ERG (ρ = -0.63, P < 0.001), combined ERG a-wave (ρ = -0.72, P < 0.001), combined ERG b-wave (ρ = -0.66, P < 0.001), cone ERG (ρ = -0.44, P = 0.001), and flicker ERG (ρ = -0.47, P < 0.001). The extent of abnormal FAF reflects the severity of functional impairment in patients with cone-dominant retinal dystrophies. Fundus autofluorescence measurements are useful for predicting retinal function in these patients. Copyright 2014 The Association for Research in Vision and Ophthalmology, Inc.

  5. Visual evoked potentials in patients after methanol poisoning.

    PubMed

    Urban, Pavel; Zakharov, Sergey; Diblík, Pavel; Pelclová, Daniela; Ridzoň, Petr

    2016-01-01

    We report the results of the visual evoked potentials (VEP) examination in patients after severe poisoning by methanol. The group of 47 patients (38 males and 9 females) was assembled out of persons who survived an outbreak of poisoning by the methanol adulterated alcohol beverages, which happened in the Czech Republic in 2012-2013. The visual evoked potentials examination was performed using monocular checkerboard pattern-reversal stimulation. Two criteria of abnormality were chosen: missing evoked response, and wave P1 latency > 117 ms. Non-parametric statistical methods (median, range, and the median test) were used to analyze factors influencing the VEP abnormality. The visual evoked potential was abnormal in 20 patients (43%), 5 of them had normal visual acuity on the Snellen chart. The VEP abnormality did not correlate significantly with initial serum concentrations of methanol, formic acid or lactate; however, it showed statistically significant inverse relation to the initial serum pH: the subgroup with the abnormal VEP had significantly lower median pH in comparison with the subgroup with the normal VEP (7.16 vs. 7.34, p = 0.04). The abnormality was not related to chronic alcohol abuse. The visual evoked potentials examination appeared sensitive enough to detected even subclinical impairment of the optic system. Metabolic acidosis is likely to be the key factor related to the development of visual damage induced by methanol. The examination performed with a delay of 1-9 months after the poisoning documented the situation relatively early after the event. It is considered as a baseline for the planned long-term follow-up of the patients, which will make it possible to assess the dynamics of the observed changes, their reversibility, and the occurrence of potential late sequelae. This work is available in Open Access model and licensed under a CC BY-NC 3.0 PL license.

  6. Abnormal Selective Attention Normalizes P3 Amplitudes in PDD

    ERIC Educational Resources Information Center

    Hoeksma, Marco R.; Kemner, Chantal; Kenemans, J. Leon; van Engeland, Herman

    2006-01-01

    This paper studied whether abnormal P3 amplitudes in PDD are a corollary of abnormalities in ERP components related to selective attention in visual and auditory tasks. Furthermore, this study sought to clarify possible age differences in such abnormalities. Children with PDD showed smaller P3 amplitudes than controls, but no abnormalities in…

  7. Development of Abnormality Detection System for Bathers using Ultrasonic Sensors

    NASA Astrophysics Data System (ADS)

    Ohnishi, Yosuke; Abe, Takehiko; Nambo, Hidetaka; Kimura, Haruhiko; Ogoshi, Yasuhiro

    This paper proposes an abnormality detection system for bather sitting in bathtub. Increasing number of in-bathtub drowning accidents in Japan draws attention. Behind this large number of bathing accidents, Japan's unique social and cultural background come surface. For majority of people in Japan, bathing serves purpose in deep warming up of body, relax and enjoyable time. Therefore it is the custom for the Japanese to soak in bathtub. However overexposure to hot water may cause dizziness or fainting, which is possible to cause in-bathtub drowning. For drowning prevention, the system detects bather's abnormal state using an ultrasonic sensor array. The array, which has many ultrasonic sensors, is installed on the ceiling of bathroom above bathtub. The abnormality detection system uses the following two methods: posture detection and behavior detection. The function of posture detection is to estimate the risk of drowning by monitoring bather's posture. Meanwhile, the function of behavior detection is to estimate the risk of drowning by monitoring bather's behavior. By using these methods, the system detects bathers' different state from normal. As a result of experiment with a subject in the bathtub, the system was possible to detect abnormal state using subject's posture and behavior. Therefore the system is useful for monitoring bather to prevent drowning in bathtub.

  8. Abnormal Fixational Eye Movements in Amblyopia

    PubMed Central

    Shaikh, Aasef G.; Otero-Millan, Jorge; Kumar, Priyanka; Ghasia, Fatema F.

    2016-01-01

    Purpose Fixational saccades shift the foveal image to counteract visual fading related to neural adaptation. Drifts are slow eye movements between two adjacent fixational saccades. We quantified fixational saccades and asked whether their changes could be attributed to pathologic drifts seen in amblyopia, one of the most common causes of blindness in childhood. Methods Thirty-six pediatric subjects with varying severity of amblyopia and eleven healthy age-matched controls held their gaze on a visual target. Eye movements were measured with high-resolution video-oculography during fellow eye-viewing and amblyopic eye-viewing conditions. Fixational saccades and drifts were analyzed in the amblyopic and fellow eye and compared with controls. Results We found an increase in the amplitude with decreased frequency of fixational saccades in children with amblyopia. These alterations in fixational eye movements correlated with the severity of their amblyopia. There was also an increase in eye position variance during drifts in amblyopes. There was no correlation between the eye position variance or the eye velocity during ocular drifts and the amplitude of subsequent fixational saccade. Our findings suggest that abnormalities in fixational saccades in amblyopia are independent of the ocular drift. Discussion This investigation of amblyopia in pediatric age group quantitatively characterizes the fixation instability. Impaired properties of fixational saccades could be the consequence of abnormal processing and reorganization of the visual system in amblyopia. Paucity in the visual feedback during amblyopic eye-viewing condition can attribute to the increased eye position variance and drift velocity. PMID:26930079

  9. Abnormal white matter tractography of visual pathways detected by high-angular-resolution diffusion imaging (HARDI) corresponds to visual dysfunction in cortical/cerebral visual impairment

    PubMed Central

    Bauer, Corinna M.; Heidary, Gena; Koo, Bang-Bon; Killiany, Ronald J.; Bex, Peter; Merabet, Lotfi B.

    2014-01-01

    Cortical (cerebral) visual impairment (CVI) is characterized by visual dysfunction associated with damage to the optic radiations and/or visual cortex. Typically it results from pre- or perinatal hypoxic damage to postchiasmal visual structures and pathways. The neuroanatomical basis of this condition remains poorly understood, particularly with regard to how the resulting maldevelopment of visual processing pathways relates to observations in the clinical setting. We report our investigation of 2 young adults diagnosed with CVI and visual dysfunction characterized by difficulties related to visually guided attention and visuospatial processing. Using high-angular-resolution diffusion imaging (HARDI), we characterized and compared their individual white matter projections of the extrageniculo-striate visual system with a normal-sighted control. Compared to a sighted control, both CVI cases revealed a striking reduction in association fibers, including the inferior frontal-occipital fasciculus as well as superior and inferior longitudinal fasciculi. This reduction in fibers associated with the major pathways implicated in visual processing may provide a neuroanatomical basis for the visual dysfunctions observed in these patients. PMID:25087644

  10. Enteric nervous system abnormalities are present in human necrotizing enterocolitis: potential neurotransplantation therapy

    PubMed Central

    2013-01-01

    Introduction Intestinal dysmotility following human necrotizing enterocolitis suggests that the enteric nervous system is injured during the disease. We examined human intestinal specimens to characterize the enteric nervous system injury that occurs in necrotizing enterocolitis, and then used an animal model of experimental necrotizing enterocolitis to determine whether transplantation of neural stem cells can protect the enteric nervous system from injury. Methods Human intestinal specimens resected from patients with necrotizing enterocolitis (n = 18), from control patients with bowel atresia (n = 8), and from necrotizing enterocolitis and control patients undergoing stoma closure several months later (n = 14 and n = 6 respectively) were subjected to histologic examination, immunohistochemistry, and real-time reverse-transcription polymerase chain reaction to examine the myenteric plexus structure and neurotransmitter expression. In addition, experimental necrotizing enterocolitis was induced in newborn rat pups and neurotransplantation was performed by administration of fluorescently labeled neural stem cells, with subsequent visualization of transplanted cells and determination of intestinal integrity and intestinal motility. Results There was significant enteric nervous system damage with increased enteric nervous system apoptosis, and decreased neuronal nitric oxide synthase expression in myenteric ganglia from human intestine resected for necrotizing enterocolitis compared with control intestine. Structural and functional abnormalities persisted months later at the time of stoma closure. Similar abnormalities were identified in rat pups exposed to experimental necrotizing enterocolitis. Pups receiving neural stem cell transplantation had improved enteric nervous system and intestinal integrity, differentiation of transplanted neural stem cells into functional neurons, significantly improved intestinal transit, and significantly decreased

  11. Myocardial perfusion abnormalities in asymptomatic patients with systemic lupus erythematosus

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Hosenpud, J.D.; Montanaro, A.; Hart, M.V.

    1984-08-01

    Accelerated coronary artery disease and myocardial infarction in young patients with systemic lupus erythematosus is well documented; however, the prevalence of coronary involvement is unknown. Accordingly, 26 patients with systemic lupus were selected irrespective of previous cardiac history to undergo exercise thallium-201 cardiac scintigraphy. Segmental perfusion abnormalities were present in 10 of the 26 studies (38.5 percent). Five patients had reversible defects suggesting ischemia, four patients had persistent defects consistent with scar, and one patient had both reversible and persistent defects in two areas. There was no correlation between positive thallium results and duration of disease, amount of corticosteroid treatment,more » major organ system involvement or age. Only a history of pericarditis appeared to be associated with positive thallium-201 results (p less than 0.05). It is concluded that segmental myocardial perfusion abnormalities are common in patients with systemic lupus erythematosus. Whether this reflects large-vessel coronary disease or small-vessel abnormalities remains to be determined.« less

  12. Visualizing anatomical evidences on atrioventricular conduction system for TAVI.

    PubMed

    Kawashima, Tomokazu; Sato, Fumi

    2014-06-01

    Visualizing the anatomy of the atrioventricular (AV) conduction axis substantiates that there is remarkable inter-individual variation at the macro- and microscopic levels, and that the atrioventricular bundle and left bundle branch are located more anteriorly, distally, and cranially and much closer to the aortic root complex than previously thought. The AV conduction system may therefore be compromised during implantation of a transcatheter aortic valve prosthesis, which may account for the relatively high incidence of new cardiac conduction abnormalities when conventional prosthetic valves are used. The design of the newer JenaValve® may afford advantages over more conventional valves by avoiding the high-risk implantation area and the potential for coronary ostia obstruction. Copyright © 2014 Elsevier Ireland Ltd. All rights reserved.

  13. Electroretinography and Visual Evoked Potentials in Childhood Brain Tumor Survivors.

    PubMed

    Pietilä, Sari; Lenko, Hanna L; Oja, Sakari; Koivisto, Anna-Maija; Pietilä, Timo; Mäkipernaa, Anne

    2016-07-01

    This population-based cross-sectional study evaluates the clinical value of electroretinography and visual evoked potentials in childhood brain tumor survivors. A flash electroretinography and a checkerboard reversal pattern visual evoked potential (or alternatively a flash visual evoked potential) were done for 51 survivors (age 3.8-28.7 years) after a mean follow-up time of 7.6 (1.5-15.1) years. Abnormal electroretinography was obtained in 1 case, bilaterally delayed abnormal visual evoked potentials in 22/51 (43%) cases. Nine of 25 patients with infratentorial tumor location, and altogether 12 out of 31 (39%) patients who did not have tumors involving the visual pathways, had abnormal visual evoked potentials. Abnormal electroretinographies are rarely observed, but abnormal visual evoked potentials are common even without evident anatomic lesions in the visual pathway. Bilateral changes suggest a general and possibly multifactorial toxic/adverse effect on the visual pathway. Electroretinography and visual evoked potential may have clinical and scientific value while evaluating long-term effects of childhood brain tumors and tumor treatment. © The Author(s) 2016.

  14. The Objective Identification and Quantification of Interstitial Lung Abnormalities in Smokers.

    PubMed

    Ash, Samuel Y; Harmouche, Rola; Ross, James C; Diaz, Alejandro A; Hunninghake, Gary M; Putman, Rachel K; Onieva, Jorge; Martinez, Fernando J; Choi, Augustine M; Lynch, David A; Hatabu, Hiroto; Rosas, Ivan O; Estepar, Raul San Jose; Washko, George R

    2017-08-01

    Previous investigation suggests that visually detected interstitial changes in the lung parenchyma of smokers are highly clinically relevant and predict outcomes, including death. Visual subjective analysis to detect these changes is time-consuming, insensitive to subtle changes, and requires training to enhance reproducibility. Objective detection of such changes could provide a method of disease identification without these limitations. The goal of this study was to develop and test a fully automated image processing tool to objectively identify radiographic features associated with interstitial abnormalities in the computed tomography scans of a large cohort of smokers. An automated tool that uses local histogram analysis combined with distance from the pleural surface was used to detect radiographic features consistent with interstitial lung abnormalities in computed tomography scans from 2257 individuals from the Genetic Epidemiology of COPD study, a longitudinal observational study of smokers. The sensitivity and specificity of this tool was determined based on its ability to detect the visually identified presence of these abnormalities. The tool had a sensitivity of 87.8% and a specificity of 57.5% for the detection of interstitial lung abnormalities, with a c-statistic of 0.82, and was 100% sensitive and 56.7% specific for the detection of the visual subtype of interstitial abnormalities called fibrotic parenchymal abnormalities, with a c-statistic of 0.89. In smokers, a fully automated image processing tool is able to identify those individuals who have interstitial lung abnormalities with moderate sensitivity and specificity. Copyright © 2017 The Association of University Radiologists. Published by Elsevier Inc. All rights reserved.

  15. Methods and systems for detecting abnormal digital traffic

    DOEpatents

    Goranson, Craig A [Kennewick, WA; Burnette, John R [Kennewick, WA

    2011-03-22

    Aspects of the present invention encompass methods and systems for detecting abnormal digital traffic by assigning characterizations of network behaviors according to knowledge nodes and calculating a confidence value based on the characterizations from at least one knowledge node and on weighting factors associated with the knowledge nodes. The knowledge nodes include a characterization model based on prior network information. At least one of the knowledge nodes should not be based on fixed thresholds or signatures. The confidence value includes a quantification of the degree of confidence that the network behaviors constitute abnormal network traffic.

  16. fMRI mapping of the visual system in the mouse brain with interleaved snapshot GE-EPI.

    PubMed

    Niranjan, Arun; Christie, Isabel N; Solomon, Samuel G; Wells, Jack A; Lythgoe, Mark F

    2016-10-01

    The use of functional magnetic resonance imaging (fMRI) in mice is increasingly prevalent, providing a means to non-invasively characterise functional abnormalities associated with genetic models of human diseases. The predominant stimulus used in task-based fMRI in the mouse is electrical stimulation of the paw. Task-based fMRI in mice using visual stimuli remains underexplored, despite visual stimuli being common in human fMRI studies. In this study, we map the mouse brain visual system with BOLD measurements at 9.4T using flashing light stimuli with medetomidine anaesthesia. BOLD responses were observed in the lateral geniculate nucleus, the superior colliculus and the primary visual area of the cortex, and were modulated by the flashing frequency, diffuse vs focussed light and stimulus context. Negative BOLD responses were measured in the visual cortex at 10Hz flashing frequency; but turned positive below 5Hz. In addition, the use of interleaved snapshot GE-EPI improved fMRI image quality without diminishing the temporal contrast-noise-ratio. Taken together, this work demonstrates a novel methodological protocol in which the mouse brain visual system can be non-invasively investigated using BOLD fMRI. Copyright © 2016 The Authors. Published by Elsevier Inc. All rights reserved.

  17. Abnormal uterine bleeding unrelated to structural uterine abnormalities: management in the perimenopausal period.

    PubMed

    Sabbioni, Lorenzo; Zanetti, Isabella; Orlandini, Cinzia; Petraglia, Felice; Luisi, Stefano

    2017-02-01

    Abnormal uterine bleeding (AUB) is one of the commonest health problems encountered by women and a frequent phenomenon during menopausal transition. The clinical management of AUB must follow a standardized classification system to obtain the better diagnostic pathway and the optimal therapy. The PALM-COEIN classification system has been approved by the International Federation of Gynecology and Obstetrics (FIGO); it recognizes structural causes of AUB, which can be measured visually with imaging techniques or histopathology, and non-structural entities such as coagulopathies, ovulatory dysfunctions, endometrial and iatrogenic causes and disorders not yet classified. In this review we aim to evaluate the management of nonstructural causes of AUB during the menopausal transition, when commonly women experience changes in menstrual bleeding patterns and unexpected bleedings which affect their quality of life.

  18. Visual abnormalities associated with enhanced optic nerve myelination.

    PubMed

    Yu, Minzhong; Narayanan, S Priyadarshini; Wang, Feng; Morse, Emily; Macklin, Wendy B; Peachey, Neal S

    2011-02-16

    Expression of the constitutively active serine/threonine kinase Akt in oligodendrocytes results in enhanced myelination in the CNS. Here, we have examined the effects of this Akt overexpression on optic nerve structure and on optic nerve function, assessed using the visual evoked potential (VEP). Transgenic mice have been generated with the Plp promoter driving expression of a modified form of Akt, in which aspartic acids are substituted for Thr308 and Ser473. These Plp-Akt-DD (Akt-DD) mice, and littermate controls, were studied at different ages. Optic nerves were examined anatomically at 2 and 6 months of age. At 2 months of age, optic nerves were substantially thicker in Akt-DD mice, reflecting an increase in myelination of optic nerve axons. By electron microscopy, myelin thickness was increased in Akt-DD optic nerve, with extended paranodal domains having excess paranodal loops, and the density of nodes of Ranvier was reduced, relative to control mice. We recorded VEPs in response to strobe flash ganzfeld stimuli presented after overnight dark- and light-adapted conditions at ages ranging from 1 to 10 months. It was possible to record a clear VEP from Akt-DD mice at all ages examined. At 1 month of age, VEP implicit times were somewhat shorter in Akt-DD transgenic mice than in control animals. Beyond 6months of age, VEP latencies were consistently delayed in Akt-DD transgenic mice. These abnormalities did not reflect an alteration in retinal function as there were no significant differences between ERGs obtained from control or Akt-DD transgenic mice. In young mice, the somewhat faster responses may reflect improved transmission due to increased myelination of optic nerve axons. In older mice, where the Akt-DD optic nerve is markedly thicker than control, it is remarkable that optic nerves continue to function. Copyright © 2010 Elsevier B.V. All rights reserved.

  19. Optic nerve dysfunction during gravity inversion. Visual field abnormalities.

    PubMed

    Sanborn, G E; Friberg, T R; Allen, R

    1987-06-01

    Inversion in a head-down position (gravity inversion) results in an intraocular pressure of 35 to 40 mm Hg in normal subjects. We used computerized static perimetry to measure the visual fields of normal subjects during gravity inversion. There were no visual field changes in the central 6 degrees of the visual field compared with the baseline (preinversion) values. However, when the central 30 degrees of the visual field was tested, reversible visual field defects were found in 11 of 19 eyes. We believe that the substantial elevation of intraocular pressure during gravity inversion may pose potential risks to the eyes, and we recommend that inversion for extended periods of time be avoided.

  20. Solar System Visualizations

    NASA Technical Reports Server (NTRS)

    Brown, Alison M.

    2005-01-01

    Solar System Visualization products enable scientists to compare models and measurements in new ways that enhance the scientific discovery process, enhance the information content and understanding of the science results for both science colleagues and the public, and create.visually appealing and intellectually stimulating visualization products. Missions supported include MER, MRO, and Cassini. Image products produced include pan and zoom animations of large mosaics to reveal the details of surface features and topography, animations into registered multi-resolution mosaics to provide context for microscopic images, 3D anaglyphs from left and right stereo pairs, and screen captures from video footage. Specific products include a three-part context animation of the Cassini Enceladus encounter highlighting images from 350 to 4 meter per pixel resolution; Mars Reconnaissance Orbiter screen captures illustrating various instruments during assembly and testing at the Payload Hazardous Servicing Facility at Kennedy Space Center; and an animation of Mars Exploration Rover Opportunity's 'Rub al Khali' panorama where the rover was stuck in the deep fine sand for more than a month. This task creates new visualization products that enable new science results and enhance the public's understanding of the Solar System and NASA's missions of exploration.

  1. Which visual functions depend on intermediate visual regions? Insights from a case of developmental visual form agnosia.

    PubMed

    Gilaie-Dotan, Sharon

    2016-03-01

    A key question in visual neuroscience is the causal link between specific brain areas and perceptual functions; which regions are necessary for which visual functions? While the contribution of primary visual cortex and high-level visual regions to visual perception has been extensively investigated, the contribution of intermediate visual areas (e.g. V2/V3) to visual processes remains unclear. Here I review more than 20 visual functions (early, mid, and high-level) of LG, a developmental visual agnosic and prosopagnosic young adult, whose intermediate visual regions function in a significantly abnormal fashion as revealed through extensive fMRI and ERP investigations. While expectedly, some of LG's visual functions are significantly impaired, some of his visual functions are surprisingly normal (e.g. stereopsis, color, reading, biological motion). During the period of eight-year testing described here, LG trained on a perceptual learning paradigm that was successful in improving some but not all of his visual functions. Following LG's visual performance and taking into account additional findings in the field, I propose a framework for how different visual areas contribute to different visual functions, with an emphasis on intermediate visual regions. Thus, although rewiring and plasticity in the brain can occur during development to overcome and compensate for hindering developmental factors, LG's case seems to indicate that some visual functions are much less dependent on strict hierarchical flow than others, and can develop normally in spite of abnormal mid-level visual areas, thereby probably less dependent on intermediate visual regions. Copyright © 2015 Elsevier Ltd. All rights reserved.

  2. Aircraft Abnormal Conditions Detection, Identification, and Evaluation Using Innate and Adaptive Immune Systems Interaction

    NASA Astrophysics Data System (ADS)

    Al Azzawi, Dia

    Abnormal flight conditions play a major role in aircraft accidents frequently causing loss of control. To ensure aircraft operation safety in all situations, intelligent system monitoring and adaptation must rely on accurately detecting the presence of abnormal conditions as soon as they take place, identifying their root cause(s), estimating their nature and severity, and predicting their impact on the flight envelope. Due to the complexity and multidimensionality of the aircraft system under abnormal conditions, these requirements are extremely difficult to satisfy using existing analytical and/or statistical approaches. Moreover, current methodologies have addressed only isolated classes of abnormal conditions and a reduced number of aircraft dynamic parameters within a limited region of the flight envelope. This research effort aims at developing an integrated and comprehensive framework for the aircraft abnormal conditions detection, identification, and evaluation based on the artificial immune systems paradigm, which has the capability to address the complexity and multidimensionality issues related to aircraft systems. Within the proposed framework, a novel algorithm was developed for the abnormal conditions detection problem and extended to the abnormal conditions identification and evaluation. The algorithm and its extensions were inspired from the functionality of the biological dendritic cells (an important part of the innate immune system) and their interaction with the different components of the adaptive immune system. Immunity-based methodologies for re-assessing the flight envelope at post-failure and predicting the impact of the abnormal conditions on the performance and handling qualities are also proposed and investigated in this study. The generality of the approach makes it applicable to any system. Data for artificial immune system development were collected from flight tests of a supersonic research aircraft within a motion-based flight

  3. Brain and bone abnormalities of thanatophoric dwarfism.

    PubMed

    Miller, Elka; Blaser, Susan; Shannon, Patrick; Widjaja, Elysa

    2009-01-01

    The purpose of this article is to present the imaging findings of skeletal and brain abnormalities in thanatophoric dwarfism, a lethal form of dysplastic dwarfism. The bony abnormalities associated with thanatophoric dwarfism include marked shortening of the tubular bones and ribs. Abnormal temporal lobe development is a common associated feature and can be visualized as early as the second trimester. It is important to assess the brains of fetuses with suspected thanatophoric dwarfism because the presence of associated brain malformations can assist in the antenatal diagnosis of thanatophoric dwarfism.

  4. Component-Based Visualization System

    NASA Technical Reports Server (NTRS)

    Delgado, Francisco

    2005-01-01

    A software system has been developed that gives engineers and operations personnel with no "formal" programming expertise, but who are familiar with the Microsoft Windows operating system, the ability to create visualization displays to monitor the health and performance of aircraft/spacecraft. This software system is currently supporting the X38 V201 spacecraft component/system testing and is intended to give users the ability to create, test, deploy, and certify their subsystem displays in a fraction of the time that it would take to do so using previous software and programming methods. Within the visualization system there are three major components: the developer, the deployer, and the widget set. The developer is a blank canvas with widget menu items that give users the ability to easily create displays. The deployer is an application that allows for the deployment of the displays created using the developer application. The deployer has additional functionality that the developer does not have, such as printing of displays, screen captures to files, windowing of displays, and also serves as the interface into the documentation archive and help system. The third major component is the widget set. The widgets are the visual representation of the items that will make up the display (i.e., meters, dials, buttons, numerical indicators, string indicators, and the like). This software was developed using Visual C++ and uses COTS (commercial off-the-shelf) software where possible.

  5. The SCHEIE Visual Field Grading System

    PubMed Central

    Sankar, Prithvi S.; O’Keefe, Laura; Choi, Daniel; Salowe, Rebecca; Miller-Ellis, Eydie; Lehman, Amanda; Addis, Victoria; Ramakrishnan, Meera; Natesh, Vikas; Whitehead, Gideon; Khachatryan, Naira; O’Brien, Joan

    2017-01-01

    Objective No method of grading visual field (VF) defects has been widely accepted throughout the glaucoma community. The SCHEIE (Systematic Classification of Humphrey visual fields-Easy Interpretation and Evaluation) grading system for glaucomatous visual fields was created to convey qualitative and quantitative information regarding visual field defects in an objective, reproducible, and easily applicable manner for research purposes. Methods The SCHEIE grading system is composed of a qualitative and quantitative score. The qualitative score consists of designation in one or more of the following categories: normal, central scotoma, paracentral scotoma, paracentral crescent, temporal quadrant, nasal quadrant, peripheral arcuate defect, expansive arcuate, or altitudinal defect. The quantitative component incorporates the Humphrey visual field index (VFI), location of visual defects for superior and inferior hemifields, and blind spot involvement. Accuracy and speed at grading using the qualitative and quantitative components was calculated for non-physician graders. Results Graders had a median accuracy of 96.67% for their qualitative scores and a median accuracy of 98.75% for their quantitative scores. Graders took a mean of 56 seconds per visual field to assign a qualitative score and 20 seconds per visual field to assign a quantitative score. Conclusion The SCHEIE grading system is a reproducible tool that combines qualitative and quantitative measurements to grade glaucomatous visual field defects. The system aims to standardize clinical staging and to make specific visual field defects more easily identifiable. Specific patterns of visual field loss may also be associated with genetic variants in future genetic analysis. PMID:28932621

  6. Performance of a fail-safe system to follow up abnormal mammograms in primary care.

    PubMed

    Grossman, Ellie; Phillips, Russell S; Weingart, Saul N

    2010-09-01

    Missed and delayed breast cancer diagnoses are major sources of potential harm to patients and medical malpractice liability in the United States. Follow-up of abnormal mammogram results is an essential but challenging component of safe breast care. To explore the value of an inexpensive method to follow up abnormal test results, we examined a paper-based fail-safe system. We examined a fail-safe system used to follow up abnormal mammograms at a primary care practice at an urban teaching hospital. We analyzed all abnormal mammogram reports and clinicians' responses to follow-up reminders. We characterized potential lapses identified in this system and used regression models to identify patient, provider, and test result characteristics associated with such lapses. Clinicians responded to fail-safe reminders for 92% of 948 abnormal mammograms. Clinicians reported that they were unaware of the abnormal result in 8% of cases and that there was no follow-up plan in place for 3% of cases. Clinicians with more years of experience were more likely to be aware of the abnormal result (odds of being unaware per incremental year in practice, 0.92; 95% confidence interval, 0.88-0.97) and were more likely to have a follow-up plan. A paper-based fail-safe system for abnormal mammograms is feasible in a primary care practice. However, special care is warranted to ensure full clinician adherence and address staff transitions and trainee-related issues.

  7. Lenticular abnormalities in children.

    PubMed

    Khokhar, Sudarshan; Agarwal, Tushar; Kumar, Gaurav; Kushmesh, Rakhi; Tejwani, Lalit Kumar

    2012-01-01

    To study the lenticular problems in children presenting at an apex institute. Retrospective analysis of records (< 14 years) of new lens clinic cases was done. Of 1,047 children, 687 were males. Mean age at presentation was 6.35 ± 4.13 years. Developmental cataract was seen in 45.6% and posttraumatic cataract in 29.7% of patients. Other abnormalities were cataract with retinal detachment, persistent hyperplastic primary vitreous, subluxated lens, micro/spherophakia, cataract secondary to uveitis, intraocular lens complications, cataract with choroidal coloboma, and visual axis opacification. Developmental and posttraumatic cataracts were the most common abnormalities. Delayed presentation is of concern. Copyright 2012, SLACK Incorporated.

  8. Autonomous facial recognition system inspired by human visual system based logarithmical image visualization technique

    NASA Astrophysics Data System (ADS)

    Wan, Qianwen; Panetta, Karen; Agaian, Sos

    2017-05-01

    Autonomous facial recognition system is widely used in real-life applications, such as homeland border security, law enforcement identification and authentication, and video-based surveillance analysis. Issues like low image quality, non-uniform illumination as well as variations in poses and facial expressions can impair the performance of recognition systems. To address the non-uniform illumination challenge, we present a novel robust autonomous facial recognition system inspired by the human visual system based, so called, logarithmical image visualization technique. In this paper, the proposed method, for the first time, utilizes the logarithmical image visualization technique coupled with the local binary pattern to perform discriminative feature extraction for facial recognition system. The Yale database, the Yale-B database and the ATT database are used for computer simulation accuracy and efficiency testing. The extensive computer simulation demonstrates the method's efficiency, accuracy, and robustness of illumination invariance for facial recognition.

  9. Space shuttle visual simulation system design study

    NASA Technical Reports Server (NTRS)

    1973-01-01

    A recommendation and a specification for the visual simulation system design for the space shuttle mission simulator are presented. A recommended visual system is described which most nearly meets the visual design requirements. The cost analysis of the recommended system covering design, development, manufacturing, and installation is reported. Four alternate systems are analyzed.

  10. Computer-aided detection system for chest radiography: reducing report turnaround times of examinations with abnormalities.

    PubMed

    Kao, E-Fong; Liu, Gin-Chung; Lee, Lo-Yeh; Tsai, Huei-Yi; Jaw, Twei-Shiun

    2015-06-01

    The ability to give high priority to examinations with pathological findings could be very useful to radiologists with large work lists who wish to first evaluate the most critical studies. A computer-aided detection (CAD) system for identifying chest examinations with abnormalities has therefore been developed. To evaluate the effectiveness of a CAD system on report turnaround times of chest examinations with abnormalities. The CAD system was designed to automatically mark chest examinations with possible abnormalities in the work list of radiologists interpreting chest examinations. The system evaluation was performed in two phases: two radiologists interpreted the chest examinations without CAD in phase 1 and with CAD in phase 2. The time information recorded by the radiology information system was then used to calculate the turnaround times. All chest examinations were reviewed by two other radiologists and were divided into normal and abnormal groups. The turnaround times for the examinations with pathological findings with and without the CAD system assistance were compared. The sensitivity and specificity of the CAD for chest abnormalities were 0.790 and 0.697, respectively, and use of the CAD system decreased the turnaround time for chest examinations with abnormalities by 44%. The turnaround times required for radiologists to identify chest examinations with abnormalities could be reduced by using the CAD system. This system could be useful for radiologists with large work lists who wish to first evaluate the most critical studies. © The Foundation Acta Radiologica 2014 Reprints and permissions: sagepub.co.uk/journalsPermissions.nav.

  11. [Review of visual display system in flight simulator].

    PubMed

    Xie, Guang-hui; Wei, Shao-ning

    2003-06-01

    Visual display system is the key part and plays a very important role in flight simulators and flight training devices. The developing history of visual display system is recalled and the principle and characters of some visual display systems including collimated display systems and back-projected collimated display systems are described. The future directions of visual display systems are analyzed.

  12. Visualizing Parallel Computer System Performance

    NASA Technical Reports Server (NTRS)

    Malony, Allen D.; Reed, Daniel A.

    1988-01-01

    Parallel computer systems are among the most complex of man's creations, making satisfactory performance characterization difficult. Despite this complexity, there are strong, indeed, almost irresistible, incentives to quantify parallel system performance using a single metric. The fallacy lies in succumbing to such temptations. A complete performance characterization requires not only an analysis of the system's constituent levels, it also requires both static and dynamic characterizations. Static or average behavior analysis may mask transients that dramatically alter system performance. Although the human visual system is remarkedly adept at interpreting and identifying anomalies in false color data, the importance of dynamic, visual scientific data presentation has only recently been recognized Large, complex parallel system pose equally vexing performance interpretation problems. Data from hardware and software performance monitors must be presented in ways that emphasize important events while eluding irrelevant details. Design approaches and tools for performance visualization are the subject of this paper.

  13. Relating Standardized Visual Perception Measures to Simulator Visual System Performance

    NASA Technical Reports Server (NTRS)

    Kaiser, Mary K.; Sweet, Barbara T.

    2013-01-01

    Human vision is quantified through the use of standardized clinical vision measurements. These measurements typically include visual acuity (near and far), contrast sensitivity, color vision, stereopsis (a.k.a. stereo acuity), and visual field periphery. Simulator visual system performance is specified in terms such as brightness, contrast, color depth, color gamut, gamma, resolution, and field-of-view. How do these simulator performance characteristics relate to the perceptual experience of the pilot in the simulator? In this paper, visual acuity and contrast sensitivity will be related to simulator visual system resolution, contrast, and dynamic range; similarly, color vision will be related to color depth/color gamut. Finally, we will consider how some characteristics of human vision not typically included in current clinical assessments could be used to better inform simulator requirements (e.g., relating dynamic characteristics of human vision to update rate and other temporal display characteristics).

  14. Postmortem brain abnormalities of the glutamate neurotransmitter system in autism.

    PubMed

    Purcell, A E; Jeon, O H; Zimmerman, A W; Blue, M E; Pevsner, J

    2001-11-13

    Studies examining the brains of individuals with autism have identified anatomic and pathologic changes in regions such as the cerebellum and hippocampus. Little, if anything, is known, however, about the molecules that are involved in the pathogenesis of this disorder. To identify genes with abnormal expression levels in the cerebella of subjects with autism. Brain samples from a total of 10 individuals with autism and 23 matched controls were collected, mainly from the cerebellum. Two cDNA microarray technologies were used to identify genes that were significantly up- or downregulated in autism. The abnormal mRNA or protein levels of several genes identified by microarray analysis were investigated using PCR with reverse transcription and Western blotting. alpha-Amino-3-hydroxy-5-methyl-4-isoxazoleproprionic acid (AMPA)- and NMDA-type glutamate receptor densities were examined with receptor autoradiography in the cerebellum, caudate-putamen, and prefrontal cortex. The mRNA levels of several genes were significantly increased in autism, including excitatory amino acid transporter 1 and glutamate receptor AMPA 1, two members of the glutamate system. Abnormalities in the protein or mRNA levels of several additional molecules in the glutamate system were identified on further analysis, including glutamate receptor binding proteins. AMPA-type glutamate receptor density was decreased in the cerebellum of individuals with autism (p < 0.05). Subjects with autism may have specific abnormalities in the AMPA-type glutamate receptors and glutamate transporters in the cerebellum. These abnormalities may be directly involved in the pathogenesis of the disorder.

  15. Cone Photoreceptor Abnormalities Correlate with Vision Loss in Patients with Stargardt Disease

    PubMed Central

    Chen, Yingming; Ratnam, Kavitha; Sundquist, Sanna M.; Lujan, Brandon; Ayyagari, Radha; Gudiseva, V. Harini; Roorda, Austin

    2011-01-01

    Purpose. To study the relationship between macular cone structure, fundus autofluorescence (AF), and visual function in patients with Stargardt disease (STGD). Methods. High-resolution images of the macula were obtained with adaptive optics scanning laser ophthalmoscopy (AOSLO) and spectral domain optical coherence tomography in 12 patients with STGD and 27 age-matched healthy subjects. Measures of retinal structure and AF were correlated with visual function, including best-corrected visual acuity, color vision, kinetic and static perimetry, fundus-guided microperimetry, and full-field electroretinography. Mutation analysis of the ABCA4 gene was completed in all patients. Results. Patients were 15 to 55 years old, and visual acuity ranged from 20/25–20/320. Central scotomas were present in all patients, although the fovea was spared in three patients. The earliest cone spacing abnormalities were observed in regions of homogeneous AF, normal visual function, and normal outer retinal structure. Outer retinal structure and AF were most normal near the optic disc. Longitudinal studies showed progressive increases in AF followed by reduced AF associated with losses of visual sensitivity, outer retinal layers, and cones. At least one disease-causing mutation in the ABCA4 gene was identified in 11 of 12 patients studied; 1 of 12 patients showed no disease-causing ABCA4 mutations. Conclusions. AOSLO imaging demonstrated abnormal cone spacing in regions of abnormal fundus AF and reduced visual function. These findings provide support for a model of disease progression in which lipofuscin accumulation results in homogeneously increased AF with cone spacing abnormalities, followed by heterogeneously increased AF with cone loss, then reduced AF with cone and RPE cell death. (ClinicalTrials.gov number, NCT00254605.) PMID:21296825

  16. A knowledge based system for scientific data visualization

    NASA Technical Reports Server (NTRS)

    Senay, Hikmet; Ignatius, Eve

    1992-01-01

    A knowledge-based system, called visualization tool assistant (VISTA), which was developed to assist scientists in the design of scientific data visualization techniques, is described. The system derives its knowledge from several sources which provide information about data characteristics, visualization primitives, and effective visual perception. The design methodology employed by the system is based on a sequence of transformations which decomposes a data set into a set of data partitions, maps this set of partitions to visualization primitives, and combines these primitives into a composite visualization technique design. Although the primary function of the system is to generate an effective visualization technique design for a given data set by using principles of visual perception the system also allows users to interactively modify the design, and renders the resulting image using a variety of rendering algorithms. The current version of the system primarily supports visualization techniques having applicability in earth and space sciences, although it may easily be extended to include other techniques useful in other disciplines such as computational fluid dynamics, finite-element analysis and medical imaging.

  17. Glutamatergic system abnormalities in posttraumatic stress disorder.

    PubMed

    Nishi, Daisuke; Hashimoto, Kenji; Noguchi, Hiroko; Hamazaki, Kei; Hamazaki, Tomohito; Matsuoka, Yutaka

    2015-12-01

    Accumulating evidence suggests involvement of the glutamatergic system in the biological mechanisms of posttraumatic stress disorder (PTSD), but few studies have demonstrated an association between glutamatergic system abnormalities and PTSD diagnosis or severity. We aimed to examine whether abnormalities in serum glutamate and in the glutamine/glutamate ratio were associated with PTSD diagnosis and severity in severely injured patients at risk for PTSD and major depressive disorder (MDD). This is a nested case-control study in TPOP (Tachikawa project for prevention of posttraumatic stress disorder with polyunsaturated fatty acid) trial. Diagnosis and severity of PTSD were assessed 3 months after the accidents using the Clinician-Administered PTSD Scale. The associations of glutamate levels and the glutamine/glutamate ratio with diagnosis and severity of PTSD and MDD were investigated by univariate and multiple linear regression analyses. Ninety-seven of 110 participants (88 %) completed assessments at 3 months. Serum glutamate levels were significantly higher for participants with full or partial PTSD than for participants without PTSD (p = 0.049) and for participants with MDD than for participants without MDD (p = 0.048). Multiple linear regression analyses showed serum glutamate levels were significantly positively associated with PTSD severity (p = 0.02) and MDD severity (p = 0.03). The glutamine/glutamate ratio was also significantly inversely associated with PTSD severity (p = 0.03), but not with MDD severity (p = 0.07). These findings suggest that the glutamatergic system may play a major role in the pathogenesis of PTSD and the need for new treatments targeting the glutamatergic system to be developed for PTSD.

  18. Visual system manifestations of Alzheimer's disease.

    PubMed

    Kusne, Yael; Wolf, Andrew B; Townley, Kate; Conway, Mandi; Peyman, Gholam A

    2017-12-01

    Alzheimer's disease (AD) is an increasingly common disease with massive personal and economic costs. While it has long been known that AD impacts the visual system, there has recently been an increased focus on understanding both pathophysiological mechanisms that may be shared between the eye and brain and how related biomarkers could be useful for AD diagnosis. Here, were review pertinent cellular and molecular mechanisms of AD pathophysiology, the presence of AD pathology in the visual system, associated functional changes, and potential development of diagnostic tools based on the visual system. Additionally, we discuss links between AD and visual disorders, including possible pathophysiological mechanisms and their relevance for improving our understanding of AD. © 2016 Acta Ophthalmologica Scandinavica Foundation. Published by John Wiley & Sons Ltd.

  19. Visual Network Asymmetry and Default Mode Network Function in ADHD: An fMRI Study

    PubMed Central

    Hale, T. Sigi; Kane, Andrea M.; Kaminsky, Olivia; Tung, Kelly L.; Wiley, Joshua F.; McGough, James J.; Loo, Sandra K.; Kaplan, Jonas T.

    2014-01-01

    Background: A growing body of research has identified abnormal visual information processing in attention-deficit hyperactivity disorder (ADHD). In particular, slow processing speed and increased reliance on visuo-perceptual strategies have become evident. Objective: The current study used recently developed fMRI methods to replicate and further examine abnormal rightward biased visual information processing in ADHD and to further characterize the nature of this effect; we tested its association with several large-scale distributed network systems. Method: We examined fMRI BOLD response during letter and location judgment tasks, and directly assessed visual network asymmetry and its association with large-scale networks using both a voxelwise and an averaged signal approach. Results: Initial within-group analyses revealed a pattern of left-lateralized visual cortical activity in controls but right-lateralized visual cortical activity in ADHD children. Direct analyses of visual network asymmetry confirmed atypical rightward bias in ADHD children compared to controls. This ADHD characteristic was atypically associated with reduced activation across several extra-visual networks, including the default mode network (DMN). We also found atypical associations between DMN activation and ADHD subjects’ inattentive symptoms and task performance. Conclusion: The current study demonstrated rightward VNA in ADHD during a simple letter discrimination task. This result adds an important novel consideration to the growing literature identifying abnormal visual processing in ADHD. We postulate that this characteristic reflects greater perceptual engagement of task-extraneous content, and that it may be a basic feature of less efficient top-down task-directed control over visual processing. We additionally argue that abnormal DMN function may contribute to this characteristic. PMID:25076915

  20. 47 CFR 87.483 - Audio visual warning systems.

    Code of Federal Regulations, 2014 CFR

    2014-10-01

    ... 47 Telecommunication 5 2014-10-01 2014-10-01 false Audio visual warning systems. 87.483 Section 87... AVIATION SERVICES Stations in the Radiodetermination Service § 87.483 Audio visual warning systems. An audio visual warning system (AVWS) is a radar-based obstacle avoidance system. AVWS activates...

  1. Electrophysiological evidence of altered visual processing in adults who experienced visual deprivation during infancy.

    PubMed

    Segalowitz, Sidney J; Sternin, Avital; Lewis, Terri L; Dywan, Jane; Maurer, Daphne

    2017-04-01

    We examined the role of early visual input in visual system development by testing adults who had been born with dense bilateral cataracts that blocked all patterned visual input during infancy until the cataractous lenses were removed surgically and the eyes fitted with compensatory contact lenses. Patients viewed checkerboards and textures to explore early processing regions (V1, V2), Glass patterns to examine global form processing (V4), and moving stimuli to explore global motion processing (V5). Patients' ERPs differed from those of controls in that (1) the V1 component was much smaller for all but the simplest stimuli and (2) extrastriate components did not differentiate amongst texture stimuli, Glass patterns, or motion stimuli. The results indicate that early visual deprivation contributes to permanent abnormalities at early and mid levels of visual processing, consistent with enduring behavioral deficits in the ability to process complex textures, global form, and global motion. © 2017 Wiley Periodicals, Inc.

  2. Two visual systems in monitoring of dynamic traffic: effects of visual disruption.

    PubMed

    Zheng, Xianjun Sam; McConkie, George W

    2010-05-01

    Studies from neurophysiology and neuropsychology provide support for two separate object- and location-based visual systems, ventral and dorsal. In the driving context, a study was conducted using a change detection paradigm to explore drivers' ability to monitor the dynamic traffic flow, and the effects of visual disruption on these two visual systems. While driving, a discrete change, such as vehicle location, color, or identity, was occasionally made in one of the vehicles on the road ahead of the driver. Experiment results show that without visual disruption, all changes were detected very well; yet, these equally perceivable changes were disrupted differently by a brief blank display (150 ms): the detection of location changes was especially reduced. The disruption effects were also bigger for the parked vehicle compared to the moving ones. The findings support the different roles for two visual systems in monitoring the dynamic traffic: the "where", dorsal system, tracks vehicle spatiotemporal information on perceptual level, encoding information in a coarse and transient manner; whereas the "what", ventral system, monitors vehicles' featural information, encoding information more accurately and robustly. Both systems work together contributing to the driver's situation awareness of traffic. Benefits and limitations of using the driving simulation are also discussed. Copyright (c) 2009 Elsevier Ltd. All rights reserved.

  3. Abnormal global processing along the dorsal visual pathway in autism: a possible mechanism for weak visuospatial coherence?

    PubMed

    Pellicano, Elizabeth; Gibson, Lisa; Maybery, Murray; Durkin, Kevin; Badcock, David R

    2005-01-01

    Frith and Happe (Frith, U., & Happe, F. (1994). Autism: Beyond theory of mind. Cognition, 50, 115-132) argue that individuals with autism exhibit 'weak central coherence': an inability to integrate elements of information into coherent wholes. Some authors have speculated that a high-level impairment might be present in the dorsal visual pathway in autism, and furthermore, that this might account for weak central coherence, at least at the visuospatial level. We assessed the integrity of the dorsal visual pathway in children diagnosed with an autism spectrum disorder (ASD), and in typically developing children, using two visual tasks, one examining functioning at higher levels of the dorsal cortical stream (Global Dot Motion (GDM)), and the other assessing lower-level dorsal stream functioning (Flicker Contrast Sensitivity (FCS)). Central coherence was tested using the Children's Embedded Figures Test (CEFT). Relative to the typically developing children, the children with ASD had shorter CEFT latencies and higher GDM thresholds but equivalent FCS thresholds. Additionally, CEFT latencies were inversely related to GDM thresholds in the ASD group. These outcomes indicate that the elevated global motion thresholds in autism are the result of high-level impairments in dorsal cortical regions. Weak visuospatial coherence in autism may be in the form of abnormal cooperative mechanisms in extra-striate cortical areas, which might contribute to differential performance when processing stimuli as Gestalts, including both dynamic (i.e., global motion perception) and static (i.e., disembedding performance) stimuli.

  4. Visual processing in anorexia nervosa and body dysmorphic disorder: similarities, differences, and future research directions

    PubMed Central

    Madsen, Sarah K.; Bohon, Cara; Feusner, Jamie D.

    2013-01-01

    Anorexia nervosa (AN) and body dysmorphic disorder (BDD) are psychiatric disorders that involve distortion of the experience of one’s physical appearance. In AN, individuals believe that they are overweight, perceive their body as “fat,” and are preoccupied with maintaining a low body weight. In BDD, individuals are preoccupied with misperceived defects in physical appearance, most often of the face. Distorted visual perception may contribute to these cardinal symptoms, and may be a common underlying phenotype. This review surveys the current literature on visual processing in AN and BDD, addressing lower- to higher-order stages of visual information processing and perception. We focus on peer-reviewed studies of AN and BDD that address ophthalmologic abnormalities, basic neural processing of visual input, integration of visual input with other systems, neuropsychological tests of visual processing, and representations of whole percepts (such as images of faces, bodies, and other objects). The literature suggests a pattern in both groups of over-attention to detail, reduced processing of global features, and a tendency to focus on symptom-specific details in their own images (body parts in AN, facial features in BDD), with cognitive strategy at least partially mediating the abnormalities. Visuospatial abnormalities were also evident when viewing images of others and for non-appearance related stimuli. Unfortunately no study has directly compared AN and BDD, and most studies were not designed to disentangle disease-related emotional responses from lower-order visual processing. We make recommendations for future studies to improve the understanding of visual processing abnormalities in AN and BDD. PMID:23810196

  5. Art, Illusion and the Visual System.

    ERIC Educational Resources Information Center

    Livingstone, Margaret S.

    1988-01-01

    Describes the three part system of human vision. Explores the anatomical arrangement of the vision system from the eyes to the brain. Traces the path of various visual signals to their interpretations by the brain. Discusses human visual perception and its implications in art and design. (CW)

  6. Electrophysiological abnormalities associated with extensive myelinated retinal nerve fibers.

    PubMed

    Tay, Su Ann; Sanjay, Srinivasan

    2012-07-01

    An observational case report of electrophysiological abnormalities in a patient with anisomyopic amblyopia as a result of unilateral extensive myelinated retinal nerve fibers (MNFs) is illustrated. The electrophysiological readings revealed an abnormal pattern electroretinogram (PERG) but normal full-field electroretinogram readings in the affected eye. The visual-evoked potential was also undetectable in that eye. Our findings suggest that extensive MNFs can be associated with electrophysiological abnormalities, in particular the PERG, which can aid in diagnosing the cause of impaired vision when associated with amblyopia.

  7. Electrophysiological abnormalities associated with extensive myelinated retinal nerve fibers

    PubMed Central

    Tay, Su Ann; Sanjay, Srinivasan

    2012-01-01

    An observational case report of electrophysiological abnormalities in a patient with anisomyopic amblyopia as a result of unilateral extensive myelinated retinal nerve fibers (MNFs) is illustrated. The electrophysiological readings revealed an abnormal pattern electroretinogram (PERG) but normal full-field electroretinogram readings in the affected eye. The visual-evoked potential was also undetectable in that eye. Our findings suggest that extensive MNFs can be associated with electrophysiological abnormalities, in particular the PERG, which can aid in diagnosing the cause of impaired vision when associated with amblyopia. PMID:22824610

  8. Space shuttle visual simulation system design study

    NASA Technical Reports Server (NTRS)

    1973-01-01

    The current and near-future state-of-the-art in visual simulation equipment technology is related to the requirements of the space shuttle visual system. Image source, image sensing, and displays are analyzed on a subsystem basis, and the principal conclusions are used in the formulation of a recommended baseline visual system. Perceptibility and visibility are also analyzed.

  9. The two-visual-systems hypothesis and the perspectival features of visual experience.

    PubMed

    Foley, Robert T; Whitwell, Robert L; Goodale, Melvyn A

    2015-09-01

    Some critics of the two-visual-systems hypothesis (TVSH) argue that it is incompatible with the fundamentally egocentric nature of visual experience (what we call the 'perspectival account'). The TVSH proposes that the ventral stream, which delivers up our visual experience of the world, works in an allocentric frame of reference, whereas the dorsal stream, which mediates the visual control of action, uses egocentric frames of reference. Given that the TVSH is also committed to the claim that dorsal-stream processing does not contribute to the contents of visual experience, it has been argued that the TVSH cannot account for the egocentric features of our visual experience. This argument, however, rests on a misunderstanding about how the operations mediating action and the operations mediating perception are specified in the TVSH. In this article, we emphasize the importance of the 'outputs' of the two-systems to the specification of their respective operations. We argue that once this point is appreciated, it becomes evident that the TVSH is entirely compatible with a perspectival account of visual experience. Copyright © 2015 Elsevier Inc. All rights reserved.

  10. Eye movement abnormalities in hermansky-pudlak syndrome.

    PubMed

    Gradstein, Libe; FitzGibbon, Edmond J; Tsilou, Ekaterini T; Rubin, Benjamin I; Huizing, Marjan; Gahl, William A

    2005-08-01

    Hermansky-Pudlak Syndrome (HPS) is a type of oculocutaneous albinism associated with a bleeding diathesis and pulmonary fibrosis. Although it is known that patients with HPS exhibit nystagmus, the nature of these abnormal eye movements has not been studied. Twenty-seven patients with HPS, diagnosed by platelet morphology and genetic analysis, underwent a systemic evaluation and complete eye examination. Twenty-five had eye movement recordings using magnetic search coil, infrared, or video oculography. All patients had iris transillumination, foveal hypoplasia, and variable hypopigmentation in skin and eyes. All had bleeding tendencies, and 2 reported excessive bleeding during strabismus surgery. Nine patients had pulmonary fibrosis. Visual acuities ranged from 20/20- to 20/320. Twenty patients had strabismus despite 6 having strabismus surgery previously. Ocular oscillations consistent with congenital nystagmus (CN) were clinically evident in 24 of 27 patients, and half showed periodic alternating nystagmus. In 3 patients without CN, eye movement recordings revealed minimal end-gaze nystagmus, square-wave jerks, drift during fixation and saccades, and low-gain pursuit. These patients had melanin in the posterior pole and better visual acuities than the others (P = 0.002). Most patients with HPS have CN, and many have periodic alternating nystagmus. Some have subtle eye movement abnormalities without clinically evident nystagmus, which can obscure the diagnosis, especially if hypopigmentation is mild. Absence of clinical nystagmus in a child with HPS suggests good vision. Patients with albinism, especially before surgery, should be evaluated for HPS to prevent life-threatening complications.

  11. Neurodevelopmental effects of chronic exposure to elevated levels of pro-inflammatory cytokines in a developing visual system.

    PubMed

    Lee, Ryan H; Mills, Elizabeth A; Schwartz, Neil; Bell, Mark R; Deeg, Katherine E; Ruthazer, Edward S; Marsh-Armstrong, Nicholas; Aizenman, Carlos D

    2010-01-12

    Imbalances in the regulation of pro-inflammatory cytokines have been increasingly correlated with a number of severe and prevalent neurodevelopmental disorders, including autism spectrum disorder, schizophrenia and Down syndrome. Although several studies have shown that cytokines have potent effects on neural function, their role in neural development is still poorly understood. In this study, we investigated the link between abnormal cytokine levels and neural development using the Xenopus laevis tadpole visual system, a model frequently used to examine the anatomical and functional development of neural circuits. Using a test for a visually guided behavior that requires normal visual system development, we examined the long-term effects of prolonged developmental exposure to three pro-inflammatory cytokines with known neural functions: interleukin (IL)-1beta, IL-6 and tumor necrosis factor (TNF)-alpha. We found that all cytokines affected the development of normal visually guided behavior. Neuroanatomical imaging of the visual projection showed that none of the cytokines caused any gross abnormalities in the anatomical organization of this projection, suggesting that they may be acting at the level of neuronal microcircuits. We further tested the effects of TNF-alpha on the electrophysiological properties of the retinotectal circuit and found that long-term developmental exposure to TNF-alpha resulted in enhanced spontaneous excitatory synaptic transmission in tectal neurons, increased AMPA/NMDA ratios of retinotectal synapses, and a decrease in the number of immature synapses containing only NMDA receptors, consistent with premature maturation and stabilization of these synapses. Local interconnectivity within the tectum also appeared to remain widespread, as shown by increased recurrent polysynaptic activity, and was similar to what is seen in more immature, less refined tectal circuits. TNF-alpha treatment also enhanced the overall growth of tectal cell

  12. A robust real-time abnormal region detection framework from capsule endoscopy images

    NASA Astrophysics Data System (ADS)

    Cheng, Yanfen; Liu, Xu; Li, Huiping

    2009-02-01

    In this paper we present a novel method to detect abnormal regions from capsule endoscopy images. Wireless Capsule Endoscopy (WCE) is a recent technology where a capsule with an embedded camera is swallowed by the patient to visualize the gastrointestinal tract. One challenge is one procedure of diagnosis will send out over 50,000 images, making physicians' reviewing process expensive. Physicians' reviewing process involves in identifying images containing abnormal regions (tumor, bleeding, etc) from this large number of image sequence. In this paper we construct a novel framework for robust and real-time abnormal region detection from large amount of capsule endoscopy images. The detected potential abnormal regions can be labeled out automatically to let physicians review further, therefore, reduce the overall reviewing process. In this paper we construct an abnormal region detection framework with the following advantages: 1) Trainable. Users can define and label any type of abnormal region they want to find; The abnormal regions, such as tumor, bleeding, etc., can be pre-defined and labeled using the graphical user interface tool we provided. 2) Efficient. Due to the large number of image data, the detection speed is very important. Our system can detect very efficiently at different scales due to the integral image features we used; 3) Robust. After feature selection we use a cascade of classifiers to further enforce the detection accuracy.

  13. A proposed intracortical visual prosthesis image processing system.

    PubMed

    Srivastava, N R; Troyk, P

    2005-01-01

    It has been a goal of neuroprosthesis researchers to develop a system, which could provide artifical vision to a large population of individuals with blindness. It has been demonstrated by earlier researches that stimulating the visual cortex area electrically can evoke spatial visual percepts, i.e. phosphenes. The goal of visual cortex prosthesis is to stimulate the visual cortex area and generate a visual perception in real time to restore vision. Even though the normal working of the visual system is not been completely understood, the existing knowledge has inspired research groups to develop strategies to develop visual cortex prosthesis which can help blind patients in their daily activities. A major limitation in this work is the development of an image proceessing system for converting an electronic image, as captured by a camera, into a real-time data stream for stimulation of the implanted electrodes. This paper proposes a system, which will capture the image using a camera and use a dedicated hardware real time image processor to deliver electrical pulses to intracortical electrodes. This system has to be flexible enough to adapt to individual patients and to various strategies of image reconstruction. Here we consider a preliminary architecture for this system.

  14. Complex patterns of abnormal heartbeats

    NASA Technical Reports Server (NTRS)

    Schulte-Frohlinde, Verena; Ashkenazy, Yosef; Goldberger, Ary L.; Ivanov, Plamen Ch; Costa, Madalena; Morley-Davies, Adrian; Stanley, H. Eugene; Glass, Leon

    2002-01-01

    Individuals having frequent abnormal heartbeats interspersed with normal heartbeats may be at an increased risk of sudden cardiac death. However, mechanistic understanding of such cardiac arrhythmias is limited. We present a visual and qualitative method to display statistical properties of abnormal heartbeats. We introduce dynamical "heartprints" which reveal characteristic patterns in long clinical records encompassing approximately 10(5) heartbeats and may provide information about underlying mechanisms. We test if these dynamics can be reproduced by model simulations in which abnormal heartbeats are generated (i) randomly, (ii) at a fixed time interval following a preceding normal heartbeat, or (iii) by an independent oscillator that may or may not interact with the normal heartbeat. We compare the results of these three models and test their limitations to comprehensively simulate the statistical features of selected clinical records. This work introduces methods that can be used to test mathematical models of arrhythmogenesis and to develop a new understanding of underlying electrophysiologic mechanisms of cardiac arrhythmia.

  15. Designing a visualization system for hydrological data

    NASA Astrophysics Data System (ADS)

    Fuhrmann, Sven

    2000-02-01

    The field of hydrology is, as any other scientific field, strongly affected by a massive technological evolution. The spread of modern information and communication technology within the last three decades has led to an increased collection, availability and use of spatial and temporal digital hydrological data. In a two-year research period a working group in Muenster applied and developed methods for the visualization of digital hydrological data and the documentation of hydrological models. A low-cost multimedial, hydrological visualization system (HydroVIS) for the Weser river catchment was developed. The research group designed HydroVIS under freeware constraints and tried to show what kind of multimedia visualization techniques can be effectively used with a nonprofit hydrological visualization system. The system's visual components include features such as electronic maps, temporal and nontemporal cartographic animations, the display of geologic profiles, interactive diagrams and hypertext, including photographs and tables.

  16. The Puzzle of Visual Development: Behavior and Neural Limits.

    PubMed

    Kiorpes, Lynne

    2016-11-09

    The development of visual function takes place over many months or years in primate infants. Visual sensitivity is very poor near birth and improves over different times courses for different visual functions. The neural mechanisms that underlie these processes are not well understood despite many decades of research. The puzzle arises because research into the factors that limit visual function in infants has found surprisingly mature neural organization and adult-like receptive field properties in very young infants. The high degree of visual plasticity that has been documented during the sensitive period in young children and animals leaves the brain vulnerable to abnormal visual experience. Abnormal visual experience during the sensitive period can lead to amblyopia, a developmental disorder of vision affecting ∼3% of children. This review provides a historical perspective on research into visual development and the disorder amblyopia. The mismatch between the status of the primary visual cortex and visual behavior, both during visual development and in amblyopia, is discussed, and several potential resolutions are considered. It seems likely that extrastriate visual areas further along the visual pathways may set important limits on visual function and show greater vulnerability to abnormal visual experience. Analyses based on multiunit, population activity may provide useful representations of the information being fed forward from primary visual cortex to extrastriate processing areas and to the motor output. Copyright © 2016 the authors 0270-6474/16/3611384-10$15.00/0.

  17. Solar System Visualization (SSV) Project

    NASA Technical Reports Server (NTRS)

    Todd, Jessida L.

    2005-01-01

    The Solar System Visualization (SSV) project aims at enhancing scientific and public understanding through visual representations and modeling procedures. The SSV project's objectives are to (1) create new visualization technologies, (2) organize science observations and models, and (3) visualize science results and mission Plans. The SSV project currently supports the Mars Exploration Rovers (MER) mission, the Mars Reconnaissance Orbiter (MRO), and Cassini. In support of the these missions, the SSV team has produced pan and zoom animations of large mosaics to reveal details of surface features and topography, created 3D animations of science instruments and procedures, formed 3-D anaglyphs from left and right stereo pairs, and animated registered multi-resolution mosaics to provide context for microscopic images.

  18. Abnormal Reward System Activation in Mania

    PubMed Central

    Abler, Birgit; Greenhouse, Ian; Ongur, Dost; Walter, Henrik; Heckers, Stephan

    2008-01-01

    Transmission of reward signals is a function of dopamine, a neurotransmitter known to be involved in the mechanism of psychosis. Using functional magnetic resonance imaging (fMRI), we investigated how expectation and receipt of monetary rewards modulate brain activation in patients with bipolar mania and schizophrenia. We studied 12 acutely manic patients with a history of bipolar disorder, 12 patients with a current episode of schizoaffective disorder or schizophrenia and 12 healthy subjects. All patients were treated with dopamine antagonists at the time of the study. Subjects performed a delayed incentive paradigm with monetary reward in the scanner that allowed for investigating effects of expectation, receipt, and omission of rewards. Patients with schizophrenia and healthy control subjects showed the expected activation of dopaminergic brain areas, that is, ventral tegmentum activation upon expectation of monetary rewards and nucleus accumbens activation during receipt vs omission of rewards. In manic patients, however, we did not find a similar pattern of brain activation and the differential signal in the nucleus accumbens upon receipt vs omission of rewards was significantly lower compared to the healthy control subjects. Our findings provide evidence for abnormal function of the dopamine system during receipt or omission of expected rewards in bipolar disorder. These deficits in prediction error processing in acute mania may help to explain symptoms of disinhibition and abnormal goal pursuit regulation. PMID:17987058

  19. The handicap of abnormal colour vision.

    PubMed

    Cole, Barry L

    2004-07-01

    All people with abnormal colour vision, except for a few mildly affected deuteranomals, report that they experience problems with colour in everyday life and at work. Contemporary society presents them with increasing problems because colour is now so widely used in printed materials and in computer displays. Equal opportunity law gives them protection against unfair discrimination in employment, so a decision to exclude a person from employment on the grounds of abnormal colour vision must now be well supported by good evidence and sound argument. This paper reviews the investigations that have contributed to understanding the nature and consequences of the problems they have. All those with abnormal colour vision are at a disadvantage with comparative colour tasks that involve precise matching of colours or discrimination of fine colour differences either because of their loss of colour discrimination or anomalous perception of metamers. The majority have problems when colour is used to code information, in man-made colour codes and in naturally occurring colour codes that signal ripeness of fruit, freshness of meat or illness. They can be denied the benefit of colour to mark out objects and organise complex visual displays. They may be unreliable when a colour name is used as an identifier. They are slower and less successful in search when colour is an attribute of the target object or is used to organise the visual display. Because those with the more severe forms of abnormal colour vision perceive a very limited gamut of colours, they are at a disadvantage in the pursuit and appreciation of those forms of art that use colour.

  20. Visual impairment in children with congenital Zika syndrome.

    PubMed

    Ventura, Liana O; Ventura, Camila V; Lawrence, Linda; van der Linden, Vanessa; van der Linden, Ana; Gois, Adriana L; Cavalcanti, Milena M; Barros, Eveline A; Dias, Natalia C; Berrocal, Audina M; Miller, Marilyn T

    2017-08-01

    To describe the visual impairment associated with ocular and neurological abnormalities in a cohort of children with congenital Zika syndrome (CZS). This cross-sectional study included infants with microcephaly born in Pernambuco, Brazil, from May to December 2015. Immunoglobulin M antibody capture enzyme-linked immunosorbent assay for the Zika virus on the cerebrospinal fluid samples was positive for all infants. Clinical evaluation consisted of comprehensive ophthalmologic examination including visual acuity, visual function assessment, visual developmental milestone, neurologic examination, and neuroimaging. A total of 32 infants (18 males [56%]) were included. Mean age at examination was 5.7 ± 0.9 months (range, 4-7 months). Visual function and visual developmental milestone could not be tested in 1 child (3%). Visual impairment was detected in 32 infants (100%). Retinal and/or optic nerve findings were observed in 14 patients (44%). There was no statistical difference between the patients with ocular findings and those without (P = 0.180). All patients (100%) demonstrated neurological and neuroimaging abnormalities; 3 (9%) presented with late-onset of microcephaly. Children with CZS demonstrated visual impairment regardless of retina and/or optic nerve abnormalities. This finding suggests that cortical/cerebral visual impairment may be the most common cause of blindness identified in children with CZS. Copyright © 2017 American Association for Pediatric Ophthalmology and Strabismus. Published by Elsevier Inc. All rights reserved.

  1. Characteristics of flight simulator visual systems

    NASA Technical Reports Server (NTRS)

    Statler, I. C. (Editor)

    1981-01-01

    The physical parameters of the flight simulator visual system that characterize the system and determine its fidelity are identified and defined. The characteristics of visual simulation systems are discussed in terms of the basic categories of spatial, energy, and temporal properties corresponding to the three fundamental quantities of length, mass, and time. Each of these parameters are further addressed in relation to its effect, its appropriate units or descriptors, methods of measurement, and its use or importance to image quality.

  2. ACR appropriateness criteria(®) on abnormal vaginal bleeding.

    PubMed

    Bennett, Genevieve L; Andreotti, Rochelle F; Lee, Susanna I; Dejesus Allison, Sandra O; Brown, Douglas L; Dubinsky, Theodore; Glanc, Phyllis; Mitchell, Donald G; Podrasky, Ann E; Shipp, Thomas D; Siegel, Cary Lynn; Wong-You-Cheong, Jade J; Zelop, Carolyn M

    2011-07-01

    In evaluating a woman with abnormal vaginal bleeding, imaging cannot replace definitive histologic diagnosis but often plays an important role in screening, characterization of structural abnormalities, and directing appropriate patient care. Transvaginal ultrasound (TVUS) is generally the initial imaging modality of choice, with endometrial thickness a well-established predictor of endometrial disease in postmenopausal women. Endometrial thickness measurements of ≤5 mm and ≤4 mm have been advocated as appropriate upper threshold values to reasonably exclude endometrial carcinoma in postmenopausal women with vaginal bleeding; however, the best upper threshold endometrial thickness in the asymptomatic postmenopausal patient remains a subject of debate. Endometrial thickness in a premenopausal patient is a less reliable indicator of endometrial pathology since this may vary widely depending on the phase of menstrual cycle, and an upper threshold value for normal has not been well-established. Transabdominal ultrasound is generally an adjunct to TVUS and is most helpful when TVUS is not feasible or there is poor visualization of the endometrium. Hysterosonography may also allow for better delineation of both the endometrium and focal abnormalities in the endometrial cavity, leading to hysteroscopically directed biopsy or resection. Color and pulsed Doppler may provide additional characterization of a focal endometrial abnormality by demonstrating vascularity. MRI may also serve as an important problem-solving tool if the endometrium cannot be visualized on TVUS and hysterosonography is not possible, as well as for pretreatment planning of patients with suspected endometrial carcinoma. CT is generally not warranted for the evaluation of patients with abnormal bleeding, and an abnormal endometrium incidentally detected on CT should be further evaluated with TVUS. Copyright © 2011 American College of Radiology. Published by Elsevier Inc. All rights reserved.

  3. Early detection of subclinical visual damage after blast-mediated TBI enables prevention of chronic visual deficit by treatment with P7C3-S243.

    PubMed

    Dutca, Laura M; Stasheff, Steven F; Hedberg-Buenz, Adam; Rudd, Danielle S; Batra, Nikhil; Blodi, Frederick R; Yorek, Matthew S; Yin, Terry; Shankar, Malini; Herlein, Judith A; Naidoo, Jacinth; Morlock, Lorraine; Williams, Noelle; Kardon, Randy H; Anderson, Michael G; Pieper, Andrew A; Harper, Matthew M

    2014-12-02

    Traumatic brain injury (TBI) frequently leads to chronic visual dysfunction. The purpose of this study was to investigate the effect of TBI on retinal ganglion cells (RGCs), and to test whether treatment with the novel neuroprotective compound P7C3-S243 could prevent in vivo functional deficits in the visual system. Blast-mediated TBI was modeled using an enclosed over-pressure blast chamber. The RGC physiology was evaluated using a multielectrode array and pattern electroretinogram (PERG). Histological analysis of RGC dendritic field and cell number were evaluated at the end of the study. Visual outcome measures also were evaluated based on treatment of mice with P7C3-S243 or vehicle control. We show that deficits in neutral position PERG after blast-mediated TBI occur in a temporally bimodal fashion, with temporary recovery 4 weeks after injury followed by chronically persistent dysfunction 12 weeks later. This later time point is associated with development of dendritic abnormalities and irreversible death of RGCs. We also demonstrate that ongoing pathologic processes during the temporary recovery latent period (including abnormalities of RGC physiology) lead to future dysfunction of the visual system. We report that modification of PERG to provocative postural tilt testing elicits changes in PERG measurements that correlate with a key in vitro measures of damage: the spontaneous and light-evoked activity of RGCs. Treatment with P7C3-S243 immediately after injury and throughout the temporary recovery latent period protects mice from developing chronic visual system dysfunction. Provocative PERG testing serves as a noninvasive test in the living organism to identify early damage to the visual system, which may reflect corresponding damage in the brain that is not otherwise detectable by noninvasive means. This provides the basis for developing an earlier diagnostic test to identify patients at risk for developing chronic CNS and visual system damage after TBI at

  4. Early Detection of Subclinical Visual Damage After Blast-Mediated TBI Enables Prevention of Chronic Visual Deficit by Treatment With P7C3-S243

    PubMed Central

    Dutca, Laura M.; Stasheff, Steven F.; Hedberg-Buenz, Adam; Rudd, Danielle S.; Batra, Nikhil; Blodi, Frederick R.; Yorek, Matthew S.; Yin, Terry; Shankar, Malini; Herlein, Judith A.; Naidoo, Jacinth; Morlock, Lorraine; Williams, Noelle; Kardon, Randy H.; Anderson, Michael G.; Pieper, Andrew A.; Harper, Matthew M.

    2014-01-01

    Purpose. Traumatic brain injury (TBI) frequently leads to chronic visual dysfunction. The purpose of this study was to investigate the effect of TBI on retinal ganglion cells (RGCs), and to test whether treatment with the novel neuroprotective compound P7C3-S243 could prevent in vivo functional deficits in the visual system. Methods. Blast-mediated TBI was modeled using an enclosed over-pressure blast chamber. The RGC physiology was evaluated using a multielectrode array and pattern electroretinogram (PERG). Histological analysis of RGC dendritic field and cell number were evaluated at the end of the study. Visual outcome measures also were evaluated based on treatment of mice with P7C3-S243 or vehicle control. Results. We show that deficits in neutral position PERG after blast-mediated TBI occur in a temporally bimodal fashion, with temporary recovery 4 weeks after injury followed by chronically persistent dysfunction 12 weeks later. This later time point is associated with development of dendritic abnormalities and irreversible death of RGCs. We also demonstrate that ongoing pathologic processes during the temporary recovery latent period (including abnormalities of RGC physiology) lead to future dysfunction of the visual system. We report that modification of PERG to provocative postural tilt testing elicits changes in PERG measurements that correlate with a key in vitro measures of damage: the spontaneous and light-evoked activity of RGCs. Treatment with P7C3-S243 immediately after injury and throughout the temporary recovery latent period protects mice from developing chronic visual system dysfunction. Conclusions. Provocative PERG testing serves as a noninvasive test in the living organism to identify early damage to the visual system, which may reflect corresponding damage in the brain that is not otherwise detectable by noninvasive means. This provides the basis for developing an earlier diagnostic test to identify patients at risk for developing chronic

  5. Public health nurse perceptions of Omaha System data visualization.

    PubMed

    Lee, Seonah; Kim, Era; Monsen, Karen A

    2015-10-01

    Electronic health records (EHRs) provide many benefits related to the storage, deployment, and retrieval of large amounts of patient data. However, EHRs have not fully met the need to reuse data for decision making on follow-up care plans. Visualization offers new ways to present health data, especially in EHRs. Well-designed data visualization allows clinicians to communicate information efficiently and effectively, contributing to improved interpretation of clinical data and better patient care monitoring and decision making. Public health nurse (PHN) perceptions of Omaha System data visualization prototypes for use in EHRs have not been evaluated. To visualize PHN-generated Omaha System data and assess PHN perceptions regarding the visual validity, helpfulness, usefulness, and importance of the visualizations, including interactive functionality. Time-oriented visualization for problems and outcomes and Matrix visualization for problems and interventions were developed using PHN-generated Omaha System data to help PHNs consume data and plan care at the point of care. Eleven PHNs evaluated prototype visualizations. Overall PHNs response to visualizations was positive, and feedback for improvement was provided. This study demonstrated the potential for using visualization techniques within EHRs to summarize Omaha System patient data for clinicians. Further research is needed to improve and refine these visualizations and assess the potential to incorporate visualizations within clinical EHRs. Copyright © 2015 Elsevier Ireland Ltd. All rights reserved.

  6. Diagnosing cerebral visual impairment in children with good visual acuity.

    PubMed

    van Genderen, Maria; Dekker, Marjoke; Pilon, Florine; Bals, Irmgard

    2012-06-01

    To identify elements that could facilitate the diagnosis of cerebral visual impairment (CVI) in children with good visual acuity in the general ophthalmic clinic. We retrospectively investigated the clinical characteristics of 30 children with good visual acuity and CVI and compared them with those of 23 children who were referred with a suspicion of CVI, but proved to have a different diagnosis. Clinical characteristics included medical history, MRI findings, visual acuity, crowding ratio (CR), visual field assessment, and the results of ophthalmologic and orthoptic examination. We also evaluated the additional value of a short CVI questionnaire. Eighty-three percent of the children with an abnormal medical history (mainly prematurity and perinatal hypoxia) had CVI, in contrast with none of the children with a normal medical history. Cerebral palsy, visual field defects, and partial optic atrophy only occurred in the CVI group. 41% of the children with CVI had a CR ≥2.0, which may be related to dorsal stream dysfunction. All children with CVI, but also 91% of the children without CVI gave ≥3 affirmative answers on the CVI questionnaire. An abnormal pre- or perinatal medical history is the most important risk factor for CVI in children, and therefore in deciding which children should be referred for further multidisciplinary assessment. Additional symptoms of cerebral damage, i.e., cerebral palsy, visual field defects, partial optic atrophy, and a CR ≥2 may support the diagnosis. CVI questionnaires should not be used for screening purposes as they yield too many false positives.

  7. Adaptive neuro-fuzzy and expert systems for power quality analysis and prediction of abnormal operation

    NASA Astrophysics Data System (ADS)

    Ibrahim, Wael Refaat Anis

    The present research involves the development of several fuzzy expert systems for power quality analysis and diagnosis. Intelligent systems for the prediction of abnormal system operation were also developed. The performance of all intelligent modules developed was either enhanced or completely produced through adaptive fuzzy learning techniques. Neuro-fuzzy learning is the main adaptive technique utilized. The work presents a novel approach to the interpretation of power quality from the perspective of the continuous operation of a single system. The research includes an extensive literature review pertaining to the applications of intelligent systems to power quality analysis. Basic definitions and signature events related to power quality are introduced. In addition, detailed discussions of various artificial intelligence paradigms as well as wavelet theory are included. A fuzzy-based intelligent system capable of identifying normal from abnormal operation for a given system was developed. Adaptive neuro-fuzzy learning was applied to enhance its performance. A group of fuzzy expert systems that could perform full operational diagnosis were also developed successfully. The developed systems were applied to the operational diagnosis of 3-phase induction motors and rectifier bridges. A novel approach for learning power quality waveforms and trends was developed. The technique, which is adaptive neuro fuzzy-based, learned, compressed, and stored the waveform data. The new technique was successfully tested using a wide variety of power quality signature waveforms, and using real site data. The trend-learning technique was incorporated into a fuzzy expert system that was designed to predict abnormal operation of a monitored system. The intelligent system learns and stores, in compressed format, trends leading to abnormal operation. The system then compares incoming data to the retained trends continuously. If the incoming data matches any of the learned trends, an

  8. Activity-Dependent Dysfunction in Visual and Olfactory Sensory Systems in Mouse Models of Down Syndrome

    PubMed Central

    Saqran, Lubna; Herrick, Scott P.; Frosch, Matthew P.; Hyman, Bradley T.

    2017-01-01

    Activity-dependent synaptic plasticity plays a critical role in the refinement of circuitry during postnatal development and may be disrupted in conditions that cause intellectual disability, such as Down syndrome (DS). To test this hypothesis, visual cortical plasticity was assessed in Ts65Dn mice that harbor a chromosomal duplication syntenic to human chromosome 21q. We find that Ts65Dn mice demonstrate a defect in ocular dominance plasticity (ODP) following monocular deprivation. This phenotype is similar to that of transgenic mice that express amyloid precursor protein (APP), which is duplicated in DS and in Ts65DN mice; however, normalizing APP gene copy number in Ts65Dn mice fails to rescue plasticity. Ts1Rhr mice harbor a duplication of the telomeric third of the Ts65Dn-duplicated sequence and demonstrate the same ODP defect, suggesting a gene or genes sufficient to drive the phenotype are located in that smaller duplication. In addition, we find that Ts65Dn mice demonstrate an abnormality in olfactory system connectivity, a defect in the refinement of connections to second-order neurons in the olfactory bulb. Ts1Rhr mice do not demonstrate a defect in glomerular refinement, suggesting that distinct genes or sets of genes underlie visual and olfactory system phenotypes. Importantly, these data suggest that developmental plasticity and connectivity are impaired in sensory systems in DS model mice, that such defects may contribute to functional impairment in DS, and that these phenotypes, present in male and female mice, provide novel means for examining the genetic and molecular bases for neurodevelopmental impairment in model mice in vivo. SIGNIFICANCE STATEMENT Our understanding of the basis for intellectual impairment in Down syndrome is hindered by the large number of genes duplicated in Trisomy 21 and a lack of understanding of the effect of disease pathology on the function of neural circuits in vivo. This work describes early postnatal developmental

  9. Visual recognition and visually guided action after early bilateral lesion of occipital cortex: a behavioral study of a 4.6-year-old girl.

    PubMed

    Amicuzi, Ileana; Stortini, Massimo; Petrarca, Maurizio; Di Giulio, Paola; Di Rosa, Giuseppe; Fariello, Giuseppe; Longo, Daniela; Cannatà, Vittorio; Genovese, Elisabetta; Castelli, Enrico

    2006-10-01

    We report the case of a 4.6-year-old girl born pre-term with early bilateral occipital damage. It was revealed that the child had non-severely impaired basic visual abilities and ocular motility, a selective perceptual deficit of figure-ground segregation, impaired visual recognition and abnormal navigating through space. Even if the child's visual functioning was not optimal, this was the expression of adaptive anatomic and functional brain modifications that occurred following the early lesion. Anatomic brain structure was studied with anatomic MRI and Diffusor Tensor Imaging (DTI)-MRI. This behavioral study may provide an important contribution to understanding the impact of an early lesion of the visual system on the development of visual functions and on the immature brain's potential for reorganisation related to when the damage occurred.

  10. Detecting Visually Observable Disease Symptoms from Faces.

    PubMed

    Wang, Kuan; Luo, Jiebo

    2016-12-01

    Recent years have witnessed an increasing interest in the application of machine learning to clinical informatics and healthcare systems. A significant amount of research has been done on healthcare systems based on supervised learning. In this study, we present a generalized solution to detect visually observable symptoms on faces using semi-supervised anomaly detection combined with machine vision algorithms. We rely on the disease-related statistical facts to detect abnormalities and classify them into multiple categories to narrow down the possible medical reasons of detecting. Our method is in contrast with most existing approaches, which are limited by the availability of labeled training data required for supervised learning, and therefore offers the major advantage of flagging any unusual and visually observable symptoms.

  11. Retinal and visual system: occupational and environmental toxicology.

    PubMed

    Fox, Donald A

    2015-01-01

    Occupational chemical exposure often results in sensory systems alterations that occur without other clinical signs or symptoms. Approximately 3000 chemicals are toxic to the retina and central visual system. Their dysfunction can have immediate, long-term, and delayed effects on mental health, physical health, and performance and lead to increased occupational injuries. The aims of this chapter are fourfold. First, provide references on retinal/visual system structure, function, and assessment techniques. Second, discuss the retinal features that make it especially vulnerable to toxic chemicals. Third, review the clinical and corresponding experimental data regarding retinal/visual system deficits produced by occupational toxicants: organic solvents (carbon disulfide, trichloroethylene, tetrachloroethylene, styrene, toluene, and mixtures) and metals (inorganic lead, methyl mercury, and mercury vapor). Fourth, discuss occupational and environmental toxicants as risk factors for late-onset retinal diseases and degeneration. Overall, the toxicants altered color vision, rod- and/or cone-mediated electroretinograms, visual fields, spatial contrast sensitivity, and/or retinal thickness. The findings elucidate the importance of conducting multimodal noninvasive clinical, electrophysiologic, imaging and vision testing to monitor toxicant-exposed workers for possible retinal/visual system alterations. Finally, since the retina is a window into the brain, an increased awareness and understanding of retinal/visual system dysfunction should provide additional insight into acquired neurodegenerative disorders. © 2015 Elsevier B.V. All rights reserved.

  12. A survey of visualization systems for network security.

    PubMed

    Shiravi, Hadi; Shiravi, Ali; Ghorbani, Ali A

    2012-08-01

    Security Visualization is a very young term. It expresses the idea that common visualization techniques have been designed for use cases that are not supportive of security-related data, demanding novel techniques fine tuned for the purpose of thorough analysis. Significant amount of work has been published in this area, but little work has been done to study this emerging visualization discipline. We offer a comprehensive review of network security visualization and provide a taxonomy in the form of five use-case classes encompassing nearly all recent works in this area. We outline the incorporated visualization techniques and data sources and provide an informative table to display our findings. From the analysis of these systems, we examine issues and concerns regarding network security visualization and provide guidelines and directions for future researchers and visual system developers.

  13. A novel framework for intelligent surveillance system based on abnormal human activity detection in academic environments.

    PubMed

    Al-Nawashi, Malek; Al-Hazaimeh, Obaida M; Saraee, Mohamad

    2017-01-01

    Abnormal activity detection plays a crucial role in surveillance applications, and a surveillance system that can perform robustly in an academic environment has become an urgent need. In this paper, we propose a novel framework for an automatic real-time video-based surveillance system which can simultaneously perform the tracking, semantic scene learning, and abnormality detection in an academic environment. To develop our system, we have divided the work into three phases: preprocessing phase, abnormal human activity detection phase, and content-based image retrieval phase. For motion object detection, we used the temporal-differencing algorithm and then located the motions region using the Gaussian function. Furthermore, the shape model based on OMEGA equation was used as a filter for the detected objects (i.e., human and non-human). For object activities analysis, we evaluated and analyzed the human activities of the detected objects. We classified the human activities into two groups: normal activities and abnormal activities based on the support vector machine. The machine then provides an automatic warning in case of abnormal human activities. It also embeds a method to retrieve the detected object from the database for object recognition and identification using content-based image retrieval. Finally, a software-based simulation using MATLAB was performed and the results of the conducted experiments showed an excellent surveillance system that can simultaneously perform the tracking, semantic scene learning, and abnormality detection in an academic environment with no human intervention.

  14. Using Visualization in Cockpit Decision Support Systems

    NASA Technical Reports Server (NTRS)

    Aragon, Cecilia R.

    2005-01-01

    In order to safely operate their aircraft, pilots must make rapid decisions based on integrating and processing large amounts of heterogeneous information. Visual displays are often the most efficient method of presenting safety-critical data to pilots in real time. However, care must be taken to ensure the pilot is provided with the appropriate amount of information to make effective decisions and not become cognitively overloaded. The results of two usability studies of a prototype airflow hazard visualization cockpit decision support system are summarized. The studies demonstrate that such a system significantly improves the performance of helicopter pilots landing under turbulent conditions. Based on these results, design principles and implications for cockpit decision support systems using visualization are presented.

  15. Should we add visual acuity ratios to referral criteria for potential cerebral visual impairment?

    PubMed

    van der Zee, Ymie J; Stiers, Peter; Evenhuis, Heleen M

    To determine whether the assessment of visual acuity ratios might improve the referral of children with (sub)normal visual acuity but at risk of cerebral visual impairment. In an exploratory study, we assessed visual acuity, crowding ratio and the ratios between grating acuity (Teller Acuity Cards-II) and optotype acuity (Cambridge Crowding Cards) in 60 typically developing school children (mean age 5y8m±1y1m), 21 children with ocular abnormalities only (5y7m±1y9m) and 26 children with (suspected) brain damage (5y7m±1y11m). Sensitivities and specificities were calculated for targets and controls from the perspective of different groups of diagnosticians: youth health care professionals (target: children with any visual abnormalities), ophthalmologists and low vision experts (target: children at risk of cerebral visual impairment). For youth health care professionals subnormal visual acuity had the best sensitivity (76%) and specificity (70%). For ophthalmologists and low vision experts the crowding ratio had the best sensitivity (67%) and specificity (79 and 86%). Youth health care professionals best continue applying subnormal visual acuity for screening, whereas ophthalmologists and low vision experts best add the crowding ratio to their routine diagnostics, to distinguish children at risk of visual impairment in the context of brain damage from children with ocular pathology only. Copyright © 2016 Spanish General Council of Optometry. Published by Elsevier España, S.L.U. All rights reserved.

  16. Neurodevelopmental effects of chronic exposure to elevated levels of pro-inflammatory cytokines in a developing visual system

    PubMed Central

    2010-01-01

    Background Imbalances in the regulation of pro-inflammatory cytokines have been increasingly correlated with a number of severe and prevalent neurodevelopmental disorders, including autism spectrum disorder, schizophrenia and Down syndrome. Although several studies have shown that cytokines have potent effects on neural function, their role in neural development is still poorly understood. In this study, we investigated the link between abnormal cytokine levels and neural development using the Xenopus laevis tadpole visual system, a model frequently used to examine the anatomical and functional development of neural circuits. Results Using a test for a visually guided behavior that requires normal visual system development, we examined the long-term effects of prolonged developmental exposure to three pro-inflammatory cytokines with known neural functions: interleukin (IL)-1β, IL-6 and tumor necrosis factor (TNF)-α. We found that all cytokines affected the development of normal visually guided behavior. Neuroanatomical imaging of the visual projection showed that none of the cytokines caused any gross abnormalities in the anatomical organization of this projection, suggesting that they may be acting at the level of neuronal microcircuits. We further tested the effects of TNF-α on the electrophysiological properties of the retinotectal circuit and found that long-term developmental exposure to TNF-α resulted in enhanced spontaneous excitatory synaptic transmission in tectal neurons, increased AMPA/NMDA ratios of retinotectal synapses, and a decrease in the number of immature synapses containing only NMDA receptors, consistent with premature maturation and stabilization of these synapses. Local interconnectivity within the tectum also appeared to remain widespread, as shown by increased recurrent polysynaptic activity, and was similar to what is seen in more immature, less refined tectal circuits. TNF-α treatment also enhanced the overall growth of tectal cell

  17. Three-dimensional brain growth abnormalities in childhood-onset schizophrenia visualized by using tensor-based morphometry.

    PubMed

    Gogtay, Nitin; Lu, Allen; Leow, Alex D; Klunder, Andrea D; Lee, Agatha D; Chavez, Alex; Greenstein, Deanna; Giedd, Jay N; Toga, Arthur W; Rapoport, Judith L; Thompson, Paul M

    2008-10-14

    Earlier studies revealed progressive cortical gray matter (GM) loss in childhood-onset schizophrenia (COS) across both lateral and medial surfaces of the developing brain. Here, we use tensor-based morphometry to visualize white matter (WM) growth abnormalities in COS throughout the brain. Using high-dimensional elastic image registration, we compared 3D maps of local WM growth rates in COS patients and healthy children over a 5-year period, based on analyzing longitudinal brain MRIs from 12 COS patients and 12 healthy controls matched for age, gender, and scan interval. COS patients showed up to 2.2% slower growth rates per year than healthy controls in WM (P = 0.02, all P values corrected). The greatest differences were in the right hemisphere (P = 0.006). This asymmetry was attributable to a right slower than left hemisphere growth rate mapped in COS patients (P = 0.037) but not in healthy controls. WM growth rates reached 2.6% per year in healthy controls (P = 0.0002). COS patients showed only a 1.3% per year trend for growth in the left hemisphere (P = 0.066). In COS, WM growth rates were associated with improvement in the Children's Global Assessment Scale (R = 0.64, P = 0.029). Growth rates were reduced throughout the brain in COS, but this process appeared to progress in a front-to-back (frontal-parietal) fashion, and this effect was not attributable to lower IQ. Growth rates were correlated with functional prognosis and were visualized as detailed 3D maps. Finally, these findings also confirm that the progressive GM deficits seen in schizophrenia are not the result of WM overgrowth.

  18. Comparison of multifocal visual evoked potential, standard automated perimetry and optical coherence tomography in assessing visual pathway in multiple sclerosis patients

    PubMed Central

    Laron, Michal; Cheng, Han; Zhang, Bin; Schiffman, Jade S.; Tang, Rosa A.; Frishman, Laura J.

    2010-01-01

    Background Multifocal visual evoked potentials (mfVEP) measure local response amplitude and latency in the field of vision Objective To compare the sensitivity of mfVEP, Humphrey visual field (HVF) and optical coherence tomography (OCT) in detecting visual abnormality in multiple sclerosis (MS) patients. Methods MfVEP, HVF, and OCT (retinal nerve fiber layer [RNFL]) were performed in 47 MS-ON eyes (last optic neuritis (ON) attack ≥ 6 months prior) and 65 MS-no-ON eyes without ON history. Criteria to define an eye as abnormal were: mfVEP 1) amplitude/latency: either amplitude or latency probability plots meeting cluster criteria with 95% specificity 2) amplitude or latency alone (specificity: 97% and 98%, respectively); HVF and OCT, mean deviation and RNFL thickness meeting p < 0.05, respectively. Results MfVEP (amplitude/latency) identified more abnormality in MS-ON eyes (89%) than HVF (72%), OCT (62%), mfVEP amplitude (66%) or latency (67%) alone. 18% of MS-no-ON eyes were abnormal for both mfVEP (amplitude/latency) and HVF compared to 8% with OCT. Agreement between tests ranged from 60% to 79%. MfVEP (amplitude/latency) categorized an additional 15% of MS-ON eyes as abnormal compared to HVF and OCT combined. Conclusions MfVEP, which detects both demyelination (increased latency) and neural degeneration (reduced amplitude) revealed more abnormality than HVF or OCT in MS patients. PMID:20207786

  19. 40 CFR 202.22 - Visual exhaust system inspection.

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... 40 Protection of Environment 26 2013-07-01 2013-07-01 false Visual exhaust system inspection. 202... Standards § 202.22 Visual exhaust system inspection. No motor carrier subject to these regulations shall operate any motor vehicle of a type to which this regulation is applicable unless the exhaust system of...

  20. 40 CFR 202.22 - Visual exhaust system inspection.

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... 40 Protection of Environment 26 2012-07-01 2011-07-01 true Visual exhaust system inspection. 202... Standards § 202.22 Visual exhaust system inspection. No motor carrier subject to these regulations shall operate any motor vehicle of a type to which this regulation is applicable unless the exhaust system of...

  1. 40 CFR 202.22 - Visual exhaust system inspection.

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... 40 Protection of Environment 25 2011-07-01 2011-07-01 false Visual exhaust system inspection. 202... Standards § 202.22 Visual exhaust system inspection. No motor carrier subject to these regulations shall operate any motor vehicle of a type to which this regulation is applicable unless the exhaust system of...

  2. Visualizing Terrestrial and Aquatic Systems in 3D

    EPA Science Inventory

    The need for better visualization tools for environmental science is well documented, and the Visualization for Terrestrial and Aquatic Systems project (VISTAS) aims to both help scientists produce effective environmental science visualizations and to determine which visualizatio...

  3. Interactive Learning System "VisMis" for Scientific Visualization Course

    ERIC Educational Resources Information Center

    Zhu, Xiaoming; Sun, Bo; Luo, Yanlin

    2018-01-01

    Now visualization courses have been taught at universities around the world. Keeping students motivated and actively engaged in this course can be a challenging task. In this paper we introduce our developed interactive learning system called VisMis (Visualization and Multi-modal Interaction System) for postgraduate scientific visualization course…

  4. When viewing natural scenes, do abnormal colors impact on spatial or temporal parameters of eye movements?

    PubMed

    Ho-Phuoc, Tien; Guyader, Nathalie; Landragin, Frédéric; Guérin-Dugué, Anne

    2012-02-03

    Since Treisman's theory, it has been generally accepted that color is an elementary feature that guides eye movements when looking at natural scenes. Hence, most computational models of visual attention predict eye movements using color as an important visual feature. In this paper, using experimental data, we show that color does not affect where observers look when viewing natural scene images. Neither colors nor abnormal colors modify observers' fixation locations when compared to the same scenes in grayscale. In the same way, we did not find any significant difference between the scanpaths under grayscale, color, or abnormal color viewing conditions. However, we observed a decrease in fixation duration for color and abnormal color, and this was particularly true at the beginning of scene exploration. Finally, we found that abnormal color modifies saccade amplitude distribution.

  5. A Forest Landscape Visualization System

    Treesearch

    Tim McDonald; Bryce Stokes

    1998-01-01

    A forest landscape visualization system was developed and used in creating realistic images depicting how an area might appear if harvested. The system uses a ray-tracing renderer to draw model trees on a virtual landscape. The system includes components to create landscape surfaces from digital elevation data, populate/cut trees within (polygonal) areas, and convert...

  6. Specialized Computer Systems for Environment Visualization

    NASA Astrophysics Data System (ADS)

    Al-Oraiqat, Anas M.; Bashkov, Evgeniy A.; Zori, Sergii A.

    2018-06-01

    The need for real time image generation of landscapes arises in various fields as part of tasks solved by virtual and augmented reality systems, as well as geographic information systems. Such systems provide opportunities for collecting, storing, analyzing and graphically visualizing geographic data. Algorithmic and hardware software tools for increasing the realism and efficiency of the environment visualization in 3D visualization systems are proposed. This paper discusses a modified path tracing algorithm with a two-level hierarchy of bounding volumes and finding intersections with Axis-Aligned Bounding Box. The proposed algorithm eliminates the branching and hence makes the algorithm more suitable to be implemented on the multi-threaded CPU and GPU. A modified ROAM algorithm is used to solve the qualitative visualization of reliefs' problems and landscapes. The algorithm is implemented on parallel systems—cluster and Compute Unified Device Architecture-networks. Results show that the implementation on MPI clusters is more efficient than Graphics Processing Unit/Graphics Processing Clusters and allows real-time synthesis. The organization and algorithms of the parallel GPU system for the 3D pseudo stereo image/video synthesis are proposed. With realizing possibility analysis on a parallel GPU-architecture of each stage, 3D pseudo stereo synthesis is performed. An experimental prototype of a specialized hardware-software system 3D pseudo stereo imaging and video was developed on the CPU/GPU. The experimental results show that the proposed adaptation of 3D pseudo stereo imaging to the architecture of GPU-systems is efficient. Also it accelerates the computational procedures of 3D pseudo-stereo synthesis for the anaglyph and anamorphic formats of the 3D stereo frame without performing optimization procedures. The acceleration is on average 11 and 54 times for test GPUs.

  7. Defining the cortical visual systems: "what", "where", and "how"

    NASA Technical Reports Server (NTRS)

    Creem, S. H.; Proffitt, D. R.; Kaiser, M. K. (Principal Investigator)

    2001-01-01

    The visual system historically has been defined as consisting of at least two broad subsystems subserving object and spatial vision. These visual processing streams have been organized both structurally as two distinct pathways in the brain, and functionally for the types of tasks that they mediate. The classic definition by Ungerleider and Mishkin labeled a ventral "what" stream to process object information and a dorsal "where" stream to process spatial information. More recently, Goodale and Milner redefined the two visual systems with a focus on the different ways in which visual information is transformed for different goals. They relabeled the dorsal stream as a "how" system for transforming visual information using an egocentric frame of reference in preparation for direct action. This paper reviews recent research from psychophysics, neurophysiology, neuropsychology and neuroimaging to define the roles of the ventral and dorsal visual processing streams. We discuss a possible solution that allows for both "where" and "how" systems that are functionally and structurally organized within the posterior parietal lobe.

  8. Visualizing complex (hydrological) systems with correlation matrices

    NASA Astrophysics Data System (ADS)

    Haas, J. C.

    2016-12-01

    When trying to understand or visualize the connections of different aspects of a complex system, this often requires deeper understanding to start with, or - in the case of geo data - complicated GIS software. To our knowledge, correlation matrices have rarely been used in hydrology (e.g. Stoll et al., 2011; van Loon and Laaha, 2015), yet they do provide an interesting option for data visualization and analysis. We present a simple, python based way - using a river catchment as an example - to visualize correlations and similarities in an easy and colorful way. We apply existing and easy to use python packages from various disciplines not necessarily linked to the Earth sciences and can thus quickly show how different aquifers work or react, and identify outliers, enabling this system to also be used for quality control of large datasets. Going beyond earlier work, we add a temporal and spatial element, enabling us to visualize how a system reacts to local phenomena such as for example a river, or changes over time, by visualizing the passing of time in an animated movie. References: van Loon, A.F., Laaha, G.: Hydrological drought severity explained by climate and catchment characteristics, Journal of Hydrology 526, 3-14, 2015, Drought processes, modeling, and mitigation Stoll, S., Hendricks Franssen, H. J., Barthel, R., Kinzelbach, W.: What can we learn from long-term groundwater data to improve climate change impact studies?, Hydrology and Earth System Sciences 15(12), 3861-3875, 2011

  9. A systematic review of visual processing and associated treatments in body dysmorphic disorder.

    PubMed

    Beilharz, F; Castle, D J; Grace, S; Rossell, S L

    2017-07-01

    Recent advances in body dysmorphic disorder (BDD) have explored abnormal visual processing, yet it is unclear how this relates to treatment. The aim of this study was to summarize our current understanding of visual processing in BDD and review associated treatments. The literature was collected through PsycInfo and PubMed. Visual processing articles were included if written in English after 1970, had a specific BDD group compared to healthy controls and were not case studies. Due to the lack of research regarding treatments associated with visual processing, case studies were included. A number of visual processing abnormalities are present in BDD, including face recognition, emotion identification, aesthetics, object recognition and gestalt processing. Differences to healthy controls include a dominance of detailed local processing over global processing and associated changes in brain activation in visual regions. Perceptual mirror retraining and some forms of self-exposure have demonstrated improved treatment outcomes, but have not been examined in isolation from broader treatments. Despite these abnormalities in perception, particularly concerning face and emotion recognition, few BDD treatments attempt to specifically remediate this. The development of a novel visual training programme which addresses these widespread abnormalities may provide an effective treatment modality. © 2017 John Wiley & Sons A/S. Published by John Wiley & Sons Ltd.

  10. 3D PATTERN OF BRAIN ABNORMALITIES IN FRAGILE X SYNDROME VISUALIZED USING TENSOR-BASED MORPHOMETRY

    PubMed Central

    Lee, Agatha D.; Leow, Alex D.; Lu, Allen; Reiss, Allan L.; Hall, Scott; Chiang, Ming-Chang; Toga, Arthur W.; Thompson, Paul M.

    2007-01-01

    Fragile X syndrome (FraX), a genetic neurodevelopmental disorder, results in impaired cognition with particular deficits in executive function and visuo-spatial skills. Here we report the first detailed 3D maps of the effects of the Fragile X mutation on brain structure, using tensor-based morphometry. TBM visualizes structural brain deficits automatically, without time-consuming specification of regions-of-interest. We compared 36 subjects with FraX (age: 14.66+/−1.58SD, 18 females/18 males), and 33 age-matched healthy controls (age: 14.67+/−2.2SD, 17 females/16 males), using high-dimensional elastic image registration. All 69 subjects' 3D T1-weighted brain MRIs were spatially deformed to match a high-resolution single-subject average MRI scan in ICBM space, whose geometry was optimized to produce a minimal deformation target. Maps of the local Jacobian determinant (expansion factor) were computed from the deformation fields. Statistical maps showed increased caudate (10% higher; p=0.001) and lateral ventricle volumes (19% higher; p=0.003), and trend-level parietal and temporal white matter excesses (10% higher locally; p=0.04). In affected females, volume abnormalities correlated with reduction in systemically measured levels of the fragile X mental retardation protein (FMRP; Spearman's r<−0.5 locally). Decreased FMRP correlated with ventricular expansion (p=0.042; permutation test), and anterior cingulate tissue reductions (p=0.0026; permutation test) supporting theories that FMRP is required for normal dendritic pruning in fronto-striatal-limbic pathways. No sex differences were found; findings were confirmed using traditional volumetric measures in regions of interest. Deficit patterns were replicated using Lie group statistics optimized for tensor-valued data. Investigation of how these anomalies emerge over time will accelerate our understanding of FraX and its treatment. PMID:17161622

  11. Biochemical abnormalities in neonatal seizures.

    PubMed

    Sood, Arvind; Grover, Neelam; Sharma, Roshan

    2003-03-01

    The presence of seizure does not constitute a diagnoses but it is a symptom of an underlying central nervous system disorder due to systemic or biochemical disturbances. Biochemical disturbances occur frequently in the neonatal seizures either as an underlying cause or as an associated abnormality. In their presence, it is difficult to control seizure and there is a risk of further brain damage. Early recognition and treatment of biochemical disturbances is essential for optimal management and satisfactory long term outcome. The present study was conducted in the department of pediatrics in IGMC Shimla on 59 neonates. Biochemical abnormalities were detected in 29 (49.15%) of cases. Primary metabolic abnormalities occurred in 10(16.94%) cases of neonatal seizures, most common being hypocalcaemia followed by hypoglycemia, other metabolic abnormalities include hypomagnesaemia and hyponateremia. Biochemical abnormalities were seen in 19(38.77%) cases of non metabolic seizure in neonates. Associated metabolic abnormalities were observed more often with Hypoxic-ischemic-encephalopathy (11 out of 19) cases and hypoglycemia was most common in this group. No infant had hyponateremia, hyperkelemia or low zinc level.

  12. TOPICAL REVIEW: Prosthetic interfaces with the visual system: biological issues

    NASA Astrophysics Data System (ADS)

    Cohen, Ethan D.

    2007-06-01

    The design of effective visual prostheses for the blind represents a challenge for biomedical engineers and neuroscientists. Significant progress has been made in the miniaturization and processing power of prosthesis electronics; however development lags in the design and construction of effective machine brain interfaces with visual system neurons. This review summarizes what has been learned about stimulating neurons in the human and primate retina, lateral geniculate nucleus and visual cortex. Each level of the visual system presents unique challenges for neural interface design. Blind patients with the retinal degenerative disease retinitis pigmentosa (RP) are a common population in clinical trials of visual prostheses. The visual performance abilities of normals and RP patients are compared. To generate pattern vision in blind patients, the visual prosthetic interface must effectively stimulate the retinotopically organized neurons in the central visual field to elicit patterned visual percepts. The development of more biologically compatible methods of stimulating visual system neurons is critical to the development of finer spatial percepts. Prosthesis electrode arrays need to adapt to different optimal stimulus locations, stimulus patterns, and patient disease states.

  13. Five-dimensional ultrasound system for soft tissue visualization.

    PubMed

    Deshmukh, Nishikant P; Caban, Jesus J; Taylor, Russell H; Hager, Gregory D; Boctor, Emad M

    2015-12-01

    A five-dimensional ultrasound (US) system is proposed as a real-time pipeline involving fusion of 3D B-mode data with the 3D ultrasound elastography (USE) data as well as visualization of these fused data and a real-time update capability over time for each consecutive scan. 3D B-mode data assist in visualizing the anatomy of the target organ, and 3D elastography data adds strain information. We investigate the feasibility of such a system and show that an end-to-end real-time system, from acquisition to visualization, can be developed. We present a system that consists of (a) a real-time 3D elastography algorithm based on a normalized cross-correlation (NCC) computation on a GPU; (b) real-time 3D B-mode acquisition and network transfer; (c) scan conversion of 3D elastography and B-mode volumes (if acquired by 4D wobbler probe); and (d) visualization software that fuses, visualizes, and updates 3D B-mode and 3D elastography data in real time. We achieved a speed improvement of 4.45-fold for the threaded version of the NCC-based 3D USE versus the non-threaded version. The maximum speed was 79 volumes/s for 3D scan conversion. In a phantom, we validated the dimensions of a 2.2-cm-diameter sphere scan-converted to B-mode volume. Also, we validated the 5D US system visualization transfer function and detected 1- and 2-cm spherical objects (phantom lesion). Finally, we applied the system to a phantom consisting of three lesions to delineate the lesions from the surrounding background regions of the phantom. A 5D US system is achievable with real-time performance. We can distinguish between hard and soft areas in a phantom using the transfer functions.

  14. Information processing in the primate visual system - An integrated systems perspective

    NASA Technical Reports Server (NTRS)

    Van Essen, David C.; Anderson, Charles H.; Felleman, Daniel J.

    1992-01-01

    The primate visual system contains dozens of distinct areas in the cerebral cortex and several major subcortical structures. These subdivisions are extensively interconnected in a distributed hierarchical network that contains several intertwined processing streams. A number of strategies are used for efficient information processing within this hierarchy. These include linear and nonlinear filtering, passage through information bottlenecks, and coordinated use of multiple types of information. In addition, dynamic regulation of information flow within and between visual areas may provide the computational flexibility needed for the visual system to perform a broad spectrum of tasks accurately and at high resolution.

  15. Recognizing patterns of visual field loss using unsupervised machine learning

    NASA Astrophysics Data System (ADS)

    Yousefi, Siamak; Goldbaum, Michael H.; Zangwill, Linda M.; Medeiros, Felipe A.; Bowd, Christopher

    2014-03-01

    Glaucoma is a potentially blinding optic neuropathy that results in a decrease in visual sensitivity. Visual field abnormalities (decreased visual sensitivity on psychophysical tests) are the primary means of glaucoma diagnosis. One form of visual field testing is Frequency Doubling Technology (FDT) that tests sensitivity at 52 points within the visual field. Like other psychophysical tests used in clinical practice, FDT results yield specific patterns of defect indicative of the disease. We used Gaussian Mixture Model with Expectation Maximization (GEM), (EM is used to estimate the model parameters) to automatically separate FDT data into clusters of normal and abnormal eyes. Principal component analysis (PCA) was used to decompose each cluster into different axes (patterns). FDT measurements were obtained from 1,190 eyes with normal FDT results and 786 eyes with abnormal (i.e., glaucomatous) FDT results, recruited from a university-based, longitudinal, multi-center, clinical study on glaucoma. The GEM input was the 52-point FDT threshold sensitivities for all eyes. The optimal GEM model separated the FDT fields into 3 clusters. Cluster 1 contained 94% normal fields (94% specificity) and clusters 2 and 3 combined, contained 77% abnormal fields (77% sensitivity). For clusters 1, 2 and 3 the optimal number of PCA-identified axes were 2, 2 and 5, respectively. GEM with PCA successfully separated FDT fields from healthy and glaucoma eyes and identified familiar glaucomatous patterns of loss.

  16. High-Performance Computing and Visualization | Energy Systems Integration

    Science.gov Websites

    Facility | NREL High-Performance Computing and Visualization High-Performance Computing and Visualization High-performance computing (HPC) and visualization at NREL propel technology innovation as a . Capabilities High-Performance Computing NREL is home to Peregrine-the largest high-performance computing system

  17. Abnormal intrinsic functional hubs in alcohol dependence: evidence from a voxelwise degree centrality analysis.

    PubMed

    Luo, Xiaoping; Guo, Linghong; Dai, Xi-Jian; Wang, Qinglai; Zhu, Wenzhong; Miao, Xinjun; Gong, Honghan

    2017-01-01

    To explore the abnormal intrinsic functional hubs in alcohol dependence using voxelwise degree centrality analysis approach, and their relationships with clinical features. Twenty-four male alcohol dependence subjects free of medicine (mean age, 50.21±9.62 years) and 24 age- and education-matched male healthy controls (mean age, 50.29±8.92 years) were recruited. The alcohol use disorders identification test and the severity of alcohol dependence questionnaire (SADQ) were administered to assess the severity of alcohol craving. Voxelwise degree centrality approach was used to assess the abnormal intrinsic functional hubs features in alcohol dependence. Simple linear regression analysis was performed to investigate the relationships between the clinical features and abnormal intrinsic functional hubs. Compared with healthy controls, alcohol dependence subjects exhibited significantly different degree centrality values in widespread left lateralization brain areas, including higher degree centrality values in the left precentral gyrus (BA 6), right hippocampus (BA 35, 36), and left orbitofrontal cortex (BA 11) and lower degree centrality values in the left cerebellum posterior lobe, bilateral secondary visual network (BA 18), and left precuneus (BA 7, 19). SADQ revealed a negative linear correlation with the degree centrality value in the left precentral gyrus ( R 2 =0.296, P =0.006). The specific abnormal intrinsic functional hubs appear to be disrupted by alcohol intoxication, which implicates at least three principal neural systems: including cerebellar, executive control, and visual cortex, which may further affect the normal motor behavior such as an explicit type of impaired driving behavior. These findings expand our understanding of the functional characteristics of alcohol dependence and may provide a new insight into the understanding of the dysfunction and pathophysiology of alcohol dependence.

  18. An annotation system for 3D fluid flow visualization

    NASA Technical Reports Server (NTRS)

    Loughlin, Maria M.; Hughes, John F.

    1995-01-01

    Annotation is a key activity of data analysis. However, current systems for data analysis focus almost exclusively on visualization. We propose a system which integrates annotations into a visualization system. Annotations are embedded in 3D data space, using the Post-it metaphor. This embedding allows contextual-based information storage and retrieval, and facilitates information sharing in collaborative environments. We provide a traditional database filter and a Magic Lens filter to create specialized views of the data. The system has been customized for fluid flow applications, with features which allow users to store parameters of visualization tools and sketch 3D volumes.

  19. The Real Culprit in Systemic Lupus Erythematosus: Abnormal Epigenetic Regulation

    PubMed Central

    Wu, Haijing; Zhao, Ming; Chang, Christopher; Lu, Qianjin

    2015-01-01

    Systemic lupus erythematosus (SLE) is an autoimmune disease involving multiple organs and the presence of anti-nuclear antibodies. The pathogenesis of SLE has been intensively studied but remains far from clear. B and T lymphocyte abnormalities, dysregulation of apoptosis, defects in the clearance of apoptotic materials, and various genetic and epigenetic factors are attributed to the development of SLE. The latest research findings point to the association between abnormal epigenetic regulation and SLE, which has attracted considerable interest worldwide. It is the purpose of this review to present and discuss the relationship between aberrant epigenetic regulation and SLE, including DNA methylation, histone modifications and microRNAs in patients with SLE, the possible mechanisms of immune dysfunction caused by epigenetic changes, and to better understand the roles of aberrant epigenetic regulation in the initiation and development of SLE and to provide an insight into the related therapeutic options in SLE. PMID:25988383

  20. Visual outcome after endoscopic third ventriculostomy for hydrocephalus.

    PubMed

    Jung, Ji-Ho; Chai, Yong-Hyun; Jung, Shin; Kim, In-Young; Jang, Woo-Youl; Moon, Kyung-Sub; Kim, Seul-Kee; Chong, Sangjoon; Kim, Seung-Ki; Jung, Tae-Young

    2018-02-01

    Hydrocephalus-related symptoms are mostly improved after successful endoscopic third ventriculostomy (ETV). However, visual symptoms can be different. This study was focused on visual symptoms. We analyzed the magnetic resonance images (MRI) of the orbit and visual outcomes. From August 2006 to November 2016, 50 patients with hydrocephalus underwent ETV. The male-to-female ratio was 33:17, and the median age was 61 years (range, 5-74 years). There were 18 pediatric and 32 adult patients. Abnormal orbital MRI findings included prominent subarachnoid space around the optic nerves and vertical tortuosity of the optic nerves. We retrospectively analyzed clinical symptoms, causes of hydrocephalus, ETV success score (ETVSS), ETV success rate, ETV complications, orbital MRI findings, and visual impairment score (VIS). The median duration of follow-up was 59 months (range, 3-113 months). The most common symptoms were headache, vomiting, and gait disturbance. Visual symptoms were found in 6 patients (12%). The most common causes of hydrocephalus were posterior fossa tumor in 13 patients, pineal tumor in 12, aqueductal stenosis in 8, thalamic malignant glioma in 7, and tectal glioma in 4. ETVSS was 70 in 3 patients, 80 in 34 patients, and 90 in 13 patients. ETV success rate was 80%. ETVSS 70 showed the trend in short-term survival compared to ETVSS 90 and 80. ETV complications included epidural hematoma requiring operation in one patient, transient hemiparesis in two patients, and infection in two patients. Preoperative abnormal orbital MRI findings were found in 18 patients and postoperative findings in 7 patients. Four of six patients with visual symptoms had abnormal MR findings. Three patients did not show VIS improvement, including two with severe visual symptoms. Patients with severe visual impairment were found to have bad outcomes. The visual symptoms related with increased intracranial pressure should be carefully monitored and controlled to improve outcomes.

  1. [Three-dimensional morphological modeling and visualization of wheat root system].

    PubMed

    Tan, Feng; Tang, Liang; Hu, Jun-Cheng; Jiang, Hai-Yan; Cao, Wei-Xing; Zhu, Yan

    2011-01-01

    Crop three-dimensional (3D) morphological modeling and visualization is an important part of digital plant study. This paper aimed to develop a 3D morphological model of wheat root system based on the parameters of wheat root morphological features, and to realize the visualization of wheat root growth. According to the framework of visualization technology for wheat root growth, a 3D visualization model of wheat root axis, including root axis growth model, branch geometric model, and root axis curve model, was developed firstly. Then, by integrating root topology, the corresponding pixel was determined, and the whole wheat root system was three-dimensionally re-constructed by using the morphological feature parameters in the root morphological model. Finally, based on the platform of OpenGL, and by integrating the technologies of texture mapping, lighting rendering, and collision detection, the 3D visualization of wheat root growth was realized. The 3D output of wheat root system from the model was vivid, which could realize the 3D root system visualization of different wheat cultivars under different water regimes and nitrogen application rates. This study could lay a technical foundation for further development of an integral visualization system of wheat plant.

  2. Visualization of system dynamics using phasegrams

    PubMed Central

    Herbst, Christian T.; Herzel, Hanspeter; Švec, Jan G.; Wyman, Megan T.; Fitch, W. Tecumseh

    2013-01-01

    A new tool for visualization and analysis of system dynamics is introduced: the phasegram. Its application is illustrated with both classical nonlinear systems (logistic map and Lorenz system) and with biological voice signals. Phasegrams combine the advantages of sliding-window analysis (such as the spectrogram) with well-established visualization techniques from the domain of nonlinear dynamics. In a phasegram, time is mapped onto the x-axis, and various vibratory regimes, such as periodic oscillation, subharmonics or chaos, are identified within the generated graph by the number and stability of horizontal lines. A phasegram can be interpreted as a bifurcation diagram in time. In contrast to other analysis techniques, it can be automatically constructed from time-series data alone: no additional system parameter needs to be known. Phasegrams show great potential for signal classification and can act as the quantitative basis for further analysis of oscillating systems in many scientific fields, such as physics (particularly acoustics), biology or medicine. PMID:23697715

  3. Visualizing Mobility of Public Transportation System.

    PubMed

    Zeng, Wei; Fu, Chi-Wing; Arisona, Stefan Müller; Erath, Alexander; Qu, Huamin

    2014-12-01

    Public transportation systems (PTSs) play an important role in modern cities, providing shared/massive transportation services that are essential for the general public. However, due to their increasing complexity, designing effective methods to visualize and explore PTS is highly challenging. Most existing techniques employ network visualization methods and focus on showing the network topology across stops while ignoring various mobility-related factors such as riding time, transfer time, waiting time, and round-the-clock patterns. This work aims to visualize and explore passenger mobility in a PTS with a family of analytical tasks based on inputs from transportation researchers. After exploring different design alternatives, we come up with an integrated solution with three visualization modules: isochrone map view for geographical information, isotime flow map view for effective temporal information comparison and manipulation, and OD-pair journey view for detailed visual analysis of mobility factors along routes between specific origin-destination pairs. The isotime flow map linearizes a flow map into a parallel isoline representation, maximizing the visualization of mobility information along the horizontal time axis while presenting clear and smooth pathways from origin to destinations. Moreover, we devise several interactive visual query methods for users to easily explore the dynamics of PTS mobility over space and time. Lastly, we also construct a PTS mobility model from millions of real passenger trajectories, and evaluate our visualization techniques with assorted case studies with the transportation researchers.

  4. Interaction Junk: User Interaction-Based Evaluation of Visual Analytic Systems

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Endert, Alexander; North, Chris

    2012-10-14

    With the growing need for visualization to aid users in understanding large, complex datasets, the ability for users to interact and explore these datasets is critical. As visual analytic systems have advanced to leverage powerful computational models and data analytics capabilities, the modes by which users engage and interact with the information are limited. Often, users are taxed with directly manipulating parameters of these models through traditional GUIs (e.g., using sliders to directly manipulate the value of a parameter). However, the purpose of user interaction in visual analytic systems is to enable visual data exploration – where users can focusmore » on their task, as opposed to the tool or system. As a result, users can engage freely in data exploration and decision-making, for the purpose of gaining insight. In this position paper, we discuss how evaluating visual analytic systems can be approached through user interaction analysis, where the goal is to minimize the cognitive translation between the visual metaphor and the mode of interaction (i.e., reducing the “Interactionjunk”). We motivate this concept through a discussion of traditional GUIs used in visual analytics for direct manipulation of model parameters, and the importance of designing interactions the support visual data exploration.« less

  5. A Space and Atmospheric Visualization Science System

    NASA Technical Reports Server (NTRS)

    Szuszczewicz, E. P.; Blanchard, P.; Mankofsky, A.; Goodrich, C.; Kamins, D.; Kulkarni, R.; Mcnabb, D.; Moroh, M.

    1994-01-01

    SAVS (a Space and Atmospheric Visualization Science system) is an integrated system with user-friendly functionality that employs a 'push-button' software environment that mimics the logical scientific processes in data acquisition, reduction, analysis, and visualization. All of this is accomplished without requiring a detailed understanding of the methods, networks, and modules that link the tools and effectively execute the functions. This report describes SAVS and its components, followed by several applications based on generic research interests in interplanetary and magnetospheric physics (IMP/ISTP), active experiments in space (CRRES), and mission planning focused on the earth's thermospheric, ionospheric, and mesospheric domains (TIMED). The final chapters provide a user-oriented description of interface functionalities, hands-on operations, and customized modules, with details of the primary modules presented in the appendices. The overall intent of the report is to reflect the accomplishments of the three-year development effort and to introduce potential users to the power and utility of the integrated data acquisition, analysis, and visualization system.

  6. Anatomy and physiology of the afferent visual system.

    PubMed

    Prasad, Sashank; Galetta, Steven L

    2011-01-01

    The efficient organization of the human afferent visual system meets enormous computational challenges. Once visual information is received by the eye, the signal is relayed by the retina, optic nerve, chiasm, tracts, lateral geniculate nucleus, and optic radiations to the striate cortex and extrastriate association cortices for final visual processing. At each stage, the functional organization of these circuits is derived from their anatomical and structural relationships. In the retina, photoreceptors convert photons of light to an electrochemical signal that is relayed to retinal ganglion cells. Ganglion cell axons course through the optic nerve, and their partial decussation in the chiasm brings together corresponding inputs from each eye. Some inputs follow pathways to mediate pupil light reflexes and circadian rhythms. However, the majority of inputs arrive at the lateral geniculate nucleus, which relays visual information via second-order neurons that course through the optic radiations to arrive in striate cortex. Feedback mechanisms from higher cortical areas shape the neuronal responses in early visual areas, supporting coherent visual perception. Detailed knowledge of the anatomy of the afferent visual system, in combination with skilled examination, allows precise localization of neuropathological processes and guides effective diagnosis and management of neuro-ophthalmic disorders. Copyright © 2011 Elsevier B.V. All rights reserved.

  7. Systems and Methods for Data Visualization Using Three-Dimensional Displays

    NASA Technical Reports Server (NTRS)

    Davidoff, Scott (Inventor); Djorgovski, Stanislav G. (Inventor); Estrada, Vicente (Inventor); Donalek, Ciro (Inventor)

    2017-01-01

    Data visualization systems and methods for generating 3D visualizations of a multidimensional data space are described. In one embodiment a 3D data visualization application directs a processing system to: load a set of multidimensional data points into a visualization table; create representations of a set of 3D objects corresponding to the set of data points; receive mappings of data dimensions to visualization attributes; determine the visualization attributes of the set of 3D objects based upon the selected mappings of data dimensions to 3D object attributes; update a visibility dimension in the visualization table for each of the plurality of 3D object to reflect the visibility of each 3D object based upon the selected mappings of data dimensions to visualization attributes; and interactively render 3D data visualizations of the 3D objects within the virtual space from viewpoints determined based upon received user input.

  8. Central nervous system abnormalities in Fanconi anaemia: patterns and frequency on magnetic resonance imaging

    PubMed Central

    Alston, Robert; Wright, Neville B; Chandler, Kate; Bonney, Denise; Wynn, Robert F; Will, Andrew M; Punekar, Maqsood; Loughran, Sean; Kilday, John-Paul; Schindler, Detlev; Patel, Leena; Meyer, Stefan

    2015-01-01

    Objective: Fanconi anaemia (FA) is an inherited disease associated with congenital and developmental abnormalities resulting from the disruption of a multigenic DNA damage response pathway. This study aimed to define the MRI appearances of the brain in patients with FA in correlation with their genetic and clinical features. Methods: A review of the brain MRI in 20 patients with FA was performed. Pituitary size and frequencies of the radiological findings of individuals with FA and age-matched controls were determined. Results: Abnormalities were identified in 18 (90%) patients with FA, the commonest being a small pituitary (68%, p < 0.01 females and p < 0.001 males). In five cases (25%, p = 0.02), the pituitary morphology was also abnormal. Posterior fossa abnormalities were seen in six cases (30%, p = 0.01) including Chiari I malformation (n = 3), Dandy–Walker variant (n = 2) and cerebellar atrophy (n = 2). Six patients (30%, p = 0.01) had morphological structural variation of the corpus callosum (CC). Conclusion: The incidence of central nervous system (CNS) abnormalities in FA is higher than previously reported, with a midline predominance that points to impact in the early stages of CNS development. MRI brain imaging is important for endocrine assessment and pre-transplant evaluation and can make an important contribution to clinical decision-making. Advances in knowledge: The incidence of brain structural abnormalities in FA is higher than previously reported, with abnormalities of the posterior fossa, CC and pituitary being common. There is an association with gender and reduction in pituitary size which does not strongly correlate with biochemically evident endocrine abnormality. PMID:26369989

  9. Online least squares one-class support vector machines-based abnormal visual event detection.

    PubMed

    Wang, Tian; Chen, Jie; Zhou, Yi; Snoussi, Hichem

    2013-12-12

    The abnormal event detection problem is an important subject in real-time video surveillance. In this paper, we propose a novel online one-class classification algorithm, online least squares one-class support vector machine (online LS-OC-SVM), combined with its sparsified version (sparse online LS-OC-SVM). LS-OC-SVM extracts a hyperplane as an optimal description of training objects in a regularized least squares sense. The online LS-OC-SVM learns a training set with a limited number of samples to provide a basic normal model, then updates the model through remaining data. In the sparse online scheme, the model complexity is controlled by the coherence criterion. The online LS-OC-SVM is adopted to handle the abnormal event detection problem. Each frame of the video is characterized by the covariance matrix descriptor encoding the moving information, then is classified into a normal or an abnormal frame. Experiments are conducted, on a two-dimensional synthetic distribution dataset and a benchmark video surveillance dataset, to demonstrate the promising results of the proposed online LS-OC-SVM method.

  10. Online Least Squares One-Class Support Vector Machines-Based Abnormal Visual Event Detection

    PubMed Central

    Wang, Tian; Chen, Jie; Zhou, Yi; Snoussi, Hichem

    2013-01-01

    The abnormal event detection problem is an important subject in real-time video surveillance. In this paper, we propose a novel online one-class classification algorithm, online least squares one-class support vector machine (online LS-OC-SVM), combined with its sparsified version (sparse online LS-OC-SVM). LS-OC-SVM extracts a hyperplane as an optimal description of training objects in a regularized least squares sense. The online LS-OC-SVM learns a training set with a limited number of samples to provide a basic normal model, then updates the model through remaining data. In the sparse online scheme, the model complexity is controlled by the coherence criterion. The online LS-OC-SVM is adopted to handle the abnormal event detection problem. Each frame of the video is characterized by the covariance matrix descriptor encoding the moving information, then is classified into a normal or an abnormal frame. Experiments are conducted, on a two-dimensional synthetic distribution dataset and a benchmark video surveillance dataset, to demonstrate the promising results of the proposed online LS-OC-SVM method. PMID:24351629

  11. Dependency visualization for complex system understanding

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Smart, J. Allison Cory

    1994-09-01

    With the volume of software in production use dramatically increasing, the importance of software maintenance has become strikingly apparent. Techniques now sought and developed for reverse engineering and design extraction and recovery. At present, numerous commercial products and research tools exist which are capable of visualizing a variety of programming languages and software constructs. The list of new tools and services continues to grow rapidly. Although the scope of the existing commercial and academic product set is quite broad, these tools still share a common underlying problem. The ability of each tool to visually organize object representations is increasingly impairedmore » as the number of components and component dependencies within systems increases. Regardless of how objects are defined, complex ``spaghetti`` networks result in nearly all large system cases. While this problem is immediately apparent in modem systems analysis involving large software implementations, it is not new. As will be discussed in Chapter 2, related problems involving the theory of graphs were identified long ago. This important theoretical foundation provides a useful vehicle for representing and analyzing complex system structures. While the utility of directed graph based concepts in software tool design has been demonstrated in literature, these tools still lack the capabilities necessary for large system comprehension. This foundation must therefore be expanded with new organizational and visualization constructs necessary to meet this challenge. This dissertation addresses this need by constructing a conceptual model and a set of methods for interactively exploring, organizing, and understanding the structure of complex software systems.« less

  12. The effects of chlorpromazine and lorazepam on abnormal antisaccade and no-saccade distractibility.

    PubMed

    Green, J F; King, D J

    1998-10-15

    Abnormally high levels of saccadic distractibility have been demonstrated to occur in patients with schizophrenia. Converging evidence implicates frontal cortical dysfunction as a mechanism; however, much of the neuropharmacology of saccadic distractibility has not yet been established. We measured antisaccade, no-saccade, and visually guided saccade components in healthy subjects following single doses of lorazepam 2 mg, chlorpromazine 50-100 mg, and placebo. Visual analogue rating scales (VARS) provided a subjective measure of sedation. Lorazepam, but not chlorpromazine, was shown to cause an increase in saccadic distractibility in both the antisaccade and no-saccade tasks. Peak visually guided saccade velocity was decreased by lorazepam and chlorpromazine in a dose-dependent manner, with corresponding changes seen in VARS. Lorazepam, unexpectedly, did not affect peak antisaccade velocity. The background level of antisaccade directional errors was 6.43%, which is relatively low compared to control groups in patient studies. These results support the view that abnormal saccadic distractibility in patients with schizophrenia is not due to an acute effect of antipsychotic medication. The use of benzodiazepines and the level of task practice are highlighted as possible confounding variables in patient studies. The implications of these results for the current neuropathological theories of abnormal saccadic distractibility are discussed.

  13. Visual attention shifting in autism spectrum disorders.

    PubMed

    Richard, Annette E; Lajiness-O'Neill, Renee

    2015-01-01

    Abnormal visual attention has been frequently observed in autism spectrum disorders (ASD). Abnormal shifting of visual attention is related to abnormal development of social cognition and has been identified as a key neuropsychological finding in ASD. Better characterizing attention shifting in ASD and its relationship with social functioning may help to identify new targets for intervention and improving social communication in these disorders. Thus, the current study investigated deficits in attention shifting in ASD as well as relationships between attention shifting and social communication in ASD and neurotypicals (NT). To investigate deficits in visual attention shifting in ASD, 20 ASD and 20 age- and gender-matched NT completed visual search (VS) and Navon tasks with attention-shifting demands as well as a set-shifting task. VS was a feature search task with targets defined in one of two dimensions; Navon required identification of a target letter presented at the global or local level. Psychomotor and processing speed were entered as covariates. Relationships between visual attention shifting, set shifting, and social functioning were also examined. ASD and NT showed comparable costs of shifting attention. However, psychomotor and processing speed were slower in ASD than in NT, and psychomotor and processing speed were positively correlated with attention-shifting costs on Navon and VS, respectively, for both groups. Attention shifting on VS and Navon were correlated among NT, while attention shifting on Navon was correlated with set shifting among ASD. Attention-shifting costs on Navon were positively correlated with restricted and repetitive behaviors among ASD. Relationships between attention shifting and psychomotor and processing speed, as well as relationships between measures of different aspects of visual attention shifting, suggest inefficient top-down influences over preattentive visual processing in ASD. Inefficient attention shifting may be

  14. Immunostaining to visualize murine enteric nervous system development.

    PubMed

    Barlow-Anacker, Amanda J; Erickson, Christopher S; Epstein, Miles L; Gosain, Ankush

    2015-04-29

    The enteric nervous system is formed by neural crest cells that proliferate, migrate and colonize the gut. Following colonization, neural crest cells must then differentiate into neurons with markers specific for their neurotransmitter phenotype. Cholinergic neurons, a major neurotransmitter phenotype in the enteric nervous system, are identified by staining for choline acetyltransferase (ChAT), the synthesizing enzyme for acetylcholine. Historical efforts to visualize cholinergic neurons have been hampered by antibodies with differing specificities to central nervous system versus peripheral nervous system ChAT. We and others have overcome this limitation by using an antibody against placental ChAT, which recognizes both central and peripheral ChAT, to successfully visualize embryonic enteric cholinergic neurons. Additionally, we have compared this antibody to genetic reporters for ChAT and shown that the antibody is more reliable during embryogenesis. This protocol describes a technique for dissecting, fixing and immunostaining of the murine embryonic gastrointestinal tract to visualize enteric nervous system neurotransmitter expression.

  15. Natural History of the Central Structural Abnormalities in Choroideremia: A Prospective Cross-Sectional Study.

    PubMed

    Aleman, Tomas S; Han, Grace; Serrano, Leona W; Fuerst, Nicole M; Charlson, Emily S; Pearson, Denise J; Chung, Daniel C; Traband, Anastasia; Pan, Wei; Ying, Gui-Shuang; Bennett, Jean; Maguire, Albert M; Morgan, Jessica I W

    2017-03-01

    To describe in detail the central retinal structure of a large group of patients with choroideremia (CHM). A prospective, cross-sectional, descriptive study. Patients (n = 97, age 6-71 years) with CHM and subjects with normal vision (n = 44; ages 10-50 years) were included. Subjects were examined with spectral-domain optical coherence tomography (SD OCT) and near-infrared reflectance imaging. Visual acuity (VA) was measured during their encounter or obtained from recent ophthalmic examinations. Visual thresholds were measured in a subset of patients (n = 24) with automated static perimetry within the central regions (±15°) examined with SD OCT. Visual acuity and visual thresholds; total nuclear layer, inner nuclear layer (INL), and outer nuclear layer (ONL) thicknesses; and horizontal extent of the ONL and the photoreceptor outer segment (POS) interdigitation zone (IZ). Earliest abnormalities in regions with normally appearing retinal pigment epithelium (RPE) were the loss of the POS and ellipsoid zone associated with rod dysfunction. Transition zones (TZs) from relatively preserved retina to severe ONL thinning and inner retinal thickening moved centripetally with age. Most patients (88%) retained VAs better than 20/40 until their fifth decade of life. The VA decline coincided with migration of the TZ near the foveal center. There were outer retinal tubulations in degenerated, nonatrophic retina in the majority (69%) of patients. In general, RPE abnormalities paralleled photoreceptor degeneration, although there were regions with detectable but abnormally thin ONL co-localizing with severe RPE depigmentation and choroidal thinning. Abnormalities of the POS and rod dysfunction are the earliest central abnormalities observed in CHM. Foveal function is relatively preserved until the fifth decade of life. Migration of the TZs to the foveal center with foveal thinning and structural disorganization heralded central VA loss. The relationships established may help

  16. Visual management support system

    Treesearch

    Lee Anderson; Jerry Mosier; Geoffrey Chandler

    1979-01-01

    The Visual Management Support System (VMSS) is an extension of an existing computer program called VIEWIT, which has been extensively used by the U. S. Forest Service. The capabilities of this program lie in the rapid manipulation of large amounts of data, specifically opera-ting as a tool to overlay or merge one set of data with another. VMSS was conceived to...

  17. A Unified Air-Sea Visualization System: Survey on Gridding Structures

    NASA Technical Reports Server (NTRS)

    Anand, Harsh; Moorhead, Robert

    1995-01-01

    The goal is to develop a Unified Air-Sea Visualization System (UASVS) to enable the rapid fusion of observational, archival, and model data for verification and analysis. To design and develop UASVS, modelers were polled to determine the gridding structures and visualization systems used, and their needs with respect to visual analysis. A basic UASVS requirement is to allow a modeler to explore multiple data sets within a single environment, or to interpolate multiple datasets onto one unified grid. From this survey, the UASVS should be able to visualize 3D scalar/vector fields; render isosurfaces; visualize arbitrary slices of the 3D data; visualize data defined on spectral element grids with the minimum number of interpolation stages; render contours; produce 3D vector plots and streamlines; provide unified visualization of satellite images, observations and model output overlays; display the visualization on a projection of the users choice; implement functions so the user can derive diagnostic values; animate the data to see the time-evolution; animate ocean and atmosphere at different rates; store the record of cursor movement, smooth the path, and animate a window around the moving path; repeatedly start and stop the visual time-stepping; generate VHS tape animations; work on a variety of workstations; and allow visualization across clusters of workstations and scalable high performance computer systems.

  18. VisualEyes: a modular software system for oculomotor experimentation.

    PubMed

    Guo, Yi; Kim, Eun H; Kim, Eun; Alvarez, Tara; Alvarez, Tara L

    2011-03-25

    Eye movement studies have provided a strong foundation forming an understanding of how the brain acquires visual information in both the normal and dysfunctional brain.(1) However, development of a platform to stimulate and store eye movements can require substantial programming, time and costs. Many systems do not offer the flexibility to program numerous stimuli for a variety of experimental needs. However, the VisualEyes System has a flexible architecture, allowing the operator to choose any background and foreground stimulus, program one or two screens for tandem or opposing eye movements and stimulate the left and right eye independently. This system can significantly reduce the programming development time needed to conduct an oculomotor study. The VisualEyes System will be discussed in three parts: 1) the oculomotor recording device to acquire eye movement responses, 2) the VisualEyes software written in LabView, to generate an array of stimuli and store responses as text files and 3) offline data analysis. Eye movements can be recorded by several types of instrumentation such as: a limbus tracking system, a sclera search coil, or a video image system. Typical eye movement stimuli such as saccadic steps, vergent ramps and vergent steps with the corresponding responses will be shown. In this video report, we demonstrate the flexibility of a system to create numerous visual stimuli and record eye movements that can be utilized by basic scientists and clinicians to study healthy as well as clinical populations.

  19. The right cerebral hemisphere: emotion, music, visual-spatial skills, body-image, dreams, and awareness.

    PubMed

    Joseph, R

    1988-09-01

    Based on a review of numerous studies conducted on normal, neurosurgical and brain-injured individuals, the right cerebral hemisphere appears to be dominant in the perception and identification of environmental and nonverbal sounds; the analysis of geometric and visual space (e.g., depth perception, visual closure); somesthesis, stereognosis, the maintenance of the body image; the production of dreams during REM sleep; the perception of most aspects of musical stimuli; and the comprehension and expression of prosodic, melodic, visual, facial, and verbal emotion. When the right hemisphere is damaged a variety of cognitive abnormalities may result, including hemi-inattention and neglect, prosopagnosia, constructional apraxia, visual-perceptual disturbances, and agnosia for environmental, musical, and emotional sounds. Similarly, a myriad of affective abnormalities may occur, including indifference, depression, hysteria, gross social-emotional disinhibition, florid manic excitement, childishness, euphoria, impulsivity, and abnormal sexual behavior. Patients may become delusional, engage in the production of bizzare confabulations and experience a host of somatic disturbances such as pain and body-perceptual distortions. Based on studies of normal and "split-brain" functioning, it also appears that the right hemisphere maintains a highly developed social-emotional mental system and can independently perceive, recall and act on certain memories and experiences without the aid or active reflective participation of the left. This leads to situations in which the right and left halves of the brain sometime act in an uncooperative fashion, which gives rise to inter-manual and intra-psychic conflicts.

  20. Visualization and Analytics Software Tools for Peregrine System |

    Science.gov Websites

    R is a language and environment for statistical computing and graphics. Go to the R web site for System Visualization and Analytics Software Tools for Peregrine System Learn about the available visualization for OpenGL-based applications. For more information, please go to the FastX page. ParaView An open

  1. Immune Abnormalities in Patients with Autism.

    ERIC Educational Resources Information Center

    Warren, Reed P.; And Others

    1986-01-01

    A study of 31 autistic patients (3-28 years old) has revealed several immune-system abnormalities, including decreased numbers of T lymphocytes and an altered ratio of helper-to-suppressor T cells. Immune-system abnormalities may be directly related to underlying biologic processes of autism or an indirect reflection of the actual pathologic…

  2. Abnormal GABAergic function and face processing in schizophrenia: A pharmacologic-fMRI study.

    PubMed

    Tso, Ivy F; Fang, Yu; Phan, K Luan; Welsh, Robert C; Taylor, Stephan F

    2015-10-01

    The involvement of the gamma-aminobutyric acid (GABA) system in schizophrenia is suggested by postmortem studies and the common use of GABA receptor-potentiating agents in treatment. In a recent study, we used a benzodiazepine challenge to demonstrate abnormal GABAergic function during processing of negative visual stimuli in schizophrenia. This study extended this investigation by mapping GABAergic mechanisms associated with face processing and social appraisal in schizophrenia using a benzodiazepine challenge. Fourteen stable, medicated schizophrenia/schizoaffective patients (SZ) and 13 healthy controls (HC) underwent functional MRI using the blood oxygenation level-dependent (BOLD) technique while they performed the Socio-emotional Preference Task (SePT) on emotional face stimuli ("Do you like this face?"). Participants received single-blinded intravenous saline and lorazepam (LRZ) in two separate sessions separated by 1-3weeks. Both SZ and HC recruited medial prefrontal cortex/anterior cingulate during the SePT, relative to gender identification. A significant drug by group interaction was observed in the medial occipital cortex, such that SZ showed increased BOLD signal to LRZ challenge, while HC showed an expected decrease of signal; the interaction did not vary by task. The altered BOLD response to LRZ challenge in SZ was significantly correlated with increased negative affect across multiple measures. The altered response to LRZ challenge suggests that abnormal face processing and negative affect in SZ are associated with altered GABAergic function in the visual cortex, underscoring the role of impaired visual processing in socio-emotional deficits in schizophrenia. Copyright © 2015 Elsevier B.V. All rights reserved.

  3. Joint ultrasound baseline abnormalities predict a specific long-term clinical outcome in systemic lupus erythematosus patients.

    PubMed

    Corzo, P; Salman-Monte, T C; Torrente-Segarra, V; Polino, L; Mojal, S; Carbonell-Abelló, J

    2017-06-01

    Objective To describe long-term clinical and serological outcome in all systemic lupus erythematosus (SLE) domains in SLE patients with hand arthralgia (HA) and joint ultrasound (JUS) inflammatory abnormalities, and to compare them with asymptomatic SLE patients with normal JUS. Methods SLE patients with HA who presented JUS inflammatory abnormalities ('cases') and SLE patients without HA who did not exhibit JUS abnormalities at baseline ('controls') were included. All SLE clinical and serological domain involvement data were collected. End follow-up clinical activity and damage scores (systemic lupus erythematosus disease activity index (SLEDAI), Systemic Lupus International Collaborating Clinics/American College of Rheumatology (SLICC/ACR)) were recorded. JUS inflammatory abnormalities were defined based on the Proceedings of the Seventh International Consensus Conference on Outcome Measures in Rheumatology Clinical Trials (OMERACT-7) definitions. Statistical analyses were carried out to compare 'cases' and 'controls'. Results A total of 35 patients were recruited. The 'cases', n = 18/35, had a higher incidence of musculoskeletal involvement (arthralgia and/or arthritis) through the follow-up period (38.9% vs 0%, p = 0.008) and received more hydroxychloroquine (61.1% vs 25.0%, p = 0.034) and methotrexate (27.8% vs 0%, p = 0.046) compared to 'controls', n = 17/35. Other comparisons did not reveal any statistical differences. Conclusions We found SLE patients with arthralgia who presented JUS inflammatory abnormalities received more hydroxychloroquine and methotrexate, mainly due to persistent musculoskeletal involvement over time. JUS appears to be a useful technique for predicting worse musculoskeletal outcome in SLE patients.

  4. Visualizing Terrestrial and Aquatic Systems in 3-D

    EPA Science Inventory

    The environmental modeling community has a long-standing need for affordable, easy-to-use tools that support 3-D visualization of complex spatial and temporal model output. The Visualization of Terrestrial and Aquatic Systems project (VISTAS) aims to help scientists produce effe...

  5. Satellite Imagery Assisted Road-Based Visual Navigation System

    NASA Astrophysics Data System (ADS)

    Volkova, A.; Gibbens, P. W.

    2016-06-01

    There is a growing demand for unmanned aerial systems as autonomous surveillance, exploration and remote sensing solutions. Among the key concerns for robust operation of these systems is the need to reliably navigate the environment without reliance on global navigation satellite system (GNSS). This is of particular concern in Defence circles, but is also a major safety issue for commercial operations. In these circumstances, the aircraft needs to navigate relying only on information from on-board passive sensors such as digital cameras. An autonomous feature-based visual system presented in this work offers a novel integral approach to the modelling and registration of visual features that responds to the specific needs of the navigation system. It detects visual features from Google Earth* build a feature database. The same algorithm then detects features in an on-board cameras video stream. On one level this serves to localise the vehicle relative to the environment using Simultaneous Localisation and Mapping (SLAM). On a second level it correlates them with the database to localise the vehicle with respect to the inertial frame. The performance of the presented visual navigation system was compared using the satellite imagery from different years. Based on comparison results, an analysis of the effects of seasonal, structural and qualitative changes of the imagery source on the performance of the navigation algorithm is presented. * The algorithm is independent of the source of satellite imagery and another provider can be used

  6. Long-term visual outcomes in extremely low-birth-weight children (an American Ophthalmological Society thesis).

    PubMed

    Spencer, Rand

    2006-01-01

    The goal is to analyze the long-term visual outcome of extremely low-birth-weight children. This is a retrospective analysis of eyes of extremely low-birth-weight children on whom vision testing was performed. Visual outcomes were studied by analyzing acuity outcomes at >/=36 months of adjusted age, correlating early acuity testing with final visual outcome and evaluating adverse risk factors for vision. Data from 278 eyes are included. Mean birth weight was 731g, and mean gestational age at birth was 26 weeks. 248 eyes had grating acuity outcomes measured at 73 +/- 36 months, and 183 eyes had recognition acuity testing at 76 +/- 39 months. 54% had below normal grating acuities, and 66% had below normal recognition acuities. 27% of grating outcomes and 17% of recognition outcomes were Abnormal early grating acuity testing was predictive of abnormal grating (P < .0001) and recognition (P = .0001) acuity testing at >/=3 years of age. A slower-than-normal rate of early visual development was predictive of abnormal grating acuity (P < .0001) and abnormal recognition acuity (P < .0001) at >/=3 years of age. Eyes diagnosed with maximal retinopathy of prematurity in zone I had lower acuity outcomes (P = .0002) than did those with maximal retinopathy of prematurity in zone II/III. Eyes of children born at abnormal recognition acuity than did those of children born at >28 weeks gestational age. Eyes of children with poorer general health after premature birth had a 5.3 times greater risk of abnormal recognition acuity. Long-term visual development in extremely low-birth-weight infants is problematic and associated with a high risk of subnormal acuity. Early acuity testing is useful in identifying children at greatest risk for long-term visual abnormalities. Gestational age at birth of abnormal long-term outcome.

  7. LONG-TERM VISUAL OUTCOMES IN EXTREMELY LOW-BIRTH-WEIGHT CHILDREN (AN AMERICAN OPHTHALMOLOGICAL SOCIETY THESIS)

    PubMed Central

    Spencer, Rand

    2006-01-01

    Purpose The goal is to analyze the long-term visual outcome of extremely low-birth-weight children. Methods This is a retrospective analysis of eyes of extremely low-birth-weight children on whom vision testing was performed. Visual outcomes were studied by analyzing acuity outcomes at ≥36 months of adjusted age, correlating early acuity testing with final visual outcome and evaluating adverse risk factors for vision. Results Data from 278 eyes are included. Mean birth weight was 731g, and mean gestational age at birth was 26 weeks. 248 eyes had grating acuity outcomes measured at 73 ± 36 months, and 183 eyes had recognition acuity testing at 76 ± 39 months. 54% had below normal grating acuities, and 66% had below normal recognition acuities. 27% of grating outcomes and 17% of recognition outcomes were ≤20/200. Abnormal early grating acuity testing was predictive of abnormal grating (P < .0001) and recognition (P = .0001) acuity testing at ≥3 years of age. A slower-than-normal rate of early visual development was predictive of abnormal grating acuity (P < .0001) and abnormal recognition acuity (P < .0001) at ≥3 years of age. Eyes diagnosed with maximal retinopathy of prematurity in zone I had lower acuity outcomes (P = .0002) than did those with maximal retinopathy of prematurity in zone II/III. Eyes of children born at ≤28 weeks gestational age had 4.1 times greater risk for abnormal recognition acuity than did those of children born at >28 weeks gestational age. Eyes of children with poorer general health after premature birth had a 5.3 times greater risk of abnormal recognition acuity. Conclusions Long-term visual development in extremely low-birth-weight infants is problematic and associated with a high risk of subnormal acuity. Early acuity testing is useful in identifying children at greatest risk for long-term visual abnormalities. Gestational age at birth of ≤ 28 weeks was associated with a higher risk of an abnormal long-term outcome. PMID

  8. Coronary artery abnormalities in children with systemic-onset juvenile idiopathic arthritis.

    PubMed

    Lefèvre-Utile, Alain; Galeotti, Caroline; Koné-Paut, Isabelle

    2014-05-01

    Still's disease (Systemic-onset Juvenile Idiopathic Arthritis: SoJIA) is characterised by high-spiking daily fevers, arthritis and evanescent rashes. Diagnosis of Still's disease is often challenging. Infectious diseases and other inflammatory conditions, especially in young children, Kawasaki disease may look similar. Clinicians often rely on echocardiographic evidence of coronary artery abnormalities to differentiate between Kawasaki disease and Still's disease. Coronary artery dilation would typically favour the diagnosis of Kawasaki disease. We present four children with Still's disease and coronary artery abnormalities who were initially misdiagnosed as Kawasaki disease. The first patient had pericarditis and an irregular wall of the left coronary artery, without dilation on echocardiography. The second patient had a left coronary artery dilatation and a pericarditis. The third patient had thickened left coronary artery walls, and the fourth patient had a hyperechogenicity of the left and right coronary arteries. They received IVIG without success. The diagnosis of Still's disease was made secondary with evidence of persistent arthritis. All but one patient finally needed biologic treatments. Coronary abnormalities may be observed during various febrile conditions and do not exclude the diagnosis of Still's disease. Copyright © 2013 Société française de rhumatologie. Published by Elsevier SAS. All rights reserved.

  9. Asymmetrical Interhemispheric Connections Develop in Cat Visual Cortex after Early Unilateral Convergent Strabismus: Anatomy, Physiology, and Mechanisms

    PubMed Central

    Bui Quoc, Emmanuel; Ribot, Jérôme; Quenech’Du, Nicole; Doutremer, Suzette; Lebas, Nicolas; Grantyn, Alexej; Aushana, Yonane; Milleret, Chantal

    2011-01-01

    In the mammalian primary visual cortex, the corpus callosum contributes to the unification of the visual hemifields that project to the two hemispheres. Its development depends on visual experience. When this is abnormal, callosal connections must undergo dramatic anatomical and physiological changes. However, data concerning these changes are sparse and incomplete. Thus, little is known about the impact of abnormal postnatal visual experience on the development of callosal connections and their role in unifying representation of the two hemifields. Here, the effects of early unilateral convergent strabismus (a model of abnormal visual experience) were fully characterized with respect to the development of the callosal connections in cat visual cortex, an experimental model for humans. Electrophysiological responses and 3D reconstruction of single callosal axons show that abnormally asymmetrical callosal connections develop after unilateral convergent strabismus, resulting from an extension of axonal branches of specific orders in the hemisphere ipsilateral to the deviated eye and a decreased number of nodes and terminals in the other (ipsilateral to the non-deviated eye). Furthermore this asymmetrical organization prevents the establishment of a unifying representation of the two visual hemifields. As a general rule, we suggest that crossed and uncrossed retino-geniculo-cortical pathways contribute successively to the development of the callosal maps in visual cortex. PMID:22275883

  10. Abnormal pressure in hydrocarbon environments

    USGS Publications Warehouse

    Law, B.E.; Spencer, C.W.

    1998-01-01

    Abnormal pressures, pressures above or below hydrostatic pressures, occur on all continents in a wide range of geological conditions. According to a survey of published literature on abnormal pressures, compaction disequilibrium and hydrocarbon generation are the two most commonly cited causes of abnormally high pressure in petroleum provinces. In young (Tertiary) deltaic sequences, compaction disequilibrium is the dominant cause of abnormal pressure. In older (pre-Tertiary) lithified rocks, hydrocarbon generation, aquathermal expansion, and tectonics are most often cited as the causes of abnormal pressure. The association of abnormal pressures with hydrocarbon accumulations is statistically significant. Within abnormally pressured reservoirs, empirical evidence indicates that the bulk of economically recoverable oil and gas occurs in reservoirs with pressure gradients less than 0.75 psi/ft (17.4 kPa/m) and there is very little production potential from reservoirs that exceed 0.85 psi/ft (19.6 kPa/m). Abnormally pressured rocks are also commonly associated with unconventional gas accumulations where the pressuring phase is gas of either a thermal or microbial origin. In underpressured, thermally mature rocks, the affected reservoirs have most often experienced a significant cooling history and probably evolved from an originally overpressured system.

  11. Detection of Structural Abnormalities Using Neural Nets

    NASA Technical Reports Server (NTRS)

    Zak, M.; Maccalla, A.; Daggumati, V.; Gulati, S.; Toomarian, N.

    1996-01-01

    This paper describes a feed-forward neural net approach for detection of abnormal system behavior based upon sensor data analyses. A new dynamical invariant representing structural parameters of the system is introduced in such a way that any structural abnormalities in the system behavior are detected from the corresponding changes to the invariant.

  12. Technical note: real-time web-based wireless visual guidance system for radiotherapy.

    PubMed

    Lee, Danny; Kim, Siyong; Palta, Jatinder R; Kim, Taeho

    2017-06-01

    Describe a Web-based wireless visual guidance system that mitigates issues associated with hard-wired audio-visual aided patient interactive motion management systems that are cumbersome to use in routine clinical practice. Web-based wireless visual display duplicates an existing visual display of a respiratory-motion management system for visual guidance. The visual display of the existing system is sent to legacy Web clients over a private wireless network, thereby allowing a wireless setting for real-time visual guidance. In this study, active breathing coordinator (ABC) trace was used as an input for visual display, which captured and transmitted to Web clients. Virtual reality goggles require two (left and right eye view) images for visual display. We investigated the performance of Web-based wireless visual guidance by quantifying (1) the network latency of visual displays between an ABC computer display and Web clients of a laptop, an iPad mini 2 and an iPhone 6, and (2) the frame rate of visual display on the Web clients in frames per second (fps). The network latency of visual display between the ABC computer and Web clients was about 100 ms and the frame rate was 14.0 fps (laptop), 9.2 fps (iPad mini 2) and 11.2 fps (iPhone 6). In addition, visual display for virtual reality goggles was successfully shown on the iPhone 6 with 100 ms and 11.2 fps. A high network security was maintained by utilizing the private network configuration. This study demonstrated that a Web-based wireless visual guidance can be a promising technique for clinical motion management systems, which require real-time visual display of their outputs. Based on the results of this study, our approach has the potential to reduce clutter associated with wired-systems, reduce space requirements, and extend the use of medical devices from static usage to interactive and dynamic usage in a radiotherapy treatment vault.

  13. Robot Command Interface Using an Audio-Visual Speech Recognition System

    NASA Astrophysics Data System (ADS)

    Ceballos, Alexánder; Gómez, Juan; Prieto, Flavio; Redarce, Tanneguy

    In recent years audio-visual speech recognition has emerged as an active field of research thanks to advances in pattern recognition, signal processing and machine vision. Its ultimate goal is to allow human-computer communication using voice, taking into account the visual information contained in the audio-visual speech signal. This document presents a command's automatic recognition system using audio-visual information. The system is expected to control the laparoscopic robot da Vinci. The audio signal is treated using the Mel Frequency Cepstral Coefficients parametrization method. Besides, features based on the points that define the mouth's outer contour according to the MPEG-4 standard are used in order to extract the visual speech information.

  14. Infant Face Preferences after Binocular Visual Deprivation

    ERIC Educational Resources Information Center

    Mondloch, Catherine J.; Lewis, Terri L.; Levin, Alex V.; Maurer, Daphne

    2013-01-01

    Early visual deprivation impairs some, but not all, aspects of face perception. We investigated the possible developmental roots of later abnormalities by using a face detection task to test infants treated for bilateral congenital cataract within 1 hour of their first focused visual input. The seven patients were between 5 and 12 weeks old…

  15. Strabismus and the Oculomotor System: Insights from Macaque Models

    PubMed Central

    Das, Vallabh E.

    2017-01-01

    Disrupting binocular vision in infancy leads to strabismus and oftentimes to a variety of associated visual sensory deficits and oculomotor abnormalities. Investigation of this disorder has been aided by the development of various animal models, each of which has advantages and disadvantages. In comparison to studies of binocular visual responses in cortical structures, investigations of neural oculomotor structures that mediate the misalignment and abnormalities of eye movements have been more recent, and these studies have shown that different brain areas are intimately involved in driving several aspects of the strabismic condition, including horizontal misalignment, dissociated deviations, A and V patterns of strabismus, disconjugate eye movements, nystagmus, and fixation switch. The responses of cells in visual and oculomotor areas that potentially drive the sensory deficits and also eye alignment and eye movement abnormalities follow a general theme of disrupted calibration, lower sensitivity, and poorer specificity compared with the normally developed visual oculomotor system. PMID:28532347

  16. Conceptual design study for a teleoperator visual system, phase 2

    NASA Technical Reports Server (NTRS)

    Grant, C.; Meirick, R.; Polhemus, C.; Spencer, R.; Swain, D.; Twell, R.

    1973-01-01

    An analysis of the concept for the hybrid stereo-monoscopic television visual system is reported. The visual concept is described along with the following subsystems: illumination, deployment/articulation, telecommunications, visual displays, and the controls and display station.

  17. Relationship Between Clinical and Immunological Features with Magnetic Resonance Imaging Abnormalities in Female Patients with Neuropsychiatric Systemic Lupus Erythematosus

    PubMed Central

    Wang, Hai-Peng; Wang, Cui-Yan; Pan, Zheng-Lun; Zhao, Jun-Yu; Zhao, Bin

    2016-01-01

    Background: Conventional magnetic resonance imaging (MRI) is the preferred neuroimaging method in the evaluation of neuropsychiatric systemic lupus erythematosus (NPSLE). The purpose of this study was to investigate the association between clinical and immunological features with MRI abnormalities in female patients with NPSLE, to screen for the value of conventional MRI in NPSLE. Methods: A total of 59 female NPSLE patients with conventional MRI examinations were enrolled in this retrospective study. All patients were classified into different groups according to MRI abnormalities. Both clinical and immunological features were compared between MRI abnormal and normal groups. One-way analysis of variance was used to compare the systemic lupus erythematosus disease activity index (SLEDAI) score for MRI abnormalities. Multivariate logistic regression analysis investigated the correlation between immunological features, neuropsychiatric manifestations, and MRI abnormalities. Results: Thirty-six NPSLE patients (61%) showed a variety of MRI abnormalities. There were statistically significant differences in SLEDAI scores (P < 0.001), incidence of neurologic disorders (P = 0.001), levels of 24-h proteinuria (P = 0.001) and immunoglobulin M (P = 0.004), and incidence of acute confusional state (P = 0.002), cerebrovascular disease (P = 0.004), and seizure disorder (P = 0.028) between MRI abnormal and normal groups. In the MRI abnormal group, SLEDAI scores for cerebral atrophy (CA), cortex involvement, and restricted diffusion (RD) were much higher than in the MRI normal group (P < 0.001, P = 0.002, P = 0.038, respectively). Statistically significant positive correlations between seizure disorder and cortex involvement (odds ratio [OR] = 14.90; 95% confidence interval [CI], 1.50–151.70; P = 0.023) and cerebrovascular disease and infratentorial involvement (OR = 10.00; 95% CI, 1.70–60.00; P = 0.012) were found. Conclusions: MRI abnormalities in NPSLE, especially CA

  18. A visualization system for CT based pulmonary fissure analysis

    NASA Astrophysics Data System (ADS)

    Pu, Jiantao; Zheng, Bin; Park, Sang Cheol

    2009-02-01

    In this study we describe a visualization system of pulmonary fissures depicted on CT images. The purpose is to provide clinicians with an intuitive perception of a patient's lung anatomy through an interactive examination of fissures, enhancing their understanding and accurate diagnosis of lung diseases. This system consists of four key components: (1) region-of-interest segmentation; (2) three-dimensional surface modeling; (3) fissure type classification; and (4) an interactive user interface, by which the extracted fissures are displayed flexibly in different space domains including image space, geometric space, and mixed space using simple toggling "on" and "off" operations. In this system, the different visualization modes allow users not only to examine the fissures themselves but also to analyze the relationship between fissures and their surrounding structures. In addition, the users can adjust thresholds interactively to visualize the fissure surface under different scanning and processing conditions. Such a visualization tool is expected to facilitate investigation of structures near the fissures and provide an efficient "visual aid" for other applications such as treatment planning and assessment of therapeutic efficacy as well as education of medical professionals.

  19. A habituation based approach for detection of visual changes in surveillance camera

    NASA Astrophysics Data System (ADS)

    Sha'abani, M. N. A. H.; Adan, N. F.; Sabani, M. S. M.; Abdullah, F.; Nadira, J. H. S.; Yasin, M. S. M.

    2017-09-01

    This paper investigates a habituation based approach in detecting visual changes using video surveillance systems in a passive environment. Various techniques have been introduced for dynamic environment such as motion detection, object classification and behaviour analysis. However, in a passive environment, most of the scenes recorded by the surveillance system are normal. Therefore, implementing a complex analysis all the time in the passive environment resulting on computationally expensive, especially when using a high video resolution. Thus, a mechanism of attention is required, where the system only responds to an abnormal event. This paper proposed a novelty detection mechanism in detecting visual changes and a habituation based approach to measure the level of novelty. The objective of the paper is to investigate the feasibility of the habituation based approach in detecting visual changes. Experiment results show that the approach are able to accurately detect the presence of novelty as deviations from the learned knowledge.

  20. A novel visual pipework inspection system

    NASA Astrophysics Data System (ADS)

    Summan, Rahul; Jackson, William; Dobie, Gordon; MacLeod, Charles; Mineo, Carmelo; West, Graeme; Offin, Douglas; Bolton, Gary; Marshall, Stephen; Lille, Alexandre

    2018-04-01

    The interior visual inspection of pipelines in the nuclear industry is a safety critical activity conducted during outages to ensure the continued safe and reliable operation of plant. Typically, the video output by a manually deployed probe is viewed by an operator looking to identify and localize surface defects such as corrosion, erosion and pitting. However, it is very challenging to estimate the nature and extent of defects by viewing a large structure through a relatively small field of view. This work describes a new visual inspection system employing photogrammetry using a fisheye camera and a structured light system to map the internal geometry of pipelines by generating a photorealistic, geometrically accurate surface model. The error of the system output was evaluated through comparison to a ground truth laser scan (ATOS GOM Triple Scan) of a nuclear grade split pipe sample (stainless steel 304L, 80mm internal diameter) containing defects representative of the application - the error was found to be submillimeter across the sample.

  1. Deficits in vision and visual attention associated with motor performance of very preterm/very low birth weight children.

    PubMed

    Geldof, Christiaan J A; van Hus, Janeline W P; Jeukens-Visser, Martine; Nollet, Frans; Kok, Joke H; Oosterlaan, Jaap; van Wassenaer-Leemhuis, Aleid G

    2016-01-01

    To extend understanding of impaired motor functioning of very preterm (VP)/very low birth weight (VLBW) children by investigating its relationship with visual attention, visual and visual-motor functioning. Motor functioning (Movement Assessment Battery for Children, MABC-2; Manual Dexterity, Aiming & Catching, and Balance component), as well as visual attention (attention network and visual search tests), vision (oculomotor, visual sensory and perceptive functioning), visual-motor integration (Beery Visual Motor Integration), and neurological status (Touwen examination) were comprehensively assessed in a sample of 106 5.5-year-old VP/VLBW children. Stepwise linear regression analyses were conducted to investigate multivariate associations between deficits in visual attention, oculomotor, visual sensory, perceptive and visual-motor integration functioning, abnormal neurological status, neonatal risk factors, and MABC-2 scores. Abnormal MABC-2 Total or component scores occurred in 23-36% of VP/VLBW children. Visual and visual-motor functioning accounted for 9-11% of variance in MABC-2 Total, Manual Dexterity and Balance scores. Visual perceptive deficits only were associated with Aiming & Catching. Abnormal neurological status accounted for an additional 19-30% of variance in MABC-2 Total, Manual Dexterity and Balance scores, and 5% of variance in Aiming & Catching, and neonatal risk factors for 3-6% of variance in MABC-2 Total, Manual Dexterity and Balance scores. Motor functioning is weakly associated with visual and visual-motor integration deficits and moderately associated with abnormal neurological status, indicating that motor performance reflects long term vulnerability following very preterm birth, and that visual deficits are of minor importance in understanding motor functioning of VP/VLBW children. Copyright © 2016 Elsevier Ltd. All rights reserved.

  2. Abnormal center-periphery gradient in spatial attention in simultanagnosia.

    PubMed

    Balslev, Daniela; Odoj, Bartholomaeus; Rennig, Johannes; Karnath, Hans-Otto

    2014-12-01

    Patients suffering from simultanagnosia cannot perceive more than one object at a time. The underlying mechanism is incompletely understood. One hypothesis is that simultanagnosia reflects "tunnel vision," a constricted attention window around gaze, which precludes the grouping of individual objects. Although this idea has a long history in neuropsychology, the question whether the patients indeed have an abnormal attention gradient around the gaze has so far not been addressed. Here we tested this hypothesis in two simultanagnosia patients with bilateral parieto-occipital lesions and two control groups, with and without brain damage. We assessed the participants' ability to discriminate letters presented briefly at fixation with and without a peripheral distractor or in the visual periphery, with or without a foveal distractor. A constricted span of attention around gaze would predict an increased susceptibility to foveated versus peripheral distractors. Contrary to this prediction and unlike both control groups, the patients' ability to discriminate the target decreased more in the presence of peripheral compared with foveated distractors. Thus, the attentional spotlight in simultanagnosia does not fall on foveated objects as previously assumed, but rather abnormally highlights the periphery. Furthermore, we found the same center-periphery gradient in the patients' ability to recognize multiple objects. They detected multiple, but not single objects more accurately in the periphery than at fixation. These results suggest that an abnormal allocation of attention around the gaze can disrupt the grouping of individual objects into an integrated visual scene.

  3. Visual cortex in dementia with Lewy bodies: magnetic resonance imaging study

    PubMed Central

    Taylor, John-Paul; Firbank, Michael J.; He, Jiabao; Barnett, Nicola; Pearce, Sarah; Livingstone, Anthea; Vuong, Quoc; McKeith, Ian G.; O’Brien, John T.

    2012-01-01

    Background Visual hallucinations and visuoperceptual deficits are common in dementia with Lewy bodies, suggesting that cortical visual function may be abnormal. Aims To investigate: (1) cortical visual function using functional magnetic resonance imaging (fMRI); and (2) the nature and severity of perfusion deficits in visual areas using arterial spin labelling (ASL)-MRI. Method In total, 17 participants with dementia with Lewy bodies (DLB group) and 19 similarly aged controls were presented with simple visual stimuli (checkerboard, moving dots, and objects) during fMRI and subsequently underwent ASL-MRI (DLB group n = 15, control group n = 19). Results Functional activations were evident in visual areas in both the DLB and control groups in response to checkerboard and objects stimuli but reduced visual area V5/MT (middle temporal) activation occurred in the DLB group in response to motion stimuli. Posterior cortical perfusion deficits occurred in the DLB group, particularly in higher visual areas. Conclusions Higher visual areas, particularly occipito-parietal, appear abnormal in dementia with Lewy bodies, while there is a preservation of function in lower visual areas (V1 and V2/3). PMID:22500014

  4. Scientific & Intelligence Exascale Visualization Analysis System

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Money, James H.

    SIEVAS provides an immersive visualization framework for connecting multiple systems in real time for data science. SIEVAS provides the ability to connect multiple COTS and GOTS products in a seamless fashion for data fusion, data analysis, and viewing. It provides this capability by using a combination of micro services, real time messaging, and web service compliant back-end system.

  5. A Novel System for Visualizing Alphavirus Assembly

    PubMed Central

    Steel, J. Jordan; Geiss, Brian J.

    2015-01-01

    Alphaviruses are small, enveloped RNA viruses that form infectious particles by budding through the cellular plasma membrane. To help visualize and understand the intracellular assembly of alphavirus virions we have developed a bimolecular fluorescence complementation-based system (BiFC) that allows visualization of capsid and E2 subcellular localization and association in live cells. In this system, N- or C-terminal Venus fluorescent protein fragments (VN- and VC-) are fused to the N-terminus of the capsid protein on the Sindbis virus structural polyprotein, which results in the formation of fluorescent capsid-like structures in the absence of viral genomes that associate with the plasma membrane of cells. Mutation of the capsid autoprotease active site blocks structural polyprotein processing and alters the subcellular distribution of capsid fluorescence. Incorporating mCherry into the extracellular domain of the E2 glycoprotein allows the visualization of E2 glycoprotein localization and showed a close association of the E2 and capsid proteins at the plasma membrane as expected. These results suggest that this system is a useful new tool to study alphavirus assembly in live cells and may be useful in identifying molecules that inhibit alphavirus virion formation. PMID:26122073

  6. Retinal Layer Abnormalities as Biomarkers of Schizophrenia.

    PubMed

    Samani, Niraj N; Proudlock, Frank A; Siram, Vasantha; Suraweera, Chathurie; Hutchinson, Claire; Nelson, Christopher P; Al-Uzri, Mohammed; Gottlob, Irene

    2018-06-06

    Schizophrenia is associated with several brain deficits, as well as visual processing deficits, but clinically useful biomarkers are elusive. We hypothesized that retinal layer changes, noninvasively visualized using spectral-domain optical coherence tomography (SD-OCT), may represent a possible "window" to these abnormalities. A Leica EnvisuTM SD-OCT device was used to obtain high-resolution central foveal B-scans in both eyes of 35 patients with schizophrenia and 50 demographically matched controls. Manual retinal layer segmentation was performed to acquire individual and combined layer thickness measurements in 3 macular regions. Contrast sensitivity was measured at 3 spatial frequencies in a subgroup of each cohort. Differences were compared using adjusted linear models and significantly different layer measures in patients underwent Spearman Rank correlations with contrast sensitivity, quantified symptoms severity, disease duration, and antipsychotic medication dose. Total retinal and photoreceptor complex thickness was reduced in all regions in patients (P < .0001). Segmentation revealed consistent thinning of the outer nuclear layer (P < .001) and inner segment layer (P < .05), as well as a pattern of parafoveal ganglion cell changes. Low spatial frequency contrast sensitivity was reduced in patients (P = .002) and correlated with temporal parafoveal ganglion cell complex thinning (R = .48, P = .01). Negative symptom severity was inversely correlated with foveal photoreceptor complex thickness (R = -.54, P = .001) and outer nuclear layer thickness (R = -.47, P = .005). Our novel findings demonstrate considerable retinal layer abnormalities in schizophrenia that are related to clinical features and visual function. With time, SD-OCT could provide easily-measurable biomarkers to facilitate clinical assessment and further our understanding of the disease.

  7. Towards a visual modeling approach to designing microelectromechanical system transducers

    NASA Astrophysics Data System (ADS)

    Dewey, Allen; Srinivasan, Vijay; Icoz, Evrim

    1999-12-01

    In this paper, we address initial design capture and system conceptualization of microelectromechanical system transducers based on visual modeling and design. Visual modeling frames the task of generating hardware description language (analog and digital) component models in a manner similar to the task of generating software programming language applications. A structured topological design strategy is employed, whereby microelectromechanical foundry cell libraries are utilized to facilitate the design process of exploring candidate cells (topologies), varying key aspects of the transduction for each topology, and determining which topology best satisfies design requirements. Coupled-energy microelectromechanical system characterizations at a circuit level of abstraction are presented that are based on branch constitutive relations and an overall system of simultaneous differential and algebraic equations. The resulting design methodology is called visual integrated-microelectromechanical VHDL-AMS interactive design (VHDL-AMS is visual hardware design language for analog and mixed signal).

  8. Subclinical visual involvement in multiple sclerosis: a study by MRI, VEPs, frequency-doubling perimetry, standard perimetry, and contrast sensitivity.

    PubMed

    Sisto, Dario; Trojano, Maria; Vetrugno, Michele; Trabucco, Tiziana; Iliceto, Giovanni; Sborgia, Carlo

    2005-04-01

    To evaluate the effectiveness of visual evoked potentials (VEPs), frequency-doubling perimetry (FDP), standard achromatic perimetry (SAP), contrast sensitivity (CS) test, and magnetic resonance imaging (MRI), isolated or in combination, in detecting subclinical impairment of visual function in multiple sclerosis (MS). Twenty-two eyes of 11 patients affected by clinically definite MS, without a history of optic neuritis and asymptomatic for visual disturbances, underwent full ophthalmic examination and, in addition, VEPs, FDP, SAP, CS, and MRI. Abnormal results were taken to be as follows: for VEPs, a P100 latency >115 ms; for FDP, abnormal mean deviation (MD) or pattern SD (PSD); for SAP, abnormal MD or PSD; for CS, abnormal CS at one spatial frequency, at least; and for MRI, evidence of at least one demyelinating plaque along the visual pathway. VEPs showed abnormal results in 12 eyes (54.4%), FDP in 11 (50%), SAP in 14 (63.6%), CS in 17 (77.1%), and MRI in 16 (72.7%). In only two (9.1%) eyes of the same patient was no abnormality found. No single test detected all the abnormal eyes. Four (18.2%) eyes had pure optic nerve involvement and the remaining 16 (72.7%) had both pre- and postchiasmal involvement. In patients affected by clinically definite MS without history of optic neuritis and no visual symptoms, there is a large prevalence of visual pathway involvement that can be diagnosed only by performing multiple tests. The comparison of the tests is also useful to detect the presence of multiple lesions in the same patient.

  9. Physiologic abnormalities of cardiac function in progressive systemic sclerosis with diffuse scleroderma

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Follansbee, W.P.; Curtiss, E.I.; Medsger, T.A. Jr.

    1984-01-19

    To investigate cardiopulmonary function in progressive systemic sclerosis with diffuse scleroderma, we studied 26 patients with maximal exercise and redistribution thallium scans, rest and exercise radionuclide ventriculography, pulmonary-function testing, and chest roentgenography. Although only 6 patients had clinical evidence of cardiac involvement, 20 had abnormal thallium scans, including 10 with reversible exercise-induced defects and 18 with fixed defects (8 had both). Seven of the 10 patients who had exercise-induced defects and underwent cardiac catheterization had normal coronary angiograms. Mean resting left ventricular ejection fraction and mean resting right ventricular ejection fraction were lower in patients with post-exercise left ventricular thalliummore » defect scores above the median (59 +/- 13 per cent vs. 69 +/- 6 per cent, and 36 +/- 12 per cent vs. 47 +/- 7 per cent, respectively). The authors conclude that in progressive systemic sclerosis with diffuse scleroderma, abnormalities of myocardial perfusion are common and appear to be due to a disturbance of the myocardial microcirculation. Both right and left ventricular dysfunction appear to be related to this circulatory disturbance, suggesting ischemically mediated injury.« less

  10. Visual impairment evaluation in 119 children with congenital Zika syndrome.

    PubMed

    Ventura, Liana O; Ventura, Camila V; Dias, Natália de C; Vilar, Isabelle G; Gois, Adriana L; Arantes, Tiago E; Fernandes, Luciene C; Chiang, Michael F; Miller, Marilyn T; Lawrence, Linda

    2018-06-01

    To assess visual impairment in a large sample of infants with congenital Zika syndrome (CZS) and to compare with a control group using the same assessment protocol. The study group was composed of infants with confirmed diagnosis of CZS. Controls were healthy infants matched for age, sex, and socioeconomic status. All infants underwent comprehensive ophthalmologic evaluation including visual acuity, visual function assessment, and visual developmental milestones. The CZS group included 119 infants; the control group, 85 infants. At examination, the mean age of the CZS group was 8.5 ± 1.2 months (range, 6-13 months); of the controls, 8.4 ± 1.8 months (range, 5-12 months; P = 0.598). Binocular Teller Acuity Card (TAC) testing was abnormal in 107 CZS infants and in 4 controls (89.9% versus 5% [P < 0.001]). In the study group, abnormal monocular TAC results were more frequent in eyes with funduscopic alterations (P = 0.008); however, 104 of 123 structurally normal eyes (84.6%) also presented abnormal TAC results. Binocular contrast sensitivity was reduced in 87 of 107 CZS infants and in 8 of 80 controls (81.3% versus 10% [P < 0.001]). The visual development milestones were less achieved by infants with CZS compared to controls (P < 0.001). Infants with CZS present with severe visual impairment. A protocol for assessment of the ocular findings, visual acuity, and visual developmental milestones tested against age-matched controls is suggested. Copyright © 2018 American Association for Pediatric Ophthalmology and Strabismus. Published by Elsevier Inc. All rights reserved.

  11. The FIGO systems for nomenclature and classification of causes of abnormal uterine bleeding in the reproductive years: who needs them?

    PubMed

    Munro, Malcolm G; Critchley, Hilary O D; Fraser, Ian S

    2012-10-01

    In November 2010, the International Federation of Gynecology and Obstetrics formally accepted a new classification system for causes of abnormal uterine bleeding in the reproductive years. The system, based on the acronym PALM-COEIN (polyps, adenomyosis, leiomyoma, malignancy and hyperplasia-coagulopathy, ovulatory disorders, endometrial causes, iatrogenic, not classified) was developed in response to concerns about the design and interpretation of basic science and clinical investigation that relates to the problem of abnormal uterine bleeding. A system of nomenclature for the description of normal uterine bleeding and the various symptoms that comprise abnormal bleeding has also been included. This article describes the rationale, the structured methods that involved stakeholders worldwide, and the suggested use of the International Federation of Gynecology and Obstetrics system for research, education, and clinical care. Investigators in the field are encouraged to use the system in the design of their abnormal uterine bleeding-related research because it is an approach that should improve our understanding and management of this often perplexing clinical condition. Copyright © 2012. Published by Mosby, Inc.

  12. Major Electrocardiographic Abnormalities According to the Minnesota Coding System Among Brazilian Adults (from the ELSA-Brasil Cohort Study).

    PubMed

    Pinto-Filho, Marcelo M; Brant, Luisa C C; Foppa, Murilo; Garcia-Silva, Kaiser B; Mendes de Oliveira, Rackel Aguiar; de Jesus Mendes da Fonseca, Maria; Alvim, Sheila; Lotufo, Paulo A; Mill, José G; Barreto, Sandhi M; Macfarlane, Peter W; Ribeiro, Antonio L P

    2017-06-15

    The electrocardiogram is a simple and useful clinical tool; nevertheless, few studies have evaluated the prevalence of electrocardiographic abnormalities in the Latin American population. This study aims to evaluate the major electrocardiographic abnormalities according to the Minnesota coding system in Brazilian adults, stratified by gender, age, race, and cardiovascular risk factors. Data from 14,424 adults (45.8% men, age 35 to 74 years) were obtained at baseline of the Brazilian Longitudinal Study of Adult Health (ELSA-Brasil), according to standardized protocol. The electrocardiogram were obtained with the Burdick Atria 6100 machine, stored on Pyramis System, automatically coded according to the Minnesota coding system by the Glasgow University software and then manually revised. Major abnormalities were more prevalent in men than women (11.3% and 7.9%, p <0.001). These differences were consistent through the different age groups, race, and number of cardiovascular risk factors. Electrocardiographic major abnormalities were more prevalent in black participants for both men (black: 15.1%, mixed: 10.4%, white: 11.1%, p = 0.001) and women (black: 10%, mixed: 7.6%, white: 7.2%, p = 0.004). In conclusion, in this large sample of Brazilian adults, the prevalence of major electrocardiographic abnormalities was higher among men, the elderly, black, and among people with more cardiovascular risk factors. Copyright © 2017 Elsevier Inc. All rights reserved.

  13. Abnormal brain activation in neurofibromatosis type 1: a link between visual processing and the default mode network.

    PubMed

    Violante, Inês R; Ribeiro, Maria J; Cunha, Gil; Bernardino, Inês; Duarte, João V; Ramos, Fabiana; Saraiva, Jorge; Silva, Eduardo; Castelo-Branco, Miguel

    2012-01-01

    Neurofibromatosis type 1 (NF1) is one of the most common single gene disorders affecting the human nervous system with a high incidence of cognitive deficits, particularly visuospatial. Nevertheless, neurophysiological alterations in low-level visual processing that could be relevant to explain the cognitive phenotype are poorly understood. Here we used functional magnetic resonance imaging (fMRI) to study early cortical visual pathways in children and adults with NF1. We employed two distinct stimulus types differing in contrast and spatial and temporal frequencies to evoke relatively different activation of the magnocellular (M) and parvocellular (P) pathways. Hemodynamic responses were investigated in retinotopically-defined regions V1, V2 and V3 and then over the acquired cortical volume. Relative to matched control subjects, patients with NF1 showed deficient activation of the low-level visual cortex to both stimulus types. Importantly, this finding was observed for children and adults with NF1, indicating that low-level visual processing deficits do not ameliorate with age. Moreover, only during M-biased stimulation patients with NF1 failed to deactivate or even activated anterior and posterior midline regions of the default mode network. The observation that the magnocellular visual pathway is impaired in NF1 in early visual processing and is specifically associated with a deficient deactivation of the default mode network may provide a neural explanation for high-order cognitive deficits present in NF1, particularly visuospatial and attentional. A link between magnocellular and default mode network processing may generalize to neuropsychiatric disorders where such deficits have been separately identified.

  14. Rise and fall of the two visual systems theory.

    PubMed

    Rossetti, Yves; Pisella, Laure; McIntosh, Robert D

    2017-06-01

    Among the many dissociations describing the visual system, the dual theory of two visual systems, respectively dedicated to perception and action, has yielded a lot of support. There are psychophysical, anatomical and neuropsychological arguments in favor of this theory. Several behavioral studies that used sensory and motor psychophysical parameters observed differences between perceptive and motor responses. The anatomical network of the visual system in the non-human primate was very readily organized according to two major pathways, dorsal and ventral. Neuropsychological studies, exploring optic ataxia and visual agnosia as characteristic deficits of these two pathways, led to the proposal of a functional double dissociation between visuomotor and visual perceptual functions. After a major wave of popularity that promoted great advances, particularly in knowledge of visuomotor functions, the guiding theory is now being reconsidered. Firstly, the idea of a double dissociation between optic ataxia and visual form agnosia, as cleanly separating visuomotor from visual perceptual functions, is no longer tenable; optic ataxia does not support a dissociation between perception and action and might be more accurately viewed as a negative image of action blindsight. Secondly, dissociations between perceptive and motor responses highlighted in the framework of this theory concern a very elementary level of action, even automatically guided action routines. Thirdly, the very rich interconnected network of the visual brain yields few arguments in favor of a strict perception/action dissociation. Overall, the dissociation between motor function and perceptive function explored by these behavioral and neuropsychological studies can help define an automatic level of action organization deficient in optic ataxia and preserved in action blindsight, and underlines the renewed need to consider the perception-action circle as a functional ensemble. Copyright © 2017 Elsevier

  15. Changes of Visual Pathway and Brain Connectivity in Glaucoma: A Systematic Review

    PubMed Central

    Nuzzi, Raffaele; Dallorto, Laura; Rolle, Teresa

    2018-01-01

    Background: Glaucoma is a leading cause of irreversible blindness worldwide. The increasing interest in the involvement of the cortical visual pathway in glaucomatous patients is due to the implications in recent therapies, such as neuroprotection and neuroregeneration. Objective: In this review, we outline the current understanding of brain structural, functional, and metabolic changes detected with the modern techniques of neuroimaging in glaucomatous subjects. Methods: We screened MEDLINE, EMBASE, CINAHL, CENTRAL, LILACS, Trip Database, and NICE for original contributions published until 31 October 2017. Studies with at least six patients affected by any type of glaucoma were considered. We included studies using the following neuroimaging techniques: functional Magnetic Resonance Imaging (fMRI), resting-state fMRI (rs-fMRI), magnetic resonance spectroscopy (MRS), voxel- based Morphometry (VBM), surface-based Morphometry (SBM), diffusion tensor MRI (DTI). Results: Over a total of 1,901 studies, 56 case series with a total of 2,381 patients were included. Evidence of neurodegenerative process in glaucomatous patients was found both within and beyond the visual system. Structural alterations in visual cortex (mainly reduced cortex thickness and volume) have been demonstrated with SBM and VBM; these changes were not limited to primary visual cortex but also involved association visual areas. Other brain regions, associated with visual function, demonstrated a certain grade of increased or decreased gray matter volume. Functional and metabolic abnormalities resulted within primary visual cortex in all studies with fMRI and MRS. Studies with rs-fMRI found disrupted connectivity between the primary and higher visual cortex and between visual cortex and associative visual areas in the task-free state of glaucomatous patients. Conclusions: This review contributes to the better understanding of brain abnormalities in glaucoma. It may stimulate further speculation about

  16. Single and Multiple Visual Systems in Arthropods

    PubMed Central

    Wald, George

    1968-01-01

    Extraction of two visual pigments from crayfish eyes prompted an electrophysiological examination of the role of visual pigments in the compound eyes of six arthropods. The intact animals were used; in crayfishes isolated eyestalks also. Thresholds were measured in terms of the absolute or relative numbers of photons per flash at various wavelengths needed to evoke a constant amplitude of electroretinogram, usually 50 µv. Two species of crayfish, as well as the green crab, possess blue- and red-sensitive receptors apparently arranged for color discrimination. In the northern crayfish, Orconectes virilis, the spectral sensitivity of the dark-adapted eye is maximal at about 550 mµ, and on adaptation to bright red or blue lights breaks into two functions with λmax respectively at about 435 and 565 mµ, apparently emanating from different receptors. The swamp crayfish, Procambarus clarkii, displays a maximum sensitivity when dark-adapted at about 570 mµ, that breaks on color adaptation into blue- and red-sensitive functions with λmax about 450 and 575 mµ, again involving different receptors. Similarly the green crab, Carcinides maenas, presents a dark-adapted sensitivity maximal at about 510 mµ that divides on color adaptation into sensitivity curves maximal near 425 and 565 mµ. Each of these organisms thus possesses an apparatus adequate for at least two-color vision, resembling that of human green-blinds (deuteranopes). The visual pigments of the red-sensitive systems have been extracted from the crayfish eyes. The horse-shoe crab, Limulus, and the lobster each possesses a single visual system, with λmax respectively at 520 and 525 mµ. Each of these is invariant with color adaptation. In each case the visual pigment had already been identified in extracts. The spider crab, Libinia emarginata, presents another variation. It possesses two visual systems apparently differentiated, not for color discrimination but for use in dim and bright light, like

  17. Retinal adaptation abnormalities in primary open-angle glaucoma.

    PubMed

    Dul, Mitchell; Ennis, Robert; Radner, Shira; Lee, Barry; Zaidi, Qasim

    2015-01-22

    Dynamic color and brightness adaptation are crucial for visual functioning. The effects of glaucoma on retinal ganglion cells (RGCs) could compromise these functions. We have previously used slow dynamic changes of light at moderate intensities to measure the speed and magnitude of subtractive adaptation in RGCs. We used the same procedure to test if RGC abnormalities cause slower and weaker adaptation for patients with glaucoma when compared to age-similar controls. We assessed adaptation deficits in specific classes of RGCs by testing along the three cardinal color axes that isolate konio, parvo, and magno RGCs. For one eye each of 10 primary open-angle glaucoma patients and their age-similar controls, we measured the speed and magnitude of adapting to 1/32 Hz color modulations along the three cardinal axes, at central fixation and 8° superior, inferior, nasal, and temporal to fixation. In all 15 comparisons (5 locations × 3 color axes), average adaptation was slower and weaker for glaucoma patients than for controls. Adaptation developed slower at central targets than at 8° eccentricities for controls, but not for patients. Adaptation speed and magnitude differed between affected and control eyes even at retinal locations showing no visual field loss with clinical perimetry. Neural adaptation is weaker in glaucoma patients for all three classes of RGCs. Since adaptation abnormalities are manifested even at retinal locations not exhibiting a visual field loss, this novel form of assessment may offer a functional insight into glaucoma and an early diagnosis tool. Copyright 2015 The Association for Research in Vision and Ophthalmology, Inc.

  18. Retinal Adaptation Abnormalities in Primary Open-Angle Glaucoma

    PubMed Central

    Dul, Mitchell; Ennis, Robert; Radner, Shira; Lee, Barry; Zaidi, Qasim

    2015-01-01

    Purpose. Dynamic color and brightness adaptation are crucial for visual functioning. The effects of glaucoma on retinal ganglion cells (RGCs) could compromise these functions. We have previously used slow dynamic changes of light at moderate intensities to measure the speed and magnitude of subtractive adaptation in RGCs. We used the same procedure to test if RGC abnormalities cause slower and weaker adaptation for patients with glaucoma when compared to age-similar controls. We assessed adaptation deficits in specific classes of RGCs by testing along the three cardinal color axes that isolate konio, parvo, and magno RGCs. Methods. For one eye each of 10 primary open-angle glaucoma patients and their age-similar controls, we measured the speed and magnitude of adapting to 1/32 Hz color modulations along the three cardinal axes, at central fixation and 8° superior, inferior, nasal, and temporal to fixation. Results. In all 15 comparisons (5 locations × 3 color axes), average adaptation was slower and weaker for glaucoma patients than for controls. Adaptation developed slower at central targets than at 8° eccentricities for controls, but not for patients. Adaptation speed and magnitude differed between affected and control eyes even at retinal locations showing no visual field loss with clinical perimetry. Conclusions. Neural adaptation is weaker in glaucoma patients for all three classes of RGCs. Since adaptation abnormalities are manifested even at retinal locations not exhibiting a visual field loss, this novel form of assessment may offer a functional insight into glaucoma and an early diagnosis tool. PMID:25613950

  19. [Electrocardiographic abnormalities in acute olanzapine poisonings].

    PubMed

    Ciszowski, Krzysztof; Sein Anand, Jacek

    2011-01-01

    Olanzapine is an atypical antipsychotic used for many years in the treatment of schizophrenia and bipolar disorder. Poisonings with this medicine can results with cardiotoxic effects in the form of ECG abnormalities. To evaluate the nature and incidence of electrocardiographic abnormalities in patients with acute olanzapine poisoning. 23 adult (mean age 38.4 +/- 15.5 years) patients with acute olanzapine poisoning, including 10 men (30.4 +/- 8.1 years) and 11 women (45.7 +/- 17.2 years), where 1 man and 1 woman were poisoned twice. The toxic serum level of olanzapine (above 100 ng/mL) was confirmed in each patient. Evaluation of electrocardiograms performed in patients in the first day of hospitalization with automatic measurement of durations of PQ, QRS and QTc and the identification of arrhythmias and conduction disorders on the basis of visual analysis of the ECG waveforms. Statistical analysis of the results using the methods of descriptive statistics. The mean durations of PQ, QRS and QTc in the study group were as follows: 135 +/- 23 ms, 91 +/- 12 ms, and 453 +/- 48 ms, respectively. The most common ECG abnormalities were prolonged QTc and supraventricular tachycardia (including sinus tachycardia) - each 22%; less common were ST-T changes (17%) and supraventricular premature complexes (9%), and only in individual cases (4%) ventricular premature complexes, bundle branch block, sinus bradycardia and atrial fibrillation were present. In the course of acute olanzapine poisonings: (1) prolonged QTc interval is quite common, but rarely leads to torsade de pointes tachycardia; (2) fast supraventricular rhythms are also common, but rarely cause irregular tachyarrhythmias, eg. atrial fibrillation; (3) conduction disorders (atrioventricular blocks, bundle branch blocks) are not typical abnormalities; (4) the observed ECG abnormalities emphasize the need of continuous ECG monitoring in these patients.

  20. Immune function and brain abnormalities in patients with systemic lupus erythematosus without overt neuropsychiatric manifestations.

    PubMed

    Kozora, E; Filley, C M; Zhang, L; Brown, M S; Miller, D E; Arciniegas, D B; Pelzman, J L; West, S G

    2012-04-01

    This study examined the relationship between immune, cognitive and neuroimaging assessments in subjects with systemic lupus erythematosus (SLE) without histories of overt neuropsychiatric (NP) disorders. In total, 84 subjects with nonNPSLE and 37 healthy controls completed neuropsychological testing from the American College of Rheumatology SLE battery. Serum autoantibody and cytokine measures, volumetric magnetic resonance imaging, and magnetic resonance spectroscopy data were collected on a subset of subjects. NonNPSLE subjects had lower scores on measures of visual/complex attention, visuomotor speed and verbal memory compared with controls. No clinically significant differences between nonNPSLE patients and controls were found on serum measures of lupus anticoagulant, anticardiolipin antibodies, beta 2-glycoproteins, or pro-inflammatory cytokines (interleukin (IL)-1, IL-6, interferon alpha (IFN-alpha), and interferon gamma (IFN-gamma)). Higher scores on a global cognitive impairment index and a memory impairment index were correlated with lower IFN-alpha. Few associations between immune functions and neuroimaging parameters were found. Results indicated that nonNPSLE patients demonstrated cognitive impairment but not immune differences compared with controls. In these subjects, who were relatively young and with mild disease, no relationship between cognitive dysfunction, immune parameters, or previously documented neuroimaging abnormalities were noted. Immune measures acquired from cerebrospinal fluid instead of serum may yield stronger associations.

  1. GVS - GENERAL VISUALIZATION SYSTEM

    NASA Technical Reports Server (NTRS)

    Keith, S. R.

    1994-01-01

    The primary purpose of GVS (General Visualization System) is to support scientific visualization of data output by the panel method PMARC_12 (inventory number ARC-13362) on the Silicon Graphics Iris computer. GVS allows the user to view PMARC geometries and wakes as wire frames or as light shaded objects. Additionally, geometries can be color shaded according to phenomena such as pressure coefficient or velocity. Screen objects can be interactively translated and/or rotated to permit easy viewing. Keyframe animation is also available for studying unsteady cases. The purpose of scientific visualization is to allow the investigator to gain insight into the phenomena they are examining, therefore GVS emphasizes analysis, not artistic quality. GVS uses existing IRIX 4.0 image processing tools to allow for conversion of SGI RGB files to other formats. GVS is a self-contained program which contains all the necessary interfaces to control interaction with PMARC data. This includes 1) the GVS Tool Box, which supports color histogram analysis, lighting control, rendering control, animation, and positioning, 2) GVS on-line help, which allows the user to access control elements and get information about each control simultaneously, and 3) a limited set of basic GVS data conversion filters, which allows for the display of data requiring simpler data formats. Specialized controls for handling PMARC data include animation and wakes, and visualization of off-body scan volumes. GVS is written in C-language for use on SGI Iris series computers running IRIX. It requires 28Mb of RAM for execution. Two separate hardcopy documents are available for GVS. The basic document price for ARC-13361 includes only the GVS User's Manual, which outlines major features of the program and provides a tutorial on using GVS with PMARC_12 data. Programmers interested in modifying GVS for use with data in formats other than PMARC_12 format may purchase a copy of the draft GVS 3.1 Software Maintenance

  2. Visual prosthesis wireless energy transfer system optimal modeling.

    PubMed

    Li, Xueping; Yang, Yuan; Gao, Yong

    2014-01-16

    Wireless energy transfer system is an effective way to solve the visual prosthesis energy supply problems, theoretical modeling of the system is the prerequisite to do optimal energy transfer system design. On the basis of the ideal model of the wireless energy transfer system, according to visual prosthesis application condition, the system modeling is optimized. During the optimal modeling, taking planar spiral coils as the coupling devices between energy transmitter and receiver, the effect of the parasitic capacitance of the transfer coil is considered, and especially the concept of biological capacitance is proposed to consider the influence of biological tissue on the energy transfer efficiency, resulting in the optimal modeling's more accuracy for the actual application. The simulation data of the optimal model in this paper is compared with that of the previous ideal model, the results show that under high frequency condition, the parasitic capacitance of inductance and biological capacitance considered in the optimal model could have great impact on the wireless energy transfer system. The further comparison with the experimental data verifies the validity and accuracy of the optimal model proposed in this paper. The optimal model proposed in this paper has a higher theoretical guiding significance for the wireless energy transfer system's further research, and provide a more precise model reference for solving the power supply problem in visual prosthesis clinical application.

  3. Abnormal Microstructure of the Atrophic Thalamus in Preterm Survivors with Periventricular Leukomalacia

    PubMed Central

    Nagasunder, A.C.; Kinney, H.C.; Blüml, S.; Tavaré, C.J.; Rosser, T.; Gilles, F.H.; Nelson, M.D.; Panigrahy, A.

    2012-01-01

    BACKGROUND AND PURPOSE The neuroanatomic substrate of cognitive deficits in long-term survivors of prematurity with PVL is poorly understood. The thalamus is critically involved in cognition via extensive interconnections with the cerebral cortex. We hypothesized that the thalamus is atrophic (reduced in volume) in childhood survivors of prematurity with neuroimaging evidence of PVL and that the atrophy is associated with selective microstructural abnormalities within its subdivisions. MATERIALS AND METHODS We performed quantitative volumetric and DTI measurements of the thalamus in 17 children with neuroimaging evidence of PVL (mean postconceptional age, 5.6 ± 4.0 years) who were born prematurely and compared these with 74 term control children (5.7 ± 3.4 years). RESULTS The major findings were the following: 1) a significant reduction in the overall volume of the thalamus in patients with PVL compared with controls (P < .0001), which also correlated with the severity of PVL (P = .001); 2) significantly decreased FA (P = .003) and increased λ⊥ (P = .02) in the thalamus overall and increased axial, radial, and mean diffusivities in the pulvinar (P < .03), suggesting injury to afferent and efferent myelinated axons; and 3) a positive correlation of pulvinar abnormalities with those of the parieto-occipital white matter in periventricular leukomalacia, suggesting that the pulvinar abnormalities reflect secondary effects of damaged interconnections between the pulvinar and parieto-occipital cortices in the cognitive visual network. CONCLUSIONS There are volumetric and microstructural abnormalities of the thalamus in preterm children with PVL, very likely reflecting neuronal loss and myelinated axonal injury. The selective microstructural damage in the pulvinar very likely contributes to abnormal cognitive visual processing known to occur in such survivors. PMID:20930003

  4. Holodeck: Telepresence Dome Visualization System Simulations

    NASA Technical Reports Server (NTRS)

    Hite, Nicolas

    2012-01-01

    This paper explores the simulation and consideration of different image-projection strategies for the Holodeck, a dome that will be used for highly immersive telepresence operations in future endeavors of the National Aeronautics and Space Administration (NASA). Its visualization system will include a full 360 degree projection onto the dome's interior walls in order to display video streams from both simulations and recorded video. Because humans innately trust their vision to precisely report their surroundings, the Holodeck's visualization system is crucial to its realism. This system will be rigged with an integrated hardware and software infrastructure-namely, a system of projectors that will relay with a Graphics Processing Unit (GPU) and computer to both project images onto the dome and correct warping in those projections in real-time. Using both Computer-Aided Design (CAD) and ray-tracing software, virtual models of various dome/projector geometries were created and simulated via tracking and analysis of virtual light sources, leading to the selection of two possible configurations for installation. Research into image warping and the generation of dome-ready video content was also conducted, including generation of fisheye images, distortion correction, and the generation of a reliable content-generation pipeline.

  5. Neuroanatomical affiliation visualization-interface system.

    PubMed

    Palombi, Olivier; Shin, Jae-Won; Watson, Charles; Paxinos, George

    2006-01-01

    A number of knowledge management systems have been developed to allow users to have access to large quantity of neuroanatomical data. The advent of three-dimensional (3D) visualization techniques allows users to interact with complex 3D object. In order to better understand the structural and functional organization of the brain, we present Neuroanatomical Affiliations Visualization-Interface System (NAVIS) as the original software to see brain structures and neuroanatomical affiliations in 3D. This version of NAVIS has made use of the fifth edition of "The Rat Brain in Stereotaxic coordinates" (Paxinos and Watson, 2005). The NAVIS development environment was based on the scripting language name Python, using visualization toolkit (VTK) as 3D-library and wxPython for the graphic user interface. The following manuscript is focused on the nucleus of the solitary tract (Sol) and the set of affiliated structures in the brain to illustrate the functionality of NAVIS. The nucleus of the Sol is the primary relay center of visceral and taste information, and consists of 14 distinct subnuclei that differ in cytoarchitecture, chemoarchitecture, connections, and function. In the present study, neuroanatomical projection data of the rat Sol were collected from selected literature in PubMed since 1975. Forty-nine identified projection data of Sol were inserted in NAVIS. The standard XML format used as an input for affiliation data allows NAVIS to update data online and/or allows users to manually change or update affiliation data. NAVIS can be extended to nuclei other than Sol.

  6. Nervous system disruption and concomitant behavioral abnormality in early hatched pufferfish larvae exposed to heavy oil.

    PubMed

    Kawaguchi, Masahumi; Sugahara, Yuki; Watanabe, Tomoe; Irie, Kouta; Ishida, Minoru; Kurokawa, Daisuke; Kitamura, Shin-Ichi; Takata, Hiromi; Handoh, Itsuki C; Nakayama, Kei; Murakami, Yasunori

    2011-08-01

    Spills of heavy oil (HO) over the oceans have been proven to have an adverse effect on marine life. It has been hypothesized that exposure of early larvae of sinking eggs to HO leads largely to normal morphology, whereas abnormal organization of the developing neural scaffold is likely to be found. HO-induced disruption of the nervous system, which controls animal behavior, may in turn cause abnormalities in the swimming behavior of hatched larvae. To clarify the toxicological effects of HO, we performed exposure experiments and morphological and behavioral analyses in pufferfish (Takifugu rubripes) larvae. Fertilized eggs of pufferfish were exposed to 50 mg/L of HO for 8 days and transferred to fresh seawater before hatching. The hatched larvae were observed for their swimming behavior, morphological appearance, and construction of muscles and nervous system. In HO-exposed larvae, we did not detect any anomaly of body morphology. However, they showed an abnormal swimming pattern and disorganized midbrain, a higher center controlling movement. Our results suggest that HO-exposed fishes suffer developmental disorder of the brain that triggers an abnormal swimming behavior and that HO may be selectively toxic to the brain and cause physical disability throughout the life span of these fishes.

  7. Earth orbital teleoperator visual system evaluation program

    NASA Technical Reports Server (NTRS)

    Shields, N. L., Jr.; Kirkpatrick, M., III; Frederick, P. N.; Malone, T. B.

    1975-01-01

    Empirical tests of range estimation accuracy and resolution, via television, under monoptic and steroptic viewing conditions are discussed. Test data are used to derive man machine interface requirements and make design decisions for an orbital remote manipulator system. Remote manipulator system visual tasks are given and the effects of system parameters of these tasks are evaluated.

  8. Validation of the Preverbal Visual Assessment (PreViAs) questionnaire.

    PubMed

    García-Ormaechea, Inés; González, Inmaculada; Duplá, María; Andres, Eva; Pueyo, Victoria

    2014-10-01

    Visual cognitive integrative functions need to be evaluated by a behavioral assessment, which requires an experienced evaluator. The Preverbal Visual Assessment (PreViAs) questionnaire was designed to evaluate these functions, both in general pediatric population or in children with high risk of visual cognitive problems, through primary caregivers' answers. We aimed to validate the PreViAs questionnaire by comparing caregiver reports with results from a comprehensive clinical protocol. A total of 220 infants (<2 years old) were divided into two groups according to visual development, as determined by the clinical protocol. Their primary caregivers completed the PreViAs questionnaire, which consists of 30 questions related to one or more visual domains: visual attention, visual communication, visual-motor coordination, and visual processing. Questionnaire answers were compared with results of behavioral assessments performed by three pediatric ophthalmologists. Results of the clinical protocol classified 128 infants as having normal visual maturation, and 92 as having abnormal visual maturation. The specificity of PreViAs questionnaire was >80%, and sensitivity was 64%-79%. More than 80% of the infants were correctly classified, and test-retest reliability exceeded 0.9 for all domains. The PreViAs questionnaire is useful to detect abnormal visual maturation in infants from birth to 24months of age. It improves the anamnesis process in infants at risk of visual dysfunctions. Copyright © 2014. Published by Elsevier Ireland Ltd.

  9. Visually Guided Step Descent in Children with Williams Syndrome

    ERIC Educational Resources Information Center

    Cowie, Dorothy; Braddick, Oliver; Atkinson, Janette

    2012-01-01

    Individuals with Williams syndrome (WS) have impairments in visuospatial tasks and in manual visuomotor control, consistent with parietal and cerebellar abnormalities. Here we examined whether individuals with WS also have difficulties in visually controlling whole-body movements. We investigated visual control of stepping down at a change of…

  10. A hierarchical, retinotopic proto-organization of the primate visual system at birth

    PubMed Central

    Arcaro, Michael J; Livingstone, Margaret S

    2017-01-01

    The adult primate visual system comprises a series of hierarchically organized areas. Each cortical area contains a topographic map of visual space, with different areas extracting different kinds of information from the retinal input. Here we asked to what extent the newborn visual system resembles the adult organization. We find that hierarchical, topographic organization is present at birth and therefore constitutes a proto-organization for the entire primate visual system. Even within inferior temporal cortex, this proto-organization was already present, prior to the emergence of category selectivity (e.g., faces or scenes). We propose that this topographic organization provides the scaffolding for the subsequent development of visual cortex that commences at the onset of visual experience DOI: http://dx.doi.org/10.7554/eLife.26196.001 PMID:28671063

  11. Visualization-based decision support for value-driven system design

    NASA Astrophysics Data System (ADS)

    Tibor, Elliott

    In the past 50 years, the military, communication, and transportation systems that permeate our world, have grown exponentially in size and complexity. The development and production of these systems has seen ballooning costs and increased risk. This is particularly critical for the aerospace industry. The inability to deal with growing system complexity is a crippling force in the advancement of engineered systems. Value-Driven Design represents a paradigm shift in the field of design engineering that has potential to help counteract this trend. The philosophy of Value-Driven Design places the desires of the stakeholder at the forefront of the design process to capture true preferences and reveal system alternatives that were never previously thought possible. Modern aerospace engineering design problems are large, complex, and involve multiple levels of decision-making. To find the best design, the decision-maker is often required to analyze hundreds or thousands of combinations of design variables and attributes. Visualization can be used to support these decisions, by communicating large amounts of data in a meaningful way. Understanding the design space, the subsystem relationships, and the design uncertainties is vital to the advancement of Value-Driven Design as an accepted process for the development of more effective, efficient, robust, and elegant aerospace systems. This research investigates the use of multi-dimensional data visualization tools to support decision-making under uncertainty during the Value-Driven Design process. A satellite design system comprising a satellite, ground station, and launch vehicle is used to demonstrate effectiveness of new visualization methods to aid in decision support during complex aerospace system design. These methods are used to facilitate the exploration of the feasible design space by representing the value impact of system attribute changes and comparing the results of multi-objective optimization formulations

  12. M-Stream Deficits and Reading-Related Visual Processes in Developmental Dyslexia

    ERIC Educational Resources Information Center

    Boden, Catherine; Giaschi, Deborah

    2007-01-01

    Some visual processing deficits in developmental dyslexia have been attributed to abnormalities in the subcortical M stream and/or the cortical dorsal stream of the visual pathways. The nature of the relationship between these visual deficits and reading is unknown. The purpose of the present article was to characterize reading-related perceptual…

  13. Visual dysfunction in Parkinson’s disease

    PubMed Central

    Weil, Rimona S.; Schrag, Anette E.; Warren, Jason D.; Crutch, Sebastian J.; Lees, Andrew J.; Morris, Huw R.

    2016-01-01

    Patients with Parkinson’s disease have a number of specific visual disturbances. These include changes in colour vision and contrast sensitivity and difficulties with complex visual tasks such as mental rotation and emotion recognition. We review changes in visual function at each stage of visual processing from retinal deficits, including contrast sensitivity and colour vision deficits to higher cortical processing impairments such as object and motion processing and neglect. We consider changes in visual function in patients with common Parkinson’s disease-associated genetic mutations including GBA and LRRK2. We discuss the association between visual deficits and clinical features of Parkinson’s disease such as rapid eye movement sleep behavioural disorder and the postural instability and gait disorder phenotype. We review the link between abnormal visual function and visual hallucinations, considering current models for mechanisms of visual hallucinations. Finally, we discuss the role of visuo-perceptual testing as a biomarker of disease and predictor of dementia in Parkinson’s disease. PMID:27412389

  14. Visual color matching system based on RGB LED light source

    NASA Astrophysics Data System (ADS)

    Sun, Lei; Huang, Qingmei; Feng, Chen; Li, Wei; Wang, Chaofeng

    2018-01-01

    In order to study the property and performance of LED as RGB primary color light sources on color mixture in visual psychophysical experiments, and to find out the difference between LED light source and traditional light source, a visual color matching experiment system based on LED light sources as RGB primary colors has been built. By simulating traditional experiment of metameric color matching in CIE 1931 RGB color system, it can be used for visual color matching experiments to obtain a set of the spectral tristimulus values which we often call color-matching functions (CMFs). This system consists of three parts: a monochromatic light part using blazed grating, a light mixing part where the summation of 3 LED illuminations are to be visually matched with a monochromatic illumination, and a visual observation part. The three narrow band LEDs used have dominant wavelengths of 640 nm (red), 522 nm (green) and 458 nm (blue) respectively and their intensities can be controlled independently. After the calibration of wavelength and luminance of LED sources with a spectrophotometer, a series of visual color matching experiments have been carried out by 5 observers. The results are compared with those from CIE 1931 RGB color system, and have been used to compute an average locus for the spectral colors in the color triangle, with white at the center. It has been shown that the use of LED is feasible and has the advantages of easy control, good stability and low cost.

  15. Audio-Visual Perception System for a Humanoid Robotic Head

    PubMed Central

    Viciana-Abad, Raquel; Marfil, Rebeca; Perez-Lorenzo, Jose M.; Bandera, Juan P.; Romero-Garces, Adrian; Reche-Lopez, Pedro

    2014-01-01

    One of the main issues within the field of social robotics is to endow robots with the ability to direct attention to people with whom they are interacting. Different approaches follow bio-inspired mechanisms, merging audio and visual cues to localize a person using multiple sensors. However, most of these fusion mechanisms have been used in fixed systems, such as those used in video-conference rooms, and thus, they may incur difficulties when constrained to the sensors with which a robot can be equipped. Besides, within the scope of interactive autonomous robots, there is a lack in terms of evaluating the benefits of audio-visual attention mechanisms, compared to only audio or visual approaches, in real scenarios. Most of the tests conducted have been within controlled environments, at short distances and/or with off-line performance measurements. With the goal of demonstrating the benefit of fusing sensory information with a Bayes inference for interactive robotics, this paper presents a system for localizing a person by processing visual and audio data. Moreover, the performance of this system is evaluated and compared via considering the technical limitations of unimodal systems. The experiments show the promise of the proposed approach for the proactive detection and tracking of speakers in a human-robot interactive framework. PMID:24878593

  16. Simple Smartphone-Based Guiding System for Visually Impaired People

    PubMed Central

    Lin, Bor-Shing; Lee, Cheng-Che; Chiang, Pei-Ying

    2017-01-01

    Visually impaired people are often unaware of dangers in front of them, even in familiar environments. Furthermore, in unfamiliar environments, such people require guidance to reduce the risk of colliding with obstacles. This study proposes a simple smartphone-based guiding system for solving the navigation problems for visually impaired people and achieving obstacle avoidance to enable visually impaired people to travel smoothly from a beginning point to a destination with greater awareness of their surroundings. In this study, a computer image recognition system and smartphone application were integrated to form a simple assisted guiding system. Two operating modes, online mode and offline mode, can be chosen depending on network availability. When the system begins to operate, the smartphone captures the scene in front of the user and sends the captured images to the backend server to be processed. The backend server uses the faster region convolutional neural network algorithm or the you only look once algorithm to recognize multiple obstacles in every image, and it subsequently sends the results back to the smartphone. The results of obstacle recognition in this study reached 60%, which is sufficient for assisting visually impaired people in realizing the types and locations of obstacles around them. PMID:28608811

  17. Simple Smartphone-Based Guiding System for Visually Impaired People.

    PubMed

    Lin, Bor-Shing; Lee, Cheng-Che; Chiang, Pei-Ying

    2017-06-13

    Visually impaired people are often unaware of dangers in front of them, even in familiar environments. Furthermore, in unfamiliar environments, such people require guidance to reduce the risk of colliding with obstacles. This study proposes a simple smartphone-based guiding system for solving the navigation problems for visually impaired people and achieving obstacle avoidance to enable visually impaired people to travel smoothly from a beginning point to a destination with greater awareness of their surroundings. In this study, a computer image recognition system and smartphone application were integrated to form a simple assisted guiding system. Two operating modes, online mode and offline mode, can be chosen depending on network availability. When the system begins to operate, the smartphone captures the scene in front of the user and sends the captured images to the backend server to be processed. The backend server uses the faster region convolutional neural network algorithm or the you only look once algorithm to recognize multiple obstacles in every image, and it subsequently sends the results back to the smartphone. The results of obstacle recognition in this study reached 60%, which is sufficient for assisting visually impaired people in realizing the types and locations of obstacles around them.

  18. Aberrant Hyperconnectivity in the Motor System at Rest Is Linked to Motor Abnormalities in Schizophrenia Spectrum Disorders.

    PubMed

    Walther, Sebastian; Stegmayer, Katharina; Federspiel, Andrea; Bohlhalter, Stephan; Wiest, Roland; Viher, Petra V

    2017-09-01

    Motor abnormalities are frequently observed in schizophrenia and structural alterations of the motor system have been reported. The association of aberrant motor network function, however, has not been tested. We hypothesized that abnormal functional connectivity would be related to the degree of motor abnormalities in schizophrenia. In 90 subjects (46 patients) we obtained resting stated functional magnetic resonance imaging (fMRI) for 8 minutes 40 seconds at 3T. Participants further completed a motor battery on the scanning day. Regions of interest (ROI) were cortical motor areas, basal ganglia, thalamus and motor cerebellum. We computed ROI-to-ROI functional connectivity. Principal component analyses of motor behavioral data produced 4 factors (primary motor, catatonia and dyskinesia, coordination, and spontaneous motor activity). Motor factors were correlated with connectivity values. Schizophrenia was characterized by hyperconnectivity in 3 main areas: motor cortices to thalamus, motor cortices to cerebellum, and prefrontal cortex to the subthalamic nucleus. In patients, thalamocortical hyperconnectivity was linked to catatonia and dyskinesia, whereas aberrant connectivity between rostral anterior cingulate and caudate was linked to the primary motor factor. Likewise, connectivity between motor cortex and cerebellum correlated with spontaneous motor activity. Therefore, altered functional connectivity suggests a specific intrinsic and tonic neural abnormality in the motor system in schizophrenia. Furthermore, altered neural activity at rest was linked to motor abnormalities on the behavioral level. Thus, aberrant resting state connectivity may indicate a system out of balance, which produces characteristic behavioral alterations. © The Author 2017. Published by Oxford University Press on behalf of the Maryland Psychiatric Research Center. All rights reserved. For permissions, please email: journals.permissions@oup.com.

  19. Lightness computation by the human visual system

    NASA Astrophysics Data System (ADS)

    Rudd, Michael E.

    2017-05-01

    A model of achromatic color computation by the human visual system is presented, which is shown to account in an exact quantitative way for a large body of appearance matching data collected with simple visual displays. The model equations are closely related to those of the original Retinex model of Land and McCann. However, the present model differs in important ways from Land and McCann's theory in that it invokes additional biological and perceptual mechanisms, including contrast gain control, different inherent neural gains for incremental, and decremental luminance steps, and two types of top-down influence on the perceptual weights applied to local luminance steps in the display: edge classification and spatial integration attentional windowing. Arguments are presented to support the claim that these various visual processes must be instantiated by a particular underlying neural architecture. By pointing to correspondences between the architecture of the model and findings from visual neurophysiology, this paper suggests that edge classification involves a top-down gating of neural edge responses in early visual cortex (cortical areas V1 and/or V2) while spatial integration windowing occurs in cortical area V4 or beyond.

  20. Postural abnormalities and contraversive pushing following right hemisphere brain damage.

    PubMed

    Lafosse, C; Kerckhofs, E; Vereeck, L; Troch, M; Van Hoydonck, G; Moeremans, M; Sneyers, C; Broeckx, J; Dereymaeker, L

    2007-06-01

    We investigated the presence of postural abnormalities in a consecutive sample of stroke patients, with either left or right brain damage, in relation to their perceived body position in space. The presence or absence of posture-related symptoms was judged by two trained therapists and subsequently analysed by hierarchical classes analysis (HICLAS). The subject classes resulting from the HICLAS model were further validated with respect to posture-related measurements, such as centre of gravity position and head position, as well as measurements related to the postural body scheme, such as the perception of postural and visual verticality. The results of the classification analysis clearly demonstrated a relation between the presence of right brain damage and abnormalities in body geometry. The HICLAS model revealed three classes of subjects: The first class contained almost all the patients without neglect and without any signs of contraversive pushing. They were mainly characterised by a normal body axis in any position. The second class were all neglect patients but predominantly without any contraversive pushing. The third class contained right brain damaged patients, all showing neglect and mostly exhibiting contraversive pushing. The patients in the third class showed a clear resistance to bringing the weight over to the ipsilesional side when the therapist attempted to make the subject achieve a vertical posture across the midline. The clear correspondence between abnormalities of the observed body geometry and the tilt of the subjective postural and visual vertical suggests that a patient's postural body geometry is characterised by leaning towards the side of space where he/she feels aligned with an altered postural body scheme. The presence of contraversive pushing after right brain damage points in to a spatial higher-order processing deficit underlying the higher frequency and severity of the axial postural abnormalities found after right brain lesions.

  1. ATS displays: A reasoning visualization tool for expert systems

    NASA Technical Reports Server (NTRS)

    Selig, William John; Johannes, James D.

    1990-01-01

    Reasoning visualization is a useful tool that can help users better understand the inherently non-sequential logic of an expert system. While this is desirable in most all expert system applications, it is especially so for such critical systems as those destined for space-based operations. A hierarchical view of the expert system reasoning process and some characteristics of these various levels is presented. Also presented are Abstract Time Slice (ATS) displays, a tool to visualize the plethora of interrelated information available at the host inferencing language level of reasoning. The usefulness of this tool is illustrated with some examples from a prototype potable water expert system for possible use aboard Space Station Freedom.

  2. The Orbital Maneuvering Vehicle Training Facility visual system concept

    NASA Technical Reports Server (NTRS)

    Williams, Keith

    1989-01-01

    The purpose of the Orbital Maneuvering Vehicle (OMV) Training Facility (OTF) is to provide effective training for OMV pilots. A critical part of the training environment is the Visual System, which will simulate the video scenes produced by the OMV Closed-Circuit Television (CCTV) system. The simulation will include camera models, dynamic target models, moving appendages, and scene degradation due to the compression/decompression of video signal. Video system malfunctions will also be provided to ensure that the pilot is ready to meet all challenges the real-world might provide. One possible visual system configuration for the training facility that will meet existing requirements is described.

  3. CLFs-based optimization control for a class of constrained visual servoing systems.

    PubMed

    Song, Xiulan; Miaomiao, Fu

    2017-03-01

    In this paper, we use the control Lyapunov function (CLF) technique to present an optimized visual servo control method for constrained eye-in-hand robot visual servoing systems. With the knowledge of camera intrinsic parameters and depth of target changes, visual servo control laws (i.e. translation speed) with adjustable parameters are derived by image point features and some known CLF of the visual servoing system. The Fibonacci method is employed to online compute the optimal value of those adjustable parameters, which yields an optimized control law to satisfy constraints of the visual servoing system. The Lyapunov's theorem and the properties of CLF are used to establish stability of the constrained visual servoing system in the closed-loop with the optimized control law. One merit of the presented method is that there is no requirement of online calculating the pseudo-inverse of the image Jacobian's matrix and the homography matrix. Simulation and experimental results illustrated the effectiveness of the method proposed here. Copyright © 2016 ISA. Published by Elsevier Ltd. All rights reserved.

  4. Visual impairment in FOXG1-mutated individuals and mice.

    PubMed

    Boggio, E M; Pancrazi, L; Gennaro, M; Lo Rizzo, C; Mari, F; Meloni, I; Ariani, F; Panighini, A; Novelli, E; Biagioni, M; Strettoi, E; Hayek, J; Rufa, A; Pizzorusso, T; Renieri, A; Costa, M

    2016-06-02

    The Forkead Box G1 (FOXG1 in humans, Foxg1 in mice) gene encodes for a DNA-binding transcription factor, essential for the development of the telencephalon in mammalian forebrain. Mutations in FOXG1 have been reported to be involved in the onset of Rett Syndrome, for which sequence alterations of MECP2 and CDKL5 are known. While visual alterations are not classical hallmarks of Rett syndrome, an increasing body of evidence shows visual impairment in patients and in MeCP2 and CDKL5 animal models. Herein we focused on the functional role of FOXG1 in the visual system of animal models (Foxg1(+/Cre) mice) and of a cohort of subjects carrying FOXG1 mutations or deletions. Visual physiology of Foxg1(+/Cre) mice was assessed by visually evoked potentials, which revealed a significant reduction in response amplitude and visual acuity with respect to wild-type littermates. Morphological investigation showed abnormalities in the organization of excitatory/inhibitory circuits in the visual cortex. No alterations were observed in retinal structure. By examining a cohort of FOXG1-mutated individuals with a panel of neuro-ophthalmological assessments, we found that all of them exhibited visual alterations compatible with high-level visual dysfunctions. In conclusion our data show that Foxg1 haploinsufficiency results in an impairment of mouse and human visual cortical function. Copyright © 2016 IBRO. Published by Elsevier Ltd. All rights reserved.

  5. Cognitive processing of visual images in migraine populations in between headache attacks.

    PubMed

    Mickleborough, Marla J S; Chapman, Christine M; Toma, Andreea S; Handy, Todd C

    2014-09-25

    People with migraine headache have altered interictal visual sensory-level processing in between headache attacks. Here we examined the extent to which these migraine abnormalities may extend into higher visual processing such as implicit evaluative analysis of visual images in between migraine events. Specifically, we asked two groups of participants--migraineurs (N=29) and non-migraine controls (N=29)--to view a set of unfamiliar commercial logos in the context of a target identification task as the brain electrical responses to these objects were recorded via event-related potentials (ERPs). Following this task, participants individually identified those logos that they most liked or disliked. We applied a between-groups comparison of how ERP responses to logos varied as a function of hedonic evaluation. Our results suggest migraineurs have abnormal implicit evaluative processing of visual stimuli. Specifically, migraineurs lacked a bias for disliked logos found in control subjects, as measured via a late positive potential (LPP) ERP component. These results suggest post-sensory consequences of migraine in between headache events, specifically abnormal cognitive evaluative processing with a lack of normal categorical hedonic evaluation. Copyright © 2014 Elsevier B.V. All rights reserved.

  6. Earth orbital teleoperator visual system evaluation program

    NASA Technical Reports Server (NTRS)

    Frederick, P. N.; Shields, N. L., Jr.; Kirkpatrick, M., III

    1977-01-01

    Visual system parameters and stereoptic television component geometries were evaluated for optimum viewing. The accuracy of operator range estimation using a Fresnell stereo television system with a three dimensional cursor was examined. An operator's ability to align three dimensional targets using vidicon tube and solid state television cameras as part of a Fresnell stereoptic system was evaluated. An operator's ability to discriminate between varied color samples viewed with a color television system was determined.

  7. Stimulation from Cochlear Implant Electrodes Assists with Recovery from Asymmetric Perceptual Tilt: Evidence from the Subjective Visual Vertical Test

    PubMed Central

    Gnanasegaram, Joshua J.; Parkes, William J.; Cushing, Sharon L.; McKnight, Carmen L.; Papsin, Blake C.; Gordon, Karen A.

    2016-01-01

    Vestibular end organ impairment is highly prevalent in children who have sensorineural hearing loss (SNHL) rehabilitated with cochlear implants (CIs). As a result, spatial perception is likely to be impacted in this population. Of particular interest is the perception of visual vertical because it reflects a perceptual tilt in the roll axis and is sensitive to an imbalance in otolith function. The objectives of the present study were thus to identify abnormalities in perception of the vertical plane in children with SNHL and determine whether such abnormalities could be resolved with stimulation from the CI. Participants included 53 children (15.2 ± 4.0 years of age) with SNHL and vestibular loss, confirmed with vestibular evoked myogenic potential (VEMP) testing. Testing protocol was validated in a sample of nine young adults with normal hearing (28.8 ± 7.7 years). Perception of visual vertical was assessed using the static Subjective Visual Vertical (SVV) test performed with and without stimulation in the participants with cochleovestibular loss. Trains of electrical pulses were delivered by an electrode in the left and/or right ear. Asymmetric spatial orientation deficits were found in nearly half of the participants with CIs (24/53 [45%]). The abnormal perception in this cohort was exacerbated by visual tilts in the direction of their deficit. Electric pulse trains delivered using the CI shifted this abnormal perception towards center (i.e., normal; p = 0.007). Importantly, this benefit was realized regardless of which ear was stimulated. These results suggest a role for CI stimulation beyond the auditory system, in particular, for improving vestibular/balance function. PMID:27679562

  8. Altered Functional Connectivity of the Primary Visual Cortex in Subjects with Amblyopia

    PubMed Central

    Ding, Kun; Liu, Yong; Yan, Xiaohe; Lin, Xiaoming; Jiang, Tianzi

    2013-01-01

    Amblyopia, which usually occurs during early childhood and results in poor or blurred vision, is a disorder of the visual system that is characterized by a deficiency in an otherwise physically normal eye or by a deficiency that is out of proportion with the structural or functional abnormalities of the eye. Our previous study demonstrated alterations in the spontaneous activity patterns of some brain regions in individuals with anisometropic amblyopia compared to subjects with normal vision. To date, it remains unknown whether patients with amblyopia show characteristic alterations in the functional connectivity patterns in the visual areas of the brain, particularly the primary visual area. In the present study, we investigated the differences in the functional connectivity of the primary visual area between individuals with amblyopia and normal-sighted subjects using resting functional magnetic resonance imaging. Our findings demonstrated that the cerebellum and the inferior parietal lobule showed altered functional connectivity with the primary visual area in individuals with amblyopia, and this finding provides further evidence for the disruption of the dorsal visual pathway in amblyopic subjects. PMID:23844297

  9. Visual prosthesis wireless energy transfer system optimal modeling

    PubMed Central

    2014-01-01

    Background Wireless energy transfer system is an effective way to solve the visual prosthesis energy supply problems, theoretical modeling of the system is the prerequisite to do optimal energy transfer system design. Methods On the basis of the ideal model of the wireless energy transfer system, according to visual prosthesis application condition, the system modeling is optimized. During the optimal modeling, taking planar spiral coils as the coupling devices between energy transmitter and receiver, the effect of the parasitic capacitance of the transfer coil is considered, and especially the concept of biological capacitance is proposed to consider the influence of biological tissue on the energy transfer efficiency, resulting in the optimal modeling’s more accuracy for the actual application. Results The simulation data of the optimal model in this paper is compared with that of the previous ideal model, the results show that under high frequency condition, the parasitic capacitance of inductance and biological capacitance considered in the optimal model could have great impact on the wireless energy transfer system. The further comparison with the experimental data verifies the validity and accuracy of the optimal model proposed in this paper. Conclusions The optimal model proposed in this paper has a higher theoretical guiding significance for the wireless energy transfer system’s further research, and provide a more precise model reference for solving the power supply problem in visual prosthesis clinical application. PMID:24428906

  10. Influence of rotating shift work on visual reaction time and visual evoked potential.

    PubMed

    R V, Hemamalini; N, Krishnamurthy; A, Saravanan

    2014-10-01

    The present day life style is changing the circadian rhythm of the body especially in rotating night shift workers. The impact of this prolongs their reaction time. Night shift also interferes with the circadian variation of pupil size which may affect the visual evoked potential. To compare the visual reaction time, visual evoked potential (VEP) in rotating night shift workers & day workers and also to correlate the changes in visual reaction time with visual evoked potential. Forty healthy male security guards & staff (25 - 35 y) who did rotating night shifts at least for six months & 40 d workers (25 - 35 y) who did not do night shift in last two years were involved in the study. Visual reaction time and the latency & amplitude of VEP were recorded. Kolmogorov- Smirnov test for normalcy showed the latencies & amplitude of VEP to be normally distributed. Student's unpaired t test showed significant difference (p<0.05) in the visual time and in the latencies of VEP between night shift & day workers. There was no significant difference in the amplitude of VEP. Night shift workers who are prone to circadian rhythm alteration will have prolonged visual reaction time & visual evoked potential abnormalities. Implementation of Bright Light Therapy would be beneficial to the night shift worker.

  11. Spreading Photoparoxysmal EEG Response is Associated with an Abnormal Cortical Excitability Pattern

    ERIC Educational Resources Information Center

    Siniatchkin, Michael; Groppa, Sergey; Jerosch, Bettina; Muhle, Hiltrud; Kurth, Christoph; Shepherd, Alex J.; Siebner, Hartwig; Stephani, Ulrich

    2007-01-01

    Photosensitivity or photoparoxysmal response (PPR) is a highly heritable electroencephalographic trait characterized by an abnormal cortical response to intermittent photic stimulation (IPS). In PPR-positive individuals, IPS induces spikes, spike-waves or intermittent slow waves. The PPR may be restricted to posterior visual areas (i.e. local PPR…

  12. Global abnormalities in lymphatic function following systemic therapy in patients with breast cancer.

    PubMed

    Bains, S K; Peters, A M; Zammit, C; Ryan, N; Ballinger, J; Glass, D M; Allen, S; Stanton, A W B; Mortimer, P S; Purushotham, A D

    2015-04-01

    Breast cancer-related lymphoedema (BCRL) is a result of interaction between several pathophysiological processes, and is not simply a 'stopcock' effect resulting from removal of axillary lymph nodes. The aim of this study was to test the hypothesis that there is a constitutional 'global' lymphatic dysfunction in patients who develop BCRL. Lower-limb lymphoscintigraphy was performed in 30 women who had undergone axillary lymph node dissection at least 3 years previously, of whom 15 had BCRL and 15 did not. No patient had any clinical abnormality of the lower limb. The control group comprised 24 women with no history of cancer or lower-limb lymphoedema. (99m) Tc-Nanocoll was injected subcutaneously into the first webspace of each foot, followed by whole-body imaging. Scans were reported as abnormal if there was delay in lymph transport or rerouting through skin or deep system. Quantification was expressed as the percentage injected activity accumulating in ilioinguinal nodes. Mean(s.d.) ilioinguinal nodal accumulation at 150 min was significantly lower in women with BCRL than in those without (2·7(2·5) versus 5·9(4·8) per cent respectively; P = 0·006). Abnormal findings on lower-limb lymphoscintigraphy were observed in 17 of the 30 patients: ten of the 15 women who had BCRL and seven of the 15 who did not. None of the 24 control subjects had abnormal scan findings. Women with BCRL had reduced lower-limb lymph drainage, supporting the hypothesis of a predisposition to BCRL. A surprisingly high proportion of patients with breast cancer also demonstrated lymphatic dysfunction, despite clinically normal lower limbs. Possible explanations could be a systemic effect of breast cancer or its treatment, or an unidentified association between breast cancer and lymphatic dysfunction. ISRCTN84866416 ( http://www.isrctn.com). © 2015 BJS Society Ltd Published by John Wiley & Sons Ltd.

  13. Windows into the Visual Brain: New Discoveries about the Visual System, Its Functions, and Implications for Practitioners

    ERIC Educational Resources Information Center

    Jan, James E.; Heaven, Roberta K. B.; Matsuba, Carey; Langley, M. Beth; Roman-Lantzy, Christine; Anthony, Tanni L

    2013-01-01

    Introduction: In recent years, major progress has been made in understanding the human visual system because of new investigative techniques. These developments often contradict older concepts about visual function. Methods: A detailed literature search and interprofessional discussions. Results: Recent innovative neurological tests are described…

  14. Levetiracetam reduces abnormal network activations in temporal lobe epilepsy.

    PubMed

    Wandschneider, Britta; Stretton, Jason; Sidhu, Meneka; Centeno, Maria; Kozák, Lajos R; Symms, Mark; Thompson, Pamela J; Duncan, John S; Koepp, Matthias J

    2014-10-21

    We used functional MRI (fMRI) and a left-lateralizing verbal and a right-lateralizing visual-spatial working memory (WM) paradigm to investigate the effects of levetiracetam (LEV) on cognitive network activations in patients with drug-resistant temporal lobe epilepsy (TLE). In a retrospective study, we compared task-related fMRI activations and deactivations in 53 patients with left and 54 patients with right TLE treated with (59) or without (48) LEV. In patients on LEV, activation patterns were correlated with the daily LEV dose. We isolated task- and syndrome-specific effects. Patients on LEV showed normalization of functional network deactivations in the right temporal lobe in right TLE during the right-lateralizing visual-spatial task and in the left temporal lobe in left TLE during the verbal task. In a post hoc analysis, a significant dose-dependent effect was demonstrated in right TLE during the visual-spatial WM task: the lower the LEV dose, the greater the abnormal right hippocampal activation. At a less stringent threshold (p < 0.05, uncorrected for multiple comparisons), a similar dose effect was observed in left TLE during the verbal task: both hippocampi were more abnormally activated in patients with lower doses, but more prominently on the left. Our findings suggest that LEV is associated with restoration of normal activation patterns. Longitudinal studies are necessary to establish whether the neural patterns translate to drug response. This study provides Class III evidence that in patients with drug-resistant TLE, levetiracetam has a dose-dependent facilitation of deactivation of mesial temporal structures. © 2014 American Academy of Neurology.

  15. Visual information processing of faces in body dysmorphic disorder.

    PubMed

    Feusner, Jamie D; Townsend, Jennifer; Bystritsky, Alexander; Bookheimer, Susan

    2007-12-01

    Body dysmorphic disorder (BDD) is a severe psychiatric condition in which individuals are preoccupied with perceived appearance defects. Clinical observation suggests that patients with BDD focus on details of their appearance at the expense of configural elements. This study examines abnormalities in visual information processing in BDD that may underlie clinical symptoms. To determine whether patients with BDD have abnormal patterns of brain activation when visually processing others' faces with high, low, or normal spatial frequency information. Case-control study. University hospital. Twelve right-handed, medication-free subjects with BDD and 13 control subjects matched by age, sex, and educational achievement. Intervention Functional magnetic resonance imaging while performing matching tasks of face stimuli. Stimuli were neutral-expression photographs of others' faces that were unaltered, altered to include only high spatial frequency visual information, or altered to include only low spatial frequency visual information. Blood oxygen level-dependent functional magnetic resonance imaging signal changes in the BDD and control groups during tasks with each stimulus type. Subjects with BDD showed greater left hemisphere activity relative to controls, particularly in lateral prefrontal cortex and lateral temporal lobe regions for all face tasks (and dorsal anterior cingulate activity for the low spatial frequency task). Controls recruited left-sided prefrontal and dorsal anterior cingulate activity only for the high spatial frequency task. Subjects with BDD demonstrate fundamental differences from controls in visually processing others' faces. The predominance of left-sided activity for low spatial frequency and normal faces suggests detail encoding and analysis rather than holistic processing, a pattern evident in controls only for high spatial frequency faces. These abnormalities may be associated with apparent perceptual distortions in patients with BDD. The

  16. Visual functions of commercial drivers in relation to road accidents in Nigeria

    PubMed Central

    Oladehinde, M. K.; Adeoye, A. O.; Adegbehingbe, B. O.; Onakoya, A. O.

    2007-01-01

    Objective: To determine the effects of the visual functions on the occurrence of road traffic accidents (RTA) amongst commercial drivers in Ife central local government area (LGA) of Osun state of Nigeria. Design: A cross-sectional study. Settings: Four major motor parks located at Ife Central LGA. Materials and Methods: Of the estimated 270 commercial drivers in the four major parks of the LGA, 215 consecutive drivers were interviewed and had their eyes examined. Structured questionnaires were administered by an ophthalmologist. Results: The prevalence of visual impairment (visual acuity < 6/18) in the better eye without correction was 3.3% ± 2.4 and there was a significant association between uncorrected visual acuity impairment in the better eye and RTA (P = 0.0152). Refractive error was seen in 8.4% of the drivers, but none of these wear corrective glasses. Visual field defect, abnormal stereopsis and color vision impairment did not have any significant association with RTA. Conclusion: Poor visual acuity is strongly associated with RTA amongst Nigerian commercial drivers as opposed to visual field defect, abnormal color vision and stereopsis. A significant proportion of visual impairment was due to uncorrected refractive errors. PMID:21938219

  17. Surprising characteristics of visual systems of invertebrates.

    PubMed

    González-Martín-Moro, J; Hernández-Verdejo, J L; Jiménez-Gahete, A E

    2017-01-01

    To communicate relevant and striking aspects about the visual system of some close invertebrates. Review of the related literature. The capacity of snails to regenerate a complete eye, the benefit of the oval shape of the compound eye of many flying insects as a way of stabilising the image during flight, the potential advantages related to the extreme refractive error that characterises the ocelli of many insects, as well as the ability to detect polarised light as a navigation system, are some of the surprising capabilities present in the small invertebrate eyes that are described in this work. The invertebrate eyes have capabilities and sensorial modalities that are not present in the human eye. The study of the eyes of these animals can help us to improve our understanding of our visual system, and inspire the development of optical devices. Copyright © 2016 Sociedad Española de Oftalmología. Publicado por Elsevier España, S.L.U. All rights reserved.

  18. Early screening of an infant's visual system

    NASA Astrophysics Data System (ADS)

    Costa, Manuel F. M.; Jorge, Jorge M.

    1999-06-01

    It is of utmost importance to the development of the child's visual system that she perceives clear focused retinal images. Furthermore if the refractive problems are not corrected in due time amblyopia may occur--myopia and hyperopia can only cause important problems in the future when they are significantly large, however for the astigmatism (rather frequent in infants) and anisometropia the problems tend to be more stringent. The early evaluation of the visual status of human infants is thus of critical importance. Photorefraction is a convenient technique for this kind of subjects. Essentially a light beam is delivered into the eyes. It is refracted by the ocular media, strikes the retina, focusing or not, reflects off and is collected by a camera. The photorefraction setup we established using new technological breakthroughs on the fields of imaging devices, digital image processing and fiber optics, allows a fast noninvasive evaluation of children visual status (refractive errors, accommodation, strabismus, ...). Results of the visual screening of a group of risk' child descents of blinds or amblyopes will be presented.

  19. FMRI of visual working memory in high school football players.

    PubMed

    Shenk, Trey E; Robinson, Meghan E; Svaldi, Diana O; Abbas, Kausar; Breedlove, Katherine M; Leverenz, Larry J; Nauman, Eric A; Talavage, Thomas M

    2015-01-01

    Visual working memory deficits have been observed in at-risk athletes. This study uses a visual N-back working memory functional magnetic resonance imaging task to longitudinally assess asymptomatic football athletes for abnormal activity. Athletes were increasingly "flagged" as the season progressed. Flagging may provide early detection of injury.

  20. Advancements to Visualization Control System (VCS, part of UV-CDAT), a Visualization Package Designed for Climate Scientists

    NASA Astrophysics Data System (ADS)

    Lipsa, D.; Chaudhary, A.; Williams, D. N.; Doutriaux, C.; Jhaveri, S.

    2017-12-01

    Climate Data Analysis Tools (UV-CDAT, https://uvcdat.llnl.gov) is a data analysis and visualization software package developed at Lawrence Livermore National Laboratory and designed for climate scientists. Core components of UV-CDAT include: 1) Community Data Management System (CDMS) which provides I/O support and a data model for climate data;2) CDAT Utilities (GenUtil) that processes data using spatial and temporal averaging and statistic functions; and 3) Visualization Control System (VCS) for interactive visualization of the data. VCS is a Python visualization package primarily built for climate scientists, however, because of its generality and breadth of functionality, it can be a useful tool to other scientific applications. VCS provides 1D, 2D and 3D visualization functions such as scatter plot and line graphs for 1d data, boxfill, meshfill, isofill, isoline for 2d scalar data, vector glyphs and streamlines for 2d vector data and 3d_scalar and 3d_vector for 3d data. Specifically for climate data our plotting routines include projections, Skew-T plots and Taylor diagrams. While VCS provided a user-friendly API, the previous implementation of VCS relied on slow performing vector graphics (Cairo) backend which is suitable for smaller dataset and non-interactive graphics. LLNL and Kitware team has added a new backend to VCS that uses the Visualization Toolkit (VTK) as its visualization backend. VTK is one of the most popular open source, multi-platform scientific visualization library written in C++. Its use of OpenGL and pipeline processing architecture results in a high performant VCS library. Its multitude of available data formats and visualization algorithms results in easy adoption of new visualization methods and new data formats in VCS. In this presentation, we describe recent contributions to VCS that includes new visualization plots, continuous integration testing using Conda and CircleCI, tutorials and examples using Jupyter notebooks as well as

  1. Abnormal parietal encephalomalacia associated with schizophrenia: A case report.

    PubMed

    Pan, Fen; Wang, Jun-Yuan; Xu, Yi; Huang, Man-Li

    2017-03-01

    It is widely believed that structural abnormalities of the brain contribute to the pathophysiology of schizophrenia. The parietal lobe is a central hub of multisensory integration, and abnormities in this region might account for the clinical features of schizophrenia. However, few cases of parietal encephalomalacia associated with schizophrenia have been described. In this paper, we present a case of a 25-year-old schizophrenia patient with abnormal parietal encephalomalacia. The patient had poor nutrition and frequently had upper respiratory infections during childhood and adolescence. She showed severe schizophrenic symptoms such as visual hallucinations for 2 years. After examining all her possible medical conditions, we found that the patient had a lesion consistent with the diagnosis of encephalomalacia in her right parietal lobe and slight brain atrophy. The patient was prescribed olanzapine (10 mg per day). Her symptoms significantly improved after antipsychotic treatment and were still well controlled 1 year later. This case suggested that parietal encephalomalacia, which might be caused by inflammatory and infectious conditions in early life and be aggravated by undernutrition, might be implicated in the etiology of schizophrenia.

  2. [Acute visual loss in pregnancy caused by craniopharyngioma].

    PubMed

    Grillo-Mallo, E; Jiménez-Benito, J; Diéz-Feijóo, E; Alonso Alonso, I; Ferrero Collado, A; Muñoz Quiñones, S

    2014-04-01

    A 38-year-old female, at 20-weeks gestation, experienced a sudden visual loss and visual-field abnormalities. The neuroimaging tests showed a craniopharyngioma. Surgical removal was performed with a successful outcome as regards the pregnancy and visual function. It is known that pituitary adenomas may grow during pregnancy; however this is unusual in craniopharyngiomas. They usually present with visual problems due to their suprasellar topography. Surgery is the treatment of choice, the outcome essentially depending on its complete resection. Copyright © 2010 Sociedad Española de Oftalmología. Published by Elsevier Espana. All rights reserved.

  3. Intact anger recognition in depression despite aberrant visual facial information usage.

    PubMed

    Clark, Cameron M; Chiu, Carina G; Diaz, Ruth L; Goghari, Vina M

    2014-08-01

    Previous literature has indicated abnormalities in facial emotion recognition abilities, as well as deficits in basic visual processes in major depression. However, the literature is unclear on a number of important factors including whether or not these abnormalities represent deficient or enhanced emotion recognition abilities compared to control populations, and the degree to which basic visual deficits might impact this process. The present study investigated emotion recognition abilities for angry versus neutral facial expressions in a sample of undergraduate students with Beck Depression Inventory-II (BDI-II) scores indicative of moderate depression (i.e., ≥20), compared to matched low-BDI-II score (i.e., ≤2) controls via the Bubbles Facial Emotion Perception Task. Results indicated unimpaired behavioural performance in discriminating angry from neutral expressions in the high depressive symptoms group relative to the minimal depressive symptoms group, despite evidence of an abnormal pattern of visual facial information usage. The generalizability of the current findings is limited by the highly structured nature of the facial emotion recognition task used, as well as the use of an analog sample undergraduates scoring high in self-rated symptoms of depression rather than a clinical sample. Our findings suggest that basic visual processes are involved in emotion recognition abnormalities in depression, demonstrating consistency with the emotion recognition literature in other psychopathologies (e.g., schizophrenia, autism, social anxiety). Future research should seek to replicate these findings in clinical populations with major depression, and assess the association between aberrant face gaze behaviours and symptom severity and social functioning. Copyright © 2014 Elsevier B.V. All rights reserved.

  4. Soldier-worn augmented reality system for tactical icon visualization

    NASA Astrophysics Data System (ADS)

    Roberts, David; Menozzi, Alberico; Clipp, Brian; Russler, Patrick; Cook, James; Karl, Robert; Wenger, Eric; Church, William; Mauger, Jennifer; Volpe, Chris; Argenta, Chris; Wille, Mark; Snarski, Stephen; Sherrill, Todd; Lupo, Jasper; Hobson, Ross; Frahm, Jan-Michael; Heinly, Jared

    2012-06-01

    This paper describes the development and demonstration of a soldier-worn augmented reality system testbed that provides intuitive 'heads-up' visualization of tactically-relevant geo-registered icons. Our system combines a robust soldier pose estimation capability with a helmet mounted see-through display to accurately overlay geo-registered iconography (i.e., navigation waypoints, blue forces, aircraft) on the soldier's view of reality. Applied Research Associates (ARA), in partnership with BAE Systems and the University of North Carolina - Chapel Hill (UNC-CH), has developed this testbed system in Phase 2 of the DARPA ULTRA-Vis (Urban Leader Tactical, Response, Awareness, and Visualization) program. The ULTRA-Vis testbed system functions in unprepared outdoor environments and is robust to numerous magnetic disturbances. We achieve accurate and robust pose estimation through fusion of inertial, magnetic, GPS, and computer vision data acquired from helmet kit sensors. Icons are rendered on a high-brightness, 40°×30° field of view see-through display. The system incorporates an information management engine to convert CoT (Cursor-on-Target) external data feeds into mil-standard icons for visualization. The user interface provides intuitive information display to support soldier navigation and situational awareness of mission-critical tactical information.

  5. Imaging anatomy of the vestibular and visual systems.

    PubMed

    Gunny, Roxana; Yousry, Tarek A

    2007-02-01

    This review will outline the imaging anatomy of the vestibular and visual pathways, using computed tomography and magnetic resonance imaging, with emphasis on the more recent developments in neuroimaging. Technical advances in computed tomography and magnetic resonance imaging, such as the advent of multislice computed tomography and newer magnetic resonance imaging techniques such as T2-weighted magnetic resonance cisternography, have improved the imaging of the vestibular and visual pathways, allowing better visualization of the end organs and peripheral nerves. Higher field strength magnetic resonance imaging is a promising tool, which has been used to evaluate and resolve fine anatomic detail in vitro, as in the labyrinth. Advanced magnetic resonance imaging techniques such as functional magnetic resonance imaging and diffusion tractography have been used to identify cortical areas of activation and associated white matter pathways, and show potential for the future identification of complex neuronal relays involved in integrating these pathways. The assessment of the various components of the vestibular and the visual systems has improved with more detailed research on the imaging anatomy of these systems, the advent of high field magnetic resonance scanners and multislice computerized tomography, and the wider use of specific techniques such as tractography which displays white matter tracts not directly accessible until now.

  6. New apparatus of single particle trap system for aerosol visualization

    NASA Astrophysics Data System (ADS)

    Higashi, Hidenori; Fujioka, Tomomi; Endo, Tetsuo; Kitayama, Chiho; Seto, Takafumi; Otani, Yoshio

    2014-08-01

    Control of transport and deposition of charged aerosol particles is important in various manufacturing processes. Aerosol visualization is an effective method to directly observe light scattering signal from laser-irradiated single aerosol particle trapped in a visualization cell. New single particle trap system triggered by light scattering pulse signal was developed in this study. The performance of the device was evaluated experimentally. Experimental setup consisted of an aerosol generator, a differential mobility analyzer (DMA), an optical particle counter (OPC) and the single particle trap system. Polystylene latex standard (PSL) particles (0.5, 1.0 and 2.0 μm) were generated and classified according to the charge by the DMA. Singly charged 0.5 and 1.0 μm particles and doubly charged 2.0 μm particles were used as test particles. The single particle trap system was composed of a light scattering signal detector and a visualization cell. When the particle passed through the detector, trigger signal with a given delay time sent to the solenoid valves upstream and downstream of the visualization cell for trapping the particle in the visualization cell. The motion of particle in the visualization cell was monitored by CCD camera and the gravitational settling velocity and the electrostatic migration velocity were measured from the video image. The aerodynamic diameter obtained from the settling velocity was in good agreement with Stokes diameter calculated from the electrostatic migration velocity for individual particles. It was also found that the aerodynamic diameter obtained from the settling velocity was a one-to-one function of the scattered light intensity of individual particles. The applicability of this system will be discussed.

  7. The eye and visual nervous system: anatomy, physiology and toxicology.

    PubMed Central

    McCaa, C S

    1982-01-01

    The eyes are at risk to environmental injury by direct exposure to airborne pollutants, to splash injury from chemicals and to exposure via the circulatory system to numerous drugs and bloodborne toxins. In addition, drugs or toxins can destroy vision by damaging the visual nervous system. This review describes the anatomy and physiology of the eye and visual nervous system and includes a discussion of some of the more common toxins affecting vision in man. Images FIGURE 1. FIGURE 2. PMID:7084144

  8. A dysmorphology score system for assessing embryo abnormalities in rat whole embryo culture.

    PubMed

    Zhang, Cindy X; Danberry, Tracy; Jacobs, Mary Ann; Augustine-Rauch, Karen

    2010-12-01

    The rodent whole embryo culture (WEC) system is a well-established model for characterizing developmental toxicity of test compounds and conducting mechanistic studies. Laboratories have taken various approaches in describing type and severity of developmental findings of organogenesis-stage rodent embryos, but the Brown and Fabro morphological score system is commonly used as a quantitative approach. The associated score criteria is based upon developmental stage and growth parameters, where a series of embryonic structures are assessed and assigned respective scores relative to their gestational stage, with a Total Morphological Score (TMS) assigned to the embryo. This score system is beneficial because it assesses a series of stage-specific anatomical landmarks, facilitating harmonized evaluation across laboratories. Although the TMS provides a quantitative approach to assess growth and determine developmental delay, it is limited to its ability to identify and/or delineate subtle or structure-specific abnormalities. Because of this, the TMS may not be sufficiently sensitive for identifying compounds that induce structure or organ-selective effects. This study describes a distinct morphological score system called the "Dysmorphology Score System (DMS system)" that has been developed for assessing gestation day 11 (approximately 20-26 somite stage) rat embryos using numerical scores to differentiate normal from abnormal morphology and define the respective severity of dysmorphology of specific embryonic structures and organ systems. This method can also be used in scoring mouse embryos of the equivalent developmental stage. The DMS system enhances capabilities to rank-order compounds based upon teratogenic potency, conduct structure- relationships of chemicals, and develop statistical prediction models to support abbreviated developmental toxicity screens. © 2010 Wiley-Liss, Inc.

  9. Integrating visual learning within a model-based ATR system

    NASA Astrophysics Data System (ADS)

    Carlotto, Mark; Nebrich, Mark

    2017-05-01

    Automatic target recognition (ATR) systems, like human photo-interpreters, rely on a variety of visual information for detecting, classifying, and identifying manmade objects in aerial imagery. We describe the integration of a visual learning component into the Image Data Conditioner (IDC) for target/clutter and other visual classification tasks. The component is based on an implementation of a model of the visual cortex developed by Serre, Wolf, and Poggio. Visual learning in an ATR context requires the ability to recognize objects independent of location, scale, and rotation. Our method uses IDC to extract, rotate, and scale image chips at candidate target locations. A bootstrap learning method effectively extends the operation of the classifier beyond the training set and provides a measure of confidence. We show how the classifier can be used to learn other features that are difficult to compute from imagery such as target direction, and to assess the performance of the visual learning process itself.

  10. Retinal Structures and Visual Cortex Activity are Impaired Prior to Clinical Vision Loss in Glaucoma.

    PubMed

    Murphy, Matthew C; Conner, Ian P; Teng, Cindy Y; Lawrence, Jesse D; Safiullah, Zaid; Wang, Bo; Bilonick, Richard A; Kim, Seong-Gi; Wollstein, Gadi; Schuman, Joel S; Chan, Kevin C

    2016-08-11

    Glaucoma is the second leading cause of blindness worldwide and its pathogenesis remains unclear. In this study, we measured the structure, metabolism and function of the visual system by optical coherence tomography and multi-modal magnetic resonance imaging in healthy subjects and glaucoma patients with different degrees of vision loss. We found that inner retinal layer thinning, optic nerve cupping and reduced visual cortex activity occurred before patients showed visual field impairment. The primary visual cortex also exhibited more severe functional deficits than higher-order visual brain areas in glaucoma. Within the visual cortex, choline metabolism was perturbed along with increasing disease severity in the eye, optic radiation and visual field. In summary, this study showed evidence that glaucoma deterioration is already present in the eye and the brain before substantial vision loss can be detected clinically using current testing methods. In addition, cortical cholinergic abnormalities are involved during trans-neuronal degeneration and can be detected non-invasively in glaucoma. The current results can be of impact for identifying early glaucoma mechanisms, detecting and monitoring pathophysiological events and eye-brain-behavior relationships, and guiding vision preservation strategies in the visual system, which may help reduce the burden of this irreversible but preventable neurodegenerative disease.

  11. Retinal Structures and Visual Cortex Activity are Impaired Prior to Clinical Vision Loss in Glaucoma

    PubMed Central

    Murphy, Matthew C.; Conner, Ian P.; Teng, Cindy Y.; Lawrence, Jesse D.; Safiullah, Zaid; Wang, Bo; Bilonick, Richard A.; Kim, Seong-Gi; Wollstein, Gadi; Schuman, Joel S.; Chan, Kevin C.

    2016-01-01

    Glaucoma is the second leading cause of blindness worldwide and its pathogenesis remains unclear. In this study, we measured the structure, metabolism and function of the visual system by optical coherence tomography and multi-modal magnetic resonance imaging in healthy subjects and glaucoma patients with different degrees of vision loss. We found that inner retinal layer thinning, optic nerve cupping and reduced visual cortex activity occurred before patients showed visual field impairment. The primary visual cortex also exhibited more severe functional deficits than higher-order visual brain areas in glaucoma. Within the visual cortex, choline metabolism was perturbed along with increasing disease severity in the eye, optic radiation and visual field. In summary, this study showed evidence that glaucoma deterioration is already present in the eye and the brain before substantial vision loss can be detected clinically using current testing methods. In addition, cortical cholinergic abnormalities are involved during trans-neuronal degeneration and can be detected non-invasively in glaucoma. The current results can be of impact for identifying early glaucoma mechanisms, detecting and monitoring pathophysiological events and eye-brain-behavior relationships, and guiding vision preservation strategies in the visual system, which may help reduce the burden of this irreversible but preventable neurodegenerative disease. PMID:27510406

  12. Improving the performance of the amblyopic visual system

    PubMed Central

    Levi, Dennis M.; Li, Roger W.

    2008-01-01

    Experience-dependent plasticity is closely linked with the development of sensory function; however, there is also growing evidence for plasticity in the adult visual system. This review re-examines the notion of a sensitive period for the treatment of amblyopia in the light of recent experimental and clinical evidence for neural plasticity. One recently proposed method for improving the effectiveness and efficiency of treatment that has received considerable attention is ‘perceptual learning’. Specifically, both children and adults with amblyopia can improve their perceptual performance through extensive practice on a challenging visual task. The results suggest that perceptual learning may be effective in improving a range of visual performance and, importantly, the improvements may transfer to visual acuity. Recent studies have sought to explore the limits and time course of perceptual learning as an adjunct to occlusion and to investigate the neural mechanisms underlying the visual improvement. These findings, along with the results of new clinical trials, suggest that it might be time to reconsider our notions about neural plasticity in amblyopia. PMID:19008199

  13. The µ-opioid system promotes visual attention to faces and eyes.

    PubMed

    Chelnokova, Olga; Laeng, Bruno; Løseth, Guro; Eikemo, Marie; Willoch, Frode; Leknes, Siri

    2016-12-01

    Paying attention to others' faces and eyes is a cornerstone of human social behavior. The µ-opioid receptor (MOR) system, central to social reward-processing in rodents and primates, has been proposed to mediate the capacity for affiliative reward in humans. We assessed the role of the human MOR system in visual exploration of faces and eyes of conspecifics. Thirty healthy males received a novel, bidirectional battery of psychopharmacological treatment (an MOR agonist, a non-selective opioid antagonist, or placebo, on three separate days). Eye-movements were recorded while participants viewed facial photographs. We predicted that the MOR system would promote visual exploration of faces, and hypothesized that MOR agonism would increase, whereas antagonism decrease overt attention to the information-rich eye region. The expected linear effect of MOR manipulation on visual attention to the stimuli was observed, such that MOR agonism increased while antagonism decreased visual exploration of faces and overt attention to the eyes. The observed effects suggest that the human MOR system promotes overt visual attention to socially significant cues, in line with theories linking reward value to gaze control and target selection. Enhanced attention to others' faces and eyes represents a putative behavioral mechanism through which the human MOR system promotes social interest. © The Author (2016). Published by Oxford University Press. For Permissions, please email: journals.permissions@oup.com.

  14. Parallel Processing Strategies of the Primate Visual System

    PubMed Central

    Nassi, Jonathan J.; Callaway, Edward M.

    2009-01-01

    Preface Incoming sensory information is sent to the brain along modality-specific channels corresponding to the five senses. Each of these channels further parses the incoming signals into parallel streams to provide a compact, efficient input to the brain. Ultimately, these parallel input signals must be elaborated upon and integrated within the cortex to provide a unified and coherent percept. Recent studies in the primate visual cortex have greatly contributed to our understanding of how this goal is accomplished. Multiple strategies including retinal tiling, hierarchical and parallel processing and modularity, defined spatially and by cell type-specific connectivity, are all used by the visual system to recover the rich detail of our visual surroundings. PMID:19352403

  15. COALA-System for Visual Representation of Cryptography Algorithms

    ERIC Educational Resources Information Center

    Stanisavljevic, Zarko; Stanisavljevic, Jelena; Vuletic, Pavle; Jovanovic, Zoran

    2014-01-01

    Educational software systems have an increasingly significant presence in engineering sciences. They aim to improve students' attitudes and knowledge acquisition typically through visual representation and simulation of complex algorithms and mechanisms or hardware systems that are often not available to the educational institutions. This paper…

  16. A web-based 3D geological information visualization system

    NASA Astrophysics Data System (ADS)

    Song, Renbo; Jiang, Nan

    2013-03-01

    Construction of 3D geological visualization system has attracted much more concern in GIS, computer modeling, simulation and visualization fields. It not only can effectively help geological interpretation and analysis work, but also can it can help leveling up geosciences professional education. In this paper, an applet-based method was introduced for developing a web-based 3D geological information visualization system. The main aims of this paper are to explore a rapid and low-cost development method for constructing a web-based 3D geological system. First, the borehole data stored in Excel spreadsheets was extracted and then stored in SQLSERVER database of a web server. Second, the JDBC data access component was utilized for providing the capability of access the database. Third, the user interface was implemented with applet component embedded in JSP page and the 3D viewing and querying functions were implemented with PickCanvas of Java3D. Last, the borehole data acquired from geological survey were used for test the system, and the test results has shown that related methods of this paper have a certain application values.

  17. A Prototype Flight-Deck Airflow Hazard Visualization System

    NASA Technical Reports Server (NTRS)

    Aragon, Cecilia R.

    2004-01-01

    Airflow hazards such as turbulence, vortices, or low-level wind shear can pose a threat to landing aircraft and are especially dangerous to helicopters. Because pilots usually cannot see airflow, they may be unaware of the extent of the hazard. We have developed a prototype airflow hazard visual display for use in helicopter cockpits to alleviate this problem. We report on the results of a preliminary usability study of our airflow hazard visualization system in helicopter-shipboard operations.

  18. How cortical neurons help us see: visual recognition in the human brain

    PubMed Central

    Blumberg, Julie; Kreiman, Gabriel

    2010-01-01

    Through a series of complex transformations, the pixel-like input to the retina is converted into rich visual perceptions that constitute an integral part of visual recognition. Multiple visual problems arise due to damage or developmental abnormalities in the cortex of the brain. Here, we provide an overview of how visual information is processed along the ventral visual cortex in the human brain. We discuss how neurophysiological recordings in macaque monkeys and in humans can help us understand the computations performed by visual cortex. PMID:20811161

  19. Conceptual design study for an advanced cab and visual system, volume 2

    NASA Technical Reports Server (NTRS)

    Rue, R. J.; Cyrus, M. L.; Garnett, T. A.; Nachbor, J. W.; Seery, J. A.; Starr, R. L.

    1980-01-01

    The performance, design, construction and testing requirements are defined for developing an advanced cab and visual system. The rotorcraft system integration simulator is composed of the advanced cab and visual system and the rotorcraft system motion generator, and is part of an existing simulation facility. User's applications for the simulator include rotorcraft design development, product improvement, threat assessment, and accident investigation.

  20. Comparison of multifocal visual evoked potential, static automated perimetry, and optical coherence tomography findings for assessing visual pathways in patients with pituitary adenomas.

    PubMed

    Qiao, Nidan; Zhang, Yichao; Ye, Zhao; Shen, Ming; Shou, Xuefei; Wang, Yongfei; Li, Shiqi; Wang, Min; Zhao, Yao

    2015-10-01

    There have been no studies investigating the correlation between structural [thickness of the retinal nerve fiber layer (RNFL) as determined by optical coherence tomography (OCT)] and functional [Humphrey visual field (HVF) or visual evoked potential (VEP) amplitude] measures of optic nerve integrity in patients with pituitary adenomas (PA). Patients with PAs were recruited between September 2010 and September 2013. OCT, standard automated perimetry (SAP), and multifical VEP (mfVEP) were performed. Agreement between OCT, SAP, and mfVEP values in classifying eyes/quadrants was determined using AC1 statistics. Pearson's correlation was used to examine relationships between structural and functional data. In total, 88.7% of the eyes tested showed abnormal SAP findings and 93.7% showed abnormal mfVEP findings. Only 14.8% of the eyes showed abnormal OCT findings. The agreement between SAP and mfVEP findings was 88.9% (AC1 = 0.87). The agreement between OCT and mfVEP findings was 24.2% (AC1 = -0.52), and that between OCT and SAP findings was 21.5% (AC1 = -0.56). The correlation values between RNFL thickness and the functional measurements were -0.601 for the mfVEP score (P = 0.000) and -0.441 for the SAP score (P = 0.000). The correlation between the mfVEP and SAP scores was -0.617 (P = 0.000). mfVEP, SAP, and OCT provided complementary information for detecting visual pathway abnormalities in patients with PAs. Good agreement was demonstrated between SAP and mfVEP and quantitative analysis of structure-function measurements revealed a moderate correlation.

  1. Grey matter connectivity within and between auditory, language and visual systems in prelingually deaf adolescents.

    PubMed

    Li, Wenjing; Li, Jianhong; Wang, Zhenchang; Li, Yong; Liu, Zhaohui; Yan, Fei; Xian, Junfang; He, Huiguang

    2015-01-01

    Previous studies have shown brain reorganizations after early deprivation of auditory sensory. However, changes of grey matter connectivity have not been investigated in prelingually deaf adolescents yet. In the present study, we aimed to investigate changes of grey matter connectivity within and between auditory, language and visual systems in prelingually deaf adolescents. We recruited 16 prelingually deaf adolescents and 16 age-and gender-matched normal controls, and extracted the grey matter volume as the structural characteristic from 14 regions of interest involved in auditory, language or visual processing to investigate the changes of grey matter connectivity within and between auditory, language and visual systems. Sparse inverse covariance estimation (SICE) was utilized to construct grey matter connectivity between these brain regions. The results show that prelingually deaf adolescents present weaker grey matter connectivity within auditory and visual systems, and connectivity between language and visual systems declined. Notably, significantly increased brain connectivity was found between auditory and visual systems in prelingually deaf adolescents. Our results indicate "cross-modal" plasticity after deprivation of the auditory input in prelingually deaf adolescents, especially between auditory and visual systems. Besides, auditory deprivation and visual deficits might affect the connectivity pattern within language and visual systems in prelingually deaf adolescents.

  2. Virtual Earth System Laboratory (VESL): Effective Visualization of Earth System Data and Process Simulations

    NASA Astrophysics Data System (ADS)

    Quinn, J. D.; Larour, E. Y.; Cheng, D. L. C.; Halkides, D. J.

    2016-12-01

    The Virtual Earth System Laboratory (VESL) is a Web-based tool, under development at the Jet Propulsion Laboratory and UC Irvine, for the visualization of Earth System data and process simulations. It contains features geared toward a range of applications, spanning research and outreach. It offers an intuitive user interface, in which model inputs are changed using sliders and other interactive components. Current capabilities include simulation of polar ice sheet responses to climate forcing, based on NASA's Ice Sheet System Model (ISSM). We believe that the visualization of data is most effective when tailored to the target audience, and that many of the best practices for modern Web design/development can be applied directly to the visualization of data: use of negative space, color schemes, typography, accessibility standards, tooltips, etc cetera. We present our prototype website, and invite input from potential users, including researchers, educators, and students.

  3. Performance evaluation of a dynamic telepathology system (Panoptiq™) in the morphologic assessment of peripheral blood film abnormalities.

    PubMed

    Goswami, R; Pi, D; Pal, J; Cheng, K; Hudoba De Badyn, M

    2015-06-01

    The study evaluated the performance of a dynamic imaging telepathology system (Panoptiq(™) ) as a diagnostic aid to the identification of peripheral blood film (PBF) abnormalities. The study assumed a laboratory personnel working in a clinical laboratory were operating the telepathology system to seek diagnostic opinion from an external consulting hematopathologist. The study examined 100 blood films, encompassing 23 different hematological diseases, reactive or normal cases. The study revealed that with real-time image transmission in live scanning mode of operation, the telepathology system was able to aid reviewers in achieving excellent accuracy, that is correct interpretation of morphologic abnormalities obtained in 83/84 of the hematologic diseases and 12/12 of the reactive/normal conditions (Sensitivity: 0.99; Specificity: 1.00). In contrast, when only saved static images in digital capture mode of operation were reviewed remotely, interpretative omissions occurred in 8/84 of the hematologic diseases and 0/12 of the reactive/normal conditions (Sensitivity: 0.91; Specificity: 1.00). It is hypothesized that real-time operator-reviewer communication during live scanning played an important role in the identification of key morphologic abnormalities for review. Our study showed the Panoptiq system can be adopted reliably as a dynamic telepathology tool in aiding community laboratories in the triage of PBF cases for external diagnostic consultation. © 2014 John Wiley & Sons Ltd.

  4. Integrated voice and visual systems research topics

    NASA Technical Reports Server (NTRS)

    Williams, Douglas H.; Simpson, Carol A.

    1986-01-01

    A series of studies was performed to investigate factors of helicopter speech and visual system design and measure the effects of these factors on human performance, both for pilots and non-pilots. The findings and conclusions of these studies were applied by the U.S. Army to the design of the Army's next generation threat warning system for helicopters and to the linguistic functional requirements for a joint Army/NASA flightworthy, experimental speech generation and recognition system.

  5. A computer graphics system for visualizing spacecraft in orbit

    NASA Technical Reports Server (NTRS)

    Eyles, Don E.

    1989-01-01

    To carry out unanticipated operations with resources already in space is part of the rationale for a permanently manned space station in Earth orbit. The astronauts aboard a space station will require an on-board, spatial display tool to assist the planning and rehearsal of upcoming operations. Such a tool can also help astronauts to monitor and control such operations as they occur, especially in cases where first-hand visibility is not possible. A computer graphics visualization system designed for such an application and currently implemented as part of a ground-based simulation is described. The visualization system presents to the user the spatial information available in the spacecraft's computers by drawing a dynamic picture containing the planet Earth, the Sun, a star field, and up to two spacecraft. The point of view within the picture can be controlled by the user to obtain a number of specific visualization functions. The elements of the display, the methods used to control the display's point of view, and some of the ways in which the system can be used are described.

  6. Patient DF's visual brain in action: Visual feedforward control in visual form agnosia.

    PubMed

    Whitwell, Robert L; Milner, A David; Cavina-Pratesi, Cristiana; Barat, Masihullah; Goodale, Melvyn A

    2015-05-01

    Patient DF, who developed visual form agnosia following ventral-stream damage, is unable to discriminate the width of objects, performing at chance, for example, when asked to open her thumb and forefinger a matching amount. Remarkably, however, DF adjusts her hand aperture to accommodate the width of objects when reaching out to pick them up (grip scaling). While this spared ability to grasp objects is presumed to be mediated by visuomotor modules in her relatively intact dorsal stream, it is possible that it may rely abnormally on online visual or haptic feedback. We report here that DF's grip scaling remained intact when her vision was completely suppressed during grasp movements, and it still dissociated sharply from her poor perceptual estimates of target size. We then tested whether providing trial-by-trial haptic feedback after making such perceptual estimates might improve DF's performance, but found that they remained significantly impaired. In a final experiment, we re-examined whether DF's grip scaling depends on receiving veridical haptic feedback during grasping. In one condition, the haptic feedback was identical to the visual targets. In a second condition, the haptic feedback was of a constant intermediate width while the visual target varied trial by trial. Despite this incongruent feedback, DF still scaled her grip aperture to the visual widths of the target blocks, showing only normal adaptation to the false haptically-experienced width. Taken together, these results strengthen the view that DF's spared grasping relies on a normal mode of dorsal-stream functioning, based chiefly on visual feedforward processing. Copyright © 2014 Elsevier B.V. All rights reserved.

  7. Delayed Early Primary Visual Pathway Development in Premature Infants: High Density Electrophysiological Evidence

    PubMed Central

    Tremblay, Emmanuel; Vannasing, Phetsamone; Roy, Marie-Sylvie; Lefebvre, Francine; Kombate, Damelan; Lassonde, Maryse; Lepore, Franco; McKerral, Michelle; Gallagher, Anne

    2014-01-01

    In the past decades, multiple studies have been interested in developmental patterns of the visual system in healthy infants. During the first year of life, differential maturational changes have been observed between the Magnocellular (P) and the Parvocellular (P) visual pathways. However, few studies investigated P and M system development in infants born prematurely. The aim of the present study was to characterize P and M system maturational differences between healthy preterm and fullterm infants through a critical period of visual maturation: the first year of life. Using a cross-sectional design, high-density electroencephalogram (EEG) was recorded in 31 healthy preterms and 41 fullterm infants of 3, 6, or 12 months (corrected age for premature babies). Three visual stimulations varying in contrast and spatial frequency were presented to stimulate preferentially the M pathway, the P pathway, or both systems simultaneously during EEG recordings. Results from early visual evoked potentials in response to the stimulation that activates simultaneously both systems revealed longer N1 latencies and smaller P1 amplitudes in preterm infants compared to fullterms. Moreover, preterms showed longer N1 and P1 latencies in response to stimuli assessing the M pathway at 3 months. No differences between preterms and fullterms were found when using the preferential P system stimulation. In order to identify the cerebral generator of each visual response, distributed source analyses were computed in 12-month-old infants using LORETA. Source analysis demonstrated an activation of the parietal dorsal region in fullterm infants, in response to the preferential M pathway, which was not seen in the preterms. Overall, these findings suggest that the Magnocellular pathway development is affected in premature infants. Although our VEP results suggest that premature children overcome, at least partially, the visual developmental delay with time, source analyses reveal abnormal brain

  8. Intrusion Detection System Visualization of Network Alerts

    DTIC Science & Technology

    2010-07-01

    Intrusion Detection System Visualization of Network Alerts Dolores M. Zage and Wayne M. Zage Ball State University Final Report July 2010...contracts. Staff Wayne Zage, Director of the S2ERC and Professor, Department of Computer Science, Ball State University Dolores Zage, Research

  9. Visualization of reservoir simulation data with an immersive virtual reality system

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Williams, B.K.

    1996-10-01

    This paper discusses an investigation into the use of an immersive virtual reality (VR) system to visualize reservoir simulation output data. The hardware and software configurations of the test-immersive VR system are described and compared to a nonimmersive VR system and to an existing workstation screen-based visualization system. The structure of 3D reservoir simulation data and the actions to be performed on the data within the VR system are discussed. The subjective results of the investigation are then presented, followed by a discussion of possible future work.

  10. Feedforward and feedback motor control abnormalities implicate cerebellar dysfunctions in autism spectrum disorder.

    PubMed

    Mosconi, Matthew W; Mohanty, Suman; Greene, Rachel K; Cook, Edwin H; Vaillancourt, David E; Sweeney, John A

    2015-02-04

    Sensorimotor abnormalities are common in autism spectrum disorder (ASD) and among the earliest manifestations of the disorder. They have been studied far less than the social-communication and cognitive deficits that define ASD, but a mechanistic understanding of sensorimotor abnormalities in ASD may provide key insights into the neural underpinnings of the disorder. In this human study, we examined rapid, precision grip force contractions to determine whether feedforward mechanisms supporting initial motor output before sensory feedback can be processed are disrupted in ASD. Sustained force contractions also were examined to determine whether reactive adjustments to ongoing motor behavior based on visual feedback are altered. Sustained force was studied across multiple force levels and visual gains to assess motor and visuomotor mechanisms, respectively. Primary force contractions of individuals with ASD showed greater peak rate of force increases and large transient overshoots. Individuals with ASD also showed increased sustained force variability that scaled with force level and was more severe when visual gain was highly amplified or highly degraded. When sustaining a constant force level, their reactive adjustments were more periodic than controls, and they showed increased reliance on slower feedback mechanisms. Feedforward and feedback mechanism alterations each were associated with more severe social-communication impairments in ASD. These findings implicate anterior cerebellar circuits involved in feedforward motor control and posterior cerebellar circuits involved in transforming visual feedback into precise motor adjustments in ASD. Copyright © 2015 the authors 0270-6474/15/352015-11$15.00/0.

  11. Feedforward and Feedback Motor Control Abnormalities Implicate Cerebellar Dysfunctions in Autism Spectrum Disorder

    PubMed Central

    Mohanty, Suman; Greene, Rachel K.; Cook, Edwin H.; Vaillancourt, David E.; Sweeney, John A.

    2015-01-01

    Sensorimotor abnormalities are common in autism spectrum disorder (ASD) and among the earliest manifestations of the disorder. They have been studied far less than the social-communication and cognitive deficits that define ASD, but a mechanistic understanding of sensorimotor abnormalities in ASD may provide key insights into the neural underpinnings of the disorder. In this human study, we examined rapid, precision grip force contractions to determine whether feedforward mechanisms supporting initial motor output before sensory feedback can be processed are disrupted in ASD. Sustained force contractions also were examined to determine whether reactive adjustments to ongoing motor behavior based on visual feedback are altered. Sustained force was studied across multiple force levels and visual gains to assess motor and visuomotor mechanisms, respectively. Primary force contractions of individuals with ASD showed greater peak rate of force increases and large transient overshoots. Individuals with ASD also showed increased sustained force variability that scaled with force level and was more severe when visual gain was highly amplified or highly degraded. When sustaining a constant force level, their reactive adjustments were more periodic than controls, and they showed increased reliance on slower feedback mechanisms. Feedforward and feedback mechanism alterations each were associated with more severe social-communication impairments in ASD. These findings implicate anterior cerebellar circuits involved in feedforward motor control and posterior cerebellar circuits involved in transforming visual feedback into precise motor adjustments in ASD. PMID:25653359

  12. Two different streams form the dorsal visual system: anatomy and functions.

    PubMed

    Rizzolatti, Giacomo; Matelli, Massimo

    2003-11-01

    There are two radically different views on the functional role of the dorsal visual stream. One considers it as a system involved in space perception. The other is of a system that codes visual information for action organization. On the basis of new anatomical data and a reconsideration of previous functional and clinical data, we propose that the dorsal stream and its recipient parietal areas form two distinct functional systems: the dorso-dorsal stream (d-d stream) and the ventro-dorsal stream (v-d stream). The d-d stream is formed by area V6 (main d-d extrastriate visual node) and areas V6A and MIP of the superior parietal lobule. Its major functional role is the control of actions "on line". Its damage leads to optic ataxia. The v-d stream is formed by area MT (main v-d extrastriate visual node) and by the visual areas of the inferior parietal lobule. As the d-d stream, v-d stream is responsible for action organization. It, however, also plays a crucial role in space perception and action understanding. The putative mechanisms linking action and perception in the v-d stream is discussed.

  13. Abnormal Size-Dependent Modulation of Motion Perception in Children with Autism Spectrum Disorder (ASD).

    PubMed

    Sysoeva, Olga V; Galuta, Ilia A; Davletshina, Maria S; Orekhova, Elena V; Stroganova, Tatiana A

    2017-01-01

    Excitation/Inhibition (E/I) imbalance in neural networks is now considered among the core neural underpinnings of autism psychopathology. In motion perception at least two phenomena critically depend on E/I balance in visual cortex: spatial suppression (SS), and spatial facilitation (SF) corresponding to impoverished or improved motion perception with increasing stimuli size, respectively. While SS is dominant at high contrast, SF is evident for low contrast stimuli, due to the prevalence of inhibitory contextual modulations in the former, and excitatory ones in the latter case. Only one previous study (Foss-Feig et al., 2013) investigated SS and SF in Autism Spectrum Disorder (ASD). Our study aimed to replicate previous findings, and to explore the putative contribution of deficient inhibitory influences into an enhanced SF index in ASD-a cornerstone for interpretation proposed by Foss-Feig et al. (2013). The SS and SF were examined in 40 boys with ASD, broad spectrum of intellectual abilities (63 < IQ < 127) and 44 typically developing (TD) boys, aged 6-15 years. The stimuli of small (1°) and large (12°) radius were presented under high (100%) and low (1%) contrast conditions. Social Responsiveness Scale and Sensory Profile Questionnaire were used to assess the autism severity and sensory processing abnormalities. We found that the SS index was atypically reduced, while SF index abnormally enhanced in children with ASD. The presence of abnormally enhanced SF in children with ASD was the only consistent finding between our study and that of Foss-Feig et al. While the SS and SF indexes were strongly interrelated in TD participants, this correlation was absent in their peers with ASD. In addition, the SF index but not the SS index correlated with the severity of autism and the poor registration abilities. The pattern of results is partially consistent with the idea of hypofunctional inhibitory transmission in visual areas in ASD. Nonetheless, the absence of

  14. Abnormal Size-Dependent Modulation of Motion Perception in Children with Autism Spectrum Disorder (ASD)

    PubMed Central

    Sysoeva, Olga V.; Galuta, Ilia A.; Davletshina, Maria S.; Orekhova, Elena V.; Stroganova, Tatiana A.

    2017-01-01

    Excitation/Inhibition (E/I) imbalance in neural networks is now considered among the core neural underpinnings of autism psychopathology. In motion perception at least two phenomena critically depend on E/I balance in visual cortex: spatial suppression (SS), and spatial facilitation (SF) corresponding to impoverished or improved motion perception with increasing stimuli size, respectively. While SS is dominant at high contrast, SF is evident for low contrast stimuli, due to the prevalence of inhibitory contextual modulations in the former, and excitatory ones in the latter case. Only one previous study (Foss-Feig et al., 2013) investigated SS and SF in Autism Spectrum Disorder (ASD). Our study aimed to replicate previous findings, and to explore the putative contribution of deficient inhibitory influences into an enhanced SF index in ASD—a cornerstone for interpretation proposed by Foss-Feig et al. (2013). The SS and SF were examined in 40 boys with ASD, broad spectrum of intellectual abilities (63 < IQ < 127) and 44 typically developing (TD) boys, aged 6–15 years. The stimuli of small (1°) and large (12°) radius were presented under high (100%) and low (1%) contrast conditions. Social Responsiveness Scale and Sensory Profile Questionnaire were used to assess the autism severity and sensory processing abnormalities. We found that the SS index was atypically reduced, while SF index abnormally enhanced in children with ASD. The presence of abnormally enhanced SF in children with ASD was the only consistent finding between our study and that of Foss-Feig et al. While the SS and SF indexes were strongly interrelated in TD participants, this correlation was absent in their peers with ASD. In addition, the SF index but not the SS index correlated with the severity of autism and the poor registration abilities. The pattern of results is partially consistent with the idea of hypofunctional inhibitory transmission in visual areas in ASD. Nonetheless, the absence of

  15. Toward a Scalable Visualization System for Network Traffic Monitoring

    NASA Astrophysics Data System (ADS)

    Malécot, Erwan Le; Kohara, Masayoshi; Hori, Yoshiaki; Sakurai, Kouichi

    With the multiplication of attacks against computer networks, system administrators are required to monitor carefully the traffic exchanged by the networks they manage. However, that monitoring task is increasingly laborious because of the augmentation of the amount of data to analyze. And that trend is going to intensify with the explosion of the number of devices connected to computer networks along with the global rise of the available network bandwidth. So system administrators now heavily rely on automated tools to assist them and simplify the analysis of the data. Yet, these tools provide limited support and, most of the time, require highly skilled operators. Recently, some research teams have started to study the application of visualization techniques to the analysis of network traffic data. We believe that this original approach can also allow system administrators to deal with the large amount of data they have to process. In this paper, we introduce a tool for network traffic monitoring using visualization techniques that we developed in order to assist the system administrators of our corporate network. We explain how we designed the tool and some of the choices we made regarding the visualization techniques to use. The resulting tool proposes two linked representations of the network traffic and activity, one in 2D and the other in 3D. As 2D and 3D visualization techniques have different assets, we resulted in combining them in our tool to take advantage of their complementarity. We finally tested our tool in order to evaluate the accuracy of our approach.

  16. Moderate Perinatal Thyroid Hormone Insufficiency Alters Visual System Function in Adult Rats

    EPA Science Inventory

    Thyroid hormone (TH) is critical for many aspects of neurodevelopment, such as the visual system, but may be disrupted by many environmental contaminants. The experimental data demonstrating a role for TH on visual system development generally derives from studies in which deve...

  17. Designing and visualizing the water-energy-food nexus system

    NASA Astrophysics Data System (ADS)

    Endo, A.; Kumazawa, T.; Yamada, M.; Kato, T.

    2017-12-01

    The objective of this study is to design and visualize a water-energy-food nexus system to identify the interrelationships between water-energy-food (WEF) resources and to understand the subsequent complexity of WEF nexus systems holistically, taking an interdisciplinary approach. Object-oriented concepts and ontology engineering methods were applied according to the hypothesis that the chains of changes in linkages between water, energy, and food resources holistically affect the water-energy-food nexus system, including natural and social systems, both temporally and spatially. The water-energy-food nexus system that is developed is significant because it allows us to: 1) visualize linkages between water, energy, and food resources in social and natural systems; 2) identify tradeoffs between these resources; 3) find a way of using resources efficiently or enhancing the synergy between the utilization of different resources; and 4) aid scenario planning using economic tools. The paper also discusses future challenges for applying the developed water-energy-food nexus system in other areas.

  18. Relationship Between Rates of Binocular Visual Field Loss and Vision-Related Quality of Life in Glaucoma

    PubMed Central

    Lisboa, Renato; Chun, Yeoun Sook; Zangwill, Linda M.; Weinreb, Robert N.; Rosen, Peter N.; Liebmann, Jeffrey M.; Girkin, Christopher A.; Medeiros, Felipe A.

    2013-01-01

    Objective To evaluate the relationship between binocular rates of visual field change and vision-related quality of life (VRQOL) in glaucoma. Methods The study included 796 eyes of 398 participants that had diagnosed or suspected glaucoma followed for an average of 7.3 ± 2.0 years. Subjects were recruited from the Diagnostic Innovations in Glaucoma Study (DIGS) and the African Descent and Glaucoma Evaluation Study (ADAGES). VRQOL was evaluated using the National Eye Institute Visual Function Questionnaire (NEI VFQ-25) at the last follow-up visit. Integrated binocular visual fields (BVF) were calculated from the monocular fields of each patient. Linear regression of mean deviation (MD) values was used to evaluate rates of visual field change during the follow-up period. Logistic regression models were used to investigate the relationship between abnormal VRQOL and rates of visual field change, while adjusting for potentially confounding socio-economic and demographic variables. Results Thirty-two patients (8.0%) had abnormal VRQOL as determined by the results of the NEI VFQ-25 questionnaire. Subjects with abnormal VRQOL had significantly faster rates of BVF change than those with normal VRQOL (−0.18 db/year vs. −0.06 dB/year, respectively; P < 0.001). Rates of BVF change were significantly associated with abnormality in VRQOL (OR = 1.31 per 0.1dB/year faster; P = 0.038), after adjustment for confounding variables. Conclusions Patients with faster rates of BVF change were at higher risk of reporting abnormal VRQOL. Assessment of rates of BVF change may provide useful information in determining risk of functional impairment in glaucoma. PMID:23450425

  19. VISUAL ACUITY IN PSEUDOXANTHOMA ELASTICUM.

    PubMed

    Risseeuw, Sara; Ossewaarde-van Norel, Jeannette; Klaver, Caroline C W; Colijn, Johanna M; Imhof, Saskia M; van Leeuwen, Redmer

    2018-04-12

    To assess the age-specific proportion of visual impairment in patients with pseudoxanthoma elasticum (PXE) and to compare this with foveal abnormality and similar data of late age-related macular degeneration patients. Cross-sectional data of 195 patients with PXE were reviewed, including best-corrected visual acuity and imaging. The World Health Organisation criteria were used to categorize bilateral visual impairment. These results were compared with similar data of 131 patients with late age-related macular degeneration from the Rotterdam study. Overall, 50 PXE patients (26.0%) were visually impaired, including 21 (11%) with legal blindness. Visual functioning declined with increasing age. In patients older than 50 years, 37% was visually impaired and 15% legally blind. Foveal choroidal neovascularization was found in 84% of eyes with a best-corrected visual acuity lower than 20/70 (0.30) and macular atrophy in the fovea in 16%. In late age-related macular degeneration patients, 40% were visually impaired and 13% legally blind. Visual impairment started approximately 20 years later as compared with PXE patients. Visual impairment and blindness are frequent in PXE, particularly in patients older than 50 years. Although choroidal neovascularization is associated with the majority of vision loss, macular atrophy is also common. The proportion of visual impairment in PXE is comparable with late age-related macular degeneration but manifests earlier in life.

  20. A novel scoring system to measure radiographic abnormalities and related spirometric values in cured pulmonary tuberculosis.

    PubMed

    Báez-Saldaña, Renata; López-Arteaga, Yesenia; Bizarrón-Muro, Alma; Ferreira-Guerrero, Elizabeth; Ferreyra-Reyes, Leticia; Delgado-Sánchez, Guadalupe; Cruz-Hervert, Luis Pablo; Mongua-Rodríguez, Norma; García-García, Lourdes

    2013-01-01

    Despite chemotherapy, patients with cured pulmonary tuberculosis may result in lung functional impairment. To evaluate a novel scoring system based on the degree of radiographic abnormalities and related spirometric values in patients with cured pulmonary tuberculosis. One hundred and twenty seven patients with cured pulmonary tuberculosis were prospectively enrolled in a referral hospital specializing in respiratory diseases. Spirometry was performed and the extent of radiographic abnormalities was evaluated twice by each of two readers to generate a novel quantitative score. Scoring reproducibility was analyzed by the intra-class correlation coefficient (ICC) and the Bland-Altman method. Multiple linear regression models were performed to assess the association of the extent of radiographic abnormalities with spirometric values. The intra-observer agreement for scoring of radiographic abnormalities (SRA) showed an ICC of 0.81 (CI:95%, 0.67-0.95) and 0.78 (CI:95%, 0.65-0.92), for reader 1 and 2, respectively. Inter-observer reproducibility for the first measurement was 0.83 (CI:95%, 0.71-0.95), and for the second measurement was 0.74 (CI:95%, 0.58-0.90). The Bland-Altman analysis of the intra-observer agreement showed a mean bias of 0.87% and -0.55% and an inter-observer agreement of -0.35% and -1.78%, indicating a minor average systematic variability. After adjustment for age, gender, height, smoking status, pack-years of smoking, and degree of dyspnea, the scoring degree of radiographic abnormalities was significantly and negatively associated with absolute and percent predicted values of FVC: -0.07 (CI:95%, -0.01 to -0.04); -2.48 (CI:95%, -3.45 to -1.50); and FEV1 -0.07 (CI:95%, -0.10 to -0.05); -2.92 (CI:95%, -3.87 to -1.97) respectively, in the patients studied. The extent of radiographic abnormalities, as evaluated through our novel scoring system, was inversely associated with spirometric values, and exhibited good reliability and reproducibility. As intra

  1. A Novel Scoring System to Measure Radiographic Abnormalities and Related Spirometric Values in Cured Pulmonary Tuberculosis

    PubMed Central

    Báez-Saldaña, Renata; López-Arteaga, Yesenia; Bizarrón-Muro, Alma; Ferreira-Guerrero, Elizabeth; Ferreyra-Reyes, Leticia; Delgado-Sánchez, Guadalupe; Cruz-Hervert, Luis Pablo; Mongua-Rodríguez, Norma; García-García, Lourdes

    2013-01-01

    Background Despite chemotherapy, patients with cured pulmonary tuberculosis may result in lung functional impairment. Objective To evaluate a novel scoring system based on the degree of radiographic abnormalities and related spirometric values in patients with cured pulmonary tuberculosis. Methods One hundred and twenty seven patients with cured pulmonary tuberculosis were prospectively enrolled in a referral hospital specializing in respiratory diseases. Spirometry was performed and the extent of radiographic abnormalities was evaluated twice by each of two readers to generate a novel quantitative score. Scoring reproducibility was analyzed by the intra-class correlation coefficient (ICC) and the Bland-Altman method. Multiple linear regression models were performed to assess the association of the extent of radiographic abnormalities with spirometric values. Results The intra-observer agreement for scoring of radiographic abnormalities (SRA) showed an ICC of 0.81 (CI:95%, 0.67–0.95) and 0.78 (CI:95%, 0.65–0.92), for reader 1 and 2, respectively. Inter-observer reproducibility for the first measurement was 0.83 (CI:95%, 0.71–0.95), and for the second measurement was 0.74 (CI:95%, 0.58–0.90). The Bland-Altman analysis of the intra-observer agreement showed a mean bias of 0.87% and -0.55% and an inter-observer agreement of -0.35% and -1.78%, indicating a minor average systematic variability. After adjustment for age, gender, height, smoking status, pack-years of smoking, and degree of dyspnea, the scoring degree of radiographic abnormalities was significantly and negatively associated with absolute and percent predicted values of FVC: -0.07 (CI:95%, -0.01 to -0.04); -2.48 (CI:95%, -3.45 to -1.50); and FEV1 -0.07 (CI:95%, -0.10 to -0.05); -2.92 (CI:95%, -3.87 to -1.97) respectively, in the patients studied. Conclusion The extent of radiographic abnormalities, as evaluated through our novel scoring system, was inversely associated with spirometric values, and

  2. Retinal detachment in hemolysis, elevated liver enzymes, and low platelet count (HELLP) syndrome: Color vision abnormality as the first and predominant manifestation.

    PubMed

    Morisawa, Hiroyuki; Makino, Shinji; Takahashi, Hironori; Sorita, Mari; Matsubara, Shigeki

    2015-11-01

    Serous retinal detachment is sometimes caused by hypertensive disorders in pregnancy and its associated conditions, in which the predominant eye symptoms are blurred vision, distorted vision, and reduced visual acuity. To our best knowledge, this is the first report of a puerperal woman with hemolysis, elevated liver enzymes, and low platelet count (HELLP) syndrome in whom color vision abnormality was the first and predominant manifestation of serous retinal detachment. At 32 weeks of gestation, the 34-year-old Japanese woman underwent cesarean section due to HELLP syndrome. She complained of color vision abnormality on day 1 post-partum and ophthalmological examination revealed serous retinal detachment of both eyes. The visual acuity was preserved. With supportive therapy, her color vision abnormality gradually ameliorated and retinal detachment completely resolved on day 34 post-partum without any sequelae. Obstetricians should be aware that color vision abnormality can be the first and predominant symptom of HELLP-related serous retinal detachment. © 2015 Japan Society of Obstetrics and Gynecology.

  3. Dysfunctional visual word form processing in progressive alexia

    PubMed Central

    Rising, Kindle; Stib, Matthew T.; Rapcsak, Steven Z.; Beeson, Pélagie M.

    2013-01-01

    Progressive alexia is an acquired reading deficit caused by degeneration of brain regions that are essential for written word processing. Functional imaging studies have shown that early processing of the visual word form depends on a hierarchical posterior-to-anterior processing stream in occipito-temporal cortex, whereby successive areas code increasingly larger and more complex perceptual attributes of the letter string. A region located in the left lateral occipito-temporal sulcus and adjacent fusiform gyrus shows maximal selectivity for words and has been dubbed the ‘visual word form area’. We studied two patients with progressive alexia in order to determine whether their reading deficits were associated with structural and/or functional abnormalities in this visual word form system. Voxel-based morphometry showed left-lateralized occipito-temporal atrophy in both patients, very mild in one, but moderate to severe in the other. The two patients, along with 10 control subjects, were scanned with functional magnetic resonance imaging as they viewed rapidly presented words, false font strings, or a fixation crosshair. This paradigm was optimized to reliably map brain regions involved in orthographic processing in individual subjects. All 10 control subjects showed a posterior-to-anterior gradient of selectivity for words, and all 10 showed a functionally defined visual word form area in the left hemisphere that was activated for words relative to false font strings. In contrast, neither of the two patients with progressive alexia showed any evidence for a selectivity gradient or for word-specific activation of the visual word form area. The patient with mild atrophy showed normal responses to both words and false font strings in the posterior part of the visual word form system, but a failure to develop selectivity for words in the more anterior part of the system. In contrast, the patient with moderate to severe atrophy showed minimal activation of any part

  4. Dysfunctional visual word form processing in progressive alexia.

    PubMed

    Wilson, Stephen M; Rising, Kindle; Stib, Matthew T; Rapcsak, Steven Z; Beeson, Pélagie M

    2013-04-01

    Progressive alexia is an acquired reading deficit caused by degeneration of brain regions that are essential for written word processing. Functional imaging studies have shown that early processing of the visual word form depends on a hierarchical posterior-to-anterior processing stream in occipito-temporal cortex, whereby successive areas code increasingly larger and more complex perceptual attributes of the letter string. A region located in the left lateral occipito-temporal sulcus and adjacent fusiform gyrus shows maximal selectivity for words and has been dubbed the 'visual word form area'. We studied two patients with progressive alexia in order to determine whether their reading deficits were associated with structural and/or functional abnormalities in this visual word form system. Voxel-based morphometry showed left-lateralized occipito-temporal atrophy in both patients, very mild in one, but moderate to severe in the other. The two patients, along with 10 control subjects, were scanned with functional magnetic resonance imaging as they viewed rapidly presented words, false font strings, or a fixation crosshair. This paradigm was optimized to reliably map brain regions involved in orthographic processing in individual subjects. All 10 control subjects showed a posterior-to-anterior gradient of selectivity for words, and all 10 showed a functionally defined visual word form area in the left hemisphere that was activated for words relative to false font strings. In contrast, neither of the two patients with progressive alexia showed any evidence for a selectivity gradient or for word-specific activation of the visual word form area. The patient with mild atrophy showed normal responses to both words and false font strings in the posterior part of the visual word form system, but a failure to develop selectivity for words in the more anterior part of the system. In contrast, the patient with moderate to severe atrophy showed minimal activation of any part of

  5. Mastering algebra retrains the visual system to perceive hierarchical structure in equations.

    PubMed

    Marghetis, Tyler; Landy, David; Goldstone, Robert L

    2016-01-01

    Formal mathematics is a paragon of abstractness. It thus seems natural to assume that the mathematical expert should rely more on symbolic or conceptual processes, and less on perception and action. We argue instead that mathematical proficiency relies on perceptual systems that have been retrained to implement mathematical skills. Specifically, we investigated whether the visual system-in particular, object-based attention-is retrained so that parsing algebraic expressions and evaluating algebraic validity are accomplished by visual processing. Object-based attention occurs when the visual system organizes the world into discrete objects, which then guide the deployment of attention. One classic signature of object-based attention is better perceptual discrimination within, rather than between, visual objects. The current study reports that object-based attention occurs not only for simple shapes but also for symbolic mathematical elements within algebraic expressions-but only among individuals who have mastered the hierarchical syntax of algebra. Moreover, among these individuals, increased object-based attention within algebraic expressions is associated with a better ability to evaluate algebraic validity. These results suggest that, in mastering the rules of algebra, people retrain their visual system to represent and evaluate abstract mathematical structure. We thus argue that algebraic expertise involves the regimentation and reuse of evolutionarily ancient perceptual processes. Our findings implicate the visual system as central to learning and reasoning in mathematics, leading us to favor educational approaches to mathematics and related STEM fields that encourage students to adapt, not abandon, their use of perception.

  6. Art, illusion and the visual system.

    PubMed

    Livingstone, M S

    1988-01-01

    The verve of op art, the serenity of a pointillist painting and the 3-D puzzlement of an Escher print derive from the interplay of the art with the anatomy of the visual system. Color, shape and movement are each processed separately by different structures in the eye and brain and then are combined to produce the experience we call perception.

  7. Conceptual design study for an advanced cab and visual system, volume 1

    NASA Technical Reports Server (NTRS)

    Rue, R. J.; Cyrus, M. L.; Garnett, T. A.; Nachbor, J. W.; Seery, J. A.; Starr, R. L.

    1980-01-01

    A conceptual design study was conducted to define requirements for an advanced cab and visual system. The rotorcraft system integration simulator is for engineering studies in the area of mission associated vehicle handling qualities. Principally a technology survey and assessment of existing and proposed simulator visual display systems, image generation systems, modular cab designs, and simulator control station designs were performed and are discussed. State of the art survey data were used to synthesize a set of preliminary visual display system concepts of which five candidate display configurations were selected for further evaluation. Basic display concepts incorporated in these configurations included: real image projection, using either periscopes, fiber optic bundles, or scanned laser optics; and virtual imaging with helmet mounted displays. These display concepts were integrated in the study with a simulator cab concept employing a modular base for aircraft controls, crew seating, and instrumentation (or other) displays. A simple concept to induce vibration in the various modules was developed and is described. Results of evaluations and trade offs related to the candidate system concepts are given, along with a suggested weighting scheme for numerically comparing visual system performance characteristics.

  8. European dental students' opinions about visual and digital tooth colour determination systems.

    PubMed

    Dozic, Alma; Kharbanda, Aron K; Kamell, Hassib; Brand, Henk S

    2011-12-01

    The aim of the study was to investigate students' opinion about visual and digital tooth colour determination education at different European dental schools. A cross-sectional web-based survey was created, containing nine dichotomous, multiple choice and 5-point Likert scale questions. The questionnaire was distributed amongst students of 40 European dental schools. Seven hundred and ninety-nine completed questionnaires from students of 15 dental schools were analysed statistically. Vitapan Classical and Vitapan 3D-Master are the most frequently used visual determination systems at European dental schools. Most students responded with "neutral" regarding whether they find it easy to identify the colour of teeth with a visual determination system (range 2.8-3.6). A minority of the dental students had received education in digital imaging systems (2-47%). The Easyshade was the most frequently mentioned digital system. The majority of the students who did not receive education on digital systems would like to see this topic added to the curriculum (77-100%). The dental students who had worked with both methods found it significantly easier to determine tooth colour with a digital system than with a visual system (mean score 3.5 ± 0.8 vs. 3.0 ± 0.8). Tooth colour determination programmes show a considerable variation across European dental schools. Based upon the outcomes of this study, students prefer digital imaging systems over visual systems, and like to have (more) education about digital tooth colour imaging. Copyright © 2011 Elsevier Ltd. All rights reserved.

  9. Replacement of the Faces subtest by Visual Reproductions within Wechsler Memory Scale-Third Edition (WMS-III) visual memory indexes: implications for discrepancy analysis.

    PubMed

    Hawkins, Keith A; Tulsky, David S

    2004-06-01

    Within discrepancy analysis differences between scores are examined for abnormality. Although larger differences are generally associated with rising impairment probabilities, the relationship between discrepancy size and abnormality varies across score pairs in relation to the correlation between the contrasted scores in normal subjects. Examinee ability level also affects the size of discrepancies observed normally. Wechsler Memory Scale-Third Edition (WMS-III) visual index scores correlate only modestly with other Wechsler Adult Intelligence Scale-Third Edition (WAIS-III) and WMS-III index scores; consequently, differences between these scores and others have to be very large before they become unusual, especially for subjects of higher intelligence. The substitution of the Faces subtest by Visual Reproductions within visual memory indexes formed by the combination of WMS-III visual subtests (creating immediate recall, delayed recall, and combined immediate and delayed index scores) results in higher correlation coefficients, and a decline in the discrepancy size required to surpass base rate thresholds for probable impairment. This gain appears not to occur at the cost of a diminished sensitivity to diverse pathologies. New WMS-III discrepancy base rate data are supplied to complement those currently available to clinicians.

  10. An efficient abnormal cervical cell detection system based on multi-instance extreme learning machine

    NASA Astrophysics Data System (ADS)

    Zhao, Lili; Yin, Jianping; Yuan, Lihuan; Liu, Qiang; Li, Kuan; Qiu, Minghui

    2017-07-01

    Automatic detection of abnormal cells from cervical smear images is extremely demanded in annual diagnosis of women's cervical cancer. For this medical cell recognition problem, there are three different feature sections, namely cytology morphology, nuclear chromatin pathology and region intensity. The challenges of this problem come from feature combination s and classification accurately and efficiently. Thus, we propose an efficient abnormal cervical cell detection system based on multi-instance extreme learning machine (MI-ELM) to deal with above two questions in one unified framework. MI-ELM is one of the most promising supervised learning classifiers which can deal with several feature sections and realistic classification problems analytically. Experiment results over Herlev dataset demonstrate that the proposed method outperforms three traditional methods for two-class classification in terms of well accuracy and less time.

  11. Sensory system plasticity in a visually specialized, nocturnal spider.

    PubMed

    Stafstrom, Jay A; Michalik, Peter; Hebets, Eileen A

    2017-04-21

    The interplay between an animal's environmental niche and its behavior can influence the evolutionary form and function of its sensory systems. While intraspecific variation in sensory systems has been documented across distant taxa, fewer studies have investigated how changes in behavior might relate to plasticity in sensory systems across developmental time. To investigate the relationships among behavior, peripheral sensory structures, and central processing regions in the brain, we take advantage of a dramatic within-species shift of behavior in a nocturnal, net-casting spider (Deinopis spinosa), where males cease visually-mediated foraging upon maturation. We compared eye diameters and brain region volumes across sex and life stage, the latter through micro-computed X-ray tomography. We show that mature males possess altered peripheral visual morphology when compared to their juvenile counterparts, as well as juvenile and mature females. Matching peripheral sensory structure modifications, we uncovered differences in relative investment in both lower-order and higher-order processing regions in the brain responsible for visual processing. Our study provides evidence for sensory system plasticity when individuals dramatically change behavior across life stages, uncovering new avenues of inquiry focusing on altered reliance of specific sensory information when entering a new behavioral niche.

  12. Visual Behaviors and Adaptations Associated with Cortical and Ocular Impairment in Children.

    ERIC Educational Resources Information Center

    Jan, J. E.; Groenveld, M.

    1993-01-01

    This article shows the usefulness of understanding visual behaviors in the diagnosis of various types of visual impairments that are due to ocular and cortical disorders. Behaviors discussed include nystagmus, ocular motor dyspraxia, head position, close viewing, field loss adaptations, mannerisms, photophobia, and abnormal color perception. (JDD)

  13. Blindsight and Unconscious Vision: What They Teach Us about the Human Visual System

    PubMed Central

    Ajina, Sara; Bridge, Holly

    2017-01-01

    Damage to the primary visual cortex removes the major input from the eyes to the brain, causing significant visual loss as patients are unable to perceive the side of the world contralateral to the damage. Some patients, however, retain the ability to detect visual information within this blind region; this is known as blindsight. By studying the visual pathways that underlie this residual vision in patients, we can uncover additional aspects of the human visual system that likely contribute to normal visual function but cannot be revealed under physiological conditions. In this review, we discuss the residual abilities and neural activity that have been described in blindsight and the implications of these findings for understanding the intact system. PMID:27777337

  14. Dysflective cones: Visual function and cone reflectivity in long-term follow-up of acute bilateral foveolitis.

    PubMed

    Tu, Joanna H; Foote, Katharina G; Lujan, Brandon J; Ratnam, Kavitha; Qin, Jia; Gorin, Michael B; Cunningham, Emmett T; Tuten, William S; Duncan, Jacque L; Roorda, Austin

    2017-09-01

    Confocal adaptive optics scanning laser ophthalmoscope (AOSLO) images provide a sensitive measure of cone structure. However, the relationship between structural findings of diminished cone reflectivity and visual function is unclear. We used fundus-referenced testing to evaluate visual function in regions of apparent cone loss identified using confocal AOSLO images. A patient diagnosed with acute bilateral foveolitis had spectral-domain optical coherence tomography (SD-OCT) (Spectralis HRA + OCT system [Heidelberg Engineering, Vista, CA, USA]) images indicating focal loss of the inner segment-outer segment junction band with an intact, but hyper-reflective, external limiting membrane. Five years after symptom onset, visual acuity had improved from 20/80 to 20/25, but the retinal appearance remained unchanged compared to 3 months after symptoms began. We performed structural assessments using SD-OCT, directional OCT (non-standard use of a prototype on loan from Carl Zeiss Meditec) and AOSLO (custom-built system). We also administered fundus-referenced functional tests in the region of apparent cone loss, including analysis of preferred retinal locus (PRL), AOSLO acuity, and microperimetry with tracking SLO (TSLO) (prototype system). To determine AOSLO-corrected visual acuity, the scanning laser was modulated with a tumbling E consistent with 20/30 visual acuity. Visual sensitivity was assessed in and around the lesion using TSLO microperimetry. Complete eye examination, including standard measures of best-corrected visual acuity, visual field tests, color fundus photos, and fundus auto-fluorescence were also performed. Despite a lack of visible cone profiles in the foveal lesion, fundus-referenced vision testing demonstrated visual function within the lesion consistent with cone function. The PRL was within the lesion of apparent cone loss at the fovea. AOSLO visual acuity tests were abnormal, but measurable: for trials in which the stimulus remained completely

  15. Inter-Rater Reliability for Speech-Language Therapists' Judgement of Oesophageal Abnormality during Oesophageal Visualization

    ERIC Educational Resources Information Center

    Miles, Anna

    2017-01-01

    Background: Oesophageal abnormalities are common findings in a speech-language therapy videofluoroscopy clinic. Fluoroscopic screening involving oropharynx alone fails to identify these patients. Oesophageal screening as an adjunct to videofluoroscopy is gaining popularity. Yet currently, little is known about the reliability of speech and…

  16. Visual function at 11 years of age in preterm-born children with and without fetal brain sparing.

    PubMed

    Kok, Joke H; Prick, Liesbeth; Merckel, Elly; Everhard, Yolande; Verkerk, Gijs J Q; Scherjon, Sicco A

    2007-06-01

    We have demonstrated earlier an accelerated maturation of the visual evoked potential in the first year of life in preterm infants with antenatal brain sparing. We have now assessed visual functioning at 11 years of age in the same cohort and compared the groups with and without brain sparing. One hundred sixteen survivors included in a study on the outcome of preterm infants born at <33 weeks' gestation with and without fetal brain sparing and admitted to the NICU were followed extensively. Ninety-eight infants (85%) were again assessed at 11 years of age. Data were available for fetal Doppler measurements indicating brain sparing, neonatal cerebral ultrasound scanning, and developmental outcome in the first 5 years. Mean birth weight was 1303 g; mean gestational age was 29.8 weeks. The infants were divided into 2 groups with and without brain sparing. Visual functioning was estimated by measuring visual acuity, visual fields, eye position, and binocular function and by visual motor tests. Six percent of the children were found to have a visual acuity of <0.8, 12% had strabismus, and 14% to 46% showed abnormal results on the visual motor tests. No statistical differences were found between the 2 groups. However, children with severe cerebral ultrasound diagnoses in the neonatal period were found to have significantly more abnormalities on visual functioning and lower scores on visual motor tests than children without these morbidities. Children with fetal brain sparing do not demonstrate a different development of their visual functioning at late school age. However, an abnormal cerebral ultrasound in the neonatal period is associated with impaired visual function in later life.

  17. A versatile stereoscopic visual display system for vestibular and oculomotor research.

    PubMed

    Kramer, P D; Roberts, D C; Shelhamer, M; Zee, D S

    1998-01-01

    Testing of the vestibular system requires a vestibular stimulus (motion) and/or a visual stimulus. We have developed a versatile, low cost, stereoscopic visual display system, using "virtual reality" (VR) technology. The display system can produce images for each eye that correspond to targets at any virtual distance relative to the subject, and so require the appropriate ocular vergence. We elicited smooth pursuit, "stare" optokinetic nystagmus (OKN) and after-nystagmus (OKAN), vergence for targets at various distances, and short-term adaptation of the vestibulo-ocular reflex (VOR), using both conventional methods and the stereoscopic display. Pursuit, OKN, and OKAN were comparable with both methods. When used with a vestibular stimulus, VR induced appropriate adaptive changes of the phase and gain of the angular VOR. In addition, using the VR display system and a human linear acceleration sled, we adapted the phase of the linear VOR. The VR-based stimulus system not only offers an alternative to more cumbersome means of stimulating the visual system in vestibular experiments, it also can produce visual stimuli that would otherwise be impractical or impossible. Our techniques provide images without the latencies encountered in most VR systems. Its inherent versatility allows it to be useful in several different types of experiments, and because it is software driven it can be quickly adapted to provide a new stimulus. These two factors allow VR to provide considerable savings in time and money, as well as flexibility in developing experimental paradigms.

  18. An indoor navigation system for the visually impaired.

    PubMed

    Guerrero, Luis A; Vasquez, Francisco; Ochoa, Sergio F

    2012-01-01

    Navigation in indoor environments is highly challenging for the severely visually impaired, particularly in spaces visited for the first time. Several solutions have been proposed to deal with this challenge. Although some of them have shown to be useful in real scenarios, they involve an important deployment effort or use artifacts that are not natural for blind users. This paper presents an indoor navigation system that was designed taking into consideration usability as the quality requirement to be maximized. This solution enables one to identify the position of a person and calculates the velocity and direction of his movements. Using this information, the system determines the user's trajectory, locates possible obstacles in that route, and offers navigation information to the user. The solution has been evaluated using two experimental scenarios. Although the results are still not enough to provide strong conclusions, they indicate that the system is suitable to guide visually impaired people through an unknown built environment.

  19. An Indoor Navigation System for the Visually Impaired

    PubMed Central

    Guerrero, Luis A.; Vasquez, Francisco; Ochoa, Sergio F.

    2012-01-01

    Navigation in indoor environments is highly challenging for the severely visually impaired, particularly in spaces visited for the first time. Several solutions have been proposed to deal with this challenge. Although some of them have shown to be useful in real scenarios, they involve an important deployment effort or use artifacts that are not natural for blind users. This paper presents an indoor navigation system that was designed taking into consideration usability as the quality requirement to be maximized. This solution enables one to identify the position of a person and calculates the velocity and direction of his movements. Using this information, the system determines the user's trajectory, locates possible obstacles in that route, and offers navigation information to the user. The solution has been evaluated using two experimental scenarios. Although the results are still not enough to provide strong conclusions, they indicate that the system is suitable to guide visually impaired people through an unknown built environment. PMID:22969398

  20. Eye movement-invariant representations in the human visual system.

    PubMed

    Nishimoto, Shinji; Huth, Alexander G; Bilenko, Natalia Y; Gallant, Jack L

    2017-01-01

    During natural vision, humans make frequent eye movements but perceive a stable visual world. It is therefore likely that the human visual system contains representations of the visual world that are invariant to eye movements. Here we present an experiment designed to identify visual areas that might contain eye-movement-invariant representations. We used functional MRI to record brain activity from four human subjects who watched natural movies. In one condition subjects were required to fixate steadily, and in the other they were allowed to freely make voluntary eye movements. The movies used in each condition were identical. We reasoned that the brain activity recorded in a visual area that is invariant to eye movement should be similar under fixation and free viewing conditions. In contrast, activity in a visual area that is sensitive to eye movement should differ between fixation and free viewing. We therefore measured the similarity of brain activity across repeated presentations of the same movie within the fixation condition, and separately between the fixation and free viewing conditions. The ratio of these measures was used to determine which brain areas are most likely to contain eye movement-invariant representations. We found that voxels located in early visual areas are strongly affected by eye movements, while voxels in ventral temporal areas are only weakly affected by eye movements. These results suggest that the ventral temporal visual areas contain a stable representation of the visual world that is invariant to eye movements made during natural vision.

  1. Perceived functional impact of abnormal facial appearance.

    PubMed

    Rankin, Marlene; Borah, Gregory L

    2003-06-01

    Functional facial deformities are usually described as those that impair respiration, eating, hearing, or speech. Yet facial scars and cutaneous deformities have a significant negative effect on social functionality that has been poorly documented in the scientific literature. Insurance companies are declining payments for reconstructive surgical procedures for facial deformities caused by congenital disabilities and after cancer or trauma operations that do not affect mechanical facial activity. The purpose of this study was to establish a large, sample-based evaluation of the perceived social functioning, interpersonal characteristics, and employability indices for a range of facial appearances (normal and abnormal). Adult volunteer evaluators (n = 210) provided their subjective perceptions based on facial physical appearance, and an analysis of the consequences of facial deformity on parameters of preferential treatment was performed. A two-group comparative research design rated the differences among 10 examples of digitally altered facial photographs of actual patients among various age and ethnic groups with "normal" and "abnormal" congenital deformities or posttrauma scars. Photographs of adult patients with observable congenital and posttraumatic deformities (abnormal) were digitally retouched to eliminate the stigmatic defects (normal). The normal and abnormal photographs of identical patients were evaluated by the large sample study group on nine parameters of social functioning, such as honesty, employability, attractiveness, and effectiveness, using a visual analogue rating scale. Patients with abnormal facial characteristics were rated as significantly less honest (p = 0.007), less employable (p = 0.001), less trustworthy (p = 0.01), less optimistic (p = 0.001), less effective (p = 0.02), less capable (p = 0.002), less intelligent (p = 0.03), less popular (p = 0.001), and less attractive (p = 0.001) than were the same patients with normal facial

  2. The visual information system

    Treesearch

    Merlyn J. Paulson

    1979-01-01

    This paper outlines a project level process (V.I.S.) which utilizes very accurate and flexible computer algorithms in combination with contemporary site analysis and design techniques for visual evaluation, design and management. The process provides logical direction and connecting bridges through problem identification, information collection and verification, visual...

  3. A General Provincial Situation Visualization System Based on iPhone Operating System of Shandong Province

    NASA Astrophysics Data System (ADS)

    Ye, Z.; Xiang, H.

    2014-04-01

    The paper discusses the basic principles and the problem solutions during the design and implementation of the mobile GIS system, and base on the research result, we developed the General Provincial Situation Visualization System Based on iOS of Shandong Province. The system is developed in the Objective-C programming language, and use the ArcGIS Runtime SDK for IOS as the development tool to call the "World-map Shandong" services to implement the development of the General Provincial Situation Visualization System Based on iOS devices. The system is currently available for download in the Appstore and is chosen as the typical application case of ESRI China ArcGIS API for iOS.

  4. Abnormalities of fixation, saccade and pursuit in posterior cortical atrophy.

    PubMed

    Shakespeare, Timothy J; Kaski, Diego; Yong, Keir X X; Paterson, Ross W; Slattery, Catherine F; Ryan, Natalie S; Schott, Jonathan M; Crutch, Sebastian J

    2015-07-01

    The clinico-neuroradiological syndrome posterior cortical atrophy is the cardinal 'visual dementia' and most common atypical Alzheimer's disease phenotype, offering insights into mechanisms underlying clinical heterogeneity, pathological propagation and basic visual phenomena (e.g. visual crowding). Given the extensive attention paid to patients' (higher order) perceptual function, it is surprising that there have been no systematic analyses of basic oculomotor function in this population. Here 20 patients with posterior cortical atrophy, 17 patients with typical Alzheimer's disease and 22 healthy controls completed tests of fixation, saccade (including fixation/target gap and overlap conditions) and smooth pursuit eye movements using an infrared pupil-tracking system. Participants underwent detailed neuropsychological and neurological examinations, with a proportion also undertaking brain imaging and analysis of molecular pathology. In contrast to informal clinical evaluations of oculomotor dysfunction frequency (previous studies: 38%, current clinical examination: 33%), detailed eyetracking investigations revealed eye movement abnormalities in 80% of patients with posterior cortical atrophy (compared to 17% typical Alzheimer's disease, 5% controls). The greatest differences between posterior cortical atrophy and typical Alzheimer's disease were seen in saccadic performance. Patients with posterior cortical atrophy made significantly shorter saccades especially for distant targets. They also exhibited a significant exacerbation of the normal gap/overlap effect, consistent with 'sticky fixation'. Time to reach saccadic targets was significantly associated with parietal and occipital cortical thickness measures. On fixation stability tasks, patients with typical Alzheimer's disease showed more square wave jerks whose frequency was associated with lower cerebellar grey matter volume, while patients with posterior cortical atrophy showed large saccadic intrusions

  5. Abnormalities of fixation, saccade and pursuit in posterior cortical atrophy

    PubMed Central

    Kaski, Diego; Yong, Keir X. X.; Paterson, Ross W.; Slattery, Catherine F.; Ryan, Natalie S.; Schott, Jonathan M.; Crutch, Sebastian J.

    2015-01-01

    The clinico-neuroradiological syndrome posterior cortical atrophy is the cardinal ‘visual dementia’ and most common atypical Alzheimer’s disease phenotype, offering insights into mechanisms underlying clinical heterogeneity, pathological propagation and basic visual phenomena (e.g. visual crowding). Given the extensive attention paid to patients’ (higher order) perceptual function, it is surprising that there have been no systematic analyses of basic oculomotor function in this population. Here 20 patients with posterior cortical atrophy, 17 patients with typical Alzheimer’s disease and 22 healthy controls completed tests of fixation, saccade (including fixation/target gap and overlap conditions) and smooth pursuit eye movements using an infrared pupil-tracking system. Participants underwent detailed neuropsychological and neurological examinations, with a proportion also undertaking brain imaging and analysis of molecular pathology. In contrast to informal clinical evaluations of oculomotor dysfunction frequency (previous studies: 38%, current clinical examination: 33%), detailed eyetracking investigations revealed eye movement abnormalities in 80% of patients with posterior cortical atrophy (compared to 17% typical Alzheimer’s disease, 5% controls). The greatest differences between posterior cortical atrophy and typical Alzheimer’s disease were seen in saccadic performance. Patients with posterior cortical atrophy made significantly shorter saccades especially for distant targets. They also exhibited a significant exacerbation of the normal gap/overlap effect, consistent with ‘sticky fixation’. Time to reach saccadic targets was significantly associated with parietal and occipital cortical thickness measures. On fixation stability tasks, patients with typical Alzheimer’s disease showed more square wave jerks whose frequency was associated with lower cerebellar grey matter volume, while patients with posterior cortical atrophy showed large

  6. Neonatal Brain Abnormalities and Memory and Learning Outcomes at 7 Years in Children Born Very Preterm

    PubMed Central

    Omizzolo, Cristina; Scratch, Shannon E; Stargatt, Robyn; Kidokoro, Hiroyuki; Thompson, Deanne K; Lee, Katherine J; Cheong, Jeanie; Neil, Jeffrey; Inder, Terrie E; Doyle, Lex W; Anderson, Peter J

    2014-01-01

    Using prospective longitudinal data from 198 very preterm and 70 full term children, this study characterised the memory and learning abilities of very preterm children at 7 years of age in both verbal and visual domains. The relationship between the extent of brain abnormalities on neonatal magnetic resonance imaging (MRI) and memory and learning outcomes at 7 years of age in very preterm children was also investigated. Neonatal MRI scans were qualitatively assessed for global, white-matter, cortical grey-matter, deep grey-matter, and cerebellar abnormalities. Very preterm children performed less well on measures of immediate memory, working memory, long-term memory, and learning compared with term born controls. Neonatal brain abnormalities, and in particular deep grey matter abnormality, were associated with poorer memory and learning performance at 7 years in very preterm children, especially global, white-matter, grey-matter and cerebellar abnormalities. Findings support the importance of cerebral neonatal pathology for predicting later memory and learning function. PMID:23805915

  7. Color vision abnormality as an initial presentation of the complete type of congenital stationary night blindness.

    PubMed

    Tan, Xue; Aoki, Aya; Yanagi, Yasuo

    2013-01-01

    Patients with the complete form of congenital stationary night blindness (CSNB) often have reduced visual acuity, myopia, impaired night vision, and sometimes nystagmus and strabismus, however, they seldom complain of color vision abnormality. A 17-year-old male who was at technical school showed abnormalities in the color perception test for employment, and was referred to our hospital for a detailed examination. He had no family history of color vision deficiency and no other symptoms. During the initial examination, his best-corrected visual acuity was 1.2 in both eyes. His fundus showed no abnormalities except for somewhat yellowish reflex in the fovea of both eyes. Electroretinogram (ERG) showed a good response in cone ERG and 30 Hz flicker ERG, however, the bright flash, mixed rod and cone ERG showed a negative type with a reduced b-wave (positive deflection). There was no response in the rod ERG, either. From the findings of the typical ERG, the patient was diagnosed with complete congenital stationary night blindness. This case underscores the importance of ERG in order to diagnose the cause of a color vision anomaly.

  8. Complex Digital Visual Systems

    ERIC Educational Resources Information Center

    Sweeny, Robert W.

    2013-01-01

    This article identifies possibilities for data visualization as art educational research practice. The author presents an analysis of the relationship between works of art and digital visual culture, employing aspects of network analysis drawn from the work of Barabási, Newman, and Watts (2006) and Castells (1994). Describing complex network…

  9. Optimizing text for an individual's visual system: The contribution of visual crowding to reading difficulties.

    PubMed

    Joo, Sung Jun; White, Alex L; Strodtman, Douglas J; Yeatman, Jason D

    2018-06-01

    Reading is a complex process that involves low-level visual processing, phonological processing, and higher-level semantic processing. Given that skilled reading requires integrating information among these different systems, it is likely that reading difficulty-known as dyslexia-can emerge from impairments at any stage of the reading circuitry. To understand contributing factors to reading difficulties within individuals, it is necessary to diagnose the function of each component of the reading circuitry. Here, we investigated whether adults with dyslexia who have impairments in visual processing respond to a visual manipulation specifically targeting their impairment. We collected psychophysical measures of visual crowding and tested how each individual's reading performance was affected by increased text-spacing, a manipulation designed to alleviate severe crowding. Critically, we identified a sub-group of individuals with dyslexia showing elevated crowding and found that these individuals read faster when text was rendered with increased letter-, word- and line-spacing. Our findings point to a subtype of dyslexia involving elevated crowding and demonstrate that individuals benefit from interventions personalized to their specific impairments. Copyright © 2018 Elsevier Ltd. All rights reserved.

  10. Comprehensive visual field test & diagnosis system in support of astronaut health and performance

    NASA Astrophysics Data System (ADS)

    Fink, Wolfgang; Clark, Jonathan B.; Reisman, Garrett E.; Tarbell, Mark A.

    Long duration spaceflight, permanent human presence on the Moon, and future human missions to Mars will require autonomous medical care to address both expected and unexpected risks. An integrated non-invasive visual field test & diagnosis system is presented for the identification, characterization, and automated classification of visual field defects caused by the spaceflight environment. This system will support the onboard medical provider and astronauts on space missions with an innovative, non-invasive, accurate, sensitive, and fast visual field test. It includes a database for examination data, and a software package for automated visual field analysis and diagnosis. The system will be used to detect and diagnose conditions affecting the visual field, while in space and on Earth, permitting the timely application of therapeutic countermeasures before astronaut health or performance are impaired. State-of-the-art perimetry devices are bulky, thereby precluding application in a spaceflight setting. In contrast, the visual field test & diagnosis system requires only a touchscreen-equipped computer or touchpad device, which may already be in use for other purposes (i.e., no additional payload), and custom software. The system has application in routine astronaut assessment (Clinical Status Exam), pre-, in-, and post-flight monitoring, and astronaut selection. It is deployable in operational space environments, such as aboard the International Space Station or during future missions to or permanent presence on the Moon and Mars.

  11. A Global System for Transportation Simulation and Visualization in Emergency Evacuation Scenarios

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Lu, Wei; Liu, Cheng; Thomas, Neil

    2015-01-01

    Simulation-based studies are frequently used for evacuation planning and decision making processes. Given the transportation systems complexity and data availability, most evacuation simulation models focus on certain geographic areas. With routine improvement of OpenStreetMap road networks and LandScanTM global population distribution data, we present WWEE, a uniform system for world-wide emergency evacuation simulations. WWEE uses unified data structure for simulation inputs. It also integrates a super-node trip distribution model as the default simulation parameter to improve the system computational performance. Two levels of visualization tools are implemented for evacuation performance analysis, including link-based macroscopic visualization and vehicle-based microscopic visualization. Formore » left-hand and right-hand traffic patterns in different countries, the authors propose a mirror technique to experiment with both scenarios without significantly changing traffic simulation models. Ten cities in US, Europe, Middle East, and Asia are modeled for demonstration. With default traffic simulation models for fast and easy-to-use evacuation estimation and visualization, WWEE also retains the capability of interactive operation for users to adopt customized traffic simulation models. For the first time, WWEE provides a unified platform for global evacuation researchers to estimate and visualize their strategies performance of transportation systems under evacuation scenarios.« less

  12. Reading impairment in schizophrenia: dysconnectivity within the visual system.

    PubMed

    Vinckier, Fabien; Cohen, Laurent; Oppenheim, Catherine; Salvador, Alexandre; Picard, Hernan; Amado, Isabelle; Krebs, Marie-Odile; Gaillard, Raphaël

    2014-01-01

    Patients with schizophrenia suffer from perceptual visual deficits. It remains unclear whether those deficits result from an isolated impairment of a localized brain process or from a more diffuse long-range dysconnectivity within the visual system. We aimed to explore, with a reading paradigm, the functioning of both ventral and dorsal visual pathways and their interaction in schizophrenia. Patients with schizophrenia and control subjects were studied using event-related functional MRI (fMRI) while reading words that were progressively degraded through word rotation or letter spacing. Reading intact or minimally degraded single words involves mainly the ventral visual pathway. Conversely, reading in non-optimal conditions involves both the ventral and the dorsal pathway. The reading paradigm thus allowed us to study the functioning of both pathways and their interaction. Behaviourally, patients with schizophrenia were selectively impaired at reading highly degraded words. While fMRI activation level was not different between patients and controls, functional connectivity between the ventral and dorsal visual pathways increased with word degradation in control subjects, but not in patients. Moreover, there was a negative correlation between the patients' behavioural sensitivity to stimulus degradation and dorso-ventral connectivity. This study suggests that perceptual visual deficits in schizophrenia could be related to dysconnectivity between dorsal and ventral visual pathways. © 2013 Published by Elsevier Ltd.

  13. A visual servo-based teleoperation robot system for closed diaphyseal fracture reduction.

    PubMed

    Li, Changsheng; Wang, Tianmiao; Hu, Lei; Zhang, Lihai; Du, Hailong; Zhao, Lu; Wang, Lifeng; Tang, Peifu

    2015-09-01

    Common fracture treatments include open reduction and intramedullary nailing technology. However, these methods have disadvantages such as intraoperative X-ray radiation, delayed union or nonunion and postoperative rotation. Robots provide a novel solution to the aforementioned problems while posing new challenges. Against this scientific background, we develop a visual servo-based teleoperation robot system. In this article, we present a robot system, analyze the visual servo-based control system in detail and develop path planning for fracture reduction, inverse kinematics, and output forces of the reduction mechanism. A series of experimental tests is conducted on a bone model and an animal bone. The experimental results demonstrate the feasibility of the robot system. The robot system uses preoperative computed tomography data to realize high precision and perform minimally invasive teleoperation for fracture reduction via the visual servo-based control system while protecting surgeons from radiation. © IMechE 2015.

  14. Visualizing Terrestrial and Aquatic Systems in 3D - in IEEE VisWeek 2014

    EPA Science Inventory

    The need for better visualization tools for environmental science is well documented, and the Visualization for Terrestrial and Aquatic Systems project (VISTAS) aims to both help scientists produce effective environmental science visualizations and to determine which visualizatio...

  15. Development of the Macro Command Editing Executive System for Factory Workers-Oriented Programless Visual Inspection System

    NASA Astrophysics Data System (ADS)

    Anezaki, Takashi; Wakitani, Kouichi; Nakamura, Masatoshi; Kubo, Hiroyasu

    Because visual inspection systems are difficult to tune, they create many problems for the kaizen process. This results in increased development costs and time to assure that the inspection systems function properly. In order to improve inspection system development, we designed an easy-tuning system called a “Program-less” visual inspection system. The ROI macro command which consisted of eight kinds of shape recognition macro commands and decision, operation, control commands was built. Furthermore, the macro command editing executive system was developed by the operation of only the GUI without editing source program. The validity of the ROI macro command was proved by the application of 488 places.

  16. A new system for quantitative evaluation of infant gaze capabilities in a wide visual field.

    PubMed

    Pratesi, Andrea; Cecchi, Francesca; Beani, Elena; Sgandurra, Giuseppina; Cioni, Giovanni; Laschi, Cecilia; Dario, Paolo

    2015-09-07

    The visual assessment of infants poses specific challenges: many techniques that are used on adults are based on the patient's response, and are not suitable for infants. Significant advances in the eye-tracking have made this assessment of infant visual capabilities easier, however, eye-tracking still requires the subject's collaboration, in most cases and thus limiting the application in infant research. Moreover, there is a lack of transferability to clinical practice, and thus it emerges the need for a new tool to measure the paradigms and explore the most common visual competences in a wide visual field. This work presents the design, development and preliminary testing of a new system for measuring infant's gaze in the wide visual field called CareToy C: CareToy for Clinics. The system is based on a commercial eye tracker (SmartEye) with six cameras running at 60 Hz, suitable for measuring an infant's gaze. In order to stimulate the infant visually and audibly, a mechanical structure has been designed to support five speakers and five screens at a specific distance (60 cm) and angle: one in the centre, two on the right-hand side and two on the left (at 30° and 60° respectively). Different tasks have been designed in order to evaluate the system capability to assess the infant's gaze movements during different conditions (such as gap, overlap or audio-visual paradigms). Nine healthy infants aged 4-10 months were assessed as they performed the visual tasks at random. We developed a system able to measure infant's gaze in a wide visual field covering a total visual range of ±60° from the centre with an intermediate evaluation at ±30°. Moreover, the same system, thanks to different integrated software, was able to provide different visual paradigms (as gap, overlap and audio-visual) assessing and comparing different visual and multisensory sub-competencies. The proposed system endowed the integration of a commercial eye-tracker into a purposive setup in

  17. Factors Related to Impaired Visual Orienting Behavior in Children with Intellectual Disabilities

    ERIC Educational Resources Information Center

    Boot, F. H.; Pel, J .J. M.; Evenhuis, H. M.; van der Steen, J.

    2012-01-01

    It is generally assumed that children with intellectual disabilities (ID) have an increased risk of impaired visual information processing due to brain damage or brain development disorder. So far little evidence has been presented to support this assumption. Abnormal visual orienting behavior is a sensitive tool to evaluate impaired visual…

  18. Feeling Abnormal: Simulation of Deviancy in Abnormal and Exceptionality Courses.

    ERIC Educational Resources Information Center

    Fernald, Charles D.

    1980-01-01

    Describes activity in which student in abnormal psychology and psychology of exceptional children classes personally experience being judged abnormal. The experience allows the students to remember relevant research, become sensitized to the feelings of individuals classified as deviant, and use caution in classifying individuals as abnormal.…

  19. Abnormal medial prefrontal cortex activity in heavy cannabis users during conscious emotional evaluation.

    PubMed

    Wesley, Michael J; Lile, Joshua A; Hanlon, Colleen A; Porrino, Linda J

    2016-03-01

    Long-term heavy cannabis users (cannabis users) who are not acutely intoxicated have diminished subconscious neural responsiveness to affective stimuli. This study sought to determine if abnormal processing extends to the conscious evaluation of emotional stimuli. Functional magnetic resonance imaging (fMRI) was used to examine brain activity as cannabis users (N = 16) and non-cannabis-using controls (N = 17) evaluated and categorized standardized International Affective Picture System (IAPS) stimuli. Individual judgments were used to isolate activity during the evaluation of emotional (i.e., emotional evaluation) or neutral (i.e., neutral evaluation) stimuli. Within- and between-group analyses were performed. Both groups judged the same stimuli as emotional and had activations in visual, midbrain, and middle cingulate cortices during emotional evaluation, relative to neutral. Within-group analyses also revealed amygdalar and inferior frontal gyrus activations in controls, but not cannabis users, and medial prefrontal cortex (mPFC) deactivations in cannabis users, but not controls, during emotional evaluation, relative to neutral. Between-group comparisons found that mPFC activity during positive and negative evaluation was significantly hypoactive in cannabis users, relative to controls. Abnormal neural processing of affective content extends to the level of consciousness in cannabis users. The hypoactive mPFC responses observed resembles the attenuated mPFC responses found during increased non-affective cognitive load in prior research. These findings suggest that abnormal mPFC singling in cannabis users during emotional evaluation might be associated with increased non-affective cognitive load.

  20. Abnormal Uterine Bleeding

    MedlinePlus

    ... abnormal uterine bleeding? Abnormal uterine bleeding is any heavy or unusual bleeding from the uterus (through your ... one symptom of abnormal uterine bleeding. Having extremely heavy bleeding during your period can also be considered ...

  1. Quantifying the abnormal hemodynamics of sickle cell anemia

    NASA Astrophysics Data System (ADS)

    Lei, Huan; Karniadakis, George

    2012-02-01

    Sickle red blood cells (SS-RBC) exhibit heterogeneous morphologies and abnormal hemodynamics in deoxygenated states. A multi-scale model for SS-RBC is developed based on the Dissipative Particle Dynamics (DPD) method. Different cell morphologies (sickle, granular, elongated shapes) typically observed in deoxygenated states are constructed and quantified by the Asphericity and Elliptical shape factors. The hemodynamics of SS-RBC suspensions is studied in both shear and pipe flow systems. The flow resistance obtained from both systems exhibits a larger value than the healthy blood flow due to the abnormal cell properties. Moreover, SS-RBCs exhibit abnormal adhesive interactions with both the vessel endothelium cells and the leukocytes. The effect of the abnormal adhesive interactions on the hemodynamics of sickle blood is investigated using the current model. It is found that both the SS-RBC - endothelium and the SS-RBC - leukocytes interactions, can potentially trigger the vicious ``sickling and entrapment'' cycles, resulting in vaso-occlusion phenomena widely observed in micro-circulation experiments.

  2. A simple infrared-augmented digital photography technique for detection of pupillary abnormalities.

    PubMed

    Shazly, Tarek A; Bonhomme, G R

    2015-03-01

    The purpose of the study was to describe a simple infrared photography technique to aid in the diagnosis and documentation of pupillary abnormalities. An unmodified 12-megapixel "point and shoot" digital camera was used to obtain binocular still photos and videos under different light conditions with near-infrared illuminating frames. The near-infrared light of 850 nm allows the capture of clear pupil images in both dim and bright light conditions. It also allows easy visualization of the pupil despite pigmented irides by augmenting the contrast between the iris and the pupil. The photos and videos obtained illustrated a variety of pupillary abnormalities using the aforementioned technique. This infrared-augmented photography technique supplements medical education, and aids in the more rapid detection, diagnosis, and documentation of a wide spectrum of pupillary abnormalities. Its portability and ease of use with minimal training complements the education of trainees and facilitates the establishment of difficult diagnoses.

  3. A reliable sewage quality abnormal event monitoring system.

    PubMed

    Li, Tianling; Winnel, Melissa; Lin, Hao; Panther, Jared; Liu, Chang; O'Halloran, Roger; Wang, Kewen; An, Taicheng; Wong, Po Keung; Zhang, Shanqing; Zhao, Huijun

    2017-09-15

    With closing water loop through purified recycled water, wastewater becomes a part of source water, requiring reliable wastewater quality monitoring system (WQMS) to manage wastewater source and mitigate potential health risks. However, the development of reliable WQMS is fatally constrained by severe contamination and biofouling of sensors due to the hostile analytical environment of wastewaters, especially raw sewages, that challenges the limit of existing sensing technologies. In this work, we report a technological solution to enable the development of WQMS for real-time abnormal event detection with high reliability and practicality. A vectored high flow hydrodynamic self-cleaning approach and a dual-sensor self-diagnostic concept are adopted for WQMS to effectively encounter vital sensor failing issues caused by contamination and biofouling and ensure the integrity of sensing data. The performance of the WQMS has been evaluated over a 3-year trial period at different sewage catchment sites across three Australian states. It has demonstrated that the developed WQMS is capable of continuously operating in raw sewage for a prolonged period up to 24 months without maintenance and failure, signifying the high reliability and practicality. The demonstrated WQMS capability to reliably acquire real-time wastewater quality information leaps forward the development of effective wastewater source management system. The reported self-cleaning and self-diagnostic concepts should be applicable to other online water quality monitoring systems, opening a new way to encounter the common reliability and stability issues caused by sensor contamination and biofouling. Copyright © 2017 Elsevier Ltd. All rights reserved.

  4. Visual gravitational motion and the vestibular system in humans

    PubMed Central

    Lacquaniti, Francesco; Bosco, Gianfranco; Indovina, Iole; La Scaleia, Barbara; Maffei, Vincenzo; Moscatelli, Alessandro; Zago, Myrka

    2013-01-01

    The visual system is poorly sensitive to arbitrary accelerations, but accurately detects the effects of gravity on a target motion. Here we review behavioral and neuroimaging data about the neural mechanisms for dealing with object motion and egomotion under gravity. The results from several experiments show that the visual estimates of a target motion under gravity depend on the combination of a prior of gravity effects with on-line visual signals on target position and velocity. These estimates are affected by vestibular inputs, and are encoded in a visual-vestibular network whose core regions lie within or around the Sylvian fissure, and are represented by the posterior insula/retroinsula/temporo-parietal junction. This network responds both to target motions coherent with gravity and to vestibular caloric stimulation in human fMRI studies. Transient inactivation of the temporo-parietal junction selectively disrupts the interception of targets accelerated by gravity. PMID:24421761

  5. Visual gravitational motion and the vestibular system in humans.

    PubMed

    Lacquaniti, Francesco; Bosco, Gianfranco; Indovina, Iole; La Scaleia, Barbara; Maffei, Vincenzo; Moscatelli, Alessandro; Zago, Myrka

    2013-12-26

    The visual system is poorly sensitive to arbitrary accelerations, but accurately detects the effects of gravity on a target motion. Here we review behavioral and neuroimaging data about the neural mechanisms for dealing with object motion and egomotion under gravity. The results from several experiments show that the visual estimates of a target motion under gravity depend on the combination of a prior of gravity effects with on-line visual signals on target position and velocity. These estimates are affected by vestibular inputs, and are encoded in a visual-vestibular network whose core regions lie within or around the Sylvian fissure, and are represented by the posterior insula/retroinsula/temporo-parietal junction. This network responds both to target motions coherent with gravity and to vestibular caloric stimulation in human fMRI studies. Transient inactivation of the temporo-parietal junction selectively disrupts the interception of targets accelerated by gravity.

  6. Abnormal Magnetic Field Effects on Electrogenerated Chemiluminescence

    NASA Astrophysics Data System (ADS)

    Pan, Haiping; Shen, Yan; Wang, Hongfeng; He, Lei; Hu, Bin

    2015-03-01

    We report abnormal magnetic field effects on electrogenerated chemiluminescence (MFEECL) based on triplet emission from the Ru(bpy)3Cl2-TPrA electrochemical system: the appearance of MFEECL after magnetic field ceases. In early studies the normal MFEECL have been observed from electrochemical systems during the application of magnetic field. Here, the abnormal MFEECL suggest that the activated charge-transfer [Ru(bpy)33+ … TPrA•] complexes may become magnetized in magnetic field and experience a long magnetic relaxation after removing magnetic field. Our analysis indicates that the magnetic relaxation can gradually increase the density of charge-transfer complexes within reaction region due to decayed magnetic interactions, leading to a positive component in the abnormal MFEECL. On the other hand, the magnetic relaxation facilitates an inverse conversion from triplets to singlets within charge-transfer complexes. The inverse triplet --> singlet conversion reduces the density of triplet light-emitting states through charge-transfer complexes and gives rise to a negative component in the abnormal MFEECL. The combination of positive and negative components can essentially lead to a non-monotonic profile in the abnormal MFEECL after ceasing magnetic field. Nevertheless, our experimental studies may reveal un-usual magnetic behaviors with long magnetic relaxation from the activated charge-transfer [Ru(bpy)33+ … TPrA•] complexes in solution at room temperature.

  7. Connectopathy in Autism Spectrum Disorders: A Review of Evidence from Visual Evoked Potentials and Diffusion Magnetic Resonance Imaging

    PubMed Central

    Yamasaki, Takao; Maekawa, Toshihiko; Fujita, Takako; Tobimatsu, Shozo

    2017-01-01

    Individuals with autism spectrum disorder (ASD) show superior performance in processing fine details; however, they often exhibit impairments of gestalt face, global motion perception, and visual attention as well as core social deficits. Increasing evidence has suggested that social deficits in ASD arise from abnormal functional and structural connectivities between and within distributed cortical networks that are recruited during social information processing. Because the human visual system is characterized by a set of parallel, hierarchical, multistage network systems, we hypothesized that the altered connectivity of visual networks contributes to social cognition impairment in ASD. In the present review, we focused on studies of altered connectivity of visual and attention networks in ASD using visual evoked potentials (VEPs), event-related potentials (ERPs), and diffusion tensor imaging (DTI). A series of VEP, ERP, and DTI studies conducted in our laboratory have demonstrated complex alterations (impairment and enhancement) of visual and attention networks in ASD. Recent data have suggested that the atypical visual perception observed in ASD is caused by altered connectivity within parallel visual pathways and attention networks, thereby contributing to the impaired social communication observed in ASD. Therefore, we conclude that the underlying pathophysiological mechanism of ASD constitutes a “connectopathy.” PMID:29170625

  8. Sleep abnormalities in children with Dravet syndrome.

    PubMed

    Dhamija, Radhika; Erickson, Maia K; St Louis, Erik K; Wirrell, Elaine; Kotagal, Suresh

    2014-05-01

    Mutations in the voltage-gated sodium channel SCN1A gene are responsible for the majority of Dravet syndrome cases. There is evidence that the Nav1.1 channel coded by the SCN1A gene is involved in sleep regulation. We evaluated sleep abnormalities in children with Dravet syndrome using nocturnal polysomnography. We identified six children at our institution with genetically confirmed Dravet syndrome who had also undergone formal sleep consultation with nocturnal polysomnography. Indications for polysomnography were parental concern of daytime fatigue or sleepiness, hyperactivity, inattention, disruptive behavior, nighttime awakenings, or nocturnal seizures. Sleep studies were scored according to guidelines of the American Academy of Sleep Medicine and non-rapid eye movement cyclic alternating pattern was visually identified and scored according to established methods. The mean age of the subjects at the time of polysomnography was 6 years. Standard polysomnography did not show any consistent abnormalities in the obstructive or central apnea index, arousal index, sleep efficiency, or architecture. Cyclic alternating pattern analysis on five patients showed an increased mean rate of 50.3% (vs 31% to 34% in neurological normal children) with a mild increase in A1 subtype of 89.4% (vs 84.5%). A2/A3 subtype (5.3% vs 7.3%) and B phase duration (22.4 vs 24.7 seconds) were similar to previously reported findings in neurologically normal children. Despite parental concerns for sleep disturbance in patients with Dravet syndrome, we could not identify abnormalities in sleep macroarchitecture. Non-rapid eye movement sleep microarchitecture was, however, abnormal, with increased A1 subtype, somewhat resembling a tracé alternant pattern of neonates and possibly suggestive of cortical synaptic immaturity in Dravet syndrome. Larger studies are needed to replicate these results. Copyright © 2014 Elsevier Inc. All rights reserved.

  9. Visualization in aerospace research with a large wall display system

    NASA Astrophysics Data System (ADS)

    Matsuo, Yuichi

    2002-05-01

    National Aerospace Laboratory of Japan has built a large- scale visualization system with a large wall-type display. The system has been operational since April 2001 and comprises a 4.6x1.5-meter (15x5-foot) rear projection screen with 3 BARCO 812 high-resolution CRT projectors. The reason we adopted the 3-gun CRT projectors is support for stereoscopic viewing, ease with color/luminosity matching and accuracy of edge-blending. The system is driven by a new SGI Onyx 3400 server of distributed shared-memory architecture with 32 CPUs, 64Gbytes memory, 1.5TBytes FC RAID disk and 6 IR3 graphics pipelines. Software is another important issue for us to make full use of the system. We have introduced some applications available in a multi- projector environment such as AVS/MPE, EnSight Gold and COVISE, and been developing some software tools that create volumetric images with using SGI graphics libraries. The system is mainly used for visualization fo computational fluid dynamics (CFD) simulation sin aerospace research. Visualized CFD results are of our help for designing an improved configuration of aerospace vehicles and analyzing their aerodynamic performances. These days we also use it for various collaborations among researchers.

  10. Binocular combination in abnormal binocular vision

    PubMed Central

    Ding, Jian; Klein, Stanley A.; Levi, Dennis M.

    2013-01-01

    We investigated suprathreshold binocular combination in humans with abnormal binocular visual experience early in life. In the first experiment we presented the two eyes with equal but opposite phase shifted sine waves and measured the perceived phase of the cyclopean sine wave. Normal observers have balanced vision between the two eyes when the two eyes' images have equal contrast (i.e., both eyes contribute equally to the perceived image and perceived phase = 0°). However, in observers with strabismus and/or amblyopia, balanced vision requires a higher contrast image in the nondominant eye (NDE) than the dominant eye (DE). This asymmetry between the two eyes is larger than predicted from the contrast sensitivities or monocular perceived contrast of the two eyes and is dependent on contrast and spatial frequency: more asymmetric with higher contrast and/or spatial frequency. Our results also revealed a surprising NDE-to-DE enhancement in some of our abnormal observers. This enhancement is not evident in normal vision because it is normally masked by interocular suppression. However, in these abnormal observers the NDE-to-DE suppression was weak or absent. In the second experiment, we used the identical stimuli to measure the perceived contrast of a cyclopean grating by matching the binocular combined contrast to a standard contrast presented to the DE. These measures provide strong constraints for model fitting. We found asymmetric interocular interactions in binocular contrast perception, which was dependent on both contrast and spatial frequency in the same way as in phase perception. By introducing asymmetric parameters to the modified Ding-Sperling model including interocular contrast gain enhancement, we succeeded in accounting for both binocular combined phase and contrast simultaneously. Adding binocular contrast gain control to the modified Ding-Sperling model enabled us to predict the results of dichoptic and binocular contrast discrimination experiments

  11. Binocular combination in abnormal binocular vision.

    PubMed

    Ding, Jian; Klein, Stanley A; Levi, Dennis M

    2013-02-08

    We investigated suprathreshold binocular combination in humans with abnormal binocular visual experience early in life. In the first experiment we presented the two eyes with equal but opposite phase shifted sine waves and measured the perceived phase of the cyclopean sine wave. Normal observers have balanced vision between the two eyes when the two eyes' images have equal contrast (i.e., both eyes contribute equally to the perceived image and perceived phase = 0°). However, in observers with strabismus and/or amblyopia, balanced vision requires a higher contrast image in the nondominant eye (NDE) than the dominant eye (DE). This asymmetry between the two eyes is larger than predicted from the contrast sensitivities or monocular perceived contrast of the two eyes and is dependent on contrast and spatial frequency: more asymmetric with higher contrast and/or spatial frequency. Our results also revealed a surprising NDE-to-DE enhancement in some of our abnormal observers. This enhancement is not evident in normal vision because it is normally masked by interocular suppression. However, in these abnormal observers the NDE-to-DE suppression was weak or absent. In the second experiment, we used the identical stimuli to measure the perceived contrast of a cyclopean grating by matching the binocular combined contrast to a standard contrast presented to the DE. These measures provide strong constraints for model fitting. We found asymmetric interocular interactions in binocular contrast perception, which was dependent on both contrast and spatial frequency in the same way as in phase perception. By introducing asymmetric parameters to the modified Ding-Sperling model including interocular contrast gain enhancement, we succeeded in accounting for both binocular combined phase and contrast simultaneously. Adding binocular contrast gain control to the modified Ding-Sperling model enabled us to predict the results of dichoptic and binocular contrast discrimination experiments

  12. Effectiveness of glucose monitoring systems modified for the visually impaired.

    PubMed

    Bernbaum, M; Albert, S G; Brusca, S; McGinnis, J; Miller, D; Hoffmann, J W; Mooradian, A D

    1993-10-01

    To compare three glucose meters modified for use by individuals with diabetes and visual impairment regarding accuracy, precision, and clinical reliability. Ten subjects with diabetes and visual impairment performed self-monitoring of blood glucose using each of the three commercially available blood glucose meters modified for visually impaired users (the AccuChek Freedom [Boehringer Mannheim, Indianapolis, IN], the Diascan SVM [Home Diagnostics, Eatontown, NJ], and the One Touch [Lifescan, Milpitas, CA]). The meters were independently evaluated by a laboratory technologist for precision and accuracy determinations. Only two meters were acceptable with regard to laboratory precision (coefficient of variation < 10%)--the Accuchek and the One Touch. The Accuchek and the One Touch did not differ significantly with regard to laboratory estimates of accuracy. A great discrepancy of the clinical reliability results was observed between these two meters. The Accuchek maintained a high degree of reliability (y = 0.99X + 0.44, r = 0.97, P = 0.001). The visually impaired subjects were unable to perform reliable testing using the One Touch system because of a lack of appropriate tactile landmarks and auditory signals. In addition to laboratory assessments of glucose meters, monitoring systems designed for the visually impaired must include adequate tactile and audible feedback features to allow for the acquisition and placement of appropriate blood samples.

  13. A visually guided collision warning system with a neuromorphic architecture.

    PubMed

    Okuno, Hirotsugu; Yagi, Tetsuya

    2008-12-01

    We have designed a visually guided collision warning system with a neuromorphic architecture, employing an algorithm inspired by the visual nervous system of locusts. The system was implemented with mixed analog-digital integrated circuits consisting of an analog resistive network and field-programmable gate array (FPGA) circuits. The resistive network processes the interaction between the laterally spreading excitatory and inhibitory signals instantaneously, which is essential for real-time computation of collision avoidance with a low power consumption and a compact hardware. The system responded selectively to approaching objects of simulated movie images at close range. The system was, however, confronted with serious noise problems due to the vibratory ego-motion, when it was installed in a mobile miniature car. To overcome this problem, we developed the algorithm, which is also installable in FPGA circuits, in order for the system to respond robustly during the ego-motion.

  14. Visual Complexity in Orthographic Learning: Modeling Learning across Writing System Variations

    ERIC Educational Resources Information Center

    Chang, Li-Yun; Plaut, David C.; Perfetti, Charles A.

    2016-01-01

    The visual complexity of orthographies varies across writing systems. Prior research has shown that complexity strongly influences the initial stage of reading development: the perceptual learning of grapheme forms. This study presents a computational simulation that examines the degree to which visual complexity leads to grapheme learning…

  15. Basal Ganglia Shape Abnormalities in the Unaffected Siblings of Schizophrenia Patients

    PubMed Central

    Mamah, Daniel; Harms, Michael P.; Wang, Lei; Barch, Deanna; Thompson, Paul; Kim, Jaeyun; Miller, Michael I.; Csernansky, John G.

    2008-01-01

    Objective Abnormalities of basal ganglia structure in schizophrenia have been attributed to the effects of antipsychotic drugs. Our aim was to test the hypothesis that abnormalities of basal ganglia structure are intrinsic features of schizophrenia, by assessing basal ganglia volume and shape in the unaffected siblings of schizophrenia subjects. Method The study involved 25 pairs of schizophrenia subjects and their unaffected siblings and 40 pairs of healthy controls and their siblings. Large deformation, high-dimensional brain mapping was used to obtain surface representations of the caudate, putamen, and globus pallidus. Surfaces were derived from transformations of anatomical templates and shapes were analyzed using reduced-dimensional measures of surface variability (i.e. principal components and canonical analysis). Canonical functions were derived using schizophrenia and control groups, and were then used to compare shapes in the sibling groups. To visualize shape differences, maps of the estimated surface displacement between groups were created. Results In the caudate, putamen and globus pallidus, the degree of shape abnormality observed in the siblings of the schizophrenia subjects was intermediate between the schizophrenia subjects and the controls. In the schizophrenia subjects, significant correlations were observed between measures of caudate, putamen and globus pallidus structure and the selected measures of lifetime psychopathology. Conclusions Attenuated abnormalities of basal ganglia structure are present in the unaffected siblings of schizophrenia subjects. This finding implies that basal ganglia structural abnormalities observed in subjects with schizophrenia are at least in part an intrinsic feature of the illness. PMID:18295189

  16. Objective functional visual outcomes of cataract surgery in patients with good preoperative visual acuity

    PubMed Central

    Zhu, X; Ye, H; He, W; Yang, J; Dai, J; Lu, Y

    2017-01-01

    Purpose To explore the objective functional visual outcomes of cataract surgery in patients with good preoperative visual acuity. Methods We enrolled 130 cataract patients whose best-corrected visual acuity (BCVA) was 20/40 or better preoperatively. Objective visual functions were evaluated with a KR-1W analyzer before and at 1 month after cataract surgery. Results The nuclear (N), cortical (C), and N+C groups had very high preoperative ocular and internal total high-order aberrations (HOAs), coma, and abnormal spherical aberrations. At 1 month after cataract surgery, in addition to the remarkable increase of both uncorrected visual acuity and BCVA, both ocular and internal HOAs in the three groups decreased significantly after cataract surgery (all P<0.05). Point spread function and modulation transfer functions were also improved significantly in these patients (all P<0.05). Conclusions The objective functional vision of patients with 20/40 or better preoperative BCVA improved significantly after cataract surgery. This finding shows that the arbitrary threshold of BCVA worse than 20/40 in China cannot always be used to determine who will benefit from cataract surgery. PMID:27858933

  17. NOAA's Science On a Sphere Education Program: Application of a Scientific Visualization System to Teach Earth System Science and Improve our Understanding About Creating Effective Visualizations

    NASA Astrophysics Data System (ADS)

    McDougall, C.; McLaughlin, J.

    2008-12-01

    NOAA has developed several programs aimed at facilitating the use of earth system science data and data visualizations by formal and informal educators. One of them, Science On a Sphere, a visualization display tool and system that uses networked LCD projectors to display animated global datasets onto the outside of a suspended, 1.7-meter diameter opaque sphere, enables science centers, museums, and universities to display real-time and current earth system science data. NOAA's Office of Education has provided grants to such education institutions to develop exhibits featuring Science On a Sphere (SOS) and create content for and evaluate audience impact. Currently, 20 public education institutions have permanent Science On a Sphere exhibits and 6 more will be installed soon. These institutions and others that are working to create and evaluate content for this system work collaboratively as a network to improve our collective knowledge about how to create educationally effective visualizations. Network members include other federal agencies, such as, NASA and the Dept. of Energy, and major museums such as Smithsonian and American Museum of Natural History, as well as a variety of mid-sized and small museums and universities. Although the audiences in these institutions vary widely in their scientific awareness and understanding, we find there are misconceptions and lack of familiarity with viewing visualizations that are common among the audiences. Through evaluations performed in these institutions we continue to evolve our understanding of how to create content that is understandable by those with minimal scientific literacy. The findings from our network will be presented including the importance of providing context, real-world connections and imagery to accompany the visualizations and the need for audience orientation before the visualizations are viewed. Additionally, we will review the publicly accessible virtual library housing over 200 datasets for SOS

  18. Color Processing in the Early Visual System of Drosophila.

    PubMed

    Schnaitmann, Christopher; Haikala, Väinö; Abraham, Eva; Oberhauser, Vitus; Thestrup, Thomas; Griesbeck, Oliver; Reiff, Dierk F

    2018-01-11

    Color vision extracts spectral information by comparing signals from photoreceptors with different visual pigments. Such comparisons are encoded by color-opponent neurons that are excited at one wavelength and inhibited at another. Here, we examine the circuit implementation of color-opponent processing in the Drosophila visual system by combining two-photon calcium imaging with genetic dissection of visual circuits. We report that color-opponent processing of UV short /blue and UV long /green is already implemented in R7/R8 inner photoreceptor terminals of "pale" and "yellow" ommatidia, respectively. R7 and R8 photoreceptors of the same type of ommatidia mutually inhibit each other directly via HisCl1 histamine receptors and receive additional feedback inhibition that requires the second histamine receptor Ort. Color-opponent processing at the first visual synapse represents an unexpected commonality between Drosophila and vertebrates; however, the differences in the molecular and cellular implementation suggest that the same principles evolved independently. Copyright © 2017 Elsevier Inc. All rights reserved.

  19. Gamma abnormalities during perception of illusory figures in autism.

    PubMed

    Brown, Caroline; Gruber, Thomas; Boucher, Jill; Rippon, Gina; Brock, Jon

    2005-06-01

    This experiment was designed to test the hypothesis that perceptual abnormalities in autism might be associated with alteration of induced gamma activity patterns overlying visual cortical regions. EEG was recorded from six adolescents with autism and eight controls matched on chronological age, and verbal and nonverbal mental age, whilst identifying the presence or absence of an illusory Kanizsa shape. Although there were no reaction time or accuracy differences between the groups there were significant task-related differences in cortical activity. Control participants showed typical gamma-band activity over parietal regions at around 350 msec post onset of shape trials, similar to gamma patterns found in previous studies with non-impaired adults. In contrast, autistic participants showed overall increased activity, including an early 100 msec gamma peak and a late induced peak, 50 to 70 msec earlier than that shown by the control group. We interpret the abnormal gamma activity to reflect decreased "signal to noise" due to decreased inhibitory processing. In this experiment we did not establish a link between altered perception and abnormal gamma, as the autistic participants' behaviour did not differ from the controls. Future work should be designed to replicate this phenomenon and establish the perceptual consequences of altered gamma activity.

  20. Visual Aversive Learning Compromises Sensory Discrimination.

    PubMed

    Shalev, Lee; Paz, Rony; Avidan, Galia

    2018-03-14

    Aversive learning is thought to modulate perceptual thresholds, which can lead to overgeneralization. However, it remains undetermined whether this modulation is domain specific or a general effect. Moreover, despite the unique role of the visual modality in human perception, it is unclear whether this aspect of aversive learning exists in this modality. The current study was designed to examine the effect of visual aversive outcomes on the perception of basic visual and auditory features. We tested the ability of healthy participants, both males and females, to discriminate between neutral stimuli, before and after visual learning. In each experiment, neutral stimuli were associated with aversive images in an experimental group and with neutral images in a control group. Participants demonstrated a deterioration in discrimination (higher discrimination thresholds) only after aversive learning. This deterioration was measured for both auditory (tone frequency) and visual (orientation and contrast) features. The effect was replicated in five different experiments and lasted for at least 24 h. fMRI neural responses and pupil size were also measured during learning. We showed an increase in neural activations in the anterior cingulate cortex, insula, and amygdala during aversive compared with neutral learning. Interestingly, the early visual cortex showed increased brain activity during aversive compared with neutral context trials, with identical visual information. Our findings imply the existence of a central multimodal mechanism, which modulates early perceptual properties, following exposure to negative situations. Such a mechanism could contribute to abnormal responses that underlie anxiety states, even in new and safe environments. SIGNIFICANCE STATEMENT Using a visual aversive-learning paradigm, we found deteriorated discrimination abilities for visual and auditory stimuli that were associated with visual aversive stimuli. We showed increased neural

  1. Prevalence and distribution of congenital abnormalities in Turkey: differences between the prenatal and postnatal periods.

    PubMed

    Oztarhan, Kazim; Gedikbasi, Ali; Yildirim, Dogukan; Arslan, Oguz; Adal, Erdal; Kavuncuoglu, Sultan; Ozbek, Sibel; Ceylan, Yavuz

    2010-12-01

    The aim of this study was to determine the distribution of cases associated with congenital abnormalities during the following three periods: pregnancy, birth, and the neonatal period. This was a retrospective study of cases between 2002 and 2006. All abnormal pregnancies, elective terminations of pregnancies, stillbirths, and births with congenital abnormalities managed in the Neonatology Unit were classified based on the above distribution scheme. During the 5-year study period, 1906 cases with congenital abnormalities were recruited, as follows: 640 prenatally detected and terminated cases, with most abnormalities related to the central nervous system, chromosomes, and urogenital system (56.7%, 12.7%, and 8.9%, respectively); 712 neonates with congenital abnormalities (congenital heart disease [49.2%], central nervous system abnormalities [14.7%], and urogenital system abnormalities [12.9%]); and hospital stillbirths, of which 34.2% had malformations (220 prenatal cases [34.4%] had multiple abnormalities, whereas 188 liveborn cases [26.4%] had multiple abnormalities). The congenital abnormalities rate between 2002 and 2006 was 2.07%. Systematic screening for fetal anomalies is the primary means for identification of affected pregnancies. © 2010 The Authors. Congenital Anomalies © 2010 Japanese Teratology Society.

  2. Design and implementation of visualization methods for the CHANGES Spatial Decision Support System

    NASA Astrophysics Data System (ADS)

    Cristal, Irina; van Westen, Cees; Bakker, Wim; Greiving, Stefan

    2014-05-01

    The CHANGES Spatial Decision Support System (SDSS) is a web-based system aimed for risk assessment and the evaluation of optimal risk reduction alternatives at local level as a decision support tool in long-term natural risk management. The SDSS use multidimensional information, integrating thematic, spatial, temporal and documentary data. The role of visualization in this context becomes of vital importance for efficiently representing each dimension. This multidimensional aspect of the required for the system risk information, combined with the diversity of the end-users imposes the use of sophisticated visualization methods and tools. The key goal of the present work is to exploit efficiently the large amount of data in relation to the needs of the end-user, utilizing proper visualization techniques. Three main tasks have been accomplished for this purpose: categorization of the end-users, the definition of system's modules and the data definition. The graphical representation of the data and the visualization tools were designed to be relevant to the data type and the purpose of the analysis. Depending on the end-users category, each user should have access to different modules of the system and thus, to the proper visualization environment. The technologies used for the development of the visualization component combine the latest and most innovative open source JavaScript frameworks, such as OpenLayers 2.13.1, ExtJS 4 and GeoExt 2. Moreover, the model-view-controller (MVC) pattern is used in order to ensure flexibility of the system at the implementation level. Using the above technologies, the visualization techniques implemented so far offer interactive map navigation, querying and comparison tools. The map comparison tools are of great importance within the SDSS and include the following: swiping tool for comparison of different data of the same location; raster subtraction for comparison of the same phenomena varying in time; linked views for comparison

  3. Sensitivity of visual evoked potentials and spectral domain optical coherence tomography in early relapsing remitting multiple sclerosis.

    PubMed

    Behbehani, Raed; Ahmed, Samar; Al-Hashel, Jasem; Rousseff, Rossen T; Alroughani, Raed

    2017-02-01

    Visual evoked potentials and spectral-domain optical coherence tomography are common ancillary studies that assess the visual pathways from a functional and structural aspect, respectively. To compare prevalence of abnormalities of Visual evoked potentials (VEP) and spectral-domain optical coherence tomography (SDOCT) in patients with relapsing remitting multiple sclerosis (RRMS). A cross-sectional study of 100 eyes with disease duration of less than 5 years since the diagnosis. Correlation between retinal nerve fiber layer and ganglion-cell/inner plexiform layer with pattern-reversal visual evoked potentials amplitude and latency and contrast sensitivity was performed. The prevalence of abnormalities in pattern-reversal visual VEP was 56% while that of SOCT was 48% in all eyes. There was significant negative correlations between the average RNFL (r=-0.34, p=0.001) and GCIPL (r=-0.39, p<0.001) with VEP latency. In eyes with prior optic neuritis, a significant negative correlation was seen between average RNFL (r=-0.33, p=0.037) and GCIPL (r=-0.40, p=0.010) with VEP latency. We have found higher prevalence of VEP abnormalities than SCOCT in early relapsing-remitting multiple sclerosis. This suggests that VEP has a higher sensitivity for detecting lesions of the visual pathway in patients with early RRMS. Copyright © 2016 Elsevier B.V. All rights reserved.

  4. Visual cues in low-level flight - Implications for pilotage, training, simulation, and enhanced/synthetic vision systems

    NASA Technical Reports Server (NTRS)

    Foyle, David C.; Kaiser, Mary K.; Johnson, Walter W.

    1992-01-01

    This paper reviews some of the sources of visual information that are available in the out-the-window scene and describes how these visual cues are important for routine pilotage and training, as well as the development of simulator visual systems and enhanced or synthetic vision systems for aircraft cockpits. It is shown how these visual cues may change or disappear under environmental or sensor conditions, and how the visual scene can be augmented by advanced displays to capitalize on the pilot's excellent ability to extract visual information from the visual scene.

  5. Visualization Component of Vehicle Health Decision Support System

    NASA Technical Reports Server (NTRS)

    Jacob, Joseph; Turmon, Michael; Stough, Timothy; Siegel, Herbert; Walter, patrick; Kurt, Cindy

    2008-01-01

    The visualization front-end of a Decision Support System (DSS) also includes an analysis engine linked to vehicle telemetry, and a database of learned models for known behaviors. Because the display is graphical rather than text-based, the summarization it provides has a greater information density on one screen for evaluation by a flight controller.This tool provides a system-level visualization of the state of a vehicle, and drill-down capability for more details and interfaces to separate analysis algorithms and sensor data streams. The system-level view is a 3D rendering of the vehicle, with sensors represented as icons, tied to appropriate positions within the vehicle body and colored to indicate sensor state (e.g., normal, warning, anomalous state, etc.). The sensor data is received via an Information Sharing Protocol (ISP) client that connects to an external server for real-time telemetry. Users can interactively pan, zoom, and rotate this 3D view, as well as select sensors for a detail plot of the associated time series data. Subsets of the plotted data can be selected and sent to an external analysis engine to either search for a similar time series in an historical database, or to detect anomalous events. The system overview and plotting capabilities are completely general in that they can be applied to any vehicle instrumented with a collection of sensors. This visualization component can interface with the ISP for data streams used by NASA s Mission Control Center at Johnson Space Center. In addition, it can connect to, and display results from, separate analysis engine components that identify anomalies or that search for past instances of similar behavior. This software supports NASA's Software, Intelligent Systems, and Modeling element in the Exploration Systems Research and Technology Program by augmenting the capability of human flight controllers to make correct decisions, thus increasing safety and reliability. It was designed specifically as a

  6. A novel computational model to probe visual search deficits during motor performance

    PubMed Central

    Singh, Tarkeshwar; Fridriksson, Julius; Perry, Christopher M.; Tryon, Sarah C.; Ross, Angela; Fritz, Stacy

    2016-01-01

    Successful execution of many motor skills relies on well-organized visual search (voluntary eye movements that actively scan the environment for task-relevant information). Although impairments of visual search that result from brain injuries are linked to diminished motor performance, the neural processes that guide visual search within this context remain largely unknown. The first objective of this study was to examine how visual search in healthy adults and stroke survivors is used to guide hand movements during the Trail Making Test (TMT), a neuropsychological task that is a strong predictor of visuomotor and cognitive deficits. Our second objective was to develop a novel computational model to investigate combinatorial interactions between three underlying processes of visual search (spatial planning, working memory, and peripheral visual processing). We predicted that stroke survivors would exhibit deficits in integrating the three underlying processes, resulting in deteriorated overall task performance. We found that normal TMT performance is associated with patterns of visual search that primarily rely on spatial planning and/or working memory (but not peripheral visual processing). Our computational model suggested that abnormal TMT performance following stroke is associated with impairments of visual search that are characterized by deficits integrating spatial planning and working memory. This innovative methodology provides a novel framework for studying how the neural processes underlying visual search interact combinatorially to guide motor performance. NEW & NOTEWORTHY Visual search has traditionally been studied in cognitive and perceptual paradigms, but little is known about how it contributes to visuomotor performance. We have developed a novel computational model to examine how three underlying processes of visual search (spatial planning, working memory, and peripheral visual processing) contribute to visual search during a visuomotor task. We

  7. Prevalence of human papilloma virus infections and cervical cytological abnormalities among Korean women with systemic lupus erythematosus.

    PubMed

    Lee, You-Hyun; Choe, Jung-Yoon; Park, Sung-Hoon; Park, Yong-Wook; Lee, Shin-Seok; Kang, Young-Mo; Nam, Eon-Jeong; Park, Won; Kwon, Seong-Ryul; Bae, Sang-Cheol; Kim, Yun-Jung; Suh, Chang-Hee; Kim, Hyoun-Ah; Hur, Nam Wook; Lee, Jisoo

    2010-10-01

    We performed a multicenter cross-sectional study of 134 sexually active systemic lupus erythematosus (SLE) patients to investigate the prevalence of and risk factors for high risk human papilloma virus (HPV) infection and cervical cytological abnormalities among Korean women with SLE. In this multicenter cross-sectional study, HPV testing and routine cervical cytologic examination was performed. HPV was typed using a hybrid method or the polymerase chain reaction. Data on 4,595 healthy women were used for comparison. SLE patients had greater prevalence of high-risk HPV infection (24.6% vs. 7.9%, P<0.001, odds ratio 3.8, 95% confidence interval 2.5-5.7) and of abnormal cervical cytology (16.4 vs. 2.8%, P<0.001, OR 4.4, 95% CI 2.5-7.8) compared with controls. SLE itself was identified as independent risk factors for high risk HPV infection among Korean women (OR 3.8, 95% CI 2.5-5.7) along with ≥2 sexual partners (OR 8.5, 95% CI 1.2-61.6), and Pap smear abnormalities (OR 97.3, 95% CI 6.5-1,456.7). High-risk HPV infection and cervical cytological abnormalities were more common among Korean women with SLE than controls. SLE itself may be a risk factor for HPV infection among Korean women, suggesting the importance of close monitoring of HPV infections and abnormal Pap smears in SLE patients.

  8. User-assisted video segmentation system for visual communication

    NASA Astrophysics Data System (ADS)

    Wu, Zhengping; Chen, Chun

    2002-01-01

    Video segmentation plays an important role for efficient storage and transmission in visual communication. In this paper, we introduce a novel video segmentation system using point tracking and contour formation techniques. Inspired by the results from the study of the human visual system, we intend to solve the video segmentation problem into three separate phases: user-assisted feature points selection, feature points' automatic tracking, and contour formation. This splitting relieves the computer of ill-posed automatic segmentation problems, and allows a higher level of flexibility of the method. First, the precise feature points can be found using a combination of user assistance and an eigenvalue-based adjustment. Second, the feature points in the remaining frames are obtained using motion estimation and point refinement. At last, contour formation is used to extract the object, and plus a point insertion process to provide the feature points for next frame's tracking.

  9. Neonatal brain abnormalities and memory and learning outcomes at 7 years in children born very preterm.

    PubMed

    Omizzolo, Cristina; Scratch, Shannon E; Stargatt, Robyn; Kidokoro, Hiroyuki; Thompson, Deanne K; Lee, Katherine J; Cheong, Jeanie; Neil, Jeffrey; Inder, Terrie E; Doyle, Lex W; Anderson, Peter J

    2014-01-01

    Using prospective longitudinal data from 198 very preterm and 70 full term children, this study characterised the memory and learning abilities of very preterm children at 7 years of age in both verbal and visual domains. The relationship between the extent of brain abnormalities on neonatal magnetic resonance imaging (MRI) and memory and learning outcomes at 7 years of age in very preterm children was also investigated. Neonatal MRI scans were qualitatively assessed for global, white-matter, cortical grey-matter, deep grey-matter, and cerebellar abnormalities. Very preterm children performed less well on measures of immediate memory, working memory, long-term memory, and learning compared with term-born controls. Neonatal brain abnormalities, and in particular deep grey-matter abnormality, were associated with poorer memory and learning performance at 7 years in very preterm children. Findings support the importance of cerebral neonatal pathology for predicting later memory and learning function.

  10. Chromosome and molecular abnormalities in myelodysplastic syndromes.

    PubMed

    Fenaux, Pierre

    2001-06-01

    Cytogenetic abnormalities are seen in approximately 50% of cases of myelodysplastic syndrome (MDS) and 80% of cases of secondary MDS (following chemotherapy or radiotherapy). These abnormalities generally consist of partial or complete chromosome deletion or addition (del5q, -7, +8, -Y, del20q), whereas balanced or unbalanced translocations are rarely found in MDS. Fluorescence hybridization techniques (fluorescence in situ hybridization [FISH], multiplex FISH, and spectral karyotyping) are useful in detecting chromosomal anomalies in cases in which few mitoses are obtained or rearrangements are complex. Ras mutations are the molecular abnormalities most frequently found in MDS, followed by p15 gene hypermethylation, FLT3 duplications, and p53 mutations, but none of these abnormalities are specific for MDS. The rare cases of balanced translocations in MDS have allowed the identification of genes whose rearrangements appear to play a role in the pathogenesis of some cases of MDS. These genes include MDS1-EVI1 in t(3;3) or t(3;21) translocations, TEL in t(5;12), HIP1 in t(5;7), MLF1 in t(3;5), and MEL1 in t(1;3). Genes more frequently implicated in the pathogenesis of MDS cases, such as those involving del5q, remain unknown, although some candidate genes are currently being studied. Cytogenetic and known molecular abnormalities generally carry a poor prognosis in MDS and can be incorporated into prognostic scoring systems such as the International Prognostic Scoring System.

  11. Retinotopic maps and foveal suppression in the visual cortex of amblyopic adults

    PubMed Central

    Conner, Ian P; Odom, J Vernon; Schwartz, Terry L; Mendola, Janine D

    2007-01-01

    Amblyopia is a developmental visual disorder associated with loss of monocular acuity and sensitivity as well as profound alterations in binocular integration. Abnormal connections in visual cortex are known to underlie this loss, but the extent to which these abnormalities are regionally or retinotopically specific has not been fully determined. This functional magnetic resonance imaging (fMRI) study compared the retinotopic maps in visual cortex produced by each individual eye in 19 adults (7 esotropic strabismics, 6 anisometropes and 6 controls). In our standard viewing condition, the non-tested eye viewed a dichoptic homogeneous mid-level grey stimulus, thereby permitting some degree of binocular interaction. Regions-of-interest analysis was performed for extrafoveal V1, extrafoveal V2 and the foveal representation at the occipital pole. In general, the blood oxygenation level-dependent (BOLD) signal was reduced for the amblyopic eye. At the occipital pole, population receptive fields were shifted to represent more parafoveal locations for the amblyopic eye, compared with the fellow eye, in some subjects. Interestingly, occluding the fellow eye caused an expanded foveal representation for the amblyopic eye in one early–onset strabismic subject with binocular suppression, indicating real-time cortical remapping. In addition, a few subjects actually showed increased activity in parietal and temporal cortex when viewing with the amblyopic eye. We conclude that, even in a heterogeneous population, abnormal early visual experience commonly leads to regionally specific cortical adaptations. PMID:17627994

  12. Retinotopic maps and foveal suppression in the visual cortex of amblyopic adults.

    PubMed

    Conner, Ian P; Odom, J Vernon; Schwartz, Terry L; Mendola, Janine D

    2007-08-15

    Amblyopia is a developmental visual disorder associated with loss of monocular acuity and sensitivity as well as profound alterations in binocular integration. Abnormal connections in visual cortex are known to underlie this loss, but the extent to which these abnormalities are regionally or retinotopically specific has not been fully determined. This functional magnetic resonance imaging (fMRI) study compared the retinotopic maps in visual cortex produced by each individual eye in 19 adults (7 esotropic strabismics, 6 anisometropes and 6 controls). In our standard viewing condition, the non-tested eye viewed a dichoptic homogeneous mid-level grey stimulus, thereby permitting some degree of binocular interaction. Regions-of-interest analysis was performed for extrafoveal V1, extrafoveal V2 and the foveal representation at the occipital pole. In general, the blood oxygenation level-dependent (BOLD) signal was reduced for the amblyopic eye. At the occipital pole, population receptive fields were shifted to represent more parafoveal locations for the amblyopic eye, compared with the fellow eye, in some subjects. Interestingly, occluding the fellow eye caused an expanded foveal representation for the amblyopic eye in one early-onset strabismic subject with binocular suppression, indicating real-time cortical remapping. In addition, a few subjects actually showed increased activity in parietal and temporal cortex when viewing with the amblyopic eye. We conclude that, even in a heterogeneous population, abnormal early visual experience commonly leads to regionally specific cortical adaptations.

  13. Abnormal ventricular development in preterm neonates with visually normal MRIs

    NASA Astrophysics Data System (ADS)

    Shi, Jie; Wang, Yalin; Lao, Yi; Ceschin, Rafael; Mi, Liang; Nelson, Marvin D.; Panigrahy, Ashok; Leporé, Natasha

    2015-12-01

    Children born preterm are at risk for a wide range of neurocognitive and neurobehavioral disorders. Some of these may stem from early brain abnormalities at the neonatal age. Hence, a precise characterization of neonatal neuroanatomy may help inform treatment strategies. In particular, the ventricles are often enlarged in neurocognitive disorders, due to atrophy of surrounding tissues. Here we present a new pipeline for the detection of morphological and relative pose differences in the ventricles of premature neonates compared to controls. To this end, we use a new hyperbolic Ricci flow based mapping of the ventricular surfaces of each subjects to the Poincaré disk. Resulting surfaces are then registered to a template, and a between group comparison is performed using multivariate tensor-based morphometry. We also statistically compare the relative pose of the ventricles within the brain between the two groups, by performing a Procrustes alignment between each subject's ventricles and an average shape. For both types of analyses, differences were found in the left ventricles between the two groups.

  14. A highly sensitive and temporal visualization system for gaseous ethanol with chemiluminescence enhancer.

    PubMed

    Arakawa, Takahiro; Ando, Eri; Wang, Xin; Kumiko, Miyajima; Kudo, Hiroyuki; Saito, Hirokazu; Mitani, Tomoyo; Takahashi, Mitsuo; Mitsubayashi, Kohji

    2012-01-01

    A two-dimensional gaseous ethanol visualization system has been developed and demonstrated using a horseradish peroxidase-luminol-hydrogen peroxide system with high-purity luminol solution and a chemiluminescence (CL) enhancer. This system measures ethanol concentrations as intensities of CL via the luminol reaction. CL was emitted when the gaseous ethanol was injected onto an enzyme-immobilized membrane, which was employed as a screen for two-dimensional gas visualization. The average intensity of CL on the substrate was linearly related to the concentration of standard ethanol gas. These results were compared with the CL intensity of the CCD camera recording image in the visualization system. This system is available for gas components not only for spatial but also for temporal analysis in real time. A high-purity sodium salt HG solution (L-HG) instead of standard luminol solution and an enhancer, eosin Y (EY) solution, were adapted for improvement of CL intensity of the system. The visualization of gaseous ethanol was achieved at a detection limit of 3 ppm at optimized concentrations of L-HG solution and EY. Copyright © 2011 John Wiley & Sons, Ltd.

  15. Reader error, object recognition, and visual search

    NASA Astrophysics Data System (ADS)

    Kundel, Harold L.

    2004-05-01

    Small abnormalities such as hairline fractures, lung nodules and breast tumors are missed by competent radiologists with sufficient frequency to make them a matter of concern to the medical community; not only because they lead to litigation but also because they delay patient care. It is very easy to attribute misses to incompetence or inattention. To do so may be placing an unjustified stigma on the radiologists involved and may allow other radiologists to continue a false optimism that it can never happen to them. This review presents some of the fundamentals of visual system function that are relevant to understanding the search for and the recognition of small targets embedded in complicated but meaningful backgrounds like chests and mammograms. It presents a model for visual search that postulates a pre-attentive global analysis of the retinal image followed by foveal checking fixations and eventually discovery scanning. The model will be used to differentiate errors of search, recognition and decision making. The implications for computer aided diagnosis and for functional workstation design are discussed.

  16. Moderate perinatal thyroid hormone insufficiency alters visual system function in adult rats.

    PubMed

    Boyes, William K; Degn, Laura; George, Barbara Jane; Gilbert, Mary E

    2018-04-21

    Thyroid hormone (TH) is critical for many aspects of neurodevelopment and can be disrupted by a variety of environmental contaminants. Sensory systems, including audition and vision are vulnerable to TH insufficiencies, but little data are available on visual system development at less than severe levels of TH deprivation. The goal of the current experiments was to explore dose-response relations between graded levels of TH insufficiency during development and the visual function of adult offspring. Pregnant Long Evans rats received 0 or 3 ppm (Experiment 1), or 0, 1, 2, or 3 ppm (Experiment 2) of propylthiouracil (PTU), an inhibitor of thyroid hormone synthesis, in drinking water from gestation day (GD) 6 to postnatal day (PN) 21. Treatment with PTU caused dose-related reductions of serum T4, with recovery on termination of exposure, and euthyroidism by the time of visual function testing. Tests of retinal (electroretinograms; ERGs) and visual cortex (visual evoked potentials; VEPs) function were assessed in adult offspring. Dark-adapted ERG a-waves, reflecting rod photoreceptors, were increased in amplitude by PTU. Light-adapted green flicker ERGs, reflecting M-cone photoreceptors, were reduced by PTU exposure. UV-flicker ERGs, reflecting S-cones, were not altered. Pattern-elicited VEPs were significantly reduced by 2 and 3 ppm PTU across a range of stimulus contrast values. The slope of VEP amplitude-log contrast functions was reduced by PTU, suggesting impaired visual contrast gain. Visual contrast gain primarily reflects function of visual cortex, and is responsible for adjusting sensitivity of perceptual mechanisms in response to changing visual scenes. The results indicate that moderate levels of pre-and post-natal TH insufficiency led to alterations in visual function of adult rats, including both retinal and visual cortex sites of dysfunction. Copyright © 2018. Published by Elsevier B.V.

  17. The visual system in migraine: from the bench side to the office.

    PubMed

    Kowacs, Pedro A; Utiumi, Marco A; Piovesan, Elcio J

    2015-02-01

    Throughout history, migraine-associated visual symptoms have puzzled patients, doctors, and neuroscientists. The visual aspects of migraine extend far beyond the aura phenomena, and have several clinical implications. A narrative review was conducted, beginning with migraine mechanisms, then followed by pertinent aspects of the anatomy of visual pathways, clinical features, implications of the visual system on therapy, migraine on visually impaired populations, treatment of visual auras and ocular (retinal) migraine, effect of prophylactic migraine treatments on visual aura, visual symptoms induced by anti-migraine or anti-headache drugs, and differential diagnosis. A comprehensive narrative review from both basic and clinical standpoints on the visual aspects of migraine was attained; however, the results were biased to provide any useful information for the clinician. This paper achieved its goals of addressing and condensing information on the pathophysiology of the visual aspects of migraine and its clinical aspects, especially with regards to therapy, making it useful not only for those unfamiliar to the theme but to experienced physicians as well. © 2015 American Headache Society.

  18. Visual System Involvement in Patients with Newly Diagnosed Parkinson Disease.

    PubMed

    Arrigo, Alessandro; Calamuneri, Alessandro; Milardi, Demetrio; Mormina, Enricomaria; Rania, Laura; Postorino, Elisa; Marino, Silvia; Di Lorenzo, Giuseppe; Anastasi, Giuseppe Pio; Ghilardi, Maria Felice; Aragona, Pasquale; Quartarone, Angelo; Gaeta, Michele

    2017-12-01

    Purpose To assess intracranial visual system changes of newly diagnosed Parkinson disease in drug-naïve patients. Materials and Methods Twenty patients with newly diagnosed Parkinson disease and 20 age-matched control subjects were recruited. Magnetic resonance (MR) imaging (T1-weighted and diffusion-weighted imaging) was performed with a 3-T MR imager. White matter changes were assessed by exploring a white matter diffusion profile by means of diffusion-tensor imaging-based parameters and constrained spherical deconvolution-based connectivity analysis and by means of white matter voxel-based morphometry (VBM). Alterations in occipital gray matter were investigated by means of gray matter VBM. Morphologic analysis of the optic chiasm was based on manual measurement of regions of interest. Statistical testing included analysis of variance, t tests, and permutation tests. Results In the patients with Parkinson disease, significant alterations were found in optic radiation connectivity distribution, with decreased lateral geniculate nucleus V2 density (F, -8.28; P < .05), a significant increase in optic radiation mean diffusivity (F, 7.5; P = .014), and a significant reduction in white matter concentration. VBM analysis also showed a significant reduction in visual cortical volumes (P < .05). Moreover, the chiasmatic area and volume were significantly reduced (P < .05). Conclusion The findings show that visual system alterations can be detected in early stages of Parkinson disease and that the entire intracranial visual system can be involved. © RSNA, 2017 Online supplemental material is available for this article.

  19. Desktop chaotic systems: Intuition and visualization

    NASA Technical Reports Server (NTRS)

    Bright, Michelle M.; Melcher, Kevin J.; Qammar, Helen K.; Hartley, Tom T.

    1993-01-01

    This paper presents a dynamic study of the Wildwood Pendulum, a commercially available desktop system which exhibits a strange attractor. The purpose of studying this chaotic pendulum is twofold: to gain insight in the paradigmatic approach of modeling, simulating, and determining chaos in nonlinear systems; and to provide a desktop model of chaos as a visual tool. For this study, the nonlinear behavior of this chaotic pendulum is modeled, a computer simulation is performed, and an experimental performance is measured. An assessment of the pendulum in the phase plane shows the strange attractor. Through the use of a box-assisted correlation dimension methodology, the attractor dimension is determined for both the model and the experimental pendulum systems. Correlation dimension results indicate that the pendulum and the model are chaotic and their fractal dimensions are similar.

  20. Low-cost digital dynamic visualization system

    NASA Astrophysics Data System (ADS)

    Asundi, Anand K.; Sajan, M. R.

    1995-05-01

    High speed photographic systems like the image rotation camera, the Cranz Schardin camera and the drum camera are typically used for recording and visualization of dynamic events in stress analysis, fluid mechanics, etc. All these systems are fairly expensive and generally not simple to use. Furthermore they are all based on photographic film recording systems requiring time consuming and tedious wet processing of the films. Currently digital cameras are replacing to certain extent the conventional cameras for static experiments. Recently, there is lot of interest in developing and modifying CCD architectures and recording arrangements for dynamic scene analysis. Herein we report the use of a CCD camera operating in the Time Delay and Integration (TDI) mode for digitally recording dynamic scenes. Applications in solid as well as fluid impact problems are presented.

  1. The Visual System of Zebrafish and its Use to Model Human Ocular Diseases

    PubMed Central

    Gestri, Gaia; Link, Brian A; Neuhauss, Stephan CF

    2011-01-01

    Free swimming zebrafish larvae depend mainly on their sense of vision to evade predation and to catch prey. Hence there is strong selective pressure on the fast maturation of visual function and indeed the visual system already supports a number of visually-driven behaviors in the newly hatched larvae. The ability to exploit the genetic and embryonic accessibility of the zebrafish in combination with a behavioral assessment of visual system function has made the zebrafish a popular model to study vision and its diseases. Here, we review the anatomy, physiology and development of the zebrafish eye as the basis to relate the contributions of the zebrafish to our understanding of human ocular diseases. PMID:21595048

  2. Intelligent Data Visualization for Cross-Checking Spacecraft System Diagnosis

    NASA Technical Reports Server (NTRS)

    Ong, James C.; Remolina, Emilio; Breeden, David; Stroozas, Brett A.; Mohammed, John L.

    2012-01-01

    Any reasoning system is fallible, so crew members and flight controllers must be able to cross-check automated diagnoses of spacecraft or habitat problems by considering alternate diagnoses and analyzing related evidence. Cross-checking improves diagnostic accuracy because people can apply information processing heuristics, pattern recognition techniques, and reasoning methods that the automated diagnostic system may not possess. Over time, cross-checking also enables crew members to become comfortable with how the diagnostic reasoning system performs, so the system can earn the crew s trust. We developed intelligent data visualization software that helps users cross-check automated diagnoses of system faults more effectively. The user interface displays scrollable arrays of timelines and time-series graphs, which are tightly integrated with an interactive, color-coded system schematic to show important spatial-temporal data patterns. Signal processing and rule-based diagnostic reasoning automatically identify alternate hypotheses and data patterns that support or rebut the original and alternate diagnoses. A color-coded matrix display summarizes the supporting or rebutting evidence for each diagnosis, and a drill-down capability enables crew members to quickly view graphs and timelines of the underlying data. This system demonstrates that modest amounts of diagnostic reasoning, combined with interactive, information-dense data visualizations, can accelerate system diagnosis and cross-checking.

  3. Allocentric but not egocentric visual memory difficulties in adults with ADHD may represent cognitive inefficiency.

    PubMed

    Brown, Franklin C; Roth, Robert M; Katz, Lynda J

    2015-08-30

    Attention Deficit Hyperactivity Disorder (ADHD) has often been conceptualized as arising executive dysfunctions (e.g., inattention, defective inhibition). However, recent studies suggested that cognitive inefficiency may underlie many ADHD symptoms, according to reaction time and processing speed abnormalities. This study explored whether a non-timed measure of cognitive inefficiency would also be abnormal. A sample of 23 ADHD subjects was compared to 23 controls on a test that included both egocentric and allocentric visual memory subtests. A factor analysis was used to determine which cognitive variables contributed to allocentric visual memory. The ADHD sample performed significantly lower on the allocentric but not egocentric conditions. Allocentric visual memory was not associated with timed, working memory, visual perception, or mental rotation variables. This paper concluded by discussing how these results supported a cognitive inefficiency explanation for some ADHD symptoms, and discussed future research directions. Copyright © 2015 Elsevier Ireland Ltd. All rights reserved.

  4. How Information Visualization Systems Change Users' Understandings of Complex Data

    ERIC Educational Resources Information Center

    Allendoerfer, Kenneth Robert

    2009-01-01

    User-centered evaluations of information systems often focus on the usability of the system rather its usefulness. This study examined how a using an interactive knowledge-domain visualization (KDV) system affected users' understanding of a domain. Interactive KDVs allow users to create graphical representations of domains that depict important…

  5. A prototype system based on visual interactive SDM called VGC

    NASA Astrophysics Data System (ADS)

    Jia, Zelu; Liu, Yaolin; Liu, Yanfang

    2009-10-01

    In many application domains, data is collected and referenced by its geo-spatial location. Spatial data mining, or the discovery of interesting patterns in such databases, is an important capability in the development of database systems. Spatial data mining recently emerges from a number of real applications, such as real-estate marketing, urban planning, weather forecasting, medical image analysis, road traffic accident analysis, etc. It demands for efficient solutions for many new, expensive, and complicated problems. For spatial data mining of large data sets to be effective, it is also important to include humans in the data exploration process and combine their flexibility, creativity, and general knowledge with the enormous storage capacity and computational power of today's computers. Visual spatial data mining applies human visual perception to the exploration of large data sets. Presenting data in an interactive, graphical form often fosters new insights, encouraging the information and validation of new hypotheses to the end of better problem-solving and gaining deeper domain knowledge. In this paper a visual interactive spatial data mining prototype system (visual geo-classify) based on VC++6.0 and MapObject2.0 are designed and developed, the basic algorithms of the spatial data mining is used decision tree and Bayesian networks, and data classify are used training and learning and the integration of the two to realize. The result indicates it's a practical and extensible visual interactive spatial data mining tool.

  6. METHODS FOR MONITORING THE EFFECTS OF ENVIRONMENTAL TOXINS ON THE VISUAL SYSTEM.

    EPA Science Inventory

    A high percentage of neurotoxic compounds adversely effect the visual system. Our goal is to apply the tools of vision science to problems of toxicological import, exposure-related alterations in visual physiology, psychophysical function, and ocular development. Methods can ...

  7. Serial and semantic encoding of lists of words in schizophrenia patients with visual hallucinations.

    PubMed

    Brébion, Gildas; Ohlsen, Ruth I; Pilowsky, Lyn S; David, Anthony S

    2011-03-30

    Previous research has suggested that visual hallucinations in schizophrenia are associated with abnormal salience of visual mental images. Since visual imagery is used as a mnemonic strategy to learn lists of words, increased visual imagery might impede the other commonly used strategies of serial and semantic encoding. We had previously published data on the serial and semantic strategies implemented by patients when learning lists of concrete words with different levels of semantic organisation (Brébion et al., 2004). In this paper we present a re-analysis of these data, aiming at investigating the associations between learning strategies and visual hallucinations. Results show that the patients with visual hallucinations presented less serial clustering in the non-organisable list than the other patients. In the semantically organisable list with typical instances, they presented both less serial and less semantic clustering than the other patients. Thus, patients with visual hallucinations demonstrate reduced use of serial and semantic encoding in the lists made up of fairly familiar concrete words, which enable the formation of mental images. Although these results are preliminary, we propose that this different processing of the lists stems from the abnormal salience of the mental images such patients experience from the word stimuli. Copyright © 2010 Elsevier Ireland Ltd. All rights reserved.

  8. Development of the updated system of city underground pipelines based on Visual Studio

    NASA Astrophysics Data System (ADS)

    Zhang, Jianxiong; Zhu, Yun; Li, Xiangdong

    2009-10-01

    Our city has owned the integrated pipeline network management system with ArcGIS Engine 9.1 as the bottom development platform and with Oracle9i as basic database for storaging data. In this system, ArcGIS SDE9.1 is applied as the spatial data engine, and the system was a synthetic management software developed with Visual Studio visualization procedures development tools. As the pipeline update function of the system has the phenomenon of slower update and even sometimes the data lost, to ensure the underground pipeline data can real-time be updated conveniently and frequently, and the actuality and integrity of the underground pipeline data, we have increased a new update module in the system developed and researched by ourselves. The module has the powerful data update function, and can realize the function of inputting and outputting and rapid update volume of data. The new developed module adopts Visual Studio visualization procedures development tools, and uses access as the basic database to storage data. We can edit the graphics in AutoCAD software, and realize the database update using link between the graphics and the system. Practice shows that the update module has good compatibility with the original system, reliable and high update efficient of the database.

  9. Helicopter Visual Aid System

    NASA Technical Reports Server (NTRS)

    Baisley, R. L.

    1973-01-01

    The results of an evaluation of police helicopter effectiveness revealed a need for improved visual capability. A JPL program developed a method that would enhance visual observation capability for both day and night usage and demonstrated the feasibility of the adopted approach. This approach made use of remote pointable optics, a display screen, a slaved covert searchlight, and a coupled camera. The approach was proved feasible through field testing and by judgement against evaluation criteria.

  10. A 3D particle visualization system for temperature management

    NASA Astrophysics Data System (ADS)

    Lange, B.; Rodriguez, N.; Puech, W.; Rey, H.; Vasques, X.

    2011-01-01

    This paper deals with a 3D visualization technique proposed to analyze and manage energy efficiency from a data center. Data are extracted from sensors located in the IBM Green Data Center in Montpellier France. These sensors measure different information such as hygrometry, pressure and temperature. We want to visualize in real-time the large among of data produced by these sensors. A visualization engine has been designed, based on particles system and a client server paradigm. In order to solve performance problems, a Level Of Detail solution has been developed. These methods are based on the earlier work introduced by J. Clark in 1976. In this paper we introduce a particle method used for this work and subsequently we explain different simplification methods applied to improve our solution.

  11. Meiotic abnormalities

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    NONE

    1993-12-31

    Chapter 19, describes meiotic abnormalities. These include nondisjunction of autosomes and sex chromosomes, genetic and environmental causes of nondisjunction, misdivision of the centromere, chromosomally abnormal human sperm, male infertility, parental age, and origin of diploid gametes. 57 refs., 2 figs., 1 tab.

  12. History of visual systems in the Systems Engineering Simulator

    NASA Technical Reports Server (NTRS)

    Christianson, David C.

    1989-01-01

    The Systems Engineering Simulator (SES) houses a variety of real-time computer generated visual systems. The earliest machine dates from the mid-1960's and is one of the first real-time graphics systems in the world. The latest acquisition is the state-of-the-art Evans and Sutherland CT6. Between the span of time from the mid-1960's to the late 1980's, tremendous strides have been made in the real-time graphics world. These strides include advances in both software and hardware engineering. The purpose is to explore the history of the development of these real-time computer generated image systems from the first machine to the present. Hardware advances as well as software algorithm changes are presented. This history is not only quite interesting but also provides us with a perspective with which we can look backward and forward.

  13. Computed aided system for separation and classification of the abnormal erythrocytes in human blood

    NASA Astrophysics Data System (ADS)

    Wąsowicz, Michał; Grochowski, Michał; Kulka, Marek; Mikołajczyk, Agnieszka; Ficek, Mateusz; Karpieńko, Katarzyna; Cićkiewicz, Maciej

    2017-12-01

    The human peripheral blood consists of cells (red cells, white cells, and platelets) suspended in plasma. In the following research the team assessed an influence of nanodiamond particles on blood elements over various periods of time. The material used in the study consisted of samples taken from ten healthy humans of various age, different blood types and both sexes. The markings were leaded by adding to the blood unmodified diamonds and oxidation modified. The blood was put under an impact of two diamond concentrations: 20μl and 100μl. The amount of abnormal cells increased with time. The percentage of echinocytes as a result of interaction with nanodiamonds in various time intervals for individual specimens was scarce. The impact of the two diamond types had no clinical importance on red blood cells. It is supposed that as a result of longlasting exposure a dehydratation of red cells takes place, because of the function of the cells. The analysis of an influence of nanodiamond particles on blood elements was supported by computer system designed for automatic counting and classification of the Red Blood Cells (RBC). The system utilizes advanced image processing methods for RBCs separation and counting and Eigenfaces method coupled with the neural networks for RBCs classification into normal and abnormal cells purposes.

  14. Intelligent Process Abnormal Patterns Recognition and Diagnosis Based on Fuzzy Logic.

    PubMed

    Hou, Shi-Wang; Feng, Shunxiao; Wang, Hui

    2016-01-01

    Locating the assignable causes by use of the abnormal patterns of control chart is a widely used technology for manufacturing quality control. If there are uncertainties about the occurrence degree of abnormal patterns, the diagnosis process is impossible to be carried out. Considering four common abnormal control chart patterns, this paper proposed a characteristic numbers based recognition method point by point to quantify the occurrence degree of abnormal patterns under uncertain conditions and a fuzzy inference system based on fuzzy logic to calculate the contribution degree of assignable causes with fuzzy abnormal patterns. Application case results show that the proposed approach can give a ranked causes list under fuzzy control chart abnormal patterns and support the abnormity eliminating.

  15. A navigation system for the visually impaired an intelligent white cane.

    PubMed

    Fukasawa, A Jin; Magatani, Kazusihge

    2012-01-01

    In this paper, we describe about a developed navigation system that supports the independent walking of the visually impaired in the indoor space. Our developed instrument consists of a navigation system and a map information system. These systems are installed on a white cane. Our navigation system can follow a colored navigation line that is set on the floor. In this system, a color sensor installed on the tip of a white cane, this sensor senses a color of navigation line and the system informs the visually impaired that he/she is walking along the navigation line by vibration. This color recognition system is controlled by a one-chip microprocessor. RFID tags and a receiver for these tags are used in the map information system. RFID tags are set on the colored navigation line. An antenna for RFID tags and a tag receiver are also installed on a white cane. The receiver receives the area information as a tag-number and notifies map information to the user by mp3 formatted pre-recorded voice. And now, we developed the direction identification technique. Using this technique, we can detect a user's walking direction. A triaxiality acceleration sensor is used in this system. Three normal subjects who were blindfolded with an eye mask were tested with our developed navigation system. All of them were able to walk along the navigation line perfectly. We think that the performance of the system is good. Therefore, our system will be extremely valuable in supporting the activities of the visually impaired.

  16. Characteristics of Flight Simulator Visual Systems

    DTIC Science & Technology

    1981-05-01

    0 . C,...)l .l.Li J ; I a= c I 0 a= c ~ LEVEL1r AGARD ADVISORY REPORT No.164 Characteristics of Flight Simulator Visual Systems...OT\\g . E L E C l ·: .. ;. . . . . , .. , • I ,t l• • ’f) . JIJL 1 6 \\98\\ .. ~ DISTRIBUTION AND AVAILABILITY ON BACK COVER 1 NORTH ATLANTIC...Printed by Technical Editing and Reproduchton Ltd Harford House, 7-9 Charlotte St. London, WIP )HD I PREFACE The Flight Mechanics Panel (FMP) of the

  17. PERCEPT Indoor Navigation System for the Blind and Visually Impaired: Architecture and Experimentation

    PubMed Central

    Ganz, Aura; Schafer, James; Gandhi, Siddhesh; Puleo, Elaine; Wilson, Carole; Robertson, Meg

    2012-01-01

    We introduce PERCEPT system, an indoor navigation system for the blind and visually impaired. PERCEPT will improve the quality of life and health of the visually impaired community by enabling independent living. Using PERCEPT, blind users will have independent access to public health facilities such as clinics, hospitals, and wellness centers. Access to healthcare facilities is crucial for this population due to the multiple health conditions that they face such as diabetes and its complications. PERCEPT system trials with 24 blind and visually impaired users in a multistory building show PERCEPT system effectiveness in providing appropriate navigation instructions to these users. The uniqueness of our system is that it is affordable and that its design follows orientation and mobility principles. We hope that PERCEPT will become a standard deployed in all indoor public spaces, especially in healthcare and wellness facilities. PMID:23316225

  18. A Spot Reminder System for the Visually Impaired Based on a Smartphone Camera.

    PubMed

    Takizawa, Hotaka; Orita, Kazunori; Aoyagi, Mayumi; Ezaki, Nobuo; Mizuno, Shinji

    2017-02-04

    The present paper proposes a smartphone-camera-based system to assist visually impaired users in recalling their memories related to important locations, called spots, that they visited. The memories are recorded as voice memos, which can be played back when the users return to the spots. Spot-to-spot correspondence is determined by image matching based on the scale invariant feature transform. The main contribution of the proposed system is to allow visually impaired users to associate arbitrary voice memos with arbitrary spots. The users do not need any special devices or systems except smartphones and do not need to remember the spots where the voice memos were recorded. In addition, the proposed system can identify spots in environments that are inaccessible to the global positioning system. The proposed system has been evaluated by two experiments: image matching tests and a user study. The experimental results suggested the effectiveness of the system to help visually impaired individuals, including blind individuals, recall information about regularly-visited spots.

  19. Examining the Use of a Visual Analytics System for Sensemaking Tasks: Case Studies with Domain Experts.

    PubMed

    Kang, Youn-Ah; Stasko, J

    2012-12-01

    While the formal evaluation of systems in visual analytics is still relatively uncommon, particularly rare are case studies of prolonged system use by domain analysts working with their own data. Conducting case studies can be challenging, but it can be a particularly effective way to examine whether visual analytics systems are truly helping expert users to accomplish their goals. We studied the use of a visual analytics system for sensemaking tasks on documents by six analysts from a variety of domains. We describe their application of the system along with the benefits, issues, and problems that we uncovered. Findings from the studies identify features that visual analytics systems should emphasize as well as missing capabilities that should be addressed. These findings inform design implications for future systems.

  20. Abnormal Medial Prefrontal Cortex Activity in Heavy Cannabis Users During Conscious Emotional Evaluation

    PubMed Central

    Lile, Joshua A.; Hanlon, Colleen A.; Porrino, Linda J.

    2015-01-01

    Rationale Long-term heavy cannabis users (cannabis users) who are not acutely intoxicated have diminished subconscious neural responsiveness to affective stimuli. Objective This study sought to determine if abnormal processing extends to the conscious evaluation of emotional stimuli. Methods Functional Magnetic Resonance Imaging (fMRI) was used to examine brain activity as cannabis users (N=16) and non-cannabis using controls (N=17) evaluated and categorized standardized International Affective Picture System (IAPS) stimuli. Individual judgments were used to isolate activity during the evaluation of emotional (i.e., emotional evaluation) or neutral (i.e., neutral evaluation) stimuli. Within- and between-group analyses were performed. Results Both groups judged the same stimuli as emotional and had activations in visual, midbrain, and middle cingulate cortices during emotional evaluation, relative to neutral. Within-group analyses also revealed amygdalar and inferior frontal gyrus activations in controls, but not cannabis users, and medial prefrontal cortex (mPFC) deactivations in cannabis users, but not controls, during emotional evaluation, relative to neutral. Between-group comparisons found that mPFC activity during positive and negative evaluation was significantly hypoactive in cannabis users, relative to controls. Conclusions Abnormal neural processing of affective content extends to the level of consciousness in cannabis users. The hypoactive mPFC responses observed resembles the attenuated mPFC responses found during increased non-affective cognitive load in prior research. These findings suggest that abnormal mPFC singling in cannabis users during emotional evaluation might be associated with increased non-affective cognitive load. PMID:26690589

  1. Visual outcomes in children in Malawi following retinopathy of severe malaria.

    PubMed

    Beare, N A V; Southern, C; Kayira, K; Taylor, T E; Harding, S P

    2004-03-01

    To investigate whether retinal changes in children with severe malaria affect visual acuity 1 month after systemic recovery. All children with severe malaria admitted to a research ward in Malawi during one malaria season were examined by direct and indirect ophthalmoscopy. Visual acuity was tested in those attending follow up by Cardiff cards, Sheridan-Gardiner single letters, or Snellen chart. 96 (68%) children attended follow up, of whom 83 (86%) had visual acuity measured. Cardiff cards were used in 47 (57%) children, and Sheridan-Gardiner letters or Snellen chart in 29 (35%). There was no significant difference in the mean logMAR visual acuity between groups with or without macular whitening (0.14 versus 0.16, p = 0.55). There was no trend for worse visual acuity with increasing severity of macular whitening (p = 0.52) including patients in whom the fovea was involved (p = 0.32). Six (4.2%) children had cortical blindness after cerebral malaria, and all six had other neurological sequelae. Ophthalmoscopy during the acute illness revealed no abnormalities in four of these children. Retinal changes in severe malaria, in particular macular whitening, do not appear to affect visual acuity at 1 month. This supports the hypothesis that retinal whitening is due to reversible intracellular oedema in response to relative hypoxia, caused by sequestered erythrocytes infected by Plasmodium falciparum. Impaired visual functioning after cerebral malaria is not attributable to retinal changes and appears to be a cortical phenomenon.

  2. MR imaging of the fetal musculoskeletal system.

    PubMed

    Nemec, Stefan Franz; Nemec, Ursula; Brugger, Peter C; Bettelheim, Dieter; Rotmensch, Siegfried; Graham, John M; Rimoin, David L; Prayer, Daniela

    2012-03-01

    Magnetic resonance imaging (MRI) appears to be increasingly used, in addition to standard ultrasonography for the diagnosis of abnormalities in utero. Previous studies have recently drawn attention to the technical refinement of MRI to visualize the fetal bones and muscles. Beyond commonly used T2-weighted MRI, echoplanar, thick-slab T2-weighted and dynamic sequences, and three-dimensional MRI techniques, are about to provide new imaging insights into the normal and the pathological musculoskeletal system of the fetus. This review emphasizes the potential significance of MRI in the visualization of the fetal musculoskeletal system. © 2012 John Wiley & Sons, Ltd.

  3. Abnormal branching and regression of the notochord and its relationship to foregut abnormalities.

    PubMed

    Vleesch Dubois, V N; Quan Qi, B; Beasley, S W; Williams, A

    2002-04-01

    An abnormally positioned notochord has been reported in embryos that develop foregut abnormalities, vertebral defects and other abnormalities of the VATER association. This study examines the patterns of regression of the abnormal notochord in the rat model of the VATER association and investigates the relationship between developmental abnormalities of the notochord and those of the vertebra and foregut. Timed-pregnant Sprague-Dawley rats were given daily intraperitoneal injections of 1.75 mg/kg adriamycin on gestational days 6 - 9 inclusive. Rats were sacrificed between days 14 and 20 and their embryos harvested, histologically sectioned and stained and examined serially. The location and appearance of the degenerating notochord and its relationship to regional structural defects were analysed. All 26 embryos exposed to adriamycin developed foregut abnormalities and had an abnormal notochord. The notochord disappeared by a process of apoptotic degeneration that lagged behind that of the normal embryo: the notochord persisted in the abnormal embryo beyond day 17, whereas in the normal rat it had already disappeared. Similarly, formation of the nucleus pulposus was delayed. Vertebral abnormalities occurred when the notochord was ventrally-positioned. The notochord disappears during day 16 in the normal embryo whereas abnormal branches of the notochord persist until day 19 in the adriamycin-treated embryo. Degeneration of the notochord is dominated by apoptosis. An excessively ventrally-placed notochord is closely associated with abnormalities of the vertebral column, especially hemivertebrae.

  4. Visual examination apparatus

    NASA Technical Reports Server (NTRS)

    Haines, R. F.; Fitzgerald, J. W.; Rositano, S. A. (Inventor)

    1976-01-01

    An automated visual examination apparatus for measuring visual sensitivity and mapping blind spot location including a projection system for displaying to a patient a series of visual stimuli. A response switch enables him to indicate his reaction to the stimuli, and a recording system responsive to both the visual stimuli per se and the patient's response. The recording system thereby provides a correlated permanent record of both stimuli and response from which a substantive and readily apparent visual evaluation can be made.

  5. Computer-Aided Classification of Visual Ventilation Patterns in Patients with Chronic Obstructive Pulmonary Disease at Two-Phase Xenon-Enhanced CT

    PubMed Central

    Yoon, Soon Ho; Jung, Julip; Hong, Helen; Park, Eun Ah; Lee, Chang Hyun; Lee, Youkyung; Jin, Kwang Nam; Choo, Ji Yung; Lee, Nyoung Keun

    2014-01-01

    Objective To evaluate the technical feasibility, performance, and interobserver agreement of a computer-aided classification (CAC) system for regional ventilation at two-phase xenon-enhanced CT in patients with chronic obstructive pulmonary disease (COPD). Materials and Methods Thirty-eight patients with COPD underwent two-phase xenon ventilation CT with resulting wash-in (WI) and wash-out (WO) xenon images. The regional ventilation in structural abnormalities was visually categorized into four patterns by consensus of two experienced radiologists who compared the xenon attenuation of structural abnormalities with that of adjacent normal parenchyma in the WI and WO images, and it served as the reference. Two series of image datasets of structural abnormalities were randomly extracted for optimization and validation. The proportion of agreement on a per-lesion basis and receiver operating characteristics on a per-pixel basis between CAC and reference were analyzed for optimization. Thereafter, six readers independently categorized the regional ventilation in structural abnormalities in the validation set without and with a CAC map. Interobserver agreement was also compared between assessments without and with CAC maps using multirater κ statistics. Results Computer-aided classification maps were successfully generated in 31 patients (81.5%). The proportion of agreement and the average area under the curve of optimized CAC maps were 94% (75/80) and 0.994, respectively. Multirater κ value was improved from moderate (κ = 0.59; 95% confidence interval [CI], 0.56-0.62) at the initial assessment to excellent (κ = 0.82; 95% CI, 0.79-0.85) with the CAC map. Conclusion Our proposed CAC system demonstrated the potential for regional ventilation pattern analysis and enhanced interobserver agreement on visual classification of regional ventilation. PMID:24843245

  6. Computer-aided classification of visual ventilation patterns in patients with chronic obstructive pulmonary disease at two-phase xenon-enhanced CT.

    PubMed

    Yoon, Soon Ho; Goo, Jin Mo; Jung, Julip; Hong, Helen; Park, Eun Ah; Lee, Chang Hyun; Lee, Youkyung; Jin, Kwang Nam; Choo, Ji Yung; Lee, Nyoung Keun

    2014-01-01

    To evaluate the technical feasibility, performance, and interobserver agreement of a computer-aided classification (CAC) system for regional ventilation at two-phase xenon-enhanced CT in patients with chronic obstructive pulmonary disease (COPD). Thirty-eight patients with COPD underwent two-phase xenon ventilation CT with resulting wash-in (WI) and wash-out (WO) xenon images. The regional ventilation in structural abnormalities was visually categorized into four patterns by consensus of two experienced radiologists who compared the xenon attenuation of structural abnormalities with that of adjacent normal parenchyma in the WI and WO images, and it served as the reference. Two series of image datasets of structural abnormalities were randomly extracted for optimization and validation. The proportion of agreement on a per-lesion basis and receiver operating characteristics on a per-pixel basis between CAC and reference were analyzed for optimization. Thereafter, six readers independently categorized the regional ventilation in structural abnormalities in the validation set without and with a CAC map. Interobserver agreement was also compared between assessments without and with CAC maps using multirater κ statistics. Computer-aided classification maps were successfully generated in 31 patients (81.5%). The proportion of agreement and the average area under the curve of optimized CAC maps were 94% (75/80) and 0.994, respectively. Multirater κ value was improved from moderate (κ = 0.59; 95% confidence interval [CI], 0.56-0.62) at the initial assessment to excellent (κ = 0.82; 95% CI, 0.79-0.85) with the CAC map. Our proposed CAC system demonstrated the potential for regional ventilation pattern analysis and enhanced interobserver agreement on visual classification of regional ventilation.

  7. Development of the navigation system for visually impaired.

    PubMed

    Harada, Tetsuya; Kaneko, Yuki; Hirahara, Yoshiaki; Yanashima, Kenji; Magatani, Kazushige

    2004-01-01

    A white cane is a typical support instrument for the visually impaired. They use a white cane for the detection of obstacles while walking. So, the area where they have a mental map, they can walk using white cane without the help of others. However, they cannot walk independently in the unknown area, even if they use a white cane. Because, a white cane is a detecting device for obstacles and not a navigation device for their correct route. Now, we are developing the navigation system for the visually impaired which uses indoor space. In Japan, sometimes colored guide lines to the destination is used for a normal person. These lines are attached on the floor, we can reach the destination, if we walk along one of these line. In our system, a developed new white cane senses one colored guide line, and make notice to an user by vibration. This system recognizes the line of the color stuck on the floor by the optical sensor attached in the white cane. And in order to guide still more smoothly, infrared beacons (optical beacon), which can perform voice guidance, are also used.

  8. The Modulation of Visual and Task Characteristics of a Writing System on Hemispheric Lateralization in Visual Word Recognition--A Computational Exploration

    ERIC Educational Resources Information Center

    Hsiao, Janet H.; Lam, Sze Man

    2013-01-01

    Through computational modeling, here we examine whether visual and task characteristics of writing systems alone can account for lateralization differences in visual word recognition between different languages without assuming influence from left hemisphere (LH) lateralized language processes. We apply a hemispheric processing model of face…

  9. Causes and anatomical site of blindness and severe visual loss in Isfahan, Islamic Republic of Iran.

    PubMed

    Dehghan, A; Kianersi, F; Moazam, E; Ghanbari, H

    2010-02-01

    This study in 2005 evaluated the causes and major anatomical site of blindness and severe visual loss at a school for blind children in Isfahan province, Islamic Republic of Iran. All 211 students were examined according to the modified WHO/PBL eye examination record: 70.4% were blind, 24.3% had severe visual loss and 5.3% were visually impaired. The major causes of abnormality were hereditary factors (42.7%), prenatal/neonatal (18.5%) and unknown etiology (35.5%). The main sites of abnormality were the retina (62.6%), whole globe (17.5%), lens (7.1%) and optic nerve (7.1%). A high proportion of parents were in a consanguineous marriage (49.2%). The pattern of blindness in Isfahan encompasses characteristics of both developed and developing countries.

  10. Improving visual observation skills through the arts to aid radiographic interpretation in veterinary practice: A pilot study.

    PubMed

    Beck, Cathy; Gaunt, Heather; Chiavaroli, Neville

    2017-09-01

    Radiographic interpretation is a perceptual and cognitive skill. Recently core veterinary radiology textbooks have focused on the cognitive (i.e., the clinical aspects of radiographic interpretation) rather than the features of visual observation that improve identification of abnormalities. As a result, the skill of visual observation is underemphasized and thus often underdeveloped by trainees. The study of the arts in medical education has been used to train and improve visual observation and empathy. The use of the arts to improve visual observation skills in Veterinary Science has not been previously described. Objectives of this pilot study were to adapt the existing Visual Arts in Health Education Program for medical and dental students at the University of Melbourne, Australia to third year Doctor of Veterinary Medicine students and evaluate their perceptions regarding the program's effects on visual observation skills and confidence with respect to radiographic interpretation. This adaptation took the form of a single seminar given to third year Doctor of Veterinary Medicine students. Following the seminar, students reported an improved approach to radiographic interpretation and felt they had gained skills which would assist them throughout their career. In the year following the seminar, written reports of the students who attended the seminar were compared with reports from a matched cohort of students who did not attend the seminar. This demonstrated increased identification of abnormalities and greater description of the abnormalities identified. Findings indicated that explicit training in visual observation may be a valuable adjunct to the radiology training of Doctor of Veterinary Medicine students. © 2017 American College of Veterinary Radiology.

  11. Smart-system of distance learning of visually impaired people based on approaches of artificial intelligence

    NASA Astrophysics Data System (ADS)

    Samigulina, Galina A.; Shayakhmetova, Assem S.

    2016-11-01

    Research objective is the creation of intellectual innovative technology and information Smart-system of distance learning for visually impaired people. The organization of the available environment for receiving quality education for visually impaired people, their social adaptation in society are important and topical issues of modern education.The proposed Smart-system of distance learning for visually impaired people can significantly improve the efficiency and quality of education of this category of people. The scientific novelty of proposed Smart-system is using intelligent and statistical methods of processing multi-dimensional data, and taking into account psycho-physiological characteristics of perception and awareness learning information by visually impaired people.

  12. Role of Visual Feedback Treatment for Defective /s/ Sounds in Patients with Cleft Palate.

    ERIC Educational Resources Information Center

    Michi, Ken-ichi; And Others

    1993-01-01

    Six patients with cleft palate were provided treatment using either visual feedback for tongue placement and frication or no visual feedback. Results indicated the feedback was especially useful in the treatment of defective /s/ sounds in the patients who exhibited abnormal posterior tongue posturing during dental or alveolar sounds. (Author/DB)

  13. Usability Evaluation of a Flight-Deck Airflow Hazard Visualization System

    NASA Technical Reports Server (NTRS)

    Aragon, Cecilia R.

    2004-01-01

    Many aircraft accidents each year are caused by encounters with unseen airflow hazards near the ground, such as vortices, downdrafts, low level wind shear, microbursts, or turbulence from surrounding vegetation or structures near the landing site. These hazards can be dangerous even to airliners; there have been hundreds of fatalities in the United States in the last two decades attributable to airliner encounters with microbursts and low level wind shear alone. However, helicopters are especially vulnerable to airflow hazards because they often have to operate in confined spaces and under operationally stressful conditions (such as emergency search and rescue, military or shipboard operations). Providing helicopter pilots with an augmented-reality display visualizing local airflow hazards may be of significant benefit. However, the form such a visualization might take, and whether it does indeed provide a benefit, had not been studied before our experiment. We recruited experienced military and civilian helicopter pilots for a preliminary usability study to evaluate a prototype augmented-reality visualization system. The study had two goals: first, to assess the efficacy of presenting airflow data in flight; and second, to obtain expert feedback on sample presentations of hazard indicators to refine our design choices. The study addressed the optimal way to provide critical safety information to the pilot, what level of detail to provide, whether to display specific aerodynamic causes or potential effects only, and how to safely and effectively shift the locus of attention during a high-workload task. Three-dimensional visual cues, with varying shape, color, transparency, texture, depth cueing, and use of motion, depicting regions of hazardous airflow, were developed and presented to the pilots. The study results indicated that such a visualization system could be of significant value in improving safety during critical takeoff and landing operations, and also

  14. Abnormal Sleep/Wake Dynamics in Orexin Knockout Mice

    PubMed Central

    Diniz Behn, Cecilia G.; Klerman, Elizabeth B.; Mochizuki, Takatoshi; Lin, Shih-Chieh; Scammell, Thomas E.

    2010-01-01

    Study Objectives: Narcolepsy with cataplexy is caused by a loss of orexin (hypocretin) signaling, but the physiologic mechanisms that result in poor maintenance of wakefulness and fragmented sleep remain unknown. Conventional scoring of sleep cannot reveal much about the process of transitioning between states or the variations within states. We developed an EEG spectral analysis technique to determine whether the state instability in a mouse model of narcolepsy reflects abnormal sleep or wake states, faster movements between states, or abnormal transitions between states. Design: We analyzed sleep recordings in orexin knockout (OXKO) mice and wild type (WT) littermates using a state space analysis technique. This non-categorical approach allows quantitative and unbiased examination of sleep/wake states and state transitions. Measurements and Results: OXKO mice spent less time in deep, delta-rich NREM sleep and in active, theta-rich wake and instead spent more time near the transition zones between states. In addition, while in the midst of what should be stable wake, OXKO mice initiated rapid changes into NREM sleep with high velocities normally seen only in transition regions. Consequently, state transitions were much more frequent and rapid even though the EEG progressions during state transitions were normal. Conclusions: State space analysis enables visualization of the boundaries between sleep and wake and shows that narcoleptic mice have less distinct and more labile states of sleep and wakefulness. These observations provide new perspectives on the abnormal state dynamics resulting from disrupted orexin signaling and highlight the usefulness of state space analysis in understanding narcolepsy and other sleep disorders. Citation: Diniz Behn CG; Klerman EB; Mochizuki T; Lin S; Scammell TE. Abnormal sleep/wake dynamics in orexin knockout mice. SLEEP 2010;33(3):297-306. PMID:20337187

  15. Visual examination apparatus

    NASA Technical Reports Server (NTRS)

    Haines, R. F.; Fitzgerald, J. W.; Rositano, S. A. (Inventor)

    1973-01-01

    An automated visual examination apparatus for measuring visual sensitivity and mapping blind spot location is described. The apparatus includes a projection system for displaying to a patient a series of visual stimuli, a response switch enabling him to indicate his reaction to the stimuli, and a recording system responsive to both the visual stimuli per se and the patient's response. The recording system provides a correlated permanent record of both stimuli and response from which a substantive and readily apparent visual evaluation can be made.

  16. An Avatar-Based Italian Sign Language Visualization System

    NASA Astrophysics Data System (ADS)

    Falletto, Andrea; Prinetto, Paolo; Tiotto, Gabriele

    In this paper, we present an experimental system that supports the translation from Italian to Italian Sign Language (ISL) of the deaf and its visualization through a virtual character. Our objective is to develop a complete platform useful for any application and reusable on several platforms including Web, Digital Television and offline text translation. The system relies on a database that stores both a corpus of Italian words and words coded in the ISL notation system. An interface for the insertion of data is implemented, that allows future extensions and integrations.

  17. Follow-Up of Abnormal Breast and Colorectal Cancer Screening by Race/Ethnicity.

    PubMed

    McCarthy, Anne Marie; Kim, Jane J; Beaber, Elisabeth F; Zheng, Yingye; Burnett-Hartman, Andrea; Chubak, Jessica; Ghai, Nirupa R; McLerran, Dale; Breen, Nancy; Conant, Emily F; Geller, Berta M; Green, Beverly B; Klabunde, Carrie N; Inrig, Stephen; Skinner, Celette Sugg; Quinn, Virginia P; Haas, Jennifer S; Schnall, Mitchell; Rutter, Carolyn M; Barlow, William E; Corley, Douglas A; Armstrong, Katrina; Doubeni, Chyke A

    2016-10-01

    Timely follow-up of abnormal tests is critical to the effectiveness of cancer screening, but may vary by screening test, healthcare system, and sociodemographic group. Timely follow-up of abnormal mammogram and fecal occult blood testing or fecal immunochemical tests (FOBT/FIT) were compared by race/ethnicity using Population-Based Research Optimizing Screening through Personalized Regimens consortium data. Participants were women with an abnormal mammogram (aged 40-75 years) or FOBT/FIT (aged 50-75 years) in 2010-2012. Analyses were performed in 2015. Timely follow-up was defined as colonoscopy ≤3 months following positive FOBT/FIT; additional imaging or biopsy ≤3 months following Breast Imaging Reporting and Data System Category 0, 4, or 5 mammograms; or ≤9 months following Category 3 mammograms. Logistic regression was used to model receipt of timely follow-up adjusting for study site, age, year, insurance, and income. Among 166,602 mammograms, 10.7% were abnormal; among 566,781 FOBT/FITs, 4.3% were abnormal. Nearly 96% of patients with abnormal mammograms received timely follow-up versus 68% with abnormal FOBT/FIT. There was greater variability in receipt of follow-up across healthcare systems for positive FOBT/FIT than for abnormal mammograms. For mammography, black women were less likely than whites to receive timely follow-up (91.8% vs 96.0%, OR=0.71, 95% CI=0.51, 0.97). For FOBT/FIT, Hispanics were more likely than whites to receive timely follow-up than whites (70.0% vs 67.6%, OR=1.12, 95% CI=1.04, 1.21). Timely follow-up among women was more likely for abnormal mammograms than FOBT/FITs, with small variations in follow-up rates by race/ethnicity and larger variation across healthcare systems. Copyright © 2016 American Journal of Preventive Medicine. All rights reserved.

  18. The accuracy of ultrasound in the diagnosis of congenital abnormalities.

    PubMed

    Munim, Shama; Nadeem, Salva; Khuwaja, Nadya Ali

    2006-01-01

    To determine the accuracy of ultrasound in the diagnosis of congenital abnormalities at the Aga Khan University Hospital, Karachi. The data of congenital abnormalities was obtained from the obstetrical database and medical records of all cases complicated by congenital abnormalities, delivering from January 2001 to December 2003 and was reviewed. Antenatal ultrasounds had been performed by operators with different level of experience. In addition this data was retrieved from the termination and Congenital anomaly register. A structured data collection form was used to collect information of different variables of interest. Congenital abnormalities, complicated 2.8% (n=170), of all deliveries, including all cases of termination of pregnancy, stillbirth and live births. Out of the total, 11.6% occurred in women above the age of 35 years. Consanguinity was found in 18.2% cases. Prenatal diagnosis was made in just under half of the cases (48.8%). Central nervous system and renal abnormalities were commonly diagnosed. However, facial defects, heart defects or skeletal defects were more commonly missed. Antenatal ultrasound successfully diagnosed foetal abnormalities in 48.8% of cases, and more than 90% Central Nervous system defects and renal abnormalities. In contrast about a quarter of Cardiac defects and none of the facial defects were detected. Based on these findings we recommend that the Sonologist should incorporate four chamber view of the heart and also look at the face carefully.

  19. Needle tip visualization by bevel-point ultrasound generator and prototype photoacoustic imaging system

    NASA Astrophysics Data System (ADS)

    Irisawa, Kaku; Murakoshi, Dai; Hashimoto, Atsushi; Yamamoto, Katsuya; Hayakawa, Toshiro

    2017-03-01

    Visualization of the tip of medical devices like needles or catheters under ultrasound imaging has been a continuous topic since the early 1980's. In this study, a needle tip visualization system utilizing photoacoustic effects is proposed. In order to visualize the needle tip, an optical fiber was inserted into a needle. The optical fiber tip is placed on the needle bevel and affixed with black glue. The pulsed laser light from laser diode was transferred to the optical fiber and converted to ultrasound due to laser light absorption of the black glue and the subsequent photoacoustic effect. The ultrasound is detected by transducer array and reconstructed into photoacoustic images in the ultrasound unit. The photoacoustic image is displayed with a superposed ultrasound B-mode image. As a system evaluation, the needle is punctured into bovine meat and the needle tip is observed with commercialized conventional linear transducers or convex transducers. The needle tip is visualized clearly at 7 and 12 cm depths with linear and convex probes, respectively, even with a steep needle puncture angle of around 90 degrees. Laser and acoustic outputs, and thermal rise at the needle tip, were measured and were well below the limits of the safety standards. Compared with existing needle tip visualization technologies, the photoacoustic needle tip visualization system has potential distinguishable features for clinical procedures related with needle puncture and injection.

  20. Neural network system for purposeful behavior based on foveal visual preprocessor

    NASA Astrophysics Data System (ADS)

    Golovan, Alexander V.; Shevtsova, Natalia A.; Klepatch, Arkadi A.

    1996-10-01

    Biologically plausible model of the system with an adaptive behavior in a priori environment and resistant to impairment has been developed. The system consists of input, learning, and output subsystems. The first subsystems classifies input patterns presented as n-dimensional vectors in accordance with some associative rule. The second one being a neural network determines adaptive responses of the system to input patterns. Arranged neural groups coding possible input patterns and appropriate output responses are formed during learning by means of negative reinforcement. Output subsystem maps a neural network activity into the system behavior in the environment. The system developed has been studied by computer simulation imitating a collision-free motion of a mobile robot. After some learning period the system 'moves' along a road without collisions. It is shown that in spite of impairment of some neural network elements the system functions reliably after relearning. Foveal visual preprocessor model developed earlier has been tested to form a kind of visual input to the system.

  1. Thermodynamic properties of gas-condensate system with abnormally high content of heavy hydrocarbons

    NASA Astrophysics Data System (ADS)

    Zanochuev, S. A.; Shabarov, A. B.; Podorozhnikov, S. Yu; Zakharov, A. A.

    2018-05-01

    Gas-condensate systems (GCS) with an abnormally high content of heavy hydrocarbons are characterized by a sharp change in both phase and component compositions with an insignificant decrease in pressure below the start pressure of the phase transitions (the beginning of condensation). Calculation methods for describing the phase behavior of such systems are very sensitive to the quality of the initial information. The uncertainty of the input data leads not only to significant errors in the forecast of phase compositions, but also to an incorrect phase state estimation of the whole system. The research presents the experimental thermodynamic parameters of the GCS of the BT reservoirs on the Beregovoye field, obtained at the phase equilibrium facility. The data contribute to the adaptation of the calculated models of the phase behavior of the GCS with a change in pressure.

  2. Exomars VisLoc- The Visual Localisation System for the Exomars Rover

    NASA Astrophysics Data System (ADS)

    Ward, R.; Hamilton, W.; Silva, N.; Pereira, V.

    2016-08-01

    Maintaining accurate knowledge of the current position of vehicles on the surface of Mars is a considerable problem. The lack of an orbital GPS means that the absolute position of a rover at any instant is very difficult to determine, and with that it is difficult to accurately and safely plan hazard avoidance manoeuvres.Some on-board methods of determining the evolving POSE of a rover are well known, such as using wheel odometry to keep a log of the distance travelled. However there are associated problems - wheels can slip in the martial soil providing odometry readings which can mislead navigation algorithms. One solution to this is to use a visual localisation system, which uses cameras to determine the actual rover motion from images of the terrain. By measuring movement from the terrain an independent measure of the actual movement can be obtained to a high degree of accuracy.This paper presents the progress of the project to develop a the Visual Localisation system for the ExoMars rover (VisLoc). The core algorithmm used in the system is known as OVO (Oxford Visual Odometry), developed at the Mobile Robotics Group at the University of Oxford. Over a number of projects this system has been adapted from its original purpose (navigation systems for autonomous vehicles) to be a viable system for the unique challenges associated with extra-terrestrial use.

  3. Head Worn Display System for Equivalent Visual Operations

    NASA Technical Reports Server (NTRS)

    Cupero, Frank; Valimont, Brian; Wise, John; Best. Carl; DeMers, Bob

    2009-01-01

    Head-Worn Displays or so-called, near-to-eye displays have potentially significant advantages in terms of cost, overcoming cockpit space constraints, and for the display of spatially-integrated information. However, many technical issues need to be overcome before these technologies can be successfully introduced into commercial aircraft cockpits. The results of three activities are reported. First, the near-to-eye display design, technological, and human factors issues are described and a literature review is presented. Second, the results of a fixed-base piloted simulation, investigating the impact of near to eye displays on both operational and visual performance is reported. Straight-in approaches were flown in simulated visual and instrument conditions while using either a biocular or a monocular display placed on either the dominant or non-dominant eye. The pilot's flight performance, visual acuity, and ability to detect unsafe conditions on the runway were tested. The data generally supports a monocular design with minimal impact due to eye dominance. Finally, a method for head tracker system latency measurement is developed and used to compare two different devices.

  4. Assisting the visually impaired: obstacle detection and warning system by acoustic feedback.

    PubMed

    Rodríguez, Alberto; Yebes, J Javier; Alcantarilla, Pablo F; Bergasa, Luis M; Almazán, Javier; Cela, Andrés

    2012-12-17

    The aim of this article is focused on the design of an obstacle detection system for assisting visually impaired people. A dense disparity map is computed from the images of a stereo camera carried by the user. By using the dense disparity map, potential obstacles can be detected in 3D in indoor and outdoor scenarios. A ground plane estimation algorithm based on RANSAC plus filtering techniques allows the robust detection of the ground in every frame. A polar grid representation is proposed to account for the potential obstacles in the scene. The design is completed with acoustic feedback to assist visually impaired users while approaching obstacles. Beep sounds with different frequencies and repetitions inform the user about the presence of obstacles. Audio bone conducting technology is employed to play these sounds without interrupting the visually impaired user from hearing other important sounds from its local environment. A user study participated by four visually impaired volunteers supports the proposed system.

  5. A Conserved Developmental Mechanism Builds Complex Visual Systems in Insects and Vertebrates

    PubMed Central

    Joly, Jean-Stéphane; Recher, Gaelle; Brombin, Alessandro; Ngo, Kathy; Hartenstein, Volker

    2016-01-01

    The visual systems of vertebrates and many other bilaterian clades consist of complex neural structures guiding a wide spectrum of behaviors. Homologies at the level of cell types and even discrete neural circuits have been proposed, but many questions of how the architecture of visual neuropils evolved among different phyla remain open. In this review we argue that the profound conservation of genetic and developmental steps generating the eye and its target neuropils in fish and fruit flies supports a homology between some core elements of bilaterian visual circuitries. Fish retina and tectum, and fly optic lobe, develop from a partitioned, unidirectionally proliferating neurectodermal domain that combines slowly dividing neuroepithelial stem cells and rapidly amplifying progenitors with shared genetic signatures to generate large numbers and different types of neurons in a temporally ordered way. This peculiar ‘conveyor belt neurogenesis’ could play an essential role in generating the topographically ordered circuitry of the visual system. PMID:27780043

  6. Assisting the Visually Impaired: Obstacle Detection and Warning System by Acoustic Feedback

    PubMed Central

    Rodríguez, Alberto; Yebes, J. Javier; Alcantarilla, Pablo F.; Bergasa, Luis M.; Almazán, Javier; Cela, Andrés

    2012-01-01

    The aim of this article is focused on the design of an obstacle detection system for assisting visually impaired people. A dense disparity map is computed from the images of a stereo camera carried by the user. By using the dense disparity map, potential obstacles can be detected in 3D in indoor and outdoor scenarios. A ground plane estimation algorithm based on RANSAC plus filtering techniques allows the robust detection of the ground in every frame. A polar grid representation is proposed to account for the potential obstacles in the scene. The design is completed with acoustic feedback to assist visually impaired users while approaching obstacles. Beep sounds with different frequencies and repetitions inform the user about the presence of obstacles. Audio bone conducting technology is employed to play these sounds without interrupting the visually impaired user from hearing other important sounds from its local environment. A user study participated by four visually impaired volunteers supports the proposed system. PMID:23247413

  7. A Spot Reminder System for the Visually Impaired Based on a Smartphone Camera

    PubMed Central

    Takizawa, Hotaka; Orita, Kazunori; Aoyagi, Mayumi; Ezaki, Nobuo; Mizuno, Shinji

    2017-01-01

    The present paper proposes a smartphone-camera-based system to assist visually impaired users in recalling their memories related to important locations, called spots, that they visited. The memories are recorded as voice memos, which can be played back when the users return to the spots. Spot-to-spot correspondence is determined by image matching based on the scale invariant feature transform. The main contribution of the proposed system is to allow visually impaired users to associate arbitrary voice memos with arbitrary spots. The users do not need any special devices or systems except smartphones and do not need to remember the spots where the voice memos were recorded. In addition, the proposed system can identify spots in environments that are inaccessible to the global positioning system. The proposed system has been evaluated by two experiments: image matching tests and a user study. The experimental results suggested the effectiveness of the system to help visually impaired individuals, including blind individuals, recall information about regularly-visited spots. PMID:28165403

  8. Measuring the Influence of Galilean Loupe System on Near Visual Acuity of Dentists under Simulated Clinical Conditions

    PubMed Central

    Urlic, Iris; Verzak, Željko; Vranic, Dubravka Negovetic

    2016-01-01

    Aim The purpose of this study was to compare near visual acuity of dentists without optical aids (VSC) with near visual acuity of those using the Galilean telescope system (VGA2) with magnification of x 2.5, and the distance of 350 mm in simulated clinical conditions. Methods The study included 46 dentists (visual acuity 1.0 without correction). A visual acuity testing was carried out using a miniaturized Snellen visual acuity chart which was placed in the cavity of molar teeth mounted in a phantom head in simulated clinical conditions. Near visual acuity for the vicinity was examined: 1) without correction at a distance of 300-400 mm (VSC); 2) with Galilean loupes with magnification of x2.5, focal length of 350mm. Results The distributions of near visual acuity recorded using VSC and VGA2, 5 systems were compared by the Wilcoxon Signed Rank test. The results obtained by Wilcoxon Signed Rank test pointed to a statistically significant difference in the distribution of recorded visual acuity between the VSC and VGA2 optical systems (W = - 403.5; p <0.001). Conclusion If using the VGA2, 5 systems, higher values of the near visual acuity were recorded and subsequently compared to near visual acuity without magnifying aids (VSC). PMID:27847397

  9. Measuring the Influence of Galilean Loupe System on Near Visual Acuity of Dentists under Simulated Clinical Conditions.

    PubMed

    Urlic, Iris; Verzak, Željko; Vranic, Dubravka Negovetic

    2016-09-01

    The purpose of this study was to compare near visual acuity of dentists without optical aids (VSC) with near visual acuity of those using the Galilean telescope system (VGA2) with magnification of x 2.5, and the distance of 350 mm in simulated clinical conditions. The study included 46 dentists (visual acuity 1.0 without correction). A visual acuity testing was carried out using a miniaturized Snellen visual acuity chart which was placed in the cavity of molar teeth mounted in a phantom head in simulated clinical conditions. Near visual acuity for the vicinity was examined: 1) without correction at a distance of 300-400 mm (VSC); 2) with Galilean loupes with magnification of x2.5, focal length of 350mm. The distributions of near visual acuity recorded using VSC and VGA2, 5 systems were compared by the Wilcoxon Signed Rank test. The results obtained by Wilcoxon Signed Rank test pointed to a statistically significant difference in the distribution of recorded visual acuity between the VSC and VGA2 optical systems (W = - 403.5; p <0.001). If using the VGA2, 5 systems, higher values of the near visual acuity were recorded and subsequently compared to near visual acuity without magnifying aids (VSC).

  10. [Characteristics of pregnancy and delivery of fetuses affected by either central nervous system malformations or chromosomal abnormalities].

    PubMed

    Friedler, Jordana Mashiach; Mazor, Moshe; Shoham-Vardi, Ilana; Bashiri, Asher

    2011-11-01

    To determine whether fetuses affected by either chromosomal abnormalities or central nervous system (CNS) malformations are prone to complications during pregnancy and delivery. In this study, 320 singleton pregnancies with CNS malformations and 133 singleton pregnancies with chromosomal abnormaLities were compared with 149,112 singleton births without any known congenital anomalies. Exclusion criteria were: births with other congenital anomalies or malformations, pregnancies Lacking prenatal care and multiple pregnancies. Data was obtained using the computerized birth discharge records. The statistical analysis was performed with the SPSS package. There were no statistically significant differences in maternal age, ethnicity, uterine anomalies or parity. The ratio of general anesthesia was almost double in the study groups compared to the control group: 25% in the CNS malformation group (RR 2.617, CI 2.031-3.372) and 25.6% in the chromosomal abnormality group (RR 2.696, CI 1.825-3.982) and 11.3% in the control group (p < 0.001). There were nearly double cesarean sections (CS) rates in both study groups: 21.5% in the CNS malformation group, 20.3% in the chromosomal abnormaLity group and 12% in the control group. A logistic regression model that included previous CS, maLpresentation, non-reassuring fetal heart monitor (NRFHR) and presence of a malformation, concluded that the presence of a malformation was not an independent risk factor for CS. However, indirect causes, such as malpresentation (4.34 OR), were independently associated with the malformations. Fetuses affected by either CNS malformations or chromosomal abnormalities have a higher rate of pregnancy and delivery complications, including those which increase the risk of maternal morbidity and mortality.

  11. Abnormal regional cerebral blood flow in childhood autism.

    PubMed

    Ohnishi, T; Matsuda, H; Hashimoto, T; Kunihiro, T; Nishikawa, M; Uema, T; Sasaki, M

    2000-09-01

    Neuroimaging studies of autism have shown abnormalities in the limbic system and cerebellar circuits and additional sites. These findings are not, however, specific or consistent enough to build up a coherent theory of the origin and nature of the brain abnormality in autistic patients. Twenty-three children with infantile autism and 26 non-autistic controls matched for IQ and age were examined using brain-perfusion single photon emission computed tomography with technetium-99m ethyl cysteinate dimer. In autistic subjects, we assessed the relationship between regional cerebral blood flow (rCBF) and symptom profiles. Images were anatomically normalized, and voxel-by-voxel analyses were performed. Decreases in rCBF in autistic patients compared with the control group were identified in the bilateral insula, superior temporal gyri and left prefrontal cortices. Analysis of the correlations between syndrome scores and rCBF revealed that each syndrome was associated with a specific pattern of perfusion in the limbic system and the medial prefrontal cortex. The results confirmed the associations of (i) impairments in communication and social interaction that are thought to be related to deficits in the theory of mind (ToM) with altered perfusion in the medial prefrontal cortex and anterior cingulate gyrus, and (ii) the obsessive desire for sameness with altered perfusion in the right medial temporal lobe. The perfusion abnormalities seem to be related to the cognitive dysfunction observed in autism, such as deficits in ToM, abnormal responses to sensory stimuli, and the obsessive desire for sameness. The perfusion patterns suggest possible locations of abnormalities of brain function underlying abnormal behaviour patterns in autistic individuals.

  12. Visual system plasticity in mammals: the story of monocular enucleation-induced vision loss

    PubMed Central

    Nys, Julie; Scheyltjens, Isabelle; Arckens, Lutgarde

    2015-01-01

    The groundbreaking work of Hubel and Wiesel in the 1960’s on ocular dominance plasticity instigated many studies of the visual system of mammals, enriching our understanding of how the development of its structure and function depends on high quality visual input through both eyes. These studies have mainly employed lid suturing, dark rearing and eye patching applied to different species to reduce or impair visual input, and have created extensive knowledge on binocular vision. However, not all aspects and types of plasticity in the visual cortex have been covered in full detail. In that regard, a more drastic deprivation method like enucleation, leading to complete vision loss appears useful as it has more widespread effects on the afferent visual pathway and even on non-visual brain regions. One-eyed vision due to monocular enucleation (ME) profoundly affects the contralateral retinorecipient subcortical and cortical structures thereby creating a powerful means to investigate cortical plasticity phenomena in which binocular competition has no vote.In this review, we will present current knowledge about the specific application of ME as an experimental tool to study visual and cross-modal brain plasticity and compare early postnatal stages up into adulthood. The structural and physiological consequences of this type of extensive sensory loss as documented and studied in several animal species and human patients will be discussed. We will summarize how ME studies have been instrumental to our current understanding of the differentiation of sensory systems and how the structure and function of cortical circuits in mammals are shaped in response to such an extensive alteration in experience. In conclusion, we will highlight future perspectives and the clinical relevance of adding ME to the list of more longstanding deprivation models in visual system research. PMID:25972788

  13. Audiovisual plasticity following early abnormal visual experience: Reduced McGurk effect in people with one eye.

    PubMed

    Moro, Stefania S; Steeves, Jennifer K E

    2018-04-13

    Previously, we have shown that people who have had one eye surgically removed early in life during visual development have enhanced sound localization [1] and lack visual dominance, commonly observed in binocular and monocular (eye-patched) viewing controls [2]. Despite these changes, people with one eye integrate auditory and visual components of multisensory events optimally [3]. The current study investigates how people with one eye perceive the McGurk effect, an audiovisual illusion where a new syllable is perceived when visual lip movements do not match the corresponding sound [4]. We compared individuals with one eye to binocular and monocular viewing controls and found that they have a significantly smaller McGurk effect compared to binocular controls. Additionally, monocular controls tended to perceive the McGurk effect less often than binocular controls suggesting a small transient modulation of the McGurk effect. These results suggest altered weighting of the auditory and visual modalities with both short and long-term monocular viewing. These results indicate the presence of permanent adaptive perceptual accommodations in people who have lost one eye early in life that may serve to mitigate the loss of binocularity during early brain development. Crown Copyright © 2018. Published by Elsevier B.V. All rights reserved.

  14. Visual perception system and method for a humanoid robot

    NASA Technical Reports Server (NTRS)

    Chelian, Suhas E. (Inventor); Linn, Douglas Martin (Inventor); Wampler, II, Charles W. (Inventor); Bridgwater, Lyndon (Inventor); Wells, James W. (Inventor); Mc Kay, Neil David (Inventor)

    2012-01-01

    A robotic system includes a humanoid robot with robotic joints each moveable using an actuator(s), and a distributed controller for controlling the movement of each of the robotic joints. The controller includes a visual perception module (VPM) for visually identifying and tracking an object in the field of view of the robot under threshold lighting conditions. The VPM includes optical devices for collecting an image of the object, a positional extraction device, and a host machine having an algorithm for processing the image and positional information. The algorithm visually identifies and tracks the object, and automatically adapts an exposure time of the optical devices to prevent feature data loss of the image under the threshold lighting conditions. A method of identifying and tracking the object includes collecting the image, extracting positional information of the object, and automatically adapting the exposure time to thereby prevent feature data loss of the image.

  15. Prevalence of macular abnormalities assessed by optical coherence tomography in patients with Usher syndrome.

    PubMed

    Testa, Francesco; Melillo, Paolo; Rossi, Settimio; Marcelli, Vincenzo; de Benedictis, Antonella; Colucci, Raffaella; Gallo, Beatrice; Brunetti-Pierri, Raffaella; Donati, Simone; Azzolini, Claudio; Marciano, Elio; Simonelli, Francesca

    2018-01-01

    To investigate the prevalence of macular abnormalities in patients affected by Usher syndrome (USH), by comparing the clinical findings between two types (i.e., USH1 and USH2). A retrospective study was performed by reviewing optical coherence tomography (OCT) in 134 USH patients to determine the presence of macular abnormalities, including cystoid macular edema (CME), epiretinal membrane (ERM), vitreo-macular traction syndrome (VMT), and macular hole (MH). Macular abnormalities were observed in 126/268 (47.0%) examined eyes. The most frequent abnormality was ERM observed in 51 eyes (19%), followed by CME observed in 42 eyes (15.7%). Moreover, CME was significantly (p < 0.05) associated with younger age (CME: 30.1 ± 11.1 years; without CME: 36.9 ± 14.9 years), whereas VMT and full thickness MH were associated with older age (p < 0.05). Moreover, a significantly (p < 0.05) decreased best-corrected visual acuity was associated with MH compared to eyes without MH. Finally, CME was more frequent in USH1 compared to USH2. Our study, for the first time in the literature, showed the distribution of all macular abnormalities assessed by SD-OCT in a large USH cohort, comparing USH1 and USH2 patients. We observed that ocular abnormalities are highly prevalent in USH patients compared to general population, with ERM and CME being the most common alterations. Based on these findings, OCT screening in USH patients is recommended for early detection of macular changes and early treatment.

  16. Abnormal uterine bleeding in reproductive-aged women.

    PubMed

    Matthews, Michelle L

    2015-03-01

    Abnormal uterine bleeding is a common medical condition with several causes. The International Federation of Gynecology and Obstetrics published guidelines in 2011 to develop universally accepted nomenclature and a classification system. In addition, the American College of Obstetrics and Gynecology recently updated recommendations on evaluation of abnormal uterine bleeding and indications for endometrial biopsies. This article reviews both medical and surgical treatments, including meta-analysis reviews of the most effective treatment options. Copyright © 2015 Elsevier Inc. All rights reserved.

  17. Evaluation of central nervous system in patients with glycogen storage disease type 1a.

    PubMed

    Aydemir, Yusuf; Gürakan, Figen; Saltık Temizel, İnci Nur; Demir, Hülya; Oğuz, Kader Karlı; Yalnızoğlu, Dilek; Topçu, Meral; Özen, Hasan; Yüce, Aysel

    2016-01-01

    We aimed to evaluate structure and functions of central nervous system (CNS) in children with glycogen storage disease (GSD) type 1a. Neurological examination, psychometric tests, electroencephalography (EEG), magnetic resonance imaging (MRI), visual evoked potentials (VEP) and brainstem auditory evoked potentials (BAEP) were performed. The results were compared between patients with good and poor metabolic control and healthy children. Twenty-three patients with GSD type 1a were studied. Twelve patients were in poor metabolic control group and 11 patients in good metabolic control group. Five patients had intellectual disability, 10 had EEG abnormalities, seven had abnormal VEP and two had abnormal BAEP results. MRI was abnormal in five patients. There was significant correlation between the number of hypoglycemic attacks and MRI abnormalities. Central nervous system may be affected in GSD type 1a even in patients with normal neurologic examination. Accumulation of abnormal results in patients with poor metabolic control supports the importance of metabolic control in GSD type 1a.

  18. Abnormal Uterine Bleeding: American College of Nurse-Midwives.

    PubMed

    2016-07-01

    Variations in uterine bleeding, termed abnormal uterine bleeding, occur commonly among women and often are physiologic in nature with no significant consequences. However, abnormal uterine bleeding can cause significant distress to women or may signify an underlying pathologic condition. Most women experience variations in menstrual and perimenstrual bleeding in their lifetimes; therefore, the ability of the midwife to differentiate between normal and abnormal bleeding is a key diagnostic skill. A comprehensive history and use of the PALM-COEIN classification system will provide clear guidelines for clinical management, evidence-based treatment, and an individualized plan of care. The purpose of this Clinical Bulletin is to define and describe classifications of abnormal uterine bleeding, review updated terminology, and identify methods of assessment and treatment using a woman-centered approach. © 2016 by the American College of Nurse-Midwives.

  19. Effects of visual and motion simulation cueing systems on pilot performance during takeoffs with engine failures

    NASA Technical Reports Server (NTRS)

    Parris, B. L.; Cook, A. M.

    1978-01-01

    Data are presented that show the effects of visual and motion during cueing on pilot performance during takeoffs with engine failures. Four groups of USAF pilots flew a simulated KC-135 using four different cueing systems. The most basic of these systems was of the instrument-only type. Visual scene simulation and/or motion simulation was added to produce the other systems. Learning curves, mean performance, and subjective data are examined. The results show that the addition of visual cueing results in significant improvement in pilot performance, but the combined use of visual and motion cueing results in far better performance.

  20. Analysis and Selection of a Remote Docking Simulation Visual Display System

    NASA Technical Reports Server (NTRS)

    Shields, N., Jr.; Fagg, M. F.

    1984-01-01

    The development of a remote docking simulation visual display system is examined. Video system and operator performance are discussed as well as operator command and control requirements and a design analysis of the reconfigurable work station.

  1. Electrocardiogram abnormalities and coronary calcification in postmenopausal women.

    PubMed

    Sabour, Siamak; Grobbee, Diederick; Rutten, Annemarieke; Prokop, Mathias; Bartelink, Marie-Louise; van der Schouw, Yvonne; Bots, Michiel

    2010-01-01

    An electrocardiogram (ECG) can provide information on subclinical myocardial damage. The presence, and more importantly, the quantity of coronary artery calcification (CAC), relates well with the overall severity of the atherosclerotic process. A strong relation has been demonstrated between coronary calcium burden and the incidence of myocardial infarction, a relation independent of age. The aim of this study was to assess the relation of left ventricular hypertrophy (LVH) and ECG abnormalities with CAC. The study population comprised 566 postmenopausal women selected from a population-based cohort study. Information on LVH and repolarization abnormalities (T-axis and QRS-T angle) was obtained using electrocardiography. Modular ECG Analysis System (MEANS) was used to assess ECG abnormalities. The women underwent a multi detector-row computed tomography (MDCT) scan (Philips Mx 8000 IDT 16) to assess CAC. The Agatston score was used to quantify CAC; scores greater than zero were considered as the presence of coronary calcium. Logistic regression was used to assess the relation of ECG abnormality with coronary calcification. LVH was found in 2.7% (n = 15) of the women. The prevalence of T-axis abnormality was 6% (n = 34), whereas 8.5% (n = 48) had a QRS-T angle abnormality. CAC was found in 62% of the women. Compared to women with a normal T-axis, women with borderline or abnormal T-axes were 3.8 fold more likely to have CAC (95% CI: 1.4-10.2). Similarly, compared to women with a normal QRS-T angle, in women with borderline or abnormal QRS-T angle, CAC was 2.0 fold more likely to be present (95% CI: 1.0-4.1). Among women with ECG abnormalities reflecting subclinical ischemia, CAC is commonly found and may in part explain the increased coronary heart disease risk associated with these ECG abnormalities.

  2. Electrocardiogram Abnormalities and Coronary Calcification in Postmenopausal Women

    PubMed Central

    Sabour, Siamak; Grobbee, Diederick; Rutten, Annemarieke; Prokop, Mathias; Bartelink, Marie-Louise; van der Schouw, Yvonne; Bots, Michiel

    2010-01-01

    Background: An electrocardiogram (ECG) can provide information on subclinical myocardial damage. The presence, and more importantly, the quantity of coronary artery calcification (CAC), relates well with the overall severity of the atherosclerotic process. A strong relation has been demonstrated between coronary calcium burden and the incidence of myocardial infarction, a relation independent of age. The aim of this study was to assess the relation of left ventricular hypertrophy (LVH) and ECG abnormalities with CAC. Methods: The study population comprised 566 postmenopausal women selected from a population-based cohort study. Information on LVH and repolarization abnormalities (T-axis and QRS-T angle) was obtained using electrocardiography. Modular ECG Analysis System (MEANS) was used to assess ECG abnormalities. The women underwent a multi detector-row computed tomography (MDCT) scan (Philips Mx 8000 IDT 16) to assess CAC. The Agatston score was used to quantify CAC; scores greater than zero were considered as the presence of coronary calcium. Logistic regression was used to assess the relation of ECG abnormality with coronary calcification. Results: LVH was found in 2.7% (n = 15) of the women. The prevalence of T-axis abnormality was 6% (n = 34), whereas 8.5% (n = 48) had a QRS-T angle abnormality. CAC was found in 62% of the women. Compared to women with a normal T-axis, women with borderline or abnormal T-axes were 3.8 fold more likely to have CAC (95% CI: 1.4–10.2). Similarly, compared to women with a normal QRS-T angle, in women with borderline or abnormal QRS-T angle, CAC was 2.0 fold more likely to be present (95% CI: 1.0–4.1). Conclusion: Among women with ECG abnormalities reflecting subclinical ischemia, CAC is commonly found and may in part explain the increased coronary heart disease risk associated with these ECG abnormalities. PMID:23074563

  3. Abnormal functional motor lateralization in healthy siblings of patients with schizophrenia.

    PubMed

    Altamura, Mario; Fazio, Leonardo; De Salvia, Michela; Petito, Annamaria; Blasi, Giuseppe; Taurisano, Paolo; Romano, Raffaella; Gelao, Barbara; Bellomo, Antonello; Bertolino, Alessandro

    2012-07-30

    Earlier neuroimaging studies of motor function in schizophrenia have demonstrated reduced functional lateralization in the motor network during motor tasks. Here, we used event-related functional magnetic resonance imaging during a visually guided motor task in 18 clinically unaffected siblings of patients with schizophrenia and 24 matched controls to investigate if abnormal functional lateralization is related to genetic risk for this brain disorder. Whereas activity associated with motor task performance was mainly contralateral with only a marginal ipsilateral component in healthy participants, unaffected siblings had strong bilateral activity with significantly greater response in ipsilateral and contralateral premotor areas as well as in contralateral subcortical motor regions relative to controls. Reduced lateralization in siblings was also identified with a measure of laterality quotient. These findings suggest that abnormal functional lateralization of motor circuitry is related to genetic risk of schizophrenia. Copyright © 2012 Elsevier Ireland Ltd. All rights reserved.

  4. A Web-based Visualization System for Three Dimensional Geological Model using Open GIS

    NASA Astrophysics Data System (ADS)

    Nemoto, T.; Masumoto, S.; Nonogaki, S.

    2017-12-01

    A three dimensional geological model is an important information in various fields such as environmental assessment, urban planning, resource development, waste management and disaster mitigation. In this study, we have developed a web-based visualization system for 3D geological model using free and open source software. The system has been successfully implemented by integrating web mapping engine MapServer and geographic information system GRASS. MapServer plays a role of mapping horizontal cross sections of 3D geological model and a topographic map. GRASS provides the core components for management, analysis and image processing of the geological model. Online access to GRASS functions has been enabled using PyWPS that is an implementation of WPS (Web Processing Service) Open Geospatial Consortium (OGC) standard. The system has two main functions. Two dimensional visualization function allows users to generate horizontal and vertical cross sections of 3D geological model. These images are delivered via WMS (Web Map Service) and WPS OGC standards. Horizontal cross sections are overlaid on the topographic map. A vertical cross section is generated by clicking a start point and an end point on the map. Three dimensional visualization function allows users to visualize geological boundary surfaces and a panel diagram. The user can visualize them from various angles by mouse operation. WebGL is utilized for 3D visualization. WebGL is a web technology that brings hardware-accelerated 3D graphics to the browser without installing additional software. The geological boundary surfaces can be downloaded to incorporate the geologic structure in a design on CAD and model for various simulations. This study was supported by JSPS KAKENHI Grant Number JP16K00158.

  5. Abnormal Uterine Bleeding FAQ

    MedlinePlus

    ... Abnormal Uterine Bleeding • What is a normal menstrual cycle? • When is bleeding abnormal? • At what ages is ... abnormal bleeding? •Glossary What is a normal menstrual cycle? The normal length of the menstrual cycle is ...

  6. Altered transfer of visual motion information to parietal association cortex in untreated first-episode psychosis: Implications for pursuit eye tracking

    PubMed Central

    Lencer, Rebekka; Keedy, Sarah K.; Reilly, James L.; McDonough, Bruce E.; Harris, Margret S. H.; Sprenger, Andreas; Sweeney, John A.

    2011-01-01

    Visual motion processing and its use for pursuit eye movement control represent a valuable model for studying the use of sensory input for action planning. In psychotic disorders, alterations of visual motion perception have been suggested to cause pursuit eye tracking deficits. We evaluated this system in functional neuroimaging studies of untreated first-episode schizophrenia (N=24), psychotic bipolar disorder patients (N=13) and healthy controls (N=20). During a passive visual motion processing task, both patient groups showed reduced activation in the posterior parietal projection fields of motion-sensitive extrastriate area V5, but not in V5 itself. This suggests reduced bottom-up transfer of visual motion information from extrastriate cortex to perceptual systems in parietal association cortex. During active pursuit, activation was enhanced in anterior intraparietal sulcus and insula in both patient groups, and in dorsolateral prefrontal cortex and dorsomedial thalamus in schizophrenia patients. This may result from increased demands on sensorimotor systems for pursuit control due to the limited availability of perceptual motion information about target speed and tracking error. Visual motion information transfer deficits to higher -level association cortex may contribute to well-established pursuit tracking abnormalities, and perhaps to a wider array of alterations in perception and action planning in psychotic disorders. PMID:21873035

  7. A Low-Cost Audio Prescription Labeling System Using RFID for Thai Visually-Impaired People.

    PubMed

    Lertwiriyaprapa, Titipong; Fakkheow, Pirapong

    2015-01-01

    This research aims to develop a low-cost audio prescription labeling (APL) system for visually-impaired people by using the RFID system. The developed APL system includes the APL machine and APL software. The APL machine is for visually-impaired people while APL software allows caregivers to record all important information into the APL machine. The main objective of the development of the APL machine is to reduce costs and size by designing all of the electronic devices to fit into one print circuit board. Also, it is designed so that it is easy to use and can become an electronic aid for daily living. The developed APL software is based on Java and MySQL, both of which can operate on various operating platforms and are easy to develop as commercial software. The developed APL system was first evaluated by 5 experts. The APL system was also evaluated by 50 actual visually-impaired people (30 elders and 20 blind individuals) and 20 caregivers, pharmacists and nurses. After using the APL system, evaluations were carried out, and it can be concluded from the evaluation results that this proposed APL system can be effectively used for helping visually-impaired people in terms of self-medication.

  8. Visualization techniques for tongue analysis in traditional Chinese medicine

    NASA Astrophysics Data System (ADS)

    Pham, Binh L.; Cai, Yang

    2004-05-01

    Visual inspection of the tongue has been an important diagnostic method of Traditional Chinese Medicine (TCM). Clinic data have shown significant connections between various viscera cancers and abnormalities in the tongue and the tongue coating. Visual inspection of the tongue is simple and inexpensive, but the current practice in TCM is mainly experience-based and the quality of the visual inspection varies between individuals. The computerized inspection method provides quantitative models to evaluate color, texture and surface features on the tongue. In this paper, we investigate visualization techniques and processes to allow interactive data analysis with the aim to merge computerized measurements with human expert's diagnostic variables based on five-scale diagnostic conditions: Healthy (H), History Cancers (HC), History of Polyps (HP), Polyps (P) and Colon Cancer (C).

  9. Real-time unconstrained object recognition: a processing pipeline based on the mammalian visual system.

    PubMed

    Aguilar, Mario; Peot, Mark A; Zhou, Jiangying; Simons, Stephen; Liao, Yuwei; Metwalli, Nader; Anderson, Mark B

    2012-03-01

    The mammalian visual system is still the gold standard for recognition accuracy, flexibility, efficiency, and speed. Ongoing advances in our understanding of function and mechanisms in the visual system can now be leveraged to pursue the design of computer vision architectures that will revolutionize the state of the art in computer vision.

  10. Abnormal tuning of saccade-related cells in pontine reticular formation of strabismic monkeys.

    PubMed

    Walton, Mark M G; Mustari, Michael J

    2015-08-01

    Strabismus is a common disorder, characterized by a chronic misalignment of the eyes and numerous visual and oculomotor abnormalities. For example, saccades are often highly disconjugate. For humans with pattern strabismus, the horizontal and vertical disconjugacies vary with eye position. In monkeys, manipulations that disturb binocular vision during the first several weeks of life result in a chronic strabismus with characteristics that closely match those in human patients. Early onset strabismus is associated with altered binocular sensitivity of neurons in visual cortex. Here we test the hypothesis that brain stem circuits specific to saccadic eye movements are abnormal. We targeted the pontine paramedian reticular formation, a structure that directly projects to the ipsilateral abducens nucleus. In normal animals, neurons in this structure are characterized by a high-frequency burst of spikes associated with ipsiversive saccades. We recorded single-unit activity from 84 neurons from four monkeys (two normal, one exotrope, and one esotrope), while they made saccades to a visual target on a tangent screen. All 24 neurons recorded from the normal animals had preferred directions within 30° of pure horizontal. For the strabismic animals, the distribution of preferred directions was normal on one side of the brain, but highly variable on the other. In fact, 12/60 neurons recorded from the strabismic animals preferred vertical saccades. Many also had unusually weak or strong bursts. These data suggest that the loss of corresponding binocular vision during infancy impairs the development of normal tuning characteristics for saccade-related neurons in brain stem. Copyright © 2015 the American Physiological Society.

  11. Effect of abnormal notochord delamination on hindgut development in the Adriamycin mouse model.

    PubMed

    Sato, Hideaki; Hajduk, Piotr; Furuta, Shigeyuki; Wakisaka, Munechika; Murphy, Paula; Puri, Prem; Kitagawa, Hiroaki

    2013-11-01

    Adriamycin mouse model (AMM) is a model of VACTERL anomalies. Sonic hedgehog (Shh) pathway, sourced by the notochord, is implicated of anorectal malformations. We hypothesized hindgut anomalies observed in the AMM are the result of abnormal effect of the notochord. Time-mated CBA/Ca mice received two intraperitoneal injections of Adriamycin (6 mg/kg) or saline as control on embryonic day (E) 7 and 8. Fetuses were harvested from E9 to E11, stained following whole mount in situ hybridization with labeled RNA probes to detect Shh and Fork head box F1(Foxf1) transcripts. Immunolocalization with endoderm marker Hnf3β was used to visualize morphology. Embryos were scanned by OPT to obtain 3D representations of expressions. In AMM, the notochord was abnormally displaced ventrally with attachment to the hindgut endoderm in 71 % of the specimens. In 32 % of the treated embryos abnormal hindgut ended blindly in a cystic structure, and both of types were remarked in 29 % of treated embryos. Endodermal Shh and mesenchymal Foxf1 genes expression were preserved around the hindgut cystic malformation. The delamination of the developing notochord in the AMM is disrupted, which may influence signaling mechanisms from the notochord to the hindgut resulting in abnormal patterning of the hindgut.

  12. Issues in visual support to real-time space system simulation solved in the Systems Engineering Simulator

    NASA Technical Reports Server (NTRS)

    Yuen, Vincent K.

    1989-01-01

    The Systems Engineering Simulator has addressed the major issues in providing visual data to its real-time man-in-the-loop simulations. Out-the-window views and CCTV views are provided by three scene systems to give the astronauts their real-world views. To expand the window coverage for the Space Station Freedom workstation a rotating optics system is used to provide the widest field of view possible. To provide video signals to as many viewpoints as possible, windows and CCTVs, with a limited amount of hardware, a video distribution system has been developed to time-share the video channels among viewpoints at the selection of the simulation users. These solutions have provided the visual simulation facility for real-time man-in-the-loop simulations for the NASA space program.

  13. FGF /FGFR Signal Induces Trachea Extension in the Drosophila Visual System

    PubMed Central

    Chu, Wei-Chen; Lee, Yuan-Ming; Henry Sun, Yi

    2013-01-01

    The Drosophila compound eye is a large sensory organ that places a high demand on oxygen supplied by the tracheal system. Although the development and function of the Drosophila visual system has been extensively studied, the development and contribution of its tracheal system has not been systematically examined. To address this issue, we studied the tracheal patterns and developmental process in the Drosophila visual system. We found that the retinal tracheae are derived from air sacs in the head, and the ingrowth of retinal trachea begin at mid-pupal stage. The tracheal development has three stages. First, the air sacs form near the optic lobe in 42-47% of pupal development (pd). Second, in 47-52% pd, air sacs extend branches along the base of the retina following a posterior-to-anterior direction and further form the tracheal network under the fenestrated membrane (TNUFM). Third, the TNUFM extend fine branches into the retina following a proximal-to-distal direction after 60% pd. Furthermore, we found that the trachea extension in both retina and TNUFM are dependent on the FGF(Bnl)/FGFR(Btl) signaling. Our results also provided strong evidence that the photoreceptors are the source of the Bnl ligand to guide the trachea ingrowth. Our work is the first systematic study of the tracheal development in the visual system, and also the first study demonstrating the interactions of two well-studied systems: the eye and trachea. PMID:23991208

  14. Impulse processing: A dynamical systems model of incremental eye movements in the visual world paradigm

    PubMed Central

    Kukona, Anuenue; Tabor, Whitney

    2011-01-01

    The visual world paradigm presents listeners with a challenging problem: they must integrate two disparate signals, the spoken language and the visual context, in support of action (e.g., complex movements of the eyes across a scene). We present Impulse Processing, a dynamical systems approach to incremental eye movements in the visual world that suggests a framework for integrating language, vision, and action generally. Our approach assumes that impulses driven by the language and the visual context impinge minutely on a dynamical landscape of attractors corresponding to the potential eye-movement behaviors of the system. We test three unique predictions of our approach in an empirical study in the visual world paradigm, and describe an implementation in an artificial neural network. We discuss the Impulse Processing framework in relation to other models of the visual world paradigm. PMID:21609355

  15. Temporal lobe developmental malformations and epilepsy: dual pathology and bilateral hippocampal abnormalities.

    PubMed

    Ho, S S; Kuzniecky, R I; Gilliam, F; Faught, E; Morawetz, R

    1998-03-01

    Temporal lobe developmental malformations (TLDM) with focal cortical dysplasia and balloon cells may coexist with mesial temporal sclerosis. The true incidence of this dual pathology is unknown. Our aim was to assess the frequency of amygdala (AM)-hippocampal abnormality in a homogeneous population with this specific developmental malformation. MRI-based volumetry of the AM and hippocampal formation (HF) in 30 patients with unilateral TLDM and intractable partial epilepsy was performed. A volume normalization process defined a normal range of HF and AM volumes in control subjects, and enabled the detection of bilateral volume loss. Normalized volumes detected HF atrophy in 26 patients (nine unilateral and 17 bilateral) and AM atrophy in 18 patients (three unilateral and 15 bilateral). Visual analysis detected unilateral HF abnormality in 21 patients and bilateral abnormality in two. When compared with a group of patients with temporal lobe epilepsy and pure hippocampal sclerosis (N = 92), where volumetry revealed bilateral HF atrophy in 18%, a significant difference in the frequency of bilateral HF atrophy was found (p < 0.0001). Dual pathology is frequent in patients with TLDM (87%), and the AM-HF abnormality is often bilateral (57%). Our data suggest that more widespread and potentially epileptogenic lesions coexist with visibly detectable unilateral TLDM. This has implications for the selection of patients for temporal lobe surgery and may influence surgical strategies.

  16. Visual outcomes in children in Malawi following retinopathy of severe malaria

    PubMed Central

    Beare, N A V; Southern, C; Kayira, K; Taylor, T E; Harding, S P

    2004-01-01

    Aim: To investigate whether retinal changes in children with severe malaria affect visual acuity 1 month after systemic recovery. Methods: All children with severe malaria admitted to a research ward in Malawi during one malaria season were examined by direct and indirect ophthalmoscopy. Visual acuity was tested in those attending follow up by Cardiff cards, Sheridan-Gardiner single letters, or Snellen chart. Results: 96 (68%) children attended follow up, of whom 83 (86%) had visual acuity measured. Cardiff cards were used in 47 (57%) children, and Sheridan-Gardiner letters or Snellen chart in 29 (35%). There was no significant difference in the mean logMAR visual acuity between groups with or without macular whitening (0.14 versus 0.16, p = 0.55). There was no trend for worse visual acuity with increasing severity of macular whitening (p = 0.52) including patients in whom the fovea was involved (p = 0.32). Six (4.2%) children had cortical blindness after cerebral malaria, and all six had other neurological sequelae. Ophthalmoscopy during the acute illness revealed no abnormalities in four of these children. Conclusion: Retinal changes in severe malaria, in particular macular whitening, do not appear to affect visual acuity at 1 month. This supports the hypothesis that retinal whitening is due to reversible intracellular oedema in response to relative hypoxia, caused by sequestered erythrocytes infected by Plasmodium falciparum. Impaired visual functioning after cerebral malaria is not attributable to retinal changes and appears to be a cortical phenomenon. PMID:14977760

  17. Urine - abnormal color

    MedlinePlus

    ... medlineplus.gov/ency/article/003139.htm Urine - abnormal color To use the sharing features on this page, please enable JavaScript. The usual color of urine is straw-yellow. Abnormally colored urine ...

  18. JackIn Head: Immersive Visual Telepresence System with Omnidirectional Wearable Camera.

    PubMed

    Kasahara, Shunichi; Nagai, Shohei; Rekimoto, Jun

    2017-03-01

    Sharing one's own immersive experience over the Internet is one of the ultimate goals of telepresence technology. In this paper, we present JackIn Head, a visual telepresence system featuring an omnidirectional wearable camera with image motion stabilization. Spherical omnidirectional video footage taken around the head of a local user is stabilized and then broadcast to others, allowing remote users to explore the immersive visual environment independently of the local user's head direction. We describe the system design of JackIn Head and report the evaluation results of real-time image stabilization and alleviation of cybersickness. Then, through an exploratory observation study, we investigate how individuals can remotely interact, communicate with, and assist each other with our system. We report our observation and analysis of inter-personal communication, demonstrating the effectiveness of our system in augmenting remote collaboration.

  19. Visualizing request-flow comparison to aid performance diagnosis in distributed systems.

    PubMed

    Sambasivan, Raja R; Shafer, Ilari; Mazurek, Michelle L; Ganger, Gregory R

    2013-12-01

    Distributed systems are complex to develop and administer, and performance problem diagnosis is particularly challenging. When performance degrades, the problem might be in any of the system's many components or could be a result of poor interactions among them. Recent research efforts have created tools that automatically localize the problem to a small number of potential culprits, but research is needed to understand what visualization techniques work best for helping distributed systems developers understand and explore their results. This paper compares the relative merits of three well-known visualization approaches (side-by-side, diff, and animation) in the context of presenting the results of one proven automated localization technique called request-flow comparison. Via a 26-person user study, which included real distributed systems developers, we identify the unique benefits that each approach provides for different problem types and usage modes.

  20. Subjective visual vertical assessment with mobile virtual reality system.

    PubMed

    Ulozienė, Ingrida; Totilienė, Milda; Paulauskas, Andrius; Blažauskas, Tomas; Marozas, Vaidotas; Kaski, Diego; Ulozas, Virgilijus

    2017-01-01

    The subjective visual vertical (SVV) is a measure of a subject's perceived verticality, and a sensitive test of vestibular dysfunction. Despite this, and consequent upon technical and logistical limitations, SVV has not entered mainstream clinical practice. The aim of the study was to develop a mobile virtual reality based system for SVV test, evaluate the suitability of different controllers and assess the system's usability in practical settings. In this study, we describe a novel virtual reality based system that has been developed to test SVV using integrated software and hardware, and report normative values across healthy population. Participants wore a mobile virtual reality headset in order to observe a 3D stimulus presented across separate conditions - static, dynamic and an immersive real-world ("boat in the sea") SVV tests. The virtual reality environment was controlled by the tester using a Bluetooth connected controllers. Participants controlled the movement of a vertical arrow using either a gesture control armband or a general-purpose gamepad, to indicate perceived verticality. We wanted to compare 2 different methods for object control in the system, determine normal values and compare them with literature data, to evaluate the developed system with the help of the system usability scale questionnaire and evaluate possible virtually induced dizziness with the help of subjective visual analog scale. There were no statistically significant differences in SVV values during static, dynamic and virtual reality stimulus conditions, obtained using the two different controllers and the results are compared to those previously reported in the literature using alternative methodologies. The SUS scores for the system were high, with a median of 82.5 for the Myo controller and of 95.0 for the Gamepad controller, representing a statistically significant difference between the two controllers (P<0.01). The median of virtual reality-induced dizziness for both

  1. Increasing cyanosis early after cavopulmonary connection caused by abnormal systemic venous channels.

    PubMed

    Gatzoulis, M A; Shinebourne, E A; Redington, A N; Rigby, M L; Ho, S Y; Shore, D F

    1995-02-01

    To show that abnormal systemic venous channels in patients who undergo cavopulmonary anastomoses can become manifest and haemodynamically important only after surgery despite detailed preoperative investigation. Descriptive study of patients fulfilling the above criteria selected from hospital records over the past three years. A tertiary referral centre. Of the three cases identified, two were isomeric, one with left atrial isomerism and hemiazygos continuation of the inferior vena cava who underwent bilateral bidirectional Glenn anastomoses and one with right isomerism who underwent total cavopulmonary anastomosis. Case 3 had absent left atrioventricular connection with a hypoplastic left lung and underwent a classic right Glenn procedure. All three cases presented with progressive cyanosis in the early postoperative period. Postoperative angiography in case 1 showed a remnant of a left inferior vena cava draining to the atrium to have become grossly dilated causing cyanosis, which resolved after redirection of this vessel and of the hepatic veins into the right pulmonary artery with an intra-atrial baffle. Cyanosis in case 2 was caused by intra-hepatic shunting to a hepatic vein draining to the left of the intra-atrial baffle. The diagnosis was made at necropsy, being overlooked on postoperative angiography. Repeat angiography in case 3 showed progressive dilatation of a small left superior vena cava to coronary sinus. Test occlusion with a view to embolisation revealed hitherto an undemonstrated hemiazygos continuation of inferior caval to brachiocephalic vein. The patient underwent surgical ligation of these two venous channels. Despite appropriate investigation some "abnormal" venous pathways manifest themselves, dilate, and become haemodynamically important only after surgical cavopulmonary anastomoses. In the presence of early postoperative cyanosis "new" systemic venous collateral channels should be considered as a possible cause, which may require

  2. a Three-Dimensional Simulation and Visualization System for Uav Photogrammetry

    NASA Astrophysics Data System (ADS)

    Liang, Y.; Qu, Y.; Cui, T.

    2017-08-01

    Nowadays UAVs has been widely used for large-scale surveying and mapping. Compared with manned aircraft, UAVs are more cost-effective and responsive. However, UAVs are usually more sensitive to wind condition, which greatly influences their positions and orientations. The flight height of a UAV is relative low, and the relief of the terrain may result in serious occlusions. Moreover, the observations acquired by the Position and Orientation System (POS) are usually less accurate than those acquired in manned aerial photogrammetry. All of these factors bring in uncertainties to UAV photogrammetry. To investigate these uncertainties, a three-dimensional simulation and visualization system has been developed. The system is demonstrated with flight plan evaluation, image matching, POS-supported direct georeferencing, and ortho-mosaicing. Experimental results show that the presented system is effective for flight plan evaluation. The generated image pairs are accurate and false matches can be effectively filtered. The presented system dynamically visualizes the results of direct georeferencing in three-dimensions, which is informative and effective for real-time target tracking and positioning. The dynamically generated orthomosaic can be used in emergency applications. The presented system has also been used for teaching theories and applications of UAV photogrammetry.

  3. Compensation for time delay in flight simulator visual-display systems

    NASA Technical Reports Server (NTRS)

    Crane, D. F.

    1983-01-01

    A piloted aircraft can be viewed as a closed-loop, man-machine control system. When a simulator pilot is performing a precision maneuver, a delay in the visual display of aircraft response to pilot-control input decreases the stability of the pilot-aircraft system. The less stable system is more difficult to control precisely. Pilot dynamic response and performance change as the pilot attempts to compensate for the decrease in system stability, and these changes bias the simulation results by influencing the pilot's rating of the handling qualities of the simulated aircraft. Delay compensation, designed to restore pilot-aircraft system stability, was evaluated in several studies which are reported here. The studies range from single-axis, tracking-task experiments (with sufficient subjects and trials to establish statistical significance of the results) to a brief evaluation of compensation of a computer-generated-imagery (CGI) visual display system in a full six-degree-of-freedom simulation. The compensation was effective - improvements in pilot performance and workload or aircraft handling-qualities rating (HQR) were observed. Results from recent aircraft handling-qualities research literature which support the compensation design approach are also reviewed.

  4. Automated visual inspection system based on HAVNET architecture

    NASA Astrophysics Data System (ADS)

    Burkett, K.; Ozbayoglu, Murat A.; Dagli, Cihan H.

    1994-10-01

    In this study, the HAusdorff-Voronoi NETwork (HAVNET) developed at the UMR Smart Engineering Systems Lab is tested in the recognition of mounted circuit components commonly used in printed circuit board assembly systems. The automated visual inspection system used consists of a CCD camera, a neural network based image processing software and a data acquisition card connected to a PC. The experiments are run in the Smart Engineering Systems Lab in the Engineering Management Dept. of the University of Missouri-Rolla. The performance analysis shows that the vision system is capable of recognizing different components under uncontrolled lighting conditions without being effected by rotation or scale differences. The results obtained are promising and the system can be used in real manufacturing environments. Currently the system is being customized for a specific manufacturing application.

  5. Functional vision and cognition in infants with congenital disorders of the peripheral visual system.

    PubMed

    Dale, Naomi; Sakkalou, Elena; O'Reilly, Michelle; Springall, Clare; De Haan, Michelle; Salt, Alison

    2017-07-01

    To investigate how vision relates to early development by studying vision and cognition in a national cohort of 1-year-old infants with congenital disorders of the peripheral visual system and visual impairment. This was a cross-sectional observational investigation of a nationally recruited cohort of infants with 'simple' and 'complex' congenital disorders of the peripheral visual system. Entry age was 8 to 16 months. Vision level (Near Detection Scale) and non-verbal cognition (sensorimotor understanding, Reynell Zinkin Scales) were assessed. Parents completed demographic questionnaires. Of 90 infants (49 males, 41 females; mean 13mo, standard deviation [SD] 2.5mo; range 7-17mo); 25 (28%) had profound visual impairment (light perception at best) and 65 (72%) had severe visual impairment (basic 'form' vision). The Near Detection Scale correlated significantly with sensorimotor understanding developmental quotients in the 'total', 'simple', and 'complex' groups (all p<0.001). Age and vision accounted for 48% of sensorimotor understanding variance. Infants with profound visual impairment, especially in the 'complex' group with congenital disorders of the peripheral visual system with known brain involvement, showed the greatest cognitive delay. Lack of vision is associated with delayed early-object manipulative abilities and concepts; 'form' vision appeared to support early developmental advance. This paper provides baseline characteristics for cross-sectional and longitudinal follow-up investigations in progress. A methodological strength of the study was the representativeness of the cohort according to national epidemiological and population census data. © 2017 Mac Keith Press.

  6. Scanning laser polarimetry, but not optical coherence tomography predicts permanent visual field loss in acute nonarteritic anterior ischemic optic neuropathy.

    PubMed

    Kupersmith, Mark J; Anderson, Susan; Durbin, Mary; Kardon, Randy

    2013-08-15

    Scanning laser polarimetry (SLP) reveals abnormal retardance of birefringence in locations of the edematous peripapillary retinal nerve fiber layer (RNFL), which appear thickened by optical coherence tomography (OCT), in nonarteritic anterior ischemic optic neuropathy (NAION). We hypothesize initial sector SLP RNFL abnormalities will correlate with long-term regional visual field loss due to ischemic injury. We prospectively performed automated perimetry, SLP, and high definition OCT (HD-OCT) of the RNFL in 25 eyes with acute NAION. We grouped visual field threshold and RNFL values into Garway-Heath inferior/superior disc sectors and corresponding superior/inferior field regions. We compared sector SLP RNFL thickness with corresponding visual field values at presentation and at >3 months. At presentation, 12 eyes had superior sector SLP reduction, 11 of which had inferior field loss. Six eyes, all with superior field loss, had inferior sector SLP reduction. No eyes had reduced OCT-derived RNFL acutely. Eyes with abnormal field regions had corresponding SLP sectors thinner (P = 0.003) than for sectors with normal field regions. During the acute phase, the SLP-derived sector correlated with presentation (r = 0.59, P = 0.02) and with >3-month after presentation (r = 0.44, P = 0.02) corresponding superior and inferior field thresholds. Abnormal RNFL birefringence occurs in sectors corresponding to regional visual field loss during acute NAION when OCT-derived RNFL shows thickening. Since the visual field deficits show no significant recovery, SLP can be an early marker for axonal injury, which may be used to assess recovery potential at RNFL locations with respect to new treatments for acute NAION.

  7. SAVS: A Space and Atmospheric Visualization Science system

    NASA Technical Reports Server (NTRS)

    Szuszczewicz, E. P.; Mankofsky, A.; Blanchard, P.; Goodrich, C.; McNabb, D.; Kamins, D.

    1995-01-01

    The research environment faced by space and atmospheric scientists in the 1990s is characterized by unprecedented volumes of new data, by ever-increasing repositories of unexploited mission files, and by the widespread use of empirical and large-scale computational models needed for the synthesis of understanding across data sets and discipline boundaries. The effective analysis and interpretation of such massive amounts of information have become the subjects of legitimate concern. With SAVS (a Space and Atmospheric Visualization Science System), we address these issues by creating a 'push-button' software environment that mimics the logical scientific processes in data acquisition, reduction, and analysis without requiring a detailed understanding of the methods, networks, and modules that link the tools and effectively execute the functions. SAVS provides (1) a customizable framework for accessing a powerful set of visualization tools based on the popular AVS visualization software with hooks to PV-Wave and access to Khoros modules, (2) a set of mathematical and statistical tools, (3) an extensible library of discipline-specific functions and models (e.g., MSIS, IRI, Feldstein Oval, IGRF, satellite tracking with CADRE-3, etc.), and (4) capabilities for local and remote data base access. The system treats scalar, vector, and image data, and runs on most common Unix workstations. We present a description of SAVS and its components, followed by several applications based on generic research interests in interplanetary and magnetospheric physics (IMP/ISTP), active experiments in space (CRRES), and mission planning focused on the Earth's thermospheric, ionospheric, and mesospheric domains (TIMED).

  8. Abnormal sleep/wake dynamics in orexin knockout mice.

    PubMed

    Diniz Behn, Cecilia G; Klerman, Elizabeth B; Mochizuki, Takatoshi; Lin, Shih-Chieh; Scammell, Thomas E

    2010-03-01

    Narcolepsy with cataplexy is caused by a loss of orexin (hypocretin) signaling, but the physiologic mechanisms that result in poor maintenance of wakefulness and fragmented sleep remain unknown. Conventional scoring of sleep cannot reveal much about the process of transitioning between states or the variations within states. We developed an EEG spectral analysis technique to determine whether the state instability in a mouse model of narcolepsy reflects abnormal sleep or wake states, faster movements between states, or abnormal transitions between states. We analyzed sleep recordings in orexin knockout (OXKO) mice and wild type (WT) littermates using a state space analysis technique. This non-categorical approach allows quantitative and unbiased examination of sleep/wake states and state transitions. OXKO mice spent less time in deep, delta-rich NREM sleep and in active, theta-rich wake and instead spent more time near the transition zones between states. In addition, while in the midst of what should be stable wake, OXKO mice initiated rapid changes into NREM sleep with high velocities normally seen only in transition regions. Consequently, state transitions were much more frequent and rapid even though the EEG progressions during state transitions were normal. State space analysis enables visualization of the boundaries between sleep and wake and shows that narcoleptic mice have less distinct and more labile states of sleep and wakefulness. These observations provide new perspectives on the abnormal state dynamics resulting from disrupted orexin signaling and highlight the usefulness of state space analysis in understanding narcolepsy and other sleep disorders.

  9. CasCADe: A Novel 4D Visualization System for Virtual Construction Planning.

    PubMed

    Ivson, Paulo; Nascimento, Daniel; Celes, Waldemar; Barbosa, Simone Dj

    2018-01-01

    Building Information Modeling (BIM) provides an integrated 3D environment to manage large-scale engineering projects. The Architecture, Engineering and Construction (AEC) industry explores 4D visualizations over these datasets for virtual construction planning. However, existing solutions lack adequate visual mechanisms to inspect the underlying schedule and make inconsistencies readily apparent. The goal of this paper is to apply best practices of information visualization to improve 4D analysis of construction plans. We first present a review of previous work that identifies common use cases and limitations. We then consulted with AEC professionals to specify the main design requirements for such applications. These guided the development of CasCADe, a novel 4D visualization system where task sequencing and spatio-temporal simultaneity are immediately apparent. This unique framework enables the combination of diverse analytical features to create an information-rich analysis environment. We also describe how engineering collaborators used CasCADe to review the real-world construction plans of an Oil & Gas process plant. The system made evident schedule uncertainties, identified work-space conflicts and helped analyze other constructability issues. The results and contributions of this paper suggest new avenues for future research in information visualization for the AEC industry.

  10. Visual development in primates: Neural mechanisms and critical periods

    PubMed Central

    Kiorpes, Lynne

    2015-01-01

    Despite many decades of research into the development of visual cortex, it remains unclear what neural processes set limitations on the development of visual function and define its vulnerability to abnormal visual experience. This selected review examines the development of visual function and its neural correlates, and highlights the fact that in most cases receptive field properties of infant neurons are substantially more mature than infant visual function. One exception is temporal resolution, which can be accounted for by resolution of neurons at the level of the LGN. In terms of spatial vision, properties of single neurons alone are not sufficient to account for visual development. Different visual functions develop over different time courses. Their onset may be limited by the existence of neural response properties that support a given perceptual ability, but the subsequent time course of maturation to adult levels remains unexplained. Several examples are offered suggesting that taking account of weak signaling by infant neurons, correlated firing, and pooled responses of populations of neurons brings us closer to an understanding of the relationship between neural and behavioral development. PMID:25649764

  11. Effects of abnormal light-rearing conditions on retinal physiology in larvae zebrafish.

    PubMed

    Saszik, S; Bilotta, J

    1999-11-01

    Anatomic studies have found that zebrafish retinal neurons develop in a sequential fashion. In addition, exposure to abnormal light-rearing conditions produces deficits in visual behavior of larvae zebrafish, even though there appears to be little effect of the light-rearing conditions on the gross morphology of the retina. The purpose of this study was to assess the effects of abnormal light-rearing conditions on larvae zebrafish retinal physiology. Larvae zebrafish (Danio rerio) were exposed to constant light (LL), constant dark (DD), or normal cyclic light (LD) from fertilization to 6 days postfertilization (dpf). After 6 days, the animals were placed into normal cyclic light and tested at 6 to 8, 13 to 15, and 21 to 24 dpf. Electroretinogram (ERG) responses to visual stimuli, consisting of various wavelengths and irradiances, were recorded. Comparisons were made across the three age groups and the three light-rearing conditions. Deficits from the light-rearing conditions were seen immediately after exposure (6 8 dpf). The LL-condition subjects showed the greatest deficit in the UV and short-wavelength areas and the DD-condition subjects showed a slight deficit across the entire spectrum. At 13 to 15 dpf, the LL and DD groups showed an increase in sensitivity and by 21 to 24 dpf, the groups no longer differed from controls. Abnormal lighting environments can adversely influence the physiological development of the larvae zebrafish retina. The pattern of damage that was seen in zebrafish is similar to that found in other vertebrates, including higher vertebrates. However, unlike higher vertebrates, the zebrafish appears to be capable of regeneration. This suggests that the zebrafish would be a viable model for light environment effects and neural regeneration.

  12. Visual Hybrid Development Learning System (VHDLS) framework for children with autism.

    PubMed

    Banire, Bilikis; Jomhari, Nazean; Ahmad, Rodina

    2015-10-01

    The effect of education on children with autism serves as a relative cure for their deficits. As a result of this, they require special techniques to gain their attention and interest in learning as compared to typical children. Several studies have shown that these children are visual learners. In this study, we proposed a Visual Hybrid Development Learning System (VHDLS) framework that is based on an instructional design model, multimedia cognitive learning theory, and learning style in order to guide software developers in developing learning systems for children with autism. The results from this study showed that the attention of children with autism increased more with the proposed VHDLS framework.

  13. A reflective lens: applying critical systems thinking and visual methods to ecohealth research.

    PubMed

    Cleland, Deborah; Wyborn, Carina

    2010-12-01

    Critical systems methodology has been advocated as an effective and ethical way to engage with the uncertainty and conflicting values common to ecohealth problems. We use two contrasting case studies, coral reef management in the Philippines and national park management in Australia, to illustrate the value of critical systems approaches in exploring how people respond to environmental threats to their physical and spiritual well-being. In both cases, we used visual methods--participatory modeling and rich picturing, respectively. The critical systems methodology, with its emphasis on reflection, guided an appraisal of the research process. A discussion of these two case studies suggests that visual methods can be usefully applied within a critical systems framework to offer new insights into ecohealth issues across a diverse range of socio-political contexts. With this article, we hope to open up a conversation with other practitioners to expand the use of visual methods in integrated research.

  14. CAFE: an R package for the detection of gross chromosomal abnormalities from gene expression microarray data.

    PubMed

    Bollen, Sander; Leddin, Mathias; Andrade-Navarro, Miguel A; Mah, Nancy

    2014-05-15

    The current methods available to detect chromosomal abnormalities from DNA microarray expression data are cumbersome and inflexible. CAFE has been developed to alleviate these issues. It is implemented as an R package that analyzes Affymetrix *.CEL files and comes with flexible plotting functions, easing visualization of chromosomal abnormalities. CAFE is available from https://bitbucket.org/cob87icW6z/cafe/ as both source and compiled packages for Linux and Windows. It is released under the GPL version 3 license. CAFE will also be freely available from Bioconductor. sander.h.bollen@gmail.com or nancy.mah@mdc-berlin.de Supplementary data are available at Bioinformatics online.

  15. Preattentive visual search and perceptual grouping in schizophrenia.

    PubMed

    Carr, V J; Dewis, S A; Lewin, T J

    1998-06-15

    To help determine whether patients with schizophrenia show deficits in the stimulus-based aspects of preattentive processing, we undertook a series of experiments within the framework of feature integration theory. Thirty subjects with a DSM-III-R diagnosis of schizophrenia and 30 age-, gender-, and education-matched normal control subjects completed two computerized experimental tasks, a visual search task assessing parallel and serial information processing (Experiment 1) and a task which examined the effects of perceptual grouping on visual search strategies (Experiment 2). We also assessed current symptomatology and its relationship to task performance. While the schizophrenia subjects had longer reaction times in Experiment 1, their overall pattern of performance across both experimental tasks was similar to that of the control subjects, and generally unrelated to current symptomatology. Predictions from feature integration theory about the impact of varying display size (Experiment 1) and number of perceptual groups (Experiment 2) on the detection of feature and conjunction targets were strongly supported. This study revealed no firm evidence that schizophrenia is associated with a preattentive abnormality in visual search using stimuli that differ on the basis of physical characteristics. While subject and task characteristics may partially account for differences between this and previous studies, it is more likely that preattentive processing abnormalities in schizophrenia may occur only under conditions involving selected 'top-down' factors such as context and meaning.

  16. Expert opinion on best practice guidelines and competency framework for visual screening in children.

    PubMed

    Lança, Carla

    2013-09-01

    Screening programs to detect visual abnormalities in children vary among countries. The aim of this study is to describe experts' perception of best practice guidelines and competency framework for visual screening in children. A qualitative focus group technique was applied during the Portuguese national orthoptic congress to obtain the perception of an expert panel of 5 orthoptists and 2 ophthalmologists with experience in visual screening for children (mean age 53.43 years, SD ± 9.40). The panel received in advance a script with the description of three tuning competencies dimensions (instrumental, systemic, and interpersonal) for visual screening. The session was recorded in video and audio. Qualitative data were analyzed using a categorical technique. According to experts' views, six tests (35.29%) have to be included in a visual screening: distance visual acuity test, cover test, bi-prism or 4/6(Δ) prism, fusion, ocular movements, and refraction. Screening should be performed according to the child age before and after 3 years of age (17.65%). The expert panel highlighted the influence of the professional experience in the application of a screening protocol (23.53%). They also showed concern about the false negatives control (23.53%). Instrumental competencies were the most cited (54.09%), followed by interpersonal (29.51%) and systemic (16.4%). Orthoptists should have professional experience before starting to apply a screening protocol. False negative results are a concern that has to be more thoroughly investigated. The proposed framework focuses on core competencies highlighted by the expert panel. Competencies programs could be important do develop better screening programs.

  17. Clinical application of three-dimensional printing to the management of complex univentricular hearts with abnormal systemic or pulmonary venous drainage.

    PubMed

    McGovern, Eimear; Kelleher, Eoin; Snow, Aisling; Walsh, Kevin; Gadallah, Bassem; Kutty, Shelby; Redmond, John M; McMahon, Colin J

    2017-09-01

    In recent years, three-dimensional printing has demonstrated reliable reproducibility of several organs including hearts with complex congenital cardiac anomalies. This represents the next step in advanced image processing and can be used to plan surgical repair. In this study, we describe three children with complex univentricular hearts and abnormal systemic or pulmonary venous drainage, in whom three-dimensional printed models based on CT data assisted with preoperative planning. For two children, after group discussion and examination of the models, a decision was made not to proceed with surgery. We extend the current clinical experience with three-dimensional printed modelling and discuss the benefits of such models in the setting of managing complex surgical problems in children with univentricular circulation and abnormal systemic or pulmonary venous drainage.

  18. On Assisting a Visual-Facial Affect Recognition System with Keyboard-Stroke Pattern Information

    NASA Astrophysics Data System (ADS)

    Stathopoulou, I.-O.; Alepis, E.; Tsihrintzis, G. A.; Virvou, M.

    Towards realizing a multimodal affect recognition system, we are considering the advantages of assisting a visual-facial expression recognition system with keyboard-stroke pattern information. Our work is based on the assumption that the visual-facial and keyboard modalities are complementary to each other and that their combination can significantly improve the accuracy in affective user models. Specifically, we present and discuss the development and evaluation process of two corresponding affect recognition subsystems, with emphasis on the recognition of 6 basic emotional states, namely happiness, sadness, surprise, anger and disgust as well as the emotion-less state which we refer to as neutral. We find that emotion recognition by the visual-facial modality can be aided greatly by keyboard-stroke pattern information and the combination of the two modalities can lead to better results towards building a multimodal affect recognition system.

  19. Dynamic Visualization of Co-expression in Systems Genetics Data

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    New, Joshua Ryan; Huang, Jian; Chesler, Elissa J

    2008-01-01

    Biologists hope to address grand scientific challenges by exploring the abundance of data made available through modern microarray technology and other high-throughput techniques. The impact of this data, however, is limited unless researchers can effectively assimilate such complex information and integrate it into their daily research; interactive visualization tools are called for to support the effort. Specifically, typical studies of gene co-expression require novel visualization tools that enable the dynamic formulation and fine-tuning of hypotheses to aid the process of evaluating sensitivity of key parameters. These tools should allow biologists to develop an intuitive understanding of the structure of biologicalmore » networks and discover genes which reside in critical positions in networks and pathways. By using a graph as a universal data representation of correlation in gene expression data, our novel visualization tool employs several techniques that when used in an integrated manner provide innovative analytical capabilities. Our tool for interacting with gene co-expression data integrates techniques such as: graph layout, qualitative subgraph extraction through a novel 2D user interface, quantitative subgraph extraction using graph-theoretic algorithms or by querying an optimized b-tree, dynamic level-of-detail graph abstraction, and template-based fuzzy classification using neural networks. We demonstrate our system using a real-world workflow from a large-scale, systems genetics study of mammalian gene co-expression.« less

  20. Endocrine Abnormalities in Patients with Chronic Kidney Disease.

    PubMed

    Kuczera, Piotr; Adamczak, Marcin; Wiecek, Andrzej

    2015-01-01

    In patients with chronic kidney disease the alterations of the endocrine system may arise from several causes. The kidney is the site of degradation as well as synthesis of many different hormones. Moreover, a number of concomitant pathological conditions such as inflammation, metabolic acidosis and malnutrition may participate in the pathogenesis of endocrine abnormalities in this group of patients. The most pronounced endocrine abnormalities in patients with chronic kidney disease are the deficiencies of: calcitriol, testosterone, insulin-like growth factor and, erythropoietin (EPO). Additionally accumulation of several hormones, such as: prolactin, growth hormone and insulin frequently also occur. The clinical consequences of the abovementioned endocrine abnormalities are among others: anemia, infertility and bone diseases.

  1. A comparison of two-coloured filter systems for treating visual reading difficulties.

    PubMed

    Hall, Roger; Ray, Nicola; Harries, Priscilla; Stein, John

    2013-01-01

    Visual disturbances that make it difficult to read text are often termed "visual stress". Coloured filters in spectacles may help some children overcome reading problems that are often caused by visual stress. It has been suggested that for optimal effect each child requires an individually prescribed colour for each eye, as determined in systems such as the "Harris Foundation" coloured filters. Alternatively, it has been argued that only blue or yellow filters, as used in the "Dyslexia Research Trust" (DRT) filter system, are necessary to affect the underlying physiology. A randomised, double blind trial with 73 delayed readers, was undertaken to compare changes in reading and spelling as well as irregular and non-word reading skills after 3 months of wearing either the Harris or the DRT filters. Reading improved significantly after wearing either type of filter (t = -8.4, p < 0.01), with 40% of the children improving their reading age by 6 months or more during the 3 month trial. However, spelling ability (t = 2.1, p = 0.05) and non-word reading (f = 4.7, p < 0.05) improved significantly more with the DRT than with the Harris filters. Education and rehabilitation professionals should therefore, consider coloured filters as an effective intervention for delayed readers experiencing visual stress. Any disability that impacts on a child's capacity to read has serious implications for academic development as well as the ability to participate independently in activities of daily living. One reading disability, generally termed "visual stress", is related to visual disturbances that make it difficult to read text. This research demonstrates the beneficial use of coloured filters for promoting visual reading capacity for children with visual stress. Professionals who are involved in the needs of children with reading delay, may like to consider the benefits that coloured filters can afford children with visual reading problems.

  2. A comparison of two-coloured filter systems for treating visual reading difficulties

    PubMed Central

    Hall, Roger; Ray, Nicola; Harries, Priscilla

    2013-01-01

    Purpose Visual disturbances that make it difficult to read text are often termed “visual stress”. Coloured filters in spectacles may help some children overcome reading problems that are often caused by visual stress. It has been suggested that for optimal effect each child requires an individually prescribed colour for each eye, as determined in systems such as the “Harris Foundation” coloured filters. Alternatively, it has been argued that only blue or yellow filters, as used in the “Dyslexia Research Trust” (DRT) filter system, are necessary to affect the underlying physiology. Method A randomised, double blind trial with 73 delayed readers, was undertaken to compare changes in reading and spelling as well as irregular and non-word reading skills after 3 months of wearing either the Harris or the DRT filters. Results Reading improved significantly after wearing either type of filter (t = −8.4, p < 0.01), with 40% of the children improving their reading age by 6 months or more during the 3 month trial. However, spelling ability (t = 2.1, p = 0.05) and non-word reading (f = 4.7, p < 0.05) improved significantly more with the DRT than with the Harris filters. Conclusion Education and rehabilitation professionals should therefore, consider coloured filters as an effective intervention for delayed readers experiencing visual stress. Implications for Rehabilitation Any disability that impacts on a child’s capacity to read has serious implications for academic development as well as the ability to participate independently in activities of daily living. One reading disability, generally termed “visual stress”, is related to visual disturbances that make it difficult to read text. This research demonstrates the beneficial use of coloured filters for promoting visual reading capacity for children with visual stress. Professionals who are involved in the needs of children with reading delay, may like to consider the benefits

  3. Normal Visual Acuity and Electrophysiological Contrast Gain in Adults with High-Functioning Autism Spectrum Disorder.

    PubMed

    Tebartz van Elst, Ludger; Bach, Michael; Blessing, Julia; Riedel, Andreas; Bubl, Emanuel

    2015-01-01

    A common neurodevelopmental disorder, autism spectrum disorder (ASD), is defined by specific patterns in social perception, social competence, communication, highly circumscribed interests, and a strong subjective need for behavioral routines. Furthermore, distinctive features of visual perception, such as markedly reduced eye contact and a tendency to focus more on small, visual items than on holistic perception, have long been recognized as typical ASD characteristics. Recent debate in the scientific community discusses whether the physiology of low-level visual perception might explain such higher visual abnormalities. While reports of this enhanced, "eagle-like" visual acuity contained methodological errors and could not be substantiated, several authors have reported alterations in even earlier stages of visual processing, such as contrast perception and motion perception at the occipital cortex level. Therefore, in this project, we have investigated the electrophysiology of very early visual processing by analyzing the pattern electroretinogram-based contrast gain, the background noise amplitude, and the psychophysical visual acuities of participants with high-functioning ASD and controls with equal education. Based on earlier findings, we hypothesized that alterations in early vision would be present in ASD participants. This study included 33 individuals with ASD (11 female) and 33 control individuals (12 female). The groups were matched in terms of age, gender, and education level. We found no evidence of altered electrophysiological retinal contrast processing or psychophysical measured visual acuities. There appears to be no evidence for abnormalities in retinal visual processing in ASD patients, at least with respect to contrast detection.

  4. Mosaic and Concerted Evolution in the Visual System of Birds

    PubMed Central

    Gutiérrez-Ibáñez, Cristián; Iwaniuk, Andrew N.; Moore, Bret A.; Fernández-Juricic, Esteban; Corfield, Jeremy R.; Krilow, Justin M.; Kolominsky, Jeffrey; Wylie, Douglas R.

    2014-01-01

    Two main models have been proposed to explain how the relative size of neural structures varies through evolution. In the mosaic evolution model, individual brain structures vary in size independently of each other, whereas in the concerted evolution model developmental constraints result in different parts of the brain varying in size in a coordinated manner. Several studies have shown variation of the relative size of individual nuclei in the vertebrate brain, but it is currently not known if nuclei belonging to the same functional pathway vary independently of each other or in a concerted manner. The visual system of birds offers an ideal opportunity to specifically test which of the two models apply to an entire sensory pathway. Here, we examine the relative size of 9 different visual nuclei across 98 species of birds. This includes data on interspecific variation in the cytoarchitecture and relative size of the isthmal nuclei, which has not been previously reported. We also use a combination of statistical analyses, phylogenetically corrected principal component analysis and evolutionary rates of change on the absolute and relative size of the nine nuclei, to test if visual nuclei evolved in a concerted or mosaic manner. Our results strongly indicate a combination of mosaic and concerted evolution (in the relative size of nine nuclei) within the avian visual system. Specifically, the relative size of the isthmal nuclei and parts of the tectofugal pathway covary across species in a concerted fashion, whereas the relative volume of the other visual nuclei measured vary independently of one another, such as that predicted by the mosaic model. Our results suggest the covariation of different neural structures depends not only on the functional connectivity of each nucleus, but also on the diversity of afferents and efferents of each nucleus. PMID:24621573

  5. Normal and abnormal human vestibular ocular function

    NASA Technical Reports Server (NTRS)

    Peterka, R. J.; Black, F. O.

    1986-01-01

    The major motivation of this research is to understand the role the vestibular system plays in sensorimotor interactions which result in spatial disorientation and motion sickness. A second goal was to explore the range of abnormality as it is reflected in quantitative measures of vestibular reflex responses. The results of a study of vestibular reflex measurements in normal subjects and preliminary results in abnormal subjects are presented in this report. Statistical methods were used to define the range of normal responses, and determine age related changes in function.

  6. A Review of Generic Program Visualization Systems for Introductory Programming Education

    ERIC Educational Resources Information Center

    Sorva, Juha; Karavirta, Ville; Malmi, Lauri

    2013-01-01

    This article is a survey of program visualization systems intended for teaching beginners about the runtime behavior of computer programs. Our focus is on generic systems that are capable of illustrating many kinds of programs and behaviors. We inclusively describe such systems from the last three decades and review findings from their empirical…

  7. Ophthalmological, Cognitive, Electrophysiological and MRI Assessment of Visual Processing in Preterm Children without Major Neuromotor Impairment

    ERIC Educational Resources Information Center

    O'Reilly, Michelle; Vollmer, Brigitte; Vargha-Khadem, Faraneh; Neville, Brian; Connelly, Alan; Wyatt, John; Timms, Chris; De Haan, Michelle

    2010-01-01

    Many studies report chronic deficits in visual processing in children born preterm. We investigated whether functional abnormalities in visual processing exist in children born preterm but without major neuromotor impairment (i.e. cerebral palsy). Twelve such children (less than 33 weeks gestation or birthweight less than 1000 g) without major…

  8. PALM-COEIN Nomenclature for Abnormal Uterine Bleeding.

    PubMed

    Deneris, Angela

    2016-05-01

    Approximately 30% of women will experience abnormal uterine bleeding (AUB) during their life time. Previous terms defining AUB have been confusing and imprecisely applied. As a consequence, both clinical management and research on this common problem have been negatively impacted. In 2011, the International Federation of Gynecology and Obstetrics (FIGO) Menstrual Disorders Group (FMDG) published PALM-COEIN, a new classification system for abnormal bleeding in the reproductive years. Terms such as menorrhagia, menometrorrhagia, metrorrhagia, dysfunctional uterine bleeding, polymenorrhea, oligomenorrhea, and uterine hemorrhage are no longer recommended. The PALM-COEIN system was developed to standardize nomenclature to describe the etiology and severity of AUB. A brief description of the PALM-COEIN nomenclature is presented as well as treatment options for each etiology. Clinicians will frequently encounter women with AUB and should report findings utilizing the PALM-COEIN system. © 2016 by the American College of Nurse-Midwives.

  9. The foundations of development and deprivation in the visual system.

    PubMed

    Daw, Nigel W

    2009-06-15

    The pioneering work of Torsten Wiesel and David Hubel on the development and deprivation of the visual system will be summarised, together with some comments on their influence, and some personal reminiscences by the author.

  10. Cardiac Abnormalities in Primary Hyperoxaluria

    PubMed Central

    Mookadam, Farouk; Smith, Travis; Jiamsripong, Panupong; Moustafa, Sherif E; Monico, Carla G.; Lieske, John C.; Milliner, Dawn S.

    2018-01-01

    Background In patients with primary hyperoxaluria (PH), oxalate overproduction can result in recurrent urolithiasis and nephrocalcinosis, which in some cases results in a progressive decline in renal function, oxalate retention, and systemic oxalosis involving bone, retina, arterial media, peripheral nerves, skin, and heart. Oxalosis involving the myocardium or conduction system can potentially lead to heart failure and fatal arrhythmias. Methods and Results A retrospective review of our institution’s database was conducted for all patients with a confirmed diagnosis of PH between 1/1948 and 1/2006 (n=103). Electrocardiogram (ECG) and echocardiography were used to identify cardiac abnormalities. Ninety-three patients fulfilled the inclusion criteria, 58% were male. Mean follow-up was 11.9 (median 8.8) years. In 38 patients who received an ECG or echocardiography, 31 were found to have any cardiac abnormalities. Cardiac findings correlated with decline in renal function. Conclusions Our data suggests that physicians caring for patients with PH should pay close attention to cardiac status, especially if renal function is impaired. PMID:20921818

  11. Towards Infusing Giovanni with a Semantic and Provenance Aware Visualization System

    NASA Astrophysics Data System (ADS)

    Del Rio, N.; Pinheiro da Silva, P.; Leptoukh, G. G.; Lynnes, C.

    2011-12-01

    Giovanni is a Web-based application developed by GES DISC that provides simple and intuitive ways to visualize, analyze, and access vast amounts of Earth science remote sensed data. Currently, the Giovanni visualization module is only aware of the physical links (i.e., hard-coded) between data and services and consequently cannot be easily adapted to new visualization scenarios. VisKo, a semantically enabled visualization framework, can be leveraged by Giovanni as a semantic bridge between data and visualization. VisKo relates data and visualization services at conceptual (i.e., ontological) levels and relies on reasoning systems to leverage the conceptual relationships to automatically infer physical links, facilitating an adaptable environment for new visualization scenarios. This is particularly useful for Giovanni, which has been constantly retrofitted with new visualization software packages to keep up with advancement in visualization capabilities. During our prototype integration of Giovanni with VisKo, a number of future steps were identified that if implemented could cement the integration and promote our prototype to operational status. A number of integration issues arose including the mediation of different languages used by each system to characterize datasets; VisKo relies on semantic data characterization to "match-up" data with visualization processes. It was necessary to identify mappings between Giovanni XML provenance and Proof Markup Language, which is understood by VisKo. Although a translator was implemented based on identified mappings, a more elegant solution is to develop a domain data ontology specific to Giovanni and to "align" this ontology with PML, enabling VisKo to directly ingest the semantic descriptions of Giovanni data. Additionally, the relationship between dataset components (e.g., variables and attributes) and visualization plot components (e.g., geometries, axes, titles) should also be modeled. In Giovanni, meta

  12. Method and system for determining precursors of health abnormalities from processing medical records

    DOEpatents

    None, None

    2013-06-25

    Medical reports are converted to document vectors in computing apparatus and sampled by applying a maximum variation sampling function including a fitness function to the document vectors to reduce a number of medical records being processed and to increase the diversity of the medical records being processed. Linguistic phrases are extracted from the medical records and converted to s-grams. A Haar wavelet function is applied to the s-grams over the preselected time interval; and the coefficient results of the Haar wavelet function are examined for patterns representing the likelihood of health abnormalities. This confirms certain s-grams as precursors of the health abnormality and a parameter can be calculated in relation to the occurrence of such a health abnormality.

  13. Design of an Eye Limiting Resolution Visual System Using Commercial-Off-the-Shelf Equipment

    NASA Technical Reports Server (NTRS)

    Sweet, Barbara T.; Giovannetti, Dean P.

    2008-01-01

    A feasibility study was conducted to determine if a flight simulator with an eye-limiting resolution out-the-window (OTW) visual system could be built using commercial off-the-shelf (COTS) technology and used to evaluate the visual performance of Air Force pilots in an operations context. Results of this study demonstrate that an eye limiting OTW visual system can be built using COTS technology. Further, a series of operationally-based tasks linked to clinical vision tests can be used within the synthetic environment to demonstrate a correlation and quantify the level of correlation between vision and operational aviation performance.

  14. Emergence of order in visual system development.

    PubMed Central

    Shatz, C J

    1996-01-01

    Neural connections in the adult central nervous system are highly precise. In the visual system, retinal ganglion cells send their axons to target neurons in the lateral geniculate nucleus (LGN) in such a way that axons originating from the two eyes terminate in adjacent but nonoverlapping eye-specific layers. During development, however, inputs from the two eyes are intermixed, and the adult pattern emerges gradually as axons from the two eyes sort out to form the layers. Experiments indicate that the sorting-out process, even though it occurs in utero in higher mammals and always before vision, requires retinal ganglion cell signaling; blocking retinal ganglion cell action potentials with tetrodotoxin prevents the formation of the layers. These action potentials are endogenously generated by the ganglion cells, which fire spontaneously and synchronously with each other, generating "waves" of activity that travel across the retina. Calcium imaging of the retina shows that the ganglion cells undergo correlated calcium bursting to generate the waves and that amacrine cells also participate in the correlated activity patterns. Physiological recordings from LGN neurons in vitro indicate that the quasiperiodic activity generated by the retinal ganglion cells is transmitted across the synapse between ganglion cells to drive target LGN neurons. These observations suggest that (i) a neural circuit within the immature retina is responsible for generating specific spatiotemporal patterns of neural activity; (ii) spontaneous activity generated in the retina is propagated across central synapses; and (iii) even before the photoreceptors are present, nerve cell function is essential for correct wiring of the visual system during early development. Since spontaneously generated activity is known to be present elsewhere in the developing CNS, this process of activity-dependent wiring could be used throughout the nervous system to help refine early sets of neural connections into

  15. Fifteen-minute consultation-the child with a developmental disability: is there an ocular or visual abnormality?

    PubMed

    Salt, Alison; Sargent, Jenefer

    2017-12-01

    To present a structured approach for an outpatient consultation for a child with developmental disability who may have an ocular or visual disorder. Review of relevant literature and description of the approach to ocular and visual assessment which could be used by any paediatrician. A systematic approach to history, observation and examination of a child with a developmental disability will assist in identifying a possible visual problem. A structured referral letter will ensure that the child will receive the most appropriate assessment to clarify the problem and appropriate management in the eye clinic. © Article author(s) (or their employer(s) unless otherwise stated in the text of the article) 2017. All rights reserved. No commercial use is permitted unless otherwise expressly granted.

  16. Abnormal pressures as hydrodynamic phenomena

    USGS Publications Warehouse

    Neuzil, C.E.

    1995-01-01

    So-called abnormal pressures, subsurface fluid pressures significantly higher or lower than hydrostatic, have excited speculation about their origin since subsurface exploration first encountered them. Two distinct conceptual models for abnormal pressures have gained currency among earth scientists. The static model sees abnormal pressures generally as relict features preserved by a virtual absence of fluid flow over geologic time. The hydrodynamic model instead envisions abnormal pressures as phenomena in which flow usually plays an important role. This paper develops the theoretical framework for abnormal pressures as hydrodynamic phenomena, shows that it explains the manifold occurrences of abnormal pressures, and examines the implications of this approach. -from Author

  17. Acute visual neglect and extinction: distinct functional state of the visuospatial attention system.

    PubMed

    Umarova, Roza M; Saur, Dorothee; Kaller, Christoph P; Vry, Magnus-Sebastian; Glauche, Volkmar; Mader, Irina; Hennig, Jürgen; Weiller, Cornelius

    2011-11-01

    The neural mechanisms underlying spatial neglect are still disputed. Abnormal left parietal hyperactivation is proposed to lead to the rightward attentional bias, a clinical hallmark of neglect. Extinction, another deficit of visuospatial attention, is regarded as either a 'mild' form of neglect or a distinct syndrome. Although both neglect and extinction are typical syndromes of acute right hemispheric stroke, all imaging studies investigating these syndromes were conducted at least several weeks after stroke onset, in a phase when brain reorganization has already progressed. The present study aimed at comparing the activation patterns in acute stroke patients with neglect and extinction during visuospatial processing. Using functional magnetic resonance imaging, we examined the functional state of the attention system in 33 patients with a first ever stroke (53 ± 5 h after stroke onset) and age-matched healthy subjects (n = 15). All patients had embolic infarcts within the territory of the right middle cerebral artery. Patients were divided into three groups: (i) normal visuospatial processing (control patients, n = 11); (ii) patients with visual extinction but with no signs of neglect (n = 9); and (iii) patients with visual neglect (n = 13). While undergoing functional magnetic resonance imaging, patients performed a Posner-like task for visuospatial attention with detection of the targets in the left and right visual hemifields. Patients with neglect showed the expected imbalance in the left versus right parietal activation, which however, was present also in control and extinction patients, thus representing an epiphenomenon of the acute structural lesion in the right hemisphere. Compared with control patients, neglect was characterized by reduced activation in the right parietal and lateral occipital cortex, as well as in the left frontal eye field. In contrast, the activation pattern in patients with extinction differed from all other groups by an increased

  18. Using Correlative Properties of Neighboring Pixels to Enhance Contrast-to-Noise Ratio of Abnormal Hippocampus in Patients With Intractable Epilepsy and Mesial Temporal Sclerosis.

    PubMed

    Parsons, Matthew S; Sharma, Aseem; Hildebolt, Charles

    2018-06-12

    To test whether an image-processing algorithm can aid in visualization of mesial temporal sclerosis on magnetic resonance imaging by selectively increasing contrast-to-noise ratio (CNR) between abnormal hippocampus and normal brain. In this Institutional Review Board-approved and Health Insurance Portability and Accountability Act-compliant study, baseline coronal fluid-attenuated inversion recovery images of 18 adults (10 females, eight males; mean age 41.2 years) with proven mesial temporal sclerosis were processed using a custom algorithm to produce corresponding enhanced images. Average (Hmean) and maximum (Hmax) CNR for abnormal hippocampus were calculated relative to normal ipsilateral white matter. CNR values for normal gray matter (GM) were similarly calculated using ipsilateral cingulate gyrus as the internal control. To evaluate effect of image processing on visual conspicuity of hippocampal signal alteration, a neuroradiologist masked to the side of hippocampal abnormality rated signal intensity (SI) of hippocampi on baseline and enhanced images using a five-point scale (definitely abnormal to definitely normal). Differences in Hmean, Hmax, GM, and SI ratings for abnormal hippocampi on baseline and enhanced images were assessed for statistical significance. Both Hmean and Hmax were significantly higher in enhanced images as compared to baseline images (p < 0.0001 for both). There was no significant difference in the GM between baseline and enhanced images (p = 0.9375). SI ratings showed a more confident identification of abnormality on enhanced images (p = 0.0001). Image-processing resulted in increased CNR of abnormal hippocampus without affecting the CNR of normal gray matter. This selective increase in conspicuity of abnormal hippocampus was associated with more confident identification of hippocampal signal alteration. Copyright © 2018 Academic Radiology. Published by Elsevier Inc. All rights reserved.

  19. Streptozotocin induced oxidative stress, innate immune system responses and behavioral abnormalities in male mice.

    PubMed

    Amiri, Shayan; Haj-Mirzaian, Arya; Momeny, Majid; Amini-Khoei, Hossein; Rahimi-Balaei, Maryam; Poursaman, Simin; Rastegar, Mojgan; Nikoui, Vahid; Mokhtari, Tahmineh; Ghazi-Khansari, Mahmoud; Hosseini, Mir-Jamal

    2017-01-06

    Recent evidence indicates the involvement of inflammatory factors and mitochondrial dysfunction in the etiology of psychiatric disorders such as anxiety and depression. To investigate the possible role of mitochondrial-induced sterile inflammation in the co-occurrence of anxiety and depression, in this study, we treated adult male mice with the intracerebroventricular (i.c.v.) infusion of a single low dose of streptozotocin (STZ, 0.2mg/mouse). Using valid and qualified behavioral tests for the assessment of depressive and anxiety-like behaviors, we showed that STZ-treated mice exhibited behaviors relevant to anxiety and depression 24h following STZ treatment. We observed that the co-occurrence of anxiety and depressive-like behaviors in animals were associated with abnormal mitochondrial function, nitric oxide overproduction and, the increased activity of cytosolic phospholipase A 2 (cPLA 2 ) in the hippocampus. Further, STZ-treated mice had a significant upregulation of genes associated with the innate immune system such as toll-like receptors 2 and 4. Pathological evaluations showed no sign of neurodegeneration in the hippocampus of STZ-treated mice. Results of this study revealed that behavioral abnormalities provoked by STZ, as a cytotoxic agent that targets mitochondria and energy metabolism, are associated with abnormal mitochondrial activity and, consequently the initiation of innate-inflammatory responses in the hippocampus. Our findings highlight the role of mitochondria and innate immunity in the formation of sterile inflammation and behaviors relevant to anxiety and depression. Also, we have shown that STZ injection (i.c.v.) might be an animal model for depression and anxiety disorders based on sterile inflammation. Copyright © 2016 IBRO. Published by Elsevier Ltd. All rights reserved.

  20. A WebGIS-based system for analyzing and visualizing air quality data for Shanghai Municipality

    NASA Astrophysics Data System (ADS)

    Wang, Manyi; Liu, Chaoshun; Gao, Wei

    2014-10-01

    An online visual analytical system based on Java Web and WebGIS for air quality data for Shanghai Municipality was designed and implemented to quantitatively analyze and qualitatively visualize air quality data. By analyzing the architecture of WebGIS and Java Web, we firstly designed the overall scheme for system architecture, then put forward the software and hardware environment and also determined the main function modules for the system. The visual system was ultimately established with the DIV + CSS layout method combined with JSP, JavaScript, and some other computer programming languages based on the Java programming environment. Moreover, Struts, Spring, and Hibernate frameworks (SSH) were integrated in the system for the purpose of easy maintenance and expansion. To provide mapping service and spatial analysis functions, we selected ArcGIS for Server as the GIS server. We also used Oracle database and ESRI file geodatabase to store spatial data and non-spatial data in order to ensure the data security. In addition, the response data from the Web server are resampled to implement rapid visualization through the browser. The experimental successes indicate that this system can quickly respond to user's requests, and efficiently return the accurate processing results.

  1. Visual Confirmation (VICON) of Takeoff Clearance Signal System Impact Study

    DOT National Transportation Integrated Search

    1980-11-01

    A study was performed to evaluate the impact on airport capacity and voice communications of the Visual Confirmation of Takeoff Clearance (VICON) Signal System. Befoe-and-after test data collection and analysis were conducted at Bradley International...

  2. Conceptual design study for a teleoperator visual system, phase 1

    NASA Technical Reports Server (NTRS)

    Adams, D.; Grant, C.; Johnson, C.; Meirick, R.; Polhemus, C.; Ray, A.; Rittenhouse, D.; Skidmore, R.

    1972-01-01

    Results are reported for work performed during the first phase of the conceptual design study for a teleoperator visual system. This phase consists of four tasks: General requirements, concept development, subsystem requirements and analysis, and concept evaluation.

  3. The foundations of development and deprivation in the visual system

    PubMed Central

    Daw, Nigel W

    2009-01-01

    The pioneering work of Torsten Wiesel and David Hubel on the development and deprivation of the visual system will be summarised, together with some comments on their influence, and some personal reminiscences by the author. PMID:19221122

  4. The visual system of diurnal raptors: updated review.

    PubMed

    González-Martín-Moro, J; Hernández-Verdejo, J L; Clement-Corral, A

    2017-05-01

    Diurnal birds of prey (raptors) are considered the group of animals with highest visual acuity (VA). The purpose of this work is to review all the information recently published about the visual system of this group of animals. A bibliographic search was performed in PubMed. The algorithm used was (raptor OR falcon OR kestrel OR hawk OR eagle) AND (vision OR «visual acuity» OR eye OR macula OR retina OR fovea OR «nictitating membrane» OR «chromatic vision» OR ultraviolet). The search was restricted to the «Title» and «Abstract» fields, and to non-human species, without time restriction. The proposed algorithm located 97 articles. Birds of prey are endowed with the highest VA of the animal kingdom. However most of the works study one individual or a small group of individuals, and the methodology is heterogeneous. The most studied bird is the Peregrine falcon (Falco peregrinus), with an estimated VA of 140 cycles/degree. Some eagles are endowed with similar VA. The tubular shape of the eye, the large pupil, and a high density of photoreceptors make this extraordinary VA possible. In some species, histology and optic coherence tomography demonstrate the presence of 2foveas. The nasal fovea (deep fovea) has higher VA. Nevertheless, the exact function of each fovea is unknown. The vitreous contained in the deep fovea could behave as a third lens, adding some magnification to the optic system. Copyright © 2017 Sociedad Española de Oftalmología. Publicado por Elsevier España, S.L.U. All rights reserved.

  5. A GUI visualization system for airborne lidar image data to reconstruct 3D city model

    NASA Astrophysics Data System (ADS)

    Kawata, Yoshiyuki; Koizumi, Kohei

    2015-10-01

    A visualization toolbox system with graphical user interfaces (GUIs) was developed for the analysis of LiDAR point cloud data, as a compound object oriented widget application in IDL (Interractive Data Language). The main features in our system include file input and output abilities, data conversion capability from ascii formatted LiDAR point cloud data to LiDAR image data whose pixel value corresponds the altitude measured by LiDAR, visualization of 2D/3D images in various processing steps and automatic reconstruction ability of 3D city model. The performance and advantages of our graphical user interface (GUI) visualization system for LiDAR data are demonstrated.

  6. Visual Impairment Screening at the Geriatric Frailty Clinic for Assessment of Frailty and Prevention of Disability at the Gérontopôle.

    PubMed

    Soler, V; Sourdet, S; Balardy, L; Abellan van Kan, G; Brechemier, D; Rougé-Bugat, M E; Tavassoli, N; Cassagne, M; Malecaze, F; Nourhashémi, F; Vellas, B

    2016-01-01

    To evaluate visual performance and factors associated with abnormal vision in patients screened for frailty at the Geriatric Frailty Clinic (GFC) for Assessment of Frailty and Prevention of Disability at Toulouse University Hospital. Retrospective, observational cross-sectional, single-centre study. Institutional practice. Patients were screened for frailty during a single-day hospital stay between October 2011 and October 2014 (n = 1648). Collected medical records included sociodemographic data (including living environment and educational level), anthropometric data, and clinical data. The general evaluation included the patient's functional status using the Activities of Daily Living (ADL) scale and the Instrumental Activity of Daily Living (IADL) scale, the Mini-Mental State Examination (MMSE) for cognition testing, and the Short Physical Performance Battery (SPPB) for physical performance. We also examined Body Mass Index (BMI), the Mini-Nutritional Assessment (MNA), and the Hearing Handicap Inventory for the Elderly Screening (HHIE-S) tool. The ophthalmologic evaluation included assessing visual acuity using the Snellen decimal chart for distant vision, and the Parinaud chart for near vision. Patients were divided into groups based on normal distant/near vision (NDV and NNV groups) and abnormal distant/near vision (ADV and ANV groups). Abnormal distant or near vision was defined as visual acuity inferior to 20/40 or superior to a Parinaud score of 2, in at least one eye. Associations with frailty-associated factors were evaluated in both groups. The mean age of the population was 82.6 ± 6.2 years. The gender distribution was 1,061 females (64.4%) and 587 males (35.6%). According to the Fried criteria, 619 patients (41.1%) were pre-frail and 771 (51.1%) were frail. Distant and near vision data were available for 1425 and 1426 patients, respectively. Distant vision was abnormal for 437 patients (30.7%). Near vision was abnormal for 199 patients (14%). Multiple

  7. Development and experimental validation of computational methods to simulate abnormal thermal and structural environments

    NASA Astrophysics Data System (ADS)

    Moya, J. L.; Skocypec, R. D.; Thomas, R. K.

    1993-09-01

    Over the past 40 years, Sandia National Laboratories (SNL) has been actively engaged in research to improve the ability to accurately predict the response of engineered systems to abnormal thermal and structural environments. These engineered systems contain very hazardous materials. Assessing the degree of safety/risk afforded the public and environment by these engineered systems, therefore, is of upmost importance. The ability to accurately predict the response of these systems to accidents (to abnormal environments) is required to assess the degree of safety. Before the effect of the abnormal environment on these systems can be determined, it is necessary to ascertain the nature of the environment. Ascertaining the nature of the environment, in turn, requires the ability to physically characterize and numerically simulate the abnormal environment. Historically, SNL has demonstrated the level of safety provided by these engineered systems by either of two approaches: a purely regulatory approach, or by a probabilistic risk assessment (PRA). This paper will address the latter of the two approaches.

  8. Error quantification of abnormal extreme high waves in Operational Oceanographic System in Korea

    NASA Astrophysics Data System (ADS)

    Jeong, Sang-Hun; Kim, Jinah; Heo, Ki-Young; Park, Kwang-Soon

    2017-04-01

    In winter season, large-height swell-like waves have occurred on the East coast of Korea, causing property damages and loss of human life. It is known that those waves are generated by a local strong wind made by temperate cyclone moving to eastward in the East Sea of Korean peninsula. Because the waves are often occurred in the clear weather, in particular, the damages are to be maximized. Therefore, it is necessary to predict and forecast large-height swell-like waves to prevent and correspond to the coastal damages. In Korea, an operational oceanographic system (KOOS) has been developed by the Korea institute of ocean science and technology (KIOST) and KOOS provides daily basis 72-hours' ocean forecasts such as wind, water elevation, sea currents, water temperature, salinity, and waves which are computed from not only meteorological and hydrodynamic model (WRF, ROMS, MOM, and MOHID) but also wave models (WW-III and SWAN). In order to evaluate the model performance and guarantee a certain level of accuracy of ocean forecasts, a Skill Assessment (SA) system was established as a one of module in KOOS. It has been performed through comparison of model results with in-situ observation data and model errors have been quantified with skill scores. Statistics which are used in skill assessment are including a measure of both errors and correlations such as root-mean-square-error (RMSE), root-mean-square-error percentage (RMSE%), mean bias (MB), correlation coefficient (R), scatter index (SI), circular correlation (CC) and central frequency (CF) that is a frequency with which errors lie within acceptable error criteria. It should be utilized simultaneously not only to quantify an error but also to improve an accuracy of forecasts by providing a feedback interactively. However, in an abnormal phenomena such as high-height swell-like waves in the East coast of Korea, it requires more advanced and optimized error quantification method that allows to predict the abnormal

  9. Visualization of Computational Fluid Dynamics

    NASA Technical Reports Server (NTRS)

    Gerald-Yamasaki, Michael; Hultquist, Jeff; Bryson, Steve; Kenwright, David; Lane, David; Walatka, Pamela; Clucas, Jean; Watson, Velvin; Lasinski, T. A. (Technical Monitor)

    1995-01-01

    Scientific visualization serves the dual purpose of exploration and exposition of the results of numerical simulations of fluid flow. Along with the basic visualization process which transforms source data into images, there are four additional components to a complete visualization system: Source Data Processing, User Interface and Control, Presentation, and Information Management. The requirements imposed by the desired mode of operation (i.e. real-time, interactive, or batch) and the source data have their effect on each of these visualization system components. The special requirements imposed by the wide variety and size of the source data provided by the numerical simulation of fluid flow presents an enormous challenge to the visualization system designer. We describe the visualization system components including specific visualization techniques and how the mode of operation and source data requirements effect the construction of computational fluid dynamics visualization systems.

  10. Efficient encoding of motion is mediated by gap junctions in the fly visual system.

    PubMed

    Wang, Siwei; Borst, Alexander; Zaslavsky, Noga; Tishby, Naftali; Segev, Idan

    2017-12-01

    Understanding the computational implications of specific synaptic connectivity patterns is a fundamental goal in neuroscience. In particular, the computational role of ubiquitous electrical synapses operating via gap junctions remains elusive. In the fly visual system, the cells in the vertical-system network, which play a key role in visual processing, primarily connect to each other via axonal gap junctions. This network therefore provides a unique opportunity to explore the functional role of gap junctions in sensory information processing. Our information theoretical analysis of a realistic VS network model shows that within 10 ms following the onset of the visual input, the presence of axonal gap junctions enables the VS system to efficiently encode the axis of rotation, θ, of the fly's ego motion. This encoding efficiency, measured in bits, is near-optimal with respect to the physical limits of performance determined by the statistical structure of the visual input itself. The VS network is known to be connected to downstream pathways via a subset of triplets of the vertical system cells; we found that because of the axonal gap junctions, the efficiency of this subpopulation in encoding θ is superior to that of the whole vertical system network and is robust to a wide range of signal to noise ratios. We further demonstrate that this efficient encoding of motion by this subpopulation is necessary for the fly's visually guided behavior, such as banked turns in evasive maneuvers. Because gap junctions are formed among the axons of the vertical system cells, they only impact the system's readout, while maintaining the dendritic input intact, suggesting that the computational principles implemented by neural circuitries may be much richer than previously appreciated based on point neuron models. Our study provides new insights as to how specific network connectivity leads to efficient encoding of sensory stimuli.

  11. Fetal Alcohol Spectrum Disorders and Abnormal Neuronal Plasticity

    PubMed Central

    Medina, Alexandre E.

    2012-01-01

    The ingestion of alcohol during pregnancy can result in a group of neurobehavioral abnormalities collectively known as fetal alcohol spectrum disorders (FASD). During the past decade, studies using animal models indicated that early alcohol exposure can dramatically affect neuronal plasticity, an essential property of the central nervous system responsible for the normal wiring of the brain and involved in processes such as learning and memory. The abnormalities in neuronal plasticity caused by alcohol can explain many of the neurobehavioral deficits observed in FASD. Conversely, improving neuronal plasticity may have important therapeutic benefits. In this review, the author discuss the mechanisms that lead to these abnormalities and comment on recent pharmacological approaches that have been showing promising results in improving neuronal plasticity in FASD. PMID:21383101

  12. A navigation system for the visually impaired using colored navigation lines and RFID tags.

    PubMed

    Seto, First Tatsuya

    2009-01-01

    In this paper, we describe about a developed navigation system that supports the independent walking of the visually impaired in the indoor space. Our developed instrument consists of a navigation system and a map information system. These systems are installed on a white cane. Our navigation system can follow a colored navigation line that is set on the floor. In this system, a color sensor installed on the tip of a white cane senses the colored navigation line, and the system informs the visually impaired that he/she is walking along the navigation line by vibration. The color recognition system is controlled by a one-chip microprocessor and this system can discriminate 6 colored navigation lines. RFID tags and a receiver for these tags are used in the map information system. The RFID tags and the RFID tag receiver are also installed on a white cane. The receiver receives tag information and notifies map information to the user by mp3 formatted pre-recorded voice. Three normal subjects who were blindfolded with an eye mask were tested with this system. All of them were able to walk along the navigation line. The performance of the map information system was good. Therefore, our system will be extremely valuable in supporting the activities of the visually impaired.

  13. A mobile phone system to find crosswalks for visually impaired pedestrians

    PubMed Central

    Shen, Huiying; Chan, Kee-Yip; Coughlan, James; Brabyn, John

    2010-01-01

    Urban intersections are the most dangerous parts of a blind or visually impaired pedestrian’s travel. A prerequisite for safely crossing an intersection is entering the crosswalk in the right direction and avoiding the danger of straying outside the crosswalk. This paper presents a proof of concept system that seeks to provide such alignment information. The system consists of a standard mobile phone with built-in camera that uses computer vision algorithms to detect any crosswalk visible in the camera’s field of view; audio feedback from the phone then helps the user align him/herself to it. Our prototype implementation on a Nokia mobile phone runs in about one second per image, and is intended for eventual use in a mobile phone system that will aid blind and visually impaired pedestrians in navigating traffic intersections. PMID:20411035

  14. Symptoms related to glaucomatous visual field abnormalities among male Japanese workers in a population-based setting.

    PubMed

    Tatemichi, Masayuki; Nakano, Tadashi; Hayashi, Takeshi; Tanaka, Katsutoshi; Hiro, Hisanori; Miyamoto, Toshiaki; Aratake, Miho; Nishinoue, Norihide; Yamazaki, Akira; Nakadate, Toshio; Sugita, Minoru

    2012-09-01

    To identify symptoms potentially related to glaucomatous visual field abnormalities (VFAs) in a population-based setting, and to assess the applicability of using these symptoms to identify persons at risk of developing glaucoma. In this study, 10,214 Japanese male general workers (mean age, 45.3±8.8 years) filled out a self-administered questionnaire and underwent frequency doubling technology (FDT) perimetry testing. The questionnaire inquired about whether the participant was suffering from any of nine symptoms, with scores for each response graded on a four-item Likert scale: 0 (none), 1 (rarely), 2 (sometimes), and 3 (always). Results from the questionnaire were compared among three groups: participants without any VFAs (9767), participants with VFAs as determined by the FDT test (FDT-VFA; 447), and 227 participants (of the 447 FDT-VFA participants) with glaucomatous VFAs who were newly diagnosed by ophthalmologic examinations. The mean summed scores for the total items were significantly (p<0.01) higher in FDT- and glaucomatous VFA groups than in normal subjects. In particular, responses citing the symptoms 'feeling of something in the front of the eye' and 'feeling of hardness to see in dark places' were significantly (p<0.05) more frequent in subjects with FDT- and glaucomatous VFAs than among normal participants. However, the respective areas under the receiver operating characteristic curve of summed scores for the nine total items and for the two items which showed significant differences for the glaucoma groups were 0.57 (95% confidence interval=0.53-0.60) and 0.58 (95% confidence interval=0.54-0.61). Although the symptoms 'feeling of hardness to see in dark places' and 'feeling of something in the front of the eye' could be associated with glaucomatous VFA in a population-based setting, inquiring about symptoms is of little aid in identifying subjects with glaucomatous VFA as a strategy for public health. © 2010 The Authors. Journal compilation

  15. Flight crew exposure to ozone concentrations affecting the visual system.

    PubMed

    Daubs, J

    1980-02-01

    To estimate the potential for ozone (O3) effects on the human visual system in flight, O3 concentrations in Boeing 747-100 cockpits were measured during routine flights between London and the United States. From a review of previous reports, it appears that O3 may have both beneficial and harmful effects but that further studies of the visual system responses to O3 are needed before the present findings of 0.030 parts per million (ppm) mean O3, 0.200 ppm maximum O3, and 0.261 ppm-hours average cumulative O3 exposure can be effectively evaluated. Unexpectedly high O3 concentrations were encountered at altitudes below 18,000 feet and, at times, the O3 concentration was observed to decrease as flight level was increased. The clinical, operational, and policy implications of these findings are discussed.

  16. Scientific Visualization & Modeling for Earth Systems Science Education

    NASA Technical Reports Server (NTRS)

    Chaudhury, S. Raj; Rodriguez, Waldo J.

    2003-01-01

    Providing research experiences for undergraduate students in Earth Systems Science (ESS) poses several challenges at smaller academic institutions that might lack dedicated resources for this area of study. This paper describes the development of an innovative model that involves students with majors in diverse scientific disciplines in authentic ESS research. In studying global climate change, experts typically use scientific visualization techniques applied to remote sensing data collected by satellites. In particular, many problems related to environmental phenomena can be quantitatively addressed by investigations based on datasets related to the scientific endeavours such as the Earth Radiation Budget Experiment (ERBE). Working with data products stored at NASA's Distributed Active Archive Centers, visualization software specifically designed for students and an advanced, immersive Virtual Reality (VR) environment, students engage in guided research projects during a structured 6-week summer program. Over the 5-year span, this program has afforded the opportunity for students majoring in biology, chemistry, mathematics, computer science, physics, engineering and science education to work collaboratively in teams on research projects that emphasize the use of scientific visualization in studying the environment. Recently, a hands-on component has been added through science student partnerships with school-teachers in data collection and reporting for the GLOBE Program (GLobal Observations to Benefit the Environment).

  17. Calibration validation for the new generation runway visual range system

    DOT National Transportation Integrated Search

    2000-07-01

    A forward scattermeter, consisting of transmitter and receiver heads mounted on a fork, is used in the New Genreration Runway Visual Range (NGRVR) System to assess the clarity of the atmosphere. The scattermeter is calibrated by comparison with refer...

  18. Purtscher-like retinopathy in systemic lupus erythematosus.

    PubMed

    Wu, Chan; Dai, Rongping; Dong, Fangtian; Wang, Qian

    2014-12-01

    To investigate clinical characteristics of Purtscher-like retinopathy and its clinical implications among patients with systemic lupus erythematosus (SLE). Observational case series. setting: Tertiary medical center. patient population: Patients with SLE who were diagnosed with Purtscher-like retinopathy between 2002 and 2013. observation procedures: Assessment and follow-up in the ophthalmology department. main outcome measure: Visual acuity and funduscopic examination at presentation and at 6 month follow-up, with analysis of the association between Purtscher-like retinopathy and other systemic involvement of SLE and overall disease activity. Among 5688 patients with SLE evaluated, 8 cases of Purtscher-like retinopathy were diagnosed. Typical fundus abnormalities included Purtscher flecken, cotton-wool spots, retinal hemorrhages, macular edema, optic disk swelling, and a pseudo-cherry red spot. Fluorescein angiography abnormalities included areas of capillary nonperfusion corresponding to the retinal whitening, late leakage, peripapillary staining, precapillary occlusion, and slower filling of vessels. The prevalence of central nervous system lupus was significantly higher among those with Purtscher-like retinopathy (6/8) than among 240 patients randomly sampled from those without Purtscher-like retinopathy. A very high SLE Disease Activity Index (≥20) was present in all 8 patients with Purtscher-like retinopathy. All patients received corticosteroids combined with immunosuppressants. For the majority of patients, optic atrophy developed during follow-up with persistent low visual acuity. As a rare and severe ophthalmic complication of SLE, Purtscher-like retinopathy was associated with central nervous system lupus and highly active disease. Visual acuity recovery was usually poor despite prompt treatment. Copyright © 2014 Elsevier Inc. All rights reserved.

  19. Cerebral visual impairment in children: Causes and associated ophthalmological problems.

    PubMed

    Pehere, Niranjan; Chougule, Pratik; Dutton, Gordon N

    2018-06-01

    The aim of this study is to identify common causes, associated ophthalmological abnormalities, and systemic comorbidities in children in Andhra Pradesh, India, with cerebral visual impairment (CVI). A retrospective review of case records of all children aged <16 years with diagnosis of CVI seen between January 2016 and December 2016 was carried out. Data were collected for their age, gender, cause of CVI, refraction, accommodation, anterior and posterior segment examination findings, and systemic problems. A total of 124 patients were identified and studied (80 boys and 44 girls, mean age 5.23 years, 44.8% aged <2 years). The most common causes of CVI were hypoxic-ischemic encephalopathy (HIE) (34.4%), undetermined etiology (32.8%), neonatal seizures, and infantile spasms (16% each). The most common presenting complaints were poor vision (76%) and squint (11.2%). Profound visual impairment was seen in 88.8%, and 11.2% had high functioning CVI. Fifty-eight (46.4%) patients had significant refractive errors, 40 (32.25%) had strabismus, 4 (3.2%) had visually significant cataract, and 40 (32%) had optic atrophy. Motor delay was observed in 39.5%, speech delay was evident in 22.4%, and cognitive delay in 16%. HIE is the most common cause (one-third) of CVI in our population, and the majority of them presented at age <2 years (44.8%) with profound visual impairment (88.8%). A significant number of them have treatable ophthalmic conditions such as refractive errors (46.4%), accommodative insufficiency (12.1%), and cataract (3.2%), and more than one-third of them also have delay in other areas of development.

  20. Envision: An interactive system for the management and visualization of large geophysical data sets

    NASA Technical Reports Server (NTRS)

    Searight, K. R.; Wojtowicz, D. P.; Walsh, J. E.; Pathi, S.; Bowman, K. P.; Wilhelmson, R. B.

    1995-01-01

    Envision is a software project at the University of Illinois and Texas A&M, funded by NASA's Applied Information Systems Research Project. It provides researchers in the geophysical sciences convenient ways to manage, browse, and visualize large observed or model data sets. Envision integrates data management, analysis, and visualization of geophysical data in an interactive environment. It employs commonly used standards in data formats, operating systems, networking, and graphics. It also attempts, wherever possible, to integrate with existing scientific visualization and analysis software. Envision has an easy-to-use graphical interface, distributed process components, and an extensible design. It is a public domain package, freely available to the scientific community.