Distribution by Scientific Domains
Distribution within Medical Sciences

Terms modified by Visual

  • visual ability
  • visual acuity
  • visual acuity loss
  • visual acuity measurement
  • visual aid
  • visual analog
  • visual analog pain scale
  • visual analog scale
  • visual analogue
  • visual analogue pain scale
  • visual analogue scale
  • visual analogue scale score
  • visual analogue score
  • visual analysis
  • visual appearance
  • visual approach
  • visual area
  • visual assessment
  • visual attention
  • visual attribute
  • visual aura
  • visual awareness
  • visual behaviour
  • visual census
  • visual censuse
  • visual change
  • visual communication
  • visual comparison
  • visual complaints
  • visual condition
  • visual control
  • visual cortex
  • visual cue
  • visual culture
  • visual cycle
  • visual defect
  • visual deficit
  • visual deprivation
  • visual detection
  • visual deterioration
  • visual development
  • visual discrimination
  • visual disorders
  • visual display
  • visual disturbance
  • visual dysfunction
  • visual ecology
  • visual effects
  • visual enhancement
  • visual environment
  • visual estimate
  • visual estimation
  • visual evaluation
  • visual evidence
  • visual evoked potential
  • visual examination
  • visual experience
  • visual exploration
  • visual feature
  • visual feedback
  • visual field
  • visual field assessment
  • visual field constriction
  • visual field defect
  • visual field examination
  • visual field loss
  • visual field test
  • visual field testing
  • visual form
  • visual function
  • visual function questionnaire
  • visual functioning
  • visual hallucination
  • visual image
  • visual imagery
  • visual impairment
  • visual impression
  • visual improvement
  • visual information
  • visual input
  • visual inspection
  • visual interpretation
  • visual localization
  • visual loss
  • visual media
  • visual memory
  • visual method
  • visual motion
  • visual object recognition
  • visual observation
  • visual outcome
  • visual pathway
  • visual pattern
  • visual perception
  • visual perceptual ability
  • visual performance
  • visual pigment
  • visual presentation
  • visual problem
  • visual process
  • visual processing
  • visual prognosis
  • visual property
  • visual quality
  • visual rating
  • visual reaction time
  • visual recognition
  • visual recovery
  • visual regions
  • visual rehabilitation
  • visual representation
  • visual response
  • visual retention test
  • visual scale
  • visual scene
  • visual scoring
  • visual screening
  • visual search
  • visual search task
  • visual sensitivity
  • visual signal
  • visual stimulation
  • visual stimulus
  • visual stream
  • visual survey
  • visual symptom
  • visual system
  • visual target
  • visual task
  • visual testing
  • visual tracking
  • visual world

  • Selected Abstracts


    BRAIN PATHOLOGY, Issue 1 2009
    Stephan Frank
    First page of article [source]

    Are the cognitive functions of children with Down syndrome related to their participation?

    Aim, There is a lack of investigation into the functional developmental profile of children with Down syndrome. On the basis of current international health paradigms, the purpose of this study was to assess the developmental profile of these children. Method, Sixty children (33 males, 27 females) with Down syndrome (age range 6,16y; mean age 9y 3mo, SD 28.8mo), who had received standard, holistic, early intervention, were assessed. Of these, 42 (70%) had congenital anomalies, 12 had severe congenital heart defects. Participants were assessed on measures of cognitive function (Beery,Buktenica Developmental Test of Visual,Motor Integration; Stanford,Binet Intelligence Scale) and participation (Vineland Adaptive Behaviour Scales). Results, No difference was found on any measure on the basis of severity of congenital anomaly. Results showed improvements in age-related body function and correlations between specific body functions and participation. No decline in IQ was found with age, and significant correlations between IQ and all other measures were noted. Although sex differences were found in the body functions of short-term memory and motor function, no difference in measures of activity performance and participation was found. Interpretation, Our findings emphasize the need for paediatric Down syndrome intervention to encourage improved body functions while emphasizing the acquisition of functional skills that enable enhanced participation in age-appropriate activities. [source]

    Threshold electrical stimulation (TES) in ambulant children with CP: a randomized double-blind placebo-controlled clinical trial

    Christineí Dali MD
    A randomized double-blind placebo-controlled clinical trial was carried out to determine whether a group of stable children with cerebral palsy (36 males, 21 females; mean age 10 years 11 months, range 5 to 18 years) would improve their motor skills after 12 months of threshold electrical stimulation (TES). Two thirds received active and one third received inactive stimulators. For the primary outcome we constructed a set of plausible motor function tests and studied the change in summary indices of the performance measurements. Tests were videotaped and assessed blindly to record qualitative changes that might not be reflected in performance measurements. We also judged range of motion, degree of spasticity, and muscle growth measured by CT. Fifty seven of 82 outpatients who were able to walk at least with a walker, completed all 12 months of treatment (hemiplegia n=25, diplegia n=32). There was no significant difference between active and placebo treatment in any of the tested groups, nor combined. Visual and subjective assessments favoured TES (ns), whereas objective indices showed the opposite trend. We conclude that TES in these patients did not have any significant clinical effect during the test period. [source]

    Visual, auditory and cross-modal processing of linguistic and nonlinguistic temporal patterns among adult dyslexic readers

    DYSLEXIA, Issue 2 2005
    Ann Meyler
    Abstract This study examined visual, auditory, and cross-modal temporal pattern processing at the nonlinguistic and sublexical linguistic levels, and the relationships between these abilities and decoding skill. The central question addressed whether dyslexic readers are impaired in their perception of timing, as assessed by sensitivity to rhythm. Participants were college-level adult dyslexic and normal readers. The dyslexic adults evidenced generalized impairment in temporal processing: they were less accurate and slower than normal readers when required to detect the temporal gap that differentiated pairs of patterns. Impairment was greatest when processing visual syllables. Temporal pattern processing correlated to decoding ability only among normal readers. It is suggested that high-functioning dyslexics may cope with temporal processing problems by adopting a predominantly holistic, orthographic strategy when decoding. It is proposed that there may be cumulative effects of processing demands from different sources including modality, stimulus complexity, and linguistic demands, and that combinations of these may interact to impact temporal processing ability. Moreover, there may be fundamentally distinct and dissociable temporal processing abilities, each of which may be differently linked developmental dyslexia. Copyright © 2005 John Wiley & Sons, Ltd. [source]

    Induced biotic responses to herbivory and associated cues in the Amazonian ant-plant Maieta poeppigii

    Alexander V. Christianini
    Abstract Ants inhabiting ant-plants can respond to cues of herbivory, such as the presence of herbivores, leaf damage, and plant sap, but experimental attempts to quantify the dynamic nature of biotic defenses have been restricted to a few associations between plants and ants. We studied the relationship between certain features of the ant-shrub Maieta poeppigii Cogn. (Melastomataceae) and the presence or absence of ant patrolling on the leaf surface in plants occupied by the ant Pheidole minutula Mayr (Hymenoptera: Formicidae). We also carried out field experiments to examine ant behavior following plant damage, and the potential cues that induce ant recruitment. These experiments included clipping of the leaf apex, as well as the presentation of a potential herbivore (live termite worker) and a foliar extract from Maieta on treatment leaves. The presence of ants patrolling the leaves of M. poeppigii is influenced by the number of domatia on the plant. Ant patrolling on the leaves of M. poeppigii was constant throughout a 24 h cycle, but the mean number of patrolling ants decreased from young to mature leaves, and from leaves with domatia to those without domatia. There was an overall increase in the number of ants on experimental leaves following all treatments, compared to control leaves. Visual and chemical cues associated with herbivory are involved in the induction of ant recruitment in the Maieta,Pheidole system. The continuous patrolling behavior of ants, associated with their ability to respond rapidly to foliar damage, may result in the detection and repellence/capture of most insect herbivores before they can inflict significant damage to the leaves. [source]

    A combination of implicit and adaptative upwind tools for the numerical solution of incompressible free surface flows

    V. G. Ferreira
    Abstract This paper is concerned with the numerical solutions of time dependent two-dimensional incompressible flows. By using the primitive variables of velocity and pressure, the Navier,Stokes and mass conservation equations are solved by a semi-implicit finite difference projection method. A new bounded higher order upwind convection scheme is employed to deal with the non-linear (advective) terms. The procedure is an adaptation of the GENSMAC (J. Comput. Phys. 1994; 110:171,186) methodology for calculating confined and free surface fluid flows at both low and high Reynolds numbers. The calculations were performed by using the 2D version of the Freeflow simulation system (J. Comp. Visual. Science 2000; 2:199,210). In order to demonstrate the capabilities of the numerical method, various test cases are presented. These are the fully developed flow in a channel, the flow over a backward facing step, the die-swell problem, the broken dam flow, and an impinging jet onto a flat plate. The numerical results compare favourably with the experimental data and the analytical solutions. Copyright © 2006 John Wiley & Sons, Ltd. [source]

    Visual working memory of jungle crows (Corvus macrorhynchos) in operant delayed matching-to-sample,

    Abstract We examined the capacity of visual working memory in three male jungle crows using an operant delayed matching-to-sample procedure. In the delayed matching-to-sample, each trial started with the presentation of a sample stimulus, followed by the presentation of comparison stimuli after a delay interval. The choice of the matching comparison was rewarded. Jungle crows showed a steady decline in proportion correct with increasing delay interval. The proportion correct was higher when the sample stimulus was the same in the preceding trial, suggesting that proactive interference prevented the birds from retrieving the memory successfully. The analysis of response time revealed that response time was faster in correct than incorrect trials when the matching performance was acquired. Furthermore, response time linearly increased as the delay interval increased. Response time may reflect the processing of scanning memory as well as the level of confidence in their choice when retrieving. [source]

    The Effect of an Attachment-Based Behaviour Therapy for Children with Visual and Severe Intellectual Disabilities

    P. S. Sterkenburg
    Background, A combination of an attachment-based therapy and behaviour modification was investigated for children with persistent challenging behaviour. Method, Six clients with visual and severe intellectual disabilities, severe challenging behaviour and with a background of pathogenic care were treated. Challenging behaviour was recorded continuously in the residential home and during therapy sessions. Alternating treatments were given by two therapists. In phase 1, the experimental therapist attempted to build an attachment relationship in sessions alternating with sessions in which a control therapist provided positive attention only. In phase 2, both therapists applied the same behaviour modification protocol. Results, Across clients, challenging behaviour in the residential home decreased during the attachment therapy phase. The behaviour modification sessions conducted by the experimental therapist resulted in significantly more adaptive target behaviour than the sessions with the control therapist. Conclusion, For these clients with a background of attachment problems, attachment-based behaviour modification treatment may have important advantages over standard behaviour modification. [source]

    Fusing Visual and Inertial Sensing to Recover Robot Ego-motion

    Guillem Alenyà
    A method for estimating mobile robot ego-motion is presented, which relies on tracking contours in real-time images acquired with a calibrated monocular video system. After fitting an active contour to an object in the image, 3D motion is derived from the affine deformations suffered by the contour in an image sequence. More than one object can be tracked at the same time, yielding some different pose estimations. Then, improvements in pose determination are achieved by fusing all these different estimations. Inertial information is used to obtain better estimates, as it introduces in the tracking algorithm a measure of the real velocity. Inertial information is also used to eliminate some ambiguities arising from the use of a monocular image sequence. As the algorithms developed are intended to be used in real-time control systems, considerations on computation costs are taken into account. © 2004 Wiley Periodicals, Inc. [source]

    Obstacles in large-scale epidemiological assessment of sensory impairments in a Dutch population with intellectual disabilities

    H. Evenhuis
    Abstract Background A population-based epidemiological study on visual and hearing impairment was planned in a random sample of 2100 clients, drawn from a base population of 9012 users of Dutch residential and day-care intellectual disability (ID) services with the whole range of IDs. Stratification was applied for age 50 years and over and Down syndrome. Visual and hearing functions were assessed according to a standardized protocol, in cooperation with regular ophthalmologists and regional audiological centres. Anticipated obstacles in sample collection, random inclusion, informed consent, expertise of investigators, time and costs were eliminated by a careful preparation. However, inclusion and participation were incomplete. Method In a descriptive retrospective design, we collected data from our study files on inclusion and participation as well as reasons for non-participation, to identify unanticipated obstacles for this kind of research. Results Consent was obtained for 1660 clients, and 1598 clients participated in the data collection (76% of intended sample of 2100). Inclusion and participation rates were especially lower in community-based care organizations, resulting in unintentional skewing of the sample towards more severe levels of ID. Complete and reliable data to diagnose visual impairment were obtained for 1358/1598 (85%) and to diagnose hearing impairment for 1237/1598 participants (77%). Unanticipated obstacles had to do with the quality of coordination within care organizations, with characteristics of screening methods, and with collaboration with the regular health care system. Assessments of visual function were more easy to organize than were those of hearing. Based on our current experience, practical recommendations are given for future multicentre research, especially in community-based settings. [source]

    Binge Drinking Affects Attentional and Visual Working Memory Processing in Young University Students

    ALCOHOLISM, Issue 11 2009
    Alberto Crego
    Background:, Binge Drinking (BD) typically involves heavy drinking over a short time, followed by a period of abstinence, and is common among young people, especially university students. Animal studies have demonstrated that this type of alcohol consumption causes brain damage, especially in the nonmature brain. The aim of the present study was to determine how BD affects brain functioning in male and female university students, during the performance of a visual working memory task. Methods:, Event-related potentials (ERPs) were recorded, with an extensive set of 32 scalp electrodes, in 95 first-year university students (age range 18 to 20 years), comprising 42 binge drinkers (BD) and 53 controls, in a visual "identical pairs" continuous performance task. Principal components analysis was used to identify and analyze the N2 (negative waveform with a latency around 200 to 300 ms related to attentional processes) and P3 (positive waveform with a latency around 300 to 600 ms related to working memory processes) components of the ERPs. Results:, In the matching condition of the task, the N2 component in central and parietal regions was significantly larger in the BD than in the control group. In the control group, the P3 component was larger in the matching than in the nonmatching condition in the frontal, central, and parietal regions, whereas the BD group did not show any significant differences between conditions in any region. Conclusions:, The results of this study confirm the presence of electrophysiological differences between young university student binge drinkers and controls during the execution of a visual task with a high working memory load. The larger N2 in the BD group suggests higher levels of attentional effort required by this group to perform the task adequately. The absence of any differences in the P3 component in the different conditions (matching and nonmatching stimuli) in the BD group suggests a deficiency in the electrophysiological differentiation between relevant and irrelevant information, which may reflect some impairment of working memory processes. [source]

    Probing the origin of the dark material on Iapetus

    F. Tosi
    ABSTRACT Among the icy satellites of Saturn, Iapetus shows a striking dichotomy between its leading and trailing hemispheres, the former being significantly darker than the latter. Thanks to the Visual and Infrared Mapping Spectrometer (VIMS) imaging spectrometer on-board Cassini, it is now possible to investigate the spectral features of the satellites in Saturn system within a wider spectral range and with an enhanced accuracy than with previously available data. In this work, we present an application of the G-mode method to the high resolution, visible and near-infrared data of Phoebe, Iapetus and Hyperion collected by Cassini/VIMS, in order to search for compositional correlations. We also present the results of a dynamical study on the efficiency of Iapetus in capturing dust grains travelling inwards in Saturn system with the aim of evaluating the viability of the Poynting,Robertson drag as the physical mechanism transferring the dark material to the satellite. The results of spectroscopic classification are used jointly with the ones of the dynamical study to describe a plausible physical scenario for the origin of Iapetus' dichotomy. Our work shows that mass transfer from the outer Saturnian system is an efficient mechanism, particularly for the range of sizes hypothesized for the particles composing the newly discovered outer ring around Saturn. Both spectral and dynamical data indicate Phoebe as the main source of the dark material. However, due to considerations on the collisional history of the Saturnian irregular satellites and to the differences in the spectral features of Phoebe and the dark material on Iapetus in the visible and ultraviolet range, we suggest a multisource scenario where now extinct prograde satellites and the disruptive impacts that generated the putative collisional families played a significant role in supplying the original amount of dark material. [source]

    Dopamine transporter single photon emission computerized tomography in the diagnosis of dementia with Lewy bodies,

    FRCP, Rodney W.H. Walker PhD
    Abstract Dementia with Lewy bodies (DLB) is part of the spectrum of Lewy body disorders. However, it may be difficult to diagnose patients who have dementia but no Parkinsonism. Visual and semiquantitative assessment of the nigrostriatal dopaminergic nerve terminals in the putamen and caudate nuclei can be obtained with single photon emission computerized tomography (SPECT) using ligands that bind to the dopamine transporter molecule in the membranes of the nigrostriatal nerve terminals. This can be employed as a means of identifying subclinical degeneration of nigrostriatal neurones in patients with suspected DLB, increasing the probability of the diagnosis. In several studies, the sensitivity and specificity of abnormal dopamine transporter scans with regard to diagnosing probable DLB are better than 75 and 90%, respectively. This communication outlines the evidence for this and discusses some of the advantages, potential disadvantages, and areas of uncertainty with regard to the use of dopamine transporter SPECT in DLB diagnosis. © 2009 Movement Disorder Society [source]

    The clinical spectrum of freezing of gait in Parkinson's disease,

    Yasuyuki Okuma MD
    Abstract Freezing of gait (FOG) is a common and very disabling symptom in Parkinson's disease (PD). It is usually observed in the advanced stage of the disease, although a mild form can be seen in the early stage. Although some studies have suggested that longer duration of dopaminergic treatment is associated with FOG, the disease progression alone may be responsible for the development of FOG. FOG can be experienced on turning, in narrow spaces, while reaching a destination, and in stressful situations. In PD, FOG is strongly associated with motor fluctuation. FOG is commonly observed in the "off" state and is observed less frequently in the "on" state. Dual tasking (cognitive load) aggravates FOG. Visual or auditory cues often resolve FOG. Analysis of gait revealed that the stepping rhythm suddenly jumps into high frequency (4,5 Hz) in FOG (hastening), and that floor reaction forces are disregulated. Since the hastening phenomenon was also reported in patients with lesions in the striatum and/or the frontal lobe, fronto-basal ganglia projections are considered essential for FOG. Careful observation and gait pattern analysis may lead to a successful management of individual PD patients with FOG. © 2008 Movement Disorder Society [source]

    Visual and brainstem auditory evoked potentials in children with headache

    Bulent Unay
    Abstract Background: Headache is a common problem in the pediatric population. The purpose of the present study was to evaluate visual evoked potentials (VEP) and brainstem auditory evoked potentials (BAEP) in children with headache. Methods: Thirty-seven children fulfilling the International Headache Society Criteria for a diagnosis of migraine, 35 children with tension-type headache and 40 healthy children (control group) were enrolled in the study. Results: The mean age of patients and controls was 10.4 years. P100 latency and amplitudes of migraine patients were significantly higher than children with tension-type headache and control subjects. Children with tension-type headache also had higher P100 latency and amplitude values than control subjects but there was no statistical difference. BAEP responses were similar between all groups. Conclusion: Measurement of VEP latency and amplitude is a valuable and reliable test for the diagnosis of migraine and can be used safely in childhood. [source]

    Six novel mutations of the ADAR1 gene in patients with dyschromatosis symmetrica hereditaria: Histological observation and comparison of genotypes and clinical phenotypes

    Taisuke KONDO
    ABSTRACT Dyschromatosis symmetrica hereditaria (DSH), is a pigmentary genodermatosis of autosomal dominant inheritance. Since we clarified that the disease is caused by a mutation of the adenosine deaminase acting on the RNA 1 gene (ADAR1) in 2003, the molecular pathogenesis of a peculiar clinical feature of the disease has been expected to be clarified. We examined five familial cases and one sporadic case of Japanese families with DSH. The mutation analyses were done with single-strand conformation polymorphism/heteroduplex (SSCP/HD) analysis and direct sequencing of ADAR1. The DNA analysis of each patient revealed one missense mutation (p.F1091S), two nonsense mutations (p.C893X, p.S581X) and three frame-shift mutations (p.E498fsX517, p.F1091fsX1092, p.L855fsX856). Visual and electron microscopic findings showed abundant melanin pigment deposited all over the basal layer, and enlarged melanocytes with long dendrites located in the pigmented lesions with small or immature melanosomes scattered sparsely in the cytoplasm, but in the adjacent keratinocytes many small melanosomes were singly dispersed or aggregated. The hypopigmented areas showed little melanin deposition and reduced numbers of melanocytes in which much degenerative cytoplasmic vacuole formation could be observed by electron microscopy. Herein, we report six cases of DSH with six novel mutations. The variety of their clinical phenotypes even in the pedigree may suggest the presence of factors other than the ADAR1 gene influencing the extent of the clinical skin lesion. Microscopic findings suggest that the clinical appearance must have developed directly by melanocyte variations mainly induced by the ADAR1 gene mutations. [source]

    Visual and non-visual control of landing movements in humans

    Marco Santello
    1The role of vision in controlling leg muscle activation in landing from a drop was investigated. Subjects (n= 8) performed 10 drops from four heights (0.2, 0.4, 0.6 and 0.8 m) with and without vision. Drop height was maintained constant throughout each block of trials to allow adaptation. The aim of the study was to assess the extent to which proprioceptive and vestibular information could substitute for the lack of vision in adapting landing movements to different heights. 2At the final stages of the movement, subjects experienced similar peak centre of body mass (CM) displacements and joint rotations, regardless of the availability of vision. This implies that subjects were able to adapt the control of landing to different heights. The amplitude and timing of electromyographic signals from the leg muscles scaled to drop height in a similar fashion with and without vision. 3However, variables measured throughout the execution of the movement indicated important differences. Without vision, landings were characterised by 10 % larger ground reaction forces, 10 % smaller knee joint rotations, different time lags between peak joint rotations, and more variable ground reaction forces and times to peak CM displacement. 4We conclude that non-visual sensory information (a) could not fully compensate for the lack of continuous visual feedback and (b) this non-visual information was used to reorganise the motor output. These results suggest that vision is important for the very accurate timing of muscle activity onset and the kinematics of landing. [source]

    Computer aided self-monitoring to increase academic production and reduce self-injurious behavior in a child with autism

    Denise A. Soares
    Self-monitoring to increase the on-task behavior of students with learning disabilities has been the focus of numerous studies in the literature. This study examined the effectiveness of computer aided self-monitoring of academic task completion to reduce self-injurious behavior in a 13-year-old male student with autism. Using an ABAB design, data were collected over 22 sessions in a resource-reading classroom. Visual and statistical analyses indicated that when self-monitoring of activity completion was implemented, rates of completion increased and maladaptive behaviors such as self-injurious behavior and tantruming decreased. Discussion follows for implications for self-monitoring with students with autism. Copyright © 2009 John Wiley & Sons, Ltd. [source]

    Signaling stimulus presentation during treatment with noncontingent reinforcement: Visual versus vocal signals

    John J. Schadler Jr.
    The independent effects of two signals implemented during treatment with noncontingent reinforcement (NCR) were examined. First, functional analyses showed that problem behavior exhibited by two individuals with developmental disabilities was sensitive to social positive reinforcement. A reversal design was then used to compare the effectiveness of a timer (NCR-visual) to a vocal statement (NCR-vocal) indicating when the stimulus would be returned in the context of a NCR procedure. Results showed that NCR reduced problem behavior for both participants. In addition, for one participant, the NCR-visual condition reduced problem behavior to a greater degree than the NCR-vocal condition. Copyright © 2009 John Wiley & Sons, Ltd. [source]

    Usefulness of translesional pressure gradient and pharmacological provocation for the assessment of intermediate renal artery disease

    Noah J. Jones MD
    Abstract Objective: We sought to determine the hemodynamic significance of intermediate RAS by measuring translesional systolic pressure gradients (TSPG), using a pressure-sensing guidewire at baseline and after acetylcholine (ACh) induced hyperemia, following selective renal artery angiography. Background: Renal artery stenosis (RAS) is a cause of reversible hypertension and nephropathy. Stenting effectively relieves RAS, however improvement in blood pressure control or renal function is variable and unpredictable. Hemodynamic significance is usually present with RAS when diameter stenosis is >75%, but is less predictable in intermediate (30%,75%) RAS. Methods: Twenty-two patients (26 renal arteries) with uncontrolled hypertension underwent invasive hemodynamic assessment because of intermediate RAS, defined as radiocontrast angiographic diameter stenosis (DS) between 30% and 75% (quantitative DS was measured prospectively). Translesional pressure gradients were measured using a 0.014" pressure-sensing wire. Hyperemia was induced by administration of intrarenal ACh. Results: Visual and measured angiographic lesion severity did not correlate with TSPG either at baseline (visual DS, R2 = 0.091, P = 0.13; measured DS, R2 = 0.124, P = 0.07) or with hyperemia (visual DS, R2 = 0.057, P = 0.24; measured DS, R2 = 0.101, P = 0.12). Baseline and maximal hyperemic gradient did correlate (R2 = 0.567; P < 0.05). Pharmacological provocation produced a significant increase in TSPG (mean; baseline, 18 ± 21 vs. hyperemia, 34 ± 41 mm Hg; P < 0.05). A hemodynamically significant lesion (TSPG > 20 mm Hg) was found in 14/26 (54%) arteries (13 patients); 13 (60%) patients subsequently underwent renal artery stenting for hemodynamically significant RAS. At follow-up (at least 30 days), there was a significant decrease in systolic blood pressure (mean; 167 ± 24 vs. 134 ± 19 mm Hg; P < 0.001). Conclusions: Intrarenal administration of ACh induces hyperemia and can be used to unmask resistive renal artery lesions. Gradient measurement and induced hyperemia may be warranted in the invasive assessment of intermediate renal artery stenoses, rather than relying on stenosis severity alone. Further study is needed to determine whether translesional pressure gradients and pharmacological provocation predict clinical benefit after renal artery stenting. © 2006 Wiley-Liss, Inc. [source]

    Stochasticity of Manganese Superoxide Dismutase mRNA Expression in Breast Carcinoma Cells by Molecular Beacon Imaging

    CHEMBIOCHEM, Issue 11 2005
    Timothy J. Drake
    Abstract Visual and quantitative monitoring of cell-to-cell variation in the expression of manganese superoxide dismutase (MnSOD) mRNA by using novel ratiometric imaging with molecular beacons (MB) reveals a distinct change in patterns following induction of human breast-carcinoma cells with lipopolysaccharide. Interestingly, the pattern of cell-to-cell variation in a cell line stably transfected with a plasmid bearing a cDNA clone of MnSOD and overproducing the enzyme is significantly different from the pattern associated with MnSOD induction. The levels and the patterns of cell-population heterogeneity for ,-actin mRNA expression do not show distinct changes either following induction or in stably transfected cells. These results are significant in light of the reported relationship between this enzyme and malignant phenotype of breast-carcinoma cells. Use of MBs in ratiometric image analyses for cytoplasmic mRNAs represents a novel means of directly examining the stochasticity of transcription of MnSOD and other genes implicated in cellular phenotype regulation. [source]

    Developmental Differences in Visual and Auditory Processing of Complex Sentences

    CHILD DEVELOPMENT, Issue 4 2000
    James R. Booth
    Children aged 8 through 11 (N= 250) were given a word-by-word sentence task in both the visual and auditory modes. The sentences included an object relative clause, a subject relative clause, or a conjoined verb phrase. Each sentence was followed by a true,false question, testing the subject of either the first or second verb. Participants were also given two memory span measures: digit span and reading span. High digit span children slowed down more at the transition from the main to the relative clause than did the low digit span children. The findings suggest the presence of a U-shaped learning pattern for on-line processing of restrictive relative clauses. Off-line accuracy scores showed different patterns for good comprehenders and poor comprehenders. Poor comprehenders answered the second verb questions at levels that were consistently below chance. Their answers were based on an incorrect local attachment strategy that treated the second noun as the subject of the second verb. For example, they often answered yes to the question ,The girl chases the policeman' after the object relative sentence ,The boy that the girl sees chases the policeman.' Interestingly, low memory span poor comprehenders used the local attachment strategy less consistently than high memory span poor comprehenders, and all poor comprehenders used this strategy less consistently for harder than for easier sentences. [source]

    Fast display of large-scale forest with fidelity

    Huaisheng Zhang
    Abstract We propose a new hierarchical representation for a forest model, namely hierarchical layered depth mosaics (HLDM). Each node in the HLDM comprises a number of discrete textured quadrilaterals, called depth mosaics (DMs). The DMs are generated from the sampled depth images of the polygonal tree models. Meanwhile, their textures are compressed by a new approach accounting for occlusion. Our rendering procedure traverses the HLDM and renders the appropriate nodes according to a view-dependent selection criterion. A blending scheme is adopted to mitigate the visual ,popping' caused by the transition of levels of detail. The experiment demonstrates that the viewer could interactively walk or fly above the forest with fidelity. Copyright © 2006 John Wiley & Sons, Ltd. [source]

    Planetary gear set and automatic transmission simulation for machine design courses,

    Scott T. Dennis
    Abstract Due to their unique ability to provide a variety of gear ratios in a very compact space, planetary gear systems are seen in many applications from small powered screw drivers to automobile automatic transmissions. The versatile planetary gear device is often studied as part of an undergraduate mechanical engineering program. Textbook presentations typically illustrate how the different planetary gear components are connected. Understanding of the operation of the planetary gear set can be enhanced using actual hardware or simulations that show how the components move relative to each other. The Department of Engineering Mechanics at the United States Air Force Academy has developed a computer simulation of the planetary gear set and the Chrysler 42LE automatic transmission. Called "PG-Sim," the dynamic simulations complement a static textbook presentation. PG-Sim is used in several of our courses and assessment data clearly indicates students' appreciation of its visual and interactive features. In this paper, we present an overview of PG-Sim and then describe how the simulation courseware facilitates understanding of the planetary gear system. © 2003 Wiley Periodicals, Inc. Comput Appl Eng Educ 11: 144,155, 2003; Published online in Wiley InterScience (; DOI 10.1002/cae.10045 [source]

    Documenting Loss of Large Trophy Fish from the Florida Keys with Historical Photographs

    arrecifes de coral; ecología histórica; directrices cambiantes; peces de arrecife; sobrepesca Abstract:,A loss of large vertebrates has occurred in aquatic and terrestrial ecosystems, but data to measure long-term population changes are sparse. Historical photographs provide visual and quantitative evidence of changes in mean individual size and species composition for groups of marine fish that have been targeted by sport fishing. I measured such trends for 13 groups of recreationally caught "trophy" reef fish with photographs taken in Key West, Florida, from 1956 to 2007. The mean fish size declined from an estimated 19.9 kg (SE 1.5) to 2.3 kg (SE 0.3), and there was a major shift in species composition. Landings from 1956 to 1960 were dominated by large groupers (Epinephelus spp.), and other large predatory fish were commonly caught, including sharks with an average length of just <2 m. In contrast, landings in 2007 were composed of small snappers (Lutjanus spp. and Ocyurus chrysurus) with an average length of 34.4 cm (SE 0.62), and the average length of sharks declined by more than 50% over 50 years. Major declines in the size of fish caught were not reflected in the price of fishing trips, so customers paid the same amount for a less-valuable product. Historical photographs provide a window into a more pristine coral reef ecosystem that existed a half a century ago and lend support to current observations that unfished reef communities are able to support large numbers of large-bodied fish. Resumen:,Una pérdida de vertebrados mayores ha ocurrido en ecosistemas acuáticos y terrestres, pero los datos para medir los cambios poblaciones a largo plazo son escasos. Las fotografías históricas proporcionan evidencia visual y cuantitativa de cambios en el tamaño individual promedio y de la composición de especies en grupos de peces marinos que han sido blanco de la pesca deportiva. Medí esas tendencias en 13 grupos de peces de arrecife capturados recreativamente como "trofeos" mediante fotografías tomadas en Key West, Florida, desde 1956 a 2007. El peso promedio de los peces declinó de unos 19.9 kg (ES 1.5) a 2.3 kg (ES 0.3), y hubo un cambio mayor en la composición de especies. Las capturas entre 1956 y 1960 estuvieron dominadas por meros (Epinephelus spp.) grandes, y otros peces depredadores eran capturados comúnmente, incluyendo tiburones con una longitud promedio de poco menos de 2m. En contraste, las capturas en 2007 fueron compuestas de pargos (Lutjanus spp. y Ocyurus chrysurus) pequeños con una longitud promedio de 34.4 cm (ES 0.62), y la longitud promedio de los tiburones declinó más de 50% en 50 años. La gran declinación en el tamaño de los peces capturados no se reflejó en los precios de los viajes de pesca, así que los clientes pagaron la misma cantidad por un producto menos valioso. Las fotografías históricas proporcionan una visión de un ecosistema arrecifal coralino prístino que existió hace medio siglo y proporcionan soporte a los comentarios actuales de que las comunidades arrecifales no explotadas son capaces de soportar numerosos peces de talla grande. [source]


    ABSTRACT This article argues for the importance of rewriting the conventional atrocity narrative about violence in King Leopold's Congo Free State in relation to the present, the ongoing war-related humanitarianism and sexual violence in the DRC. The central idea is to push beyond the shock and tenacity of the visual, the ubiquitous mutilation photographs that tend to blot out all else; and instead seek weaker, more fragile acoustic traces in a diverse archive with Congolese words and sounds. This sensory, nonspectral mode of parsing the archive tells us something new about the immediacy of violence, its duration in memory, and the bodily and reproductive effects of sexually torturing women. The sound of twisted laughter convulsed around forms of sexual violence that were constitutive of reproductive ruination during the rubber regime in Leopold's Congo. The work of strategically tethering the past to the present should not be about forging historicist links across time but about locating repetitions and difference, including differences among humanitarian modes and strategies in the early 20th and the early 21st centuries. [source]

    Exploring Whiteness and Multicultural Education with Prospective Teachers

    CURRICULUM INQUIRY, Issue 1 2002
    Alice McIntyre
    In this article, I describe how I initiate an examination of whiteness with predominantly white students in teacher preparation programs by the use of group collages,a pedagogical tool that combines visual, textual, and oral representations of subject matter. In doing so, I illustrate one of the ways teacher educators can provide students with opportunities to (1) "see" whiteness as an integral aspect of educational discourse, (2) fix their gaze on themselves as a collective racial group, and (3) engage in processes aimed at changing beliefs, stereotypes, and practices that reproduce social and educational injustice. [source]

    The Determinants of Students' Perceived Learning Outcomes and Satisfaction in University Online Education: An Empirical Investigation,

    Sean B. Eom
    ABSTRACT In this study, structural equation modeling is applied to examine the determinants of students' satisfaction and their perceived learning outcomes in the context of university online courses. Independent variables included in the study are course structure, instructor feedback, self-motivation, learning style, interaction, and instructor facilitation as potential determinants of online learning. A total of 397 valid unduplicated responses from students who have completed at least one online course at a university in the Midwest were used to examine the structural model. The results indicated that all of the antecedent variables significantly affect students' satisfaction. Of the six antecedent variables hypothesized to affect the perceived learning outcomes, only instructor feedback and learning style are significant. The structural model results also reveal that user satisfaction is a significant predictor of learning outcomes. The findings suggest online education can be a superior mode of instruction if it is targeted to learners with specific learning styles (visual and read/write learning styles) and with timely, meaningful instructor feedback of various types. [source]

    Traumatised permanent teeth in 11,16-year-old Saudi Arabian children with a sensory impairment attending special schools

    M. AlSarheed
    Abstract ,,,The aim of this study was to determine the prevalence of traumatised permanent teeth among sensory (visual (VI) and hearing (HI)) impaired children attending special schools in Riyadh, Saudi Arabia. All the dental injuries involved incisor teeth, and trauma was noted in 33 (6.7%) children attending government schools (control group) compared to 7 (9%) VI children and 24 (11.4%) HI children. Differences in the dental trauma only reached statistical significance between the HI and control group (P < 0.05). Gender differences were only apparent in the HI group, with males having higher levels of traumatised teeth. In addition, HI children aged 11,12 years were more prone to trauma than children in the control group of the same age (P < 0.05). In conclusion, sensory impaired children do have a tendency for more dental trauma. However, this was only statistically significant for HI children. Whereas a gender difference was most noticeable for the HI group, with males having higher levels of trauma, this was noticeable by its absence among VI children. [source]

    Memory deficits in children with and at risk for anxiety disorders

    Roma A. Vasa M.D.
    Abstract There are limited data on the neurocognitive correlates of childhood anxiety disorders. The objective of this study was to examine whether visual and verbal memory deficits of nonemotional stimuli are (1) a shared feature of three common childhood anxiety disorders (social phobia, separation anxiety disorder, and generalized anxiety disorder) or whether these deficits are restricted to specific anxiety disorders, and (2) present in offspring who possess at least one of the following established risk factors for anxiety disorders, parental history of panic disorder (PD), or major depressive disorder (MDD). One hundred and sixty offspring, ages 9,20 years, were recruited from parents with lifetime diagnoses of PD, MDD, PD plus MDD, or neither illness. Different clinicians blindly administered semistructured diagnostic interviews to offspring and parents. Verbal and visual memory subtests of the Wide Range Assessment of Memory and Learning were administered to offspring. The results showed that offspring with ongoing social phobia demonstrated reduced visual but not verbal memory scores compared to those without social phobia when controlling for offspring IQ, separation anxiety disorder, and generalized anxiety disorder. No other offspring anxiety disorder predicted memory performance. Neither parental PD nor parental MDD was associated with offspring memory performance. These findings are relevant to understanding the phenomenology of childhood anxiety disorders and may provide insights into the neural circuits underlying these disorders. Depression and Anxiety 24:85,94, 2007. Published 2006 Wiley-Liss, Inc. [source]