WorldWideScience

Sample records for short-latency disparity vergence

  1. A Pilot Study of Disparity Vergence and Near Dissociated Phoria in Convergence Insufficiency Patients Before versus After Vergence Therapy

    Directory of Open Access Journals (Sweden)

    Tara L. Alvarez

    2015-07-01

    Full Text Available PURPOSE: This study examined the relationship between the near dissociated phoria and disparity vergence eye movements. Convergence insufficiency (CI patients before vergence therapy were compared to: 1 the same patients after vergence therapy and 2 binocularly normal controls (BNC. METHODS: Sixteen subjects were studied--twelve BNC and four with CI. Measurements from the CI subjects were obtained before and after 18 hours of vergence eye movement therapy. The near dissociated phoria was measured using the flashed Maddox rod technique. Vergence responses were stimulated from 4° symmetrical disparity vergence step stimuli. The peak velocity of the vergence response and the magnitude of the fusion initiating component (FIC from an independent component analysis were calculated. A linear regression analysis was conducted studying the vergence peak velocity as a function of the near dissociated phoria where the Pearson correlation coefficient was computed. RESULTS: Before vergence therapy, the average with one standard deviation FIC magnitude of convergence responses from CI subjects was 0.290.82 and significantly less than the FIC magnitude of 1.850.84 for BNC (p<0.02. A paired t-test reported that the FIC and near dissociated phoria before vergence therapy for CI subjects significantly increased to 1.490.57 (p<0.04 and became less exophoric to 3.5∆1.9 exo (p<0.02 after vergence therapy. A significant correlation (r=0.87; p<0.01 was observed between the near dissociated phoria and the vergence ratio of convergence peak velocity divided by divergence peak velocity. CONCLUSION: The results have clinical translational impact in understanding the mechanism by which vergence therapy may be changing the vergence system leading to a sustained reduction in visual symptoms.

  2. Vergence driven accommodation with simulated disparity in myopia and emmetropia.

    Science.gov (United States)

    Maiello, Guido; Kerber, Kristen L; Thorn, Frank; Bex, Peter J; Vera-Diaz, Fuensanta A

    2018-01-01

    The formation of focused and corresponding foveal images requires a close synergy between the accommodation and vergence systems. This linkage is usually decoupled in virtual reality systems and may be dysfunctional in people who are at risk of developing myopia. We study how refractive error affects vergence-accommodation interactions in stereoscopic displays. Vergence and accommodative responses were measured in 21 young healthy adults (n=9 myopes, 22-31 years) while subjects viewed naturalistic stimuli on a 3D display. In Step 1, vergence was driven behind the monitor using a blurred, non-accommodative, uncrossed disparity target. In Step 2, vergence and accommodation were driven back to the monitor plane using naturalistic images that contained structured depth and focus information from size, blur and/or disparity. In Step 1, both refractive groups converged towards the stereoscopic target depth plane, but the vergence-driven accommodative change was smaller in emmetropes than in myopes (F 1,19 =5.13, p=0.036). In Step 2, there was little effect of peripheral depth cues on accommodation or vergence in either refractive group. However, vergence responses were significantly slower (F 1,19 =4.55, p=0.046) and accommodation variability was higher (F 1,19 =12.9, p=0.0019) in myopes. Vergence and accommodation responses are disrupted in virtual reality displays in both refractive groups. Accommodation responses are less stable in myopes, perhaps due to a lower sensitivity to dioptric blur. Such inaccuracies of accommodation may cause long-term blur on the retina, which has been associated with a failure of emmetropization. Copyright © 2017 Elsevier Ltd. All rights reserved.

  3. Vector disparity sensor with vergence control for active vision systems.

    Science.gov (United States)

    Barranco, Francisco; Diaz, Javier; Gibaldi, Agostino; Sabatini, Silvio P; Ros, Eduardo

    2012-01-01

    This paper presents an architecture for computing vector disparity for active vision systems as used on robotics applications. The control of the vergence angle of a binocular system allows us to efficiently explore dynamic environments, but requires a generalization of the disparity computation with respect to a static camera setup, where the disparity is strictly 1-D after the image rectification. The interaction between vision and motor control allows us to develop an active sensor that achieves high accuracy of the disparity computation around the fixation point, and fast reaction time for the vergence control. In this contribution, we address the development of a real-time architecture for vector disparity computation using an FPGA device. We implement the disparity unit and the control module for vergence, version, and tilt to determine the fixation point. In addition, two on-chip different alternatives for the vector disparity engines are discussed based on the luminance (gradient-based) and phase information of the binocular images. The multiscale versions of these engines are able to estimate the vector disparity up to 32 fps on VGA resolution images with very good accuracy as shown using benchmark sequences with known ground-truth. The performances in terms of frame-rate, resource utilization, and accuracy of the presented approaches are discussed. On the basis of these results, our study indicates that the gradient-based approach leads to the best trade-off choice for the integration with the active vision system.

  4. Influence of gap and overlap paradigms on saccade latencies and vergence eye movements in seven-year-old children.

    Science.gov (United States)

    Bucci, Maria Pia; Pouvreau, Nathalie; Yang, Qing; Kapoula, Zoï

    2005-07-01

    The latency of eye movements is influenced by the fixation task; when the fixation stimulus is switched off before the target presentation (gap paradigm) the latency becomes short and express movements occur. In contrast, when the fixation stimulus remains on when the target appears (overlap paradigm), eye movement latency is longer. Several previous studies have shown increased rates of express saccades in children; however the presence of an express type of latency for vergence and combined movements in children has never been explored. The present study examines the effects of the gap and the overlap paradigms on horizontal saccades at far (150 cm) and at close (20 cm) viewing distances, on vergence along the median plane, and on saccades combined with convergence or divergence in 15 normal seven-year-old children. The results show that the gap paradigm produced shorter latency for all eye movements than the overlap paradigm, but the difference was only significant for saccades at close viewing distances, for divergence (pure and combined), and for saccades combined with vergence. The gap paradigm produced significantly higher rates of express latencies for saccades at close viewing distances, for divergence, and for saccades combined with divergence; in contrast, the frequencies of express latencies for saccades at far viewing distances and for convergence (pure or combined) were similar in the gap and the overlap paradigms. Interestingly, the rate of anticipatory latencies (gap paradigm. Our collective findings suggest that the initiation of saccades at close viewing distances and of divergence is more reflexive, particularly in the gap paradigm. The finding of frequent anticipatory divergence that occurs at similar rates for seven-year-old children (this study) and for adults (Coubard et al., 2004, Exp Brain Res 154:368-381) indicates that predictive initiation of divergence is dominant.

  5. The stimulus integration area for horizontal vergence.

    Science.gov (United States)

    Allison, Robert S; Howard, Ian P; Fang, Xueping

    2004-06-01

    Over what region of space are horizontal disparities integrated to form the stimulus for vergence? The vergence system might be expected to respond to disparities within a small area of interest to bring them into the range of precise stereoscopic processing. However, the literature suggests that disparities are integrated over a fairly large parafoveal area. We report the results of six experiments designed to explore the spatial characteristics of the stimulus for vergence. Binocular eye movements were recorded using magnetic search coils. Each dichoptic display consisted of a central target stimulus that the subject attempted to fuse, and a competing stimulus with conflicting disparity. In some conditions the target was stationary, providing a fixation stimulus. In other conditions, the disparity of the target changed to provide a vergence-tracking stimulus. The target and competing stimulus were combined in a variety of conditions including those in which (1) a transparent textured-disc target was superimposed on a competing textured background, (2) a textured-disc target filled the centre of a competing annular background, and (3) a small target was presented within the centre of a competing annular background of various inner diameters. In some conditions the target and competing stimulus were separated in stereoscopic depth. The results are consistent with a disparity integration area with a diameter of about 5 degrees. Stimuli beyond this integration area can drive vergence in their own right, but they do not appear to be summed or averaged with a central stimulus to form a combined disparity signal. A competing stimulus had less effect on vergence when separated from the target by a disparity pedestal. As a result, we propose that it may be more useful to think in terms of an integration volume for vergence rather than a two-dimensional retinal integration area.

  6. Saccades and Vergence Performance in a Population of Children with Vertigo and Clinically Assessed Abnormal Vergence Capabilities

    Science.gov (United States)

    Bucci, Maria Pia; Kapoula, Zoï; Bui-Quoc, Emmanuel; Bouet, Aurelie; Wiener-Vacher, Sylvette

    2011-01-01

    Purpose Early studies reported some abnormalities in saccade and vergence eye movements in children with vertigo and vergence deficiencies. The purpose of this study was to further examine saccade and vergence performance in a population of 44 children (mean age: 12.3±1.6 years) with vertigo symptoms and with different levels of vergence abnormalities, as assessed by static orthoptic examination (near point of convergence, prism bar and cover-uncover test). Methods Three groups were identified on the basis of the orthoptic tests: group 1 (n = 13) with vergence spasms and mildly perturbed orthoptic scores, group 2 (n = 14) with moderately perturbed orthoptic scores, and group 3 (n = 17) with severely perturbed orthoptic scores. Data were compared to those recorded from 28 healthy children of similar ages. Latency, accuracy and peak velocity of saccades and vergence movements were measured in two different conditions: gap (fixation offset 200 ms prior to target onset) and simultaneous paradigms. Binocular horizontal movements were recorded by a photoelectric device. Results Group 2 of children with vergence abnormalities showed significantly longer latency than normal children in several types of eye movements recorded. For all three groups of children with vergence abnormalities, the gain was poor, particularly for vergence movement. The peak velocity values did not differ between the different groups of children examined. Interpretation Eye movement measures together with static orthoptic evaluation allowed us to better identify children with vergence abnormalities based on their slow initiation of eye movements. Overall, these findings support the hypothesis of a central deficit in the programming and triggering of saccades and vergence in these children. PMID:21858007

  7. Saccades and vergence performance in a population of children with vertigo and clinically assessed abnormal vergence capabilities.

    Directory of Open Access Journals (Sweden)

    Maria Pia Bucci

    Full Text Available PURPOSE: Early studies reported some abnormalities in saccade and vergence eye movements in children with vertigo and vergence deficiencies. The purpose of this study was to further examine saccade and vergence performance in a population of 44 children (mean age: 12.3±1.6 years with vertigo symptoms and with different levels of vergence abnormalities, as assessed by static orthoptic examination (near point of convergence, prism bar and cover-uncover test. METHODS: Three groups were identified on the basis of the orthoptic tests: group 1 (n = 13 with vergence spasms and mildly perturbed orthoptic scores, group 2 (n = 14 with moderately perturbed orthoptic scores, and group 3 (n = 17 with severely perturbed orthoptic scores. Data were compared to those recorded from 28 healthy children of similar ages. Latency, accuracy and peak velocity of saccades and vergence movements were measured in two different conditions: gap (fixation offset 200 ms prior to target onset and simultaneous paradigms. Binocular horizontal movements were recorded by a photoelectric device. RESULTS: Group 2 of children with vergence abnormalities showed significantly longer latency than normal children in several types of eye movements recorded. For all three groups of children with vergence abnormalities, the gain was poor, particularly for vergence movement. The peak velocity values did not differ between the different groups of children examined. INTERPRETATION: Eye movement measures together with static orthoptic evaluation allowed us to better identify children with vergence abnormalities based on their slow initiation of eye movements. Overall, these findings support the hypothesis of a central deficit in the programming and triggering of saccades and vergence in these children.

  8. Central crosstalk for somatic tinnitus: abnormal vergence eye movements.

    Directory of Open Access Journals (Sweden)

    Qing Yang

    Full Text Available BACKGROUND: Frequent oulomotricity problems with orthoptic testing were reported in patients with tinnitus. This study examines with objective recordings vergence eye movements in patients with somatic tinnitus patients with ability to modify their subjective tinnitus percept by various movements, such as jaw, neck, eye movements or skin pressure. METHODS: Vergence eye movements were recorded with the Eyelink II video system in 15 (23-63 years control adults and 19 (36-62 years subjects with somatic tinnitus. FINDINGS: 1 Accuracy of divergence but not of convergence was lower in subjects with somatic tinnitus than in control subjects. 2 Vergence duration was longer and peak velocity was lower in subjects with somatic tinnitus than in control subjects. 3 The number of embedded saccades and the amplitude of saccades coinciding with the peak velocity of vergence were higher for tinnitus subjects. Yet, saccades did not increase peak velocity of vergence for tinnitus subjects, but they did so for controls. 4 In contrast, there was no significant difference of vergence latency between these two groups. INTERPRETATION: The results suggest dysfunction of vergence areas involving cortical-brainstem-cerebellar circuits. We hypothesize that central auditory dysfunction related to tinnitus percept could trigger mild cerebellar-brainstem dysfunction or that tinnitus and vergence dysfunction could both be manifestations of mild cortical-brainstem-cerebellar syndrome reflecting abnormal cross-modality interactions between vergence eye movements and auditory signals.

  9. A novel experimental method for measuring vergence and accommodation responses to the main near visual cues in typical and atypical groups.

    Science.gov (United States)

    Horwood, Anna M; Riddell, Patricia M

    2009-01-01

    Binocular disparity, blur, and proximal cues drive convergence and accommodation. Disparity is considered to be the main vergence cue and blur the main accommodation cue. We have developed a remote haploscopic photorefractor to measure simultaneous vergence and accommodation objectively in a wide range of participants of all ages while fixating targets at between 0.3 and 2 m. By separating the three main near cues, we can explore their relative weighting in three-, two-, one-, and zero-cue conditions. Disparity can be manipulated by remote occlusion; blur cues manipulated by using either a Gabor patch or a detailed picture target; looming cues by either scaling or not scaling target size with distance. In normal orthophoric, emmetropic, symptom-free, naive visually mature participants, disparity was by far the most significant cue to both vergence and accommodation. Accommodation responses dropped dramatically if disparity was not available. Blur only had a clinically significant effect when disparity was absent. Proximity had very little effect. There was considerable interparticipant variation. We predict that relative weighting of near cue use is likely to vary between clinical groups and present some individual cases as examples. We are using this naturalistic tool to research strabismus, vergence and accommodation development, and emmetropization.

  10. The interactive processes of accommodation and vergence.

    Science.gov (United States)

    Semmlow, J L; Bérard, P V; Vercher, J L; Putteman, A; Gauthier, G M

    1994-01-01

    A near target generates two different, though related stimuli: image disparity and image blur. Fixation of that near target evokes three motor responses: the so-called oculomotor "near triad". It has long been known that both disparity and blur stimuli are each capable of independently generating all three responses, and a recent theory of near triad control (the Dual Interactive Theory) describes how these stimulus components normally work together in the aid of near vision. However, this theory also indicates that when the system becomes unbalanced, as in high AC/A ratios of some accommodative esotropes, the two components will become antagonistic. In this situation, the interaction between the blur and disparity driven components exaggerates the imbalance created in the vergence motor output. Conversely, there is enhanced restoration when the AC/A ratio is effectively reduced surgically.

  11. Accommodation and vergence response gains to different near cues characterize specific esotropias.

    Science.gov (United States)

    Horwood, Anna M; Riddell, Patricia M

    2013-09-01

    To describe preliminary findings of how the profile of the use of blur, disparity, and proximal cues varies between non-strabismic groups and those with different types of esotropia. This was a case control study. A remote haploscopic photorefractor measured simultaneous convergence and accommodation to a range of targets containing all combinations of binocular disparity, blur, and proximal (looming) cues. Thirteen constant esotropes, 16 fully accommodative esotropes, and 8 convergence excess esotropes were compared with age- and refractive error-matched controls and 27 young adult emmetropic controls. All wore full refractive correction if not emmetropic. Response AC/A and CA/C ratios were also assessed. Cue use differed between the groups. Even esotropes with constant suppression and no binocular vision (BV) responded to disparity in cues. The constant esotropes with weak BV showed trends for more stable responses and better vergence and accommodation than those without any BV. The accommodative esotropes made less use of disparity cues to drive accommodation (p = 0.04) and more use of blur to drive vergence (p = 0.008) than controls. All esotropic groups failed to show the strong bias for better responses to disparity cues found in the controls, with convergence excess esotropes favoring blur cues. AC/A and CA/C ratios existed in an inverse relationship in the different groups. Accommodative lag of > 1.0 D at 33 cm was common (46%) in the pooled esotropia groups compared with 11% in typical children (p = 0.05). Esotropic children use near cues differently from matched non-esotropic children in ways characteristic to their deviations. Relatively higher weighting for blur cues was found in accommodative esotropia compared to matched controls.

  12. Short-term saccadic adaptation in the macaque monkey: a binocular mechanism

    Science.gov (United States)

    Schultz, K. P.

    2013-01-01

    Saccadic eye movements are rapid transfers of gaze between objects of interest. Their duration is too short for the visual system to be able to follow their progress in time. Adaptive mechanisms constantly recalibrate the saccadic responses by detecting how close the landings are to the selected targets. The double-step saccadic paradigm is a common method to simulate alterations in saccadic gain. While the subject is responding to a first target shift, a second shift is introduced in the middle of this movement, which masks it from visual detection. The error in landing introduced by the second shift is interpreted by the brain as an error in the programming of the initial response, with gradual gain changes aimed at compensating the apparent sensorimotor mismatch. A second shift applied dichoptically to only one eye introduces disconjugate landing errors between the two eyes. A monocular adaptive system would independently modify only the gain of the eye exposed to the second shift in order to reestablish binocular alignment. Our results support a binocular mechanism. A version-based saccadic adaptive process detects postsaccadic version errors and generates compensatory conjugate gain alterations. A vergence-based saccadic adaptive process detects postsaccadic disparity errors and generates corrective nonvisual disparity signals that are sent to the vergence system to regain binocularity. This results in striking dynamical similarities between visually driven combined saccade-vergence gaze transfers, where the disparity is given by the visual targets, and the double-step adaptive disconjugate responses, where an adaptive disparity signal is generated internally by the saccadic system. PMID:23076111

  13. Vergence, Vision, and Geometric Optics

    Science.gov (United States)

    Keating, Michael P.

    1975-01-01

    Provides a definition of vergence in terms of the curvature of the wave fronts, and gives examples to illustrate the advantages of this approach. The vergence treatment of geometrical optics provides both conceptual and algebraic advantages, particularly for the life science student, over the traditional object distance-image distance-focal length…

  14. The role of interactions between accommodation and vergence in human visual development

    Science.gov (United States)

    Teel, Danielle F. W.

    Even in early infancy accommodation and vergence interact through neural coupling such that accommodation drives vergence (AC/A ratio) and vergence drives accommodation (CA/C ratio), to assist coordination and development of clear and single binocular vision. Infants have narrow inter-pupillary distances (IPD) requiring less vergence in angular units (degrees or prism diopters), and are typically hyperopic, requiring larger accommodative responses (diopters) than adults. The relative demands also change with emmetropization (decreasing hyperopia) and head growth (increasing IPD) over time. Therefore, adult-like couplings may not be optimal during development and the couplings may play a role in abnormality such as esotropia. A range of cues can drive accommodation and vergence. In addition to blur and disparity, proximity in the form of looming, size and perceived distance has been shown to influence the interactions between accommodation and vergence in adults. The role of this cue in measures of coupling is also poorly understood and may impact key clinical AC/A estimates in young children. Utilizing principles of eccentric photorefraction and Purkinje image eye tracking, this research examines the AC/A and CA/C ratios in infants, preschoolers and adults as a function of age, refractive error and interpupillary distance, plus the role proximity, specifically looming and size cues, plays in estimating the AC/A ratio in three year olds and adults. The AC/A (PD/D) was significantly higher in adults than three-year-olds or infants but similar across age groups in MA/D units. The CA/C was higher in infants than adults or three-year-olds (D/MA and D/PD). Although, not fully reciprocally related, a significant negative relationship was found between the response AC/A and CA/C. Similarly, higher AC/As (PD/D) and lower CA/Cs (D/PD) were associated with larger IPDs and less hyperopia. Although, not statistically significant the absence of proximity resulted in a trend

  15. The effect of water immersion on short-latency somatosensory evoked potentials in human

    Directory of Open Access Journals (Sweden)

    Sato Daisuke

    2012-01-01

    Full Text Available Abstract Background Water immersion therapy is used to treat a variety of cardiovascular, respiratory, and orthopedic conditions. It can also benefit some neurological patients, although little is known about the effects of water immersion on neural activity, including somatosensory processing. To this end, we examined the effect of water immersion on short-latency somatosensory evoked potentials (SEPs elicited by median nerve stimuli. Short-latency SEP recordings were obtained for ten healthy male volunteers at rest in or out of water at 30°C. Recordings were obtained from nine scalp electrodes according to the 10-20 system. The right median nerve at the wrist was electrically stimulated with the stimulus duration of 0.2 ms at 3 Hz. The intensity of the stimulus was fixed at approximately three times the sensory threshold. Results Water immersion significantly reduced the amplitudes of the short-latency SEP components P25 and P45 measured from electrodes over the parietal region and the P45 measured by central region. Conclusions Water immersion reduced short-latency SEP components known to originate in several cortical areas. Attenuation of short-latency SEPs suggests that water immersion influences the cortical processing of somatosensory inputs. Modulation of cortical processing may contribute to the beneficial effects of aquatic therapy. Trial Registration UMIN-CTR (UMIN000006492

  16. Distinct control of initiation and metrics of memory-guided saccades and vergence by the FEF: a TMS study.

    Directory of Open Access Journals (Sweden)

    Qing Yang

    Full Text Available BACKGROUND: The initiation of memory guided saccades is known to be controlled by the frontal eye field (FEF. Recent physiological studies showed the existence of an area close to FEF that controls also vergence initiation and execution. This study is to explore the effect of transcranial magnetic simulation (TMS over FEF on the control of memory-guided saccade-vergence eye movements. METHODOLOGY/PRINCIPAL FINDINGS: Subjects had to make an eye movement in dark towards a target flashed 1 sec earlier (memory delay; the location of the target relative to fixation point was such as to require either a vergence along the median plane, or a saccade, or a saccade with vergence; trials were interleaved. Single pulse TMS was applied on the left or right FEF; it was delivered at 100 ms after the end of memory delay, i.e. extinction of fixation LED that was the "go" signal. Twelve healthy subjects participated in the study. TMS of left or right FEF prolonged the latency of all types of eye movements; the increase varied from 21 to 56 ms and was particularly strong for the divergence movements. This indicates that FEF is involved in the initiation of all types of memory guided movement in the 3D space. TMS of the FEF also altered the accuracy but only for leftward saccades combined with either convergence or divergence; intrasaccadic vergence also increased after TMS of the FEF. CONCLUSIONS/SIGNIFICANCE: The results suggest anisotropy in the quality of space memory and are discussed in the context of other known perceptual motor anisotropies.

  17. Distinct control of initiation and metrics of memory-guided saccades and vergence by the FEF: a TMS study.

    Science.gov (United States)

    Yang, Qing; Kapoula, Zoi

    2011-01-01

    The initiation of memory guided saccades is known to be controlled by the frontal eye field (FEF). Recent physiological studies showed the existence of an area close to FEF that controls also vergence initiation and execution. This study is to explore the effect of transcranial magnetic simulation (TMS) over FEF on the control of memory-guided saccade-vergence eye movements. Subjects had to make an eye movement in dark towards a target flashed 1 sec earlier (memory delay); the location of the target relative to fixation point was such as to require either a vergence along the median plane, or a saccade, or a saccade with vergence; trials were interleaved. Single pulse TMS was applied on the left or right FEF; it was delivered at 100 ms after the end of memory delay, i.e. extinction of fixation LED that was the "go" signal. Twelve healthy subjects participated in the study. TMS of left or right FEF prolonged the latency of all types of eye movements; the increase varied from 21 to 56 ms and was particularly strong for the divergence movements. This indicates that FEF is involved in the initiation of all types of memory guided movement in the 3D space. TMS of the FEF also altered the accuracy but only for leftward saccades combined with either convergence or divergence; intrasaccadic vergence also increased after TMS of the FEF. The results suggest anisotropy in the quality of space memory and are discussed in the context of other known perceptual motor anisotropies.

  18. Short-latency crossed responses in the human biceps femoris muscle

    DEFF Research Database (Denmark)

    Stevenson, Andrew J T; Kamavuako, Ernest N; Geertsen, Svend Sparre

    2015-01-01

    Interlimb reflexes contribute to the central neural coordination between different limbs in both humans and animals. Although commissural interneurons have only been directly identified in animals, spinally mediated interlimb reflexes have been discovered in a number of human lower limb muscles......, indicating their existence in humans. The aim of the present study was to investigate whether short-latency crossed-spinal reflexes are present in the contralateral biceps femoris (cBF) muscle following ipsilateral knee (iKnee) joint rotations during a sitting task, where participants maintained a slight pre...... pathways (likely involving commissural interneurons) from ipsilateral afferents to common motoneurons in the contralateral leg can likely explain the perturbation direction-dependent reversal in the sign of the short-latency cBF reflex. This article is protected by copyright. All rights reserved....

  19. Effect of vergence adaptation on convergence-accommodation: model simulations.

    Science.gov (United States)

    Sreenivasan, Vidhyapriya; Bobier, William R; Irving, Elizabeth L; Lakshminarayanan, Vasudevan

    2009-10-01

    Several theoretical control models depict the adaptation effects observed in the accommodation and vergence mechanisms of the human visual system. Two current quantitative models differ in their approach of defining adaptation and in identifying the effect of controller adaptation on their respective cross-links between the vergence and accommodative systems. Here, we compare the simulation results of these adaptation models with empirical data obtained from emmetropic adults when they performed sustained near task through + 2D lens addition. The results of our experimental study showed an initial increase in exophoria (a divergent open-loop vergence position) and convergence-accommodation (CA) when viewing through +2D lenses. Prolonged fixation through the near addition lenses initiated vergence adaptation, which reduced the lens-induced exophoria and resulted in a concurrent reduction of CA. Both models showed good agreement with empirical measures of vergence adaptation. However, only one model predicted the experimental time course of reduction in CA. The pattern of our empirical results seem to be best described by the adaptation model that indicates the total vergence response to be a sum of two controllers, phasic and tonic, with the output of phasic controller providing input to the cross-link interactions.

  20. Eye vergence responses during a visual memory task.

    Science.gov (United States)

    Solé Puig, Maria; Romeo, August; Cañete Crespillo, Jose; Supèr, Hans

    2017-02-08

    In a previous report it was shown that covertly attending visual stimuli produce small convergence of the eyes, and that visual stimuli can give rise to different modulations of the angle of eye vergence, depending on their power to capture attention. Working memory is highly dependent on attention. Therefore, in this study we assessed vergence responses in a memory task. Participants scanned a set of 8 or 12 images for 10 s, and thereafter were presented with a series of single images. One half were repeat images - that is, they belonged to the initial set - and the other half were novel images. Participants were asked to indicate whether or not the images were included in the initial image set. We observed that eyes converge during scanning the set of images and during the presentation of the single images. The convergence was stronger for remembered images compared with the vergence for nonremembered images. Modulation in pupil size did not correspond to behavioural responses. The correspondence between vergence and coding/retrieval processes of memory strengthen the idea of a role for vergence in attention processing of visual information.

  1. The rate of change of vergence-accommodation conflict affects visual discomfort.

    Science.gov (United States)

    Kim, Joohwan; Kane, David; Banks, Martin S

    2014-12-01

    Stereoscopic (S3D) displays create conflicts between the distance to which the eyes must converge and the distance to which the eyes must accommodate. Such conflicts require the viewer to overcome the normal coupling between vergence and accommodation, and this effort appears to cause viewer discomfort. Vergence-accommodation coupling is driven by the phasic components of the underlying control systems, and those components respond to relatively fast changes in vergence and accommodative stimuli. Given the relationship between phasic changes and vergence-accommodation coupling, we examined how the rate of change in the vergence-accommodation conflict affects viewer discomfort. We used a stereoscopic display that allows independent manipulation of the stimuli to vergence and accommodation. We presented stimuli that simulate natural viewing (i.e., vergence and accommodative stimuli changed together) and stimuli that simulate S3D viewing (i.e., vergence stimulus changes but accommodative stimulus remains fixed). The changes occurred at 0.01, 0.05, or 0.25 Hz. The lowest rate is too slow to stimulate the phasic components while the highest rate is well within the phasic range. The results were consistent with our expectation: somewhat greater discomfort was experienced when stimulus distance changed rapidly, particularly in S3D viewing when the vergence stimulus changed but the accommodative stimulus did not. These results may help in the generation of guidelines for the creation and viewing of stereo content with acceptable viewer comfort.

  2. Interconverting the matrix and principal-meridional representations of dioptric power and reduced vergence.

    Science.gov (United States)

    Harris, W F

    2000-11-01

    Converting the traditional representation of power as sphere, cylinder and axis to the dioptric power matrix F is usually performed by means of Long's equations and the reverse process by means of Keating's equations. It is sometimes useful to be able to convert directly between the matrix and power expressed in terms of principal powers F1 and F2 along corresponding principal meridians at angles a1 and a2. The equations for interconverting F and the principal-meridional representation expressed as F1(a1)F2 are presented here. Equivalent equations allow direct interconversion of the reduced vergence matrix L and the principal-meridional representation of vergence L1(a1)L2. Vergence becomes infinite at line and point focuses. Similarly effective power and back- and front-vertex power are infinite for some systems. Nevertheless it is possible unambiguously to represent infinite vergence and vertex power in principal-meridional form. However, information is usually lost in these infinite cases when the principal-meridional representation is converted to the matrix representation, and the former is not recoverable from the latter. As a consequence the matrix representation is usually unsatisfactory for vergences and vertex powers that are infinite. On the other hand, the principal-meridional representation of vergence and power is always satisfactory. If one adopts the position that effective powers and vertex powers are really vergences rather than powers then one concludes that the matrix provides a satisfactory representation for powers of thin systems in general but not for vergences. Implied by a vergence at a point is an interval of Sturm. The equations for characterizing the interval from the reduced vergence are presented.

  3. DSM-5 Insomnia and Short Sleep: Comorbidity Landscape and Racial Disparities

    Science.gov (United States)

    Kalmbach, David A.; Pillai, Vivek; Arnedt, J. Todd; Drake, Christopher L.

    2016-01-01

    Study Objectives: We estimated rates of cardiometabolic disease, pain conditions, and psychiatric illness associated with Diagnostic and Statistical Manual of Mental Disorders, Fifth Edition (DSM-5) insomnia disorder (current and in remission) and habitual short sleep (fewer than 6 h), and examined the roles of insomnia and short sleep in racial disparities in disease burden between black and non-Hispanic white Americans. Methods: This epidemiological survey study was cross-sectional. The community-based sample consisted of 3,911 subjects (46.0 y ± 13.3; 65.4% female; 25.0% black) across six sleep groups based on DSM-5 insomnia classification (never vs. remitted vs. current) and self-reported habitual sleep duration (normal vs. short). Vascular events, cardiometabolic disease, pain conditions, and psychiatric symptoms were self-reported. Results: Short sleeping insomniacs were at elevated risk for myocardial infarction, stroke, treated hypertension, diabetes, chronic pain, back pain, depression, and anxiety, independent of sex, age, and obesity. Morbidity profiles for insomniacs with normal sleep duration and former insomniacs, irrespective of sleep duration, were similar with elevations in treated hypertension, chronic pain, depression, and anxiety. Regarding racial disparities, cardiometabolic and psychiatric illness burden was greater for blacks, who were more likely to have short sleep and the short sleep insomnia phenotype. Evidence suggested that health disparities may be attributable in part to race-related differences in sleep. Conclusions: Insomnia disorder with short sleep is the most severe phenotype of insomnia and comorbid with many cardiometabolic and psychiatric illnesses, whereas morbidity profiles are highly similar between insomniacs with normal sleep duration and former insomniacs. Short sleep endemic to black Americans increases risk for the short sleep insomnia phenotype and likely contributes to racial disparities in cardiometabolic disease

  4. DSM-5 Insomnia and Short Sleep: Comorbidity Landscape and Racial Disparities.

    Science.gov (United States)

    Kalmbach, David A; Pillai, Vivek; Arnedt, J Todd; Drake, Christopher L

    2016-12-01

    We estimated rates of cardiometabolic disease, pain conditions, and psychiatric illness associated with Diagnostic and Statistical Manual of Mental Disorders, Fifth Edition (DSM-5) insomnia disorder (current and in remission) and habitual short sleep (fewer than 6 h), and examined the roles of insomnia and short sleep in racial disparities in disease burden between black and non-Hispanic white Americans. This epidemiological survey study was cross-sectional. The community-based sample consisted of 3,911 subjects (46.0 y ± 13.3; 65.4% female; 25.0% black) across six sleep groups based on DSM-5 insomnia classification ( never vs. remitted vs. current ) and self-reported habitual sleep duration ( normal vs. short ). Vascular events, cardiometabolic disease, pain conditions, and psychiatric symptoms were self-reported. Short sleeping insomniacs were at elevated risk for myocardial infarction, stroke, treated hypertension, diabetes, chronic pain, back pain, depression, and anxiety, independent of sex, age, and obesity. Morbidity profiles for insomniacs with normal sleep duration and former insomniacs, irrespective of sleep duration, were similar with elevations in treated hypertension, chronic pain, depression, and anxiety. Regarding racial disparities, cardiometabolic and psychiatric illness burden was greater for blacks, who were more likely to have short sleep and the short sleep insomnia phenotype. Evidence suggested that health disparities may be attributable in part to race-related differences in sleep. Insomnia disorder with short sleep is the most severe phenotype of insomnia and comorbid with many cardiometabolic and psychiatric illnesses, whereas morbidity profiles are highly similar between insomniacs with normal sleep duration and former insomniacs. Short sleep endemic to black Americans increases risk for the short sleep insomnia phenotype and likely contributes to racial disparities in cardiometabolic disease and psychiatric illness. © 2016 Associated

  5. Short-term pressure induced suppression of the short-latency response: a new methodology for investigating stretch reflexes

    DEFF Research Database (Denmark)

    Leukel, Christian; Lundbye-Jensen, Jesper; Gruber, Markus

    2009-01-01

    During experiments involving ischemic nerve block, we noticed that the short-latency response (SLR) of evoked stretches in m. soleus decreased immediately following inflation of a pneumatic cuff surrounding the lower leg. The present study aimed to investigate this short-term effect of pressure......) were recorded. Additionally, stretches were applied with different velocities and amplitudes. Finally, the SLR was investigated during hopping and in two protocols that modified the ability of the muscle-tendon complex distal to the cuff to stretch. All measurements were performed with deflated...

  6. Controllable thousand-port low-latency optical packet switch architecture for short link applications

    NARCIS (Netherlands)

    Di Lucente, S.; Nazarathy, J.; Raz, O.; Calabretta, N.; Dorren, H.J.S.; Bienstman, P.; Morthier, G.; Roelkens, G.; et al., xx

    2011-01-01

    The implementation of a low-latency optical packet switch architecture that is controllable while scaling to over thousand ports is investigated in this paper. Optical packet switches with thousand of input/output ports are promising devices to improve the performance of short link applications in

  7. Group Ia afferents likely contribute to short-latency interlimb reflexes in the human biceps femoris muscle

    DEFF Research Database (Denmark)

    Stevenson, Andrew James Thomas; Kamavuako, Ernest Nlandu; Geertsen, Svend Sparre

    2017-01-01

    amplitudes (4 vs. 8°) at the same 150°/s velocity (p’s > 0.08). Conclusion: Because fast conducting group Ia muscle spindle afferents are sensitive to changes in muscle stretch velocity, while group II spindle afferents are sensitive to changes in amplitude (Grey et al., JPhysiol., 2001; Matthews, Trends...... Neurosci., 1991), group Ia velocity sensitive muscle spindle afferents likely contribute to the short-latency crossed spinal reflexes in the cBF muscle following iKnee joint rotations. This supports the findings for the short-latency crossed responses in the human soleus muscle (Stubbs & Mrachacz...... neurons in humans, with primary contributions from group Ia muscle spindle afferents....

  8. Developmental changes in the balance of disparity, blur and looming/proximity cues to drive ocular alignment and focus

    Science.gov (United States)

    Horwood, Anna M; Riddell, Patricia M

    2015-01-01

    Accurate co-ordination of accommodation and convergence is necessary to view near objects and develop fine motor co-ordination. We used a remote haploscopic videorefraction paradigm to measure longitudinal changes in simultaneous ocular accommodation and vergence to targets at different depths, and to all combinations of blur, binocular disparity, and change-in-size (“proximity”) cues. Infants were followed longitudinally and compared to older children and young adults, with the prediction that sensitivity to different cues would change during development. Mean infant responses to the most naturalistic condition were similar to those of adults from 6-7 weeks (accommodation) and 8-9 weeks (vergence). Proximity cues influenced responses most in infants less than 14 weeks of age, but sensitivity declined thereafter. Between 12-28 weeks of age infants were equally responsive to all three cues, while in older children and adults manipulation of disparity resulted in the greatest changes in response. Despite rapid development of visual acuity (thus increasing availability of blur cues), responses to blur were stable throughout development. Our results suggest that during much of infancy, vergence and accommodation responses are not dependent on the development of specific depth cues, but make use of any cues available to drive appropriate changes in response. PMID:24344547

  9. Landward vergence in accretionary prism, evidence for frontal propagation of earthquakes?

    Science.gov (United States)

    cubas, Nadaya; Souloumiac, Pauline

    2016-04-01

    Landward vergence in accretionary wedges is rare and have been described at very few places: along the Cascadia subduction zone and more recently along Sumatra where the 2004 Mw 9.1 Sumatra-Andaman event and the 2011 tsunami earthquake occurred. Recent studies have suggested a relation between landward thrust faults and frontal propagation of earthquakes for the Sumatra subduction zone. The Cascadia subduction zone is also known to have produced in 1700 a Mw9 earthquake with a large tsunami across the Pacific. Based on mechanical analysis, we propose to investigate if specific frictional properties could lead to a landward sequence of thrusting. We show that landward thrust requires very low effective friction along the megathrust with a rather high internal effective friction. We also show that landward thrust appears close to the extensional critical limit. Along Cascadia and Sumatra, we show that to get landward vergence, the effective basal friction has to be lower than 0.08. This very low effective friction is most likely due to high pore pressure. This high pore pressure could either be a long-term property or due to dynamic effects such as thermal pressurization. The fact that landward vergence appears far from the compressional critical limit favors a dynamic effect. Landward vergence would then highlight thermal pressurization due to occasional or systematic propagation of earthquakes to the trench. As a consequence, the vergence of thrusts in accretionary prism could be used to improve seismic and tsunamigenic risk assessment.

  10. A dual visual-local feedback model of the vergence eye movement system

    NARCIS (Netherlands)

    Erkelens, C.J.

    2011-01-01

    Pure vergence movements are the eye movements that we make when we change our binocular fixation between targets differing in distance but not in direction relative to the head. Pure vergence is slow and controlled by visual feedback. Saccades are the rapid eye movements that we make between targets

  11. Geographically Locating an Internet Node Using Network Latency Measurement

    National Research Council Canada - National Science Library

    Turnbaugh, Eugene

    2004-01-01

    .... The difficulties include accurate latency measure, network address translation (NAT) masking, service blocking, disparate physical configuration, dissimilar network hardware, and inaccurate and limited measuring tools...

  12. Reduced vergence adaptation is associated with a prolonged output of convergence accommodation in convergence insufficiency.

    Science.gov (United States)

    Sreenivasan, Vidhyapriya; Bobier, William R

    2014-07-01

    Convergence insufficiency (CI) is a developmental visual anomaly defined clinically by a reduced near point of convergence, a reduced capacity to view through base-out prisms (fusional convergence); coupled with asthenopic symptoms typically blur and diplopia. Experimental studies show reduced vergence parameters and tonic adaptation. Based upon current models of accommodation and vergence, we hypothesize that the reduced vergence adaptation in CI leads to excessive amounts of convergence accommodation (CA). Eleven CI participants (mean age=17.4±2.3 years) were recruited with reduced capacity to view through increasing magnitudes of base out (BO) prisms (mean fusional convergence at 40 cm=12±0.9Δ). Testing followed our previous experimental design for (n=11) binocularly normal adults. Binocular fixation of a difference of Gaussian (DoG) target (0.2 cpd) elicited CA responses during vergence adaptation to a 12Δ BO. Vergence and CA responses were obtained at 3 min intervals over a 15 min period and time course were quantified using exponential decay functions. Results were compared to previously published data on eleven binocular normals. Eight participants completed the study. CI's showed significantly reduced magnitude of vergence adaptation (CI: 2.9Δ vs. normals: 6.6Δ; p=0.01) and CA reduction (CI=0.21 D, Normals=0.55 D; p=0.03). However, the decay time constants for adaptation and CA responses were not significantly different. CA changes were not confounded by changes in tonic accommodation (Change in TA=0.01±0.2D; p=0.8). The reduced magnitude of vergence adaptation found in CI patients resulting in higher levels of CA may potentially explain their clinical findings of reduced positive fusional vergence (PFV) and the common symptom of blur. Copyright © 2014 Elsevier B.V. All rights reserved.

  13. Toward Massive, Ultrareliable, and Low-Latency Wireless Communication With Short Packets

    DEFF Research Database (Denmark)

    Durisi, Giuseppe; Koch, Tobias; Popovski, Petar

    2016-01-01

    Most of the recent advances in the design of high-speed wireless systems are based on information-theoretic principles that demonstrate how to efficiently transmit long data packets. However, the upcoming wireless systems, notably the fifth-generation (5G) system, will need to support novel traffic...... that should be received with low latency and ultrahigh reliability. Current wireless systems are not designed to support short-packet transmissions. For example, the design of current systems relies on the assumption that the metadata (control information) is of negligible size compared to the actual...

  14. Temporal Integration of Auditory Stimulation and Binocular Disparity Signals

    Directory of Open Access Journals (Sweden)

    Marina Zannoli

    2011-10-01

    Full Text Available Several studies using visual objects defined by luminance have reported that the auditory event must be presented 30 to 40 ms after the visual stimulus to perceive audiovisual synchrony. In the present study, we used visual objects defined only by their binocular disparity. We measured the optimal latency between visual and auditory stimuli for the perception of synchrony using a method introduced by Moutoussis & Zeki (1997. Visual stimuli were defined either by luminance and disparity or by disparity only. They moved either back and forth between 6 and 12 arcmin or from left to right at a constant disparity of 9 arcmin. This visual modulation was presented together with an amplitude-modulated 500 Hz tone. Both modulations were sinusoidal (frequency: 0.7 Hz. We found no difference between 2D and 3D motion for luminance stimuli: a 40 ms auditory lag was necessary for perceived synchrony. Surprisingly, even though stereopsis is often thought to be slow, we found a similar optimal latency in the disparity 3D motion condition (55 ms. However, when participants had to judge simultaneity for disparity 2D motion stimuli, it led to larger latencies (170 ms, suggesting that stereo motion detectors are poorly suited to track 2D motion.

  15. Vergence and Standing Balance in Subjects with Idiopathic Bilateral Loss of Vestibular Function.

    Directory of Open Access Journals (Sweden)

    Zoï Kapoula

    Full Text Available There is a natural symbiosis between vergence and vestibular responses. Deficits in vergence can lead to vertigo, disequilibrium, and postural instability. This study examines both vergence eye movements in patients with idiopathic bilateral vestibular loss, and their standing balance in relation to vergence. Eleven patients participated in the study and 16 controls. Bilateral loss of vestibular function was objectified with many tests; only patients without significant response to caloric tests, to video head impulse tests and without vestibular evoked myogenic potentials were included in the study.A LED display with targets at 20, 40, and 100 cm along the median plane was used to elicit vergence eye movements, recorded with the IRIS device.Four conditions were run, each lasting 1 min: fixation of a LED at 40 cm (convergence of 9°, at 150 cm (convergence of 2.3°; this last condition was repeated with eyes closed. Comparison of the eyes closed-eyes open conditions at 150 cm allowed evaluation of the Romberg Quotient. In the forth condition, two LEDS, at 20 and at 100 cm, were light on, one after the other for 1 sec, causing the eyes to converge then diverge. Standing balance was recorded with an accelerometer placed at the back near the center of mass (McRoberts, Dynaport.Relative to controls, convergence eye movements in patients showed significantly lower accuracy, lower mean velocity, and saccade intrusions of significantly higher amplitude.The normalized 90% area of body sway was significantly higher for patients than for controls for all conditions. Yet, similarly to controls, postural stability was better while fixating at near (sustained convergence than at far, or while making active vergence movements. We argue that vestibular loss deteriorates convergence, but even deficient, convergence can be helpful for postural control.

  16. Agreement between clinical and laboratory methods assessing tonic and cross-link components of accommodation and vergence.

    Science.gov (United States)

    Neveu, Pascaline; Priot, Anne-Emmanuelle; Philippe, Matthieu; Fuchs, Philippe; Roumes, Corinne

    2015-09-01

    Several tests are available to optometrists for investigating accommodation and vergence. This study sought to investigate the agreement between clinical and laboratory methods and to clarify which components are actually measured when tonic and cross-link of accommodation and vergence are assessed. Tonic vergence, tonic accommodation, accommodative vergence (AC/A) and vergence accommodation (CA/C) were measured using several tests. Clinical tests were compared to the laboratory assessment, the latter being regarded as an absolute reference. The repeatability of each test and the degree of agreement between the tests were quantified using Bland-Altman analysis. The values obtained for each test were found to be stable across repetitions; however, in most cases, significant differences were observed between tests supposed to measure the same oculomotor component. Tonic and cross-link components cannot be easily assessed because proximal and instrumental responses interfere with the assessment. Other components interfere with oculomotor assessment. Specifically, accommodative divergence interferes with tonic vergence estimation and the type of accommodation considered in the AC/A ratio affects its magnitude. Results on clinical tonic accommodation and clinical CA/C show that further investigation is needed to clarify the limitations associated with the use of difference of Gaussian as visual targets to open the accommodative loop. Although different optometric tests of accommodation and vergence rely on the same basic principles, the results of this study indicate that clinical and laboratory methods actually involve distinct components. These differences, which are induced by methodological choices, must be taken into account, when comparing studies or when selecting a test to investigate a particular oculomotor component. © 2015 The Authors. Clinical and Experimental Optometry © 2015 Optometry Australia.

  17. Cortical modulation of short-latency TMS-evoked potentials

    Directory of Open Access Journals (Sweden)

    Domenica eVeniero

    2013-01-01

    Full Text Available Transcranial magnetic stimulation - electroencephalogram (TMS-EEG co-registration offers the opportunity to test reactivity of brain areas across distinct conditions through TMS-evoked potentials (TEPs. Several TEPs have been described, their functional meaning being largely unknown. In particular, short-latency potentials peaking at 5 (P5 and 8 (N8 ms after the TMS pulse have been recently described, but because of their huge amplitude, the problem of whether their origin is cortical or not has been opened. To gain information about these components, we employed a protocol that modulates primary motor cortex excitability (MI through an exclusively cortical phenomena: low frequency stimulation of premotor area (PMC. TMS was applied simultaneously with EEG recording from 70 electrodes. Amplitude of TEPs evoked by 200 single-pulses TMS delivered over MI at 110% of resting motor threshold was measured before and after applying 900 TMS conditioning stimuli to left premotor cortex with 1 Hz repetition rate. Single subject analyses showed reduction in TEPs amplitude after PMC conditioning in a sample of participants and increase in TEPs amplitude in two subjects. No effects were found on corticospinal excitability as recorded by motor evoked potentials (MEPs. Furthermore, correlation analysis showed an inverse relation between the effects of the conditioning protocol on P5-N8 complex amplitude and MEPs amplitude. Because the effects of the used protocol have been ascribed to a cortical interaction between premotor area and MI, we suggest that despite the sign of P5-N8 amplitude modulation is not consistent across participant, this modulation could indicate, at least in part, their cortical origin. We conclude that with an accurate experimental procedure early-latency components can be used to evaluate the reactivity of the stimulated cortex.

  18. Can current models of accommodation and vergence predict accommodative behavior in myopic children?

    Science.gov (United States)

    Sreenivasan, Vidhyapriya; Irving, Elizabeth L; Bobier, William R

    2014-08-01

    Investigations into the progression of myopia in children have long considered the role of accommodation as a cause and solution. Myopic children show high levels of accommodative adaptation, coupled with accommodative lag and high response AC/A (accommodative convergence per diopter of accommodation). This pattern differs from that predicted by current models of interaction between accommodation and vergence, where weakened reflex responses and a high AC/A would be associated with a low not high levels of accommodative adaptation. However, studies of young myopes were limited to only part of the accommodative vergence synkinesis and the reciprocal components of vergence adaptation and convergence accommodation were not studied in tandem. Accordingly, we test the hypothesis that the accommodative behavior of myopic children is not predicted by current models and whether that departure is explained by differences in the accommodative plant of the myopic child. Responses to incongruent stimuli (-2D, +2D adds, 10 prism diopter base-out prism) were investigated in 28 myopic and 25 non-myopic children aged 7-15 years. Subjects were divided into phoria groups - exo, ortho and eso based upon their near phoria. The school aged myopes showed high levels of accommodative adaptation but with reduced accommodation and high AC/A. This pattern is not explained by current adult models and could reflect a sluggish gain of the accommodative plant (ciliary muscle and lens), changes in near triad innervation or both. Further, vergence adaptation showed a predictable reciprocal relationship with the high accommodative adaptation, suggesting that departures from adult models were limited to accommodation not vergence behavior. Copyright © 2014 Elsevier Ltd. All rights reserved.

  19. Accommodation and vergence status among the 3rd and 4th graders in a mainstream school in Gauteng*

    Directory of Open Access Journals (Sweden)

    I. T. Metsing

    2012-12-01

    Full Text Available Aim: The data presented in this paper is obtained from the study on the prevalence of visual deficien-cies in mainstream and learning disabled schools which revealed no difference in the prevalence of visual deficiencies in both schools. One of the objectives of this study was to determine the visual status of each learner in each of the two groups (mainstream and learning disabled. The findings of the study revealed that both groups presented with different visual deficiencies including accommodation, vergence deficiencies and poor ocular motilities which can contribute towards influencing the children’s learning skills negatively. The visual profile on the accommodative and vergence systems of the children from the mainstream school is further analysed in this paper to determine the prevalence of deficiencies in the 8-13 year-olds, and to support inclusion of the evaluation of these visual skills in the school vision screening protocol. Method: One hundred and twelve (112 children had an expanded vision screening, with eighty (80 from the mainstream school in Johannesburg aged 8-13 years. The expanded vision screeningincluded the measurement of visual acuity (Snellen Acuity, refractive error (static retinoscopy, accommodation (accuracy, facility and amplitude, evaluation of the vergence system (accuracy, facility and amplitude and ocular motilities (direct ob-servation. Of the 80 children from the mainstream school, only 73 children’s results were consideredlearning performance of children, especially those of school-going-age. The study therefore supports the expanded vision screening of all school-going-children in South Africa to include visual efficiency skills (accommodation and vergence systems for appropriate and early identification of the barriers and seven subjects were excluded due to their poor responses to the tests.Kolmogorov-Smirnov test was utilized to assess the normality of distribution of accommodative and vergence

  20. Using Weightless Neural Networks for Vergence Control in an Artificial Vision System

    Directory of Open Access Journals (Sweden)

    Karin S. Komati

    2003-01-01

    Full Text Available This paper presents a methodology we have developed and used to implement an artificial binocular vision system capable of emulating the vergence of eye movements. This methodology involves using weightless neural networks (WNNs as building blocks of artificial vision systems. Using the proposed methodology, we have designed several architectures of WNN-based artificial vision systems, in which images captured by virtual cameras are used for controlling the position of the ‘foveae’ of these cameras (high-resolution region of the images captured. Our best architecture is able to control the foveae vergence movements with average error of only 3.58 image pixels, which is equivalent to an angular error of approximately 0.629°.

  1. Achieving low latency and energy consumption by 5G TDD mode optimization

    DEFF Research Database (Denmark)

    Lähetkangas, Eeva; Pajukoski, Kari; Vihriälä, Jaakko

    2014-01-01

    and discussing on the consequent frame length limits. We then provide a description on how the achieved short TDD latency can further be utilized to enable remarkably low energy consumption. A numerical analysis comparing the battery life time of the suggested 5G TDD air interface and LTE is provided, showing......The target for a new 5G radio access technology is to support multi-Gbps and ms latency connectivity simultaneously at noticeably lower energy consumption and cost compared to the existing 4G technologies, such as LTE-Advanced. Extremely short air interface latency is required to achieve...... these requirements in a TDD-based local area network. In this paper, we discuss how the required short TDD latency can be achieved and further utilized in 5G physical air interface. First, we investigate the enablers and limits of TDD latency by analyzing the performance of OFDM in different channel environments...

  2. Racial disparities in short sleep duration by occupation and industry.

    Science.gov (United States)

    Jackson, Chandra L; Redline, Susan; Kawachi, Ichiro; Williams, Michelle A; Hu, Frank B

    2013-11-01

    Short sleep duration, which is associated with increased morbidity and mortality, has been shown to vary by occupation and industry, but few studies have investigated differences between black and white populations. By using data from a nationally representative sample of US adult short sleepers (n = 41,088) in the National Health Interview Survey in 2004-2011, we estimated prevalence ratios for short sleep duration in blacks compared with whites for each of 8 industry categories by using adjusted Poisson regression models with robust variance. Participants' mean age was 47 years; 50% were women and 13% were black. Blacks were more likely to report short sleep duration than whites (37% vs. 28%), and the black-white disparity was widest among those who held professional occupations. Adjusted short sleep duration was more prevalent in blacks than whites in the following industry categories: finance/information/real estate (prevalence ratio (PR) = 1.44, 95% confidence interval (CI): 1.30, 1.59); professional/administrative/management (PR = 1.30, 95% CI: 1.18, 1.44); educational services (PR = 1.39, 95% CI: 1.25, 1.54); public administration/arts/other services (PR = 1.30, 95% CI: 1.21, 1.41); health care/social assistance (PR = 1.23, 95% CI: 1.14, 1.32); and manufacturing/construction (PR = 1.14, 95% CI: 1.07, 1.20). Short sleep generally increased with increasing professional responsibility within a given industry among blacks but decreased with increasing professional roles among whites. Our results suggest the need for further investigation of racial/ethnic differences in the work-sleep relationship.

  3. The interaction of pupil response with the vergence system.

    Science.gov (United States)

    Feil, Moritz; Moser, Barbara; Abegg, Mathias

    2017-11-01

    A gaze shift from a target at distance to a target at near leads to pupillary constriction. The regulation of this pupillary near response is ill known. We investigated the impact of accommodation, convergence, and proximity on the pupillary diameter. We recorded pupil size and vergence eye movements with the use of an infrared eye tracker. We determined the pupillary response in four conditions: (1) after a gaze shift from far to near without accommodation, (2) after a gaze shift from far to near with neither accommodation nor convergence, (3) after accommodation alone, and (4) after accommodation with convergence without a gaze shift to near. These responses were compared to the pupil response of a full near response and to a gaze shift from one far target to another. We found a reliable pupillary near response. The removal of both accommodation and convergence in gaze shift from far to near abolished the pupillary near response. Accommodation alone did not induce pupillary constriction, while convergence and accommodation together induced a pupil response similar to the full near response. The main trigger for the pupillary response seems to be convergence. Neither accommodation nor proximity alone induce a significant pupillary constriction. This suggests that the miosis of the near triad is closely coupled to the vergence system rather than being independently regulated.

  4. Active ocular vergence improves postural control in elderly as close viewing distance with or without a single cognitive task.

    Science.gov (United States)

    Matheron, Eric; Yang, Qing; Delpit-Baraut, Vincent; Dailly, Olivier; Kapoula, Zoï

    2016-01-01

    Performance of the vestibular, visual, and somatosensory systems decreases with age, reducing the capacity of postural control, and increasing the risk of falling. The purpose of this study is to measure the effects of vision, active vergence eye movements, viewing distance/vergence angle and a simple cognitive task on postural control during an upright stance, in completely autonomous elderly individuals. Participated in the study, 23 elderly subjects (73.4 ± 6.8 years) who were enrolled in a center dedicated to the prevention of falling. Their body oscillations were measured with the DynaPort(®) device, with three accelerometers, placed at the lumbosacral level, near the center of mass. The conditions were the following: eyes open fixating on LED at 20 cm or 150 cm (vergence angle 17.0° and 2.3° respectively) with or without additional cognitive tasks (counting down from one hundred), performing active vergence by alternating the fixation between the far and the near LED (convergence and divergence), eyes closed after having fixated the far LED. The results showed that the postural stability significantly decreased when fixating on the LED at a far distance (weak convergence angle) with or without cognitive tasks; active convergence-divergence between the LEDs improved the postural stability while eye closure decreased it. The privilege of proximity (with increased convergence at near), previously established with foot posturography, is shown here to be valid for accelerometry with the center of mass in elderly. Another major result is the beneficial contribution of active vergence eye movements to better postural stability. The results bring new perspectives for the role of eye movement training to preserve postural control and autonomy in elderly. Copyright © 2015 Elsevier Ireland Ltd. All rights reserved.

  5. Phenotypic disparity in Iberian short-horned grasshoppers (Acrididae): the role of ecology and phylogeny.

    Science.gov (United States)

    García-Navas, Vicente; Noguerales, Víctor; Cordero, Pedro J; Ortego, Joaquín

    2017-05-04

    The combination of model-based comparative techniques, disparity analyses and ecomorphological correlations constitutes a powerful method to gain insight into the evolutionary mechanisms that shape morphological variation and speciation processes. In this study, we used a time-calibrated phylogeny of 70 Iberian species of short-horned grasshoppers (Acrididae) to test for patterns of morphological disparity in relation to their ecology and phylogenetic history. Specifically, we examined the role of substrate type and level of ecological specialization in driving different aspects of morphological evolution (locomotory traits, chemosensitive organs and cranial morphology) in this recent radiation. We found a bimodal distribution of locomotory attributes corresponding to the two main substrate type guilds (plant vs. ground); plant-perching species tend to exhibit larger wings and thicker femora than those that remain on the ground. This suggests that life form (i.e., substrate type) is an important driving force in the evolution of morphological traits in short-horned grasshoppers, irrespective of ancestry. Substrate type and ecological specialization had no significant influence on head shape, a trait that showed a strong phylogenetic conservatism. Finally, we also found a marginal significant association between the length of antennae and the level of ecological specialization, suggesting that the development of sensory organs may be favored in specialist species. Our results provide evidence that even in taxonomic groups showing limited morphological and ecological disparity, natural selection seems to play a more important role than genetic drift in driving the speciation process. Overall, this study suggests that morphostatic radiations should not necessarily be considered as "non-adaptive" and that the speciation process can bind both adaptive divergence mechanisms and neutral speciation processes related with allopatric and/or reproductive isolation.

  6. Origin and function of short-latency inputs to the neural substrates underlying the acoustic startle reflex

    Directory of Open Access Journals (Sweden)

    Ricardo eGómez-Nieto

    2014-07-01

    Full Text Available The acoustic startle reflex (ASR is a survival mechanism of alarm, which rapidly alerts the organism to a sudden loud auditory stimulus. In rats, the primary ASR circuit encompasses three serially connected structures: cochlear root neurons (CRNs, neurons in the caudal pontine reticular nucleus (PnC, and motoneurons in the medulla and spinal cord. It is well established that both CRNs and PnC neurons receive short-latency auditory inputs to mediate the ASR. Here, we investigated the anatomical origin and functional role of these inputs using a multidisciplinary approach that combines morphological, electrophysiological and behavioural techniques. Anterograde tracer injections into the cochlea suggest that CRNs somata and dendrites receive inputs depending, respectively, on their basal or apical cochlear origin. Confocal colocalization experiments demonstrated that these cochlear inputs are immunopositive for the vesicular glutamate transporter 1. Using extracellular recordings in vivo followed by subsequent tracer injections, we investigated the response of PnC neurons after contra-, ipsi-, and bilateral acoustic stimulation and identified the source of their auditory afferents. Our results showed that the binaural firing rate of PnC neurons was higher than the monaural, exhibiting higher spike discharges with contralateral than ipsilateral acoustic stimulations. Our histological analysis confirmed the CRNs as the principal source of short-latency acoustic inputs, and indicated that other areas of the cochlear nucleus complex are not likely to innervate PnC. Behaviourally, we observed a strong reduction of ASR amplitude in monaural earplugged rats that corresponds with the binaural summation process shown in our electrophysiological findings. Our study contributes to understand better the role of neuronal mechanisms in auditory alerting behaviours and provides strong evidence that the CRNs-PnC pathway mediates fast neurotransmission and binaural

  7. Dynamic modulation of corticospinal excitability and short-latency afferent inhibition during onset and maintenance phase of selective finger movement.

    Science.gov (United States)

    Cho, Hyun Joo; Panyakaew, Pattamon; Thirugnanasambandam, Nivethida; Wu, Tianxia; Hallett, Mark

    2016-06-01

    During highly selective finger movement, corticospinal excitability is reduced in surrounding muscles at the onset of movement but this phenomenon has not been demonstrated during maintenance of movement. Sensorimotor integration may play an important role in selective movement. We sought to investigate how corticospinal excitability and short-latency afferent inhibition changes in active and surrounding muscles during onset and maintenance of selective finger movement. Using transcranial magnetic stimulation (TMS) and paired peripheral stimulation, input-output recruitment curve and short-latency afferent inhibition (SAI) were measured in the first dorsal interosseus and abductor digiti minimi muscles during selective index finger flexion. Motor surround inhibition was present only at the onset phase, but not at the maintenance phase of movement. SAI was reduced at onset but not at the maintenance phase of movement in both active and surrounding muscles. Our study showed dynamic changes in corticospinal excitability and sensorimotor modulation for active and surrounding muscles in different movement states. SAI does not appear to contribute to motor surround inhibition at the movement onset phase. Also, there seems to be different inhibitory circuit(s) other than SAI for the movement maintenance phase in order to delineate the motor output selectively when corticospinal excitability is increased in both active and surrounding muscles. This study enhances our knowledge of dynamic changes in corticospinal excitability and sensorimotor interaction in different movement states to understand normal and disordered movements. Published by Elsevier Ireland Ltd.

  8. Factors influencing the latency of simple reaction time.

    Science.gov (United States)

    Woods, David L; Wyma, John M; Yund, E William; Herron, Timothy J; Reed, Bruce

    2015-01-01

    Simple reaction time (SRT), the minimal time needed to respond to a stimulus, is a basic measure of processing speed. SRTs were first measured by Francis Galton in the 19th century, who reported visual SRT latencies below 190 ms in young subjects. However, recent large-scale studies have reported substantially increased SRT latencies that differ markedly in different laboratories, in part due to timing delays introduced by the computer hardware and software used for SRT measurement. We developed a calibrated and temporally precise SRT test to analyze the factors that influence SRT latencies in a paradigm where visual stimuli were presented to the left or right hemifield at varying stimulus onset asynchronies (SOAs). Experiment 1 examined a community sample of 1469 subjects ranging in age from 18 to 65. Mean SRT latencies were short (231, 213 ms when corrected for hardware delays) and increased significantly with age (0.55 ms/year), but were unaffected by sex or education. As in previous studies, SRTs were prolonged at shorter SOAs and were slightly faster for stimuli presented in the visual field contralateral to the responding hand. Stimulus detection time (SDT) was estimated by subtracting movement initiation time, measured in a speeded finger tapping test, from SRTs. SDT latencies averaged 131 ms and were unaffected by age. Experiment 2 tested 189 subjects ranging in age from 18 to 82 years in a different laboratory using a larger range of SOAs. Both SRTs and SDTs were slightly prolonged (by 7 ms). SRT latencies increased with age while SDT latencies remained stable. Precise computer-based measurements of SRT latencies show that processing speed is as fast in contemporary populations as in the Victorian era, and that age-related increases in SRT latencies are due primarily to slowed motor output.

  9. Factors influencing the latency of simple reaction time

    Directory of Open Access Journals (Sweden)

    David L Woods

    2015-03-01

    Full Text Available Simple reaction time (SRT, the minimal time needed to respond to a stimulus, is a basic measure of processing speed. SRTs were first measured by Francis Galton in the 19th century who reported visual SRT latencies below 190 ms in young subjects. However, recent large-scale studies have reported substantially increased SRT latencies that differ markedly in different laboratories, in part due to timing delays introduced by computer hardware and software used for SRT measurement. We developed a calibrated and temporally-precise SRT paradigm to analyze the factors that influence SRT latencies in a paradigm where visual stimuli were presented to the left or right hemifield at varying stimulus onset asynchronies (SOAs. Experiment 1 examined a community sample of 1469 subjects ranging in age from 18 to 65. Mean SRT latencies were short (231 ms, 213 ms when corrected for hardware delays and increased significantly with age (0.55 ms/year, but were unaffected by sex or education. As in previous studies, SRTs were prolonged at shorter SOAs and were slightly faster for stimuli presented in the visual field contralateral to the responding hand. Stimulus detection time (SDT was estimated by subtracting movement-initiation time, measured in a speeded finger-tapping test, from SRTs. SDT latencies averaged 131 ms and were unaffected by age. Experiment 2 tested 189 subjects ranging in age from 18 to 82 years in a different laboratory using a larger range of SOAs. Both SRTs and SDTs were slightly prolonged (by 7 ms. SRT latencies increased with age while SDT latencies did not. Precise computer-based measurements of SRT latencies show that processing speed is as fast in contemporary populations as in those from the Victorian era and that age-related increases in SRT latencies are due primarily to slowed motor output.

  10. Factors influencing the latency of simple reaction time

    Science.gov (United States)

    Woods, David L.; Wyma, John M.; Yund, E. William; Herron, Timothy J.; Reed, Bruce

    2015-01-01

    Simple reaction time (SRT), the minimal time needed to respond to a stimulus, is a basic measure of processing speed. SRTs were first measured by Francis Galton in the 19th century, who reported visual SRT latencies below 190 ms in young subjects. However, recent large-scale studies have reported substantially increased SRT latencies that differ markedly in different laboratories, in part due to timing delays introduced by the computer hardware and software used for SRT measurement. We developed a calibrated and temporally precise SRT test to analyze the factors that influence SRT latencies in a paradigm where visual stimuli were presented to the left or right hemifield at varying stimulus onset asynchronies (SOAs). Experiment 1 examined a community sample of 1469 subjects ranging in age from 18 to 65. Mean SRT latencies were short (231, 213 ms when corrected for hardware delays) and increased significantly with age (0.55 ms/year), but were unaffected by sex or education. As in previous studies, SRTs were prolonged at shorter SOAs and were slightly faster for stimuli presented in the visual field contralateral to the responding hand. Stimulus detection time (SDT) was estimated by subtracting movement initiation time, measured in a speeded finger tapping test, from SRTs. SDT latencies averaged 131 ms and were unaffected by age. Experiment 2 tested 189 subjects ranging in age from 18 to 82 years in a different laboratory using a larger range of SOAs. Both SRTs and SDTs were slightly prolonged (by 7 ms). SRT latencies increased with age while SDT latencies remained stable. Precise computer-based measurements of SRT latencies show that processing speed is as fast in contemporary populations as in the Victorian era, and that age-related increases in SRT latencies are due primarily to slowed motor output. PMID:25859198

  11. A review of non-strabismic accommodative and vergence anomalies in school-age children. Part 2: Accommodative anomalies

    Directory of Open Access Journals (Sweden)

    Samuel O. Wajuihian

    2015-08-01

    Full Text Available Comfortable reading and the performance of related near point activities involve efficient accommodative and vergence systems. However, accommodative and convergence anomalies are associated with various symptoms of asthenopia that impair efficient near point tasks. In Part 1 of this two-part article, studies on vergence anomalies were reviewed. In the current paper (Part 2, anomalies of accommodation are reviewed. The aims of the latter paper were to derive the prevalence and distribution estimates of anomalies of accommodation in school-age children and address variations in the study methods and findings. Despite variations in the study methods and findings, anomalies of accommodation are prevalent among school-age populations. Variations and limitations of previous studies are discussed and recommendations for improving future studies are suggested.

  12. Individual differences in sound-in-noise perception are related to the strength of short-latency neural responses to noise.

    Directory of Open Access Journals (Sweden)

    Ekaterina Vinnik

    2011-02-01

    Full Text Available Important sounds can be easily missed or misidentified in the presence of extraneous noise. We describe an auditory illusion in which a continuous ongoing tone becomes inaudible during a brief, non-masking noise burst more than one octave away, which is unexpected given the frequency resolution of human hearing. Participants strongly susceptible to this illusory discontinuity did not perceive illusory auditory continuity (in which a sound subjectively continues during a burst of masking noise when the noises were short, yet did so at longer noise durations. Participants who were not prone to illusory discontinuity showed robust early electroencephalographic responses at 40-66 ms after noise burst onset, whereas those prone to the illusion lacked these early responses. These data suggest that short-latency neural responses to auditory scene components reflect subsequent individual differences in the parsing of auditory scenes.

  13. Statistical Multiplexing of Computations in C-RAN with Tradeoffs in Latency and Energy

    DEFF Research Database (Denmark)

    Kalør, Anders Ellersgaard; Agurto Agurto, Mauricio Ignacio; Pratas, Nuno

    2017-01-01

    frame duration, then this may result in additional access latency and limit the energy savings. In this paper we investigate the tradeoff by considering two extreme time-scales for the resource multiplexing: (i) long-term, where the computational resources are adapted over periods much larger than...... the access frame durations; (ii) short-term, where the adaption is below the access frame duration.We develop a general C-RAN queuing model that models the access latency and show, for Poisson arrivals, that long-term multiplexing achieves savings comparable to short-term multiplexing, while offering low...

  14. Factors of Influence on the Performance of a Short-Latency Non-Invasive Brain Switch: Evidence in Healthy Individuals and Implication for Motor Function Rehabilitation

    Directory of Open Access Journals (Sweden)

    Ren eXu

    2016-01-01

    Full Text Available Brain-computer interfacing (BCI has recently been applied as a rehabilitation approach for patients with motor disorders, such as stroke. In these closed-loop applications, a brain switch detects the motor intention from brain signals, e.g. scalp EEG, and triggers a neuroprosthetic device, either to deliver sensory feedback or to mimic real movements, thus re-establishing the compromised sensory-motor control loop and promoting neural plasticity. In this context, single trial detection of motor intention with short latency is a prerequisite. The performance of the event detection from EEG recordings is mainly determined by three factors: the type of motor imagery (e.g., repetitive, ballistic, the frequency band (or signal modality used for discrimination (e.g., alpha, beta, gamma, and MRCP, i.e. movement-related cortical potential, and the processing technique (e.g., time-series analysis, sub-band power estimation. In this study, we investigated single trial EEG traces during movement imagination on healthy individuals, and provided a comprehensive analysis of the performance of a short-latency brain switch when varying these three factors. The morphological investigation showed a cross-subject consistency of a prolonged negative phase in MRCP, and a delayed beta rebound in sensory-motor rhythms during repetitive tasks. The detection performance had the greatest accuracy when using ballistic MRCP with time-series analysis. In this case, the true positive rate was ~70% for a detection latency of ~200 ms. The results presented here are of practical relevance for designing BCI systems for motor function rehabilitation.

  15. Asian-White disparities in short sleep duration by industry of employment and occupation in the US: a cross-sectional study.

    Science.gov (United States)

    Jackson, Chandra L; Kawachi, Ichiro; Redline, Susan; Juon, Hee-Soon; Hu, Frank B

    2014-06-03

    Although short sleep is associated with an increased risk of morbidity as well as mortality and has been shown to vary by industry of employment and occupation, little is known about the relationship between work and sleep among Asian Americans. Using a nationally representative sample of US adults (n = 125,610) in the National Health Interview Survey from 2004-2011, we estimated prevalence ratios for self-reported short sleep duration (hours) in Asians compared to Whites by industry of employment and occupation using adjusted Poisson regression models with robust variance. Asians were more likely to report short sleep duration than Whites (33 vs. 28%, p Asian-White disparity was widest in finance/information and healthcare industries. Compared to Whites after adjustments, short sleep was also more prevalent among Asians employed in Public administration (PR = 1.35 [95% CI: 1.17,1.56]), Education (PR = 1.29 [95% CI: 1.08,1.53]), and Professional/Management (PR = 1.18 [95% CI: 1.03,1.36]). Short sleep, however, was lower among Asians in Accommodation/Food (PR = 0.81 [95% CI: 0.66, 0.99]) with no difference in Retail. In professional and support-service occupations, short sleep was higher among Asians, but was not different among laborers. U.S. Asian-White disparities in short sleep varied by industries, suggesting a need to consider both race and occupational characteristics to identify high-risk individuals.

  16. Group II muscle afferents probably contribute to the medium latency soleus stretch reflex during walking in humans

    DEFF Research Database (Denmark)

    Grey, Michael James; Ladouceur, Michel; Andersen, Jacob B.

    2001-01-01

    1. The objective of this study was to determine which afferents contribute to the medium latency response of the soleus stretch reflex resulting from an unexpected perturbation during human walking. 2. Fourteen healthy subjects walked on a treadmill at approximately 3.5 km h(-1) with the left ankle...... = 0.007), whereas the short latency component was unchanged (P = 0.653). 7. An ankle block with lidocaine hydrochloride was performed to suppress the cutaneous afferents of the foot and ankle. Neither the short (P = 0.453) nor medium (P = 0.310) latency reflexes were changed. 8. Our results support...

  17. Fusional Vergence Detected by Prism Bar and Synoptophore in Chinese Childhood Intermittent Exotropia

    Directory of Open Access Journals (Sweden)

    Tao Fu

    2015-01-01

    Full Text Available Purpose. To measure the changes in fusional vergence in Chinese children with intermittent exotropia (IXT and the association with the control of IXT. Methods. Ninety-two patients with IXT (8–15 years old were compared with 86 controls. Exodeviation control was evaluated using the Revised Newcastle Control Score. Angle of deviation was measured using prism and alternate cover testing at distance and near. Fusional vergence was measured using prism bar and synoptophore. This study was registered with ChiCTR-RCC-13003920. Results. Using prism bar, convergence break points were lower whereas divergence break points were higher in children with IXT at distance (P<0.001 and near (P<0.001 compared with controls. There was no significant difference in mean divergence amplitudes between the two groups when testing using a synoptophore (P=0.53. In children with IXT, the distance between recovery point and break point in both convergence (distance: P=0.02; near: P=0.02 and divergence (distance: P<0.001; near: P<0.001 was larger than controls when detected by prism bar and synoptophore (convergence: P=0.005; divergence: P=0.006. Conclusions. Children with IXT have reduced convergence amplitudes as detected by both prism bar and synoptophore.

  18. Triceps surae short latency stretch reflexes contribute to ankle stiffness regulation during human running.

    Directory of Open Access Journals (Sweden)

    Neil J Cronin

    Full Text Available During human running, short latency stretch reflexes (SLRs are elicited in the triceps surae muscles, but the function of these responses is still a matter of controversy. As the SLR is primarily mediated by Ia afferent nerve fibres, various methods have been used to examine SLR function by selectively blocking the Ia pathway in seated, standing and walking paradigms, but stretch reflex function has not been examined in detail during running. The purpose of this study was to examine triceps surae SLR function at different running speeds using Achilles tendon vibration to modify SLR size. Ten healthy participants ran on an instrumented treadmill at speeds between 7 and 15 km/h under 2 Achilles tendon vibration conditions: no vibration and 90 Hz vibration. Surface EMG from the triceps surae and tibialis anterior muscles, and 3D lower limb kinematics and ground reaction forces were simultaneously collected. In response to vibration, the SLR was depressed in the triceps surae muscles at all speeds. This coincided with short-lasting yielding at the ankle joint at speeds between 7 and 12 km/h, suggesting that the SLR contributes to muscle stiffness regulation by minimising ankle yielding during the early contact phase of running. Furthermore, at the fastest speed of 15 km/h, the SLR was still depressed by vibration in all muscles but yielding was no longer evident. This finding suggests that the SLR has greater functional importance at slow to intermediate running speeds than at faster speeds.

  19. Fast response electromagnetic follow-ups from low latency GW triggers

    International Nuclear Information System (INIS)

    Howell, E J; Chu, Q; Rowlinson, A; Wen, L; Gao, H; Zhang, B; Tingay, S J; Boër, M

    2016-01-01

    We investigate joint low-latency gravitational wave (GW) detection and prompt electromagnetic (EM) follow-up observations of coalescing binary neutron stars (BNSs). Assuming that BNS mergers are associated with short duration gamma ray bursts (SGRBs), we evaluate if rapid EM follow-ups can capture the prompt emission, early engine activity or reveal any potential by-products such as magnetars or fast radio bursts. To examine the expected performance of extreme low-latency search pipelines, we simulate a population of coalescing BNSs and use these to estimate the detectability and localisation efficiency at different times before merger. Using observational SGRB flux data corrected to the range of the advanced GW interferometric detectors, we determine what EM observations could be achieved from low-frequency radio up to high energy γ-ray. We show that while challenging, breakthrough multi-messenger science is possible through low latency pipelines. (paper)

  20. Short latency compound action potentials from mammalian gravity receptor organs

    Science.gov (United States)

    Jones, T. A.; Jones, S. M.

    1999-01-01

    Gravity receptor function was characterized in four mammalian species using far-field vestibular evoked potentials (VsEPs). VsEPs are compound action potentials of the vestibular nerve and central relays that are elicited by linear acceleration ramps applied to the cranium. Rats, mice, guinea pigs, and gerbils were studied. In all species, response onset occurred within 1.5 ms of the stimulus onset. Responses persisted during intense (116 dBSPL) wide-band (50 to 50 inverted question mark omitted inverted question mark000 Hz) forward masking, whereas auditory responses to intense clicks (112 dBpeSPL) were eliminated under the same conditions. VsEPs remained after cochlear extirpation but were eliminated following bilateral labyrinthectomy. Responses included a series of positive and negative peaks that occurred within 8 ms of stimulus onset (range of means at +6 dBre: 1.0 g/ms: P1=908 to 1062 micros, N1=1342 to 1475 micros, P2=1632 to 1952 micros, N2=2038 to 2387 micros). Mean response amplitudes at +6 dBre: 1.0 g/ms ranged from 0.14 to 0.99 microV. VsEP input/output functions revealed latency slopes that varied across peaks and species ranging from -19 to -51 micros/dB. Amplitude-intensity slopes also varied ranging from 0.04 to 0.08 microV/dB for rats and mice. Latency values were comparable to those of birds although amplitudes were substantially smaller in mammals. VsEP threshold values were considerably higher in mammals compared to birds and ranged from -8.1 to -10.5 dBre 1.0 g/ms across species. These results support the hypothesis that mammalian gravity receptors are less sensitive to dynamic stimuli than are those of birds.

  1. Accommodation modulates the individual difference between objective and subjective measures of the final convergence step response.

    Science.gov (United States)

    Jainta, S; Hoormann, J; Jaschinski, W

    2009-03-01

    Measuring vergence eye movements with dichoptic nonius lines (subjectively) usually leads to an overestimation of the vergence state after a step response: a subjective vergence overestimation (SVO). We tried to reduce this SVO by presenting a vergence stimulus that decoupled vergence and accommodation during the step response, i.e. reduced the degree of 'forced vergence'. In a mirror-stereoscope, we estimated convergence step responses with nonius lines presented at 1000 ms after a disparity step-stimulus and compared it to objective recordings (EyeLink II; n = 6). We presented a vertical line, a cross/rectangle stimulus and a difference-of-gaussians (DOG) pattern. For 180 min arc step stimuli, the subjective measures revealed a larger final vergence response than the objective measure; for the vertical line this SVO was 20 min arc, while it was significantly smaller for the DOG (12 min arc). For 60 min arc step-responses, no overestimation was observed. Additionally, we measured accommodation, which changed more for the DOG-pattern compared with the line-stimulus; this relative increase correlated with the corresponding relative change of SVO (r = 0.77). Both findings (i.e. no overestimation for small steps and a weaker one for the DOG-pattern) reflect lesser conflicting demand on accommodation and vergence under 'forced-vergence' viewing; consequently, sensory compensation is reduced and subjective and objective measures of vergence step responses tend to agree.

  2. The use of cues to convergence and accommodation in naïve, uninstructed participants.

    Science.gov (United States)

    Horwood, Anna M; Riddell, Patricia M

    2008-07-01

    A remote haploscopic video refractor was used to assess vergence and accommodation responses in a group of 32 emmetropic, orthophoric, symptom free, young adults naïve to vision experiments in a minimally instructed setting. Picture targets were presented at four positions between 2 m and 33 cm. Blur, disparity and looming cues were presented in combination or separately to asses their contributions to the total near response in a within-subjects design. Response gain for both vergence and accommodation reduced markedly whenever disparity was excluded, with much smaller effects when blur and proximity were excluded. Despite the clinical homogeneity of the participant group there were also some individual differences.

  3. Evaluation of ocular accommodation, convergence and fusional vergence changes during Ramadan

    Directory of Open Access Journals (Sweden)

    Seyed Hosein Hoseini-Yazdi

    2013-03-01

    Full Text Available Purpose: There are a few researches regarding the effects of Islamic fasting on visual system. The aim of this study was to investigate the effects of Ramadan fasting on the amplitude of accommodation (AA, near point of convergence (NPC, positive and negative fusional vergences (PFV and NFV, respectively in visually healthy fasters. Methods: AA, NPC, PFV and NFV at far (6m and near (40cm were measured in 30 male students. Nutritional habits in a week before each examination visit were assessed with the Food Frequency Questionnaire (FFQ. Results: Mean age and fasting average experience were 23.9 and 10 years, respectively. AA and NPC showed significant changes (p

  4. Central and peripheral components of short latency vestibular responses in the chicken

    Science.gov (United States)

    Nazareth, A. M.; Jones, T. A.

    1998-01-01

    Far-field recordings of short latency vestibular responses to pulsed cranial translation are composed of a series of positive and negative peaks occurring within 10 ms following stimulus onset. In the bird, these vestibular evoked potentials (VsEPs) can be recorded noninvasively and have been shown in the chicken and quail to depend strictly upon the activation of the vestibular component of the eighth nerve. The utility of the VsEP in the study of vestibular systems is dependent upon a clear understanding of the neural sources of response components. The primary aim of the current research in the chicken was to critically test the hypotheses that 1) responses are generated by both peripheral and central neurons and 2) peaks P1 and N1 originate from first order vestibular neurons, whereas later waves primarily depend on activity in higher order neurons. The principal strategy used here was to surgically isolate the eighth nerve as it enters the brainstem. Interruption of primary afferents of the eighth nerve in the brainstem substantially reduced or eliminated peaks beyond P2, whereas P1 and N1 were generally spared. Surgical sections that spared vestibular pathways had little effect on responses. The degree of change in response components beyond N1 was correlated with the extent of damage to central vestibular relays. These findings support the conclusion that responses are produced by both peripheral and central elements of the vestibular system. Further, response peaks later than N1 appear to be dependent upon central relays, whereas P1 and N1 reflect activity of the peripheral nerve. These findings clarify the roles of peripheral and central neurons in the generation of vestibular evoked potentials and provide the basis for a more useful and detailed interpretation of data from vestibular response testing.

  5. Explaining Disparities in Unemployment Dynamics

    OpenAIRE

    Karanassou, Marika; Snower, Dennis J.

    1993-01-01

    This paper attempts to explain disparities among the unemployment experiences of different OECD countries in terms of the `fragility' of the short-run unemployment equilibrium (the impact of labour market shocks on the short-run unemployment rate) and the lag structure of the employment determination, wage setting, and labour force participation decisions. The effects of this lag structure on unemployment dynamics are captured through two general measures of `unemployment persistence' (occurr...

  6. Influence of P300 latency jitter on event related potential-based brain-computer interface performance

    Science.gov (United States)

    Aricò, P.; Aloise, F.; Schettini, F.; Salinari, S.; Mattia, D.; Cincotti, F.

    2014-06-01

    Objective. Several ERP-based brain-computer interfaces (BCIs) that can be controlled even without eye movements (covert attention) have been recently proposed. However, when compared to similar systems based on overt attention, they displayed significantly lower accuracy. In the current interpretation, this is ascribed to the absence of the contribution of short-latency visual evoked potentials (VEPs) in the tasks performed in the covert attention modality. This study aims to investigate if this decrement (i) is fully explained by the lack of VEP contribution to the classification accuracy; (ii) correlates with lower temporal stability of the single-trial P300 potentials elicited in the covert attention modality. Approach. We evaluated the latency jitter of P300 evoked potentials in three BCI interfaces exploiting either overt or covert attention modalities in 20 healthy subjects. The effect of attention modality on the P300 jitter, and the relative contribution of VEPs and P300 jitter to the classification accuracy have been analyzed. Main results. The P300 jitter is higher when the BCI is controlled in covert attention. Classification accuracy negatively correlates with jitter. Even disregarding short-latency VEPs, overt-attention BCI yields better accuracy than covert. When the latency jitter is compensated offline, the difference between accuracies is not significant. Significance. The lower temporal stability of the P300 evoked potential generated during the tasks performed in covert attention modality should be regarded as the main contributing explanation of lower accuracy of covert-attention ERP-based BCIs.

  7. Scalable optical packet switch architecture for low latency and high load computer communication networks

    NARCIS (Netherlands)

    Calabretta, N.; Di Lucente, S.; Nazarathy, Y.; Raz, O.; Dorren, H.J.S.

    2011-01-01

    High performance computer and data-centers require PetaFlop/s processing speed and Petabyte storage capacity with thousands of low-latency short link interconnections between computers nodes. Switch matrices that operate transparently in the optical domain are a potential way to efficiently

  8. Latency in Distributed Acquisition and Rendering for Telepresence Systems.

    Science.gov (United States)

    Ohl, Stephan; Willert, Malte; Staadt, Oliver

    2015-12-01

    Telepresence systems use 3D techniques to create a more natural human-centered communication over long distances. This work concentrates on the analysis of latency in telepresence systems where acquisition and rendering are distributed. Keeping latency low is important to immerse users in the virtual environment. To better understand latency problems and to identify the source of such latency, we focus on the decomposition of system latency into sub-latencies. We contribute a model of latency and show how it can be used to estimate latencies in a complex telepresence dataflow network. To compare the estimates with real latencies in our prototype, we modify two common latency measurement methods. This presented methodology enables the developer to optimize the design, find implementation issues and gain deeper knowledge about specific sources of latency.

  9. Increased onset of vergence adaptation reduces excessive accommodation during the orthoptic treatment of convergence insufficiency.

    Science.gov (United States)

    Sreenivasan, Vidhyapriya; Bobier, William R

    2015-06-01

    This research tested the hypothesis that the successful treatment of convergence insufficiency (CI) with vision-training (VT) procedures, leads to an increased capacity of vergence adaptation (VAdapt) allowing a more rapid downward adjustment of the convergence accommodation cross-link. Nine subjects with CI were recruited from a clinical population, based upon reduced fusional vergence amplitudes, receded near point of convergence or symptomology. VAdapt and the resulting changes to convergence accommodation (CA) were measured at specific intervals over 15 min (pre-training). Separate clinical measures of the accommodative convergence cross link, horizontal fusion limits and near point of convergence were taken and a symptomology questionnaire completed. Subjects then participated in a VT program composed of 2.5h at home and 1h in-office weekly for 12-14 weeks. Clinical testing was done weekly. VAdapt and CA measures were retaken once clinical measures normalized for 2 weeks (mid-training) and then again when symptoms had cleared (post-training). VAdapt and CA responses as well as the clinical measures were taken on a control group showing normal clinical findings. Six subjects provided complete data sets. CI clinical findings reached normal levels between 4 and 7 weeks of training but symptoms, VAdapt, and CA output remained significantly different from the controls until 12-14 weeks. The hypothesis was retained. The reduced VAdapt and excessive CA found in CI were normalized through orthoptic treatment. This time course was underestimated by clinical findings but matched symptom amelioration. Copyright © 2015 Elsevier Ltd. All rights reserved.

  10. Advanced LIGO low-latency searches

    Science.gov (United States)

    Kanner, Jonah; LIGO Scientific Collaboration, Virgo Collaboration

    2016-06-01

    Advanced LIGO recently made the first detection of gravitational waves from merging binary black holes. The signal was first identified by a low-latency analysis, which identifies gravitational-wave transients within a few minutes of data collection. More generally, Advanced LIGO transients are sought with a suite of automated tools, which collectively identify events, evaluate statistical significance, estimate source position, and attempt to characterize source properties. This low-latency effort is enabling a broad multi-messenger approach to the science of compact object mergers and other transients. This talk will give an overview of the low-latency methodology and recent results.

  11. Auditory-Cortex Short-Term Plasticity Induced by Selective Attention

    Science.gov (United States)

    Jääskeläinen, Iiro P.; Ahveninen, Jyrki

    2014-01-01

    The ability to concentrate on relevant sounds in the acoustic environment is crucial for everyday function and communication. Converging lines of evidence suggests that transient functional changes in auditory-cortex neurons, “short-term plasticity”, might explain this fundamental function. Under conditions of strongly focused attention, enhanced processing of attended sounds can take place at very early latencies (~50 ms from sound onset) in primary auditory cortex and possibly even at earlier latencies in subcortical structures. More robust selective-attention short-term plasticity is manifested as modulation of responses peaking at ~100 ms from sound onset in functionally specialized nonprimary auditory-cortical areas by way of stimulus-specific reshaping of neuronal receptive fields that supports filtering of selectively attended sound features from task-irrelevant ones. Such effects have been shown to take effect in ~seconds following shifting of attentional focus. There are findings suggesting that the reshaping of neuronal receptive fields is even stronger at longer auditory-cortex response latencies (~300 ms from sound onset). These longer-latency short-term plasticity effects seem to build up more gradually, within tens of seconds after shifting the focus of attention. Importantly, some of the auditory-cortical short-term plasticity effects observed during selective attention predict enhancements in behaviorally measured sound discrimination performance. PMID:24551458

  12. The intersection of disability and healthcare disparities: a conceptual framework.

    Science.gov (United States)

    Meade, Michelle A; Mahmoudi, Elham; Lee, Shoou-Yih

    2015-01-01

    This article provides a conceptual framework for understanding healthcare disparities experienced by individuals with disabilities. While health disparities are the result of factors deeply rooted in culture, life style, socioeconomic status, and accessibility of resources, healthcare disparities are a subset of health disparities that reflect differences in access to and quality of healthcare and can be viewed as the inability of the healthcare system to adequately address the needs of specific population groups. This article uses a narrative method to identify and critique the main conceptual frameworks that have been used in analyzing disparities in healthcare access and quality, and evaluating those frameworks in the context of healthcare for individuals with disabilities. Specific models that are examined include the Aday and Anderson Model, the Grossman Utility Model, the Institute of Medicine (IOM)'s models of Access to Healthcare Services and Healthcare Disparities, and the Cultural Competency model. While existing frameworks advance understandings of disparities in healthcare access and quality, they fall short when applied to individuals with disabilities. Specific deficits include a lack of attention to cultural and contextual factors (Aday and Andersen framework), unrealistic assumptions regarding equal access to resources (Grossman's utility model), lack of recognition or inclusion of concepts of structural accessibility (IOM model of Healthcare Disparities) and exclusive emphasis on supply side of the healthcare equation to improve healthcare disparities (Cultural Competency model). In response to identified gaps in the literature and short-comings of current conceptualizations, an integrated model of disability and healthcare disparities is put forth. We analyzed models of access to care and disparities in healthcare to be able to have an integrated and cohesive conceptual framework that could potentially address issues related to access to

  13. The segment as the minimal planning unit in speech production: evidence based on absolute response latencies.

    Science.gov (United States)

    Kawamoto, Alan H; Liu, Qiang; Lee, Ria J; Grebe, Patricia R

    2014-01-01

    A minimal amount of information about a word must be phonologically and phonetically encoded before a person can begin to utter that word. Most researchers assume that the minimum is the complete word or possibly the initial syllable. However, there is some evidence that the initial segment is sufficient based on longer durations when the initial segment is primed. In two experiments in which the initial segment of a monosyllabic word is primed or not primed, we present additional evidence based on very short absolute response times determined on the basis of acoustic and articulatory onset relative to presentation of the complete target. We argue that the previous failures to find very short absolute response times when the initial segment is primed are due in part to the exclusive use of acoustic onset as a measure of response latency, the exclusion of responses with very short acoustic latencies, the manner of articulation of the initial segment (i.e., plosive vs. nonplosive), and individual differences. Theoretical implications of the segment as the minimal planning unit are considered.

  14. Reduced evolutionary rates in HIV-1 reveal extensive latency periods among replicating lineages.

    Science.gov (United States)

    Immonen, Taina T; Leitner, Thomas

    2014-10-16

    HIV-1 can persist for the duration of a patient's life due in part to its ability to hide from the immune system, and from antiretroviral drugs, in long-lived latent reservoirs. Latent forms of HIV-1 may also be disproportionally involved in transmission. Thus, it is important to detect and quantify latency in the HIV-1 life cycle. We developed a novel molecular clock-based phylogenetic tool to investigate the prevalence of HIV-1 lineages that have experienced latency. The method removes alternative sources that may affect evolutionary rates, such as hypermutation, recombination, and selection, to reveal the contribution of generation-time effects caused by latency. Our method was able to recover latent lineages with high specificity and sensitivity, and low false discovery rates, even on relatively short branches on simulated phylogenies. Applying the tool to HIV-1 sequences from 26 patients, we show that the majority of phylogenetic lineages have been affected by generation-time effects in every patient type, whether untreated, elite controller, or under effective or failing treatment. Furthermore, we discovered extensive effects of latency in sequence data (gag, pol, and env) from reservoirs as well as in the replicating plasma population. To better understand our phylogenetic findings, we developed a dynamic model of virus-host interactions to investigate the proportion of lineages in the actively replicating population that have ever been latent. Assuming neutral evolution, our dynamic modeling showed that under most parameter conditions, it is possible for a few activated latent viruses to propagate so that in time, most HIV-1 lineages will have been latent at some time in their past. These results suggest that cycling in and out of latency plays a major role in the evolution of HIV-1. Thus, no aspect of HIV-1 evolution can be fully understood without considering latency - including treatment, drug resistance, immune evasion, transmission, and pathogenesis.

  15. Effects of dynamic synapses on noise-delayed response latency of a single neuron

    Science.gov (United States)

    Uzuntarla, M.; Ozer, M.; Ileri, U.; Calim, A.; Torres, J. J.

    2015-12-01

    The noise-delayed decay (NDD) phenomenon emerges when the first-spike latency of a periodically forced stochastic neuron exhibits a maximum for a particular range of noise intensity. Here, we investigate the latency response dynamics of a single Hodgkin-Huxley neuron that is subject to both a suprathreshold periodic stimulus and a background activity arriving through dynamic synapses. We study the first-spike latency response as a function of the presynaptic firing rate f . This constitutes a more realistic scenario than previous works, since f provides a suitable biophysically realistic parameter to control the level of activity in actual neural systems. We first report on the emergence of classical NDD behavior as a function of f for the limit of static synapses. Second, we show that when short-term depression and facilitation mechanisms are included at the synapses, different NDD features can be found due to their modulatory effect on synaptic current fluctuations. For example, an intriguing double NDD (DNDD) behavior occurs for different sets of relevant synaptic parameters. Moreover, depending on the balance between synaptic depression and synaptic facilitation, single NDD or DNDD can prevail, in such a way that synaptic facilitation favors the emergence of DNDD whereas synaptic depression favors the existence of single NDD. Here we report the existence of the DNDD effect in the response latency dynamics of a neuron.

  16. Evidence that convergence rather than accommodation controls intermittent distance exotropia.

    Science.gov (United States)

    Horwood, Anna M; Riddell, Patricia M

    2012-03-01

    This study considered whether vergence drives accommodation or accommodation drives vergence during the control of distance exotropia for near fixation. High accommodative convergence to accommodation (AC/A) ratios are often used to explain this control, but the role of convergence to drive accommodation (the CA/C relationship) is rarely considered. Atypical CA/C characteristics could equally, or better, explain common clinical findings. Nineteen distance exotropes, aged 4-11 years, were compared while controlling their deviation with 27 non-exotropic controls aged 5-9 years. Simultaneous vergence and accommodation responses were measured to a range of targets incorporating different combinations of blur, disparity and looming cues at four fixation distances between 2 m and 33 cm. Stimulus and response AC/A and CA/C ratios were calculated. Accommodation responses for near targets (p = 0.017) and response gains (p = 0.026) were greater in the exotropes than in the controls. Despite higher clinical stimulus AC/A ratios, the distance exotropes showed lower laboratory response AC/A ratios (p = 0.02), but significantly higher CA/C ratios (p = 0.02). All the exotropes, whether the angle changed most with lenses ('controlled by accommodation') or on occlusion ('controlled by fusion'), used binocular disparity not blur as their main cue to target distance. Increased vergence demand to control intermittent distance exotropia for near also drives significantly more accommodation. Minus lens therapy is more likely to act by correcting overaccommodation driven by controlling convergence, rather than by inducing blur-driven vergence. The use of convergence as a major drive to accommodation explains many clinical characteristics of distance exotropia, including apparently high near stimulus AC/A ratios. © 2012 The Authors. Acta Ophthalmologica © 2012 Acta Ophthalmologica Scandinavica Foundation.

  17. On the Impact of Multi-User Traffic Dynamics on Low Latency Communications

    DEFF Research Database (Denmark)

    Gerardino, Guillermo Andrés Pocovi; Pedersen, Klaus I.; Alvarez, Beatriz Soret

    2016-01-01

    In this paper we study the downlink latency performance in a multi-user cellular network. We use a flexible 5G radio frame structure, where the TTI size is configurable on a per-user basis according to their specific service requirements. Results show that at low system loads using a short TTI (e.......g. 0.25 ms) is an attractive solution to achieve low latency communications (LLC). The main benefits come from the low transmission delay required to transmit the payloads. However, as the load increases, longer TTI configurations with lower relative control overhead (and therefore higher spectral...... efficiency) provide better performance as these better cope with the non-negligible queuing delay. The presented results allow to conclude that support for scheduling with different TTI sizes is important for LLC and should be included in the future 5G....

  18. EBV Latency Types Adopt Alternative Chromatin Conformations

    Science.gov (United States)

    Tempera, Italo; Klichinsky, Michael; Lieberman, Paul M.

    2011-01-01

    Epstein-Barr Virus (EBV) can establish latent infections with distinct gene expression patterns referred to as latency types. These different latency types are epigenetically stable and correspond to different promoter utilization. Here we explore the three-dimensional conformations of the EBV genome in different latency types. We employed Chromosome Conformation Capture (3C) assay to investigate chromatin loop formation between the OriP enhancer and the promoters that determine type I (Qp) or type III (Cp) gene expression. We show that OriP is in close physical proximity to Qp in type I latency, and to Cp in type III latency. The cellular chromatin insulator and boundary factor CTCF was implicated in EBV chromatin loop formation. Combining 3C and ChIP assays we found that CTCF is physically associated with OriP-Qp loop formation in type I and OriP-Cp loop formation in type III latency. Mutations in the CTCF binding site located at Qp disrupt loop formation between Qp and OriP, and lead to the activation of Cp transcription. Mutation of the CTCF binding site at Cp, as well as siRNA depletion of CTCF eliminates both OriP-associated loops, indicating that CTCF plays an integral role in loop formation. These data indicate that epigenetically stable EBV latency types adopt distinct chromatin architectures that depend on CTCF and mediate alternative promoter targeting by the OriP enhancer. PMID:21829357

  19. EBV latency types adopt alternative chromatin conformations.

    Directory of Open Access Journals (Sweden)

    Italo Tempera

    2011-07-01

    Full Text Available Epstein-Barr Virus (EBV can establish latent infections with distinct gene expression patterns referred to as latency types. These different latency types are epigenetically stable and correspond to different promoter utilization. Here we explore the three-dimensional conformations of the EBV genome in different latency types. We employed Chromosome Conformation Capture (3C assay to investigate chromatin loop formation between the OriP enhancer and the promoters that determine type I (Qp or type III (Cp gene expression. We show that OriP is in close physical proximity to Qp in type I latency, and to Cp in type III latency. The cellular chromatin insulator and boundary factor CTCF was implicated in EBV chromatin loop formation. Combining 3C and ChIP assays we found that CTCF is physically associated with OriP-Qp loop formation in type I and OriP-Cp loop formation in type III latency. Mutations in the CTCF binding site located at Qp disrupt loop formation between Qp and OriP, and lead to the activation of Cp transcription. Mutation of the CTCF binding site at Cp, as well as siRNA depletion of CTCF eliminates both OriP-associated loops, indicating that CTCF plays an integral role in loop formation. These data indicate that epigenetically stable EBV latency types adopt distinct chromatin architectures that depend on CTCF and mediate alternative promoter targeting by the OriP enhancer.

  20. Serotonin transporter polymorphism modifies the association between depressive symptoms and sleep onset latency complaint in elderly people: results from the 'InveCe.Ab' study.

    Science.gov (United States)

    Polito, Letizia; Davin, Annalisa; Vaccaro, Roberta; Abbondanza, Simona; Govoni, Stefano; Racchi, Marco; Guaita, Antonio

    2015-04-01

    Previous studies have documented the involvement of the central nervous system serotonin in promoting wakefulness. There are few and conflicting results over whether there is an actual association between bearing the short allele of serotonin transporter promoter polymorphism (5-HTTLPR) and worse sleep quality. This study examined whether sleep onset latency complaint is associated with the 5-HTTLPR triallelic polymorphism in the SLC6A4 gene promoter and whether this polymorphism influences the relationship between sleep onset latency complaint and depressive symptoms in elderly people. A total of 1321 community-dwelling individuals aged 70-74 years were interviewed for sleep onset latency complaint and for sleep medication consumption. Participants' genomic DNA was typed for 5-HTTLPR and rs25531 polymorphisms. Depressive symptoms were evaluated with the Geriatric Depression Scale Short form and general medical comorbidity was assessed by the Cumulative Illness Rating Scale. The presence of a past history of depression was recorded. The S' allele of the 5-HTTLPR triallelic polymorphism was associated with sleep onset latency complaint. This association was maintained after adjusting for depressive symptoms, sex, age, history of depression and medical comorbidity. After stratification for 5-HTTLPR/rs25531, only in S'S' individuals high depressive symptoms were actually associated with sleep onset latency complaint. These data indicate that the low-expressing 5-HTTLPR triallelic polymorphism is an independent risk factor for sleep onset latency disturbance. Furthermore, the 5-HTTLPR genotype influences the association between depressive symptoms and sleep onset latency complaint. © 2014 European Sleep Research Society.

  1. Immaturity of the Oculomotor Saccade and Vergence Interaction in Dyslexic Children: Evidence from a Reading and Visual Search Study

    Science.gov (United States)

    Bucci, Maria Pia; Nassibi, Naziha; Gerard, Christophe-Loic; Bui-Quoc, Emmanuel; Seassau, Magali

    2012-01-01

    Studies comparing binocular eye movements during reading and visual search in dyslexic children are, at our knowledge, inexistent. In the present study we examined ocular motor characteristics in dyslexic children versus two groups of non dyslexic children with chronological/reading age-matched. Binocular eye movements were recorded by an infrared system (mobileEBT®, e(ye)BRAIN) in twelve dyslexic children (mean age 11 years old) and a group of chronological age-matched (N = 9) and reading age-matched (N = 10) non dyslexic children. Two visual tasks were used: text reading and visual search. Independently of the task, the ocular motor behavior in dyslexic children is similar to those reported in reading age-matched non dyslexic children: many and longer fixations as well as poor quality of binocular coordination during and after the saccades. In contrast, chronological age-matched non dyslexic children showed a small number of fixations and short duration of fixations in reading task with respect to visual search task; furthermore their saccades were well yoked in both tasks. The atypical eye movement's patterns observed in dyslexic children suggest a deficiency in the visual attentional processing as well as an immaturity of the ocular motor saccade and vergence systems interaction. PMID:22438934

  2. Vergence increases the gain of the human angular vestibulo-ocular reflex during peripheral hyposensitivity elicited by cold thermal irrigation.

    Science.gov (United States)

    Tamás, László T; Lundberg, Yunxia W; Büki, Béla

    2018-01-01

    When viewing a far target, the gain of the horizontal vestibulo-ocular reflex (VOR) is around 1.0, but when viewing a near target there is an increased response. It has been shown that while this convergence-mediated modulation is unaffected by canal plugging and clinically practical transmastoid galvanic stimulation, it is eliminated by a partial peripheral gentamicin lesion. The aim of this study was to determine if convergence increases the gain during peripheral hyposensitivity elicited by cold thermal irrigation. The high frequency VOR gain was measured using video head impulse testing immediately after the cold caloric stimulus in 9 healthy human subjects with the lateral semicircular canals oriented approximately earth-vertical. Before caloric irrigation, near viewing (15 cm) increased the average VOR gain by 28% (from 1 to 1.28). Cold (24°C) water irrigation of the right ear decreased the gain to 0.66 (far viewing) and 0.82 (near viewing) (22% difference). Although vergence also increased the gain for impulses to the left to the same degree before caloric stimulus, the caloric irrigation itself (applied to the right ear) did not influence the gain for contralateral impulses. In our experiments vergence increased the gain of the human angular VOR during peripheral hyposensitivity elicited by cold thermal irrigation. These results suggest that cold irrigation does not abolish the function of the nonlinear/phasic vestibular afferent pathway.

  3. Short sleep duration as a contributor to racial disparities in breast cancer tumor grade

    Directory of Open Access Journals (Sweden)

    Kevin Allan

    2017-07-01

    Full Text Available Although African Americans (AAs are less likely to get breast cancer than European Americans (EAs, they get more aggressive forms. We previously showed that short sleep is associated with higher tumor grade. It is well documented that AAs get less sleep, on average, than EAs. We studied the contribution of short sleep to racial disparities in breast cancer aggressiveness among 809 invasive breast cancer patients who responded to a survey on their lifestyle. Multivariable regressions and mediation analyses were performed to assess the effect of sleep duration on the association of race with tumor grade. AAs reported shorter average sleep (mean [standard deviation] 6.57 [1.47] h than EAs (mean [standard deviation] 7.11 [1.16] h; P<0.0001 and were almost twice as likely to report less than 6 h of sleep per night (48.0% vs. 25.3%, P<0.0001. AA patients were more likely to have high-grade tumors (52.6% vs. 28.7% in EAs, P=0.0002. In multivariate analysis, race was associated with tumor grade (P<0.0001. On adjustment for sleep duration, the effect of race was reduced by 7.1%, but remained statistically significant (P=0.0006. However, the Sobel test did not indicate statistical significance (z=1.69, P=0.091. In other models accounting for these and additional confounders, we found similar results. Because of the conservative nature of the mediation analysis and smaller sample size, replication of our results in larger studies with more AA patients is warranted.

  4. Decreased accommodation during decompensation of distance exotropia.

    Science.gov (United States)

    Horwood, Anna M; Riddell, Patricia M

    2012-04-01

    Disparity cues can be a major drive to accommodation via the convergence accommodation to convergence (CA/C) linkage, but, on decompensation of exotropia, disparity cues are extinguished by suppression so this drive is lost. This study investigated accommodation and vergence responses to disparity, blur and proximal cues in a group of distance exotropes aged between 4 and 11 years both during decompensation and when exotropic. 19 participants with distance exotropia were tested using a PlusoptiXSO4 photo refractor set in a remote haploscopic device that assessed simultaneous vergence and accommodation to a range of targets incorporating different combinations of blur, disparity and proximal cues at four fixation distances between 2 m and 33 cm. Responses on decompensation were compared with those from the same children when their deviation was controlled. Manifest exotropia was more common in the more impoverished cue conditions. When decompensated for near, mean accommodation gain for the all-cue (naturalistic) target was significantly reduced (paccommodation of 2.33 D at 33 cm. The profile of near cues usage changed after decompensation, with blur and proximity driving residual responses, but these remaining cues did not compensate for loss of accommodation caused by the removal of disparity. Accommodation often reduces on decompensation of distance exotropia as the drive from convergence is extinguished, providing a further reason to try to prevent decompensation for near.

  5. The molecular basis of herpes simplex virus latency

    Science.gov (United States)

    Nicoll, Michael P; Proença, João T; Efstathiou, Stacey

    2012-01-01

    Herpes simplex virus type 1 is a neurotropic herpesvirus that establishes latency within sensory neurones. Following primary infection, the virus replicates productively within mucosal epithelial cells and enters sensory neurones via nerve termini. The virus is then transported to neuronal cell bodies where latency can be established. Periodically, the virus can reactivate to resume its normal lytic cycle gene expression programme and result in the generation of new virus progeny that are transported axonally back to the periphery. The ability to establish lifelong latency within the host and to periodically reactivate to facilitate dissemination is central to the survival strategy of this virus. Although incompletely understood, this review will focus on the mechanisms involved in the regulation of latency that centre on the functions of the virus-encoded latency-associated transcripts (LATs), epigenetic regulation of the latent virus genome and the molecular events that precipitate reactivation. This review considers current knowledge and hypotheses relating to the mechanisms involved in the establishment, maintenance and reactivation herpes simplex virus latency. PMID:22150699

  6. Effect of Illumination on Ocular Status Modifications Induced by Short-Term 3D TV Viewing

    Directory of Open Access Journals (Sweden)

    Yuanyuan Chen

    2017-01-01

    Full Text Available Objectives. This study aimed to compare changes in ocular status after 3D TV viewing under three modes of illumination and thereby identify optimal illumination for 3D TV viewing. Methods. The following measures of ocular status were assessed: the accommodative response, accommodative microfluctuation, accommodative facility, relative accommodation, gradient accommodative convergence/accommodation (AC/A ratio, phoria, and fusional vergence. The observers watched 3D television for 90 minutes through 3D shutter glasses under three illumination modes: A, complete darkness; B, back illumination (50 lx; and C, front illumination (130 lx. The ocular status of the observers was assessed both before and after the viewing. Results. After 3D TV viewing, the accommodative response and accommodative microfluctuation were significantly changed under illumination Modes A and B. The near positive fusional vergence decreased significantly after the 90-minute 3D viewing session under each illumination mode, and this effect was not significantly different among the three modes. Conclusions. Short-term 3D viewing modified the ocular status of adults. The least amount of such change occurred with front illumination, suggesting that this type of illumination is an appropriate mode for 3D shutter TV viewing.

  7. Towards Controlling Latency in Wireless Networks

    KAUST Repository

    Bouacida, Nader

    2017-04-24

    Wireless networks are undergoing an unprecedented revolution in the last decade. With the explosion of delay-sensitive applications in the Internet (i.e., online gaming and VoIP), latency becomes a major issue for the development of wireless technology. Taking advantage of the significant decline in memory prices, industrialists equip the network devices with larger buffering capacities to improve the network throughput by limiting packets drops. Over-buffering results in increasing the time that packets spend in the queues and, thus, introducing more latency in networks. This phenomenon is known as “bufferbloat”. While throughput is the dominant performance metric, latency also has a huge impact on user experience not only for real-time applications but also for common applications like web browsing, which is sensitive to latencies in order of hundreds of milliseconds. Concerns have arisen about designing sophisticated queue management schemes to mitigate the effects of such phenomenon. My thesis research aims to solve bufferbloat problem in both traditional half-duplex and cutting-edge full-duplex wireless systems by reducing delay while maximizing wireless links utilization and fairness. Our work shed lights on buffer management algorithms behavior in wireless networks and their ability to reduce latency resulting from excessive queuing delays inside oversized static network buffers without a significant loss in other network metrics. First of all, we address the problem of buffer management in wireless full-duplex networks by using Wireless Queue Management (WQM), which is an active queue management technique for wireless networks. Our solution is based on Relay Full-Duplex MAC (RFD-MAC), an asynchronous media access control protocol designed for relay full-duplexing. Compared to the default case, our solution reduces the end-to-end delay by two orders of magnitude while achieving similar throughput in most of the cases. In the second part of this thesis

  8. The Role of Binocular Disparity in Rapid Scene and Pattern Recognition

    Directory of Open Access Journals (Sweden)

    Matteo Valsecchi

    2013-04-01

    Full Text Available We investigated the contribution of binocular disparity to the rapid recognition of scenes and simpler spatial patterns using a paradigm combining backward masked stimulus presentation and short-term match-to-sample recognition. First, we showed that binocular disparity did not contribute significantly to the recognition of briefly presented natural and artificial scenes, even when the availability of monocular cues was reduced. Subsequently, using dense random dot stereograms as stimuli, we showed that observers were in principle able to extract spatial patterns defined only by disparity under brief, masked presentations. Comparing our results with the predictions from a cue-summation model, we showed that combining disparity with luminance did not per se disrupt the processing of disparity. Our results suggest that the rapid recognition of scenes is mediated mostly by a monocular comparison of the images, although we can rely on stereo in fast pattern recognition.

  9. Accommodation and convergence during sustained computer work.

    Science.gov (United States)

    Collier, Juanita D; Rosenfield, Mark

    2011-07-01

    With computer usage becoming almost universal in contemporary society, the reported prevalence of computer vision syndrome (CVS) is extremely high. However, the precise physiological mechanisms underlying CVS remain unclear. Although abnormal accommodation and vergence responses have been cited as being responsible for the symptoms produced, there is little objective evidence to support this claim. Accordingly, this study measured both of these oculomotor parameters during a sustained period of computer use. Subjects (N = 20) were required to read text aloud from a laptop computer at a viewing distance of 50 cm for a sustained 30-minute period through their habitual refractive correction. At 2-minute intervals, the accommodative response (AR) to the computer screen was measured objectively using a Grand Seiko WAM 5500 optometer (Grand Seiko, Hiroshima, Japan). Additionally, the vergence response was assessed by measuring the associated phoria (AP), i.e., prism to eliminate fixation disparity, using a customized fixation disparity target that appeared on the computer screen. Subjects were asked to rate the degree of difficulty of the reading task on a scale from 1 to 10. Mean accommodation and AP values during the task were 1.07 diopters and 0.74∆ base-in (BI), respectively. The mean discomfort score was 4.9. No significant changes in accommodation or vergence were observed during the course of the 30-minute test period. There was no significant difference in the AR as a function of subjective difficulty. However, the mean AP for the subjects who reported the least and greatest discomfort during the task was 1.55∆ BI and 0, respectively (P = 0.02). CVS, after 30 minutes was worse in subjects exhibiting zero fixation disparity when compared with those subjects having a BI AP but does not appear to be related to differences in accommodation. A slightly reduced vergence response increases subject comfort during the task. Copyright © 2011 American Optometric

  10. Impact of Bimodal Traffic on Latency in Optical Burst Switching Networks

    Directory of Open Access Journals (Sweden)

    Yuhua Chen

    2008-01-01

    Full Text Available This paper analyzes the impact of bimodal traffic composition on latency in optical burst switching networks. In particular, it studies the performance degradation to short-length packets caused by longer packets, both of which are part of a heterogeneous traffic model. The paper defines a customer satisfaction index for each of the classes of traffic, and a composite satisfaction index. The impact of higher overall utilization of the network as well as that of the ratio of the traffic mix on each of the customer satisfaction indices is specifically addressed.

  11. Methodology for Calculating Latency of GPS Probe Data

    Energy Technology Data Exchange (ETDEWEB)

    Young, Stanley E [National Renewable Energy Laboratory (NREL), Golden, CO (United States); Wang, Zhongxiang [University of Maryland; Hamedi, Masoud [University of Maryland

    2017-10-01

    Crowdsourced GPS probe data, such as travel time on changeable-message signs and incident detection, have been gaining popularity in recent years as a source for real-time traffic information to driver operations and transportation systems management and operations. Efforts have been made to evaluate the quality of such data from different perspectives. Although such crowdsourced data are already in widespread use in many states, particularly the high traffic areas on the Eastern seaboard, concerns about latency - the time between traffic being perturbed as a result of an incident and reflection of the disturbance in the outsourced data feed - have escalated in importance. Latency is critical for the accuracy of real-time operations, emergency response, and traveler information systems. This paper offers a methodology for measuring probe data latency regarding a selected reference source. Although Bluetooth reidentification data are used as the reference source, the methodology can be applied to any other ground truth data source of choice. The core of the methodology is an algorithm for maximum pattern matching that works with three fitness objectives. To test the methodology, sample field reference data were collected on multiple freeway segments for a 2-week period by using portable Bluetooth sensors as ground truth. Equivalent GPS probe data were obtained from a private vendor, and their latency was evaluated. Latency at different times of the day, impact of road segmentation scheme on latency, and sensitivity of the latency to both speed-slowdown and recovery-from-slowdown episodes are also discussed.

  12. Photosensor-Based Latency Measurement System for Head-Mounted Displays

    Directory of Open Access Journals (Sweden)

    Min-Woo Seo

    2017-05-01

    Full Text Available In this paper, a photosensor-based latency measurement system for head-mounted displays (HMDs is proposed. The motion-to-photon latency is the greatest reason for motion sickness and dizziness felt by users when wearing an HMD system. Therefore, a measurement system is required to accurately measure and analyze the latency to reduce these problems. The existing measurement system does not consider the actual physical movement in humans, and its accuracy is also very low. However, the proposed system considers the physical head movement and is highly accurate. Specifically, it consists of a head position model-based rotary platform, pixel luminance change detector, and signal analysis and calculation modules. Using these modules, the proposed system can exactly measure the latency, which is the time difference between the physical movement for a user and the luminance change of an output image. In the experiment using a commercial HMD, the latency was measured to be up to 47.05 ms. In addition, the measured latency increased up to 381.17 ms when increasing the rendering workload in the HMD.

  13. A three-phase epidemiological study of short and long sleepers in a middle-aged Chinese population: prevalence and characteristics

    International Nuclear Information System (INIS)

    Hao, Y.L.; Zhang, B.; Jia, F.J.; Li, X.L.; Tang, Y.; Ren, Y.Z.; Liu, W.H.

    2014-01-01

    Epidemiological studies of short and long sleepers have not been conducted previously. We collected socioeconomic, psychological, and polysomnographic characteristics of 6501 parents (3252 men and 3249 women) of 4036 primary school children in Guangzhou city. The study data were collected in three phases. The overall prevalence of short (5 h or less) and long (10 h or more) sleep duration was 0.52 and 0.64%, respectively. Long sleepers had higher Eysenck Personality Questionnaire neuroticism scores [odds ratio (OR)=1.224, 95% confidence interval (CI)=1.047-1.409] and lower education levels (OR=0.740, 95%CI=0.631-0.849) than short sleepers. In the polysomnographic assessment, short, long, and normal sleepers (7-8 h) shared similar durations of Stage 3 sleep (short=25.7±10.7, long=20.3±7.9, and normal=28.0±12.8 min, F=1.402, P=0.181). In daytime multiple sleep latency tests, short sleepers (10/19, 52.6%) were more prone to have a short sleep latency (≤8 min) than long sleepers (2/23, 8.7%). In addition to different sleep durations, neuroticism might also contribute to differences between short and long sleepers in social achievements. Stage 3 sleep might be essential for humans. The short sleep latency (≤8 min) of short sleepers in multiple sleep latency tests should be interpreted cautiously, since it was of the same severity as required for a diagnosis of narcolepsy or idiopathic hypersomnia

  14. A three-phase epidemiological study of short and long sleepers in a middle-aged Chinese population: prevalence and characteristics

    Energy Technology Data Exchange (ETDEWEB)

    Hao, Y.L. [Department of Human Anatomy, Guangzhou Medical University, Guangzhou, China, Department of Human Anatomy, Guangzhou Medical University, Guangzhou (China); Zhang, B.; Jia, F.J.; Li, X.L.; Tang, Y. [Guangdong General Hospital, Guangdong Academy of Medical Sciences, Guangdong Mental Health Centre, Guangzhou, China, Guangdong General Hospital, Guangdong Academy of Medical Sciences, Guangdong Mental Health Centre, Guangzhou (China); Ren, Y.Z. [Zhongshan The Third People' s Hospital, Zhongshan, China, Zhongshan The Third People' s Hospital, Zhongshan (China); Liu, W.H. [Guangdong General Hospital, Guangdong Academy of Medical Sciences, Guangdong Mental Health Centre, Guangzhou, China, Guangdong General Hospital, Guangdong Academy of Medical Sciences, Guangdong Mental Health Centre, Guangzhou (China)

    2014-02-17

    Epidemiological studies of short and long sleepers have not been conducted previously. We collected socioeconomic, psychological, and polysomnographic characteristics of 6501 parents (3252 men and 3249 women) of 4036 primary school children in Guangzhou city. The study data were collected in three phases. The overall prevalence of short (5 h or less) and long (10 h or more) sleep duration was 0.52 and 0.64%, respectively. Long sleepers had higher Eysenck Personality Questionnaire neuroticism scores [odds ratio (OR)=1.224, 95% confidence interval (CI)=1.047-1.409] and lower education levels (OR=0.740, 95%CI=0.631-0.849) than short sleepers. In the polysomnographic assessment, short, long, and normal sleepers (7-8 h) shared similar durations of Stage 3 sleep (short=25.7±10.7, long=20.3±7.9, and normal=28.0±12.8 min, F=1.402, P=0.181). In daytime multiple sleep latency tests, short sleepers (10/19, 52.6%) were more prone to have a short sleep latency (≤8 min) than long sleepers (2/23, 8.7%). In addition to different sleep durations, neuroticism might also contribute to differences between short and long sleepers in social achievements. Stage 3 sleep might be essential for humans. The short sleep latency (≤8 min) of short sleepers in multiple sleep latency tests should be interpreted cautiously, since it was of the same severity as required for a diagnosis of narcolepsy or idiopathic hypersomnia.

  15. Latency and User Performance in Virtual Environments and Augmented Reality

    Science.gov (United States)

    Ellis, Stephen R.

    2009-01-01

    System rendering latency has been recognized by senior researchers, such as Professor Fredrick Brooks of UNC (Turing Award 1999), as a major factor limiting the realism and utility of head-referenced displays systems. Latency has been shown to reduce the user's sense of immersion within a virtual environment, disturb user interaction with virtual objects, and to contribute to motion sickness during some simulation tasks. Latency, however, is not just an issue for external display systems since finite nerve conduction rates and variation in transduction times in the human body's sensors also pose problems for latency management within the nervous system. Some of the phenomena arising from the brain's handling of sensory asynchrony due to latency will be discussed as a prelude to consideration of the effects of latency in interactive displays. The causes and consequences of the erroneous movement that appears in displays due to latency will be illustrated with examples of the user performance impact provided by several experiments. These experiments will review the generality of user sensitivity to latency when users judge either object or environment stability. Hardware and signal processing countermeasures will also be discussed. In particular the tuning of a simple extrapolative predictive filter not using a dynamic movement model will be presented. Results show that it is possible to adjust this filter so that the appearance of some latencies may be hidden without the introduction of perceptual artifacts such as overshoot. Several examples of the effects of user performance will be illustrated by three-dimensional tracking and tracing tasks executed in virtual environments. These experiments demonstrate classic phenomena known from work on manual control and show the need for very responsive systems if they are indented to support precise manipulation. The practical benefits of removing interfering latencies from interactive systems will be emphasized with some

  16. Vergence-mediated changes in the axis of eye rotation during the human vestibulo-ocular reflex can occur independent of eye position.

    Science.gov (United States)

    Migliaccio, Americo A; Cremer, Phillip D; Aw, Swee T; Halmagyi, G Michael; Curthoys, Ian S; Minor, Lloyd B; Todd, Michael J

    2003-07-01

    The aim of this study was to determine whether vergence-mediated changes in the axis of eye rotation in the human vestibulo-ocular reflex (VOR) would obey Listing's Law (normally associated with saccadic eye movements) independent of the initial eye position. We devised a paradigm for disassociating the saccadic velocity axis from eye position by presenting near and far targets that were centered with respect to one eye. We measured binocular 3-dimensional eye movements using search coils in ten normal subjects and 3-dimensional linear head acceleration using Optotrak in seven normal subjects. The stimuli consisted of passive, unpredictable, pitch head rotations with peak acceleration of approximately 2000 degrees /s(2 )and amplitude of approximately 20 degrees. During the pitch head rotation, each subject fixated straight ahead with one eye, whereas the other eye was adducted 4 degrees during far viewing (94 cm) and 25 degrees during near viewing (15 cm). Our data showed expected compensatory pitch rotations in both eyes, and a vergence-mediated horizontal rotation only in the adducting eye. In addition, during near viewing we observed torsional eye rotations not only in the adducting eye but also in the eye looking straight ahead. In the straight-ahead eye, the change in torsional eye velocity between near and far viewing, which began approximately 40 ms after the start of head rotation, was 10+/-6 degrees /s (mean +/- SD). This change in torsional eye velocity resulted in a 2.4+/-1.5 degrees axis tilt toward Listing's plane in that eye. In the adducting eye, the change in torsional eye velocity between near and far viewing was 16+/-6 degrees /s (mean +/- SD) and resulted in a 4.1+/-1.4 degrees axis tilt. The torsional eye velocities were conjugate and both eyes partially obeyed Listing's Law. The axis of eye rotation tilted in the direction of the line of sight by approximately one-third of the angle between the line of sight and a line orthogonal to Listing

  17. Genetic variants in RBFOX3 are associated with sleep latency

    NARCIS (Netherlands)

    Amin, N.; Allebrandt, K.V.; Spek, A.; Müller-Myhsok, B.; Hek, K.; Teder-Laving, M.; Hayward, C.; Esko, T.; van Mill, J.G.; Mbarek, H.; Watson, N.F.; Melville, S.A.; Del Greco, M.F.; Byrne, E.M.; Oole, E.; Kolcic, I.; Chen, T.; Evans, D.S.; Coresh, J.; Vogelzangs, N.; Karjalainen, J.; Willemsen, G.; Gharib, S.A.; Zgaga, L.; Mihailov, E.; Stone, K.L.; Campbell, H.; Brouwer, R.W.W.; Demirkan, A.; Isaacs, A.; Dogas, Z.; Marciante, K.; Campbell, S.; Borovecki, F.; Luik, A.I.; Li, M.; Hottenga, J.J.; Huffman, J.E.; van den Hout, M.C.G.N.; Cummings, S.R.; Aulchenko, Y.S.; Gehrman, P.R.; Uitterlinden, A.G.; Wichmann, H.E.; Müller-Nurasyid, M.; Fehrmann, R.S.N.; Montgomery, G.W.; Hofman, A.; Hong, W.; Kao, L.; Oostra, B.A.; Wright, A.F.; Vink, J.M.; Wilson, J.F.; Pramstaller, P.P.; Hicks, A.A.; Polasek, O.; Punjabi, N.M.; Redline, S.; Psaty, B.M.; Heath, A.C.; Merrow, M.; Tranah, G.J.; Gottlieb, D.J.; Boomsma, D.I.; Martin, N.G.; Rudan, I.; Tiemeier, H.; van Ijcken, W.F.J.; Penninx, B.W.J.H.; Metspalu, A.; Meitinger, T.; Franke, L.; Roenneberg, T.; van Duijn, C.M.

    2016-01-01

    Time to fall asleep (sleep latency) is a major determinant of sleep quality. Chronic, long sleep latency is a major characteristic of sleep-onset insomnia and/or delayed sleep phase syndrome. In this study we aimed to discover common polymorphisms that contribute to the genetics of sleep latency. We

  18. Latency of Modern Vandalism

    Directory of Open Access Journals (Sweden)

    Карина Анатоліївна Бочарова

    2017-03-01

    Existence latent crimes create a formation of wrong conception of its scales and condition. It causes faults in prognostication of criminality, in planning of its countermeasures. Latency of crimes connected with vandalism causes serious consequences either to state or to people.

  19. Pursuit Latency for Chromatic Targets

    Science.gov (United States)

    Mulligan, Jeffrey B.; Ellis, Stephen R. (Technical Monitor)

    1998-01-01

    The temporal dynamics of eye movement response to a change in direction of stimulus motion has been used to compare the processing speeds of different types of stimuli (Mulligan, ARVO '97). In this study, the pursuit response to colored targets was measured to test the hypothesis that the slow response of the chromatic system (as measured using traditional temporal sensitivity measures such as contrast sensitivity) results in increased eye movement latencies. Subjects viewed a small (0.4 deg) Gaussian spot which moved downward at a speed of 6.6 deg/sec. At a variable time during the trajectory, the dot's direction of motion changed by 30 degrees, either to the right or left. Subjects were instructed to pursue the spot. Eye movements were measured using a video ophthalmoscope with an angular resolution of approximately 1 arc min and a temporal sampling rate of 60 Hz. Stimuli were modulated in chrominance for a variety of hue directions, combined with a range of small luminance increments and decrements, to insure that some of the stimuli fell in the subjects' equiluminance planes. The smooth portions of the resulting eye movement traces were fit by convolving the stimulus velocity with an exponential having variable onset latency, time constant and amplitude. Smooth eye movements with few saccades were observed for all stimuli. Pursuit responses to stimuli having a significant luminance component are well-fit by exponentials having latencies and time constants on the order of 100 msec. Increases in pursuit response latency on the order of 100-200 msec are observed in response to certain stimuli, which occur in pairs of complementary hues, corresponding to the intersection of the stimulus section with the subjects' equiluminant plane. Smooth eye movements can be made in response to purely chromatic stimuli, but are slower than responses to stimuli with a luminance component.

  20. A three-phase epidemiological study of short and long sleepers in a middle-aged Chinese population: prevalence and characteristics

    Directory of Open Access Journals (Sweden)

    Y.L. Hao

    2014-02-01

    Full Text Available Epidemiological studies of short and long sleepers have not been conducted previously. We collected socioeconomic, psychological, and polysomnographic characteristics of 6501 parents (3252 men and 3249 women of 4036 primary school children in Guangzhou city. The study data were collected in three phases. The overall prevalence of short (5 h or less and long (10 h or more sleep duration was 0.52 and 0.64%, respectively. Long sleepers had higher Eysenck Personality Questionnaire neuroticism scores [odds ratio (OR=1.224, 95% confidence interval (CI=1.047-1.409] and lower education levels (OR=0.740, 95%CI=0.631-0.849 than short sleepers. In the polysomnographic assessment, short, long, and normal sleepers (7-8 h shared similar durations of Stage 3 sleep (short=25.7±10.7, long=20.3±7.9, and normal=28.0±12.8 min, F=1.402, P=0.181. In daytime multiple sleep latency tests, short sleepers (10/19, 52.6% were more prone to have a short sleep latency (≤8 min than long sleepers (2/23, 8.7%. In addition to different sleep durations, neuroticism might also contribute to differences between short and long sleepers in social achievements. Stage 3 sleep might be essential for humans. The short sleep latency (≤8 min of short sleepers in multiple sleep latency tests should be interpreted cautiously, since it was of the same severity as required for a diagnosis of narcolepsy or idiopathic hypersomnia.

  1. Monitoring data transfer latency in CMS computing operations

    CERN Document Server

    Bonacorsi, D; Magini, N; Sartirana, A; Taze, M; Wildish, T

    2015-01-01

    During the first LHC run, the CMS experiment collected tens of Petabytes of collision and simulated data, which need to be distributed among dozens of computing centres with low latency in order to make efficient use of the resources. While the desired level of throughput has been successfully achieved, it is still common to observe transfer workflows that cannot reach full completion in a timely manner due to a small fraction of stuck files which require operator intervention.For this reason, in 2012 the CMS transfer management system, PhEDEx, was instrumented with a monitoring system to measure file transfer latencies, and to predict the completion time for the transfer of a data set. The operators can detect abnormal patterns in transfer latencies while the transfer is still in progress, and monitor the long-term performance of the transfer infrastructure to plan the data placement strategy.Based on the data collected for one year with the latency monitoring system, we present a study on the different fact...

  2. A Type of Low-Latency Data Gathering Method with Multi-Sink for Sensor Networks

    Science.gov (United States)

    Sha, Chao; Qiu, Jian-mei; Li, Shu-yan; Qiang, Meng-ye; Wang, Ru-chuan

    2016-01-01

    To balance energy consumption and reduce latency on data transmission in Wireless Sensor Networks (WSNs), a type of low-latency data gathering method with multi-Sink (LDGM for short) is proposed in this paper. The network is divided into several virtual regions consisting of three or less data gathering units and the leader of each region is selected according to its residual energy as well as distance to all of the other nodes. Only the leaders in each region need to communicate with the mobile Sinks which have effectively reduced energy consumption and the end-to-end delay. Moreover, with the help of the sleep scheduling and the sensing radius adjustment strategies, redundancy in network coverage could also be effectively reduced. Simulation results show that LDGM is energy efficient in comparison with MST as well as MWST and its time efficiency on data collection is higher than one Sink based data gathering methods. PMID:27338401

  3. A Type of Low-Latency Data Gathering Method with Multi-Sink for Sensor Networks

    Directory of Open Access Journals (Sweden)

    Chao Sha

    2016-06-01

    Full Text Available To balance energy consumption and reduce latency on data transmission in Wireless Sensor Networks (WSNs, a type of low-latency data gathering method with multi-Sink (LDGM for short is proposed in this paper. The network is divided into several virtual regions consisting of three or less data gathering units and the leader of each region is selected according to its residual energy as well as distance to all of the other nodes. Only the leaders in each region need to communicate with the mobile Sinks which have effectively reduced energy consumption and the end-to-end delay. Moreover, with the help of the sleep scheduling and the sensing radius adjustment strategies, redundancy in network coverage could also be effectively reduced. Simulation results show that LDGM is energy efficient in comparison with MST as well as MWST and its time efficiency on data collection is higher than one Sink based data gathering methods.

  4. Comparison of Sleep Latency and Number of SOREMPs in the Home and Hospital With a Modified Multiple Sleep Latency Test: A Randomized Crossover Study.

    Science.gov (United States)

    Beiske, Kornelia K; Sand, Trond; Rugland, Eyvind; Stavem, Knut

    2017-05-01

    Comparison of mean sleep latencies and number of sleep-onset rapid eye movement periods (SOREMPs) between modified multiple sleep latency test (MSLT) performed in the unattended home and in-hospital laboratory setting. A randomized crossover single-blinded design. Thirty-four subjects referred to MSLT for suspected hypersomnia or narcolepsy were included. Participants were randomized to perform modified MSLT in the unattended home or in the hospital first. Scores in the two settings were compared using Wilcoxon signed-rank test or exact McNemar test. Agreement between home and hospital categorized mean sleep latency and number of SOREMPs was assessed using simple kappa (κ) and proportion agreement. Agreement between home and hospital mean sleep latency was assessed using a Bland-Altman plot and an intraclass correlation coefficient. There was no difference between home and hospital assessment of mean sleep latency (P = 0.86). Two or more SOREMPs were found more frequently on modified MSLTs performed at home compared with those at the hospital (7 and 2, respectively; P = 0.025). Agreement was moderate for categorized sleep latency (κ = 0.53) and fair for categorized SOREMPs (κ = 0.39) in the 2 settings. Analysis of mean sleep latency using intraclass correlation coefficient showed a very good agreement between the two settings. Group mean sleep latency for home modified MSLTs seems to be reliable compared with that for the attended sleep-laboratory setting. Higher rate of SOREMP in the unattended home suggests that napping in a familiar environment facilitates the transition into REM sleep. Further studies are needed to assess the normal limit, sensitivity, and specificity for SOREMP at home before the clinical utility of home-based napping can be determined.

  5. Temporal processing and long-latency auditory evoked potential in stutterers.

    Science.gov (United States)

    Prestes, Raquel; de Andrade, Adriana Neves; Santos, Renata Beatriz Fernandes; Marangoni, Andrea Tortosa; Schiefer, Ana Maria; Gil, Daniela

    Stuttering is a speech fluency disorder, and may be associated with neuroaudiological factors linked to central auditory processing, including changes in auditory processing skills and temporal resolution. To characterize the temporal processing and long-latency auditory evoked potential in stutterers and to compare them with non-stutterers. The study included 41 right-handed subjects, aged 18-46 years, divided into two groups: stutterers (n=20) and non-stutters (n=21), compared according to age, education, and sex. All subjects were submitted to the duration pattern tests, random gap detection test, and long-latency auditory evoked potential. Individuals who stutter showed poorer performance on Duration Pattern and Random Gap Detection tests when compared with fluent individuals. In the long-latency auditory evoked potential, there was a difference in the latency of N2 and P3 components; stutterers had higher latency values. Stutterers have poor performance in temporal processing and higher latency values for N2 and P3 components. Copyright © 2017 Associação Brasileira de Otorrinolaringologia e Cirurgia Cérvico-Facial. Published by Elsevier Editora Ltda. All rights reserved.

  6. Temporal processing and long-latency auditory evoked potential in stutterers

    Directory of Open Access Journals (Sweden)

    Raquel Prestes

    Full Text Available Abstract Introduction: Stuttering is a speech fluency disorder, and may be associated with neuroaudiological factors linked to central auditory processing, including changes in auditory processing skills and temporal resolution. Objective: To characterize the temporal processing and long-latency auditory evoked potential in stutterers and to compare them with non-stutterers. Methods: The study included 41 right-handed subjects, aged 18-46 years, divided into two groups: stutterers (n = 20 and non-stutters (n = 21, compared according to age, education, and sex. All subjects were submitted to the duration pattern tests, random gap detection test, and long-latency auditory evoked potential. Results: Individuals who stutter showed poorer performance on Duration Pattern and Random Gap Detection tests when compared with fluent individuals. In the long-latency auditory evoked potential, there was a difference in the latency of N2 and P3 components; stutterers had higher latency values. Conclusion: Stutterers have poor performance in temporal processing and higher latency values for N2 and P3 components.

  7. Latency reduction in online multiplayer games using detour routing

    OpenAIRE

    Ly, Cong

    2010-01-01

    Long network latency negatively impacts the performance of online multiplayer games. In this thesis, we propose a novel approach to reduce the network latency in online gaming. Our approach employs application level detour routing in which game-state update messages between two players can be forwarded through other intermediate relay nodes in order to reduce network latency. We present results from an extensive measurement study to show the potential benefits of detour routing in online game...

  8. Serotonin Transporter Promoter Region (5-HTTLPR) Polymorphism is Associated with the Intravaginal Ejaculation Latency Time in Dutch Men with Lifelong Premature Ejaculation

    NARCIS (Netherlands)

    Janssen, Paddy K. C.; Bakker, Steven C.; Réthelyi, Janos; Zwinderman, Aeilko H.; Touw, Daan J.; Olivier, Berend; Waldinger, Marcel D.

    2009-01-01

    Introduction. Lifelong premature ejaculation (LPE) is characterized by persistent intravaginal ejaculation latency times (IELTs) of less than 1 minute, and has been postulated as a neurobiological dysfunction with genetic vulnerability for the short IELTs, related to disturbances of central

  9. Serotonin transporter promoter region (5-HTTLPR) polymorphism is associated with the intravaginal ejaculation latency time in Dutch men with lifelong premature ejaculation

    NARCIS (Netherlands)

    Janssen, Paddy K C; Bakker, Steven C; Réthelyi, Janos; Zwinderman, Aeilko H; Touw, Daan J; Olivier, Berend; Waldinger, Marcel D

    INTRODUCTION: Lifelong premature ejaculation (LPE) is characterized by persistent intravaginal ejaculation latency times (IELTs) of less than 1 minute, and has been postulated as a neurobiological dysfunction with genetic vulnerability for the short IELTs, related to disturbances of central

  10. Long-latency auditory evoked potentials with verbal and nonverbal stimuli.

    Science.gov (United States)

    Oppitz, Sheila Jacques; Didoné, Dayane Domeneghini; Silva, Débora Durigon da; Gois, Marjana; Folgearini, Jordana; Ferreira, Geise Corrêa; Garcia, Michele Vargas

    2015-01-01

    Long-latency auditory evoked potentials represent the cortical activity related to attention, memory, and auditory discrimination skills. Acoustic signal processing occurs differently between verbal and nonverbal stimuli, influencing the latency and amplitude patterns. To describe the latencies of the cortical potentials P1, N1, P2, N2, and P3, as well as P3 amplitude, with different speech stimuli and tone bursts, and to classify them in the presence and absence of these data. A total of 30 subjects with normal hearing were assessed, aged 18-32 years old, matched by gender. Nonverbal stimuli were used (tone burst; 1000Hz - frequent and 4000Hz - rare); and verbal (/ba/ - frequent; /ga/, /da/, and /di/ - rare). Considering the component N2 for tone burst, the lowest latency found was 217.45ms for the BA/DI stimulus; the highest latency found was 256.5ms. For the P3 component, the shortest latency with tone burst stimuli was 298.7 with BA/GA stimuli, the highest, was 340ms. For the P3 amplitude, there was no statistically significant difference among the different stimuli. For latencies of components P1, N1, P2, N2, P3, there were no statistical differences among them, regardless of the stimuli used. There was a difference in the latency of potentials N2 and P3 among the stimuli employed but no difference was observed for the P3 amplitude. Copyright © 2015 Associação Brasileira de Otorrinolaringologia e Cirurgia Cérvico-Facial. Published by Elsevier Editora Ltda. All rights reserved.

  11. Long-latency auditory evoked potentials with verbal and nonverbal stimuli,

    Directory of Open Access Journals (Sweden)

    Sheila Jacques Oppitz

    2015-12-01

    Full Text Available ABSTRACT INTRODUCTION: Long-latency auditory evoked potentials represent the cortical activity related to attention, memory, and auditory discrimination skills. Acoustic signal processing occurs differently between verbal and nonverbal stimuli, influencing the latency and amplitude patterns. OBJECTIVE: To describe the latencies of the cortical potentials P1, N1, P2, N2, and P3, as well as P3 amplitude, with different speech stimuli and tone bursts, and to classify them in the presence and absence of these data. METHODS: A total of 30 subjects with normal hearing were assessed, aged 18-32 years old, matched by gender. Nonverbal stimuli were used (tone burst; 1000 Hz - frequent and 4000 Hz - rare; and verbal (/ba/ - frequent; /ga/, /da/, and /di/ - rare. RESULTS: Considering the component N2 for tone burst, the lowest latency found was 217.45 ms for the BA/DI stimulus; the highest latency found was 256.5 ms. For the P3 component, the shortest latency with tone burst stimuli was 298.7 with BA/GA stimuli, the highest, was 340 ms. For the P3 amplitude, there was no statistically significant difference among the different stimuli. For latencies of components P1, N1, P2, N2, P3, there were no statistical differences among them, regardless of the stimuli used. CONCLUSION: There was a difference in the latency of potentials N2 and P3 among the stimuli employed but no difference was observed for the P3 amplitude.

  12. Primary display latency criteria based on flying qualities and performance data

    Science.gov (United States)

    Funk, John D., Jr.; Beck, Corin P.; Johns, John B.

    1993-01-01

    With a pilots' increasing use of visual cue augmentation, much requiring extensive pre-processing, there is a need to establish criteria for new avionics/display design. The timeliness and synchronization of the augmented cues is vital to ensure the performance quality required for precision mission task elements (MTEs) where augmented cues are the primary source of information to the pilot. Processing delays incurred while transforming sensor-supplied flight information into visual cues are unavoidable. Relationships between maximum control system delays and associated flying qualities levels are documented in MIL-F-83300 and MIL-F-8785. While cues representing aircraft status may be just as vital to the pilot as prompt control response for operations in instrument meteorological conditions, presently, there are no specification requirements on avionics system latency. To produce data relating avionics system latency to degradations in flying qualities, the Navy conducted two simulation investigations. During the investigations, flying qualities and performance data were recorded as simulated avionics system latency was varied. Correlated results of the investigation indicates that there is a detrimental impact of latency on flying qualities. Analysis of these results and consideration of key factors influencing their application indicate that: (1) Task performance degrades and pilot workload increases as latency is increased. Inconsistency in task performance increases as latency increases. (2) Latency reduces the probability of achieving Level 1 handling qualities with avionics system latency as low as 70 ms. (3) The data suggest that the achievement of desired performance will be ensured only at display latency values below 120 ms. (4) These data also suggest that avoidance of inadequate performance will be ensured only at display latency values below 150 ms.

  13. Subtle role of latency for information diffusion in online social networks

    International Nuclear Information System (INIS)

    Xiong Fei; Wang Xi-Meng; Cheng Jun-Jun

    2016-01-01

    Information diffusion in online social networks is induced by the event of forwarding information for users, and latency exists widely in user spreading behaviors. Little work has been done to reveal the effect of latency on the diffusion process. In this paper, we propose a propagation model in which nodes may suspend their spreading actions for a waiting period of stochastic length. These latent nodes may recover their activity again. Meanwhile, the mechanism of forwarding information is also introduced into the diffusion model. Mean-field analysis and numerical simulations indicate that our model has three nontrivial results. First, the spreading threshold does not correlate with latency in neither homogeneous nor heterogeneous networks, but depends on the spreading and refractory parameter. Furthermore, latency affects the diffusion process and changes the infection scale. A large or small latency parameter leads to a larger final diffusion extent, but the intrinsic dynamics is different. Large latency implies forwarding information rapidly, while small latency prevents nodes from dropping out of interactions. In addition, the betweenness is a better descriptor to identify influential nodes in the model with latency, compared with the coreness and degree. These results are helpful in understanding some collective phenomena of the diffusion process and taking measures to restrain a rumor in social networks. (paper)

  14. Latency in Visionic Systems: Test Methods and Requirements

    Science.gov (United States)

    Bailey, Randall E.; Arthur, J. J., III; Williams, Steven P.; Kramer, Lynda J.

    2005-01-01

    A visionics device creates a pictorial representation of the external scene for the pilot. The ultimate objective of these systems may be to electronically generate a form of Visual Meteorological Conditions (VMC) to eliminate weather or time-of-day as an operational constraint and provide enhancement over actual visual conditions where eye-limiting resolution may be a limiting factor. Empirical evidence has shown that the total system delays or latencies including the imaging sensors and display systems, can critically degrade their utility, usability, and acceptability. Definitions and measurement techniques are offered herein as common test and evaluation methods for latency testing in visionics device applications. Based upon available data, very different latency requirements are indicated based upon the piloting task, the role in which the visionics device is used in this task, and the characteristics of the visionics cockpit display device including its resolution, field-of-regard, and field-of-view. The least stringent latency requirements will involve Head-Up Display (HUD) applications, where the visionics imagery provides situational information as a supplement to symbology guidance and command information. Conversely, the visionics system latency requirement for a large field-of-view Head-Worn Display application, providing a Virtual-VMC capability from which the pilot will derive visual guidance, will be the most stringent, having a value as low as 20 msec.

  15. Data latency and the user community

    Science.gov (United States)

    Escobar, V. M.; Brown, M. E.; Carroll, M.

    2013-12-01

    The community using NASA Earth science observations in applications has grown significantly, with increasing sophistication to serve national interests. The National Research Council's Earth Science Decadal Survey report stated that the planning for applied and operational considerations in the missions should accompany the acquisition of new knowledge about Earth (NRC, 2007). This directive has made product applications at NASA an integral part of converting the data collected into actionable knowledge that can be used to inform policy. However, successfully bridging scientific research with operational decision making in different application areas requires looking into user data requirements and operational needs. This study was conducted to determine how users are incorporating NASA data into applications and operational processes. The approach included a review of published materials, direct interviews with mission representatives, and an online professional review, which was distributed to over 6000 individuals. We provide a complete description of the findings with definitions and explanations of what goes into measuring latency as well as how users and applications utilize NASA data products. We identified 3 classes of users: operational (need data in 3 hours or less), near real time (need data within a day of acquisition), and scientific users (need highest quality data, time independent). We also determined that most users with applications are interested in specific types of products that may come from multiple missions. These users will take the observations when they are available, however the observations may have additional applications value if they are available either by a certain time of day or within a period of time after acquisition. NASA has supported the need for access to low latency data on an ad-hoc basis and more substantively in stand-alone systems such as the MODIS Rapid Response system and more recently with LANCE. The increased level

  16. Change in convergence and accommodation after two weeks of eye exercises in typical young adults.

    Science.gov (United States)

    Horwood, Anna M; Toor, Sonia S; Riddell, Patricia M

    2014-04-01

    Although eye exercises appear to help heterophoria, convergence insufficiency, and intermittent strabismus, results can be confounded by placebo, practice, and encouragement effects. This study assessed objective changes in vergence and accommodation responses in naive young adults after a 2-week period of eye exercises under controlled conditions to determine the extent to which treatment effects occur over other factors. Asymptomatic young adults were randomly assigned to one of two no-treatment (control) groups or to one of six eye exercise groups: accommodation, vergence, both, convergence in excess of accommodation, accommodation in excess of convergence, and placebo. Subjects were tested and retested under identical conditions, except for the second control group, who were additionally encouraged. Objective accommodation and vergence were assessed to a range of targets moving in depth containing combinations of blur, disparity, and proximity/looming cues. A total of 156 subjects were included. Response gain improved more for less naturalistic targets where more improvement was possible. Convergence exercises improved vergence for near across all targets (P = 0.035). Mean accommodation changed similarly but nonsignificantly. No other treatment group differed significantly from the nonencouraged control group, whereas encouraging effort produced significantly increased vergence (P = 0.004) and accommodation (P = 0.005) gains in the second control group. True treatment effects were small, significantly better only after vergence exercises to a nonaccommodative target, and rarely related to the response they were designed to improve. Exercising accommodation without convergence made no difference to accommodation to cues containing detail. Additional effort improved objective responses the most. Copyright © 2014 American Association for Pediatric Ophthalmology and Strabismus. Published by Mosby, Inc. All rights reserved.

  17. Scalla: Structured Cluster Architecture for Low Latency Access

    Energy Technology Data Exchange (ETDEWEB)

    Hanushevsky, Andrew; Wang, Daniel L.; /SLAC

    2012-03-20

    Scalla is a distributed low-latency file access system that incorporates novel techniques that minimize latency and maximize scalability over a large distributed system with a distributed namespace. Scalla's techniques have shown to be effective in nearly a decade of service for the high-energy physics community using commodity hardware and interconnects. We describe the two components used in Scalla that are instrumental in its ability to provide low-latency, fault-tolerant name resolution and load distribution, and enable its use as a high-throughput, low-latency communication layer in the Qserv system, the Large Synoptic Survey Telescope's (LSST's) prototype astronomical query system. Scalla arguably exceeded its three main design objectives: low latency, scaling, and recoverability. In retrospect, these objectives were met using a simple but effective design. Low latency was met by uniformly using linear or constant time algorithms in all high-use paths, avoiding locks whenever possible, and using compact data structures to maximize the memory caching efficiency. Scaling was achieved by architecting the system as a 64-ary tree. Nodes can be added easily and as the number of nodes increases, search performance increases at an exponential rate. Recoverability is inherent in that no permanent state information is maintained and whatever state information is needed it can be quickly constructed or reconstructed in real time. This allows dynamic changes in a cluster of servers with little impact on over-all performance or usability. Today, Scalla is being deployed in environments and for uses that were never conceived in 2001. This speaks well for the systems adaptability but the underlying reason is that the system can meet its three fundamental objectives at the same time.

  18. Automatic latency equalization in VHDL-implemented complex pipelined systems

    Science.gov (United States)

    Zabołotny, Wojciech M.

    2016-09-01

    In the pipelined data processing systems it is very important to ensure that parallel paths delay data by the same number of clock cycles. If that condition is not met, the processing blocks receive data not properly aligned in time and produce incorrect results. Manual equalization of latencies is a tedious and error-prone work. This paper presents an automatic method of latency equalization in systems described in VHDL. The proposed method uses simulation to measure latencies and verify introduced correction. The solution is portable between different simulation and synthesis tools. The method does not increase the complexity of the synthesized design comparing to the solution based on manual latency adjustment. The example implementation of the proposed methodology together with a simple design demonstrating its use is available as an open source project under BSD license.

  19. Cancer Disparities

    Science.gov (United States)

    Basic information about cancer disparities in the U.S., factors that contribute to the disproportionate burden of cancer in some groups, and examples of disparities in incidence and mortality among certain populations.

  20. Health Disparities

    Science.gov (United States)

    ... Health and Health Disparities conduct transdisciplinary research involving social, behavioral, biological, and genetic research to improve knowledge of the causes of health disparities and devise effective methods of preventing, diagnosing, and treating disease and promoting ...

  1. Human embryonic stem cell lines model experimental human cytomegalovirus latency.

    Science.gov (United States)

    Penkert, Rhiannon R; Kalejta, Robert F

    2013-05-28

    Herpesviruses are highly successful pathogens that persist for the lifetime of their hosts primarily because of their ability to establish and maintain latent infections from which the virus is capable of productively reactivating. Human cytomegalovirus (HCMV), a betaherpesvirus, establishes latency in CD34(+) hematopoietic progenitor cells during natural infections in the body. Experimental infection of CD34(+) cells ex vivo has demonstrated that expression of the viral gene products that drive productive infection is silenced by an intrinsic immune defense mediated by Daxx and histone deacetylases through heterochromatinization of the viral genome during the establishment of latency. Additional mechanistic details about the establishment, let alone maintenance and reactivation, of HCMV latency remain scarce. This is partly due to the technical challenges of CD34(+) cell culture, most notably, the difficulty in preventing spontaneous differentiation that drives reactivation and renders them permissive for productive infection. Here we demonstrate that HCMV can establish, maintain, and reactivate in vitro from experimental latency in cultures of human embryonic stem cells (ESCs), for which spurious differentiation can be prevented or controlled. Furthermore, we show that known molecular aspects of HCMV latency are faithfully recapitulated in these cells. In total, we present ESCs as a novel, tractable model for studies of HCMV latency.

  2. Experimental demonstration of polar coded IM/DD optical OFDM for short reach system

    Science.gov (United States)

    Fang, Jiafei; Xiao, Shilin; Liu, Ling; Bi, Meihua; Zhang, Lu; Zhang, Yunhao; Hu, Weisheng

    2017-11-01

    In this paper, we propose a novel polar coded intensity modulation direct detection (IM/DD) optical orthogonal frequency division multiplexing (OFDM) system for short reach system. A method of evaluating the channel signal noise ratio (SNR) is proposed for soft-demodulation. The experimental results demonstrate that, compared to the conventional case, ∼9.5 dB net coding gain (NCG) at the bit error rate (BER) of 1E-3 can be achieved after 40-km standard single mode fiber (SSMF) transmission. Based on the experimental result, (512,256) polar code with low complexity and satisfactory BER performance meets the requirement of low latency in short reach system, which is a promising candidate for latency-stringent short reach optical system.

  3. Low-latency situational awareness for UxV platforms

    Science.gov (United States)

    Berends, David C.

    2012-06-01

    Providing high quality, low latency video from unmanned vehicles through bandwidth-limited communications channels remains a formidable challenge for modern vision system designers. SRI has developed a number of enabling technologies to address this, including the use of SWaP-optimized Systems-on-a-Chip which provide Multispectral Fusion and Contrast Enhancement as well as H.264 video compression. Further, the use of salience-based image prefiltering prior to image compression greatly reduces output video bandwidth by selectively blurring non-important scene regions. Combined with our customization of the VLC open source video viewer for low latency video decoding, SRI developed a prototype high performance, high quality vision system for UxV application in support of very demanding system latency requirements and user CONOPS.

  4. Integer-valued Lévy processes and low latency financial econometrics

    DEFF Research Database (Denmark)

    Barndorff-Nielsen, Ole; Pollard, David G.; Shephard, Neil

    Motivated by features of low latency data in financial econometrics we study in detail integervalued Lévy processes as the basis of price processes for high frequency econometrics. We propose using models built out of the difference of two subordinators. We apply these models in practice to low...... latency data for a variety of different types of futures contracts.futures markets, high frequency econometrics, low latency data, negative binomial, Skellam, tempered stable...

  5. Impact of wave propagation delay on latency in optical communication systems

    Science.gov (United States)

    Kawanishi, Tetsuya; Kanno, Atsushi; Yoshida, Yuki; Kitayama, Ken-ichi

    2012-12-01

    Latency is an important figure to describe performance of transmission systems for particular applications, such as data transfer for earthquake early warning, transaction for financial businesses, interactive services such as online games, etc. Latency consists of delay due to signal processing at nodes and transmitters, and of signal propagation delay due to propagation of electromagnetic waves. The lower limit of the latency in transmission systems using conventional single mode fibers (SMFs) depends on wave propagation speed in the SMFs which is slower than c. Photonic crystal fibers, holly fibers and large core fibers can have low effective refractive indices, and can transfer light faster than in SMFs. In free-space optical systems, signals propagate with the speed c, so that the latency could be smaller than in optical fibers. For example, LEO satellites would transmit data faster than optical submarine cables, when the transmission distance is longer than a few thousand kilometers. This paper will discuss combination of various transmission media to reduce negative impact of the latency, as well as applications of low-latency systems.

  6. Disparity and convergence: Chinese provincial government health expenditures.

    Science.gov (United States)

    Pan, Jay; Wang, Peng; Qin, Xuezheng; Zhang, Shufang

    2013-01-01

    The huge regional disparity in government health expenditures (GHE) is a major policy concern in China. This paper addresses whether provincial GHE converges in China from 1997 to 2009 using the economic convergence framework based on neoclassical economic growth theory. Our empirical investigation provides compelling evidence of long-term convergence in provincial GHE within China, but not in short-term. Policy implications of these empirical results are discussed.

  7. Disparity and convergence: Chinese provincial government health expenditures.

    Directory of Open Access Journals (Sweden)

    Jay Pan

    Full Text Available The huge regional disparity in government health expenditures (GHE is a major policy concern in China. This paper addresses whether provincial GHE converges in China from 1997 to 2009 using the economic convergence framework based on neoclassical economic growth theory. Our empirical investigation provides compelling evidence of long-term convergence in provincial GHE within China, but not in short-term. Policy implications of these empirical results are discussed.

  8. Statistical learning methods for aero-optic wavefront prediction and adaptive-optic latency compensation

    Science.gov (United States)

    Burns, W. Robert

    Since the early 1970's research in airborne laser systems has been the subject of continued interest. Airborne laser applications depend on being able to propagate a near diffraction-limited laser beam from an airborne platform. Turbulent air flowing over the aircraft produces density fluctuations through which the beam must propagate. Because the index of refraction of the air is directly related to the density, the turbulent flow imposes aberrations on the beam passing through it. This problem is referred to as Aero-Optics. Aero-Optics is recognized as a major technical issue that needs to be solved before airborne optical systems can become routinely fielded. This dissertation research specifically addresses an approach to mitigating the deleterious effects imposed on an airborne optical system by aero-optics. A promising technology is adaptive optics: a feedback control method that measures optical aberrations and imprints the conjugate aberrations onto an outgoing beam. The challenge is that it is a computationally-difficult problem, since aero-optic disturbances are on the order of kilohertz for practical applications. High control loop frequencies and high disturbance frequencies mean that adaptive-optic systems are sensitive to latency in sensors, mirrors, amplifiers, and computation. These latencies build up to result in a dramatic reduction in the system's effective bandwidth. This work presents two variations of an algorithm that uses model reduction and data-driven predictors to estimate the evolution of measured wavefronts over a short temporal horizon and thus compensate for feedback latency. The efficacy of the two methods are compared in this research, and evaluated against similar algorithms that have been previously developed. The best version achieved over 75% disturbance rejection in simulation in the most optically active flow region in the wake of a turret, considerably outperforming conventional approaches. The algorithm is shown to be

  9. Cumulative latency advance underlies fast visual processing in desynchronized brain state.

    Science.gov (United States)

    Wang, Xu-dong; Chen, Cheng; Zhang, Dinghong; Yao, Haishan

    2014-01-07

    Fast sensory processing is vital for the animal to efficiently respond to the changing environment. This is usually achieved when the animal is vigilant, as reflected by cortical desynchronization. However, the neural substrate for such fast processing remains unclear. Here, we report that neurons in rat primary visual cortex (V1) exhibited shorter response latency in the desynchronized state than in the synchronized state. In vivo whole-cell recording from the same V1 neurons undergoing the two states showed that both the resting and visually evoked conductances were higher in the desynchronized state. Such conductance increases of single V1 neurons shorten the response latency by elevating the membrane potential closer to the firing threshold and reducing the membrane time constant, but the effects only account for a small fraction of the observed latency advance. Simultaneous recordings in lateral geniculate nucleus (LGN) and V1 revealed that LGN neurons also exhibited latency advance, with a degree smaller than that of V1 neurons. Furthermore, latency advance in V1 increased across successive cortical layers. Thus, latency advance accumulates along various stages of the visual pathway, likely due to a global increase of membrane conductance in the desynchronized state. This cumulative effect may lead to a dramatic shortening of response latency for neurons in higher visual cortex and play a critical role in fast processing for vigilant animals.

  10. Construction and Evaluation of an Ultra Low Latency Frameless Renderer for VR.

    Science.gov (United States)

    Friston, Sebastian; Steed, Anthony; Tilbury, Simon; Gaydadjiev, Georgi

    2016-04-01

    Latency - the delay between a user's action and the response to this action - is known to be detrimental to virtual reality. Latency is typically considered to be a discrete value characterising a delay, constant in time and space - but this characterisation is incomplete. Latency changes across the display during scan-out, and how it does so is dependent on the rendering approach used. In this study, we present an ultra-low latency real-time ray-casting renderer for virtual reality, implemented on an FPGA. Our renderer has a latency of ~1 ms from 'tracker to pixel'. Its frameless nature means that the region of the display with the lowest latency immediately follows the scan-beam. This is in contrast to frame-based systems such as those using typical GPUs, for which the latency increases as scan-out proceeds. Using a series of high and low speed videos of our system in use, we confirm its latency of ~1 ms. We examine how the renderer performs when driving a traditional sequential scan-out display on a readily available HMO, the Oculus Rift OK2. We contrast this with an equivalent apparatus built using a GPU. Using captured human head motion and a set of image quality measures, we assess the ability of these systems to faithfully recreate the stimuli of an ideal virtual reality system - one with a zero latency tracker, renderer and display running at 1 kHz. Finally, we examine the results of these quality measures, and how each rendering approach is affected by velocity of movement and display persistence. We find that our system, with a lower average latency, can more faithfully draw what the ideal virtual reality system would. Further, we find that with low display persistence, the sensitivity to velocity of both systems is lowered, but that it is much lower for ours.

  11. Optimizing latency in Xilinx FPGA implementations of the GBT

    International Nuclear Information System (INIS)

    Muschter, S; Bohm, C; Baron, S; Soos, C; Cachemiche, J-P

    2010-01-01

    The GigaBit Transceiver (GBT) system has been developed to replace the Timing, Trigger and Control (TTC) system, currently used by LHC, as well as to provide data transmission between on-detector and off-detector components in future sLHC detectors. A VHDL version of the GBT-SERDES, designed for FPGAs, was released in March 2010 as a GBT-FPGA Starter Kit for future GBT users and for off-detector GBT implementation. This code was optimized for resource utilization, as the GBT protocol is very demanding. It was not, however, optimized for latency - which will be a critical parameter when used in the trigger path. The GBT-FPGA Starter Kit firmware was first analyzed in terms of latency by looking at the separate components of the VHDL version. Once the parts which contribute most to the latency were identified and modified, two possible optimizations were chosen, resulting in a latency reduced by a factor of three. The modifications were also analyzed in terms of logic utilization. The latency optimization results were compared with measurement results from a Virtex 6 ML605 development board equipped with a XC6VLX240T with speedgrade-1 and the package FF1156. Bit error rate tests were also performed to ensure an error free operation. The two final optimizations were analyzed for utilization and compared with the original code, distributed in the Starter Kit.

  12. Glomerular latency coding in artificial olfaction.

    Science.gov (United States)

    Yamani, Jaber Al; Boussaid, Farid; Bermak, Amine; Martinez, Dominique

    2011-01-01

    Sensory perception results from the way sensory information is subsequently transformed in the brain. Olfaction is a typical example in which odor representations undergo considerable changes as they pass from olfactory receptor neurons (ORNs) to second-order neurons. First, many ORNs expressing the same receptor protein yet presenting heterogeneous dose-response properties converge onto individually identifiable glomeruli. Second, onset latency of glomerular activation is believed to play a role in encoding odor quality and quantity in the context of fast information processing. Taking inspiration from the olfactory pathway, we designed a simple yet robust glomerular latency coding scheme for processing gas sensor data. The proposed bio-inspired approach was evaluated using an in-house SnO(2) sensor array. Glomerular convergence was achieved by noting the possible analogy between receptor protein expressed in ORNs and metal catalyst used across the fabricated gas sensor array. Ion implantation was another technique used to account both for sensor heterogeneity and enhanced sensitivity. The response of the gas sensor array was mapped into glomerular latency patterns, whose rank order is concentration-invariant. Gas recognition was achieved by simply looking for a "match" within a library of spatio-temporal spike fingerprints. Because of its simplicity, this approach enables the integration of sensing and processing onto a single-chip.

  13. HIV-1 Latency in Monocytes/Macrophages

    Directory of Open Access Journals (Sweden)

    Amit Kumar

    2014-04-01

    Full Text Available Human immunodeficiency virus type 1 (HIV-1 targets CD4+ T cells and cells of the monocyte/macrophage lineage. HIV pathogenesis is characterized by the depletion of T lymphocytes and by the presence of a population of cells in which latency has been established called the HIV-1 reservoir. Highly active antiretroviral therapy (HAART has significantly improved the life of HIV-1 infected patients. However, complete eradication of HIV-1 from infected individuals is not possible without targeting latent sources of infection. HIV-1 establishes latent infection in resting CD4+ T cells and findings indicate that latency can also be established in the cells of monocyte/macrophage lineage. Monocyte/macrophage lineage includes among others, monocytes, macrophages and brain resident macrophages. These cells are relatively more resistant to apoptosis induced by HIV-1, thus are important stable hideouts of the virus. Much effort has been made in the direction of eliminating HIV-1 resting CD4+ T-cell reservoirs. However, it is impossible to achieve a cure for HIV-1 without considering these neglected latent reservoirs, the cells of monocyte/macrophage lineage. In this review we will describe our current understanding of the mechanism of latency in monocyte/macrophage lineage and how such cells can be specifically eliminated from the infected host.

  14. Fault latency in the memory - An experimental study on VAX 11/780

    Science.gov (United States)

    Chillarege, Ram; Iyer, Ravishankar K.

    1986-01-01

    Fault latency is the time between the physical occurrence of a fault and its corruption of data, causing an error. The measure of this time is difficult to obtain because the time of occurrence of a fault and the exact moment of generation of an error are not known. This paper describes an experiment to accurately study the fault latency in the memory subsystem. The experiment employs real memory data from a VAX 11/780 at the University of Illinois. Fault latency distributions are generated for s-a-0 and s-a-1 permanent fault models. Results show that the mean fault latency of a s-a-0 fault is nearly 5 times that of the s-a-1 fault. Large variations in fault latency are found for different regions in memory. An analysis of a variance model to quantify the relative influence of various workload measures on the evaluated latency is also given.

  15. Distraction rate and latency: factors in the outcome of paediatric maxillary distraction.

    Science.gov (United States)

    Higuera, Stephen; Cole, Patrick; Stephenson, J B; Hollier, Larry

    2009-12-01

    absolute and may not be optimal for use in the paediatric maxilla. Our results demonstrate effective maxillary correction following application of a 24-h latency period coupled with rapid distraction at 2mm/day. Our success with a short latency period and more rapid device expanse may be a product of the significant vascularity and improved healing potential of the paediatric maxilla.

  16. Prophylactic transabdominal amnioinfusion in oligohydramnios for preterm premature rupture of membranes: increase of amniotic fluid index during latency period.

    Science.gov (United States)

    Garzetti, G G; Ciavattini, A; De Cristofaro, F; La Marca, N; Arduini, D

    1997-01-01

    This study was designed to: (i) evaluate the effect of amnioinfusion on the latency period in patients with oligohydramnios for preterm premature rupture of membranes, and (ii) to investigate the relationship between changes in the amniotic fluid index and fetal heart rate short-term variability by computerized Hewlett-Packard cardiotocography, longitudinally estimated before and after prophylactic amnioinfusion. All singleton pregnancies with prolonged premature rupture of membranes after 25 weeks of gestation and seen at the Institute of Obstetrics and Gynecology, University of Ancona (Italy), between January 1994 and June 1995 were included in the study. Transabdominal amnioinfusion with 150-350 ml warmed normal saline (25-50 ml/min) was performed at weekly intervals. Amniotic fluid volume was assessed ultrasonographically by means of the four-quadrant technique on a weekly basis before and after each amnioinfusion, as well as the short-term variability by a Hewlett-Packard computerized cardiotocographic system. 18 women were enrolled and underwent prophylactic transabdominal amnioinfusion at weekly intervals until delivery. Eighteen controls, who did not undergo prophylactic amnioinfusion, were recruited from our 1992-1993 series and included in the study. The median interval between premature rupture of membranes and delivery was 3.0 weeks (range 1-8 weeks), with an average delivery age of 33.0 weeks (range 27-36 weeks). The latency period was significantly longer in patients who underwent prophylactic amnioinfusion (mean +/- SD, 4.1 +/- 1.7 weeks) than in controls(1.7 +/- 1.0 weeks; p amnioinfusion. A direct relationship was observed between the amniotic fluid index and short-term variability (linear regression analysis r = 0.54, p = 0.04). The mean values of fetal movements recorded by computerized tomography during the 20 min of observation significantly increased after amnioinfusion in comparison with those before it (2.6 +/- 0.9 and 0.9 +/- 0

  17. The Effect of Elective Rotations on the Self-assessment Examination Results of Physical Medicine and Rehabilitation Residents: Implications for Minimizing Educational Resource Disparities in Taiwan.

    Science.gov (United States)

    Lien, I-Nan; Wu, Pei-Shen; Wang, Tyng-Guey; Chen, Wen-Shiang; Lew, Henry L

    2017-08-01

    The aims of the study were (1) to assess whether a knowledge disparity existed between physical medicine and rehabilitation residents from community hospitals versus those from medical centers, before the introduction of short-term elective training at the end of 2008 and (2), if such disparity existed, to determine whether 1-month short-term elective training was associated with minimizing such disparity, as reflected in the self-assessment examination scores. Self-assessment examination scores from 2007-2016 were analyzed in each of the following three topics: (a) cardiac rehabilitation, (b) pulmonary rehabilitation, and (c) orthotics. Student's t tests were used to identify score discrepancies between both groups. (1) At baseline (2007-2008), trainees from community hospitals scored lower in all three topics (P < 0.05). (2) After the short-term elective training, follow-up comparisons showed no differences in either cardiac or pulmonary rehabilitation for 2009-2016. Regarding orthotics, trainees from both groups showed no significant differences for 2009-2010 and 2011-2012. Interestingly, for 2013-2014 and 2015-2016, trainees from medical centers scored higher again, but only in orthotics. (1) In 2007-2008, a knowledge disparity existed between physical medicine and rehabilitation residents from community hospitals and medical centers in Taiwan. (2) Short-term elective training was associated with minimizing such disparity from 2009-2016, especially in cardiac and pulmonary rehabilitation.

  18. Optimizing latency in Xilinx FPGA implementations of the GBT

    CERN Document Server

    Muschter, S; Bohm, C; Cachemiche, J-P; Baron, S

    2010-01-01

    The GigaBit Transceiver (GBT) {[}1] system has been developed to replace the Timing, Trigger and Control (TTC) system {[}2], currently used by LHC, as well as to provide data transmission between on-detector and off-detector components in future sLHC detectors. A VHDL version of the GBT-SERDES, designed for FPGAs, was released in March 2010 as a GBT-FPGA Starter Kit for future GBT users and for off-detector GBT implementation {[}3]. This code was optimized for resource utilization {[}4], as the GBT protocol is very demanding. It was not, however, optimized for latency - which will be a critical parameter when used in the trigger path. The GBT-FPGA Starter Kit firmware was first analyzed in terms of latency by looking at the separate components of the VHDL version. Once the parts which contribute most to the latency were identified and modified, two possible optimizations were chosen, resulting in a latency reduced by a factor of three. The modifications were also analyzed in terms of logic utilization. The la...

  19. Estimating latency from inhibitory input

    Czech Academy of Sciences Publication Activity Database

    Leváková, Marie; Ditlevsen, S.; Lánský, Petr

    2014-01-01

    Roč. 108, č. 4 (2014), s. 475-493 ISSN 0340-1200 R&D Projects: GA ČR(CZ) GBP304/12/G069 Institutional support: RVO:67985823 Keywords : neuronal activity * latency * information coding * inhibition Subject RIV: ED - Physiology Impact factor: 1.713, year: 2014

  20. Evaluation of Ocular Accommodation, Convergence and Fusional Vergence Changes during Ramadan

    Directory of Open Access Journals (Sweden)

    Seyed Hosein Hoseini-Yazdi

    2013-07-01

    Full Text Available Purpose: There are a few researches regarding the effects of Islamic fasting on visual system. The aim of this study was to investigate the effects of Ramadan fasting on the amplitude of accommodation (AA, near point of convergence (NPC, positive and negative fusional vergences (PFV and NFV, respectively in visually healthy fasters. Methods: AA, NPC, PFV and NFV at far (6m and near (40cm were measured in 30 male students. Nutritional habits in a week before each examination visit were assessed with the Food Frequency Questionnaire (FFQ. Results: Mean age and fasting average experience were 23.9 and 10 years, respectively. AA and NPC showed significant changes (p<0.05 during Ramadan; but there was no significant difference before and after Ramadan in these parameters. NFV blur, break and recovery points at far significantly reduced in Ramadan than before (p=0.003, p=0.005, p=0.003, respectively with insignificant compensation after Ramadan. Results showed that there was no significant correlation between changes in diet pattern and AA, NPC and distant NFV variations (p<0.05. Conclusion: Some visual problems may be reported at far and near visual tasks during Ramadan; but most of the problems may be resolved after it. Some visual preparations may be needed for more effective visual activities during Ramadan; essentially for students with intensive visual tasks. Vision therapy may be suggested along with nutrient pattern improvement during Ramadan.

  1. Low-Latency Science Exploration of Planetary Bodies: How ISS Might Be Used as Part of a Low-Latency Analog Campaign for Human Exploration

    Science.gov (United States)

    Thronson, Harley; Valinia, Azita; Bleacher, Jacob; Eigenbrode, Jennifer; Garvin, Jim; Petro, Noah

    2014-01-01

    We suggest that the International Space Station be used to examine the application and validation of low-latency telepresence for surface exploration from space as an alternative, precursor, or potentially as an adjunct to astronaut "boots on the ground." To this end, controlled experiments that build upon and complement ground-based analog field studies will be critical for assessing the effects of different latencies (0 to 500 milliseconds), task complexity, and alternate forms of feedback to the operator. These experiments serve as an example of a pathfinder for NASA's roadmap of missions to Mars with low-latency telerobotic exploration as a precursor to astronaut's landing on the surface to conduct geological tasks.

  2. Optimizing latency in Xilinx FPGA implementations of the GBT

    Science.gov (United States)

    Muschter, S.; Baron, S.; Bohm, C.; Cachemiche, J.-P.; Soos, C.

    2010-12-01

    The GigaBit Transceiver (GBT) [1] system has been developed to replace the Timing, Trigger and Control (TTC) system [2], currently used by LHC, as well as to provide data transmission between on-detector and off-detector components in future sLHC detectors. A VHDL version of the GBT-SERDES, designed for FPGAs, was released in March 2010 as a GBT-FPGA Starter Kit for future GBT users and for off-detector GBT implementation [3]. This code was optimized for resource utilization [4], as the GBT protocol is very demanding. It was not, however, optimized for latency — which will be a critical parameter when used in the trigger path. The GBT-FPGA Starter Kit firmware was first analyzed in terms of latency by looking at the separate components of the VHDL version. Once the parts which contribute most to the latency were identified and modified, two possible optimizations were chosen, resulting in a latency reduced by a factor of three. The modifications were also analyzed in terms of logic utilization. The latency optimization results were compared with measurement results from a Virtex 6 ML605 development board [5] equipped with a XC6VLX240T with speedgrade-1 and the package FF1156. Bit error rate tests were also performed to ensure an error free operation. The two final optimizations were analyzed for utilization and compared with the original code, distributed in the Starter Kit.

  3. Small-molecule screening using a human primary cell model of HIV latency identifies compounds that reverse latency without cellular activation

    Science.gov (United States)

    Yang, Hung-Chih; Xing, Sifei; Shan, Liang; O’Connell, Karen; Dinoso, Jason; Shen, Anding; Zhou, Yan; Shrum, Cynthia K.; Han, Yefei; Liu, Jun O.; Zhang, Hao; Margolick, Joseph B.; Siliciano, Robert F.

    2009-01-01

    The development of highly active antiretroviral therapy (HAART) to treat individuals infected with HIV-1 has dramatically improved patient outcomes, but HAART still fails to cure the infection. The latent viral reservoir in resting CD4+ T cells is a major barrier to virus eradication. Elimination of this reservoir requires reactivation of the latent virus. However, strategies for reactivating HIV-1 through nonspecific T cell activation have clinically unacceptable toxicities. We describe here the development of what we believe to be a novel in vitro model of HIV-1 latency that we used to search for compounds that can reverse latency. Human primary CD4+ T cells were transduced with the prosurvival molecule Bcl-2, and the resulting cells were shown to recapitulate the quiescent state of resting CD4+ T cells in vivo. Using this model system, we screened small-molecule libraries and identified a compound that reactivated latent HIV-1 without inducing global T cell activation, 5-hydroxynaphthalene-1,4-dione (5HN). Unlike previously described latency-reversing agents, 5HN activated latent HIV-1 through ROS and NF-κB without affecting nuclear factor of activated T cells (NFAT) and PKC, demonstrating that TCR pathways can be dissected and utilized to purge latent virus. Our study expands the number of classes of latency-reversing therapeutics and demonstrates the utility of this in vitro model for finding strategies to eradicate HIV-1 infection. PMID:19805909

  4. Implications of sleep and energy drink use for health disparities

    Science.gov (United States)

    Grandner, Michael A; Knutson, Kristen L; Troxel, Wendy; Hale, Lauren; Jean-Louis, Girardin; Miller, Kathleen E

    2014-01-01

    The popularity of energy drinks has increased rapidly in the past decade. One of the main reasons people use energy drinks is to counteract effects of insufficient sleep or sleepiness. Risks associated with energy drink use, including those related to sleep loss, may be disproportionately borne by racial minorities and those of lower socioeconomic status. In this review, a brief introduction to the issue of health disparities is provided, population-level disparities and inequalities in sleep are described, and the social-ecological model of sleep and health is presented. Social and demographic patterns of energy drink use are then presented, followed by discussion of the potential ways in which energy drink use may contribute to health disparities, including the following: 1) effects of excessive caffeine in energy drinks, 2) effects of energy drinks as sugar-sweetened beverages, 3) association between energy drinks and risk-taking behaviors when mixed with alcohol, 4) association between energy drink use and short sleep duration, and 5) role of energy drinks in cardiometabolic disease. The review concludes with a research agenda of critical unanswered questions. PMID:25293540

  5. Engendering health disparities.

    Science.gov (United States)

    Spitzer, Denise L

    2005-01-01

    How is gender implicated in our exploration of health disparities in Canada? Set against the backdrop of federal government policy, this review paper examines the ways in which gender intersects with other health determinants to produce disparate health outcomes. An overview of salient issues including the impact of gender roles, environmental exposures, gender violence, workplace hazards, economic disparities, the costs of poverty, social marginalization and racism, aging, health conditions, interactions with health services, and health behaviours are considered. This review suggests health is detrimentally affected by gender roles and statuses as they intersect with economic disparities, cultural, sexual, physical and historical marginalization as well as the strains of domestic and paid labour. These conditions result in an unfair health burden borne in particular by women whose access to health determinants is--in various degrees--limited. While progress has certainly been made on some fronts, the persistence of health disparities among diverse populations of women and men suggests a postponement of the vision of a just society with health for all that was articulated in the Federal Plan on Gender Equality. Commitment, creativity and collaboration from stakeholders ranging from various levels of government, communities, academics, non-governmental agencies and health professionals will be required to reduce and eliminate health disparities between and among all members of our society.

  6. Genetic variants in RBFOX3 are associated with sleep latency

    NARCIS (Netherlands)

    N. Amin (Najaf); K.V. Allebrandt; A. van der Spek (Ashley); B. Müller-Myhsok (B.); K. Hek (Karin); M. Teder-Laving (Maris); C. Hayward (Caroline); T. Esko (Tõnu); J. van Mill; H. Mbarek; N.F. Watson (Nathaniel F); S.A. Melville (Scott); F.M. Del Greco (Fabiola); E.M. Byrne (Enda); E. Oole (Edwin); I. Kolcic (Ivana); T.H. Chen; D.S. Evans (Daniel); J. Coresh (Josef); N. Vogelzangs (Nicole); J. Karjalainen (Juha); G.A.H.M. Willemsen (Gonneke); S.A. Gharib (Sina); L. Zgaga (Lina); E. Mihailov (Evelin); K.L. Stone (Katie L); H. Campbell (Harry); R.W.W. Brouwer (Rutger); A. Demirkan (Ayşe); A.J. Isaacs (Aaron); Z. Dogas; K. Marciante (Kristin); S. Campbell (Susan); F. Borovecki (Fran); A.I. Luik (Annemarie I); M. Li (Man); J.J. Hottenga (Jouke Jan); J.E. Huffman (Jennifer); M.C.G.N. van den hout (Mirjam); S.R. Cummings (Steven R.); Y.S. Aulchenko (Yurii); P.R. Gehrman (Philip); A.G. Uitterlinden (André); H.E. Wichmann (Heinz Erich); M. Müller-Nurasyid (Martina); R.S.N. Fehrmann (Rudolf); G.W. Montgomery (Grant); A. Hofman (Albert); W.H.L. Kao (Wen Hong Linda); B.A. Oostra (Ben); A. Wright (Alan); J.M. Vink (Jacqueline); J.F. Wilson (James F); P.P. Pramstaller (Peter Paul); A.A. Hicks (Andrew); O. Polasek (Ozren); N.M. Punjabi (Naresh); S. Redline (Susan); B.M. Psaty (Bruce); A.C. Heath (Andrew C.); M. Merrow; G.J. Tranah (Gregory); D.J. Gottlieb (Daniel J); D.I. Boomsma (Dorret); N.G. Martin (Nicholas); I. Rudan (Igor); H.W. Tiemeier (Henning); W.F.J. van IJcken (Wilfred); B.W.J.H. Penninx; A. Metspalu (Andres); T. Meitinger (Thomas); L. Franke (Lude); T. Roenneberg; C.M. van Duijn (Cornelia)

    2016-01-01

    textabstractTime to fall asleep (sleep latency) is a major determinant of sleep quality. Chronic, long sleep latency is a major characteristic of sleep-onset insomnia and/or delayed sleep phase syndrome. In this study we aimed to discover common polymorphisms that contribute to the genetics of sleep

  7. CpG methylation controls reactivation of HIV from latency.

    Directory of Open Access Journals (Sweden)

    Jana Blazkova

    2009-08-01

    Full Text Available DNA methylation of retroviral promoters and enhancers localized in the provirus 5' long terminal repeat (LTR is considered to be a mechanism of transcriptional suppression that allows retroviruses to evade host immune responses and antiretroviral drugs. However, the role of DNA methylation in the control of HIV-1 latency has never been unambiguously demonstrated, in contrast to the apparent importance of transcriptional interference and chromatin structure, and has never been studied in HIV-1-infected patients. Here, we show in an in vitro model of reactivable latency and in a latent reservoir of HIV-1-infected patients that CpG methylation of the HIV-1 5' LTR is an additional epigenetic restriction mechanism, which controls resistance of latent HIV-1 to reactivation signals and thus determines the stability of the HIV-1 latency. CpG methylation acts as a late event during establishment of HIV-1 latency and is not required for the initial provirus silencing. Indeed, the latent reservoir of some aviremic patients contained high proportions of the non-methylated 5' LTR. The latency controlled solely by transcriptional interference and by chromatin-dependent mechanisms in the absence of significant promoter DNA methylation tends to be leaky and easily reactivable. In the latent reservoir of HIV-1-infected individuals without detectable plasma viremia, we found HIV-1 promoters and enhancers to be hypermethylated and resistant to reactivation, as opposed to the hypomethylated 5' LTR in viremic patients. However, even dense methylation of the HIV-1 5'LTR did not confer complete resistance to reactivation of latent HIV-1 with some histone deacetylase inhibitors, protein kinase C agonists, TNF-alpha, and their combinations with 5-aza-2deoxycytidine: the densely methylated HIV-1 promoter was most efficiently reactivated in virtual absence of T cell activation by suberoylanilide hydroxamic acid. Tight but incomplete control of HIV-1 latency by Cp

  8. Translating Research into Policy: Reducing Breast Cancer Disparities in Illinois

    Science.gov (United States)

    Dr. Carol Ferrans is internationally recognized for her work in disparities in health care and quality of life outcomes. She has a distinguished record of research that includes major grants funded by three institutes of the National Institutes of Health (National Cancer Institute, National Institute for Minority Health and Health Disparities, and National Institute for Nursing Research).    Dr. Ferrans’ work has been instrumental in reducing the disparity in breast cancer mortality Chicago, which at its peak was among the worst in the nation.  Efforts led by Dr. Ferrans and colleagues led directly to statewide legislation, to address the multifaceted causes of black/white disparity in deaths from breast cancer.  She was one of the founders of the Metropolitan Chicago Breast Cancer Task Force (MCBCTF), leading the team focusing on barriers to mammography screening, to identify reasons for the growing disparity in breast cancer mortality. Their findings (citing Ferrans’ research and others) and recommendations for action were translated directly into the Illinois Reducing Breast Cancer Disparities Act and two additional laws strengthening the Act.  These laws and other statewide efforts have improved access to screening and quality of mammography throughout the Illinois. In addition, Dr. Ferrans and her team identified cultural beliefs contributing to later stage diagnosis of breast cancer in African American and Latino women in Chicago, and most importantly, showed that these beliefs can be changed.  They reached more than 8,000 African American women in Chicago with a short film on DVD, which was effective in changing beliefs and promoting screening.  Her team’s published findings were cited by the American Cancer Society in their guidelines for breast cancer screening.  The Chicago black/white disparity in breast cancer deaths has decreased by 35% since the MCBCTF first released its report, according to data from the Illinois Department of Public

  9. On the influence of latency estimation on dynamic group communication using overlays

    Science.gov (United States)

    Vik, Knut-Helge; Griwodz, Carsten; Halvorsen, Pål

    2009-01-01

    Distributed interactive applications tend to have stringent latency requirements and some may have high bandwidth demands. Many of them have also very dynamic user groups for which all-to-all communication is needed. In online multiplayer games, for example, such groups are determined through region-of-interest management in the application. We have investigated a variety of group management approaches for overlay networks in earlier work and shown that several useful tree heuristics exist. However, these heuristics require full knowledge of all overlay link latencies. Since this is not scalable, we investigate the effects that latency estimation techqniues have ton the quality of overlay tree constructions. We do this by evaluating one example of our group management approaches in Planetlab and examing how latency estimation techqniues influence their quality. Specifically, we investigate how two well-known latency estimation techniques, Vivaldi and Netvigator, affect the quality of tree building.

  10. Cancer Disparities - Cancer Currents Blog

    Science.gov (United States)

    Blog posts on cancer health disparities research—including factors that influence disparities, disparities-related research efforts, and diversity in the cancer research workforce—from NCI Cancer Currents.

  11. Latency correction of event-related potentials between different experimental protocols

    Science.gov (United States)

    Iturrate, I.; Chavarriaga, R.; Montesano, L.; Minguez, J.; Millán, JdR

    2014-06-01

    Objective. A fundamental issue in EEG event-related potentials (ERPs) studies is the amount of data required to have an accurate ERP model. This also impacts the time required to train a classifier for a brain-computer interface (BCI). This issue is mainly due to the poor signal-to-noise ratio and the large fluctuations of the EEG caused by several sources of variability. One of these sources is directly related to the experimental protocol or application designed, and may affect the amplitude or latency of ERPs. This usually prevents BCI classifiers from generalizing among different experimental protocols. In this paper, we analyze the effect of the amplitude and the latency variations among different experimental protocols based on the same type of ERP. Approach. We present a method to analyze and compensate for the latency variations in BCI applications. The algorithm has been tested on two widely used ERPs (P300 and observation error potentials), in three experimental protocols in each case. We report the ERP analysis and single-trial classification. Main results. The results obtained show that the designed experimental protocols significantly affect the latency of the recorded potentials but not the amplitudes. Significance. These results show how the use of latency-corrected data can be used to generalize the BCIs, reducing the calibration time when facing a new experimental protocol.

  12. Ethnic and Racial Disparities in Education: Psychology's Role in Understanding and Reducing Disparities

    Science.gov (United States)

    Quintana, Stephen M.; Mahgoub, Lana

    2016-01-01

    We review the scope and sources of ethnic and racial disparities in education with a focus on the the implications of psychological theory and research for understanding and redressing these disparities. We identify 3 sources of ethnic and racial disparities including (a) social class differences, (b) differential treatment based on ethnic and…

  13. Towards Controlling Latency in Wireless Networks

    KAUST Repository

    Bouacida, Nader

    2017-01-01

    Wireless networks are undergoing an unprecedented revolution in the last decade. With the explosion of delay-sensitive applications in the Internet (i.e., online gaming and VoIP), latency becomes a major issue for the development of wireless

  14. The effect of monitor raster latency on VEPs, ERPs and Brain-Computer Interface performance.

    Science.gov (United States)

    Nagel, Sebastian; Dreher, Werner; Rosenstiel, Wolfgang; Spüler, Martin

    2018-02-01

    Visual neuroscience experiments and Brain-Computer Interface (BCI) control often require strict timings in a millisecond scale. As most experiments are performed using a personal computer (PC), the latencies that are introduced by the setup should be taken into account and be corrected. As a standard computer monitor uses a rastering to update each line of the image sequentially, this causes a monitor raster latency which depends on the position, on the monitor and the refresh rate. We technically measured the raster latencies of different monitors and present the effects on visual evoked potentials (VEPs) and event-related potentials (ERPs). Additionally we present a method for correcting the monitor raster latency and analyzed the performance difference of a code-modulated VEP BCI speller by correcting the latency. There are currently no other methods validating the effects of monitor raster latency on VEPs and ERPs. The timings of VEPs and ERPs are directly affected by the raster latency. Furthermore, correcting the raster latency resulted in a significant reduction of the target prediction error from 7.98% to 4.61% and also in a more reliable classification of targets by significantly increasing the distance between the most probable and the second most probable target by 18.23%. The monitor raster latency affects the timings of VEPs and ERPs, and correcting resulted in a significant error reduction of 42.23%. It is recommend to correct the raster latency for an increased BCI performance and methodical correctness. Copyright © 2017 Elsevier B.V. All rights reserved.

  15. Telemetry System Data Latency

    Science.gov (United States)

    2017-07-13

    latencies will be measured. DATS Network TM Antenna TM ReceiverMCS System IOPlex IOPlexIADS CDS IADS Client TM Transmitter Sensors Signal Conditioning...TIME Figure 1-2 Mission Control System (MCS) / Interactive Analysis and Display System (IADS) Overview IADS CDSIADS Client TELEMETRY SYSTEM DATA...Sim GPS Signal Combiner MCS system Oscilloscope IADS Client IADS CDS Figure 13-1 IADS Data Flow 13.2. Test Results The results of the data test at

  16. Arbitration in crossbar interconnect for low latency

    Science.gov (United States)

    Ohmacht, Martin; Sugavanam, Krishnan

    2013-02-05

    A system and method and computer program product for reducing the latency of signals communicated through a crossbar switch, the method including using at slave arbitration logic devices associated with Slave devices for which access is requested from one or more Master devices, two or more priority vector signals cycled among their use every clock cycle for selecting one of the requesting Master devices and updates the respective priority vector signal used every clock cycle. Similarly, each Master for which access is requested from one or more Slave devices, can have two or more priority vectors and can cycle among their use every clock cycle to further reduce latency and increase throughput performance via the crossbar.

  17. Mechanisms of Kaposi's Sarcoma-Associated Herpesvirus Latency and Reactivation

    Directory of Open Access Journals (Sweden)

    Fengchun Ye

    2011-01-01

    Full Text Available The life cycle of Kaposi's sarcoma-associated herpesvirus (KSHV consists of latent and lytic replication phases. During latent infection, only a limited number of KSHV genes are expressed. However, this phase of replication is essential for persistent infection, evasion of host immune response, and induction of KSHV-related malignancies. KSHV reactivation from latency produces a wide range of viral products and infectious virions. The resulting de novo infection and viral lytic products modulate diverse cellular pathways and stromal microenvironment, which promote the development of Kaposi's sarcoma (KS. The mechanisms controlling KSHV latency and reactivation are complex, involving both viral and host factors, and are modulated by diverse environmental factors. Here, we review the cellular and molecular basis of KSHV latency and reactivation with a focus on the most recent advancements in the field.

  18. An Optimized WSN Design for Latency-Critical Smart Grid Applications

    Directory of Open Access Journals (Sweden)

    Mounib Khanafer

    2017-01-01

    Full Text Available The growing popularity of the Internet of Things (IoT systems such as the smart grid, Body Area Networks (BANs, and the Intelligent Transportation System (ITS is driving Wireless Sensor Network (WSN systems to the limit in terms of abilities and performance. WSNs were initially designed for low power, low data rate, and latency-tolerant applications. However, this paradigm is changing because of the nature of the new applications. Therefore, instead of only focusing on power-efficient WSN design, researchers and industries are now developing Quality of Service (QoS protocols for WSNs. In addition to that, latency- and reliability-critical protocol designs are also becoming significantly important in WSNs. In this paper, we present an overview of some important smart grid latency-critical applications and highlight WSNs implementation challenges for these smart grid applications. Furthermore, we develop and evaluate two novel optimization models that solve for the optimum values of the end-to-end latency and power consumption in a clustered WSN given lower bounds on reliability and other network parameters.

  19. Unmasking the linear behaviour of slow motor adaptation to prolonged convergence.

    Science.gov (United States)

    Erkelens, Ian M; Thompson, Benjamin; Bobier, William R

    2016-06-01

    Adaptation to changing environmental demands is central to maintaining optimal motor system function. Current theories suggest that adaptation in both the skeletal-motor and oculomotor systems involves a combination of fast (reflexive) and slow (recalibration) mechanisms. Here we used the oculomotor vergence system as a model to investigate the mechanisms underlying slow motor adaptation. Unlike reaching with the upper limbs, vergence is less susceptible to changes in cognitive strategy that can affect the behaviour of motor adaptation. We tested the hypothesis that mechanisms of slow motor adaptation reflect early neural processing by assessing the linearity of adaptive responses over a large range of stimuli. Using varied disparity stimuli in conflict with accommodation, the slow adaptation of tonic vergence was found to exhibit a linear response whereby the rate (R(2)  = 0.85, P < 0.0001) and amplitude (R(2)  = 0.65, P < 0.0001) of the adaptive effects increased proportionally with stimulus amplitude. These results suggest that this slow adaptive mechanism is an early neural process, implying a fundamental physiological nature that is potentially dominated by subcortical and cerebellar substrates. © 2016 Federation of European Neuroscience Societies and John Wiley & Sons Ltd.

  20. Fundamental Tradeoffs among Reliability, Latency and Throughput in Cellular Networks

    DEFF Research Database (Denmark)

    Soret, Beatriz; Mogensen, Preben; Pedersen, Klaus I.

    2014-01-01

    We address the fundamental tradeoffs among latency, reliability and throughput in a cellular network. The most important elements influencing the KPIs in a 4G network are identified, and the inter-relationships among them is discussed. We use the effective bandwidth and the effective capacity......, in which latency and reliability will be two of the principal KPIs....

  1. Measuring the Latency of an Augmented Reality System for Robot-Assisted Minimally Invasive Surgery

    DEFF Research Database (Denmark)

    Jørgensen, Martin Kibsgaard; Kraus, Martin

    2017-01-01

    Minimal latency is important for augmented reality systems and teleoperation interfaces as even small increases in latency can affect user performance. Previously, we have developed an augmented reality system that can overlay stereoscopic video streams with computer graphics in order to improve....... The latency of the da Vinci S surgical system was on average 62 ms. None of the components of our overlay system (separately or combined) significantly affected the latency. However, the latency of the assistant's monitor increased by 14 ms. Passing the video streams through CPU or GPU memory increased...... visual communication in training for robot-assisted minimally invasive surgery with da Vinci surgical systems. To make sure that our augmented reality system provides the best possible user experience, we investigated the video latency of the da Vinci surgical system and how the components of our system...

  2. Analysis of methods to determine the latency of online movement adjustments

    NARCIS (Netherlands)

    Oostwoud Wijdenes, L.; Brenner, E.; Smeets, J.B.J.

    2014-01-01

    When studying online movement adjustments, one of the interesting parameters is their latency. We set out to compare three different methods of determining the latency: the threshold, confidence interval, and extrapolation methods. We simulated sets of movements with different movement times and

  3. Rein: Taming Tail Latency in Key-Value Stores via Multiget Scheduling

    KAUST Repository

    Reda, Waleed

    2017-04-17

    We tackle the problem of reducing tail latencies in distributed key-value stores, such as the popular Cassandra database.We focus on workloads of multiget requests, which batch together access to several data elements and parallelize read operations across the data store machines. We first analyze a production trace of a real system and quantify the skew due to multiget sizes, key popularity, and other factors. We then proceed to identify opportunities for reduction of tail latencies by recognizing the composition of aggregate requests and by carefully scheduling bottleneck operations that can otherwise create excessive queues. We design and implement a system called Rein, which reduces latency via inter-multiget scheduling using low overhead techniques. We extensively evaluate Rein via experiments in Amazon Web Services (AWS) and simulations. Our scheduling algorithms reduce the median, 95, and 99 percentile latencies by factors of 1.5, 1.5, and 1.9, respectively.

  4. Vertical binocular disparity is encoded implicitly within a model neuronal population tuned to horizontal disparity and orientation.

    Directory of Open Access Journals (Sweden)

    Jenny C A Read

    2010-04-01

    Full Text Available Primary visual cortex is often viewed as a "cyclopean retina", performing the initial encoding of binocular disparities between left and right images. Because the eyes are set apart horizontally in the head, binocular disparities are predominantly horizontal. Yet, especially in the visual periphery, a range of non-zero vertical disparities do occur and can influence perception. It has therefore been assumed that primary visual cortex must contain neurons tuned to a range of vertical disparities. Here, I show that this is not necessarily the case. Many disparity-selective neurons are most sensitive to changes in disparity orthogonal to their preferred orientation. That is, the disparity tuning surfaces, mapping their response to different two-dimensional (2D disparities, are elongated along the cell's preferred orientation. Because of this, even if a neuron's optimal 2D disparity has zero vertical component, the neuron will still respond best to a non-zero vertical disparity when probed with a sub-optimal horizontal disparity. This property can be used to decode 2D disparity, even allowing for realistic levels of neuronal noise. Even if all V1 neurons at a particular retinotopic location are tuned to the expected vertical disparity there (for example, zero at the fovea, the brain could still decode the magnitude and sign of departures from that expected value. This provides an intriguing counter-example to the common wisdom that, in order for a neuronal population to encode a quantity, its members must be tuned to a range of values of that quantity. It demonstrates that populations of disparity-selective neurons encode much richer information than previously appreciated. It suggests a possible strategy for the brain to extract rarely-occurring stimulus values, while concentrating neuronal resources on the most commonly-occurring situations.

  5. Conjunctions between motion and disparity are encoded with the same spatial resolution as disparity alone.

    Science.gov (United States)

    Allenmark, Fredrik; Read, Jenny C A

    2012-10-10

    Neurons in cortical area MT respond well to transparent streaming motion in distinct depth planes, such as caused by observer self-motion, but do not contain subregions excited by opposite directions of motion. We therefore predicted that spatial resolution for transparent motion/disparity conjunctions would be limited by the size of MT receptive fields, just as spatial resolution for disparity is limited by the much smaller receptive fields found in primary visual cortex, V1. We measured this using a novel "joint motion/disparity grating," on which human observers detected motion/disparity conjunctions in transparent random-dot patterns containing dots streaming in opposite directions on two depth planes. Surprisingly, observers showed the same spatial resolution for these as for pure disparity gratings. We estimate the limiting receptive field diameter at 11 arcmin, similar to V1 and much smaller than MT. Higher internal noise for detecting joint motion/disparity produces a slightly lower high-frequency cutoff of 2.5 cycles per degree (cpd) versus 3.3 cpd for disparity. This suggests that information on motion/disparity conjunctions is available in the population activity of V1 and that this information can be decoded for perception even when it is invisible to neurons in MT.

  6. The 5-HT2C receptor gene Cys23Ser polymorphism influences the intravaginal ejaculation latency time in Dutch Caucasian men with lifelong premature ejaculation

    NARCIS (Netherlands)

    Janssen, Paddy Kc; Schaik, Ron van; Olivier, Berend|info:eu-repo/dai/nl/073067199; Waldinger, Marcel D|info:eu-repo/dai/nl/163958564

    2014-01-01

    It has been postulated that the persistent short intravaginal ejaculation latency time (IELT) of men with lifelong premature ejaculation (LPE) is related to 5-hydroxytryptamine (HT)2C receptor functioning. The aim of this study was to investigate the relationship of Cys23Ser 5-HT2C receptor gene

  7. Latency transition of plasminogen activator inhibitor type 1 is evolutionarily conserved

    DEFF Research Database (Denmark)

    Jendroszek, Agnieszka; Sønnichsen, Malene; Chana Munoz, Andres

    2017-01-01

    relevance of latency transition. In order to study the origin of PAI-1 latency transition, we produced PAI-1 from Spiny dogfish shark (Squalus acanthias) and African lungfish (Protopterus sp.), which represent central species in the evolution of vertebrates. Although human PAI-1 and the non-mammalian PAI-1...

  8. Healthcare disparities in critical illness.

    Science.gov (United States)

    Soto, Graciela J; Martin, Greg S; Gong, Michelle Ng

    2013-12-01

    To summarize the current literature on racial and gender disparities in critical care and the mechanisms underlying these disparities in the course of acute critical illness. MEDLINE search on the published literature addressing racial, ethnic, or gender disparities in acute critical illness, such as sepsis, acute lung injury, pneumonia, venous thromboembolism, and cardiac arrest. Clinical studies that evaluated general critically ill patient populations in the United States as well as specific critical care conditions were reviewed with a focus on studies evaluating factors and contributors to health disparities. Study findings are presented according to their association with the prevalence, clinical presentation, management, and outcomes in acute critical illness. This review presents potential contributors for racial and gender disparities related to genetic susceptibility, comorbidities, preventive health services, socioeconomic factors, cultural differences, and access to care. The data are organized along the course of acute critical illness. The literature to date shows that disparities in critical care are most likely multifactorial involving individual, community, and hospital-level factors at several points in the continuum of acute critical illness. The data presented identify potential targets as interventions to reduce disparities in critical care and future avenues for research.

  9. Naturalistic depth perception and binocular vision

    OpenAIRE

    Maiello, G.

    2017-01-01

    Humans continuously move both their eyes to redirect their foveae to objects at new depths. To correctly execute these complex combinations of saccades, vergence eye movements and accommodation changes, the visual system makes use of multiple sources of depth information, including binocular disparity and defocus. Furthermore, during development, both fine-tuning of oculomotor control as well as correct eye growth are likely driven by complex interactions between eye movements, accommodation,...

  10. What Are Cancer Disparities?

    Science.gov (United States)

    This infographic shows the factors associated with cancer disparities, examples of how the cancer burden differs across certain population groups, and NCI actions to understand and reduce cancer disparities.

  11. Latency requirements for head-worn display S/EVS applications

    Science.gov (United States)

    Bailey, Randall E.; Arthur, Jarvis J., III; Williams, Steven P.

    2004-08-01

    NASA's Aviation Safety Program, Synthetic Vision Systems Project is conducting research in advanced flight deck concepts, such as Synthetic/Enhanced Vision Systems (S/EVS), for commercial and business aircraft. An emerging thrust in this activity is the development of spatially-integrated, large field-of-regard information display systems. Head-worn or helmet-mounted display systems are being proposed as one method in which to meet this objective. System delays or latencies inherent to spatially-integrated, head-worn displays critically influence the display utility, usability, and acceptability. Research results from three different, yet similar technical areas - flight control, flight simulation, and virtual reality - are collectively assembled in this paper to create a global perspective of delay or latency effects in head-worn or helmet-mounted display systems. Consistent definitions and measurement techniques are proposed herein for universal application and latency requirements for Head-Worn Display S/EVS applications are drafted. Future research areas are defined.

  12. A low-latency pipeline for GRB light curve and spectrum using Fermi/GBM near real-time data

    Science.gov (United States)

    Zhao, Yi; Zhang, Bin-Bin; Xiong, Shao-Lin; Long, Xi; Zhang, Qiang; Song, Li-Ming; Sun, Jian-Chao; Wang, Yuan-Hao; Li, Han-Cheng; Bu, Qing-Cui; Feng, Min-Zi; Li, Zheng-Heng; Wen, Xing; Wu, Bo-Bing; Zhang, Lai-Yu; Zhang, Yong-Jie; Zhang, Shuang-Nan; Shao, Jian-Xiong

    2018-05-01

    Rapid response and short time latency are very important for Time Domain Astronomy, such as the observations of Gamma-ray Bursts (GRBs) and electromagnetic (EM) counterparts of gravitational waves (GWs). Based on near real-time Fermi/GBM data, we developed a low-latency pipeline to automatically calculate the temporal and spectral properties of GRBs. With this pipeline, some important parameters can be obtained, such as T 90 and fluence, within ∼ 20 min after the GRB trigger. For ∼ 90% of GRBs, T 90 and fluence are consistent with the GBM catalog results within 2σ errors. This pipeline has been used by the Gamma-ray Bursts Polarimeter (POLAR) and the Insight Hard X-ray Modulation Telescope (Insight-HXMT) to follow up the bursts of interest. For GRB 170817A, the first EM counterpart of GW events detected by Fermi/GBM and INTEGRAL/SPI-ACS, the pipeline gave T 90 and spectral information 21 min after the GBM trigger, providing important information for POLAR and Insight-HXMT observations.

  13. Latency and Jitter Analysis for IEEE 802.11e Wireless LANs

    Directory of Open Access Journals (Sweden)

    Sungkwan Youm

    2013-01-01

    Full Text Available This paper presents a numerical analysis of latency and jitter for IEEE 802.11e wireless local area networks (WLANs in a saturation condition, by using a Markov model. We use this model to explicate how the enhanced distributed coordination function (EDCF differentiates classes of service and to characterize the probability distribution of the medium access control (MAC layer packet latency and jitter, on which the quality of the voice over Internet protocol (VoIP calls is dependent. From the proposed analytic model, we can estimate the available number of nodes determining the system performance, in order to satisfy user demands on the latency and jitter.

  14. Using Arduino microcontroller boards to measure response latencies.

    Science.gov (United States)

    Schubert, Thomas W; D'Ausilio, Alessandro; Canto, Rosario

    2013-12-01

    Latencies of buttonpresses are a staple of cognitive science paradigms. Often keyboards are employed to collect buttonpresses, but their imprecision and variability decreases test power and increases the risk of false positives. Response boxes and data acquisition cards are precise, but expensive and inflexible, alternatives. We propose using open-source Arduino microcontroller boards as an inexpensive and flexible alternative. These boards connect to standard experimental software using a USB connection and a virtual serial port, or by emulating a keyboard. In our solution, an Arduino measures response latencies after being signaled the start of a trial, and communicates the latency and response back to the PC over a USB connection. We demonstrated the reliability, robustness, and precision of this communication in six studies. Test measures confirmed that the error added to the measurement had an SD of less than 1 ms. Alternatively, emulation of a keyboard results in similarly precise measurement. The Arduino performs as well as a serial response box, and better than a keyboard. In addition, our setup allows for the flexible integration of other sensors, and even actuators, to extend the cognitive science toolbox.

  15. Iodine intake not radiation is the probable major influence on the morphology, aggressiveness and latency of papillary thyroid carcinomas (PTC)

    International Nuclear Information System (INIS)

    Williams, Dill; Vowler, Sarah; Bogdanova, Tania; Tronko, Nikol; Ito, Masah; Livolsi, Virg; Thomas, Gerry; Demidchik, Evg

    2005-01-01

    Full text: This study set out to investigate whether radiation induced thyroid cancers differ in morphology and aggressiveness from non radiation induced cancers, and whether other factors such as iodine intake are important. Chernobyl-related thyroid carcinomas, almost all PTCs, are reportedly typically morphologically solid, RET-PTC3 positive, and aggressive. We have studied 152 PTCs, 84 Chernobyl related (Chernobyl Tumour Bank), 23 unexposed children from the same area, and 45 from other countries. We quantified morphological changes and invasion, and found no significant differences between age-matched radiation-exposed and unexposed groups from the Chernobyl regions (papillary differentiation 34.3 v 35.2%, invasion 62 v 65 %). Age-matched tumours from Japan, a country with high dietary iodine, showed significantly more well-differentiated papillary architecture (80.8 v 43.3%, p<0.0001) and significantly less invasion (30 v 57 %, p<0.01) than tumours from Chernobyl regions. PTCs from England and Wales, iodine intake intermediate between Japan and the iodine deficient Chernobyl regions, showed intermediate features. We and others have shown that papillary architecture correlates with RET-PTC1 and solid morphology with RET-PTC3; the proportion of RET-PTC3 positive tumours has declined with increasing latency. We have also previously shown that solid morphology in Chernobyl-related PTCs correlates with short latency irrespective of age at exposure. Conclusion: We conclude that in the 19 years since the Chernobyl accident the radiation and non radiation-induced induced papillary carcinomas from the same areas do not differ in morphology and aggressiveness but both differ significantly from tumours from an iodine rich country. We suggest that these features and the surprisingly short latency after Chernobyl compared to other radiation incidents are influenced by the low dietary iodine intake. (author)

  16. The moral problem of health disparities.

    Science.gov (United States)

    Jones, Cynthia M

    2010-04-01

    Health disparities exist along lines of race/ethnicity and socioeconomic class in US society. I argue that we should work to eliminate these health disparities because their existence is a moral wrong that needs to be addressed. Health disparities are morally wrong because they exemplify historical injustices. Contractarian ethics, Kantian ethics, and utilitarian ethics all provide theoretical justification for viewing health disparities as a moral wrong, as do several ethical principles of primary importance in bioethics. The moral consequences of health disparities are also troubling and further support the claim that these disparities are a moral wrong. The Universal Declaration of Human Rights provides additional support that health disparities are a moral wrong, as does an analogy with the generally accepted duty to provide equal access to education. In this article, I also consider and respond to 3 objections to my thesis.

  17. The determinants of spoken and written picture naming latencies.

    Science.gov (United States)

    Bonin, Patrick; Chalard, Marylène; Méot, Alain; Fayol, Michel

    2002-02-01

    The influence of nine variables on the latencies to write down or to speak aloud the names of pictures taken from Snodgrass and Vanderwart (1980) was investigated in French adults. The major determinants of both written and spoken picture naming latencies were image variability, image agreement and age of acquisition. To a lesser extent, name agreement was also found to have an impact in both production modes. The implications of the findings for theoretical views of both spoken and written picture naming are discussed.

  18. Targeting HIV latency: pharmacologic strategies toward eradication

    Science.gov (United States)

    Xing, Sifei; Siliciano, Robert F.

    2013-01-01

    The latent reservoir for HIV-1 in resting CD4+ T cells remains a major barrier to HIV-1 eradication, even though highly active antiretroviral therapy (HAART) can successfully reduce plasma HIV-1 levels to below the detection limit of clinical assays and reverse disease progression. Proposed eradication strategies involve reactivation of this latent reservoir. Multiple mechanisms are believed to be involved in maintaining HIV-1 latency, mostly through suppression of transcription. These include cytoplasmic sequestration of host transcription factors and epigenetic modifications such as histone deacetylation, histone methylation and DNA methylation. Therefore, strategies targeting these mechanisms have been explored for reactivation of the latent reservoir. In this review, we discuss current pharmacological approaches toward eradication, focusing on small molecule latency-reversing agents, their mechanisms, advantages and limitations. PMID:23270785

  19. Mapping Medicare Disparities Tool

    Data.gov (United States)

    U.S. Department of Health & Human Services — The CMS Office of Minority Health has designed an interactive map, the Mapping Medicare Disparities Tool, to identify areas of disparities between subgroups of...

  20. Distance stereotest using a 3-dimensional monitor for adult subjects.

    Science.gov (United States)

    Kim, Jongshin; Yang, Hee Kyung; Kim, Youngmin; Lee, Byoungho; Hwang, Jeong-Min

    2011-06-01

    To evaluate the validity and test-retest reliability of a contour-based 3-dimensional (3-D) monitor distance stereotest (distance 3-D stereotest) and to measure the maximum horizontal disparity that can be fused with disparity vergence for determining the largest measurable disparity of true stereopsis. Observational case series. Sixty-four normal adult subjects (age range, 23 to 39 years) were recruited. Contour-based circles (crossed disparity, 5000 to 20 seconds of arc; Microsoft Visual Studio C(++) 6.0; Microsoft, Inc, Seattle, Washington, USA) were generated on a 3-D monitor (46-inch stereoscopic display) using polarization glasses and were presented to subjects with normal binocularity at 3 m. While the position of the stimulus changed among 4 possible locations, the subjects were instructed to press the corresponding position of the stimulus on a keypad. The results with the new distance 3-D stereotest were compared with those from the distance Randot stereotest. The results of the distance 3-D stereotest and the distance Randot stereotests were identical in 64% and within 1 disparity level in 97% of normal adults. Scores obtained with the 2 tests showed a statistically significant correlation (r = 0.324, P = .009). The half-width of the 95% limit of agreement was 0.47 log seconds of arc (1.55 octaves) using the distance 3-D stereotest--similar to or better than that obtained with conventional distance stereotests. The maximum binocular disparity that can be fused with vergence was 1828 ± 794 seconds of arc (range, 4000 to 500). The distance 3-D stereotest showed good concordance with the distance Randot stereotest and relatively good test-retest reliability, supporting the validity of the distance 3-D stereotest. The normative data set obtained from the present study can serve as a useful reference for quantitative assessment of a wide range of binocular sensory abnormalities. Copyright © 2011 Elsevier Inc. All rights reserved.

  1. Detecting concealed information in less than a second: response latency-based measures

    NARCIS (Netherlands)

    Verschuere, B.; de Houwer, J.; Verschuere, B.; Ben-Shakhar, G.; Meijer, E.

    2011-01-01

    Concealed information can be accurately assessed with physiological measures. To overcome the practical limitations of physiological measures, an assessment using response latencies has been proposed. At first sight, research findings on response latency based concealed information tests seem

  2. The Wnt Signaling Pathway Is Differentially Expressed during the Bovine Herpesvirus 1 Latency-Reactivation Cycle: Evidence That Two Protein Kinases Associated with Neuronal Survival, Akt3 and BMPR2, Are Expressed at Higher Levels during Latency.

    Science.gov (United States)

    Workman, Aspen; Zhu, Liqian; Keel, Brittney N; Smith, Timothy P L; Jones, Clinton

    2018-04-01

    Sensory neurons in trigeminal ganglia (TG) of calves latently infected with bovine herpesvirus 1 (BoHV-1) abundantly express latency-related (LR) gene products, including a protein (ORF2) and two micro-RNAs. Recent studies in mouse neuroblastoma cells (Neuro-2A) demonstrated ORF2 interacts with β-catenin and a β-catenin coactivator, high-mobility group AT-hook 1 (HMGA1) protein, which correlates with increased β-catenin-dependent transcription and cell survival. β-Catenin and HMGA1 are readily detected in a subset of latently infected TG neurons but not TG neurons from uninfected calves or reactivation from latency. Consequently, we hypothesized that the Wnt/β-catenin signaling pathway is differentially expressed during the latency and reactivation cycle and an active Wnt pathway promotes latency. RNA-sequencing studies revealed that 102 genes associated with the Wnt/β-catenin signaling pathway were differentially expressed in TG during the latency-reactivation cycle in calves. Wnt agonists were generally expressed at higher levels during latency, but these levels decreased during dexamethasone-induced reactivation. The Wnt agonist bone morphogenetic protein receptor 2 (BMPR2) was intriguing because it encodes a serine/threonine receptor kinase that promotes neuronal differentiation and inhibits cell death. Another differentially expressed gene encodes a protein kinase (Akt3), which is significant because Akt activity enhances cell survival and is linked to herpes simplex virus 1 latency and neuronal survival. Additional studies demonstrated ORF2 increased Akt3 steady-state protein levels and interacted with Akt3 in transfected Neuro-2A cells, which correlated with Akt3 activation. Conversely, expression of Wnt antagonists increased during reactivation from latency. Collectively, these studies suggest Wnt signaling cooperates with LR gene products, in particular ORF2, to promote latency. IMPORTANCE Lifelong BoHV-1 latency primarily occurs in sensory neurons

  3. Comparison of middle latency responses in presbycusis patients with two different speech recognition scores.

    Science.gov (United States)

    Kirkim, Gunay; Madanoglu, Nevma; Akdas, Ferda; Serbetcioglu, M Bulent

    2007-12-01

    The purpose of this study is to evaluate whether the middle latency responses (MLR) can be used for an objective differentiation of patients with presbycusis having relatively good (Group I) and relatively poor speech recognition scores (Group II). All the participants of these groups had high frequency down-sloping hearing loss with an average of 26-60 dB HL. Data were collected from two described study groups and a control group, using pure tone audiometry, monosyllabic phonetically balanced word and synthetic sentence identification, as well as MLR. The study groups were compared with the control group. When patients in Group I were compared with the control group, only ipsilateral Na latency of middle latency evoked response was statistically significant in the right ear whereas ipsilateral Na latency in the right ear, ipsilateral and contralateral Na latency in the left ear of the patients in Group II were statistically significant. Thus, as an objective complementary tool for the evaluation of the speech perception ability of the patients with presbycusis, Na latency of MLR may be used in combination with the speech discrimination tests.

  4. On the frequency dependence of the otoacoustic emission latency in hypoacoustic and normal ears

    Science.gov (United States)

    Sisto, R.; Moleti, A.

    2002-01-01

    Experimental measurements of the otoacoustic emission (OAE) latency of adult subjects have been obtained, as a function of frequency, by means of wavelet time-frequency analysis based on the iterative application of filter banks. The results are in agreement with previous OAE latency measurements by Tognola et al. [Hear. Res. 106, 112-122 (1997)], as regards both the latency values and the frequency dependence, and seem to be incompatible with the steep 1/f law that is predicted by scale-invariant full cochlear models. The latency-frequency relationship has been best fitted to a linear function of the cochlear physical distance, using the Greenwood map, and to an exponential function of the cochlear distance, for comparison with derived band ABR latency measurements. Two sets of ears [94 audiometrically normal and 42 impaired with high-frequency (f>3 kHz) hearing loss] have been separately analyzed. Significantly larger average latencies were found in the impaired ears in the mid-frequency range. Theoretical implications of these findings on the transmission of the traveling wave are discussed.

  5. A template-free approach for determining the latency of single events of auditory evoked M100

    Energy Technology Data Exchange (ETDEWEB)

    Burghoff, M [Physikalisch-Technische Bundesanstalt (PTB), Berlin (Germany); Link, A [Physikalisch-Technische Bundesanstalt (PTB), Berlin (Germany); Salajegheh, A [Cognitive Neuroscience of Language Laboratory, University of Maryland College Park, MD (United States); Elster, C [Physikalisch-Technische Bundesanstalt (PTB), Berlin (Germany); Poeppel, D [Cognitive Neuroscience of Language Laboratory, University of Maryland College Park, MD (United States); Trahms, L [Physikalisch-Technische Bundesanstalt (PTB), Berlin (Germany)

    2005-02-07

    The phase of the complex output of a narrow band Gaussian filter is taken to define the latency of the auditory evoked response M100 recorded by magnetoencephalography. It is demonstrated that this definition is consistent with the conventional peak latency. Moreover, it provides a tool for reducing the number of averages needed for a reliable estimation of the latency. Single-event latencies obtained by this procedure can be used to improve the signal quality of the conventional average by latency adjusted averaging. (note)

  6. Ocular herpes simplex virus: how are latency, reactivation, recurrent disease and therapy interrelated?

    Science.gov (United States)

    Al-Dujaili, Lena J; Clerkin, Patrick P; Clement, Christian; McFerrin, Harris E; Bhattacharjee, Partha S; Varnell, Emily D; Kaufman, Herbert E; Hill, James M

    2011-08-01

    Most humans are infected with herpes simplex virus (HSV) type 1 in early childhood and remain latently infected throughout life. While most individuals have mild or no symptoms, some will develop destructive HSV keratitis. Ocular infection with HSV-1 and its associated sequelae account for the majority of corneal blindness in industrialized nations. Neuronal latency in the peripheral ganglia is established when transcription of the viral genome is repressed (silenced) except for the latency-associated transcripts and microRNAs. The functions of latency-associated transcripts have been investigated since 1987. Roles have been suggested relating to reactivation, establishment of latency, neuronal protection, antiapoptosis, apoptosis, virulence and asymptomatic shedding. Here, we review HSV-1 latent infections, reactivation, recurrent disease and antiviral therapies for the ocular HSV diseases.

  7. Disparity changes in 370 Ma Devonian fossils: the signature of ecological dynamics?

    Science.gov (United States)

    Girard, Catherine; Renaud, Sabrina

    2012-01-01

    Early periods in Earth's history have seen a progressive increase in complexity of the ecosystems, but also dramatic crises decimating the biosphere. Such patterns are usually considered as large-scale changes among supra-specific groups, including morphological novelties, radiation, and extinctions. Nevertheless, in the same time, each species evolved by the way of micro-evolutionary processes, extended over millions of years into the evolution of lineages. How these two evolutionary scales interacted is a challenging issue because this requires bridging a gap between scales of observation and processes. The present study aims at transferring a typical macro-evolutionary approach, namely disparity analysis, to the study of fine-scale evolutionary variations in order to decipher what processes actually drove the dynamics of diversity at a micro-evolutionary level. The Late Frasnian to Late Famennian period was selected because it is punctuated by two major macro-evolutionary crises, as well as a progressive diversification of marine ecosystem. Disparity was estimated through this period on conodonts, tooth-like fossil remains of small eel-like predators that were part of the nektonic fauna. The study was focused on the emblematic genus of the period, Palmatolepis. Strikingly, both crises affected an already impoverished Palmatolepis disparity, increasing risks of random extinction. The major disparity signal rather emerged as a cycle of increase and decrease in disparity during the inter-crises period. The diversification shortly followed the first crisis and might correspond to an opportunistic occupation of empty ecological niche. The subsequent oriented shrinking in the morphospace occupation suggests that the ecological space available to Palmatolepis decreased through time, due to a combination of factors: deteriorating climate, expansion of competitors and predators. Disparity changes of Palmatolepis thus reflect changes in the structure of the ecological

  8. Disparity changes in 370 Ma Devonian fossils: the signature of ecological dynamics?

    Directory of Open Access Journals (Sweden)

    Catherine Girard

    Full Text Available Early periods in Earth's history have seen a progressive increase in complexity of the ecosystems, but also dramatic crises decimating the biosphere. Such patterns are usually considered as large-scale changes among supra-specific groups, including morphological novelties, radiation, and extinctions. Nevertheless, in the same time, each species evolved by the way of micro-evolutionary processes, extended over millions of years into the evolution of lineages. How these two evolutionary scales interacted is a challenging issue because this requires bridging a gap between scales of observation and processes. The present study aims at transferring a typical macro-evolutionary approach, namely disparity analysis, to the study of fine-scale evolutionary variations in order to decipher what processes actually drove the dynamics of diversity at a micro-evolutionary level. The Late Frasnian to Late Famennian period was selected because it is punctuated by two major macro-evolutionary crises, as well as a progressive diversification of marine ecosystem. Disparity was estimated through this period on conodonts, tooth-like fossil remains of small eel-like predators that were part of the nektonic fauna. The study was focused on the emblematic genus of the period, Palmatolepis. Strikingly, both crises affected an already impoverished Palmatolepis disparity, increasing risks of random extinction. The major disparity signal rather emerged as a cycle of increase and decrease in disparity during the inter-crises period. The diversification shortly followed the first crisis and might correspond to an opportunistic occupation of empty ecological niche. The subsequent oriented shrinking in the morphospace occupation suggests that the ecological space available to Palmatolepis decreased through time, due to a combination of factors: deteriorating climate, expansion of competitors and predators. Disparity changes of Palmatolepis thus reflect changes in the structure

  9. PERFORMANCE AND DEVELOPMENT LEVEL - COMPARATIVE ANALYSIS OF DISPARITIES AMONG REGIONS OF DEVELOPMENT AND MACRO-REGIONS IN ROMANIA

    Directory of Open Access Journals (Sweden)

    MARIA OŢIL

    2015-03-01

    Full Text Available The major challenge of the regional policies is to mitigate the social and economic disparities between different territories and regions. The immediate reality shows that this is a problem which is neither simple nor for short term. For Romania, which has large lags behind compared to the economically developed countries, the intense mobilization of internal and external factors of economic growth in order to reduce and eliminate disparities compared to other countries, is a definite necessity, a regularity resulting from regional and national interests in terms of its finality - the welfare of society. The economic crisis has increased regional disparities in the European Union countries, these especially affecting the countries which are less economically efficient. The present research aims at accomplishing a comparative analysis regarding disparities among regions of development and macro-regions of Romania in order to assess the performance of the productive sector, of the structural types of economies and of their level of development.

  10. The utility of a 5(th) nap in multiple sleep latency test.

    Science.gov (United States)

    Muza, Rexford; Lykouras, Dimosthenis; Rees, Kate

    2016-02-01

    This is the first study that aimed to look specifically at the utility of the 5(th) nap in the multiple sleep latency test (MSLT), a test used to assist in the diagnosis of narcolepsy. Data was retrospectively collected from the Sleep Disorders Centre of a Tertiary Hospital on patients that had a 5(th) nap during their MSLT from the 08(th) November 2011 to 12(th) November 2014. Fifty-three patients had a 5(th) nap performed out of 378 MSLT studies. In 16% of cases a diagnosis of narcolepsy was given directly due to the inclusion of the 5(th) nap on the MSLT. Here a 5(th) nap allowed diagnostic criteria of mean sleep latency 2 SOREMPS to be met. In 53% of cases the mean sleep latency increased due to 5(th) nap inclusion; the mean sleep latency of the first four naps was 5.6 vs. 6.7 after inclusion of the 5(th) nap. The 5(th) nap is not often performed within the MSLT studies. Our study shows that only a few patients may benefit from a 5(th) nap opportunity which also led to increase of the mean sleep latency at the expense of extra time, cost, labour and increased patient anxiety.

  11. Passive adaptation to stress in adulthood after short-term social instability stress during adolescence in mice.

    Science.gov (United States)

    de Lima, A P N; Massoco, C O

    2017-05-01

    This study reports that short-term social instability stress (SIS) in adolescence increases passive-coping in adulthood in male mice. Short-term SIS decreased the latency of immobility and increased the frequency and time of immobility in tail suspension test. These findings support the hypothesis that adolescent stress can induce a passive adaptation to stress in adulthood, even if it is a short period of stress.

  12. A review of the methods for neuronal response latency estimation

    DEFF Research Database (Denmark)

    Levakovaa, Marie; Tamborrino, Massimiliano; Ditlevsen, Susanne

    2015-01-01

    Neuronal response latency is usually vaguely defined as the delay between the stimulus onset and the beginning of the response. It contains important information for the understanding of the temporal code. For this reason, the detection of the response latency has been extensively studied in the ...... by the stimulation using interspike intervals and spike times. The aim of this paper is to present a review of the main techniques proposed in both classes, highlighting their advantages and shortcomings....

  13. Relation between derived-band auditory brainstem response latencies and behavioral frequency selectivity

    DEFF Research Database (Denmark)

    Strelcyk, Olaf; Christoforidis, Dimitrios; Dau, Torsten

    2009-01-01

    response times. For the same listeners, auditory-filter bandwidths at 2 kHz were estimated using a behavioral notched-noise masking paradigm. Generally, shorter derived-band latencies were observed for the HI than for the NH listeners. Only at low click sensation levels, prolonged latencies were obtained...

  14. Low Latency MAC Protocol in Wireless Sensor Networks Using Timing Offset

    Science.gov (United States)

    Choi, Seung Sik

    This paper proposes a low latency MAC protocol that can be used in sensor networks. To extend the lifetime of sensor nodes, the conventional solution is to synchronize active/sleep periods of all sensor nodes. However, due to these synchronized sensor nodes, packets in the intermediate nodes must wait until the next node wakes up before it can forward a packet. This induces a large delay in sensor nodes. To solve this latency problem, a clustered sensor network which uses two types of sensor nodes and layered architecture is considered. Clustered heads in each cluster are synchronized with different timing offsets to reduce the sleep delay. Using this concept, the latency problem can be solved and more efficient power usage can be obtained.

  15. Understanding and Analyzing Latency of Near Real-time Satellite Data

    Science.gov (United States)

    Han, W.; Jochum, M.; Brust, J.

    2016-12-01

    Acquiring and disseminating time-sensitive satellite data in a timely manner is much concerned by researchers and decision makers of weather forecast, severe weather warning, disaster and emergency response, environmental monitoring, and so on. Understanding and analyzing the latency of near real-time satellite data is very useful and helpful to explore the whole data transmission flow, indentify the possible issues, and connect data providers and users better. The STAR (Center for Satellite Applications and Research of NOAA) Central Data Repository (SCDR) is a central repository to acquire, manipulate, and disseminate various types of near real-time satellite datasets to internal and external users. In this system, important timestamps, including observation beginning/end, processing, uploading, downloading, and ingestion, are retrieved and organized in the database, so the time length of each transmission phase can be figured out easily. Open source NoSQL database MongoDB is selected to manage the timestamp information because of features of dynamic schema, aggregation and data processing. A user-friendly user interface is developed to visualize and characterize the latency interactively. Taking the Himawari-8 HSD (Himawari Standard Data) file as an example, the data transmission phases, including creating HSD file from satellite observation, uploading the file to HimawariCloud, updating file link in the webpage, downloading and ingesting the file to SCDR, are worked out from the above mentioned timestamps. The latencies can be observed by time of period, day of week, or hour of day in chart or table format, and the anomaly latencies can be detected and reported through the user interface. Latency analysis provides data providers and users actionable insight on how to improve the data transmission of near real-time satellite data, and enhance its acquisition and management.

  16. Reduction in the latency of action of antidepressants by 17 beta-estradiol in the forced swimming test.

    Science.gov (United States)

    Estrada-Camarena, E; Rivera, N M Vega; Berlanga, C; Fernández-Guasti, A

    2008-12-01

    Antidepressants (ADs) are slow to produce their therapeutic effect. This long latency promotes the development of new strategies to short their onset of action. Previous reports indicated that 17beta-estradiol (E(2)) promotes the antidepressant-like activity of fluoxetine (FLX) and desipramine (DMI) in the forced swimming test (FST). The aim of the present work was to analyze if E(2) reduces the antidepressant-like onset of action of venlafaxine (VLX), FLX, and DMI. Independent groups of ovariectomized female Wistar rats were tested in the FST and in the open field after chronic (1 to 14 days) treatment with VLX (20 mg/kg/day), FLX (1.25 mg/kg/day), or DMI (1.25 mg/kg/day) alone or in combination with a single injection of E(2) (2.5 microg/rat sc, 8 h before FST). VLX, FLX, or DMI by themselves at these doses did not induce changes in the FST at short intervals after their injection (from 1 to 7 days). The addition of E(2) promoted the antidepressant-like effect of VLX and DMI as early as day 1. Such action was also evident after 3, for FLX, and 14 days for both FLX and DMI, but not for VLX. The behavioral actions of these ADs combined with E(2) were not accompanied by increases in general activity in the open-field test. E(2) clearly reduced the latency to the onset of action for these ADs in the FST. These results represent an interesting therapeutic strategy for the treatment of depression in perimenopausal women.

  17. Latency Performance of Encoding with Random Linear Network Coding

    DEFF Research Database (Denmark)

    Nielsen, Lars; Hansen, René Rydhof; Lucani Rötter, Daniel Enrique

    2018-01-01

    the encoding process can be parallelized based on system requirements to reduce data access time within the system. Using a counting argument, we focus on predicting the effect of changes of generation (number of original packets) and symbol size (number of bytes per data packet) configurations on the encoding...... latency on full vector and on-the-fly algorithms. We show that the encoding latency doubles when either the generation size or the symbol size double and confirm this via extensive simulations. Although we show that the theoretical speed gain of on-the-fly over full vector is two, our measurements show...

  18. Multi-User Preemptive Scheduling For Critical Low Latency Communications in 5G Networks

    DEFF Research Database (Denmark)

    Abdul-Mawgood Ali Ali Esswie, Ali; Pedersen, Klaus

    2018-01-01

    5G new radio is envisioned to support three major service classes: enhanced mobile broadband (eMBB), ultrareliable low-latency communications (URLLC), and massive machine type communications. Emerging URLLC services require up to one millisecond of communication latency with 99.999% success...... probability. Though, there is a fundamental trade-off between system spectral efficiency (SE) and achievable latency. This calls for novel scheduling protocols which cross-optimize system performance on user-centric; instead of network-centric basis. In this paper, we develop a joint multi-user preemptive...... scheduling strategy to simultaneously cross-optimize system SE and URLLC latency. At each scheduling opportunity, available URLLC traffic is always given higher priority. When sporadic URLLC traffic appears during a transmission time interval (TTI), proposed scheduler seeks for fitting the URLLC-eMBB traffic...

  19. Ocular herpes simplex virus: how are latency, reactivation, recurrent disease and therapy interrelated?

    Science.gov (United States)

    Al-Dujaili, Lena J; Clerkin, Patrick P; Clement, Christian; McFerrin, Harris E; Bhattacharjee, Partha S; Varnell, Emily D; Kaufman, Herbert E; Hill, James M

    2012-01-01

    Most humans are infected with herpes simplex virus (HSV) type 1 in early childhood and remain latently infected throughout life. While most individuals have mild or no symptoms, some will develop destructive HSV keratitis. Ocular infection with HSV-1 and its associated sequelae account for the majority of corneal blindness in industrialized nations. Neuronal latency in the peripheral ganglia is established when transcription of the viral genome is repressed (silenced) except for the latency-associated transcripts and microRNAs. The functions of latency-associated transcripts have been investigated since 1987. Roles have been suggested relating to reactivation, establishment of latency, neuronal protection, antiapoptosis, apoptosis, virulence and asymptomatic shedding. Here, we review HSV-1 latent infections, reactivation, recurrent disease and antiviral therapies for the ocular HSV diseases. PMID:21861620

  20. Influences for Gender Disparity in Academic Neuroradiology.

    Science.gov (United States)

    Ahmadi, M; Khurshid, K; Sanelli, P C; Jalal, S; Chahal, T; Norbash, A; Nicolaou, S; Castillo, M; Khosa, F

    2018-01-01

    There has been extensive interest in promoting gender equality within radiology, a predominately male field. In this study, our aim was to quantify gender representation in neuroradiology faculty rankings and determine any related factors that may contribute to any such disparity. We evaluated the academic and administrative faculty members of neuroradiology divisions for all on-line listed programs in the US and Canada. After excluding programs that did not fulfill our selection criteria, we generated a short list of 85 US and 8 Canadian programs. We found 465 faculty members who met the inclusion criteria for our study. We used Elsevier's SCOPUS for gathering the data pertaining to the publications, H-index, citations, and tenure of the productivity of each faculty member. Gender disparity was insignificant when analyzing academic ranks. There are more men working in neuroimaging relative to women (χ 2 = 0.46; P = .79). However, gender disparity was highly significant for leadership positions in neuroradiology (χ 2 = 6.76; P = .009). The median H-index was higher among male faculty members (17.5) versus female faculty members (9). Female faculty members have odds of 0.84 compared with male faculty members of having a higher H-index, adjusting for publications, citations, academic ranks, leadership ranks, and interaction between gender and publications and gender and citations (9). Neuroradiology faculty members follow the same male predominance seen in many other specialties of medicine. In this study, issues such as mentoring, role models, opportunities to engage in leadership/research activities, funding opportunities, and mindfulness regarding research productivity are explored. © 2018 by American Journal of Neuroradiology.

  1. Investigation of Koi Herpesvirus Latency in Koi▿

    Science.gov (United States)

    Eide, Kathleen E.; Miller-Morgan, Tim; Heidel, Jerry R.; Kent, Michael L.; Bildfell, Rob J.; LaPatra, Scott; Watson, Gregory; Jin, Ling

    2011-01-01

    Koi herpesvirus (KHV) has recently been classified as a member of the family of Alloherpesviridae within the order of Herpesvirales. One of the unique features of Herpesviridae is latent infection following a primary infection. However, KHV latency has not been recognized. To determine if latency occurs in clinically normal fish from facilities with a history of KHV infection or exposure, the presence of the KHV genome was investigated in healthy koi by PCR and Southern blotting. KHV DNA, but not infectious virus or mRNAs from lytic infection, was detected in white blood cells from investigated koi. Virus shedding was examined via tissue culture and reverse transcription-PCR (RT-PCR) testing of gill mucus and feces from six koi every other day for 1 month. No infectious virus or KHV DNA was detected in fecal secretion or gill swabs, suggesting that neither acute nor persistent infection was present. To determine if KHV latent infections can be reactivated, six koi were subjected to a temperature stress regime. KHV DNA and infectious virus were detected in both gill and fecal swabs by day 8 following temperature stress. KHV DNA was also detectable in brain, spleen, gills, heart, eye, intestine, kidney, liver, and pancreas in euthanized koi 1 month post-temperature stress. Our study suggests that KHV may become latent in leukocytes and other tissues, that it can be reactivated from latency by temperature stress, and that it may be more widespread in the koi population than previously suspected. PMID:21389134

  2. Optimized Interface Diversity for Ultra-Reliable Low Latency Communication (URLLC)

    DEFF Research Database (Denmark)

    Nielsen, Jimmy Jessen; Liu, Rongkuan; Popovski, Petar

    2017-01-01

    An important ingredient of the future 5G systems will be Ultra-Reliable Low-Latency Communication (URLLC). A way to offer URLLC without intervention in the baseband/PHY layer design is to use interface diversity and integrate multiple communication interfaces, each interface based on a different...... technology. Our approach is to use rateless codes to seamlessly distribute coded payload and redundancy data across multiple available communication interfaces. We formulate an optimization problem to find the payload allocation weights that maximize the reliability at specific target latency values...

  3. Disparities in Gynecological Malignancies

    Directory of Open Access Journals (Sweden)

    Sudeshna eChatterjee

    2016-02-01

    Full Text Available Objectives: Health disparities and inequalities in access to care among different socioeconomic, ethnic, and racial groups have been well documented in the U.S. healthcare system. In this review, we aimed to provide an overview of barriers to care contributing to health disparities in gynecological oncology management and to describe site-specific disparities in gynecologic care for endometrial, ovarian, and cervical cancer. Methods: We performed a literature review of peer-reviewed academic and governmental publications focusing on disparities in gynecological care in the United States by searching PubMed and Google Scholar electronic databases. Results: There are multiple important underlying issues that may contribute to the disparities in gynecological oncology management in the United States, namely geographic access and hospital based-discrepancies, research-based discrepancies, influence of socioeconomic and health insurance status, and finally the influence of race and biological factors. Despite the reduction in overall cancer-related deaths since the 1990s, the 5-year survival for Black women is significantly lower than for White women for each gynecologic cancer type and each stage of diagnosis. For ovarian and endometrial cancer, black patients are less likely to receive treatment consistent with evidence-based guidelines and have worse survival outcomes even after accounting for stage and comorbidities. For cervical and endometrial cancer, the mortality rate for black women remains twice that of White women. Conclusions: Health care disparities in the incidence and outcome of gynecologic cancers are complex and involve biologic factors as well as racial, socioeconomic and geographic barriers that influence treatment and survival. These barriers must be addressed to provide optimal care to women in the U.S. with gynecologic cancer.

  4. Trial latencies estimation of event-related potentials in EEG by means of genetic algorithms

    Science.gov (United States)

    Da Pelo, P.; De Tommaso, M.; Monaco, A.; Stramaglia, S.; Bellotti, R.; Tangaro, S.

    2018-04-01

    Objective. Event-related potentials (ERPs) are usually obtained by averaging thus neglecting the trial-to-trial latency variability in cognitive electroencephalography (EEG) responses. As a consequence the shape and the peak amplitude of the averaged ERP are smeared and reduced, respectively, when the single-trial latencies show a relevant variability. To date, the majority of the methodologies for single-trial latencies inference are iterative schemes providing suboptimal solutions, the most commonly used being the Woody’s algorithm. Approach. In this study, a global approach is developed by introducing a fitness function whose global maximum corresponds to the set of latencies which renders the trial signals most aligned as possible. A suitable genetic algorithm has been implemented to solve the optimization problem, characterized by new genetic operators tailored to the present problem. Main results. The results, on simulated trials, showed that the proposed algorithm performs better than Woody’s algorithm in all conditions, at the cost of an increased computational complexity (justified by the improved quality of the solution). Application of the proposed approach on real data trials, resulted in an increased correlation between latencies and reaction times w.r.t. the output from RIDE method. Significance. The above mentioned results on simulated and real data indicate that the proposed method, providing a better estimate of single-trial latencies, will open the way to more accurate study of neural responses as well as to the issue of relating the variability of latencies to the proper cognitive and behavioural correlates.

  5. EOS Data Products Latency and Reprocessing Evaluation

    Science.gov (United States)

    Ramapriyan, H. K.; Wanchoo, L.

    2012-12-01

    NASA's Earth Observing System (EOS) Data and Information System (EOSDIS) program has been processing, archiving, and distributing EOS data since the launch of Terra platform in 1999. The EOSDIS Distributed Active Archive Centers (DAACs) and Science-Investigator-led Processing Systems (SIPSs) are generating over 5000 unique products with a daily average volume of 1.7 Petabytes. Initially EOSDIS had requirements to make process data products within 24 hours of receiving all inputs needed for generating them. Thus, generally, the latency would be slightly over 24 and 48 hours after satellite data acquisition, respectively, for Level 1 and Level 2 products. Due to budgetary constraints these requirements were relaxed, with the requirement being to avoid a growing backlog of unprocessed data. However, the data providers have been generating these products in as timely a manner as possible. The reduction in costs of computing hardware has helped considerably. It is of interest to analyze the actual latencies achieved over the past several years in processing and inserting the data products into the EOSDIS archives for the users to support various scientific studies such as land processes, oceanography, hydrology, atmospheric science, cryospheric science, etc. The instrument science teams have continuously evaluated the data products since the launches of EOS satellites and improved the science algorithms to provide high quality products. Data providers have periodically reprocessed the previously acquired data with these improved algorithms. The reprocessing campaigns run for an extended time period in parallel with forward processing, since all data starting from the beginning of the mission need to be reprocessed. Each reprocessing activity involves more data than the previous reprocessing. The historical record of the reprocessing times would be of interest to future missions, especially those involving large volumes of data and/or computational loads due to

  6. Processing vertical size disparities in distinct depth planes.

    Science.gov (United States)

    Duke, Philip A; Howard, Ian P

    2012-08-17

    A textured surface appears slanted about a vertical axis when the image in one eye is horizontally enlarged relative to the image in the other eye. The surface appears slanted in the opposite direction when the same image is vertically enlarged. Two superimposed textured surfaces with different horizontal size disparities appear as two surfaces that differ in slant. Superimposed textured surfaces with equal and opposite vertical size disparities appear as a single frontal surface. The vertical disparities are averaged. We investigated whether vertical size disparities are averaged across two superimposed textured surfaces in different depth planes or whether they induce distinct slants in the two depth planes. In Experiment 1, two superimposed textured surfaces with different vertical size disparities were presented in two depth planes defined by horizontal disparity. The surfaces induced distinct slants when the horizontal disparity was more than ±5 arcmin. Thus, vertical size disparities are not averaged over surfaces with different horizontal disparities. In Experiment 2 we confirmed that vertical size disparities are processed in surfaces away from the horopter, so the results of Experiment 1 cannot be explained by the processing of vertical size disparities in a fixated surface only. Together, these results show that vertical size disparities are processed separately in distinct depth planes. The results also suggest that vertical size disparities are not used to register slant globally by their effect on the registration of binocular direction of gaze.

  7. Low Latency Audio Video: Potentials for Collaborative Music Making through Distance Learning

    Science.gov (United States)

    Riley, Holly; MacLeod, Rebecca B.; Libera, Matthew

    2016-01-01

    The primary purpose of this study was to examine the potential of LOw LAtency (LOLA), a low latency audio visual technology designed to allow simultaneous music performance, as a distance learning tool for musical styles in which synchronous playing is an integral aspect of the learning process (e.g., jazz, folk styles). The secondary purpose was…

  8. Influence of ageing on carotid baroreflex peak response latency in humans

    DEFF Research Database (Denmark)

    Fisher, J.P.; Kim, A.; Young, C.N.

    2009-01-01

    The stability of a physiological control system, such as the arterial baroreflex, depends critically upon both the magnitude (i.e. gain or sensitivity) and timing (i.e. latency) of the effector response. Although studies have examined resting arterial baroreflex sensitivity in older subjects......, little attention has been given to the influence of ageing on the latency of peak baroreflex responses. First, we compared the temporal pattern of heart rate (HR) and mean arterial blood pressure (BP) responses to selective carotid baroreceptor (CBR) unloading and loading in 14 young (22 +/- 1 years......) and older (61 +/- 1 years) subjects, using 5 s pulses of neck pressure (NP, +35 Torr) and neck suction (NS, -80 Torr). Second, CBR latency was assessed following pharmacological blockade of cardiac parasympathetic nerve activity in eight young subjects, to better understand how known age-related reductions...

  9. The Effect of Consuming Ambon Banana (Musa paradisiaca Var. Sapientum on Sleep Latency of Elderly Hypertension

    Directory of Open Access Journals (Sweden)

    Selvi Ria Ristania

    2017-08-01

    Full Text Available Elderly hypertension often reported that their latency elongated was less compared to healthy elderly. The increase of latency impact on health, it causes susceptibility to illness, stress, confusion, disorientation, mood disorders, less fresh, decrease ability to make decisions. The aim of this research was to explain the effect of consuming Ambon banana on sleep latency of elderly hypertension in Mulyorejo, Surabaya. Time series one group pre-test post test design was used in this research. Affordable population in this research was elderly hypertension in RW 2 and RW 3 Mulyorejo Surabaya. Total sample was 15 respondents and taken by total sampling technique. The independent variable was consuming Ambon banana, and dependent variable was sleep latency of elderly hypertension. Every day the latency and blood pressure on elderly was monitored. Data was collected using questionnaire, and then analyzed using Wilcoxon Signed Rank Test. The result showed that consuming Ambon banana affect sleep latency (p=0.009.

  10. Effect of squatting velocity on hip muscle latency in women with patellofemoral pain syndrome.

    Science.gov (United States)

    Orozco-Chavez, Ignacio; Mendez-Rebolledo, Guillermo

    2018-03-01

    [Purpose] Neuromuscular activity has been evaluated in patellofemoral pain syndrome but movement velocity has not been considered. The aim was to determine differences in onset latency of hip and knee muscles between individuals with and without patellofemoral pain syndrome during a single leg squat, and whether any differences are dependent on movement velocity. [Subjects and Methods] Twenty-four females with patellofemoral pain syndrome and 24 healthy females participated. Onset latency of gluteus maximus, anterior and posterior gluteus medius, rectus femoris, vastus medialis, vastus lateralis and biceps femoris during a single leg squat at high and low velocity were evaluated. [Results] There was an interaction between velocity and diagnosis for posterior gluteus medius. Healthy subjects showed a later posterior gluteus medius onset latency at low velocity than high velocity; and also later than patellofemoral pain syndrome subjects at low velocity and high velocity. [Conclusion] Patellofemoral pain syndrome subjects presented an altered latency of posterior gluteus medius during a single leg squat and did not generate adaptations to velocity variation, while healthy subjects presented an earlier onset latency in response to velocity increase.

  11. Advanced techniques for the analysis of crisis stability, deterrence, and latency

    Energy Technology Data Exchange (ETDEWEB)

    Canavan, G.H.

    1997-12-01

    Studies on crisis stability, deterrence, and latency are presented in chronological order, which also reflects their logical order of development, captures the main features of stability analysis; relates first strike, crisis, and arms control stability as seen from US and Russian perspective; and addresses questions such as whether uncertainty in damage preference or defense deployment can be destabilizing. It illustrates the problems with alternative metrics, latency and reconstitution, and deep unilateral and proportional force reductions.

  12. Low-Latency Embedded Vision Processor (LLEVS)

    Science.gov (United States)

    2016-03-01

    algorithms, low-latency video processing, embedded image processor, wearable electronics, helmet-mounted systems, alternative night / day imaging...external subsystems and data sources with the device. The establishment of data interfaces in terms of data transfer rates, formats and types are...video signals from Near-visible Infrared (NVIR) sensor, Shortwave IR (SWIR) and Longwave IR (LWIR) is the main processing for Night Vision (NI) system

  13. Minority Health and Health Disparities

    Science.gov (United States)

    ... ik People" People Awakening Resilience Project (PARP), Cuqyun "Measuring" Treatment and Health Services Research Alcohol Treatment and ... addressing Health Disparities . 1 2009-2013 Health Disparities Strategic Plan, p.4 2 Ibid, p.4 3 ...

  14. Gum chewing improves swallow frequency and latency in Parkinson patients: a preliminary study.

    Science.gov (United States)

    South, Angela R; Somers, Stephanie M; Jog, Mandar S

    2010-04-13

    Reduced swallowing frequency affects secretion management in Parkinson disease (PD). Gum chewing increases saliva flow and swallow frequency. This study uses chewing gum to modify swallow frequency and latency between swallows in patients with PD. 1) Assess the frequency and latency of swallow at baseline (BL), during gum chewing (GC), and post gum chewing (PGC) for participants with PD (stage 2-4) nonsymptomatic for prandial dysphagia; and 2) assess carryover after gum is expectorated. Twenty participants were studied across 3 tasks, each of 5 minutes in duration: BL, GC, and PGC. Respiratory and laryngeal signals were continuously recorded using PowerLab (version 5.5.5; ADI Instruments, Castle Hill, Australia). Frequency and latency of swallow events were calculated. Differences (analysis of variance) are reported for frequency (p Parkinson disease. This study provides Class III evidence that chewing gum increases swallow frequency and decreases latency of swallowing in an experiment in patients with stage 2 to 4 Parkinson disease who are nonsymptomatic for significant prandial dysphagia.

  15. Latency-Based and Psychophysiological Measures of Sexual Interest Show Convergent and Concurrent Validity.

    Science.gov (United States)

    Ó Ciardha, Caoilte; Attard-Johnson, Janice; Bindemann, Markus

    2018-04-01

    Latency-based measures of sexual interest require additional evidence of validity, as do newer pupil dilation approaches. A total of 102 community men completed six latency-based measures of sexual interest. Pupillary responses were recorded during three of these tasks and in an additional task where no participant response was required. For adult stimuli, there was a high degree of intercorrelation between measures, suggesting that tasks may be measuring the same underlying construct (convergent validity). In addition to being correlated with one another, measures also predicted participants' self-reported sexual interest, demonstrating concurrent validity (i.e., the ability of a task to predict a more validated, simultaneously recorded, measure). Latency-based and pupillometric approaches also showed preliminary evidence of concurrent validity in predicting both self-reported interest in child molestation and viewing pornographic material containing children. Taken together, the study findings build on the evidence base for the validity of latency-based and pupillometric measures of sexual interest.

  16. Trade-off between synergy and efficacy in combinations of HIV-1 latency-reversing agents.

    Science.gov (United States)

    Gupta, Vipul; Dixit, Narendra M

    2018-02-01

    Eradicating HIV-1 infection is difficult because of the reservoir of latently infected cells that gets established soon after infection, remains hidden from antiretroviral drugs and host immune responses, and retains the capacity to reignite infection following the cessation of treatment. Drugs called latency-reversing agents (LRAs) are being developed to reactivate latently infected cells and render them susceptible to viral cytopathicity or immune killing. Whereas individual LRAs have failed to induce adequate reactivation, pairs of LRAs have been identified recently that act synergistically and hugely increase reactivation levels compared to individual LRAs. The maximum synergy achievable with LRA pairs is of clinical importance, as it would allow latency-reversal with minimal drug exposure. Here, we employed stochastic simulations of HIV-1 transcription and translation in latently infected cells to estimate this maximum synergy. We incorporated the predominant mechanisms of action of the two most promising classes of LRAs, namely, protein kinase C agonists and histone deacetylase inhibitors, and quantified the activity of individual LRAs in the two classes by mapping our simulations to corresponding in vitro experiments. Without any adjustable parameters, our simulations then quantitatively captured experimental observations of latency-reversal when the LRAs were used in pairs. Performing simulations representing a wide range of drug concentrations, we estimated the maximum synergy achievable with these LRA pairs. Importantly, we found with all the LRA pairs we considered that concentrations yielding the maximum synergy did not yield the maximum latency-reversal. Increasing concentrations to increase latency-reversal compromised synergy, unravelling a trade-off between synergy and efficacy in LRA combinations. The maximum synergy realizable with LRA pairs would thus be restricted by the desired level of latency-reversal, a constrained optimum we elucidated with

  17. Counties eliminating racial disparities in colorectal cancer mortality.

    Science.gov (United States)

    Rust, George; Zhang, Shun; Yu, Zhongyuan; Caplan, Lee; Jain, Sanjay; Ayer, Turgay; McRoy, Luceta; Levine, Robert S

    2016-06-01

    Although colorectal cancer (CRC) mortality rates are declining, racial-ethnic disparities in CRC mortality nationally are widening. Herein, the authors attempted to identify county-level variations in this pattern, and to characterize counties with improving disparity trends. The authors examined 20-year trends in US county-level black-white disparities in CRC age-adjusted mortality rates during the study period between 1989 and 2010. Using a mixed linear model, counties were grouped into mutually exclusive patterns of black-white racial disparity trends in age-adjusted CRC mortality across 20 three-year rolling average data points. County-level characteristics from census data and from the Area Health Resources File were normalized and entered into a principal component analysis. Multinomial logistic regression models were used to test the relation between these factors (clusters of related contextual variables) and the disparity trend pattern group for each county. Counties were grouped into 4 disparity trend pattern groups: 1) persistent disparity (parallel black and white trend lines); 2) diverging (widening disparity); 3) sustained equality; and 4) converging (moving from disparate outcomes toward equality). The initial principal component analysis clustered the 82 independent variables into a smaller number of components, 6 of which explained 47% of the county-level variation in disparity trend patterns. County-level variation in social determinants, health care workforce, and health systems all were found to contribute to variations in cancer mortality disparity trend patterns from 1990 through 2010. Counties sustaining equality over time or moving from disparities to equality in cancer mortality suggest that disparities are not inevitable, and provide hope that more communities can achieve optimal and equitable cancer outcomes for all. Cancer 2016;122:1735-48. © 2016 American Cancer Society. © 2016 American Cancer Society.

  18. Epigenetic regulation of HIV-1 latency: focus on polycomb group (PcG) proteins.

    Science.gov (United States)

    Khan, Sheraz; Iqbal, Mazhar; Tariq, Muhammad; Baig, Shahid M; Abbas, Wasim

    2018-01-01

    HIV-1 latency allows the virus to persist until reactivation, in a transcriptionally silent form in its cellular reservoirs despite the presence of effective cART. Such viral persistence represents a major barrier to HIV eradication since treatment interruption leads to rebound plasma viremia. Polycomb group (PcG) proteins have recently got a considerable attention in regulating HIV-1 post-integration latency as they are involved in the repression of proviral gene expression through the methylation of histones. This epigenetic regulation plays an important role in the establishment and maintenance of HIV-1 latency. In fact, PcG proteins act in complexes and modulate the epigenetic signatures of integrated HIV-1 promoter. Key role played by PcG proteins in the molecular control of HIV-1 latency has led to hypothesize that PcG proteins may represent a valuable target for future HIV-1 therapy in purging HIV-1 reservoirs. In this regard, various small molecules have been synthesized or explored to specifically block the epigenetic activity of PcG. In this review, we will highlight the possible therapeutic approaches to achieve either a functional or sterilizing cure of HIV-1 infection with special focus on histone methylation by PcG proteins together with current and novel pharmacological approaches to reactivate HIV-1 from latency that could ultimately lead towards a better clearance of viral latent reservoirs.

  19. Measuring the Latency of an Augmented Reality System for Robot-Assisted Minimally Invasive Surgery

    DEFF Research Database (Denmark)

    Jørgensen, Martin Kibsgaard; Kraus, Martin

    2017-01-01

    visual communication in training for robot-assisted minimally invasive surgery with da Vinci surgical systems. To make sure that our augmented reality system provides the best possible user experience, we investigated the video latency of the da Vinci surgical system and how the components of our system...... affect the overall latency. To measure the photon-to-photon latency, we used a microcontroller to determine the time between the activation of a lightemitting diode in front of the endoscopic camera and the corresponding increase in intensity of the surgeon's display as measured by a phototransistor...

  20. Latency of Epstein-Barr virus is stabilized by antisense-mediated control of the viral immediate-early gene BZLF-1.

    Science.gov (United States)

    Prang, N; Wolf, H; Schwarzmann, F

    1999-12-01

    The ability of the Epstein-Barr virus (EBV) to avoid lytic replication and to establish a latent infection in B-lymphocytes is fundamental for its lifelong persistence and the pathogenesis of various EBV-associated diseases. The viral immediate-early gene BZLF-1 plays a key role for the induction of lytic replication and its activity is strictly regulated on different levels of gene expression. Recently, it was demonstrated that BZLF-1 is also controlled by a posttranscriptional mechanism. Transient synthesis of a mutated competitor RNA saturated this mechanism and caused both expression of the BZLF-1 protein and the induction of lytic viral replication. Using short overlapping fragments of the competitor, it is shown that this control acts on the unspliced primary transcript. RT-PCR demonstrated unspliced BZLF-1 RNA in latently infected B-lymphocytes in the absence of BZLF-1 protein. Due to the complementarity of the gene BZLF-1 and the latency-associated gene EBNA-1 on the opposite strand of the genome, we propose an antisense-mediated mechanism. RNase protection assays demonstrated transcripts in antisense orientation to the BZLF-1 transcript during latency, which comprise a comparable constellation to other herpesviruses. A combined RNAse protection/RT-PCR assay detected the double-stranded hybrid RNA, consisting of the unspliced BZLF-1 transcript and a noncoding intron of the EBNA-1 gene. Binding of BZLF-1 transcripts is suggested to be an important backup control mechanism in addition to transcriptional regulation, stabilizing latency and preventing inappropriate lytic viral replication in vivo. Copyright 1999 Wiley-Liss, Inc.

  1. The effects of pay for performance on disparities in stroke, hypertension, and coronary heart disease management: interrupted time series study.

    Science.gov (United States)

    Lee, John Tayu; Netuveli, Gopalakrishnan; Majeed, Azeem; Millett, Christopher

    2011-01-01

    The Quality and Outcomes Framework (QOF), a major pay-for-performance programme, was introduced into United Kingdom primary care in April 2004. The impact of this programme on disparities in health care remains unclear. This study examines the following questions: has this pay for performance programme improved the quality of care for coronary heart disease, stroke and hypertension in white, black and south Asian patients? Has this programme reduced disparities in the quality of care between these ethnic groups? Did general practices with different baseline performance respond differently to this programme? Retrospective cohort study of patients registered with family practices in Wandsworth, London during 2007. Segmented regression analysis of interrupted time series was used to take into account the previous time trend. Primary outcome measures were mean systolic and diastolic blood pressure, and cholesterol levels. Our findings suggest that the implementation of QOF resulted in significant short term improvements in blood pressure control. The magnitude of benefit varied between ethnic groups with a statistically significant short term reduction in systolic BP in white and black but not in south Asian patients with hypertension. Disparities in risk factor control were attenuated only on few measures and largely remained intact at the end of the study period. Pay for performance programmes such as the QOF in the UK should set challenging but achievable targets. Specific targets aimed at reducing ethnic disparities in health care may also be needed.

  2. The disparity mutagenesis model predicts rescue of living things from catastrophic errors

    Directory of Open Access Journals (Sweden)

    Mitsuru eFurusawa

    2014-12-01

    Full Text Available In animals including humans, mutation rates per generation will exceed a perceived threshold, which should result in an excessive genetic load. Despite this, they have survived without extinction. This is a perplexing problem for human genetics, arising at the end of the last century, and to date still does not have a fully satisfactory explanation. Shortly after we proposed the disparity theory of evolution in 1992, the disparity mutagenesis model was proposed, which forms the basis for an explanation for an acceleration of evolution and species survival. This model predicts a significant increase of the mutation threshold values if there is a high enough fidelity difference in replication between the lagging and leading strands. When applied to biological evolution, the model predicts that living things, including humans, might overcome the lethal effect of accumulated deleterious mutations and be able to survive. Artificially-prepared mutator strains of microorganisms, in which an enhanced lagging-strand-biased mutagenesis was introduced, showed unexpectedly high adaptability to severe environments. The implications of the striking behaviors shown by these disparity mutators will be discussed in relation to how living things with high mutation rates can avoid the self-defeating risk of excess mutations.

  3. Maternal sensitivity and latency to positive emotion following challenge: pathways through effortful control.

    Science.gov (United States)

    Conway, Anne; McDonough, Susan C; Mackenzie, Michael; Miller, Alison; Dayton, Carolyn; Rosenblum, Katherine; Muzik, Maria; Sameroff, Arnold

    2014-01-01

    The ability to self-generate positive emotions is an important component of emotion regulation. In this study, we focus on children's latency to express positive emotions following challenging situations and assess whether this ability operates through early maternal sensitivity and children's effortful control. Longitudinal relations between maternal sensitivity, infant negative affect, effortful control, and latency to positive emotion following challenge were examined in 156 children who were 33 months of age. Structural equation models supported the hypothesis that maternal sensitivity during infancy predicted better effortful control and, in turn, shorter latencies to positive emotions following challenge at 33 months. Directions for future research are discussed. © 2014 Michigan Association for Infant Mental Health.

  4. Measurement-based analysis of error latency. [in computer operating system

    Science.gov (United States)

    Chillarege, Ram; Iyer, Ravishankar K.

    1987-01-01

    This paper demonstrates a practical methodology for the study of error latency under a real workload. The method is illustrated with sampled data on the physical memory activity, gathered by hardware instrumentation on a VAX 11/780 during the normal workload cycle of the installation. These data are used to simulate fault occurrence and to reconstruct the error discovery process in the system. The technique provides a means to study the system under different workloads and for multiple days. An approach to determine the percentage of undiscovered errors is also developed and a verification of the entire methodology is performed. This study finds that the mean error latency, in the memory containing the operating system, varies by a factor of 10 to 1 (in hours) between the low and high workloads. It is found that of all errors occurring within a day, 70 percent are detected in the same day, 82 percent within the following day, and 91 percent within the third day. The increase in failure rate due to latency is not so much a function of remaining errors but is dependent on whether or not there is a latent error.

  5. Latency Analysis of Systems with Multiple Interfaces for Ultra-Reliable M2M Communication

    DEFF Research Database (Denmark)

    Nielsen, Jimmy Jessen; Popovski, Petar

    2016-01-01

    One of the ways to satisfy the requirements of ultra-reliable low latency communication for mission critical Machine-type Communications (MTC) applications is to integrate multiple communication interfaces. In order to estimate the performance in terms of latency and reliability of such an integr...

  6. Nocturnal rapid eye movement sleep latency for identifying patients with narcolepsy/hypocretin deficiency.

    Science.gov (United States)

    Andlauer, Olivier; Moore, Hyatt; Jouhier, Laura; Drake, Christopher; Peppard, Paul E; Han, Fang; Hong, Seung-Chul; Poli, Francesca; Plazzi, Giuseppe; O'Hara, Ruth; Haffen, Emmanuel; Roth, Thomas; Young, Terry; Mignot, Emmanuel

    2013-07-01

    Narcolepsy, a disorder associated with HLA-DQB1*06:02 and caused by hypocretin (orexin) deficiency, is diagnosed using the Multiple Sleep Latency Test (MSLT) following nocturnal polysomnography (NPSG). In many patients, a short rapid eye movement sleep latency (REML) during the NPSG is also observed but not used diagnostically. To determine diagnostic accuracy and clinical utility of nocturnal REML measures in narcolepsy/hypocretin deficiency. Observational study using receiver operating characteristic curves for NPSG REML and MSLT findings (sleep studies performed between May 1976 and September 2011 at university medical centers in the United States, China, Korea, and Europe) to determine optimal diagnostic cutoffs for narcolepsy/hypocretin deficiency compared with different samples: controls, patients with other sleep disorders, patients with other hypersomnias, and patients with narcolepsy with normal hypocretin levels. Increasingly stringent comparisons were made. In a first comparison, 516 age- and sex-matched patients with narcolepsy/hypocretin deficiency were selected from 1749 patients and compared with 516 controls. In a second comparison, 749 successive patients undergoing sleep evaluation for any sleep disorders (low pretest probability for narcolepsy) were compared within groups by final diagnosis of narcolepsy/hypocretin deficiency. In the third comparison, 254 patients with a high pretest probability of having narcolepsy were compared within group by their final diagnosis. Finally, 118 patients with narcolepsy/hypocretin deficiency were compared with 118 age- and sex-matched patients with a diagnosis of narcolepsy but with normal hypocretin levels. Sensitivity and specificity of NPSG REML and MSLT as diagnostic tests for narcolepsy/hypocretin deficiency. This diagnosis was defined as narcolepsy associated with cataplexy plus HLA-DQB1*06:02 positivity (no cerebrospinal fluid hypocretin-1 results available) or narcolepsy with documented low (≤ 110 pg

  7. Duration of symptomatology and median segmental sensory latency in 993 carpal tunnel syndrome hands (668 cases

    Directory of Open Access Journals (Sweden)

    KOUYOUMDJIAN JOAO ARIS

    1999-01-01

    Full Text Available According to median sensory nerve action potential onset-latency to index finger in a 140 mm fixed distance, 993 carpal tunnel syndrome (CTS hands from 668 patients were grouped into MIld (3.0 to 3.5 ms, 384 hands, MOderate (3.6 to 4.4 ms, 332 hands, SEvere (> 4.4 ms, 135 hands and UNrecordable (142 hands and correlated with CTS symptomatology duration. All patients have sensory antidromic median-radial latency difference (MRD e > or = 1.0 ms without any doubt about CTS diagnosis. Patients with systemic disease, trauma or previous surgery were excluded. There is a remarkable cumulative percentage increase from 1 to 12 months in group UN (3.5% to 38.7%, 11 folds, much less than the group MI (13.8% to 54.6%, 3.9 folds. There is also a remarkable non-cumulative percentage increase in group UN, from 1 to 4-12 months; the group MI had a relatively uniform distribution in all symptomatic duration groups from 1 to > 60 months. The conclusion is that median nerve compression at carpal tunnel can lead to unrecordable potentials in a relatively short period from 1 to 12 months of evolution, suggesting acute/subacute deterioration. Electrophysiological evaluation must be done periodically in patients that underwent clinical treatment, since cumulative 38.7% of group UN was found in 12 months period.

  8. Global EOS: exploring the 300-ms-latency region

    Science.gov (United States)

    Mascetti, L.; Jericho, D.; Hsu, C.-Y.

    2017-10-01

    EOS, the CERN open-source distributed disk storage system, provides the highperformance storage solution for HEP analysis and the back-end for various work-flows. Recently EOS became the back-end of CERNBox, the cloud synchronisation service for CERN users. EOS can be used to take advantage of wide-area distributed installations: for the last few years CERN EOS uses a common deployment across two computer centres (Geneva-Meyrin and Budapest-Wigner) about 1,000 km apart (∼20-ms latency) with about 200 PB of disk (JBOD). In late 2015, the CERN-IT Storage group and AARNET (Australia) set-up a challenging R&D project: a single EOS instance between CERN and AARNET with more than 300ms latency (16,500 km apart). This paper will report about the success in deploy and run a distributed storage system between Europe (Geneva, Budapest), Australia (Melbourne) and later in Asia (ASGC Taipei), allowing different type of data placement and data access across these four sites.

  9. Latency in vitro using irradiated Herpes simplex virus

    International Nuclear Information System (INIS)

    Nishiyama, Y.; Rapp, F.

    1981-01-01

    Human embryonic fibroblasts infected with u.v.-irradiated herpes simplex virus type 2 (HSV-2, strain 186) and maintained at 40.5 0 C did not yield detectable virus. Virus synthesis was induced by temperature shift-down to 36.5 0 C. The induced virus grew very poorly and was inactivated very rapidly at 40.5 0 C. Non-irradiated virus failed to establish latency at 40.5 0 C in infected cells. Enhanced reactivation of HSV-2 was observed when latently infected cultures were superinfected with human cytomegalovirus (HCMV) or irradiated with a small dose of u.v. light at the time of temperature shift-down. HCMV did not enhance synthesis of HSV-2 during a normal growth cycle but did enhance synthesis of u.v.-irradiated HSV-2. These observations suggest that in this in vitro latency system, some HSV genomes damaged by u.v. irradiation were maintained in a non-replicating state without being destroyed or significantly repaired. (author)

  10. Measurement and analysis of workload effects on fault latency in real-time systems

    Science.gov (United States)

    Woodbury, Michael H.; Shin, Kang G.

    1990-01-01

    The authors demonstrate the need to address fault latency in highly reliable real-time control computer systems. It is noted that the effectiveness of all known recovery mechanisms is greatly reduced in the presence of multiple latent faults. The presence of multiple latent faults increases the possibility of multiple errors, which could result in coverage failure. The authors present experimental evidence indicating that the duration of fault latency is dependent on workload. A synthetic workload generator is used to vary the workload, and a hardware fault injector is applied to inject transient faults of varying durations. This method makes it possible to derive the distribution of fault latency duration. Experimental results obtained from the fault-tolerant multiprocessor at the NASA Airlab are presented and discussed.

  11. Nimodipine-induced hypotension but not nitroglycerin-induced hypotension preserves long- and short-term memory in adult mice.

    Science.gov (United States)

    Haile, Michael; Galoyan, Samuel; Li, Yong-Sheng; Cohen, Barry H; Quartermain, David; Blanck, Thomas; Bekker, Alex

    2012-05-01

    Acute hypotension may be implicated in cognitive dysfunction. L-type calcium channel blockers in the setting of hypoxia are protective of learning and memory. We tested the hypothesis that hypotension induced by nimodipine (NIMO) and nicardipine (NICA) would be protective of long- and short-term memory compared to hypotension induced by nitroglycerin (NTG). Forty Swiss-Webster mice (30 to 35 g, 6 to 8 weeks) were randomized into 4 groups for i.p. injection immediately after passive avoidance (PA) learning on day 0: (1) NTG (30 mg/kg); (2) NICA (40 mg/kg); (3) NIMO (40 mg/kg); and (4) saline. PA training latencies (seconds) were recorded for entry from a suspended platform into a Plexiglas tube where a shock (0.3 mA; 2-second duration) was automatically delivered. On day 2 latencies were recorded during a testing trial during which no shock was delivered. Latencies >900 seconds were assigned this value. Lower testing latency is indicative of an impairment of long-term associative memory. Forty-nine additional mice were randomized into similar groups for object recognition testing (ORT) and given i.p. injections on day 0. ORT measures short-term memory by exploiting the tendency of mice to prefer novel objects where a familiar object is present. On day 5 during training, 2 identical objects were placed in a circular arena and mice explored both for 15 minutes. A testing trial was conducted 1 hour later for 3 minutes after a novel object replaced a familiar one. Mice with intact memory spend about 65% of the time exploring the novel object. Mice with impaired memory devote equal time to each object. Recognition index (RI) is defined as the ratio of time spent exploring the novel object to time spent exploring both objects was the measure of memory. Mean arterial blood pressure (MAP), cerebral bloodflow, and body and brain oxygenation (PO(2)) studies were done in separate groups of mice to determine the dosages for matched degrees of hypotension and the physiological

  12. Epstein-Barr virus growth/latency III program alters cellular microRNA expression

    International Nuclear Information System (INIS)

    Cameron, Jennifer E.; Fewell, Claire; Yin, Qinyan; McBride, Jane; Wang Xia; Lin Zhen

    2008-01-01

    The Epstein-Barr virus (EBV) is associated with lymphoid and epithelial cancers. Initial EBV infection alters lymphocyte gene expression, inducing cellular proliferation and differentiation as the virus transitions through consecutive latency transcription programs. Cellular microRNAs (miRNAs) are important regulators of signaling pathways and are implicated in carcinogenesis. The extent to which EBV exploits cellular miRNAs is unknown. Using micro-array analysis and quantitative PCR, we demonstrate differential expression of cellular miRNAs in type III versus type I EBV latency including elevated expression of miR-21, miR-23a, miR-24, miR-27a, miR-34a, miR-146a and b, and miR-155. In contrast, miR-28 expression was found to be lower in type III latency. The EBV-mediated regulation of cellular miRNAs may contribute to EBV signaling and associated cancers

  13. LATENCY DETERMINATION AND COMPENSATION IN REAL-TIME GNSS/INS INTEGRATED NAVIGATION SYSTEMS

    Directory of Open Access Journals (Sweden)

    P. D. Solomon

    2012-09-01

    Full Text Available Unmanned Aerial Vehicle (UAV technology is now commonplace in many defence and civilian environments. However, the high cost of owning and operating a sophisticated UAV has slowed their adoption in many commercial markets. Universities and research groups are actively experimenting with UAVs to further develop the technology, particularly for automated flying operations. The two main UAV platforms used are fixed-wing and helicopter. Helicopter-based UAVs offer many attractive features over fixed-wing UAVs, including vertical take-off, the ability to loiter, and highly dynamic flight. However the control and navigation of helicopters are significantly more demanding than those of fixed-wing UAVs and as such require a high bandwidth real-time Position, Velocity, Attitude (PVA navigation system. In practical Real-Time Navigation Systems (RTNS there are delays in the processing of the GNSS data prior to the fusion of the GNSS data with the INS measurements. This latency must be compensated for otherwise it degrades the solution of the navigation filter. This paper investigates the effect of latency in the arrival time of the GNSS data in a RTNS. Several test drives and flights were conducted with a low-cost RTNS, and compared with a high quality GNSS/INS solution. A technique for the real-time, automated and accurate estimation of the GNSS latency in low-cost systems was developed and tested. The latency estimates were then verified through cross-correlation with the time-stamped measurements from the reference system. A delayed measurement Extended Kalman Filter was then used to allow for the real-time fusing of the delayed measurements, and then a final system developed for on-the-fly measurement and compensation of GNSS latency in a RTNS.

  14. Latency Determination and Compensation in Real-Time Gnss/ins Integrated Navigation Systems

    Science.gov (United States)

    Solomon, P. D.; Wang, J.; Rizos, C.

    2011-09-01

    Unmanned Aerial Vehicle (UAV) technology is now commonplace in many defence and civilian environments. However, the high cost of owning and operating a sophisticated UAV has slowed their adoption in many commercial markets. Universities and research groups are actively experimenting with UAVs to further develop the technology, particularly for automated flying operations. The two main UAV platforms used are fixed-wing and helicopter. Helicopter-based UAVs offer many attractive features over fixed-wing UAVs, including vertical take-off, the ability to loiter, and highly dynamic flight. However the control and navigation of helicopters are significantly more demanding than those of fixed-wing UAVs and as such require a high bandwidth real-time Position, Velocity, Attitude (PVA) navigation system. In practical Real-Time Navigation Systems (RTNS) there are delays in the processing of the GNSS data prior to the fusion of the GNSS data with the INS measurements. This latency must be compensated for otherwise it degrades the solution of the navigation filter. This paper investigates the effect of latency in the arrival time of the GNSS data in a RTNS. Several test drives and flights were conducted with a low-cost RTNS, and compared with a high quality GNSS/INS solution. A technique for the real-time, automated and accurate estimation of the GNSS latency in low-cost systems was developed and tested. The latency estimates were then verified through cross-correlation with the time-stamped measurements from the reference system. A delayed measurement Extended Kalman Filter was then used to allow for the real-time fusing of the delayed measurements, and then a final system developed for on-the-fly measurement and compensation of GNSS latency in a RTNS.

  15. Disseminating Health Disparities Education Through Tele-Learning

    Directory of Open Access Journals (Sweden)

    LaSonya Knowles

    2008-08-01

    Full Text Available Twenty years of research demonstrate that there are wide disparities in health throughout America. Health disparities are differences in the incidence, prevalence, mortality, and burden of diseases and other adverse health conditions that exist when specific population subgroups are compared. Health Disparities in America: Working Toward Social Justice is a course instructed every fall by Dr. Lovell Jones, director of The Center for Research on Minority Health (CRMH at UT M.D. Anderson Cancer Center. The CRMH has created a course that examines the social and societal factors that are fundamental in creating disparities in health. Students from 10 different academic programs and institutions participate in this course. The course is unique in the aspect that various, diverse speakers whom are experts in their field of study instruct each class. This health disparities course is conducted at one of three different academic institutions in the Houston area and broadcast via satellite to various academic institutions by means of teleeducation. Tele-education is defined as a mode of instruction utilizing different forms of media such as video, audio technology tools and computers. Video and audio technologies involve the transmission of interface between learners and instructors, either interactive or non-interactive. Tele-education technologies have an important role to play in addressing the dissemination of health disparities education. The purpose of this program is to determine the feasibility of tele-education as a mode of instruction to introduce the multi-disciplinary components of health disparities. Our findings suggest that tele-education is a useful tool in imparting health disparities education.

  16. A long baseline global stereo matching based upon short baseline estimation

    Science.gov (United States)

    Li, Jing; Zhao, Hong; Li, Zigang; Gu, Feifei; Zhao, Zixin; Ma, Yueyang; Fang, Meiqi

    2018-05-01

    In global stereo vision, balancing the matching efficiency and computing accuracy seems to be impossible because they contradict each other. In the case of a long baseline, this contradiction becomes more prominent. In order to solve this difficult problem, this paper proposes a novel idea to improve both the efficiency and accuracy in global stereo matching for a long baseline. In this way, the reference images located between the long baseline image pairs are firstly chosen to form the new image pairs with short baselines. The relationship between the disparities of pixels in the image pairs with different baselines is revealed by considering the quantized error so that the disparity search range under the long baseline can be reduced by guidance of the short baseline to gain matching efficiency. Then, the novel idea is integrated into the graph cuts (GCs) to form a multi-step GC algorithm based on the short baseline estimation, by which the disparity map under the long baseline can be calculated iteratively on the basis of the previous matching. Furthermore, the image information from the pixels that are non-occluded under the short baseline but are occluded for the long baseline can be employed to improve the matching accuracy. Although the time complexity of the proposed method depends on the locations of the chosen reference images, it is usually much lower for a long baseline stereo matching than when using the traditional GC algorithm. Finally, the validity of the proposed method is examined by experiments based on benchmark datasets. The results show that the proposed method is superior to the traditional GC method in terms of efficiency and accuracy, and thus it is suitable for long baseline stereo matching.

  17. HyspIRI Low Latency Concept and Benchmarks

    Science.gov (United States)

    Mandl, Dan

    2010-01-01

    Topics include HyspIRI low latency data ops concept, HyspIRI data flow, ongoing efforts, experiment with Web Coverage Processing Service (WCPS) approach to injecting new algorithms into SensorWeb, low fidelity HyspIRI IPM testbed, compute cloud testbed, open cloud testbed environment, Global Lambda Integrated Facility (GLIF) and OCC collaboration with Starlight, delay tolerant network (DTN) protocol benchmarking, and EO-1 configuration for preliminary DTN prototype.

  18. Low-latency data analysis for the spherical detector Mario Schenberg

    International Nuclear Information System (INIS)

    Costa, Carlos Filipe Da Silva; Costa, César Augusto; Aguiar, Odylio Denys

    2014-01-01

    The confrontation of gravitational waves (GWs) with their electromagnetic (EM) counterparts will be rich with information about astrophysical events. Initially, this confrontation will corroborate GW detections; afterwards, when GW detections become more recurrent, it will allow astrophysics to combine information from different channels (GW, EM and also neutrinos). A low-latency data analysis which provides the direction of an incoming GW candidate is required to confront it with fast follow-up EM observations. Until now, no low-latency data analysis has been developed for spherical detectors. One spherical detector alone is capable of determining both the GW direction and polarization. By using this capability, we have developed a low-latency data analysis pipeline for the Mario Schenberg detector. This pipeline is able to retrieve the direction of GW triggers with an average angular resolution from δs ∼ 8° at SNR ∼ 12 to δs ∼ 1° at SNR ∼ 80, in a timespan of a 4 s for 32 s of data being analyzed. We apply a veto which reduces fake events up to 90% when maintaining the GW efficiency above 90% for high SNRs. We provide here a description of the method and its efficiency: resolution on the direction, false alarm rate and computational time. (paper)

  19. Health disparities through a psychological lens.

    Science.gov (United States)

    Adler, Nancy E

    2009-11-01

    There is growing concern in the United States about avoidable, unjust differences in health associated with sociodemographic characteristics, such as socioeconomic status and race/ethnicity. This concern has sparked research to identify how disparities develop and how they can be reduced. Studies showing that disparities occur at all levels of socioeconomic status, not simply at the very bottom, suggest that psychosocial factors play an important role. The author discusses both content and process issues in psychological research on disparities. Copyright 2009 by the American Psychological Association

  20. Advanced techniques for the analysis of crisis stability, deterrence, and latency

    Energy Technology Data Exchange (ETDEWEB)

    Canavan, G.H.

    1998-12-31

    This is the final report of a one-year, Laboratory Directed Research and Development (LDRD) project at Los Alamos National Laboratory (LANL). The principal results of studies on crisis stability, deterrence, and latency are presented in their order of development. They capture the main features of stability analysis; relate first strike, crisis, and arms control stability as seen from US and Russian perspective; and address whether different metrics, uncertain damage preferences, or the deployment of defenses can be destabilizing. The report explores differences between unilateral and proportional force reductions in the region of deep reductions where concern shifts from stability to latency.

  1. Do wealth disparities contribute to health disparities within racial/ethnic groups?

    Science.gov (United States)

    Pollack, Craig Evan; Cubbin, Catherine; Sania, Ayesha; Hayward, Mark; Vallone, Donna; Flaherty, Brian; Braveman, Paula A

    2013-05-01

    Though wide disparities in wealth have been documented across racial/ethnic groups, it is largely unknown whether differences in wealth are associated with health disparities within racial/ethnic groups. Data from the Survey of Consumer Finances (2004, ages 25-64) and the Health and Retirement Survey (2004, ages 50+), containing a wide range of assets and debts variables, were used to calculate net worth (a standard measure of wealth). Among non-Hispanic black, Hispanic and non-Hispanic white populations, we tested whether wealth was associated with self-reported poor/fair health status after accounting for income and education. Except among the younger Hispanic population, net worth was significantly associated with poor/fair health status within each racial/ethnic group in both data sets. Adding net worth attenuated the association between education and poor/fair health (in all racial/ethnic groups) and between income and poor/fair health (except among older Hispanics). The results add to the literature indicating the importance of including measures of wealth in health research for what they may reveal about disparities not only between but also within different racial/ethnic groups.

  2. Fine mapping of the latency-related gene of herpes simplex virus type 1: alternative splicing produces distinct latency-related RNAs containing open reading frames

    International Nuclear Information System (INIS)

    Wechsler, S.L.; Nesburn, A.B.; Watson, R.; Slanina, S.M.; Ghiasi, H.

    1988-01-01

    The latency-related (LR) gene of herpes simplex virus type 1 (HSV-1) is transcriptionally active during HSV-1 latency, producing at least two LR-RNAs. The LR gene partially overlaps the immediate-early gene ICP0 and is transcribed in the opposite direction from ICP0, producing LR-RNAs that are complementary (antisense) to ICP0 mRNA. The LR gene is thought to be involved in HSV-1 latency. The authors report here the time mapping and partial sequence analysis of this HSV-1 LR gene. 32 P-labeled genomic DNA restriction fragments and synthetic oligonucleotides were used as probes for in situ hybridizations and Northern (RNA) blot hybridizations of RNA from trigeminal ganglia of rabbits latently infected with HSV-1. The two most abundant LR-RNAs appeared to share their 5' and 3' ends and to be produced by alternative splicing. These LR-RNAs were approximately 2 and 1.3 to 1.5 kilobases in length and were designated LR-RNA 1 and LF-RNA 2, respectively. LR-RNA 1 appeared to have at least one intron removed, while LR-RNA 2 appeared to have at least two introns removed. The LR-RNAs contained two potential long open reading frames, suggesting the possibility that one or more of the LR-RNAs may be a functional mRNA

  3. Serotonin transporter promoter region (5-HTTLPR) polymorphism is associated with the intravaginal ejaculation latency time in Dutch men with lifelong premature ejaculation.

    Science.gov (United States)

    Janssen, Paddy K C; Bakker, Steven C; Réthelyi, Janos; Zwinderman, Aeilko H; Touw, Daan J; Olivier, Berend; Waldinger, Marcel D

    2009-01-01

    Lifelong premature ejaculation (LPE) is characterized by persistent intravaginal ejaculation latency times (IELTs) of less than 1 minute, and has been postulated as a neurobiological dysfunction with genetic vulnerability for the short IELTs, related to disturbances of central serotonin (5-hydroxytryptamine [5-HT]) neurotransmission and 5-HT receptor functioning. To investigate the relationship between 5-HT transporter gene-linked polymorphism (5-HTTLPR) and short IELTs in men with lifelong PE. A prospective study was conducted in 89 Dutch Caucasian men with lifelong PE. IELT during coitus was assessed by stopwatch over a 1-month period. Controls consisted of 92 Dutch Caucasian men. All men with LPE were genotyped for a 5-HTT-promoter polymorphism. Allele frequencies and genotypes of short (S) and long (L) variants of 5-HTTLPR polymorphism were compared between patients and controls. Association between LL, SL, and SS genotypes, and the natural logarithm of the IELT in men with LPE was investigated. IELT measured by stopwatch, 5-HTTLPR polymorphism. In men with lifelong PE, the geometric mean, median, and natural mean IELTs were 21, 26, and 32 seconds, respectively. There were no significant differences in the 5-HTT polymorphism alleles and genotypes between 89 Dutch Caucasian men with LPE (S 47%, L 53%/LL 29%, SL 48%, SS 22%) and 92 Dutch Caucasian controls (S 48%, L 52%/LL 29%, SL 45%, SS 26%). In men with lifelong PE there was a statistically significant difference between LL, SL, and SS genotypes in their geometric mean IELT (P IELTs than the SS and SL genotypes. The 5-HTTLPR polymorphism is associated with significant effects on the latency to ejaculate in men with lifelong PE. Men with SS and SL genotypes have 100% and 90% longer ejaculation time, respectively than men with LL genotypes.

  4. Philanthropy and disparities: progress, challenges, and unfinished business.

    Science.gov (United States)

    Mitchell, Faith; Sessions, Kathryn

    2011-10-01

    Philanthropy has invested millions of dollars to reduce disparities in health care and improve minority health. Grants to strengthen providers' cultural competence, diversify health professions, and collect data have improved understanding of and spurred action on disparities. The persistence of disparities in spite of these advances has shifted philanthropic attention toward strategies to change social, economic, and environmental conditions. We argue that these evolving perspectives, along with earlier groundwork, present new opportunities for funders, especially in combination with progress toward universal health coverage. This article looks at how philanthropy has addressed health disparities over the past decade, with a focus on accomplishments, the work remaining to be done, and how funders can help advance the disparities agenda.

  5. Thyroid carcinoma after radioiodide therapy for hyperthyroidism. Analysis based on age, latency, and administered dose of I-131

    International Nuclear Information System (INIS)

    Spencer, R.P.; Chapman, C.N.; Rao, H.

    1983-01-01

    Twenty-five reports in the medical literature of thyroid carcinomas which were detected after radioiodide therapy for hyperthyroidism were reviewed. These cases did not show a usual characteristic of radiation-associated tumors, namely a long latency period. That is, in 8/25 the latency period was under five years, and the mean latency was only 7.3 years. Further, there was no relationship between latency and age at treatment, or between latency and the dose of radioiodide employed. In 15/25 of the cases, there were known thyroid nodules. Three of the patients had thyroiditis (which itself has a correlation with thyroid carcinoma), and one individual had prior head and neck external radiation. There was no substantiating evidence that radioiodide treatment for hyperthyroidism was the cause of these thyroid carcinomas

  6. Environmental Health Disparities in Housing

    Science.gov (United States)

    2011-01-01

    The physical infrastructure and housing make human interaction possible and provide shelter. How well that infrastructure performs and which groups it serves have important implications for social equity and health. Populations in inadequate housing are more likely to have environmental diseases and injuries. Substantial disparities in housing have remained largely unchanged. Approximately 2.6 million (7.5%) non-Hispanic Blacks and 5.9 million Whites (2.8%) live in substandard housing. Segregation, lack of housing mobility, and homelessness are all associated with adverse health outcomes. Yet the experience with childhood lead poisoning in the United States has shown that housing-related disparities can be reduced. Effective interventions should be implemented to reduce environmental health disparities related to housing. PMID:21551378

  7. Preterm prelabour rupture of membranes: effect of latency on neonatal and maternal outcomes.

    Science.gov (United States)

    Frenette, Priscilla; Dodds, Linda; Armson, B Anthony; Jangaard, Krista

    2013-08-01

    To compare risks of infection and prematurity-related outcomes according to latency periods among women with preterm prelabour rupture of membranes (PPROM). Women with PPROM occurring between 24+0 and 36+6 weeks of gestation were identified from a provincial population-based perinatal database in Nova Scotia. The primary outcomes included composite variables for serious maternal and neonatal infectious morbidity and neonatal prematurity-related morbidity. Logistic regression was used to quantify the relationship between latency period (prematurity-related morbidity were significantly decreased at the latency periods of 48 hours or more compared with prematurity-related morbidity at 48 hours to prematurity-related morbidity, even close to term, without putting mother or neonate at substantial risk for serious infectious morbidity. Generalization of these findings to other obstetric populations should be informed by the underlying risk of infection.

  8. Memory-dependent adjustment of vocal response latencies in a territorial songbird.

    Science.gov (United States)

    Geberzahn, Nicole; Hultsch, Henrike; Todt, Dietmar

    2013-06-01

    Vocal interactions in songbirds can be used as a model system to investigate the interplay of intrinsic singing programmes (e.g. influences from vocal memories) and external variables (e.g. social factors). When characterizing vocal interactions between territorial rivals two aspects are important: (1) the timing of songs in relation to the conspecific's singing and (2) the use of a song pattern that matches the rival's song. Responses in both domains can be used to address a territorial rival. This study is the first to investigate the relation of the timing of vocal responses to (1) the vocal memory of a responding subject and (2) the selection of the song pattern that the subject uses as a response. To this end, we conducted interactive playback experiments with adult nightingales (Luscinia megarhynchos) that had been hand-reared and tutored in the laboratory. We analysed the subjects' vocal response latencies towards broadcast playback stimuli that they either had in their own vocal repertoire (songs shared with playback) or that they had not heard before (unknown songs). Likewise, we compared vocal response latencies between responses that matched the stimulus song and those that did not. Our findings showed that the latency of singing in response to the playback was shorter for shared versus unknown song stimuli when subjects overlapped the playback stimuli with their own song. Moreover birds tended to overlap faster when vocally matching the stimulus song rather than when replying with a non-matching song type. We conclude that memory of song patterns influenced response latencies and discuss possible mechanisms. Copyright © 2012 Elsevier Ltd. All rights reserved.

  9. Disparity in cancer care: a Canadian perspective

    OpenAIRE

    Ahmed, S.; Shahid, R.K.

    2012-01-01

    Canada is facing cancer crisis. Cancer has become the leading cause of death in Canada. Despite recent advances in cancer management and research, growing disparities in cancer care have been noticed, especially in socio-economically disadvantaged groups and under-served communities. With the rising incidence of cancer and the increasing numbers of minorities and of social disparities in general, and without appropriate interventions, cancer care disparities will become only more pronounced. ...

  10. REGIONAL DISPARITIES – HISTORICAL CULTURAL INFLUENCES AND

    Directory of Open Access Journals (Sweden)

    MARIA OŢIL

    2015-08-01

    Full Text Available In recent decades, the issue of regional disparities has become a highly debated topic, knowledge regarding regional disparities being a matter of political priority as their persistence hinders the appropriate integration process. On the other hand, emphasis was put on integration through the process of EU enlargement, thus highlighting other issues related to the nature and size of disparities. Regional disparities regarding development and the living standards of the population have long been the concern of all Member States. In the case of Romania, recently admitted into the European structures, registering large backlogs to economically developed countries, the intense mobilization of internal and external factors of economic growth in order to reduce and eliminate disparities compared to other countries, represents a clear necessity. The "European Union" (EU project is of an unprecedented complexity and scale because it involves a plurality of states, which are culturally and economically heterogeneous. Moreover, these economic and cultural differences exist even within the states. Hence, there is also the central idea of the Union, regarding unity in diversity. In Romania the local, regional communities have a strong identity, but still evolving. Taking into account Romania's objective of successfully integrating into European structures, and the principles of democratic decision-making requires that regional development should aim at reducing economic and social disparities based on a notable involvement of the local, regional communities. Based on these facts, the paper aims to present the current regional (and intra-regional disparities in Romania with regard to a number of synthetic indicators of capital, of labor and of outcomes. The persistence in time of these economic disparities can be explained by considering the cultural legacies – represented by norms, values, institutions, that impact on how people interact, communicate

  11. Reversible silencing of cytomegalovirus genomes by type I interferon governs virus latency.

    Directory of Open Access Journals (Sweden)

    Franziska Dağ

    2014-02-01

    Full Text Available Herpesviruses establish a lifelong latent infection posing the risk for virus reactivation and disease. In cytomegalovirus infection, expression of the major immediate early (IE genes is a critical checkpoint, driving the lytic replication cycle upon primary infection or reactivation from latency. While it is known that type I interferon (IFN limits lytic CMV replication, its role in latency and reactivation has not been explored. In the model of mouse CMV infection, we show here that IFNβ blocks mouse CMV replication at the level of IE transcription in IFN-responding endothelial cells and fibroblasts. The IFN-mediated inhibition of IE genes was entirely reversible, arguing that the IFN-effect may be consistent with viral latency. Importantly, the response to IFNβ is stochastic, and MCMV IE transcription and replication were repressed only in IFN-responsive cells, while the IFN-unresponsive cells remained permissive for lytic MCMV infection. IFN blocked the viral lytic replication cycle by upregulating the nuclear domain 10 (ND10 components, PML, Sp100 and Daxx, and their knockdown by shRNA rescued viral replication in the presence of IFNβ. Finally, IFNβ prevented MCMV reactivation from endothelial cells derived from latently infected mice, validating our results in a biologically relevant setting. Therefore, our data do not only define for the first time the molecular mechanism of IFN-mediated control of CMV infection, but also indicate that the reversible inhibition of the virus lytic cycle by IFNβ is consistent with the establishment of CMV latency.

  12. Rewards modulate saccade latency but not exogenous spatial attention.

    Science.gov (United States)

    Dunne, Stephen; Ellison, Amanda; Smith, Daniel T

    2015-01-01

    The eye movement system is sensitive to reward. However, whilst the eye movement system is extremely flexible, the extent to which changes to oculomotor behavior induced by reward paradigms persist beyond the training period or transfer to other oculomotor tasks is unclear. To address these issues we examined the effects of presenting feedback that represented small monetary rewards to spatial locations on the latency of saccadic eye movements, the time-course of learning and extinction of the effects of rewarding saccades on exogenous spatial attention and oculomotor inhibition of return. Reward feedback produced a relative facilitation of saccadic latency in a stimulus driven saccade task which persisted for three blocks of extinction trials. However, this hemifield-specific effect failed to transfer to peripheral cueing tasks. We conclude that rewarding specific spatial locations is unlikely to induce long-term, systemic changes to the human oculomotor or attention systems.

  13. Rewards modulate saccade latency but not exogenous spatial attention.

    Directory of Open Access Journals (Sweden)

    Stephen eDunne

    2015-07-01

    Full Text Available The eye movement system is sensitive to reward. However, whilst the eye movement system is extremely flexible, the extent to which changes to oculomotor behaviour induced by reward paradigms persist beyond the training period or transfer to other oculomotor tasks is unclear. To address these issues we examined the effects of presenting feedback that represented small monetary rewards to spatial locations on the latency of saccadic eye movements, the time-course of learning and extinction of the effects of rewarding saccades on exogenous spatial attention and oculomotor IOR. Reward feedback produced a relative facilitation of saccadic latency in a stimulus driven saccade task which persisted for 3 blocks of extinction trials. However this hemifield-specific effect failed to transfer to peripheral cueing tasks. We conclude that rewarding specific spatial locations is unlikely to induce long-term, systemic changes to the human oculomotor or attention systems.

  14. Rural Urban Disparity in and around Surabaya Region, Indonesia

    Directory of Open Access Journals (Sweden)

    Vely Kukinul Siswanto

    2014-12-01

    Full Text Available A shift in development towards the outskirts of urban areas changes the characteristics of the region and can ultimately lead to urban disparities in economic and social terms. The current study has tried to divide the study area covers the areas of surrounding Surabaya as urban, peri urban and rural areas with reference to three time periods (2008, 2009 and 2010 and shows that the typology in the study area changes each year. Furthermore, based on the theil index analysis, using a number of pre-prosperous household for social disparity and per capita GDP (Gross Domestic Product for economic disparity shows that urban and peri urban areas have medium and high level of social and economic disparity compare with rural area which have low levels of disparity. Through multivariate correlation analysis can be seen that the health center distance, electricity and water users effecting the social disparity. Moreover, the financial, industrial, electricity, trade, construction, transportation, agriculture, and mining sector's productivity have a significant relationship with the economic disparity. Health facilities, water and electricity improvement strategies to be followed for reducing the social disparity. Electricity improvement, water, services sector, transportation infrastructure, and industrial development to reduce the economic disparity.

  15. Global stereo matching algorithm based on disparity range estimation

    Science.gov (United States)

    Li, Jing; Zhao, Hong; Gu, Feifei

    2017-09-01

    The global stereo matching algorithms are of high accuracy for the estimation of disparity map, but the time-consuming in the optimization process still faces a curse, especially for the image pairs with high resolution and large baseline setting. To improve the computational efficiency of the global algorithms, a disparity range estimation scheme for the global stereo matching is proposed to estimate the disparity map of rectified stereo images in this paper. The projective geometry in a parallel binocular stereo vision is investigated to reveal a relationship between two disparities at each pixel in the rectified stereo images with different baselines, which can be used to quickly obtain a predicted disparity map in a long baseline setting estimated by that in the small one. Then, the drastically reduced disparity ranges at each pixel under a long baseline setting can be determined by the predicted disparity map. Furthermore, the disparity range estimation scheme is introduced into the graph cuts with expansion moves to estimate the precise disparity map, which can greatly save the cost of computing without loss of accuracy in the stereo matching, especially for the dense global stereo matching, compared to the traditional algorithm. Experimental results with the Middlebury stereo datasets are presented to demonstrate the validity and efficiency of the proposed algorithm.

  16. Auditory brainstem response latency in forward masking, a marker of sensory deficits in listeners with normal hearing thresholds

    DEFF Research Database (Denmark)

    Mehraei, Golbarg; Paredes Gallardo, Andreu; Shinn-Cunningham, Barbara G.

    2017-01-01

    -spontaneous rate fibers results in a faster recovery of wave-V latency as the slow contribution of these fibers is reduced. Results showed that in young audiometrically normal listeners, a larger change in wave-V latency with increasing masker-to-probe interval was related to a greater effect of a preceding masker......-V latency changes with increasing masker-to-probe intervals. In the same listeners, behavioral forward masking detection thresholds were measured. We hypothesized that 1) auditory nerve fiber deafferentation increases forward masking thresholds and increases wave-V latency and 2) a preferential loss of low...

  17. Allometric disparity in rodent evolution

    OpenAIRE

    Wilson LAB

    2013-01-01

    In this study, allometric trajectories for 51 rodent species, comprising equal representatives from each of the major clades (Ctenohystrica, Muroidea, Sciuridae), are compared in a multivariate morphospace (=allometric space) to quantify magnitudes of disparity in cranial growth. Variability in allometric trajectory patterns was compared to measures of adult disparity in each clade, and dietary habit among the examined species, which together encapsulated an ecomorphological breadth. Results ...

  18. Low-Latency Teleoperations for Human Exploration and Evolvable Mars Campaign

    Science.gov (United States)

    Lupisella, Mark; Wright, Michael; Arney, Dale; Gershman, Bob; Stillwagen, Fred; Bobskill, Marianne; Johnson, James; Shyface, Hilary; Larman, Kevin; Lewis, Ruthan; hide

    2015-01-01

    NASA has been analyzing a number of mission concepts and activities that involve low-latency telerobotic (LLT) operations. One mission concept that will be covered in this presentation is Crew-Assisted Sample Return which involves the crew acquiring samples (1) that have already been delivered to space, and or acquiring samples via LLT from orbit to a planetary surface and then launching the samples to space to be captured in space and then returned to the earth with the crew. Both versions of have key roles for low-latency teleoperations. More broadly, the NASA Evolvable Mars Campaign is exploring a number of other activities that involve LLT, such as: (a) human asteroid missions, (b) PhobosDeimos missions, (c) Mars human landing site reconnaissance and site preparation, and (d) Mars sample handling and analysis. Many of these activities could be conducted from Mars orbit and also with the crew on the Mars surface remotely operating assets elsewhere on the surface, e.g. for exploring Mars special regions and or teleoperating a sample analysis laboratory both of which may help address planetary protection concerns. The operational and technology implications of low-latency teleoperations will be explored, including discussion of relevant items in the NASA Technology Roadmap and also how previously deployed robotic assets from any source could subsequently be used by astronauts via LLT.

  19. Health Disparities Calculator (HD*Calc) - SEER Software

    Science.gov (United States)

    Statistical software that generates summary measures to evaluate and monitor health disparities. Users can import SEER data or other population-based health data to calculate 11 disparity measurements.

  20. Energy price disparity and public welfare

    International Nuclear Information System (INIS)

    Templet, P.H.

    2001-01-01

    The differences in the price of energy to economic sectors are linked to a number of system parameters and to public welfare. There are large disparities in energy prices within states when comparing residential and industrial prices although neoclassical economics predicts one price in markets. The large disparities between the two sectors across states negatively affects the efficiency of resource allocation, creates subsidies for those getting the cheap energy and results in unequal access to energy. These in turn lead to inefficient partitioning of energy between products and waste, higher pollution, leakage of wealth and poorer energy use efficiency, i.e. high energy intensity. States with large energy price disparities between sectors have statistically higher poverty, lower incomes, more pollution and use more energy but with less efficiency. Higher energy price disparities also result in higher throughput per unit of output thus reducing the chances for sustainability and lower public welfare. 31 refs

  1. Therapeutic strategies to fight HIV-1 latency: progress and challenges

    CSIR Research Space (South Africa)

    Manoto, Sello L

    2017-10-01

    Full Text Available —1112, 2017 Therapeutic strategies to fight HIV-1 latency: progress and challenges Sello Lebohang Manoto, Lebogang Thobakgale, Rudzani Malabi, Charles Maphanga, Saturnin Ombinda-Lemboumba, Patience Mthunzi-Kufa Abstract: The life...

  2. Luminance, Colour, Viewpoint and Border Enhanced Disparity Energy Model.

    Directory of Open Access Journals (Sweden)

    Jaime A Martins

    Full Text Available The visual cortex is able to extract disparity information through the use of binocular cells. This process is reflected by the Disparity Energy Model, which describes the role and functioning of simple and complex binocular neuron populations, and how they are able to extract disparity. This model uses explicit cell parameters to mathematically determine preferred cell disparities, like spatial frequencies, orientations, binocular phases and receptive field positions. However, the brain cannot access such explicit cell parameters; it must rely on cell responses. In this article, we implemented a trained binocular neuronal population, which encodes disparity information implicitly. This allows the population to learn how to decode disparities, in a similar way to how our visual system could have developed this ability during evolution. At the same time, responses of monocular simple and complex cells can also encode line and edge information, which is useful for refining disparities at object borders. The brain should then be able, starting from a low-level disparity draft, to integrate all information, including colour and viewpoint perspective, in order to propagate better estimates to higher cortical areas.

  3. A Simulation Base Investigation of High Latency Space Systems Operations

    Science.gov (United States)

    Li, Zu Qun; Crues, Edwin Z.; Bielski, Paul; Moore, Michael

    2017-01-01

    NASA's human space program has developed considerable experience with near Earth space operations. Although NASA has experience with deep space robotic missions, NASA has little substantive experience with human deep space operations. Even in the Apollo program, the missions lasted only a few weeks and the communication latencies were on the order of seconds. Human missions beyond the relatively close confines of the Earth-Moon system will involve missions with durations measured in months and communications latencies measured in minutes. To minimize crew risk and to maximize mission success, NASA needs to develop a better understanding of the implications of these types of mission durations and communication latencies on vehicle design, mission design and flight controller interaction with the crew. To begin to address these needs, NASA performed a study using a physics-based subsystem simulation to investigate the interactions between spacecraft crew and a ground-based mission control center for vehicle subsystem operations across long communication delays. The simulation, built with a subsystem modeling tool developed at NASA's Johnson Space Center, models the life support system of a Mars transit vehicle. The simulation contains models of the cabin atmosphere and pressure control system, electrical power system, drinking and waste water systems, internal and external thermal control systems, and crew metabolic functions. The simulation has three interfaces: 1) a real-time crew interface that can be use to monitor and control the vehicle subsystems; 2) a mission control center interface with data transport delays up to 15 minutes each way; 3) a real-time simulation test conductor interface that can be use to insert subsystem malfunctions and observe the interactions between the crew, ground, and simulated vehicle. The study was conducted at the 21st NASA Extreme Environment Mission Operations (NEEMO) mission between July 18th and Aug 3rd of year 2016. The NEEMO

  4. Channel noise effects on first spike latency of a stochastic Hodgkin-Huxley neuron

    Science.gov (United States)

    Maisel, Brenton; Lindenberg, Katja

    2017-02-01

    While it is widely accepted that information is encoded in neurons via action potentials or spikes, it is far less understood what specific features of spiking contain encoded information. Experimental evidence has suggested that the timing of the first spike may be an energy-efficient coding mechanism that contains more neural information than subsequent spikes. Therefore, the biophysical features of neurons that underlie response latency are of considerable interest. Here we examine the effects of channel noise on the first spike latency of a Hodgkin-Huxley neuron receiving random input from many other neurons. Because the principal feature of a Hodgkin-Huxley neuron is the stochastic opening and closing of channels, the fluctuations in the number of open channels lead to fluctuations in the membrane voltage and modify the timing of the first spike. Our results show that when a neuron has a larger number of channels, (i) the occurrence of the first spike is delayed and (ii) the variation in the first spike timing is greater. We also show that the mean, median, and interquartile range of first spike latency can be accurately predicted from a simple linear regression by knowing only the number of channels in the neuron and the rate at which presynaptic neurons fire, but the standard deviation (i.e., neuronal jitter) cannot be predicted using only this information. We then compare our results to another commonly used stochastic Hodgkin-Huxley model and show that the more commonly used model overstates the first spike latency but can predict the standard deviation of first spike latencies accurately. We end by suggesting a more suitable definition for the neuronal jitter based upon our simulations and comparison of the two models.

  5. Health Disparities in Veterans: A Map of the Evidence.

    Science.gov (United States)

    Kondo, Karli; Low, Allison; Everson, Teresa; Gordon, Christine D; Veazie, Stephanie; Lozier, Crystal C; Freeman, Michele; Motu'apuaka, Makalapua; Mendelson, Aaron; Friesen, Mark; Paynter, Robin; Friesen, Caroline; Anderson, Johanna; Boundy, Erin; Saha, Somnath; Quiñones, Ana; Kansagara, Devan

    2017-09-01

    Goals for improving the quality of care for all Veterans and eliminating health disparities are outlined in the Veterans Health Administration Blueprint for Excellence, but the degree to which disparities in utilization, health outcomes, and quality of care affect Veterans is not well understood. To characterize the research on health care disparities in the Veterans Health Administration by means of a map of the evidence. We conducted a systematic search for research studies published from 2006 to February 2016 in MEDLINE and other data sources. We included studies of Veteran populations that examined disparities in 3 outcome categories: utilization, quality of health care, and patient health. We abstracted data on study design, setting, population, clinical area, outcomes, mediators, and presence of disparity for each outcome category. We grouped the data by population characteristics including race, disability status, mental illness, demographics (age, era of service, rural location, and distance from care), sex identity, socioeconomic status, and homelessness, and created maps illustrating the evidence. We reviewed 4249 citations and abstracted data from 351 studies which met inclusion criteria. Studies examining disparities by race/ethnicity comprised by far the vast majority of the literature, followed by studies examining disparities by sex, and mental health condition. Very few studies examined disparities related to lesbian, gay, bisexual, or transgender identity or homelessness. Disparities findings vary widely by population and outcome. Our evidence maps provide a "lay of the land" and identify important gaps in knowledge about health disparities experienced by different Veteran populations.

  6. Disparity modifications and the emotional effects of stereoscopic images

    Science.gov (United States)

    Kawai, Takashi; Atsuta, Daiki; Tomiyama, Yuya; Kim, Sanghyun; Morikawa, Hiroyuki; Mitsuya, Reiko; Häkkinen, Jukka

    2014-03-01

    This paper describes a study that focuses on disparity changes in emotional scenes of stereoscopic (3D) images, in which an examination of the effects on pleasant and arousal was carried out by adding binocular disparity to 2D images that evoke specific emotions, and applying disparity modification based on the disparity analysis of famous 3D movies. From the results of the experiment, for pleasant, a significant difference was found only for the main effect of the emotions. On the other hand, for arousal, there was a trend of increasing the evaluation values in the order 2D condition, 3D condition and 3D condition applied the disparity modification for happiness, surprise, and fear. This suggests the possibility that binocular disparity and the modification affect arousal.

  7. Health Disparities by Income in Spain Before and After the Economic Crisis.

    Science.gov (United States)

    Coveney, Max; García-Gómez, Pilar; Van Doorslaer, Eddy; Van Ourti, Tom

    2016-11-01

    Little is known about how health disparities by income change during times of economic crisis. We apply a decomposition method to unravel the contributions of income growth, income inequality and differential income mobility across socio-demographic groups to changes in health disparities by income in Spain using longitudinal data from the Survey of Income and Living Conditions for the period 2004-2012. We find a modest rise in health inequality by income in Spain in the 5 years of economic growth prior to the start of the crisis in 2008, but a sharp fall after 2008. The drop mainly derives from the fact that loss of employment and earnings has disproportionately affected the incomes of the younger and healthier groups rather than the (mainly stable pension) incomes of the groups over 65 years. This suggests that unequal distribution of income protection by age may reduce health inequality in the short run after an economic recession. Copyright © 2016 John Wiley & Sons, Ltd. Copyright © 2016 John Wiley & Sons, Ltd.

  8. An Ultra-Low-Latency Geo-Routing Scheme for Team-Based Unmanned Vehicular Applications

    KAUST Repository

    Bader, Ahmed

    2016-02-26

    Results and lessons learned from the implementation of a novel ultra low-latency geo-routing scheme are presented in this paper. The geo-routing scheme is intended for team-based mobile systems whereby a cluster of unmanned autonomous vehicles are deployed to accomplish a critical mission under human supervision. The contention-free nature of the developed scheme lends itself to jointly achieve lower latency and higher throughput. Implementation challenges are presented and corresponding resolutions are discussed herewith. © 2015 IEEE.

  9. Characterization of Epstein Barr virus latency pattern in Argentine breast carcinoma.

    Directory of Open Access Journals (Sweden)

    Mario A Lorenzetti

    Full Text Available INTRODUCTION: Epstein-Barr virus (EBV-associated tumors show different expression patterns of latency genes. Since in breast carcinoma this pattern is not yet fully described, our aim was to characterize EBV latency pattern in our EBV positive breast carcinoma series. METHODS: The study was conducted on 71 biopsies of breast carcinoma and in 48 non-neoplastic breast controls. EBNA1, LMP2A and LMP1 expression was assessed by immunohistochemistry with monoclonal antibodies, while viral genomic DNA and EBERs RNA transcripts expression was performed by in situ hybridization. EBV presence was confirmed by PCR. RESULTS: EBV genomic DNA and EBNA1 expression were detected in 31% (22/71 of patients specifically restricted to tumor epithelial cells in breast carcinoma while all breast control samples were negative for both viral DNA and EBNA1 protein. LMP2A was detected in 73% of EBNA1 positive cases, none of which expressed either LMP1 protein or EBERs transcripts. CONCLUSIONS: These findings suggest that EBV expression pattern in the studied biopsies could be different from those previously observed in breast carcinoma cell lines and lead us to suggest a new, EBNA1, LMP2A positive and LMP1 and EBERs negative latency profile in breast carcinoma in our population.

  10. Why the WTA - WTP disparity matters

    Science.gov (United States)

    Brown Thomas C.; Gregory R.

    1999-01-01

    The disparity between willingness to pay (WTP) and willingness to accept compensation (WTA) has been demonstrated repeatedly. Because using WTP estimates of value where a WTA estimate is appropriate tends to undervalue environmental assets, this issue is important to environmental managers. We summarize reasons for the disparity and then discuss some of the...

  11. 34 CFR 222.162 - What disparity standard must a State meet in order to be certified and how are disparities in...

    Science.gov (United States)

    2010-07-01

    ... 34 Education 1 2010-07-01 2010-07-01 false What disparity standard must a State meet in order to be certified and how are disparities in current expenditures or revenues per pupil measured? 222.162... of the Act § 222.162 What disparity standard must a State meet in order to be certified and how are...

  12. GENDER DISPARITIES – ISSUE OF THE CONTEMPORARY SOCIETY?

    Directory of Open Access Journals (Sweden)

    Suzana Demyen

    2016-12-01

    Full Text Available The purpose of this paper is to illustrate the situation of gender disparities in Romania, an important subject of our days, based both on literature review and official data analysis. Since the status of the woman in contemporary society cannot be treated independently from what is largely debated nowadays in relation to the presence of women in different fields on the labor market, we have firstly proceeded to review the main theoretical and empirical literature in this respect. The paper starts with a short introduction in the field, followed by a brief analysis of important data regarding education, wage and hierarchical positions. The second part represents a correlation between the main determinants of the overall progress of society, trying to highlight the main conclusions of this delicate issue

  13. Reduced Disparities in Birth Rates Among Teens

    Science.gov (United States)

    ... Teens Winnable Battles Social Media at CDC Reduced Disparities in Birth Rates among Teens Aged 15–19 ... Pregnancy Prevention Community-Wide Initiative. National Rates and Disparities Nationally, the teen birth rate (number of births ...

  14. Oxaliplatin antagonizes HIV-1 latency by activating NF-κB without causing global T cell activation

    International Nuclear Information System (INIS)

    Zhu, Xiaoli; Liu, Sijie; Wang, Pengfei; Qu, Xiying; Wang, Xiaohui; Zeng, Hanxian; Chen, Huabiao; Zhu, Huanzhang

    2014-01-01

    Highlights: • The chemotherapeutic drug oxaliplatin reactivates latent HIV-1 in this cell line model of HIV-1 latency. • Reactivation is synergized when oxaliplatin is used in combination with valproic acid. • Oxaliplatin reactivates latent HIV-1 through activation of NF-kB and does not induce T cell activation. - Abstract: Reactivation of latent HIV-1 is a promising strategy for the clearance of the viral reservoirs. Because of the limitations of current agents, identification of new latency activators is urgently required. Using an established model of HIV-1 latency, we examined the effect of Oxaliplatin on latent HIV-1 reactivation. We showed that Oxaliplatin, alone or in combination with valproic acid (VPA), was able to reactivate HIV-1 without inducing global T cell activation. We also provided evidence that Oxaliplatin reactivated HIV-1 expression by inducing nuclear factor kappa B (NF-κB) nuclear translocation. Our results indicated that Oxaliplatin could be a potential drug candidate for anti-latency therapies

  15. Oxaliplatin antagonizes HIV-1 latency by activating NF-κB without causing global T cell activation

    Energy Technology Data Exchange (ETDEWEB)

    Zhu, Xiaoli; Liu, Sijie; Wang, Pengfei; Qu, Xiying; Wang, Xiaohui; Zeng, Hanxian [State Key Laboratory of Genetic Engineering, Institute of Genetics, School of Life Sciences, Fudan University, Shanghai 200433 (China); Chen, Huabiao [Ragon Institute of Massachusetts General Hospital, Massachusetts Institute of Technology, and Harvard University, Cambridge, MA 02139 (United States); Zhu, Huanzhang, E-mail: hzzhu@fudan.edu.cn [State Key Laboratory of Genetic Engineering, Institute of Genetics, School of Life Sciences, Fudan University, Shanghai 200433 (China)

    2014-07-18

    Highlights: • The chemotherapeutic drug oxaliplatin reactivates latent HIV-1 in this cell line model of HIV-1 latency. • Reactivation is synergized when oxaliplatin is used in combination with valproic acid. • Oxaliplatin reactivates latent HIV-1 through activation of NF-kB and does not induce T cell activation. - Abstract: Reactivation of latent HIV-1 is a promising strategy for the clearance of the viral reservoirs. Because of the limitations of current agents, identification of new latency activators is urgently required. Using an established model of HIV-1 latency, we examined the effect of Oxaliplatin on latent HIV-1 reactivation. We showed that Oxaliplatin, alone or in combination with valproic acid (VPA), was able to reactivate HIV-1 without inducing global T cell activation. We also provided evidence that Oxaliplatin reactivated HIV-1 expression by inducing nuclear factor kappa B (NF-κB) nuclear translocation. Our results indicated that Oxaliplatin could be a potential drug candidate for anti-latency therapies.

  16. Identifying health disparities across the tobacco continuum.

    Science.gov (United States)

    Fagan, Pebbles; Moolchan, Eric T; Lawrence, Deirdre; Fernander, Anita; Ponder, Paris K

    2007-10-01

    Few frameworks have addressed work-force diversity, inequities and inequalities as part of a comprehensive approach to eliminating tobacco-related health disparities. This paper summarizes the literature and describes the known disparities that exist along the tobacco disease continuum for minority racial and ethnic groups, those living in poverty, those with low education and blue-collar and service workers. The paper also discusses how work-force diversity, inequities in research practice and knowledge allocation and inequalities in access to and quality of health care are fundamental to addressing disparities in health. We examined the available scientific literature and existing public health reports to identify disparities across the tobacco disease continuum by minority racial/ethnic group, poverty status, education level and occupation. Results indicate that differences in risk indicators along the tobacco disease continuum do not explain fully tobacco-related cancer consequences among some minority racial/ethnic groups, particularly among the aggregate groups, blacks/African Americans and American Indians/Alaska Natives. The lack of within-race/ethnic group data and its interactions with socio-economic factors across the life-span contribute to the inconsistency we observe in the disease causal paradigm. More comprehensive models are needed to understand the relationships among disparities, social context, diversity, inequalities and inequities. A systematic approach will also help researchers, practitioners, advocates and policy makers determine critical points for interventions, the types of studies and programs needed and integrative approaches needed to eliminate tobacco-related disparities.

  17. Disparities at the intersection of marginalized groups

    Science.gov (United States)

    Jackson, John W.; Williams, David R.; VanderWeele, Tyler J.

    2016-01-01

    Mental health disparities exist across several dimensions of social inequality, including race/ethnicity, socioeconomic status and gender. Most investigations of health disparities focus on one dimension. Recent calls by researchers argue for studying persons who are marginalized in multiple ways, often from the perspective of intersectionality, a theoretical framework applied to qualitative studies in law, sociology, and psychology. Quantitative adaptations are emerging but there is little guidance as to what measures or methods are helpful. Here, we consider the concept of a joint disparity and its composition, show that this approach can illuminate how outcomes are patterned for social groups that are marginalized across multiple axes of social inequality, and compare the insights gained with that of other measures of additive interaction. We apply these methods to a cohort of males from the National Longitudinal Survey of Youth, examining disparities for black males with low early life SES vs. white males with high early life SES across several outcomes that predict mental health, including unemployment, wages, and incarceration. We report striking disparities in each outcome, but show that the contribution of race, SES, and their intersection varies. PMID:27531592

  18. Social determinants and sexually transmitted disease disparities.

    Science.gov (United States)

    Hogben, Matthew; Leichliter, Jami S

    2008-12-01

    Social determinants of health play an important role in sexually transmitted disease (STD) transmission and acquisition; consequently, racial and ethnic disparities among social determinants are influences upon disparities in STD rates. In this narrative review, we outline a general model showing the relationship between social determinants and STD outcomes, mediated by epidemiologic context. We then review 4 specific social determinants relevant to STD disparities: segregation, health care, socioeconomics and correctional experiences, followed by 2 facets of the resultant epidemiologic context: core areas and sexual networks. This review shows that disparities exist among the social determinants and that they are related to each other, as well as to core areas, sexual networks, and STD rates. Finally, we discuss the implications of our review for STD prevention and control with particular attention to STD program collaboration and service integration.

  19. Communication latencies of Apple push notification messages relevant for delivery of time-critical information to anesthesia providers.

    Science.gov (United States)

    Rothman, Brian S; Dexter, Franklin; Epstein, Richard H

    2013-08-01

    Tablet computers and smart phones have gained popularity in anesthesia departments for educational and patient care purposes. VigiVU(™) is an iOS application developed at Vanderbilt University for remote viewing of perioperative information, including text message notifications delivered via the Apple Push Notification (APN) service. In this study, we assessed the reliability of the APN service. Custom software was written to send a message every minute to iOS devices (iPad(®), iPod Touch(®), and iPhone(®)) via wireless local area network (WLAN) and cellular pathways 24 hours a day over a 4-month period. Transmission and receipt times were recorded and batched by days, with latencies calculated as their differences. The mean, SEM, and the exact 95% upper confidence limits for the percent of days with ≥1 prolonged (>100 seconds) latency were calculated. Acceptable performance was defined as mean latency 100 seconds. Testing conditions included fixed locations of devices in high signal strength locations. Mean latencies were 173,000 iPad and iPod latencies, none were >100 seconds. For iPhone latencies, 0.03% ± 0.01% were >100 seconds. The 95% upper confidence limits of days with ≥1 prolonged latency were 42% (iPhone) and 5% to 8% (iPad, iPod). The APN service was reliable for all studied devices over WLAN and cellular pathways, and performance was better than third party paging systems using Internet connections previously investigated using the same criteria. However, since our study was a best-case assessment, testing is required at individual sites considering use of this technology for critical messaging. Furthermore, since the APN service may fail due to Internet or service provider disruptions, a backup paging system is recommended if the APN service were to be used for critical messaging.

  20. Identification of B cells as a major site for cyprinid herpesvirus 3 latency.

    Science.gov (United States)

    Reed, Aimee N; Izume, Satoko; Dolan, Brian P; LaPatra, Scott; Kent, Michael; Dong, Jing; Jin, Ling

    2014-08-01

    Cyprinid herpesvirus 3 (CyHV-3), commonly known as koi herpesvirus (KHV), is a member of the Alloherpesviridae, and is a recently discovered emerging herpesvirus that is highly pathogenic for koi and common carp. Our previous study demonstrated that CyHV-3 becomes latent in peripheral white blood cells (WBC). In this study, CyHV-3 latency was further investigated in IgM(+) WBC. The presence of the CyHV-3 genome in IgM(+) WBC was about 20-fold greater than in IgM(-) WBC. To determine whether CyHV-3 expressed genes during latency, transcription from all eight open reading frames (ORFs) in the terminal repeat was investigated in IgM(+) WBC from koi with latent CyHV-3 infection. Only a spliced ORF6 transcript was found to be abundantly expressed in IgM(+) WBC from CyHV-3 latently infected koi. The spliced ORF6 transcript was also detected in vitro during productive infection as early as 1 day postinfection. The ORF6 transcript from in vitro infection begins at -127 bp upstream of the ATG codon and ends +188 bp downstream of the stop codon, +20 bp downstream of the polyadenylation signal. The hypothetical protein of ORF6 contains a consensus sequence with homology to a conserved domain of EBNA-3B and ICP4 from Epstein-Barr virus and herpes simplex virus 1, respectively, both members of the Herpesviridae. This is the first report of latent CyHV-3 in B cells and identification of gene transcription during latency for a member of the Alloherpesviridae. This is the first demonstration that a member of the Alloherpesviridae, cyprinid herpesvirus 3 (CyHV-3), establishes a latent infection in the B cells of its host, Cyprinus carpio. In addition, this is the first report of identification of gene transcription during latency for a member of Herpesvirales outside Herpesviridae. This is also the first report that the hypothetical protein of latent transcript of CyHV-3 contains a consensus sequence with homology to a conserved domain of EBNA-3B from Epstein-Barr virus and ICP4

  1. [Prediction of the latency period by cervical ultrasonography in premature rupture of the membranes before term].

    Science.gov (United States)

    Gabriel, R; Morille, C; Drieux, L; Bige, V; Leymarie, F; Quereux, C

    2002-11-01

    To assess the value of ultrasonographic measurement of cervical length for predicting the duration of the latency period from admission to delivery in women with preterm premature rupture of the membranes (PROM). Prospective study in 88 women with preterm PROM before 34 weeks of amenorrhea. The median gestational age at admission was of 30.1 weeks. The clinical management included: no digital examination of the uterine cervix, antenatal corticosteroids, antibiotics (amoxicillin & clavulanic acid) for 7 days, and hoding back until 34 weeks. Cervical length at admission was determined with transvaginal ultrasonography. The duration of the latency period was studied in relation with cervical length, serum C-reactive protein (CRP) level and white blood cell (WBC) count at admission. The median latency period was longer in women with a cervical length > or = 25 mm (10 vs 5 days; p = 0.04), but this was not associated with a significant increase in birth weight. The median latency period was also longer in women with CRP < 20 mg/l (10 vs 3 days; p < 0.001) and this was associated with a significant increase in birth weight (1716 +/- 549 vs 1201 +/- 485 g; p < 0.01). Moreover, increased CRP levels were more frequent in women with a cervical length < 25 mm, and cervical length was no more predictive of the duration of the latency period in the subgroup of women with CRP < 20 mg/l and WBC < 20,000 cells/mm3. In women with preterm PROM, the latency period from admission to delivery is shorter when cervical length is < 25 mm. However, the clinical value of transvaginal ultrasonography is limited in comparison with serum CRP.

  2. Coexistence of enhanced mobile broadband communications and ultra-reliable low-latency communications in mobile front-haul

    Science.gov (United States)

    Ying, Kai; Kowalski, John M.; Nogami, Toshizo; Yin, Zhanping; Sheng, Jia

    2018-01-01

    5G systems are supposed to support coexistence of multiple services such as ultra reliable low latency communications (URLLC) and enhanced mobile broadband (eMBB) communications. The target of eMBB communications is to meet the high-throughput requirement while URLLC are used for some high priority services. Due to the sporadic nature and low latency requirement, URLLC transmission may pre-empt the resource of eMBB transmission. Our work is to analyze the URLLC impact on eMBB transmission in mobile front-haul. Then, some solutions are proposed to guarantee the reliability/latency requirements for URLLC services and minimize the impact to eMBB services at the same time.

  3. Quantifying risk over the life course - latency, age-related susceptibility, and other time-varying exposure metrics.

    Science.gov (United States)

    Wang, Molin; Liao, Xiaomei; Laden, Francine; Spiegelman, Donna

    2016-06-15

    Identification of the latency period and age-related susceptibility, if any, is an important aspect of assessing risks of environmental, nutritional, and occupational exposures. We consider estimation and inference for latency and age-related susceptibility in relative risk and excess risk models. We focus on likelihood-based methods for point and interval estimation of the latency period and age-related windows of susceptibility coupled with several commonly considered exposure metrics. The method is illustrated in a study of the timing of the effects of constituents of air pollution on mortality in the Nurses' Health Study. Copyright © 2016 John Wiley & Sons, Ltd. Copyright © 2016 John Wiley & Sons, Ltd.

  4. Short-Block Protograph-Based LDPC Codes

    Science.gov (United States)

    Divsalar, Dariush; Dolinar, Samuel; Jones, Christopher

    2010-01-01

    Short-block low-density parity-check (LDPC) codes of a special type are intended to be especially well suited for potential applications that include transmission of command and control data, cellular telephony, data communications in wireless local area networks, and satellite data communications. [In general, LDPC codes belong to a class of error-correcting codes suitable for use in a variety of wireless data-communication systems that include noisy channels.] The codes of the present special type exhibit low error floors, low bit and frame error rates, and low latency (in comparison with related prior codes). These codes also achieve low maximum rate of undetected errors over all signal-to-noise ratios, without requiring the use of cyclic redundancy checks, which would significantly increase the overhead for short blocks. These codes have protograph representations; this is advantageous in that, for reasons that exceed the scope of this article, the applicability of protograph representations makes it possible to design highspeed iterative decoders that utilize belief- propagation algorithms.

  5. Efficient Architectures for Low Latency and High Throughput Trading Systems on the JVM

    Directory of Open Access Journals (Sweden)

    Alexandru LIXANDRU

    2013-01-01

    Full Text Available The motivation for our research starts from the common belief that the Java platform is not suitable for implementing ultra-high performance applications. Java is one of the most widely used software development platform in the world, and it provides the means for rapid development of robust and complex applications that are easy to extend, ensuring short time-to-market of initial deliveries and throughout the lifetime of the system. The Java runtime environment, and especially the Java Virtual Machine, on top of which applications are executed, is the principal source of concerns in regards to its suitability in the electronic trading environment, mainly because of its implicit memory management. In this paper, we intend to identify some of the most common measures that can be taken, both at the Java runtime environment level and at the application architecture level, which can help Java applications achieve ultra-high performance. We also propose two efficient architectures for exchange trading systems that allow for ultra-low latencies and high throughput.

  6. A new method to determine reflex latency induced by high rate stimulation of the nervous system

    Directory of Open Access Journals (Sweden)

    Ilhan eKaracan

    2014-07-01

    Full Text Available High rate stimulations of the neuromuscular system, such as continuous whole body vibration, tonic vibration reflex and high frequency electrical stimulation, are used in the physiological research with an increasing interest. In these studies, the neuronal circuitries underlying the reflex responses remain unclear due to the problem of determining the exact reflex latencies. We present a novel cumulated average method to determine the reflex latency during high rate stimulation of the nervous system which was proven to be significantly more accurate than the classical method. The classical method, cumulant density analysis, reveals the relationship between the two synchronously recorded signals as a function of the lag between the signals. The comparison of new method with the classical technique and their relative accuracy was tested using a computer simulation. In the simulated signals the EMG response latency was constructed to be exactly 40 ms. The new method accurately indicated the value of the simulated reflex latency (40 ms. However, the classical method showed that the lag time between the simulated triggers and the simulated signals was 49 ms. Simulation results illustrated that the cumulated average method is a reliable and more accurate method compared with the classical method. We therefore suggest that the new cumulated average method is able to determine the high rate stimulation induced reflex latencies more accurately than the classical method.

  7. Development of the Plate Boundary Observatory GPS Low Latency Salton Trough Radio Network

    Science.gov (United States)

    Walls, C.; Miller, S.; Wilson, B.; Lawrence, S.; Arnitz, E.

    2008-05-01

    UNAVCO is developing a 20 GPS station low latency radio network that spans the San Andreas and San Jacinto faults in the region of highest strain in southern California and the narrowest part of the North America-Pacific plate boundary. The Salton Trough Radio Network (STRN) is instrumented with Ethernet bridge Intuicom EB6+ (900 MHz) radios to transmit a high rate low latency data stream from each permanent GPS site for the purpose of the following: 1) telemeter 15 second data (1 MB/day/station) to the Plate Boundary Observatory archive, 2) accommodate the timely download of 1 and 5 sample per second data following large earthquakes (4 MB/hour/station), and 3) test the UStream of 1Hz BINEX and RTCM data. Three of four phases have been completed. Office radio testing yielded transfer rates of 30-50 KB/s with subsecond latency while streaming 1 Hz data. Latency climbed to ~1.8 seconds while simultaneously streaming 1 Hz and downloading hourly 1 and 5 sample per second data files. Field testing demonstrated rates on the order of 30 KB/s. At present the radios are installed and have transfer rates of 10-40 KB/s between sites that span 10-32 km. The final phase will be the installation of the main telemetry relay where master radios will be connected to a high speed ISP near the town of Brawley. The high-rate low latency UStream data will be available to researchers who are developing prototype earthquake early warning systems in Southern California. A goal of the STRN is to make the data available rapidly enough for GPS-derived coseismic and dynamic displacements to be integrated into early warning system earthquake models. The improved earthquake models will better assist emergency response. UStream data will also aid surveyors who wish to use PBO GPS stations as permanent, high-quality base stations in real-time kinematic surveys.

  8. Health Psychology special series on health disparities

    NARCIS (Netherlands)

    Kazak, A.E.; Bosch, J.; Klonoff, E.A.

    2012-01-01

    With the initiation of this new ongoing special series in Health Psychology on health disparities, we will publish articles that highlight ways in which health psychology can contribute to understanding and ameliorating these disparities. We welcome articles for this new special series and

  9. The Depsipeptide Romidepsin Reverses HIV-1 Latency In Vivo.

    Directory of Open Access Journals (Sweden)

    Ole S Søgaard

    2015-09-01

    Full Text Available Pharmacologically-induced activation of replication competent proviruses from latency in the presence of antiretroviral treatment (ART has been proposed as a step towards curing HIV-1 infection. However, until now, approaches to reverse HIV-1 latency in humans have yielded mixed results. Here, we report a proof-of-concept phase Ib/IIa trial where 6 aviremic HIV-1 infected adults received intravenous 5 mg/m2 romidepsin (Celgene once weekly for 3 weeks while maintaining ART. Lymphocyte histone H3 acetylation, a cellular measure of the pharmacodynamic response to romidepsin, increased rapidly (maximum fold range: 3.7–7.7 relative to baseline within the first hours following each romidepsin administration. Concurrently, HIV-1 transcription quantified as copies of cell-associated un-spliced HIV-1 RNA increased significantly from baseline during treatment (range of fold-increase: 2.4–5.0; p = 0.03. Plasma HIV-1 RNA increased from <20 copies/mL at baseline to readily quantifiable levels at multiple post-infusion time-points in 5 of 6 patients (range 46–103 copies/mL following the second infusion, p = 0.04. Importantly, romidepsin did not decrease the number of HIV-specific T cells or inhibit T cell cytokine production. Adverse events (all grade 1–2 were consistent with the known side effects of romidepsin. In conclusion, romidepsin safely induced HIV-1 transcription resulting in plasma HIV-1 RNA that was readily detected with standard commercial assays demonstrating that significant reversal of HIV-1 latency in vivo is possible without blunting T cell-mediated immune responses. These finding have major implications for future trials aiming to eradicate the HIV-1 reservoir.clinicaltrials.gov NTC02092116.

  10. Characterization of herpes simplex virus type 2 latency-associated transcription in human sacral ganglia and in cell culture.

    Science.gov (United States)

    Croen, K D; Ostrove, J M; Dragovic, L; Straus, S E

    1991-01-01

    The ability of herpes simplex virus type 2 (HSV-2) to establish latency in and reactivate from sacral dorsal root sensory ganglia is the basis for recurrent genital herpes. The expression of HSV-2 genes in latently infected human sacral ganglia was investigated by in situ hybridization. Hybridizations with a probe from the long repeat region of HSV-2 revealed strong nuclear signals overlying neurons in sacral ganglia from five of nine individuals. The RNA detected overlaps with the transcript for infected cell protein O but in the opposite, or "anti-sense," orientation. These observations mimic those made previously with HSV-1 in human trigeminal ganglia and confirm the recent findings during latency in HSV-2-infected mice and guinea pigs. Northern hybridization of RNA from infected Vero cells showed that an HSV-2 latency-associated transcript was similar in size to the larger (1.85 kb) latency transcript of HSV-1. Thus, HSV-1 and HSV-2 latency in human sensory ganglia are similar, if not identical, in terms of their cellular localization and pattern of transcription.

  11. Latency and bit-error-rate evaluation for radio-over-ethernet in optical fiber front-haul networks

    DEFF Research Database (Denmark)

    Sayadi, Mohammadjavad; Rodríguez, Sebastián; Olmos, Juan José Vegas

    2018-01-01

    evaluate this Ethernet packet as a case of study for RoE applications. The packet is transmitted through different fiber spans, measuring the BER and latency on each case. The system achieves BER values below the FEC limit and a manageable latency. These results serve as a guideline and proof of concept...

  12. Application of a zero-latency whitening filter to compact binary coalescence gravitational-wave searches

    Science.gov (United States)

    Tsukada, Leo; Cannon, Kipp; Hanna, Chad; Keppel, Drew; Meacher, Duncan; Messick, Cody

    2018-05-01

    Joint electromagnetic and gravitational-wave (GW) observation is a major goal of both the GW astronomy and electromagnetic astronomy communities for the coming decade. One way to accomplish this goal is to direct follow-up of GW candidates. Prompt electromagnetic emission may fade quickly, therefore it is desirable to have GW detection happen as quickly as possible. A leading source of latency in GW detection is the whitening of the data. We examine the performance of a zero-latency whitening filter in a detection pipeline for compact binary coalescence (CBC) GW signals. We find that the filter reproduces signal-to-noise ratio (SNR) sufficiently consistent with the results of the original high-latency and phase-preserving filter for both noise and artificial GW signals (called "injections"). Additionally, we demonstrate that these two whitening filters show excellent agreement in χ2 value, a discriminator for GW signals.

  13. Molecular control of HIV-1 postintegration latency: implications for the development of new therapeutic strategies

    Directory of Open Access Journals (Sweden)

    Van Lint Carine

    2009-12-01

    Full Text Available Abstract The persistence of HIV-1 latent reservoirs represents a major barrier to virus eradication in infected patients under HAART since interruption of the treatment inevitably leads to a rebound of plasma viremia. Latency establishes early after infection notably (but not only in resting memory CD4+ T cells and involves numerous host and viral trans-acting proteins, as well as processes such as transcriptional interference, RNA silencing, epigenetic modifications and chromatin organization. In order to eliminate latent reservoirs, new strategies are envisaged and consist of reactivating HIV-1 transcription in latently-infected cells, while maintaining HAART in order to prevent de novo infection. The difficulty lies in the fact that a single residual latently-infected cell can in theory rekindle the infection. Here, we review our current understanding of the molecular mechanisms involved in the establishment and maintenance of HIV-1 latency and in the transcriptional reactivation from latency. We highlight the potential of new therapeutic strategies based on this understanding of latency. Combinations of various compounds used simultaneously allow for the targeting of transcriptional repression at multiple levels and can facilitate the escape from latency and the clearance of viral reservoirs. We describe the current advantages and limitations of immune T-cell activators, inducers of the NF-κB signaling pathway, and inhibitors of deacetylases and histone- and DNA- methyltransferases, used alone or in combinations. While a solution will not be achieved by tomorrow, the battle against HIV-1 latent reservoirs is well- underway.

  14. Tap Arduino: An Arduino microcontroller for low-latency auditory feedback in sensorimotor synchronization experiments.

    Science.gov (United States)

    Schultz, Benjamin G; van Vugt, Floris T

    2016-12-01

    Timing abilities are often measured by having participants tap their finger along with a metronome and presenting tap-triggered auditory feedback. These experiments predominantly use electronic percussion pads combined with software (e.g., FTAP or Max/MSP) that records responses and delivers auditory feedback. However, these setups involve unknown latencies between tap onset and auditory feedback and can sometimes miss responses or record multiple, superfluous responses for a single tap. These issues may distort measurements of tapping performance or affect the performance of the individual. We present an alternative setup using an Arduino microcontroller that addresses these issues and delivers low-latency auditory feedback. We validated our setup by having participants (N = 6) tap on a force-sensitive resistor pad connected to the Arduino and on an electronic percussion pad with various levels of force and tempi. The Arduino delivered auditory feedback through a pulse-width modulation (PWM) pin connected to a headphone jack or a wave shield component. The Arduino's PWM (M = 0.6 ms, SD = 0.3) and wave shield (M = 2.6 ms, SD = 0.3) demonstrated significantly lower auditory feedback latencies than the percussion pad (M = 9.1 ms, SD = 2.0), FTAP (M = 14.6 ms, SD = 2.8), and Max/MSP (M = 15.8 ms, SD = 3.4). The PWM and wave shield latencies were also significantly less variable than those from FTAP and Max/MSP. The Arduino missed significantly fewer taps, and recorded fewer superfluous responses, than the percussion pad. The Arduino captured all responses, whereas at lower tapping forces, the percussion pad missed more taps. Regardless of tapping force, the Arduino outperformed the percussion pad. Overall, the Arduino is a high-precision, low-latency, portable, and affordable tool for auditory experiments.

  15. The sequence of cortical activity inferred by response latency variability in the human ventral pathway of face processing.

    Science.gov (United States)

    Lin, Jo-Fu Lotus; Silva-Pereyra, Juan; Chou, Chih-Che; Lin, Fa-Hsuan

    2018-04-11

    Variability in neuronal response latency has been typically considered caused by random noise. Previous studies of single cells and large neuronal populations have shown that the temporal variability tends to increase along the visual pathway. Inspired by these previous studies, we hypothesized that functional areas at later stages in the visual pathway of face processing would have larger variability in the response latency. To test this hypothesis, we used magnetoencephalographic data collected when subjects were presented with images of human faces. Faces are known to elicit a sequence of activity from the primary visual cortex to the fusiform gyrus. Our results revealed that the fusiform gyrus showed larger variability in the response latency compared to the calcarine fissure. Dynamic and spectral analyses of the latency variability indicated that the response latency in the fusiform gyrus was more variable than in the calcarine fissure between 70 ms and 200 ms after the stimulus onset and between 4 Hz and 40 Hz, respectively. The sequential processing of face information from the calcarine sulcus to the fusiform sulcus was more reliably detected based on sizes of the response variability than instants of the maximal response peaks. With two areas in the ventral visual pathway, we show that the variability in response latency across brain areas can be used to infer the sequence of cortical activity.

  16. Rural Health Disparities

    Science.gov (United States)

    ... in the Delta Region for specific data. U.S. – Mexico Border While life expectancy in many counties of ... documents the successes, challenges, and relevant information for planning. ... on rural/urban disparities see What sources cover health behaviors and ...

  17. HIV Reactivation from Latency after Treatment Interruption Occurs on Average Every 5-8 Days--Implications for HIV Remission.

    Directory of Open Access Journals (Sweden)

    Mykola Pinkevych

    2015-07-01

    Full Text Available HIV infection can be effectively controlled by anti-retroviral therapy (ART in most patients. However therapy must be continued for life, because interruption of ART leads to rapid recrudescence of infection from long-lived latently infected cells. A number of approaches are currently being developed to 'purge' the reservoir of latently infected cells in order to either eliminate infection completely, or significantly delay the time to viral recrudescence after therapy interruption. A fundamental question in HIV research is how frequently the virus reactivates from latency, and thus how much the reservoir might need to be reduced to produce a prolonged antiretroviral-free HIV remission. Here we provide the first direct estimates of the frequency of viral recrudescence after ART interruption, combining data from four independent cohorts of patients undergoing treatment interruption, comprising 100 patients in total. We estimate that viral replication is initiated on average once every ≈6 days (range 5.1- 7.6 days. This rate is around 24 times lower than previous thought, and is very similar across the cohorts. In addition, we analyse data on the ratios of different 'reactivation founder' viruses in a separate cohort of patients undergoing ART-interruption, and estimate the frequency of successful reactivation to be once every 3.6 days. This suggests that a reduction in the reservoir size of around 50-70-fold would be required to increase the average time-to-recrudescence to about one year, and thus achieve at least a short period of anti-retroviral free HIV remission. Our analyses suggests that time-to-recrudescence studies will need to be large in order to detect modest changes in the reservoir, and that macaque models of SIV latency may have much higher frequencies of viral recrudescence after ART interruption than seen in human HIV infection. Understanding the mean frequency of recrudescence from latency is an important first step in

  18. Challenges for Multilevel Health Disparities Research in a Transdisciplinary Environment

    Science.gov (United States)

    Holmes, John H.; Lehman, Amy; Hade, Erinn; Ferketich, Amy K.; Sarah, Gehlert; Rauscher, Garth H.; Abrams, Judith; Bird, Chloe E.

    2008-01-01

    Numerous factors play a part in health disparities. Although health disparities are manifested at the level of the individual, other contexts should be considered when investigating the associations of disparities with clinical outcomes. These contexts include families, neighborhoods, social organizations, and healthcare facilities. This paper reports on health disparities research as a multilevel research domain from the perspective of a large national initiative. The Centers for Population Health and Health Disparities (CPHHD) program was established by the NIH to examine the highly dimensional, complex nature of disparities and their effects on health. Because of its inherently transdisciplinary nature, the CPHHD program provides a unique environment in which to perform multilevel health disparities research. During the course of the program, the CPHHD centers have experienced challenges specific to this type of research. The challenges were categorized along three axes: sources of subjects and data, data characteristics, and multilevel analysis and interpretation. The CPHHDs collectively offer a unique example of how these challenges are met; just as importantly, they reveal a broad range of issues that health disparities researchers should consider as they pursue transdisciplinary investigations in this domain, particularly in the context of a large team science initiative. PMID:18619398

  19. First-spike latency in Hodgkin's three classes of neurons.

    Science.gov (United States)

    Wang, Hengtong; Chen, Yueling; Chen, Yong

    2013-07-07

    We study the first-spike latency (FSL) in Hodgkin's three classes of neurons with the Morris-Lecar neuron model. It is found that all the three classes of neurons can encode an external stimulus into FSLs. With DC inputs, the FSLs of all of the neurons decrease with input intensity. With input current decreased to the threshold, class 1 neurons show an arbitrary long FSL whereas class 2 and 3 neurons exhibit the short-limit FSLs. When the input current is sinusoidal, the amplitude, frequency and initial phase can be encoded by all the three classes of neurons. The FSLs of all of the neurons decrease with the input amplitude and frequency. When the input frequency is too high, all of the neurons respond with infinite FSLs. When the initial phase increases, the FSL decreases and then jumps to a maximal value and finally decreases linearly. With changes in the input parameters, the FSLs of the class 1 and 2 neurons exhibit similar properties. However, the FSL of the class 3 neurons became slightly longer and only produces responses for a narrow range of initial phase if input frequencies are low. Moreover, our results also show that the FSL and firing rate responses are mutually independent processes and that neurons can encode an external stimulus into different FSLs and firing rates simultaneously. This finding is consistent with the current theory of dual or multiple complementary coding mechanisms. Copyright © 2013 Elsevier Ltd. All rights reserved.

  20. Perspectives of Orthopedic Surgeons on Racial/Ethnic Disparities in Care.

    Science.gov (United States)

    Adelani, Muyibat A; O'Connor, Mary I

    2017-08-01

    Racial/ethnic disparities in healthcare, including orthopedics, have been extensively documented. However, the level of knowledge among orthopedic surgeons regarding racial/ethnic disparities is unknown. The purpose of this study is to determine the views of orthopedic surgeons on (1) the extent of racial/ethnic disparities in orthopedic care, (2) patient and system factors that may contribute, and (3) the potential role of orthopedic surgeons in the reduction of disparities. Three hundred five members of the American Orthopaedic Association completed a survey to assess their knowledge of racial/ethnic disparities and their perceptions about the underlying causes. Twelve percent of respondents believe that patients often receive different care based on race/ethnicity in healthcare in general, while 9 % believe that differences exist in orthopedic care in general, 3 % believe that differences exist within their hospitals/clinics, and 1 % reported differences in their own practices. Despite this, 68 % acknowledge that there is evidence of disparities in orthopedic care. Fifty-one percent believe that a lack of insurance significantly contributes to disparities. Thirty-five percent believe that diversification of the orthopedic workforce would be a "very effective" strategy in addressing disparities, while 25 % percent believe that research would be "very effective" and 24 % believe that surgeon education would be "very effective." Awareness regarding racial/ethnic disparities in musculoskeletal care is low among orthopedic surgeons. Additionally, respondents were more likely to acknowledge disparities within the practices of others than their own. Increased diversity, research, and education may help improve knowledge of this problem.

  1. Global health disparities: crisis in the diaspora.

    Science.gov (United States)

    Cox, Raymond L.

    2004-01-01

    The United States spends more than the rest of the world on healthcare. In 2000, the U.S. health bill was 1.3 trillion dollars, 14.5% of its gross domestic product. Yet, according to the WHO World Health Report 2000, the United States ranked 37th of 191 member nations in overall health system performance. Racial/ethnic disparities in health outcomes are the most obvious examples of an unbalanced healthcare system. This presentation will examine health disparities in the United States and reveal how health disparities among and within countries affect the health and well-being of the African Diaspora. PMID:15101675

  2. Involvement of histone methyltransferase GLP in HIV-1 latency through catalysis of H3K9 dimethylation

    International Nuclear Information System (INIS)

    Ding, Donglin; Qu, Xiying; Li, Lin; Zhou, Xin; Liu, Sijie; Lin, Shiguan; Wang, Pengfei; Liu, Shaohui; Kong, Chuijin; Wang, Xiaohui; Liu, Lin; Zhu, Huanzhang

    2013-01-01

    Understanding the mechanism of HIV-1 latency is crucial to eradication of the viral reservoir in HIV-1-infected individuals. However, the role of histone methyltransferase (HMT) G9a-like protein (GLP) in HIV-1 latency is still unclear. In the present work, we established four clonal cell lines containing HIV-1 vector. We found that the integration sites of most clonal cell lines favored active gene regions. However, we also observed hypomethylation of CpG of HIV 5′LTR in all four clonal cell lines. Additionally, 5′-deoxy-5′-methylthioadenosine (MTA), a broad-spectrum histone methyltransferase inhibitor, was used to examine the role of histone methylation in HIV-1 latency. MTA was found to decrease the level of H3K9 dimethylation, causing reactivation of latent HIV-1 in C11 cells. GLP knockdown by small interfering RNA clearly induced HIV-1 LTR expression. Results suggest that GLP may play a significant role in the maintenance of HIV-1 latency by catalyzing dimethylation of H3K9. - Highlights: ► We have established an in vitro model of HIV-1 latency. ► The integration sites of most clonal cell lines favor in active gene regions. ► Hypomethylation occurs in CpG islands of HIV 5′LTR in all four clonal cell lines. ► MTA can reactivate latent HIV-1 by decreasing the level of H3K9 me2 in C11 cells. ► HMT GLP may play a significant role in the maintenance of HIV-1 latency

  3. Gender and regional disparities of tuberculosis in Hunan, China.

    Science.gov (United States)

    Chen, Mengshi; Kwaku, Abuaku Benjamin; Chen, Youfang; Huang, Xin; Tan, Hongzhuan; Wen, Shi Wu

    2014-04-27

    Major efforts have been made to improve the health care system in Hunan province, China. The aims of this study were to assess whether and to what extent these efforts have impacted on gender and regional disparities of Tuberculosis (TB) incidence in recent years, especially for less developed areas. We obtained data from the 2005-2009 China Information System for Disease Control and Prevention (CISDCP)to conduct this study in Hunan province. Counties within the province were divided into four regions according to quartiles based on the 2007 per capita GDP. Index of Disparity (ID) and Relative Index of Inequality (RII) were used to measure the disparities of TB incidence in relation to gender and region. Bootstrap technique was used to increase the precision. The average annual incidence of TB was 111.75 per 100,000 in males and 43.44 per 100 000 in females in Hunan. The gender disparity was stable, with ID from 42.34 in 2005 to 43.92 in 2009. For regional disparity, ID, RII (mean) and RII (ratio) decreased significantly from 2005 to 2009 in males (P China, regional disparity in relation to incidence of TB decreased significantly, but the gender disparity remains in the Hunan province.

  4. Stigma and Racial/Ethnic HIV Disparities: Moving toward Resilience

    Science.gov (United States)

    Earnshaw, Valerie A.; Bogart, Laura M.; Dovidio, John F.; Williams, David R.

    2013-01-01

    Prior research suggests that stigma plays a role in racial/ethnic health disparities. However, there is limited understanding about the mechanisms by which stigma contributes to HIV-related disparities in risk, incidence and screening, treatment, and survival and what can be done to reduce the impact of stigma on these disparities. We introduce…

  5. The role of latency period in quality management for free-breathing coronary wall MRI.

    Science.gov (United States)

    Lin, Kai; Lloyd-Jones, Donald M; Liu, Ying; Bi, Xiaoming; Lu, Biao; Li, Debiao; Carr, James C

    2015-03-01

    The aim of the present study was to determine the effects of the latency period on the performance of free-breathing coronary wall MRI. With the approval of IRB, 70 participants were recruited for coronary wall magnetic resonance imaging (MRI) and provided written informed consent. In 35 subjects, right coronary segments (RCA1-3) were imaged first; in the remaining subjects, the left coronary segments (LM and LAD1-3) were imaged first. The images were classified into groups; group 1 contained right coronary images from the subjects whose right coronary segments were imaged first and left coronary images from the subjects whose left coronary segments were imaged first. Group 2 contained the other coronary segments. The image scores (ranked1-3), latency periods, drift of the position of the navigator (NAV), scan efficiency were compared between image groups. Image group 1 has higher scores (1.66 ± 0.55 vs. 1.46 ± 0.51), shorter latency periods (32.04 ± 4.24 vs. 44.22 ± 5.57 min), lower drift in the location of the NAV (1.90 ± 1.27 mm vs. 2.61 ± 1.71 mm) and higher scan efficiency (32.7 ± 7.6 vs. 29.9 ± 7.9%) than group 2. Long latency periods have a significantly negative impact on the image quality of coronary wall MRI.

  6. Predictive factors for latency period in viable pregnancies complicated by preterm premature rupture of the membranes.

    Science.gov (United States)

    Çetin, Cihan; Büyükkurt, Selim; Cömert, Ercan; Özlü, Ferda; Bahar, Nilgün; Demir, Cansun

    2015-03-01

    In this study, we aimed to evaluate some laboratory and clinical factors in the prediction of latency period for pregnant patients complicated with preterm premature rupture of the membranes. Sixty-five pregnant patients between 24 and 34 weeks of gestation, who were admitted to University of Çukurova School of Medicine Hospital with the diagnosis of preterm premature rupture of the membranes (PPROM) between January 01, 2013 and December 31, 2013, were included in this study. Serum CRP, procalcitonin, sedimentation rate, leukocyte count and cervical length (measured with transvaginal ultrasound) of patients were analyzed for the correlation with the latency period. None of the parameters were found to be correlated with the latency period. However, patients with cervical length of premature rupture of the membranes is thought to be either an infection-based disease or a disease increasing the risk of infectious complications, major infection markers are not found to be helpful criteria for the prediction of latency period. Patients with a cervical length of <25 mm can be expected to deliver earlier and, therefore, can be referred to a tertiary center earlier.

  7. Quantifying Risk Over the Life Course – Latency, Age-Related Susceptibility, and Other Time-Varying Exposure Metrics

    Science.gov (United States)

    Wang, Molin; Liao, Xiaomei; Laden, Francine; Spiegelman, Donna

    2016-01-01

    Identification of the latency period and age-related susceptibility, if any, is an important aspect of assessing risks of environmental, nutritional and occupational exposures. We consider estimation and inference for latency and age-related susceptibility in relative risk and excess risk models. We focus on likelihood-based methods for point and interval estimation of the latency period and age-related windows of susceptibility coupled with several commonly considered exposure metrics. The method is illustrated in a study of the timing of the effects of constituents of air pollution on mortality in the Nurses’ Health Study. PMID:26750582

  8. CLAS: A Novel Communications Latency Based Authentication Scheme

    Directory of Open Access Journals (Sweden)

    Zuochao Dou

    2017-01-01

    Full Text Available We design and implement a novel communications latency based authentication scheme, dubbed CLAS, that strengthens the security of state-of-the-art web authentication approaches by leveraging the round trip network communications latency (RTL between clients and authenticators. In addition to the traditional credentials, CLAS profiles RTL values of clients and uses them to defend against password compromise. The key challenges are (i to prevent RTL manipulation, (ii to alleviate network instabilities, and (iii to address mobile clients. CLAS addresses the first challenge by introducing a novel network architecture, which makes it extremely difficult for attackers to simulate legitimate RTL values. The second challenge is addressed by outlier removal and multiple temporal profiling, while the last challenge is addressed by augmenting CLAS with out-of-band-channels or other authentication schemes. CLAS restricts login to profiled locations while demanding additional information for nonprofiled ones, which highly reduces the attack surface even when the legitimate credentials are compromised. Additionally, unlike many state-of-the-art authentication mechanisms, CLAS is resilient to phishing, pharming, man-in-the-middle, and social engineering attacks. Furthermore, CLAS is transparent to users and incurs negligible overhead. The experimental results show that CLAS can achieve very low false positive and false negative rates.

  9. A quantitative measurement of binocular color fusion limit for different disparities

    Science.gov (United States)

    Chen, Zaiqing; Shi, Junsheng; Tai, Yonghan; Huang, Xiaoqiao; Yun, Lijun; Zhang, Chao

    2018-01-01

    Color asymmetry is a common phenomenon in stereoscopic display system, which can cause visual fatigue or visual discomfort. When the color difference between the left and right eyes exceeds a threshold value, named binocular color fusion limit, color rivalry is said to occur. The most important information brought by stereoscopic displays is the depth perception produced by the disparity. As the stereo pair stimuli are presented separately to both eyes with disparities and those two monocular stimuli differ in color but share an iso-luminance polarity, it is possible for stereopsis and color rivalry to coexist. In this paper, we conducted an experiment to measure the color fusion limit for different disparity levels. In particular, it examines how the magnitude and sign of disparity affect the binocular color fusion limit that yields a fused, stable stereoscopic percept. The binocular color fusion limit was measured at five levels of disparities: 0, +/-60, +/-120 arc minutes for a sample color point which was selected from the 1976 CIE u'v' chromaticity diagram. The experimental results showed that fusion limit for the sample point varied with the level and sign of disparity. It was an interesting result that the fusion limit increased as the disparity decreases at crossed disparity direction (sign -), but there is almost no big change at uncrossed disparity direction (sign +). We found that color fusion was more difficult to achieve at the crossed disparity direction than at the uncrossed disparity direction.

  10. Racial/Ethnic Disparities in Mental Health Care Utilization among U.S. College Students: Applying the Institution of Medicine Definition of Health Care Disparities.

    Science.gov (United States)

    Hunt, Justin B; Eisenberg, Daniel; Lu, Liya; Gathright, Molly

    2015-10-01

    The authors apply the Institute of Medicine's definition of health care disparities to college students. The analysis pools data from the first two waves of the Healthy Minds Study, a multicampus survey of students' mental health (N = 13,028). A probit model was used for any past-year service utilization, and group differences in health status were adjusted by transforming the entire distribution for each minority population to approximate the white distribution. Disparities existed between whites and all minority groups. Compared to other approaches, the predicted service disparities were greater because this method included the effects of mediating SES variables. Health care disparities persist in the college setting despite improved access and nearly universal insurance coverage. Our findings emphasize the importance of investigating potential sources of disparities beyond geography and coverage.

  11. Mobile Low Latency Services in 5G

    DEFF Research Database (Denmark)

    Cattoni, Andrea Fabio; Chandramouli, Devaki; Sartori, Cinzia

    2015-01-01

    Networks beyond 2020 will experience 10000-fold increase in wireless traffic, connect 10-100 times more devices and support the most diverse use cases. Thus, the 5G architecture needs to be flexible and cater for both traffic volumes and diversity of service requirements. Among the set of new use...... cases, support of delay sensitive "mobile" applications, such as vehicular communications (V2X, where X stands for either Vehicle or Infrastructure), require architecture enhancements to natively offer low latency and high mobility. In this paper we propose the necessary technology enablers...

  12. Two-level modulation scheme to reduce latency for optical mobile fronthaul networks.

    Science.gov (United States)

    Sung, Jiun-Yu; Chow, Chi-Wai; Yeh, Chien-Hung; Chang, Gee-Kung

    2016-10-31

    A system using optical two-level orthogonal-frequency-division-multiplexing (OFDM) - amplitude-shift-keying (ASK) modulation is proposed and demonstrated to reduce the processing latency for the optical mobile fronthaul networks. At the proposed remote-radio-head (RRH), the high data rate OFDM signal does not need to be processed, but is directly launched into a high speed photodiode (HSPD) and subsequently emitted by an antenna. Only a low bandwidth PD is needed to recover the low data rate ASK control signal. Hence, it is simple and provides low-latency. Furthermore, transporting the proposed system over the already deployed optical-distribution-networks (ODNs) of passive-optical-networks (PONs) is also demonstrated with 256 ODN split-ratios.

  13. Short-latency afferent inhibition is a poor predictor of individual susceptibility to rTMS-induced plasticity in the motor cortex of young and older adults.

    Directory of Open Access Journals (Sweden)

    Marielle eYoung-Bernier

    2014-08-01

    Full Text Available Cortical plasticity, including long-term potentiation (LTP-like plasticity, can be assessed non-invasively with repetitive transcranial magnetic stimulation (rTMS protocols. In this study, we examined age differences in responses to intermittent theta burst stimulation (iTBS in a group of 20 young and 18 healthy older adults. Because the cholinergic system plays a role in the neural processes underlying learning and memory, including LTP, we also investigated whether short latency afferent inhibition (SAI, a neurophysiological marker of central cholinergic activity, would be associated with age-related differences in LTP-like plasticity induced by iTBS. Methods: SAI was first assessed by examining the modulation of motor evoked potentials (MEPs in response to median nerve conditioning 20 ms prior to TMS. Participants then underwent iTBS (3 pulses at 50 HZ every 200 ms for 2 s with 8 s between trains, repeated 20 times. MEP responses (120% RMT were assessed immediately after iTBS and 5, 10, and 20 min post-application. Results: Responses to iTBS were quite variable in both age groups, with only approximately 60% of the participants (n=13 young and 10 older adults showing the expected facilitation of MEP responses. There were no significant age group differences in MEP facilitation following iTBS. Although older adults exhibited reduced SAI, individual variations were not associated with susceptibility to express LTP-like induced plasticity after iTBS. Conclusion: Overall, these results are consistent with reports of high inter-individual variability in responses to iTBS. Although SAI was reduced in older adults, consistent with a deterioration of the cholinergic system with age, SAI levels were not associated with LTP-like plasticity as assessed with iTBS.

  14. Short-latency afferent inhibition is a poor predictor of individual susceptibility to rTMS-induced plasticity in the motor cortex of young and older adults.

    Science.gov (United States)

    Young-Bernier, Marielle; Tanguay, Annick N; Davidson, Patrick S R; Tremblay, François

    2014-01-01

    Cortical plasticity, including long-term potentiation (LTP)-like plasticity, can be assessed non-invasively with repetitive transcranial magnetic stimulation (rTMS) protocols. In this study, we examined age differences in responses to intermittent theta burst stimulation (iTBS) in a group of 20 young and 18 healthy older adults. Because the cholinergic system plays a role in the neural processes underlying learning and memory, including LTP, we also investigated whether short latency afferent inhibition (SAI), a neurophysiological marker of central cholinergic activity, would be associated with age-related differences in LTP-like plasticity induced by iTBS. SAI was first assessed by examining the modulation of motor evoked potentials (MEPs) in response to median nerve conditioning 20 ms prior to TMS. Participants then underwent iTBS (3 pulses at 50 Hz every 200 ms for 2 s with 8 s between trains, repeated 20 times). MEP responses (120% resting motor threshold (RMT)) were assessed immediately after iTBS and 5, 10, and 20 min post-application. Responses to iTBS were quite variable in both age groups, with only approximately 60% of the participants (n = 13 young and 10 older adults) showing the expected facilitation of MEP responses. There were no significant age group differences in MEP facilitation following iTBS. Although older adults exhibited reduced SAI, individual variations were not associated with susceptibility to express LTP-like induced plasticity after iTBS. Overall, these results are consistent with reports of high inter-individual variability in responses to iTBS. Although SAI was reduced in older adults, consistent with a deterioration of the cholinergic system with age, SAI levels were not associated with LTP-like plasticity as assessed with iTBS.

  15. Decomposing Racial/Ethnic Disparities in Influenza Vaccination among the Elderly

    Science.gov (United States)

    Yoo, Byung-Kwang; Hasebe, Takuya; Szilagyi, Peter G.

    2015-01-01

    While persistent racial/ethnic disparities in influenza vaccination have been reported among the elderly, characteristics contributing to disparities are poorly understood. This study aimed to assess characteristics associated with racial/ethnic disparities in influenza vaccination using a nonlinear Oaxaca-Blinder decomposition method. We performed cross-sectional multivariable logistic regression analyses for which the dependent variable was self-reported receipt of influenza vaccine during the 2010–2011 season among community dwelling non-Hispanic African-American (AA), non-Hispanic White (W), English-speaking Hispanic (EH) and Spanish-speaking Hispanic (SH) elderly, enrolled in the 2011 Medicare Current Beneficiary Survey (MCBS) (un-weighted/weighted N= 6,095/19.2million). Using the nonlinear Oaxaca-Blinder decomposition method, we assessed the relative contribution of seventeen covariates—including socio-demographic characteristics, health status, insurance, access, preference regarding healthcare, and geographic regions —to disparities in influenza vaccination. Unadjusted racial/ethnic disparities in influenza vaccination were 14.1 percentage points (pp) (W-AA disparity, p.8). The Oaxaca-Blinder decomposition method estimated that the unadjusted W-AA and W-SH disparities in vaccination could be reduced by only 45% even if AA and SH groups become equivalent to Whites in all covariates in multivariable regression models. The remaining 55% of disparities were attributed to (a) racial/ethnic differences in the estimated coefficients (e.g., odds ratios) in the regression models and (b) characteristics not included in the regression models. Our analysis found that only about 45% of racial/ethnic disparities in influenza vaccination among the elderly could be reduced by equalizing recognized characteristics among racial/ethnic groups. Future studies are needed to identify additional modifiable characteristics causing disparities in influenza vaccination. PMID

  16. Double sliding-window technique: a new method to calculate the neuronal response onset latency.

    Science.gov (United States)

    Berényi, Antal; Benedek, György; Nagy, Attila

    2007-10-31

    Neuronal response onset latency provides important data on the information processing within the central nervous system. In order to enhance the quality of the onset latency estimation, we have developed a 'double sliding-window' technique, which combines the advantages of mathematical methods with the reliability of standard statistical processes. This method is based on repetitive series of statistical probes between two virtual time windows. The layout of the significance curve reveals the starting points of changes in neuronal activity in the form of break-points between linear segments. A second-order difference function is applied to determine the position of maximum slope change, which corresponds to the onset of the response. In comparison with Poisson spike-train analysis, the cumulative sum technique and the method of Falzett et al., this 'double sliding-window, technique seems to be a more accurate automated procedure to calculate the response onset latency of a broad range of neuronal response characteristics.

  17. Epidemiology, Policy, and Racial/Ethnic Minority Health Disparities

    Science.gov (United States)

    Carter-Pokras, Olivia; Offutt-Powell, Tabatha; Kaufman, Jay S.; Giles, Wayne; Mays, Vickie

    2013-01-01

    Purpose Epidemiologists have long contributed to policy efforts to address health disparities. Three examples illustrate how epidemiologists have addressed health disparities in the U.S. and abroad through a “social determinants of health” lens. Methods To identify examples of how epidemiologic research has been applied to reduce health disparities, we queried epidemiologists engaged in disparities research in the U.S., Canada, and New Zealand, and drew upon the scientific literature. Results Resulting examples covered a wide range of topic areas. Three areas selected for their contributions to policy were: 1) epidemiology's role in definition and measurement, 2) the study of housing and asthma, and 3) the study of food policy strategies to reduce health disparities. While epidemiologic research has done much to define and quantify health inequalities, it has generally been less successful at producing evidence that would identify targets for health equity intervention. Epidemiologists have a role to play in measurement and basic surveillance, etiologic research, intervention research, and evaluation research. However, our training and funding sources generally place greatest emphasis on surveillance and etiologic research. Conclusions: The complexity of health disparities requires better training for epidemiologists to effectively work in multidisciplinary teams. Together we can evaluate contextual and multilevel contributions to disease and study intervention programs in order to gain better insights into evidenced-based health equity strategies. PMID:22626003

  18. Compounds producing an effective combinatorial regimen for disruption of HIV-1 latency.

    Science.gov (United States)

    Hashemi, Pargol; Barreto, Kris; Bernhard, Wendy; Lomness, Adam; Honson, Nicolette; Pfeifer, Tom A; Harrigan, P Richard; Sadowski, Ivan

    2018-02-01

    Highly active antiretroviral therapy (HAART) has improved the outlook for the HIV epidemic, but does not provide a cure. The proposed "shock-and-kill" strategy is directed at inducing latent HIV reservoirs, which may then be purged via boosted immune response or targeting infected cells. We describe five novel compounds that are capable of reversing HIV latency without affecting the general T-cell activation state. The new compounds exhibit synergy for reactivation of latent provirus with other latency-reversing agents (LRAs), in particular ingenol-3-angelate/PEP005. One compound, designated PH02, was efficient at reactivating viral transcription in several cell lines bearing reporter HIV-1 at different integration sites. Furthermore, it was capable of reversing latency in resting CD4 + T lymphocytes from latently infected aviremic patient cells on HAART, while producing minimal cellular toxicity. The combination of PH02 and PEP005 produces a strong synergistic effect for reactivation, as demonstrated through a quantitative viral outgrowth assay (qVOA), on CD4 + T lymphocytes from HIV-1-infected individuals. We propose that the PH02/PEP005 combination may represent an effective novel treatment for abrogating persistent HIV-1 infection. © 2017 The Authors. Published under the terms of the CC BY 4.0 license.

  19. Racial Disparities in Palliative Care for Prostate Cancer

    Science.gov (United States)

    2016-01-01

    1 | P a g e Award Number: W81XWH-10-1-0802 TITLE: " Racial Disparities in Palliative Care for Prostate Cancer." PRINCIPAL INVESTIGATOR: Alfred I...CONTRACT NUMBER W81XWH-10-1-0802 " Racial Disparities in Palliative Care for Prostate Cancer." 5b. GRANT NUMBER PC094372 5c. PROGRAM ELEMENT NUMBER...developed the tools/methods for working with SEER-Medicare. We plan to use analytic approaches and methods to explore racial disparities in the use of

  20. Procedure to measure real time latency using software defined radio in a W-band fiber-wireless link

    DEFF Research Database (Denmark)

    Rico-Martínez, Mónica; Morales, Alvaro; Mehmeri, Victor

    2017-01-01

    Reducing latency is a major challenge for current telecommunications systems. 5G networks are envisioned to achieve end-to-end latencies below 1 ms, thus enabling the Internet of Things (IoT) evolution and new applications such as Tactile Internet. In this article, we present a new procedure...

  1. Rein: Taming Tail Latency in Key-Value Stores via Multiget Scheduling

    KAUST Repository

    Reda, Waleed; Canini, Marco; Suresh, Lalith; Kostić, Dejan; Braithwaite, Sean

    2017-01-01

    the composition of aggregate requests and by carefully scheduling bottleneck operations that can otherwise create excessive queues. We design and implement a system called Rein, which reduces latency via inter-multiget scheduling using low overhead techniques. We

  2. Shrapnel: Latency, Mourning and the Suicide of a Parent

    Science.gov (United States)

    Bisagni, Francesco

    2012-01-01

    The aim of this paper is to describe some acute responses to the suicide of a parent, through the account of the analytic psychotherapy of a latency child who found the body of his dead father. The acute traumatic responses of the child show that the perceptual apparatus, time and space are subverted, while the functioning of the contact barrier…

  3. Latency modulation of collicular neurons induced by electric stimulation of the auditory cortex in Hipposideros pratti: In vivo intracellular recording.

    Directory of Open Access Journals (Sweden)

    Kang Peng

    Full Text Available In the auditory pathway, the inferior colliculus (IC receives and integrates excitatory and inhibitory inputs from the lower auditory nuclei, contralateral IC, and auditory cortex (AC, and then uploads these inputs to the thalamus and cortex. Meanwhile, the AC modulates the sound signal processing of IC neurons, including their latency (i.e., first-spike latency. Excitatory and inhibitory corticofugal projections to the IC may shorten and prolong the latency of IC neurons, respectively. However, the synaptic mechanisms underlying the corticofugal latency modulation of IC neurons remain unclear. Thus, this study probed these mechanisms via in vivo intracellular recording and acoustic and focal electric stimulation. The AC latency modulation of IC neurons is possibly mediated by pre-spike depolarization duration, pre-spike hyperpolarization duration, and spike onset time. This study suggests an effective strategy for the timing sequence determination of auditory information uploaded to the thalamus and cortex.

  4. Stereo Hysteresis Revisited

    Directory of Open Access Journals (Sweden)

    Christopher Tyler

    2012-05-01

    Full Text Available One of the most fascinating phenomena in stereopsis is the profound hysteresis effect reported by Fender and Julesz (1967, in which the depth percept persisted with increasing disparity long past the point at which depth was recovered with decreasing disparity. To control retinal disparity without vergence eye movements, they stabilized the stimuli on the retinas with an eye tracker. I now report that stereo hysteresis can be observed directly in printed stereograms simply by rotating the image. As the stereo image rotates, the horizontal disparities rotate to become vertical, then horizontal with inverted sign, and then vertical again before returning to the original orientation. The depth shows an interesting popout effect, almost as though the depth was turning on and off rapidly, despite the inherently sinusoidal change in the horizontal disparity vector. This stimulus was generated electronically in a circular format so that the random-dot field could be dynamically replaced, eliminating any cue to cyclorotation. Noise density was scaled with eccentricity to fade out the stimulus near fixation. For both the invariant and the dynamic noise, profound hysteresis of several seconds delay was found in six observers. This was far longer than the reaction time to respond to changes in disparity, which was less than a second. Purely horizontal modulation of disparity to match the horizontal vector component of the disparity rotation did not show the popout effect, which thus seems to be a function of the interaction between horizontal and vertical disparities and may be attributable to depth interpolation processes.

  5. Disparities in Disability by Educational Attainment Across US States.

    Science.gov (United States)

    Montez, Jennifer Karas; Zajacova, Anna; Hayward, Mark D

    2017-07-01

    To examine how disparities in adult disability by educational attainment vary across US states. We used the nationally representative data of more than 6 million adults aged 45 to 89 years in the 2010-2014 American Community Survey. We defined disability as difficulty with activities of daily living. We categorized education as low (less than high school), mid (high school or some college), or high (bachelor's or higher). We estimated age-standardized disability prevalence by educational attainment and state. We assessed whether the variation in disability across states occurs primarily among low-educated adults and whether it reflects the socioeconomic resources of low-educated adults and their surrounding contexts. Disparities in disability by education vary markedly across states-from a 20 percentage point disparity in Massachusetts to a 12-point disparity in Wyoming. Disparities vary across states mainly because the prevalence of disability among low-educated adults varies across states. Personal and contextual socioeconomic resources of low-educated adults account for 29% of the variation. Efforts to reduce disparities in disability by education should consider state and local strategies that reduce poverty among low-educated adults and their surrounding contexts.

  6. Explaining Racial Disparities in Infant Health in Brazil

    Science.gov (United States)

    Nyarko, Kwame A.; Lopez-Camelo, Jorge; Castilla, Eduardo E.

    2015-01-01

    Objectives. We sought to quantify how socioeconomic, health care, demographic, and geographic effects explain racial disparities in low birth weight (LBW) and preterm birth (PTB) rates in Brazil. Methods. We employed a sample of 8949 infants born between 1995 and 2009 in 15 cities and 7 provinces in Brazil. We focused on disparities in LBW (Public policies to improve children’s health should target prenatal care and geographic location differences to reduce health disparities between infants of African and European ancestries in Brazil. PMID:26313046

  7. A high-density ERP study reveals latency, amplitude, and topographical differences in multiple sclerosis patients versus controls.

    LENUS (Irish Health Repository)

    Whelan, R

    2012-02-01

    OBJECTIVE: To quantify latency, amplitude and topographical differences in event-related potential (ERP) components between multiple sclerosis (MS) patients and controls and to compare ERP findings with results from the paced auditory serial addition test (PASAT). METHODS: Fifty-four subjects (17 relapsing remitting (RRMS) patients, 16 secondary progressive (SPMS) patients, and 21 controls) completed visual and auditory oddball tasks while data were recorded from 134 EEG channels. Latency and amplitude differences, calculated using composite mean amplitude measures, were tested using an ANOVA. Topographical differences were tested using statistical parametric mapping (SPM). RESULTS: In the visual modality, P2, P3 amplitudes and N2 latency were significantly different across groups. In the auditory modality, P2, N2, and P3 latencies and N1 amplitude were significantly different across groups. There were no significant differences between RRMS and SPMS patients on any ERP component. There were topographical differences between MS patients and controls for both early and late components for the visual modality, but only in the early components for the auditory modality. PASAT score correlated significantly with auditory P3 latency for MS patients. CONCLUSIONS: There were significant ERP differences between MS patients and controls. SIGNIFICANCE: The present study indicated that both early sensory and later cognitive ERP components are impaired in MS patients relative to controls.

  8. An Approach to Integrating Health Disparities within Undergraduate Biomedical Engineering Education.

    Science.gov (United States)

    Vazquez, Maribel; Marte, Otto; Barba, Joseph; Hubbard, Karen

    2017-11-01

    Health disparities are preventable differences in the incidence, prevalence and burden of disease among communities targeted by gender, geographic location, ethnicity and/or socio-economic status. While biomedical research has identified partial origin(s) of divergent burden and impact of disease, the innovation needed to eradicate health disparities in the United States requires unique engagement from biomedical engineers. Increasing awareness of the prevalence and consequences of health disparities is particularly attractive to today's undergraduates, who have undauntedly challenged paradigms believed to foster inequality. Here, the Department of Biomedical Engineering at The City College of New York (CCNY) has leveraged its historical mission of access-and-excellence to integrate the study of health disparities into undergraduate BME curricula. This article describes our novel approach in a multiyear study that: (i) Integrated health disparities modules at all levels of the required undergraduate BME curriculum; (ii) Developed opportunities to include impacts of health disparities into undergraduate BME research projects and mentored High School summer STEM training; and (iii) Established health disparities-based challenges as BME capstone design and/or independent entrepreneurship projects. Results illustrate the rising awareness of health disparities among the youngest BMEs-to-be, as well as abundant undergraduate desire to integrate health disparities within BME education and training.

  9. A Comparison Between House Mouse Lines Selected for Attack Latency or Nest-Building : Evidence for a Genetic Basis of Alternative Behavioral Strategies

    NARCIS (Netherlands)

    Sluyter, Frans; Bult, Abel; Lynch, Carol B.; Oortmerssen, Geert A. van; Koolhaas, Jaap M.

    House mouse lines bidirectionally selected for either nest-building behavior or attack latency were tested for both attack latency and nest-building behavior under identical conditions. Male mice selected for high nest-building behavior had shorter attack latencies, i.e., were more aggressive, than

  10. A reaction-diffusion model to capture disparity selectivity in primary visual cortex.

    Directory of Open Access Journals (Sweden)

    Mohammed Sultan Mohiuddin Siddiqui

    Full Text Available Decades of experimental studies are available on disparity selective cells in visual cortex of macaque and cat. Recently, local disparity map for iso-orientation sites for near-vertical edge preference is reported in area 18 of cat visual cortex. No experiment is yet reported on complete disparity map in V1. Disparity map for layer IV in V1 can provide insight into how disparity selective complex cell receptive field is organized from simple cell subunits. Though substantial amounts of experimental data on disparity selective cells is available, no model on receptive field development of such cells or disparity map development exists in literature. We model disparity selectivity in layer IV of cat V1 using a reaction-diffusion two-eye paradigm. In this model, the wiring between LGN and cortical layer IV is determined by resource an LGN cell has for supporting connections to cortical cells and competition for target space in layer IV. While competing for target space, the same type of LGN cells, irrespective of whether it belongs to left-eye-specific or right-eye-specific LGN layer, cooperate with each other while trying to push off the other type. Our model captures realistic 2D disparity selective simple cell receptive fields, their response properties and disparity map along with orientation and ocular dominance maps. There is lack of correlation between ocular dominance and disparity selectivity at the cell population level. At the map level, disparity selectivity topography is not random but weakly clustered for similar preferred disparities. This is similar to the experimental result reported for macaque. The details of weakly clustered disparity selectivity map in V1 indicate two types of complex cell receptive field organization.

  11. A comparison of herpes simplex virus type 1 and varicella-zoster virus latency and reactivation.

    Science.gov (United States)

    Kennedy, Peter G E; Rovnak, Joel; Badani, Hussain; Cohrs, Randall J

    2015-07-01

    Herpes simplex virus type 1 (HSV-1; human herpesvirus 1) and varicella-zoster virus (VZV; human herpesvirus 3) are human neurotropic alphaherpesviruses that cause lifelong infections in ganglia. Following primary infection and establishment of latency, HSV-1 reactivation typically results in herpes labialis (cold sores), but can occur frequently elsewhere on the body at the site of primary infection (e.g. whitlow), particularly at the genitals. Rarely, HSV-1 reactivation can cause encephalitis; however, a third of the cases of HSV-1 encephalitis are associated with HSV-1 primary infection. Primary VZV infection causes varicella (chickenpox) following which latent virus may reactivate decades later to produce herpes zoster (shingles), as well as an increasingly recognized number of subacute, acute and chronic neurological conditions. Following primary infection, both viruses establish a latent infection in neuronal cells in human peripheral ganglia. However, the detailed mechanisms of viral latency and reactivation have yet to be unravelled. In both cases latent viral DNA exists in an 'end-less' state where the ends of the virus genome are joined to form structures consistent with unit length episomes and concatemers, from which viral gene transcription is restricted. In latently infected ganglia, the most abundantly detected HSV-1 RNAs are the spliced products originating from the primary latency associated transcript (LAT). This primary LAT is an 8.3 kb unstable transcript from which two stable (1.5 and 2.0 kb) introns are spliced. Transcripts mapping to 12 VZV genes have been detected in human ganglia removed at autopsy; however, it is difficult to ascribe these as transcripts present during latent infection as early-stage virus reactivation may have transpired in the post-mortem time period in the ganglia. Nonetheless, low-level transcription of VZV ORF63 has been repeatedly detected in multiple ganglia removed as close to death as possible. There is increasing

  12. Implementation of a Low-Latency Contention-Free Geographical Routing Scheme for Mobile Cyber-Physical Systems

    KAUST Repository

    Bader, Ahmed

    2015-07-09

    Results and lessons learned from the implementation of a novel ultra low-latency geo-routing scheme are presented in this paper. The geo-routing scheme is intended for team-based mobile cyber-physical systems whereby a cluster of unmanned vehicles (robots) are deployed to accomplish a critical mission under human supervision. The contention-free nature of the developed scheme lends itself to jointly achieve lower latency and higher throughput. Implementation challenges are presented and corresponding resolutions are discussed herewith.

  13. CpG methylation controls reactivation of HIV from latency

    Czech Academy of Sciences Publication Activity Database

    Blažková, Jana; Trejbalová, Kateřina; Gondois-Rey, F.; Halfon, P.; Philibert, P.; Guiguen, A.; Verdin, E.; Olive, D.; Van Lint, C.; Hejnar, Jiří; Hirsch, I.

    2009-01-01

    Roč. 5, č. 8 (2009), e1000554-e1000554 E-ISSN 1553-7374 R&D Projects: GA ČR GA204/05/0939; GA ČR GP204/08/P616 Institutional research plan: CEZ:AV0Z50520514 Keywords : HIV-1 * proviral latency * CpG methylation * histone modifications * HAART * epigenetics Subject RIV: EB - Genetics ; Molecular Biology Impact factor: 8.978, year: 2009

  14. Antibody-independent control of gamma-herpesvirus latency via B cell induction of anti-viral T cell responses.

    Directory of Open Access Journals (Sweden)

    Kelly B McClellan

    2006-06-01

    Full Text Available B cells can use antibody-dependent mechanisms to control latent viral infections. It is unknown whether this represents the sole function of B cells during chronic viral infection. We report here that hen egg lysozyme (HEL-specific B cells can contribute to the control of murine gamma-herpesvirus 68 (gammaHV68 latency without producing anti-viral antibody. HEL-specific B cells normalized defects in T cell numbers and proliferation observed in B cell-/- mice during the early phase of gammaHV68 latency. HEL-specific B cells also reversed defects in CD8 and CD4 T cell cytokine production observed in B cell-/- mice, generating CD8 and CD4 T cells necessary for control of latency. Furthermore, HEL-specific B cells were able to present virally encoded antigen to CD8 T cells. Therefore, B cells have antibody independent functions, including antigen presentation, that are important for control of gamma-herpesvirus latency. Exploitation of this property of B cells may allow enhanced vaccine responses to chronic virus infection.

  15. Racial and ethnic disparities in antidepressant drug use.

    Science.gov (United States)

    Chen, Jie; Rizzo, John A

    2008-12-01

    Little is known about racial and ethnic disparities in health care utilization, expenditures and drug choice in the antidepressant market. This study investigates factors associated with the racial and ethnic disparities in antidepressant drug use. We seek to determine the extent to which disparities reflect differences in observable population characteristics versus heterogeneity across racial and ethnic groups. Among the population characteristics, we are interested in identifying which factors are most important in accounting for racial and ethnic disparities in antidepressant drug use. Using Medical Expenditure Panel Survey (MEPS) data from 1996-2003, we have an available sample of 10,416 Caucasian, 1,089 African American and 1,539 Hispanic antidepressant drug users aged 18 to 64 years. We estimate individual out-of-pocket payments, total prescription drug expenditures, drug utilization, the probability of taking generic versus brand name antidepressants, and the share of drugs that are older types of antidepressants (e.g., TCAs and MAOIs) for these individuals during a calendar year. Blinder-Oaxaca decomposition techniques are employed to determine the extent to which disparities reflect differences in observable population characteristics versus unobserved heterogeneity across racial and ethnic groups. Caucasians have the highest antidepressant drug expenditures and utilization. African-Americans have the lowest drug expenditures and Hispanics have the lowest drug utilization. Relative to Caucasians and Hispanics, African-Americans are more likely to purchase generics and use a higher share of older drugs (e.g., TCAs and MAOIs). Differences in observable characteristics explain most of the racial/ethnic differences in these outcomes, with the exception of drug utilization. Differences in health insurance and education levels are particularly important factors in explaining disparities. In contrast, differences in drug utilization largely reflect unobserved

  16. Low-latency Science Exploration of Planetary Bodies: a Demonstration Using ISS in Support of Mars Human Exploration

    Science.gov (United States)

    Thronson, Harley A.; Valinia, Azita; Bleacher, Jacob; Eigenbrode, Jennifer; Garvin, Jim; Petro, Noah

    2014-01-01

    We summarize a proposed experiment to use the International Space Station to formally examine the application and validation of low-latency telepresence for surface exploration from space as an alternative, precursor, or potentially as an adjunct to astronaut "boots on the ground." The approach is to develop and propose controlled experiments, which build upon previous field studies and which will assess the effects of different latencies (0 to 500 msec), task complexity, and alternate forms of feedback to the operator. These experiments serve as an example of a pathfinder for NASA's roadmap of missions to Mars with low-latency telerobotic exploration as a precursor to astronaut's landing on the surface to conduct geological tasks.

  17. Lifetime and latency analysis of IEEE 802.15.6 WBAN with ...

    Indian Academy of Sciences (India)

    Anil K Jacob

    It is of utmost importance in a wireless body area network (WBAN) to improve the lifetimes of devices, while ... energy efficiency, and latency [3] that the network should provide .... frame transmission by a node, backoff counter of the node is set ...

  18. Upregulation of the Chemokine Receptor CCR2B in Epstein‒Barr Virus-Positive Burkitt Lymphoma Cell Lines with the Latency III Program

    Directory of Open Access Journals (Sweden)

    Svetlana Kozireva

    2018-05-01

    Full Text Available CCR2 is the cognate receptor to the chemokine CCL2. CCR2–CCL2 signaling mediates cancer progression and metastasis dissemination. However, the role of CCR2–CCL2 signaling in pathogenesis of B-cell malignancies is not clear. Previously, we showed that CCR2B was upregulated in ex vivo peripheral blood B cells upon Epstein‒Barr virus (EBV infection and in established lymphoblastoid cell lines with the EBV latency III program. EBV latency III is associated with B-cell lymphomas in immunosuppressed patients. The majority of EBV-positive Burkitt lymphoma (BL tumors are characterized by latency I, but the BL cell lines drift towards latency III during in vitro culture. In this study, the CCR2A and CCR2B expression was assessed in the isogenic EBV-positive BL cell lines with latency I and III using RT-PCR, immunoblotting, and immunostaining analyses. We found that CCR2B is upregulated in the EBV-positive BL cells with latency III. Consequently, we detected the migration of latency III cells toward CCL2. Notably, the G190A mutation, corresponding to SNP CCR2-V64I, was found in one latency III cell line with a reduced migratory response to CCL2. The upregulation of CCR2B may contribute to the enhanced migration of malignant B cells into CCL2-rich compartments.

  19. A fast and reliable method for simultaneous waveform, amplitude and latency estimation of single-trial EEG/MEG data.

    Directory of Open Access Journals (Sweden)

    Wouter D Weeda

    Full Text Available The amplitude and latency of single-trial EEG/MEG signals may provide valuable information concerning human brain functioning. In this article we propose a new method to reliably estimate single-trial amplitude and latency of EEG/MEG signals. The advantages of the method are fourfold. First, no a-priori specified template function is required. Second, the method allows for multiple signals that may vary independently in amplitude and/or latency. Third, the method is less sensitive to noise as it models data with a parsimonious set of basis functions. Finally, the method is very fast since it is based on an iterative linear least squares algorithm. A simulation study shows that the method yields reliable estimates under different levels of latency variation and signal-to-noise ratioÕs. Furthermore, it shows that the existence of multiple signals can be correctly determined. An application to empirical data from a choice reaction time study indicates that the method describes these data accurately.

  20. Why should we investigate the morphological disparity of plant clades?

    Science.gov (United States)

    Oyston, Jack W; Hughes, Martin; Gerber, Sylvain; Wills, Matthew A

    2016-04-01

    Disparity refers to the morphological variation in a sample of taxa, and is distinct from diversity or taxonomic richness. Diversity and disparity are fundamentally decoupled; many groups attain high levels of disparity early in their evolution, while diversity is still comparatively low. Diversity may subsequently increase even in the face of static or declining disparity by increasingly fine sub-division of morphological 'design' space (morphospace). Many animal clades reached high levels of disparity early in their evolution, but there have been few comparable studies of plant clades, despite their profound ecological and evolutionary importance. This study offers a prospective and some preliminary macroevolutionary analyses. Classical morphometric methods are most suitable when there is reasonable conservation of form, but lose traction where morphological differences become greater (e.g. in comparisons across higher taxa). Discrete character matrices offer one means to compare a greater diversity of forms. This study explores morphospaces derived from eight discrete data sets for major plant clades, and discusses their macroevolutionary implications. Most of the plant clades in this study show initial, high levels of disparity that approach or attain the maximum levels reached subsequently. These plant clades are characterized by an initial phase of evolution during which most regions of their empirical morphospaces are colonized. Angiosperms, palms, pines and ferns show remarkably little variation in disparity through time. Conifers furnish the most marked exception, appearing at relatively low disparity in the latest Carboniferous, before expanding incrementally with the radiation of successive, tightly clustered constituent sub-clades. Many cladistic data sets can be repurposed for investigating the morphological disparity of plant clades through time, and offer insights that are complementary to more focused morphometric studies. The unique structural and

  1. CTCF Prevents the Epigenetic Drift of EBV Latency Promoter Qp

    Science.gov (United States)

    Tempera, Italo; Wiedmer, Andreas; Dheekollu, Jayaraju; Lieberman, Paul M.

    2010-01-01

    The establishment and maintenance of Epstein-Barr Virus (EBV) latent infection requires distinct viral gene expression programs. These gene expression programs, termed latency types, are determined largely by promoter selection, and controlled through the interplay between cell-type specific transcription factors, chromatin structure, and epigenetic modifications. We used a genome-wide chromatin-immunoprecipitation (ChIP) assay to identify epigenetic modifications that correlate with different latency types. We found that the chromatin insulator protein CTCF binds at several key regulatory nodes in the EBV genome and may compartmentalize epigenetic modifications across the viral genome. Highly enriched CTCF binding sites were identified at the promoter regions upstream of Cp, Wp, EBERs, and Qp. Since Qp is essential for long-term maintenance of viral genomes in type I latency and epithelial cell infections, we focused on the role of CTCF in regulating Qp. Purified CTCF bound ∼40 bp upstream of the EBNA1 binding sites located at +10 bp relative to the transcriptional initiation site at Qp. Mutagenesis of the CTCF binding site in EBV bacmids resulted in a decrease in the recovery of stable hygromycin-resistant episomes in 293 cells. EBV lacking the Qp CTCF site showed a decrease in Qp transcription initiation and a corresponding increase in Cp and Fp promoter utilization at 8 weeks post-transfection. However, by 16 weeks post-transfection, bacmids lacking CTCF sites had no detectable Qp transcription and showed high levels of histone H3 K9 methylation and CpG DNA methylation at the Qp initiation site. These findings provide direct genetic evidence that CTCF functions as a chromatin insulator that prevents the promiscuous transcription of surrounding genes and blocks the epigenetic silencing of an essential promoter, Qp, during EBV latent infection. PMID:20730088

  2. 78 FR 35837 - National Institute on Minority Health and Health Disparities Research Endowments

    Science.gov (United States)

    2013-06-14

    ... disparities research to close the disparity gap in the burden of illness and death experienced by racial and... Number NIH-2007-0931] RIN 0925-AA61 National Institute on Minority Health and Health Disparities Research... disparities research and other health disparities research. DATES: Comments must be received on or before...

  3. Pemodelan dan Verifikasi Formal Pengaruh Mobility pattern Terhadap Handoff Latency pada Jaringan WiMAX

    Directory of Open Access Journals (Sweden)

    I Nym Saputra Wahyu Wijaya

    2016-01-01

    Full Text Available In order to decrease handoff latency and increase the successful of HHO conventional scheme, a development of handover scheme is done in standard protocol WiMAX IEEE 802.16e by adding mobility pattern. The superiority of handover scheme with mobility pattern can reduce handoff latency up to 50%, mean while the weakness of this scheme is a wrong act in determining target base station are often happen. Simulation can not showing the cause of that error. So, we do formal verification in to hard handover model with mobility pattern.             In this research, behaviour system is modeled with continuous-time Markov chain (CTMC. The model is foccused to aproximating the influence of mobility pattern in to handoff latency from WiMAX hard handover mechanism. In order to set up a series markov chain models handover system can follow steps, such as: represents the state space, give a number in all transitions, generate the rate transition matrix (infinitesimal generator.             Probabilistic model checking in the research are using quantitative properties and qualitative properties. Formal verification concerning properties has relation with handover in WiMAX network showing that 70% from mobile station which doing scanning with mobility pattern are success doing handover. 24% of them doing scanning conventional as a result of wrongness in act determining target base station, so handoff latency which is pictured will bigger than a system that is only use conventional scanning method.

  4. Long latency postural responses are functionally modified by cognitive set.

    Science.gov (United States)

    Beckley, D J; Bloem, B R; Remler, M P; Roos, R A; Van Dijk, J G

    1991-10-01

    We examined how cognitive set influences the long latency components of normal postural responses in the legs. We disturbed the postural stability of standing human subjects with sudden toe-up ankle rotations. To influence the subjects' cognitive set, we varied the rotation amplitude either predictably (serial 4 degrees versus serial 10 degrees) or unpredictably (random mixture of 4 degrees and 10 degrees). The subjects' responses to these ankle rotations were assessed from the EMG activity of the tibialis anterior, the medial gastrocnemius, and the vastus lateralis muscles of the left leg. The results indicate that, when the rotation amplitude is predictable, only the amplitude of the long latency (LL) response in tibialis anterior and vastus lateralis varied directly with perturbation size. Furthermore, when the rotation amplitude is unpredictable, the central nervous system selects a default amplitude for the LL response in the tibialis anterior. When normal subjects are exposed to 2 perturbation amplitudes which include the potential risk of falling, the default LL response in tibialis anterior appropriately anticipates the larger amplitude perturbation rather than the smaller or an intermediate one.

  5. Recurrent connectivity can account for the dynamics of disparity processing in V1

    Science.gov (United States)

    Samonds, Jason M.; Potetz, Brian R.; Tyler, Christopher W.; Lee, Tai Sing

    2013-01-01

    Disparity tuning measured in the primary visual cortex (V1) is described well by the disparity energy model, but not all aspects of disparity tuning are fully explained by the model. Such deviations from the disparity energy model provide us with insight into how network interactions may play a role in disparity processing and help to solve the stereo correspondence problem. Here, we propose a neuronal circuit model with recurrent connections that provides a simple account of the observed deviations. The model is based on recurrent connections inferred from neurophysiological observations on spike timing correlations, and is in good accord with existing data on disparity tuning dynamics. We further performed two additional experiments to test predictions of the model. First, we increased the size of stimuli to drive more neurons and provide a stronger recurrent input. Our model predicted sharper disparity tuning for larger stimuli. Second, we displayed anti-correlated stereograms, where dots of opposite luminance polarity are matched between the left- and right-eye images and result in inverted disparity tuning in the disparity energy model. In this case, our model predicted reduced sharpening and strength of inverted disparity tuning. For both experiments, the dynamics of disparity tuning observed from the neurophysiological recordings in macaque V1 matched model simulation predictions. Overall, the results of this study support the notion that, while the disparity energy model provides a primary account of disparity tuning in V1 neurons, neural disparity processing in V1 neurons is refined by recurrent interactions among elements in the neural circuit. PMID:23407952

  6. Integrating intersectionality and biomedicine in health disparities research.

    Science.gov (United States)

    Kelly, Ursula A

    2009-01-01

    Persisting health disparities have lead to calls for an increase in health research to address them. Biomedical scientists call for research that stratifies individual indicators associated with health disparities, for example, ethnicity. Feminist social scientists recommend feminist intersectionality research. Intersectionality is the multiplicative effect of inequalities experienced by nondominant marginalized groups, for example, ethnic minorities, women, and the poor. The elimination of health disparities necessitates integration of both paradigms in health research. This study provides a practical application of the integration of biomedical and feminist intersectionality paradigms in nursing research, using a psychiatric intervention study with battered Latino women as an example.

  7. Effects of latency period on aspects of the reproductive biology of ...

    African Journals Online (AJOL)

    Heterobranchus longifilisbroodstock were procured, acclimatized and hypophycised with ovaprim. Eggs were stripped from the females between 8 and17 hrs. After hypophysation, while milt was obtained from the males by dissection. Proliferation and ease of flow of eggs were observed as the latency period increased.

  8. Potential improvement of Lymantria dispar L. management by quercetin

    Directory of Open Access Journals (Sweden)

    Perić-Mataruga Vesna

    2014-01-01

    Full Text Available Lymantria dispar, a polyphagous insect pest, copes with a wide variety of host-specific allelochemicals. Glutathione S-transferases (GST are important for catalyzing detoxification in L. dispar. Larval mortality, GST activity in midgut tissue and mass of L. dispar with different trophic adaptations (originating from two forests with a suitable host, Quercus robur, and an unsuitable host, Robinia pseudoacacia, differed after feeding on quercetin supplemented diets (2% or 5% w/w. Quercetin inhibited GST most potently in oak forest larvae that were less adapted to flavonoids in their diet. The larvicidal effect of quercetin on L. dispar larvae depended on the host-use history. We believe this is important in strategies for sustainable control of insect pests. [Projekat Ministarstva nauke Republike Srbije, br. 173027

  9. Fuzzy Logic based Handoff Latency Reduction Mechanism in Layer 2 of Heterogeneous Mobile IPv6 Networks

    Science.gov (United States)

    Anwar, Farhat; Masud, Mosharrof H.; Latif, Suhaimi A.

    2013-12-01

    Mobile IPv6 (MIPv6) is one of the pioneer standards that support mobility in IPv6 environment. It has been designed to support different types of technologies for providing seamless communications in next generation network. However, MIPv6 and subsequent standards have some limitations due to its handoff latency. In this paper, a fuzzy logic based mechanism is proposed to reduce the handoff latency of MIPv6 for Layer 2 (L2) by scanning the Access Points (APs) while the Mobile Node (MN) is moving among different APs. Handoff latency occurs when the MN switches from one AP to another in L2. Heterogeneous network is considered in this research in order to reduce the delays in L2. Received Signal Strength Indicator (RSSI) and velocity of the MN are considered as the input of fuzzy logic technique. This technique helps the MN to measure optimum signal quality from APs for the speedy mobile node based on fuzzy logic input rules and makes a list of interfaces. A suitable interface from the list of available interfaces can be selected like WiFi, WiMAX or GSM. Simulation results show 55% handoff latency reduction and 50% packet loss improvement in L2 compared to standard to MIPv6.

  10. Fuzzy Logic based Handoff Latency Reduction Mechanism in Layer 2 of Heterogeneous Mobile IPv6 Networks

    International Nuclear Information System (INIS)

    Anwar, Farhat; Masud, Mosharrof H; Latif, Suhaimi A

    2013-01-01

    Mobile IPv6 (MIPv6) is one of the pioneer standards that support mobility in IPv6 environment. It has been designed to support different types of technologies for providing seamless communications in next generation network. However, MIPv6 and subsequent standards have some limitations due to its handoff latency. In this paper, a fuzzy logic based mechanism is proposed to reduce the handoff latency of MIPv6 for Layer 2 (L2) by scanning the Access Points (APs) while the Mobile Node (MN) is moving among different APs. Handoff latency occurs when the MN switches from one AP to another in L2. Heterogeneous network is considered in this research in order to reduce the delays in L2. Received Signal Strength Indicator (RSSI) and velocity of the MN are considered as the input of fuzzy logic technique. This technique helps the MN to measure optimum signal quality from APs for the speedy mobile node based on fuzzy logic input rules and makes a list of interfaces. A suitable interface from the list of available interfaces can be selected like WiFi, WiMAX or GSM. Simulation results show 55% handoff latency reduction and 50% packet loss improvement in L2 compared to standard to MIPv6

  11. Usefulness of phrenic latency and forced vital capacity in patients with ALS with latent respiratory dysfunction.

    Science.gov (United States)

    Kwon, Soonwook; Min, Ju-Hong; Cho, Hye-Jin; Joo, Byung-Euk; Cho, Eun Bin; Seok, Jin Myoung; Kim, Min-Ji; Kim, Byoung Joon

    2015-07-01

    The pulmonary function test (PFT) is a non-invasive and easily available technique to assess respiratory function in patients with amyotrophic lateral sclerosis (ALS); however, patients with dyspnea sometimes show normal PFT findings. Herein, we investigated whether phrenic nerve conduction study (NCS) and PFT are useful to evaluate respiratory function of patients with ALS with normal value ranges in the PFT. We prospectively enrolled 34 patients with definite or probable ALS, who showed FVC (%) ⩾80 of predicted and 78 healthy subjects. PFT and phrenic NCS were performed with the measurement of forced vital capacity (FVC, %), forced expiratory volumes in 1s (FEV1, %), FEV1/FCV ratio (%), and phrenic compound muscle action potential amplitude, and latency. Compared to healthy controls, ALS patients showed delayed phrenic nerve latency and the decrease of FVC (%) (p=0.006 and pphrenic latency (AUC=0.7655) and FVC (%) (AUC=0.8239) discriminated ALS patients from healthy subjects. We demonstrated that ALS patients had early respiratory dysfunction, despite normal PFT findings. Phrenic latency and FVC (%) can be helpful to discriminate ALS patients with latent respiratory dysfunction from healthy subjects. Copyright © 2014 International Federation of Clinical Neurophysiology. Published by Elsevier Ireland Ltd. All rights reserved.

  12. Analog Testing of Operations Concepts for Mitigation of Communication Latency During Human Space Exploration

    Science.gov (United States)

    Chappell, Steven P.; Abercromby, Andrew F.; Miller, Matthew J.; Halcon, Christopher; Gernhardt, Michael L.

    2016-01-01

    OBJECTIVES: NASA Extreme Environment Mission Operations (NEEMO) is an underwater spaceflight analog that allows a true mission-like operational environment and uses buoyancy effects and added weight to simulate different gravity levels. Three missions were undertaken from 2014-2015, NEEMO's 18-20. All missions were performed at the Aquarius undersea research habitat. During each mission, the effects of varying operations concepts and tasks type and complexity on representative communication latencies associated with Mars missions were studied. METHODS: 12 subjects (4 per mission) were weighed out to simulate near-zero or partial gravity extravehicular activity (EVA) and evaluated different operations concepts for integration and management of a simulated Earth-based science backroom team (SBT) to provide input and direction during exploration activities. Exploration traverses were planned in advance based on precursor data collected. Subjects completed science-related tasks including presampling surveys, geologic-based sampling, and marine-based sampling as a portion of their tasks on saturation dives up to 4 hours in duration that were to simulate extravehicular activity (EVA) on Mars or the moons of Mars. One-way communication latencies, 5 and 10 minutes between space and mission control, were simulated throughout the missions. Objective data included task completion times, total EVA times, crew idle time, translation time, SBT assimilation time (defined as time available for SBT to discuss data/imagery after it has been collected, in addition to the time taken to watch imagery streaming over latency). Subjective data included acceptability, simulation quality, capability assessment ratings, and comments. RESULTS: Precursor data can be used effectively to plan and execute exploration traverse EVAs (plans included detailed location of science sites, high-fidelity imagery of the sites, and directions to landmarks of interest within a site). Operations concepts that

  13. Stereo Disparity through Cost Aggregation with Guided Filter

    Directory of Open Access Journals (Sweden)

    Pauline Tan

    2014-10-01

    Full Text Available Estimating the depth, or equivalently the disparity, of a stereo scene is a challenging problem in computer vision. The method proposed by Rhemann et al. in 2011 is based on a filtering of the cost volume, which gives for each pixel and for each hypothesized disparity a cost derived from pixel-by-pixel comparison. The filtering is performed by the guided filter proposed by He et al. in 2010. It computes a weighted local average of the costs. The weights are such that similar pixels tend to have similar costs. Eventually, a winner-take-all strategy selects the disparity with the minimal cost for each pixel. Non-consistent labels according to left-right consistency are rejected; a densification step can then be launched to fill the disparity map. The method can be used to solve other labeling problems (optical flow, segmentation but this article focuses on the stereo matching problem.

  14. Disparity Disambiguation by Fusion of Signal and Symbolic-Level Information

    DEFF Research Database (Denmark)

    Ralli, J.; Diaz, J.; Ros, E.

    2012-01-01

    We describe a method for resolving ambiguities in low-level disparity calculations in a stereo-vision scheme by using a recurrent mechanism that we call signal-symbol loop. Due to the local nature of low-level processing it is not always possible to estimate the correct disparity values produced...... at this level. Symbolic abstraction of the signal produces robust, high confidence, multimodal image features which can be used to interpret the scene more accurately and therefore disambiguate low-level interpretations by biasing the correct disparity. The fusion process is capable of producing more accurate...... dense disparity maps than the low- and symbolic-level algorithms can produce independently. Therefore we describe an efficient fusion scheme that allows symbolic- and low-level cues to complement each other, resulting in a more accurate and dense disparity representation of the scene....

  15. Zebra Alphaherpesviruses (EHV-1 and EHV-9: Genetic Diversity, Latency and Co-Infections

    Directory of Open Access Journals (Sweden)

    Azza Abdelgawad

    2016-09-01

    Full Text Available Alphaherpesviruses are highly prevalent in equine populations and co-infections with more than one of these viruses’ strains frequently diagnosed. Lytic replication and latency with subsequent reactivation, along with new episodes of disease, can be influenced by genetic diversity generated by spontaneous mutation and recombination. Latency enhances virus survival by providing an epidemiological strategy for long-term maintenance of divergent strains in animal populations. The alphaherpesviruses equine herpesvirus 1 (EHV-1 and 9 (EHV-9 have recently been shown to cross species barriers, including a recombinant EHV-1 observed in fatal infections of a polar bear and Asian rhinoceros. Little is known about the latency and genetic diversity of EHV-1 and EHV-9, especially among zoo and wild equids. Here, we report evidence of limited genetic diversity in EHV-9 in zebras, whereas there is substantial genetic variability in EHV-1. We demonstrate that zebras can be lytically and latently infected with both viruses concurrently. Such a co-occurrence of infection in zebras suggests that even relatively slow-evolving viruses such as equine herpesviruses have the potential to diversify rapidly by recombination. This has potential consequences for the diagnosis of these viruses and their management in wild and captive equid populations.

  16. An image-warping architecture for VR : low latency versus image quality

    NARCIS (Netherlands)

    Smit, F.A.; Liere, van R.; Beck, S.; Fröhlich, B.; Steed, A.; Reiners, D.; Lindeman, R.W.

    2009-01-01

    Designing low end-to-end latency system architectures for virtual reality is still an open and challenging problem. We describe the design, implementation and evaluation of a client-server depth-image warping architecture that updates and displays the scene graph at the refresh rate of the display.

  17. Literacy and Health Disparities

    Science.gov (United States)

    Prins, Esther; Mooney, Angela

    2014-01-01

    This chapter explores the relationship between literacy and health disparities, focusing on the concept of health literacy. Recommendations are provided for ways to bridge the health literacy gap for learners in adult basic education and family literacy programs.

  18. The association between racial disparity in income and reported sexually transmitted infections.

    Science.gov (United States)

    Owusu-Edusei, Kwame; Chesson, Harrell W; Leichliter, Jami S; Kent, Charlotte K; Aral, Sevgi O

    2013-05-01

    We examined the association between racial disparity in income and reported race-specific county-level bacterial sexually transmitted infections (STIs) in the United States focusing on disparities between Blacks and Whites. Data are from the US 2000 decennial census. We defined 2 race-income county groups (high and low race-income disparity) on the basis of the difference between Black and White median household incomes. We used 2 approaches to examine disparities in STI rates across the groups. In the first approach, we computed and compared race-specific STI rates for the groups. In the second approach, we used spatial regression analyses to control for potential confounders. Consistent with the STI literature, chlamydia, gonorrhea, and syphilis rates for Blacks were substantially higher than were those for Whites. We also found that racial disparities in income were associated with racial disparities in chlamydia and gonorrhea rates and, to a lesser degree, syphilis rates. Racial disparities in household income may be a more important determinant of racial disparities in reported STI morbidity than are absolute levels of household income.

  19. A comparison of herpes simplex virus type 1 and varicella-zoster virus latency and reactivation

    Science.gov (United States)

    Kennedy, Peter G. E.; Rovnak, Joel; Badani, Hussain

    2015-01-01

    Herpes simplex virus type 1 (HSV-1; human herpesvirus 1) and varicella-zoster virus (VZV; human herpesvirus 3) are human neurotropic alphaherpesviruses that cause lifelong infections in ganglia. Following primary infection and establishment of latency, HSV-1 reactivation typically results in herpes labialis (cold sores), but can occur frequently elsewhere on the body at the site of primary infection (e.g. whitlow), particularly at the genitals. Rarely, HSV-1 reactivation can cause encephalitis; however, a third of the cases of HSV-1 encephalitis are associated with HSV-1 primary infection. Primary VZV infection causes varicella (chickenpox) following which latent virus may reactivate decades later to produce herpes zoster (shingles), as well as an increasingly recognized number of subacute, acute and chronic neurological conditions. Following primary infection, both viruses establish a latent infection in neuronal cells in human peripheral ganglia. However, the detailed mechanisms of viral latency and reactivation have yet to be unravelled. In both cases latent viral DNA exists in an ‘end-less’ state where the ends of the virus genome are joined to form structures consistent with unit length episomes and concatemers, from which viral gene transcription is restricted. In latently infected ganglia, the most abundantly detected HSV-1 RNAs are the spliced products originating from the primary latency associated transcript (LAT). This primary LAT is an 8.3 kb unstable transcript from which two stable (1.5 and 2.0 kb) introns are spliced. Transcripts mapping to 12 VZV genes have been detected in human ganglia removed at autopsy; however, it is difficult to ascribe these as transcripts present during latent infection as early-stage virus reactivation may have transpired in the post-mortem time period in the ganglia. Nonetheless, low-level transcription of VZV ORF63 has been repeatedly detected in multiple ganglia removed as close to death as possible. There is

  20. Discrete Serotonin Systems Mediate Memory Enhancement and Escape Latencies after Unpredicted Aversive Experience in Drosophila Place Memory

    Directory of Open Access Journals (Sweden)

    Divya Sitaraman

    2017-12-01

    Full Text Available Feedback mechanisms in operant learning are critical for animals to increase reward or reduce punishment. However, not all conditions have a behavior that can readily resolve an event. Animals must then try out different behaviors to better their situation through outcome learning. This form of learning allows for novel solutions and with positive experience can lead to unexpected behavioral routines. Learned helplessness, as a type of outcome learning, manifests in part as increases in escape latency in the face of repeated unpredicted shocks. Little is known about the mechanisms of outcome learning. When fruit fly Drosophilamelanogaster are exposed to unpredicted high temperatures in a place learning paradigm, flies both increase escape latencies and have a higher memory when given control of a place/temperature contingency. Here we describe discrete serotonin neuronal circuits that mediate aversive reinforcement, escape latencies, and memory levels after place learning in the presence and absence of unexpected aversive events. The results show that two features of learned helplessness depend on the same modulatory system as aversive reinforcement. Moreover, changes in aversive reinforcement and escape latency depend on local neural circuit modulation, while memory enhancement requires larger modulation of multiple behavioral control circuits.

  1. A low-latency, low-overhead encoder for data transmission in the ATLAS Liquid Argon Calorimeter trigger upgrade

    Energy Technology Data Exchange (ETDEWEB)

    Xiao, Le [Department of Physics, Central China Normal University, Wuhan, Hubei 430079 (China); Department of Physics, Southern Methodist University, Dallas, TX 75275 (United States); Li, Xiaoting [Department of Physics, Central China Normal University, Wuhan, Hubei 430079 (China); Gong, Datao, E-mail: dgong@mail.smu.edu [Department of Physics, Southern Methodist University, Dallas, TX 75275 (United States); Chen, Jinghong [Department of Electrical and Computer Engineering, University of Houston, Houston, TX 77004 (United States); Deng, Binwei [School of Electric and Electronic Information Engineering, Hubei Polytechnic University, Huangshi, Hubei 435003 (China); Fan, Qingjun; Feng, Yulang [Department of Electrical and Computer Engineering, University of Houston, Houston, TX 77004 (United States); Guo, Di [Department of Physics, Southern Methodist University, Dallas, TX 75275 (United States); State Key Laboratory of Particle Detection and Electronics, University of Science and Technology of China, Hefei, Anhui 230026 (China); He, Huiqin [Department of Physics, Central China Normal University, Wuhan, Hubei 430079 (China); Department of Physics, Southern Methodist University, Dallas, TX 75275 (United States); Shenzhen Polytechnic, Shenzhen 518055 (China); Hou, Suen [Institute of Physics, Academia Sinica, Nangang 11529, Taipei, Taiwan (China); Huang, Guangming, E-mail: gmhuang@phy.ccnu.edu.cn [Department of Physics, Central China Normal University, Wuhan, Hubei 430079 (China); Liu, Chonghan; Liu, Tiankuan [Department of Physics, Southern Methodist University, Dallas, TX 75275 (United States); Sun, Xiangming [Department of Physics, Central China Normal University, Wuhan, Hubei 430079 (China); Tang, Yuxuan [Department of Electrical and Computer Engineering, University of Houston, Houston, TX 77004 (United States); Teng, Ping-Kun [Institute of Physics, Academia Sinica, Nangang 11529, Taipei, Taiwan (China); and others

    2016-09-21

    In this paper, we present the design and test results of an encoder integrated circuit for the ATLAS Liquid Argon Calorimeter trigger upgrade. The encoder implements a low-latency and low-overhead line code called LOCic. The encoder operates at 320 MHz with a latency of no greater than 21 ns. The overhead of the encoder is 14.3%. The encoder is an important block of the transmitter ASIC LOCx2, which is prototyped with a commercial 0.25 μm Silicon-on-Sapphire CMOS technology and packaged in a 100-pin QFN package. - Highlights: • We present the design and test results of an encoder integrated circuit for the ATLAS Liquid Argon Calorimeter trigger upgrade. • The encoder implements a low-latency and low-overhead line code called LOCic. The encoder operates at 320 MHz with a latency of no greater than 21 ns. The overhead of the encoder is 14.3%. • The encoder is an important block of the transmitter ASIC LOCx2, which is prototyped with a commercial 0.25 μm Silicon-on-Sapphire CMOS technology for radiation-tolerance and packaged in a 100-pin QFN package.

  2. CDC Health Disparities and Inequalities Report--U.S. 2013

    Science.gov (United States)

    ... Women's Health Health Literacy Health Equity CDC Health Disparities & Inequalities Report (CHDIR) Recommend on Facebook Tweet Share ... 2011 Report More Information CDC Releases Second Health Disparities & Inequalities Report - United States, 2013 CDC and its ...

  3. Maturation of long latency auditory evoked potentials in hearing children: systematic review.

    Science.gov (United States)

    Silva, Liliane Aparecida Fagundes; Magliaro, Fernanda Cristina Leite; Carvalho, Ana Claudia Martinho de; Matas, Carla Gentile

    2017-05-15

    To analyze how Auditory Long Latency Evoked Potentials (LLAEP) change according to age in children population through a systematic literature review. After formulation of the research question, a bibliographic survey was done in five data bases with the following descriptors: Electrophysiology (Eletrofisiologia), Auditory Evoked Potentials (Potenciais Evocados Auditivos), Child (Criança), Neuronal Plasticity (Plasticidade Neuronal) and Audiology (Audiologia). Level 1 evidence articles, published between 1995 and 2015 in Brazilian Portuguese or English language. Aspects related to emergence, morphology and latency of P1, N1, P2 and N2 components were analyzed. A total of 388 studies were found; however, only 21 studies contemplated the established criteria. P1 component is characterized as the most frequent component in young children, being observed around 100-150 ms, which tends to decrease as chronological age increases. The N2 component was shown to be the second most commonly observed component in children, being observed around 200-250 ms.. The other N1 and P2 components are less frequent and begin to be seen and recorded throughout the maturational process. The maturation of LLAEP occurs gradually, and the emergence of P1, N1, P2 and N2 components as well as their latency values are variable in childhood. P1 and N2 components are the most observed and described in pediatric population. The diversity of protocols makes the comparison between studies difficult.

  4. NEEMO 18-20: Analog Testing for Mitigation of Communication Latency During Human Space Exploration

    Science.gov (United States)

    Chappell, Steven P.; Beaton, Kara H.; Miller, Matthew J.; Graff, Trevor G.; Abercromby, Andrew F. J.; Gernhardt, Michael L.; Halcon, Christopher

    2016-01-01

    NASA Extreme Environment Mission Operations (NEEMO) is an underwater spaceflight analog that allows a true mission-like operational environment and uses buoyancy effects and added weight to simulate different gravity levels. Three missions were undertaken from 2014-2015, NEEMO's 18-20. All missions were performed at the Aquarius undersea research habitat. During each mission, the effects of communication latencies on operations concepts, timelines, and tasks were studied. METHODS: Twelve subjects (4 per mission) were weighed out to simulate near-zero or partial gravity extravehicular activity (EVA) and evaluated different operations concepts for integration and management of a simulated Earth-based science team (ST) to provide input and direction during exploration activities. Exploration traverses were preplanned based on precursor data. Subjects completed science-related tasks including pre-sampling surveys, geologic-based sampling, and marine-based sampling as a portion of their tasks on saturation dives up to 4 hours in duration that were designed to simulate extravehicular activity (EVA) on Mars or the moons of Mars. One-way communication latencies, 5 and 10 minutes between space and mission control, were simulated throughout the missions. Objective data included task completion times, total EVA times, crew idle time, translation time, ST assimilation time (defined as time available for ST to discuss data/imagery after data acquisition). Subjective data included acceptability, simulation quality, capability assessment ratings, and comments. RESULTS: Precursor data can be used effectively to plan and execute exploration traverse EVAs (plans included detailed location of science sites, high-fidelity imagery of the sites, and directions to landmarks of interest within a site). Operations concepts that allow for pre-sampling surveys enable efficient traverse execution and meaningful Mission Control Center (MCC) interaction across communication latencies and can be

  5. [Decrease in N170 evoked potential component latency during repeated presentation of face images].

    Science.gov (United States)

    Verkhliutov, V M; Ushakov, V L; Strelets, V B

    2009-01-01

    The 15 healthy volunteers EEG from 28 channels was recorded during the presentation of visual stimuli in the form of face and building images. The stimuli were presented in two series. The first series consisted of 60 face and 60 building images presented in random order. The second series consisted of 30 face and 30 building images. The second series began 1.5-2 min after the end of the first ore. No instruction was given to the participants. P1, N170 and VPP EP components were identified for both stimuli categories. These components were located in the medial parietal area (Brodmann area 40). P1 and N170 components were recorded in the superior temporal fissure (Brodmann area 21, STS region), the first component had the latency 120 ms, the second one--155 ms. VPP was recorded with the latency 190 ms (Brodmann area 19). Dynamic mapping of EP components with the latency from 97 to 242 ms revealed the removal of positive maximums from occipital to frontal areas through temporal ones and their subsequent returning to occipital areas through the central ones. During the comparison of EP components to face and building images the amplitude differences were revealed in the following areas: P1--in frontal, central and anterior temporal areas, N170--in frontal, central, temporal and parietal areas, VPP--in all areas. It was also revealed that N170 latency was 12 ms shorter for face than for building images. It was proposed that the above mentioned N170 latency decrease for face in comparison with building images is connected with the different space location of the fusiform area responsible for face and building images recognition. Priming--the effect that is revealed during the repetitive face images presentation is interpreted as the manifestation of functional heterogeneity of the fusiform area responsible for the face images recognition. The hypothesis is put forward that the parts of extrastriate cortex which are located closer to the central retinotopical

  6. Gender Disparity in Education Enrollment in Pakistan

    OpenAIRE

    Shakil Quayes; Richard David Ramsey

    2015-01-01

    The paper examines the determinants of school enrollment in Pakistan. The likelihood of school enrollment is estimated using separate logistic regression models for three different age groups. The empirical results indicate severe gender disparity in school enrollment across all age groups, particularly among the older age groups. Although the rate of school enrollment is positively associated with household income, the gender disparity actually deteriorates with an increase in household inco...

  7. Mind the gap: race/ethnic and socioeconomic disparities in obesity.

    Science.gov (United States)

    Krueger, Patrick M; Reither, Eric N

    2015-11-01

    Race/ethnic and socioeconomic status (SES) disparities in obesity are substantial and may widen in the future. We review nine potential mechanisms that recent research has used to explain obesity disparities. Those nine mechanisms fall into three broad groups-health behaviors, biological factors, and the social environment-which incorporate both proximate and upstream determinants of obesity disparities. Efforts to reduce the prevalence of obesity in the US population and to close race/ethnic and SES disparities in obesity will likely require the use of multifaceted interventions that target multiple mechanisms simultaneously. Unfortunately, relatively few of the mechanisms reviewed herein have been tested in an intervention framework.

  8. Long release latencies are increased by acetylcholine at frog endplate

    Czech Academy of Sciences Publication Activity Database

    Samigullin, D.; Bukharaeva, E. A.; Nikolsky, E.; Adámek, S.; Vyskočil, František

    2003-01-01

    Roč. 52, č. 4 (2003), s. 475-480 ISSN 0862-8408 R&D Projects: GA ČR GA305/02/1333; GA ČR GA202/02/1213 Grant - others:RFBR(RU) 02/04/48901 Institutional research plan: CEZ:AV0Z5011922; CEZ:MSM 113100003 Keywords : quantal release * acetylcholine * synaptic latency Subject RIV: ED - Physiology Impact factor: 0.939, year: 2003

  9. Modulation of amplitude and latency of motor evoked potential by direction of transcranial magnetic stimulation

    Science.gov (United States)

    Sato, Aya; Torii, Tetsuya; Iwahashi, Masakuni; Itoh, Yuji; Iramina, Keiji

    2014-05-01

    The present study analyzed the effects of monophasic magnetic stimulation to the motor cortex. The effects of magnetic stimulation were evaluated by analyzing the motor evoked potentials (MEPs). The amplitude and latency of MEPs on the abductor pollicis brevis muscle were used to evaluate the effects of repetitive magnetic stimulation. A figure eight-shaped flat coil was used to stimulate the region over the primary motor cortex. The intensity of magnetic stimulation was 120% of the resting motor threshold, and the frequency of magnetic stimulation was 0.1 Hz. In addition, the direction of the current in the brain was posterior-anterior (PA) or anterior-posterior (AP). The latency of MEP was compared with PA and AP on initial magnetic stimulation. The results demonstrated that a stimulus in the AP direction increased the latency of the MEP by approximately 2.5 ms. MEP amplitude was also compared with PA and AP during 60 magnetic stimulations. The results showed that a stimulus in the PA direction gradually increased the amplitude of the MEP. However, a stimulus in the AP direction did not modulate the MEP amplitude. The average MEP amplitude induced from every 10 magnetic pulses was normalized by the average amplitude of the first 10 stimuli. These results demonstrated that the normalized MEP amplitude increased up to approximately 150%. In terms of pyramidal neuron indirect waves (I waves), magnetic stimulation inducing current flowing backward to the anterior preferentially elicited an I1 wave, and current flowing forward to the posterior elicited an I3 wave. It has been reported that the latency of the I3 wave is approximately 2.5 ms longer than the I1 wave elicitation, so the resulting difference in latency may be caused by this phenomenon. It has also been reported that there is no alteration of MEP amplitude at a frequency of 0.1 Hz. However, this study suggested that the modulation of MEP amplitude depends on stimulation strength and stimulation direction.

  10. Geographic disparity in kidney transplantation under KAS.

    Science.gov (United States)

    Zhou, Sheng; Massie, Allan B; Luo, Xun; Ruck, Jessica M; Chow, Eric K H; Bowring, Mary G; Bae, Sunjae; Segev, Dorry L; Gentry, Sommer E

    2017-12-12

    The Kidney Allocation System fundamentally altered kidney allocation, causing a substantial increase in regional and national sharing that we hypothesized might impact geographic disparities. We measured geographic disparity in deceased donor kidney transplant (DDKT) rate under KAS (6/1/2015-12/1/2016), and compared that with pre-KAS (6/1/2013-12/3/2014). We modeled DSA-level DDKT rates with multilevel Poisson regression, adjusting for allocation factors under KAS. Using the model we calculated a novel, improved metric of geographic disparity: the median incidence rate ratio (MIRR) of transplant rate, a measure of DSA-level variation that accounts for patient casemix and is robust to outlier values. Under KAS, MIRR was 1.75 1.81 1.86 for adults, meaning that similar candidates across different DSAs have a median 1.81-fold difference in DDKT rate. The impact of geography was greater than the impact of factors emphasized by KAS: having an EPTS score ≤20% was associated with a 1.40-fold increase (IRR =  1.35 1.40 1.45 , P geographic disparities with KAS (P = .3). Despite extensive changes to kidney allocation under KAS, geography remains a primary determinant of access to DDKT. © 2017 The American Society of Transplantation and the American Society of Transplant Surgeons.

  11. Determinants of health disparities between Italian regions

    Directory of Open Access Journals (Sweden)

    Giannoni Margherita

    2010-06-01

    Full Text Available Abstract Background Among European countries, Italy is one of the countries where regional health disparities contribute substantially to socioeconomic health disparities. In this paper, we report on regional differences in self-reported poor health and explore possible determinants at the individual and regional levels in Italy. Methods We use data from the "Indagine Multiscopo sulle Famiglie", a survey of aspects of everyday life in the Italian population, to estimate multilevel logistic regressions that model poor self-reported health as a function of individual and regional socioeconomic factors. Next we use the causal step approach to test if living conditions, healthcare characteristics, social isolation, and health behaviors at the regional level mediate the relationship between regional socioeconomic factors and self-rated health. Results We find that residents living in regions with more poverty, more unemployment, and more income inequality are more likely to report poor health and that poor living conditions and private share of healthcare expenditures at the regional level mediate socioeconomic disparities in self-rated health among Italian regions. Conclusion The implications are that regional contexts matter and that regional policies in Italy have the potential to reduce health disparities by implementing interventions aimed at improving living conditions and access to quality healthcare.

  12. Controlling disease and creating disparities: a fundamental cause perspective.

    Science.gov (United States)

    Phelan, Jo C; Link, Bruce G

    2005-10-01

    The United States and other developed countries experienced enormous improvements in population health during the 20th century. In the context of this dramatic positive change, health disparities by race and socioeconomic status emerged for several potent killers. Any explanation for current health disparities must take these changing patterns into account. Any explanation that ignores large improvements in population health and fails to account for the emergence of disparities for specific diseases is an inadequate explanation of current disparities. We argue that genetic explanations and some prominent social causation explanations are incompatible with these facts. We propose that the theory of "fundamental causes" can account for both vast improvements in population health and the creation of large socioeconomic and racial disparities in mortality for specific causes of death over time. Specifically, we argue that it is our enormously expanded capacity to control disease and death in combination with existing social and economic inequalities that create health disparities by race and socioeconomic status: When we develop the ability to control disease and death, the benefits of this new-found ability are distributed according to resources of knowledge, money, power, prestige, and beneficial social connections. We present data on changing mortality patterns by race and socioeconomic status for two types of diseases: those for which our capacity to prevent death has increased significantly and those for which we remain largely unable to prevent death. Time trends in mortality patterns are consistent with the fundamental cause explanation.

  13. Employment and Wage Disparities for Nurses With Activity Limitations.

    Science.gov (United States)

    Wilson, Barbara L; Butler, Richard J; Butler, Matthew J

    2016-11-01

    No studies quantify the labor market disparities between nurses with and without activity difficulties (physical impairment or disability). We explore disparate treatment of nurses with activity difficulties at three margins of the labor market: the ability to get a job, the relative wage rate offered once a nurse has a job, and the annual hours of work given that wage rate. Key variables from the American Community Survey (ACS) were analyzed, including basic demographic information, wages, hours of work, and employment status of registered nurses from 2006 to 2014. Although there is relatively little disparity in hourly wages, there is enormous disparity in the disabled's employment and hours of work opportunities, and hence a moderate amount of disparity in annual wages. This has significant implications for the nursing labor force, particularly as the nursing workforce continues to age and physical limitations or disabilities increase by 15-fold from 25 to 65 years of age.  Physical or psychological difficulties increase sharply over the course of a nurse's career, and employers must heighten efforts to facilitate an aging workforce and provide appropriate job accommodations for nurses with activity limitations. © 2016 Sigma Theta Tau International.

  14. Development tendencies of regional disparities in the Slovak Republic

    Directory of Open Access Journals (Sweden)

    Klamár Radoslav

    2016-01-01

    Full Text Available Presented paper deals with the issues of regional development and regional disparities in Slovakia in the years 2001-2014. Levelling respectively increase of regional disparities was evaluated through a set of 13 socio-economic indicators (gross birth rate, average monthly wage, monthly labour costs per employee, employment rate, unemployment rate, net monthly income and expenses per capita, completed dwellings, creation of GDP, labour productivity per employee in industry and construction, number of organizations focused on generating profit and number of freelancers which were used in the territorial units at the level of self-governing regions of the Slovak Republic (NUTS III level. In terms of the evaluation and comparison of regional disparities were used the Gini coefficient and the coefficient of variation for mutual comparison and validation of divergent or convergent tendencies of regional disparities in Slovakia.

  15. Aging and wave-component latency delays in oVEMP and cVEMP: a systematic review with meta-analysis.

    Science.gov (United States)

    Macambira, Ysa Karen Dos Santos; Carnaúba, Aline Tenório Lins; Fernandes, Luciana Castelo Branco Camurça; Bueno, Nassib Bezerra; Menezes, Pedro de Lemos

    The natural aging process may result in morphological changes in the vestibular system and in the afferent neural pathway, including loss of hair cells, decreased numbers of vestibular nerve cells, and loss of neurons in the vestibular nucleus. Thus, with advancing age, there should be a decrease in amplitudes and an increase in latencies of the vestibular evoked myogenic potentials, especially the prolongation of p13 latency. Moreover, many investigations have found no significant differences in latencies with advancing age. To determine if there are significant differences in the latencies of cervical and ocular evoked myogenic potentials between elderly and adult patients. This is a systematic review with meta-analysis of observational studies, comparing the differences of these parameters between elderly and young adults, without language or date restrictions, in the following databases: Pubmed, ScienceDirect, SCOPUS, Web of Science, SciELO and LILACS, in addition to the gray literature databases: OpenGrey.eu and DissOnline, as well as Research Gate. The n1 oVEMP latencies had a mean delay in the elderly of 2.32ms with 95% CI of 0.55-4.10ms. The overall effect test showed p=0.01, disclosing that such difference was significant. The heterogeneity found was I 2 =96% (p60 years than in young adults. Copyright © 2017 Associação Brasileira de Otorrinolaringologia e Cirurgia Cérvico-Facial. Published by Elsevier Editora Ltda. All rights reserved.

  16. From Motion to Photons in 80 Microseconds: Towards Minimal Latency for Virtual and Augmented Reality.

    Science.gov (United States)

    Lincoln, Peter; Blate, Alex; Singh, Montek; Whitted, Turner; State, Andrei; Lastra, Anselmo; Fuchs, Henry

    2016-04-01

    We describe an augmented reality, optical see-through display based on a DMD chip with an extremely fast (16 kHz) binary update rate. We combine the techniques of post-rendering 2-D offsets and just-in-time tracking updates with a novel modulation technique for turning binary pixels into perceived gray scale. These processing elements, implemented in an FPGA, are physically mounted along with the optical display elements in a head tracked rig through which users view synthetic imagery superimposed on their real environment. The combination of mechanical tracking at near-zero latency with reconfigurable display processing has given us a measured average of 80 µs of end-to-end latency (from head motion to change in photons from the display) and also a versatile test platform for extremely-low-latency display systems. We have used it to examine the trade-offs between image quality and cost (i.e. power and logical complexity) and have found that quality can be maintained with a fairly simple display modulation scheme.

  17. Hipster: hybrid task manager for latency-critical cloud workloads

    OpenAIRE

    Nishtala, Rajiv; Carpenter, Paul M.; Petrucci, Vinicius; Martorell Bofill, Xavier

    2017-01-01

    In 2013, U. S. data centers accounted for 2.2% of the country's total electricity consumption, a figure that is projected to increase rapidly over the next decade. Many important workloads are interactive, and they demand strict levels of quality-of-service (QoS) to meet user expectations, making it challenging to reduce power consumption due to increasing performance demands. This paper introduces Hipster, a technique that combines heuristics and reinforcement learning to manage latency-crit...

  18. Black-white preterm birth disparity: a marker of inequality

    Science.gov (United States)

    Purpose. The racial disparity in preterrn birth (PTB) is a persistent feature of perinatal epidemiology, inconsistently modeled in the literature. Rather than include race as an explanatory variable, or employ race-stratified models, we sought to directly model the PTB disparity ...

  19. An Investigation on the Role of Spike Latency in an Artificial Olfactory System

    Directory of Open Access Journals (Sweden)

    Corrado eDi Natale

    2011-12-01

    Full Text Available Experimental studies have shown that the reactions to external stimuli may appear only few hundreds of milliseconds after the physical interaction of the stimulus with the proper receptor. This behavior suggests that neurons transmit the largest meaningful part of their signal in the first spikes, and than that the spike latency is a good descriptor of the information content in biological neural networks. In this paper this property has been investigated in an artificial sensorial system where a single layer of spiking neurons is trained with the data generated by an artificial olfactory platform based on a large array of chemical sensors. The capability to discriminate between distinct chemicals and mixtures of them was studied with spiking neural networks endowed with and without lateral inhibitions and considering as output feature of the network both the spikes latency and the average firing rate. Results show that the average firing rate of the output spikes sequences shows the best separation among the experienced vapors, however the latency code is able in a shorter time to correctly discriminate all the tested volatile compounds. This behavior is qualitatively similar to those recently found in natural olfaction, and noteworthy it provides practical suggestions to tail the measurement conditions of artificial olfactory systems defining for each specific case a proper measurement time.

  20. Targeted HIV-1 Latency Reversal Using CRISPR/Cas9-Derived Transcriptional Activator Systems.

    Directory of Open Access Journals (Sweden)

    Julia K Bialek

    Full Text Available CRISPR/Cas9 technology is currently considered the most advanced tool for targeted genome engineering. Its sequence-dependent specificity has been explored for locus-directed transcriptional modulation. Such modulation, in particular transcriptional activation, has been proposed as key approach to overcome silencing of dormant HIV provirus in latently infected cellular reservoirs. Currently available agents for provirus activation, so-called latency reversing agents (LRAs, act indirectly through cellular pathways to induce viral transcription. However, their clinical performance remains suboptimal, possibly because reservoirs have diverse cellular identities and/or proviral DNA is intractable to the induced pathways. We have explored two CRISPR/Cas9-derived activator systems as targeted approaches to induce dormant HIV-1 proviral DNA. These systems recruit multiple transcriptional activation domains to the HIV 5' long terminal repeat (LTR, for which we have identified an optimal target region within the LTR U3 sequence. Using this target region, we demonstrate transcriptional activation of proviral genomes via the synergistic activation mediator complex in various in culture model systems for HIV latency. Observed levels of induction are comparable or indeed higher than treatment with established LRAs. Importantly, activation is complete, leading to production of infective viral particles. Our data demonstrate that CRISPR/Cas9-derived technologies can be applied to counteract HIV latency and may therefore represent promising novel approaches in the quest for HIV elimination.

  1. Effects of analog and digital filtering on auditory middle latency responses in adults and young children.

    Science.gov (United States)

    Suzuki, T; Hirabayashi, M; Kobayashi, K

    1984-01-01

    Effects of analog high pass (HP) filtering were compared with those of zero phase-shift digital filtering on the auditory middle latency responses (MLR) from nine adults and 16 young children with normal hearing. Analog HP filtering exerted several prominent effects on the MLR waveforms in both adults and young children, such as suppression of Po (ABR), enhancement of Nb, enhancement or emergence of Pb, and latency decrements for Pa and the later components. Analog HP filtering at 20 Hz produced more pronounced waveform distortions in the responses from young children than from adults. Much greater latency decrements for Pa and Nb were observed for young children than for adults in the analog HP-filtered responses at 20 Hz. A large positive peak (Pb) emerged at about 65 ms after the stimulus onset. From these results, the use of digital HP filtering at 20 Hz is strongly recommended for obtaining unbiased and stable MLR in young children.

  2. Flash Memory Reliability: Read, Program, and Erase Latency Versus Endurance Cycling

    Science.gov (United States)

    Heidecker, Jason

    2010-01-01

    This report documents the efforts and results of the fiscal year (FY) 2010 NASA Electronic Parts and Packaging Program (NEPP) task for nonvolatile memory (NVM) reliability. This year's focus was to measure latency (read, program, and erase) of NAND Flash memories and determine how these parameters drift with erase/program/read endurance cycling.

  3. Gender disparities in health care.

    Science.gov (United States)

    Kent, Jennifer A; Patel, Vinisha; Varela, Natalie A

    2012-01-01

    The existence of disparities in delivery of health care has been the subject of increased empirical study in recent years. Some studies have suggested that disparities between men and women exist in the diagnoses and treatment of health conditions, and as a result measures have been taken to identify these differences. This article uses several examples to illustrate health care gender bias in medicine. These examples include surgery, peripheral artery disease, cardiovascular disease, critical care, and cardiovascular risk factors. Additionally, we discuss reasons why these issues still occur, trends in health care that may address these issues, and the need for acknowledgement of the current system's inequities in order to provide unbiased care for women in the future. © 2012 Mount Sinai School of Medicine.

  4. Mind the Gap: Race\\Ethnic and Socioeconomic Disparities in Obesity

    OpenAIRE

    Krueger, Patrick M.; Reither, Eric N.

    2015-01-01

    Race/ethnic and socioeconomic status (SES) disparities in obesity are substantial and may widen in the future. We review seven potential mechanisms that recent research has used to explain obesity disparities. Those seven mechanisms fall into three broad groups—health behaviors, biological and developmental factors, and the social environment—which incorporate both proximate and upstream determinants of obesity disparities. Efforts to reduce the prevalence of obesity in the U.S. population an...

  5. Examining the Gap: Compensation Disparities between Male and Female Physician Assistants.

    Science.gov (United States)

    Smith, Noël; Cawley, James F; McCall, Timothy C

    Compensation disparities between men and women have been problematic for decades, and there is considerable evidence that the gap cannot be entirely explained by nongender factors. The current study examined the compensation gap in the physician assistant (PA) profession. Compensation data from 2014 was collected by the American Academy of PAs in 2015. Practice variables, including experience, specialty, and hours worked, were controlled for in an ordinary least-squares sequential regression model to examine whether there remained a disparity in total compensation. In addition, the absolute disparity in compensation was compared with historical data collected by American Academy of PAs over the previous 1.5 decades. Without controlling for practice variables, a total compensation disparity of $16,052 existed between men and women in the PA profession. Even after PA practice variables were controlled for, a total compensation disparity of $9,695 remained between men and women (95% confidence interval, $8,438-$10,952). A 17-year trend indicates the absolute disparity between men and women has not lessened, although the disparity as a percent of male compensation has decreased in recent years. There remain challenges to ensuring pay equality in the PA profession. Even when compensation-relevant factors such as experience, hours worked, specialty, postgraduate training, region, and call are controlled for, there is still a substantial gender disparity in PA compensation. Remedies that may address this pay inequality include raising awareness of compensation disparities, teaching effective negotiation skills, assisting employers as they develop equitable compensation plans, having less reliance on past salary in position negotiation, and professional associations advocating for policies that support equal wages and opportunities, regardless of personal characteristics. Copyright © 2017 Jacobs Institute of Women's Health. Published by Elsevier Inc. All rights reserved.

  6. Rate-distortion analysis of steganography for conveying stereovision disparity maps

    Science.gov (United States)

    Umeda, Toshiyuki; Batolomeu, Ana B. D. T.; Francob, Filipe A. L.; Delannay, Damien; Macq, Benoit M. M.

    2004-06-01

    3-D images transmission in a way which is compliant with traditional 2-D representations can be done through the embedding of disparity maps within the 2-D signal. This approach enables the transmission of stereoscopic video sequences or images on traditional analogue TV channels (PAL or NTSC) or printed photographic images. The aim of this work is to study the achievable performances of such a technique. The embedding of disparity maps has to be seen as a global rate-distortion problem. The embedding capacity through steganography is determined by the transmission channel noise and by the bearable distortion on the watermarked image. The distortion of the 3-D image displayed as two stereo views depends on the rate allocated to the complementary information required to build those two views from one reference 2-D image. Results from the works on the scalar Costa scheme are used to optimize the embedding of the disparity map compressed bit stream into the reference image. A method for computing the optimal trade off between the disparity map distortion and embedding distortion as a function of the channel impairments is proposed. The goal is to get a similar distortion on the left (the reference image) and the right (the disparity compensated image) images. We show that in typical situations the embedding of 2 bits/pixels in the left image, while the disparity map is compressed at 1 bit per pixel leads to a good trade-off. The disparity map is encoded with a strong error correcting code, including synchronisation bits.

  7. Partnering health disparities research with quality improvement science in pediatrics.

    Science.gov (United States)

    Lion, K Casey; Raphael, Jean L

    2015-02-01

    Disparities in pediatric health care quality are well described in the literature, yet practical approaches to decreasing them remain elusive. Quality improvement (QI) approaches are appealing for addressing disparities because they offer a set of strategies by which to target modifiable aspects of care delivery and a method for tailoring or changing an intervention over time based on data monitoring. However, few examples in the literature exist of QI interventions successfully decreasing disparities, particularly in pediatrics, due to well-described challenges in developing, implementing, and studying QI with vulnerable populations or in underresourced settings. In addition, QI interventions aimed at improving quality overall may not improve disparities, and in some cases, may worsen them if there is greater uptake or effectiveness of the intervention among the population with better outcomes at baseline. In this article, the authors review some of the challenges faced by researchers and frontline clinicians seeking to use QI to address health disparities and propose an agenda for moving the field forward. Specifically, they propose that those designing and implementing disparities-focused QI interventions reconsider comparator groups, use more rigorous evaluation methods, carefully consider the evidence for particular interventions and the context in which they were developed, directly engage the social determinants of health, and leverage community resources to build collaborative networks and engage community members. Ultimately, new partnerships between communities, providers serving vulnerable populations, and QI researchers will be required for QI interventions to achieve their potential related to health care disparity reduction. Copyright © 2015 by the American Academy of Pediatrics.

  8. Psychiatrists' attitudes toward and awareness about racial disparities in mental health care.

    Science.gov (United States)

    Mallinger, Julie B; Lamberti, J Steven

    2010-02-01

    Psychiatrists may perpetuate racial-ethnic disparities in health care through racially biased, albeit unconscious, behaviors. Changing these behaviors requires that physicians accept that racial-ethnic disparities exist and accept their own contributions to disparities. The purposes of this study were to assess psychiatrists' awareness of racial disparities in mental health care, to evaluate the extent to which psychiatrists believe they contribute to disparities, and to determine psychiatrists' interest in participating in disparities-reduction programs. A random sample of psychiatrists, identified through the American Psychiatric Association's member directory, was invited to complete the online survey. The survey was also distributed to psychiatrists at a national professional conference. Of the 374 respondents, most said they were not familiar or only a little familiar with the literature on racial disparities. Respondents tended to believe that race has a moderate influence on quality of psychiatric care but that race is more influential in others' practices than in their own practices. One-fourth had participated in any type of disparities-reduction program within the past year, and approximately one-half were interested in participating in such a program. Psychiatrists may not recognize the pervasiveness of racial inequality in psychiatric care, and they may attribute racially biased thinking to others but not to themselves. Interventions to eliminate racial-ethnic disparities should focus on revealing and modifying unconscious biases. Lack of physician interest may be one barrier to such interventions.

  9. Intranasal infection with Chlamydia abortus induces dose-dependent latency and abortion in sheep.

    Directory of Open Access Journals (Sweden)

    David Longbottom

    Full Text Available Latency is a key feature of the animal pathogen Chlamydia abortus, where infection remains inapparent in the non-pregnant animal and only becomes evident during a subsequent pregnancy. Often the first sign that an animal is infected is abortion occurring late in gestation. Despite this, little is understood of the underlying mechanisms that control latency or the recrudescence of infection that occurs during subsequent pregnancy. The aim of this study was to develop an experimental model of latency by mimicking the natural route of infection through the intranasal inoculation of non-pregnant sheep with C. abortus.Three groups of sheep (groups 1, 2 and 3 were experimentally infected with different doses of C. abortus (5×10(3, 5×10(5 and 5×10(7 inclusion forming units (IFU, respectively prior to mating and monitored over 2 breeding cycles for clinical, microbiological, pathological, immunological and serological outcomes. Two further groups received either negative control inoculum (group 4a,b or were inoculated subcutaneously on day 70 of gestation with 2×10(6 IFU C. abortus (group 5. Animals in groups 1, 2 and 5 experienced an abortion rate of 50-67%, while only one animal aborted in group 3 and none in group 4a,b. Pathological, microbiological, immunological and serological analyses support the view that the maternal protective immune response is influenced by initial exposure to the bacterium.The results show that intranasal administration of non-pregnant sheep with a low/medium dose of C. abortus results in a latent infection that leads in a subsequent pregnancy to infection of the placenta and abortion. In contrast a high dose stimulates protective immunity, resulting in a much lower abortion rate. This model will be useful in understanding the mechanisms of infection underlying latency and onset of disease, as well as in the development of novel therapeutics and vaccines for controlling infection.

  10. Intranasal infection with Chlamydia abortus induces dose-dependent latency and abortion in sheep.

    Science.gov (United States)

    Longbottom, David; Livingstone, Morag; Maley, Stephen; van der Zon, Arjan; Rocchi, Mara; Wilson, Kim; Wheelhouse, Nicholas; Dagleish, Mark; Aitchison, Kevin; Wattegedera, Sean; Nath, Mintu; Entrican, Gary; Buxton, David

    2013-01-01

    Latency is a key feature of the animal pathogen Chlamydia abortus, where infection remains inapparent in the non-pregnant animal and only becomes evident during a subsequent pregnancy. Often the first sign that an animal is infected is abortion occurring late in gestation. Despite this, little is understood of the underlying mechanisms that control latency or the recrudescence of infection that occurs during subsequent pregnancy. The aim of this study was to develop an experimental model of latency by mimicking the natural route of infection through the intranasal inoculation of non-pregnant sheep with C. abortus. Three groups of sheep (groups 1, 2 and 3) were experimentally infected with different doses of C. abortus (5×10(3), 5×10(5) and 5×10(7) inclusion forming units (IFU), respectively) prior to mating and monitored over 2 breeding cycles for clinical, microbiological, pathological, immunological and serological outcomes. Two further groups received either negative control inoculum (group 4a,b) or were inoculated subcutaneously on day 70 of gestation with 2×10(6) IFU C. abortus (group 5). Animals in groups 1, 2 and 5 experienced an abortion rate of 50-67%, while only one animal aborted in group 3 and none in group 4a,b. Pathological, microbiological, immunological and serological analyses support the view that the maternal protective immune response is influenced by initial exposure to the bacterium. The results show that intranasal administration of non-pregnant sheep with a low/medium dose of C. abortus results in a latent infection that leads in a subsequent pregnancy to infection of the placenta and abortion. In contrast a high dose stimulates protective immunity, resulting in a much lower abortion rate. This model will be useful in understanding the mechanisms of infection underlying latency and onset of disease, as well as in the development of novel therapeutics and vaccines for controlling infection.

  11. Area/latency optimized early output asynchronous full adders and relative-timed ripple carry adders.

    Science.gov (United States)

    Balasubramanian, P; Yamashita, S

    2016-01-01

    This article presents two area/latency optimized gate level asynchronous full adder designs which correspond to early output logic. The proposed full adders are constructed using the delay-insensitive dual-rail code and adhere to the four-phase return-to-zero handshaking. For an asynchronous ripple carry adder (RCA) constructed using the proposed early output full adders, the relative-timing assumption becomes necessary and the inherent advantages of the relative-timed RCA are: (1) computation with valid inputs, i.e., forward latency is data-dependent, and (2) computation with spacer inputs involves a bare minimum constant reverse latency of just one full adder delay, thus resulting in the optimal cycle time. With respect to different 32-bit RCA implementations, and in comparison with the optimized strong-indication, weak-indication, and early output full adder designs, one of the proposed early output full adders achieves respective reductions in latency by 67.8, 12.3 and 6.1 %, while the other proposed early output full adder achieves corresponding reductions in area by 32.6, 24.6 and 6.9 %, with practically no power penalty. Further, the proposed early output full adders based asynchronous RCAs enable minimum reductions in cycle time by 83.4, 15, and 8.8 % when considering carry-propagation over the entire RCA width of 32-bits, and maximum reductions in cycle time by 97.5, 27.4, and 22.4 % for the consideration of a typical carry chain length of 4 full adder stages, when compared to the least of the cycle time estimates of various strong-indication, weak-indication, and early output asynchronous RCAs of similar size. All the asynchronous full adders and RCAs were realized using standard cells in a semi-custom design fashion based on a 32/28 nm CMOS process technology.

  12. Race-Based Health Disparities and the Digital Divide: Implications for Nursing Practice.

    Science.gov (United States)

    Price, Zula

    2015-12-01

    Knowledge of the sources of race-based health disparities could improve nursing practice and education in minority underserved communities. This purpose of this paper was to consider if Black-nonBlack health disparities were at least in part explained by Black-nonBlack disparities in access to Internet-based health information. With data on the U.S. adult population from the 2012 General Social Survey, the parameters of a health production function in which computer usage as an input was estimated. It was found that while there are Black-nonBlack disparities in health, once computer usage was accounted for, Black-nonBlack health disparities disappeared. This suggests nursing and health interventions that improve Internet access for Black patients in underserved communities could improve the health of Black Americans and close the racial health disparities gap. These findings complement recent nursing researchfindings that suggest closing Black-nonBlack disparities in computer access, the "digital divide," can render nursing practice more effective in providing care to minority and underserved communities.

  13. Intracellular-activated Notch1 can reactivate Kaposi's sarcoma-associated herpesvirus from latency

    International Nuclear Information System (INIS)

    Lan, Ke; Murakami, Masanao; Choudhuri, Tathagata; Kuppers, Daniel A.; Robertson, Erle S.

    2006-01-01

    Kaposi's sarcoma-associated herpesvirus (KSHV) establishes a predominantly latent infection in the infected host. Importantly, during latency, only a small number of viral encoded genes are expressed. This viral gene expression pattern contributes to the establishment of long-term infection as well as the ability of the virus to evade the immune system. Previous studies have been shown that the replication and transcription activator (RTA) encoded by ORF50 activates it downstream genes and initiates viral lytic reactivation through functional interaction with RBP-Jκ, the major downstream effector of the Notch signaling pathway. This indicates that RTA can usurp the conserved Notch signaling pathway and mimic the activities of intracellular Notch1 to modulate gene expression. In this report, we show that the activated intracellular domain of Notch1 (ICN) is aberrantly accumulated in KSHV latently infected pleural effusion lymphoma (PEL) cells. ICN activated the RTA promoter in a dose-dependent manner, and forced expression of ICN in latently infected KSHV-positive cells initiated full blown lytic replication with the production of infectious viral progeny. However, latency-associated nuclear antigen (LANA) which is predominantly expressed during latency can specifically down-modulate ICN-mediated transactivation of RTA and so control KSHV for lytic reactivation. These results demonstrate that LANA can inhibit viral lytic replication by antagonizing ICN function and suggest that LANA is a critical component of the regulatory control mechanism for switching between viral latent and lytic replication by directly interacting with effectors of the conserved cellular Notch1 pathway

  14. Lossless Compression of Stereo Disparity Maps for 3D

    DEFF Research Database (Denmark)

    Zamarin, Marco; Forchhammer, Søren

    2012-01-01

    Efficient compression of disparity data is important for accurate view synthesis purposes in multi-view communication systems based on the “texture plus depth” format, including the stereo case. In this paper a novel technique for lossless compression of stereo disparity images is presented...

  15. Using temporal seeding to constrain the disparity search range in stereo matching

    CSIR Research Space (South Africa)

    Ndhlovu, T

    2011-11-01

    Full Text Available for reusing computed disparity estimates on features in a stereo image sequence to constrain the disparity search range. Features are detected on a left image and their disparity estimates are computed using a local-matching algorithm. The features...

  16. Foreword: Big Data and Its Application in Health Disparities Research.

    Science.gov (United States)

    Onukwugha, Eberechukwu; Duru, O Kenrik; Peprah, Emmanuel

    2017-01-01

    The articles presented in this special issue advance the conversation by describing the current efforts, findings and concerns related to Big Data and health disparities. They offer important recommendations and perspectives to consider when designing systems that can usefully leverage Big Data to reduce health disparities. We hope that ongoing Big Data efforts can build on these contributions to advance the conversation, address our embedded assumptions, and identify levers for action to reduce health care disparities.

  17. Reducing the PAPR in FBMC-OQAM systems with low-latency trellis-based SLM technique

    Science.gov (United States)

    Bulusu, S. S. Krishna Chaitanya; Shaiek, Hmaied; Roviras, Daniel

    2016-12-01

    Filter-bank multi-carrier (FBMC) modulations, and more specifically FBMC-offset quadrature amplitude modulation (OQAM), are seen as an interesting alternative to orthogonal frequency division multiplexing (OFDM) for the 5th generation radio access technology. In this paper, we investigate the problem of peak-to-average power ratio (PAPR) reduction for FBMC-OQAM signals. Recently, it has been shown that FBMC-OQAM with trellis-based selected mapping (TSLM) scheme not only is superior to any scheme based on symbol-by-symbol approach but also outperforms that of the OFDM with classical SLM scheme. This paper is an extension of that work, where we analyze the TSLM in terms of computational complexity, required hardware memory, and latency issues. We have proposed an improvement to the TSLM, which requires very less hardware memory, compared to the originally proposed TSLM, and also have low latency. Additionally, the impact of the time duration of partial PAPR on the performance of TSLM is studied, and its lower bound has been identified by proposing a suitable time duration. Also, a thorough and fair comparison of performance has been done with an existing trellis-based scheme proposed in literature. The simulation results show that the proposed low-latency TSLM yields better PAPR reduction performance with relatively less hardware memory requirements.

  18. Leading, but not trailing, primes influence temporal order perception: further evidence for an attentional account of perceptual latency priming.

    Science.gov (United States)

    Scharlau, Ingrid

    2002-11-01

    Presenting a masked prime leading a target influences the perceived onset of the masking target (perceptual latency priming; Scharlau & Neumann, in press). This priming effect is explained by the asynchronous updating model (Neumann, 1982; Scharlau & Neumann, in press): The prime initiates attentional allocation toward its location, which renders a trailing target at the same place consciously available earlier. In three experiments, this perceptual latency priming by leading primes was examined jointly with the effects of trailing primes in order to compare the explanation of the asynchronous updating model with the onset-averaging and the P-center hypotheses. Experiment 1 showed that an attended, as well as an unattended, prime leads to perceptual latency priming. In addition, a large effect of trailing primes on the onset of a target was found. As Experiment 2 demonstrated, this effect is quite robust, although smaller than that of a leading prime. In Experiment 3, masked primes were used. Under these conditions, no influence of trailing primes could be found, whereas perceptual latency priming persisted. Thus, a nonattentional explanation for the effect of trailing primes seems likely.

  19. Unequal before the Law : Measuring Legal Gender Disparities across the World

    OpenAIRE

    Iqbal, Sarah; Islam, Asif; Ramalho, Rita; Sakhonchik, Alena

    2016-01-01

    Several economies have laws that treat women differently from men. This study explores the degree of such legal gender disparities across 167 economies around the world. This is achieved by constructing a simple measure of legal gender disparities to evaluate how countries perform. The average number of overall legal gender disparities across 167 economies is 17, ranging from a minimum of ...

  20. Racial/ethnic disparity in obesity among US youth, 1999-2013.

    Science.gov (United States)

    An, Ruopeng

    2015-11-04

    One fundamental goal in the Healthy People 2020 is to achieve health equity and eliminate disparities. To examine the annual trends in racial/ethnic disparity in obesity among US youth from 1999 to 2013. Nationally representative sample of 108,811 students in grades 9th-12th from the Youth Risk Behavior Surveillance System (YRBSS) 1999-2013 surveys. Body mass index (BMI) was calculated based on self-reported height and weight. Obesity in youth is defined as BMI at or above 95th sex- and age-specific percentile of the 2000 Centers for Disease Control and Prevention growth charts. Multiple logistic regressions were conducted to estimate the annual prevalence of obesity by race/ethnicity, adjusted for gender and age group and accounted for the YRBSS survey design. Between-group variance (BGV) was used to measure absolute racial/ethnic disparity in obesity, and the mean log deviation (MLD) and the Theil Index (T) were used to measure relative racial/ethnic disparity in obesity, weighted by corresponding racial/ethnic population size. The obesity prevalence among non-Hispanic Whites, non-Hispanic African Americans, non-Hispanic other race or multi-race, and Hispanic increased from 10.05%, 12.31%, 10.25%, and 13.24% in 1999 to 13.14%, 15.76%, 10.87%, and 15.20% in 2013, respectively. Both absolute and relative racial/ethnic disparity in obesity increased initially since 1999 but then steadily declined starting from mid-2000s back to around its original level by 2013. The obesity epidemic in youth is marked by salient and persistent disparity pertaining to race/ethnicity. No improvement on racial/ethnic disparity in obesity among American youth was observed during 1999-2013.

  1. Auditory brainstem response latency in forward masking, a marker of sensory deficits in listeners with normal hearing thresholds

    DEFF Research Database (Denmark)

    Mehraei, Golbarg; Paredes Gallardo, Andreu; Shinn-Cunningham, Barbara G.

    2017-01-01

    In rodent models, acoustic exposure too modest to elevate hearing thresholds can nonetheless cause auditory nerve fiber deafferentation, interfering with the coding of supra-threshold sound. Low-spontaneous rate nerve fibers, important for encoding acoustic information at supra-threshold levels...... and in noise, are more susceptible to degeneration than high-spontaneous rate fibers. The change in auditory brainstem response (ABR) wave-V latency with noise level has been shown to be associated with auditory nerve deafferentation. Here, we measured ABR in a forward masking paradigm and evaluated wave......-V latency changes with increasing masker-to-probe intervals. In the same listeners, behavioral forward masking detection thresholds were measured. We hypothesized that 1) auditory nerve fiber deafferentation increases forward masking thresholds and increases wave-V latency and 2) a preferential loss of low...

  2. Male/Female Salary Disparity for Professors of Educational Administration.

    Science.gov (United States)

    Pounder, Diana G.

    The earnings gap between male and female workers across all occupational groups has been well documented; full-time women workers earn, on average, approximately 65 percent of men's salaries. Although male/female salary disparity is largest across occupational groups, salary disparity within occupational groups still prevails. For example, the…

  3. Objective quality assessment of stereoscopic images with vertical disparity using EEG

    Science.gov (United States)

    Shahbazi Avarvand, Forooz; Bosse, Sebastian; Müller, Klaus-Robert; Schäfer, Ralf; Nolte, Guido; Wiegand, Thomas; Curio, Gabriel; Samek, Wojciech

    2017-08-01

    Objective. Neurophysiological correlates of vertical disparity in 3D images are studied in an objective approach using EEG technique. These disparities are known to negatively affect the quality of experience and to cause visual discomfort in stereoscopic visualizations. Approach. We have presented four conditions to subjects: one in 2D and three conditions in 3D, one without vertical disparity and two with different vertical disparity levels. Event related potentials (ERPs) are measured for each condition and the differences between ERP components are studied. Analysis is also performed on the induced potentials in the time frequency domain. Main results. Results show that there is a significant increase in the amplitude of P1 components in 3D conditions in comparison to 2D. These results are consistent with previous studies which have shown that P1 amplitude increases due to the depth perception in 3D compared to 2D. However the amplitude is significantly smaller for maximum vertical disparity (3D-3) in comparison to 3D with no vertical disparity. Our results therefore suggest that the vertical disparity in 3D-3 condition decreases the perception of depth compared to other 3D conditions and the amplitude of P1 component can be used as a discriminative feature. Significance. The results show that the P1 component increases in amplitude due to the depth perception in the 3D stimuli compared to the 2D stimulus. On the other hand the vertical disparity in the stereoscopic images is studied here. We suggest that the amplitude of P1 component is modulated with this parameter and decreases due to the decrease in the perception of depth.

  4. 75 FR 29357 - National Center on Minority and Health Disparities; Notice of Closed Meeting

    Science.gov (United States)

    2010-05-25

    ... and Health Disparities; Notice of Closed Meeting Pursuant to section 10(d) of the Federal Advisory... and Health Disparities Special NCMHD Health Disparities Research on Minority and Underserved... Health and Health Disparities, 6707 Democracy Boulevard, Suite 800, Bethesda, MD 20892. (301) 594-8696...

  5. The amblyopic eye in subjects with anisometropia show increased saccadic latency in the delayed saccade task

    Directory of Open Access Journals (Sweden)

    Maciej ePerdziak

    2014-10-01

    Full Text Available The term amblyopia is used to describe reduced visual function in one eye (or both eyes, though not so often which cannot be fully improved by refractive correction and explained by the organic cause observed during regular eye examination. This developmental disorder of spatial vision affects about 2-5% of the population and is associated with abnormal visual experience (e.g. anisometropia, strabismus during infancy or early childhood. Several studies have shown prolongation of saccadic latency time in amblyopic eye. In our opinion, study of saccadic latency in the context of central vision deficits assessment, should be based on central retina stimulation. For this reason, we proposed saccade delayed task. It requires inhibitory processing for maintaining fixation on the central target until it disappears – what constitutes the GO signal for saccade. The experiment consisted of 100 trials for each eye and was performed under two viewing conditions: monocular amblyopic / non-dominant eye and monocular dominant eye. We examined saccadic latency in 16 subjects (mean age 30±11 years with anisometropic amblyopia (two subjects had also microtropia and in 17 control subjects (mean age 28±8 years. Participants were instructed to look at central (fixation target and when it disappears, to make the saccade toward the periphery (10 deg as fast as possible, either left or the right target. The study results have proved the significant difference in saccadic latency between the amblyopic (mean 262±48 ms and dominant (mean 237±45 ms eye, in anisometropic group. In the control group, the saccadic latency for dominant (mean 226±32ms and non-dominant (mean 230±29 ms eye was not significantly different.By the use of LATER (Linear Approach to the Threshold with Ergodic Rate decision model we interpret our findings as a decrease in accumulation of visual information acquired by means of central (affected retina in subjects with anisometropic amblyopia.

  6. Human Space Exploration and Human Space Flight: Latency and the Cognitive Scale of the Universe

    Science.gov (United States)

    Lester, Dan; Thronson, Harley

    2011-01-01

    The role of telerobotics in space exploration as placing human cognition on other worlds is limited almost entirely by the speed of light, and the consequent communications latency that results from large distances. This latency is the time delay between the human brain at one end, and the telerobotic effector and sensor at the other end. While telerobotics and virtual presence is a technology that is rapidly becoming more sophisticated, with strong commercial interest on the Earth, this time delay, along with the neurological timescale of a human being, quantitatively defines the cognitive horizon for any locale in space. That is, how distant can an operator be from a robot and not be significantly impacted by latency? We explore that cognitive timescale of the universe, and consider the implications for telerobotics, human space flight, and participation by larger numbers of people in space exploration. We conclude that, with advanced telepresence, sophisticated robots could be operated with high cognition throughout a lunar hemisphere by astronauts within a station at an Earth-Moon Ll or L2 venue. Likewise, complex telerobotic servicing of satellites in geosynchronous orbit can be carried out from suitable terrestrial stations.

  7. The Health Effects of Income Inequality: Averages and Disparities.

    Science.gov (United States)

    Truesdale, Beth C; Jencks, Christopher

    2016-01-01

    Much research has investigated the association of income inequality with average life expectancy, usually finding negative correlations that are not very robust. A smaller body of work has investigated socioeconomic disparities in life expectancy, which have widened in many countries since 1980. These two lines of work should be seen as complementary because changes in average life expectancy are unlikely to affect all socioeconomic groups equally. Although most theories imply long and variable lags between changes in income inequality and changes in health, empirical evidence is confined largely to short-term effects. Rising income inequality can affect individuals in two ways. Direct effects change individuals' own income. Indirect effects change other people's income, which can then change a society's politics, customs, and ideals, altering the behavior even of those whose own income remains unchanged. Indirect effects can thus change both average health and the slope of the relationship between individual income and health.

  8. JPEG XS, a new standard for visually lossless low-latency lightweight image compression

    Science.gov (United States)

    Descampe, Antonin; Keinert, Joachim; Richter, Thomas; Fößel, Siegfried; Rouvroy, Gaël.

    2017-09-01

    JPEG XS is an upcoming standard from the JPEG Committee (formally known as ISO/IEC SC29 WG1). It aims to provide an interoperable visually lossless low-latency lightweight codec for a wide range of applications including mezzanine compression in broadcast and Pro-AV markets. This requires optimal support of a wide range of implementation technologies such as FPGAs, CPUs and GPUs. Targeted use cases are professional video links, IP transport, Ethernet transport, real-time video storage, video memory buffers, and omnidirectional video capture and rendering. In addition to the evaluation of the visual transparency of the selected technologies, a detailed analysis of the hardware and software complexity as well as the latency has been done to make sure that the new codec meets the requirements of the above-mentioned use cases. In particular, the end-to-end latency has been constrained to a maximum of 32 lines. Concerning the hardware complexity, neither encoder nor decoder should require more than 50% of an FPGA similar to Xilinx Artix 7 or 25% of an FPGA similar to Altera Cyclon 5. This process resulted in a coding scheme made of an optional color transform, a wavelet transform, the entropy coding of the highest magnitude level of groups of coefficients, and the raw inclusion of the truncated wavelet coefficients. This paper presents the details and status of the standardization process, a technical description of the future standard, and the latest performance evaluation results.

  9. 76 FR 63310 - National Center On Minority and Health Disparities Notice of Closed Meetings

    Science.gov (United States)

    2011-10-12

    ... and Health Disparities Notice of Closed Meetings Pursuant to section 10(d) of the Federal Advisory... and Health Disparities Special Emphasis Panel; NIMHD Health Disparities Research (R01). Date: November... Disparities, National Institutes of Health, 6707 Democracy Blvd., MSC. 5465, Suite 800, Bethesda, MD 20892...

  10. Downlink Transmission of Short Packets

    DEFF Research Database (Denmark)

    Trillingsgaard, Kasper Fløe; Popovski, Petar

    2017-01-01

    Cellular wireless systems rely on frame-based transmissions. The frame design is conventionally based on heuristics, consisting of a frame header and a data part. The frame header contains control information that provides pointers to the messages within the data part. In this paper, we revisit...... the principles of frame design and show the impact of the new design in scenarios that feature short data packets, which are central to various 5G and Internet of Things applications. We~treat framing for downlink transmission in an AWGN broadcast channel with $K$ users, where the sizes of the messages....... This requires changes in the way control information is sent, and it requires that the users need to spend power decoding other messages, thereby increasing the average power consumption. We~show that the common heuristic design is only one point on a curve that represents the tradeoff between latency and power...

  11. Disparities in abortion experience and access to safe abortion ...

    African Journals Online (AJOL)

    In Ghana, abortion mortality constitutes 11% of maternal mortality. Empirical studies on possible disparities in abortion experience and access to safe abortion services are however lacking. Based on a retrospective survey of 1,370 women aged 15-49 years in two districts in Ghana, this paper examines disparities in ...

  12. Localization of latency-associated nuclear antigen (LANA) on mitotic chromosomes

    Energy Technology Data Exchange (ETDEWEB)

    Rahayu, Retno; Ohsaki, Eriko [Division of Virology, Department of Microbiology and Immunology, Osaka University Graduate School of Medicine, 2-2 Yamada-oka, Suita, Osaka 565-0871 (Japan); Omori, Hiroko [Central Instrumentation Laboratory Research Institute for Microbial Diseases (BIKEN), Osaka University, Osaka 565-0871 (Japan); Ueda, Keiji, E-mail: kueda@virus.med.osaka-u.ac.jp [Division of Virology, Department of Microbiology and Immunology, Osaka University Graduate School of Medicine, 2-2 Yamada-oka, Suita, Osaka 565-0871 (Japan)

    2016-09-15

    In latent infection of Kaposi's sarcoma-associated herpesvirus (KSHV), viral gene expression is extremely limited and copy numbers of viral genomes remain constant. Latency-associated nuclear antigen (LANA) is known to have a role in maintaining viral genome copy numbers in growing cells. Several studies have shown that LANA is localized in particular regions on mitotic chromosomes, such as centromeres/pericentromeres. We independently examined the distinct localization of LANA on mitotic chromosomes during mitosis, using super-resolution laser confocal microscopy and correlative fluorescence microscopy–electron microscopy (FM-EM) analyses. We found that the majority of LANA were not localized at particular regions such as telomeres/peritelomeres, centromeres/pericentromeres, and cohesion sites, but at the bodies of condensed chromosomes. Thus, LANA may undergo various interactions with the host factors on the condensed chromosomes in order to tether the viral genome to mitotic chromosomes and realize faithful viral genome segregation during cell division. - Highlights: • This is the first report showing LANA dots on mitotic chromosomes by fluorescent microscopy followed by electron microscopy. • LANA dots localized randomly on condensed chromosomes other than centromere/pericentromere and telomere/peritelomre. • Cellular mitotic checkpoint should not be always involved in the segregation of KSHV genomes in the latency.

  13. Localization of latency-associated nuclear antigen (LANA) on mitotic chromosomes

    International Nuclear Information System (INIS)

    Rahayu, Retno; Ohsaki, Eriko; Omori, Hiroko; Ueda, Keiji

    2016-01-01

    In latent infection of Kaposi's sarcoma-associated herpesvirus (KSHV), viral gene expression is extremely limited and copy numbers of viral genomes remain constant. Latency-associated nuclear antigen (LANA) is known to have a role in maintaining viral genome copy numbers in growing cells. Several studies have shown that LANA is localized in particular regions on mitotic chromosomes, such as centromeres/pericentromeres. We independently examined the distinct localization of LANA on mitotic chromosomes during mitosis, using super-resolution laser confocal microscopy and correlative fluorescence microscopy–electron microscopy (FM-EM) analyses. We found that the majority of LANA were not localized at particular regions such as telomeres/peritelomeres, centromeres/pericentromeres, and cohesion sites, but at the bodies of condensed chromosomes. Thus, LANA may undergo various interactions with the host factors on the condensed chromosomes in order to tether the viral genome to mitotic chromosomes and realize faithful viral genome segregation during cell division. - Highlights: • This is the first report showing LANA dots on mitotic chromosomes by fluorescent microscopy followed by electron microscopy. • LANA dots localized randomly on condensed chromosomes other than centromere/pericentromere and telomere/peritelomre. • Cellular mitotic checkpoint should not be always involved in the segregation of KSHV genomes in the latency.

  14. Examples of Cancer Health Disparities

    Science.gov (United States)

    ... and the bacterium H. pylori (stomach cancer) in immigrant countries of origin contributes to these disparities. ( ACS ) ... Cancer.gov en español Multimedia Publications Site Map Digital Standards for NCI Websites POLICIES Accessibility Comment Policy ...

  15. Socio-economic disparities in health system responsiveness in India.

    Science.gov (United States)

    Malhotra, Chetna; Do, Young Kyung

    2013-03-01

    To assess the magnitude of socio-economic disparities in health system responsiveness in India after correcting for potential reporting heterogeneity by socio-economic characteristics (education and wealth). Data from Wave 1 of the Study on Global Ageing and Adult Health (2007-2008) involving six Indian states were used. Seven health system responsiveness domains were considered for a respondent's last visit to an outpatient service in 12 months: prompt attention, dignity, clarity of information, autonomy, confidentiality, choice and quality of basic amenities. Hierarchical ordered probit models (correcting for reporting heterogeneity through anchoring vignettes) were used to assess the association of socio-economic characteristics with the seven responsiveness domains, controlling for age, gender and area of residence. Stratified analysis was also conducted among users of public and private health facilities. Our statistical models accounting for reporting heterogeneity revealed socio-economic disparities in all health system responsiveness domains. Estimates suggested that individuals from the lowest wealth group, for example, were less likely than individuals from the highest wealth group to report 'very good' on the dignity domain by 8% points (10% vs 18%). Stratified analysis showed that such disparities existed among users of both public and private health facilities. Socio-economic disparities exist in health system responsiveness in India, irrespective of the type of health facility used. Policy efforts to monitor and improve these disparities are required at the health system level.

  16. An Ultra-Low-Latency Geo-Routing Scheme for Team-Based Unmanned Vehicular Applications

    KAUST Repository

    Bader, Ahmed; Alouini, Mohamed-Slim

    2016-01-01

    Results and lessons learned from the implementation of a novel ultra low-latency geo-routing scheme are presented in this paper. The geo-routing scheme is intended for team-based mobile systems whereby a cluster of unmanned autonomous vehicles

  17. Racial and ethnic disparities in U.S. cancer screening rates

    Science.gov (United States)

    The percentage of U.S. citizens screened for cancer remains below national targets, with significant disparities among racial and ethnic populations, according to the first federal study to identify cancer screening disparities among Asian and Hispanic gr

  18. January Monthly Spotlight: Cervical Health and Cervical Cancer Disparities

    Science.gov (United States)

    In January, CRCHD joins the nation in raising awareness for Cervical Health and Cervical Cancer Disparities. This month we share a special focus on NCI/CRCHD research programs that are trying to reduce cervical cancer disparities in underserved communities and the people who are spreading the word about the importance of early detection.

  19. Anticipation of direction and time of perturbation modulates the onset latency of trunk muscle responses during sitting perturbations.

    Science.gov (United States)

    Milosevic, Matija; Shinya, Masahiro; Masani, Kei; Patel, Kramay; McConville, Kristiina M V; Nakazawa, Kimitaka; Popovic, Milos R

    2016-02-01

    Trunk muscles are responsible for maintaining trunk stability during sitting. However, the effects of anticipation of perturbation on trunk muscle responses are not well understood. The objectives of this study were to identify the responses of trunk muscles to sudden support surface translations and quantify the effects of anticipation of direction and time of perturbation on the trunk neuromuscular responses. Twelve able-bodied individuals participated in the study. Participants were seated on a kneeling chair and support surface translations were applied in the forward and backward directions with and without direction and time of perturbation cues. The trunk started moving on average approximately 40ms after the perturbation. During unanticipated perturbations, average latencies of the trunk muscle contractions were in the range between 103.4 and 117.4ms. When participants anticipated the perturbations, trunk muscle latencies were reduced by 16.8±10.0ms and the time it took the trunk to reach maximum velocity was also reduced, suggesting a biomechanical advantage caused by faster muscle responses. These results suggested that trunk muscles have medium latency responses and use reflexive mechanisms. Moreover, anticipation of perturbation decreased trunk muscles latencies, suggesting that the central nervous system modulated readiness of the trunk based on anticipatory information. Copyright © 2015 Elsevier Ltd. All rights reserved.

  20. Low-power low-latency MAC protocol for aeronautical applications

    Science.gov (United States)

    Sabater, Jordi; Kluge, Martin; Bovelli, Sergio; Schalk, Josef

    2007-05-01

    This paper describes asynchronous MAC (Medium Access Control) strategies based on the IEEE 802.15.4 physical layer for wireless aeronautical applications where low power and low latency are important requirements as well as security and data integrity. Sensor data is acquired and collected on request, by means of a mobile device, and later stored in a centralized database. In order to have the smallest power consumption the wireless sensor has to remain in deep sleep mode as long as possible and wake up and listen periodically for RF activity. If its unique ID is mentioned in the destination address field, the complete frame is received, processed and replied if necessary. If the detected packet is addressed to another sensor the reception will stop immediately and the wireless sensor will go into deep sleep mode again. Listening instead of sending actively does not 'pollute' the already crowded 2.45GHz spectrum, reduces collisions and increases security. The mobile data concentrator can not be synchronized with all the sensors installed in a distributed environment, therefore smart asynchronous data transmission strategies are needed to reduce latencies and increase throughput. For the considered application, sensors are independent of each other, simply share the medium and together with the data concentrator are organized in a star network topology. The centre of the star is the concentrator which is rarely in range. It coordinates and activates the wireless sensor nodes to collect the measured data.

  1. Revisiting the Latency of Uridine Diphosphate-Glucuronosyltransferases (UGTs—How Does the Endoplasmic Reticulum Membrane Influence Their Function?

    Directory of Open Access Journals (Sweden)

    Yuejian Liu

    2017-08-01

    Full Text Available Uridine diphosphate-glucuronosyltransferases (UGTs are phase 2 conjugation enzymes mainly located in the endoplasmic reticulum (ER of the liver and many other tissues, and can be recovered in artificial ER membrane preparations (microsomes. They catalyze glucuronidation reactions in various aglycone substrates, contributing significantly to the body’s chemical defense mechanism. There has been controversy over the last 50 years in the UGT field with respect to the explanation for the phenomenon of latency: full UGT activity revealed by chemical or physical disruption of the microsomal membrane. Because latency can lead to inaccurate measurements of UGT activity in vitro, and subsequent underprediction of drug clearance in vivo, it is important to understand the mechanisms behind this phenomenon. Three major hypotheses have been advanced to explain UGT latency: compartmentation, conformation, and adenine nucleotide inhibition. In this review, we discuss the evidence behind each hypothesis in depth, and suggest some additional studies that may reveal more information on this intriguing phenomenon.

  2. The Effects of Hurricane Katrina on Food Access Disparities in New Orleans

    Science.gov (United States)

    Bodor, J. Nicholas; Rice, Janet C.; Swalm, Chris M.; Hutchinson, Paul L.

    2011-01-01

    Disparities in neighborhood food access are well documented, but little research exists on how shocks influence such disparities. We examined neighborhood food access in New Orleans at 3 time points: before Hurricane Katrina (2004–2005), in 2007, and in 2009. We combined existing directories with on-the-ground verification and geographic information system mapping to assess supermarket counts in the entire city. Existing disparities for African American neighborhoods worsened after the storm. Although improvements have been made, by 2009 disparities were no better than prestorm levels. PMID:21233432

  3. Effect of Medicaid Managed Care on racial disparities in health care access.

    Science.gov (United States)

    Cook, Benjamin Lê

    2007-02-01

    To evaluate the impact of Medicaid Managed Care (MMC) on racial disparities in access to care consistent with the Institute of Medicine (IOM) definition of racial disparity, which excludes differences stemming from health status but includes socioeconomic status (SES)-mediated differences. Secondary data from the Adult Samples of the 1997-2001 National Health Interview Survey, metropolitan statistical area (MSA)-level Medicaid Health Maintenance Organization (MHMO) market share from the 1997 to 2001 InterStudy MSA Trend Dataset, and MSA characteristics from the 1997 to 2001 Area Resource File. I estimate multivariate regression models to compare racial disparities in doctor visits, emergency room (ER) use, and having a usual source of care between enrollees in MMC and Medicaid Fee-for-Service (FFS) plans. To contend with potential selection bias, I use a difference-in-difference analytical strategy and assess the impact of greater MHMO market share at the MSA level on Medicaid enrollees' access measures. To implement the IOM definition of racial disparity, I adjust for health status but not SES factors using a novel method to transform the distribution of health status for minority populations to approximate the white health status distribution. MMC enrollment is associated with lowered disparities in having any doctor visit in the last year for blacks, and in having any usual source of care for both blacks and Hispanics. Increasing Medicaid HMO market share lowered disparities in having any doctor visits in the last year for both blacks and Hispanics. Although disparities in most other measures were not much affected, black-white ER use disparities exist among MMC enrollees and in areas of high MHMO market share. MMC programs' reduction of some disparities suggests that recent shifts in Medicaid policy toward managed care plans have benefited minority enrollees. Future research should investigate whether black-white disparities in ER use within MMC groups

  4. HTMT-class Latency Tolerant Parallel Architecture for Petaflops Scale Computation

    Science.gov (United States)

    Sterling, Thomas; Bergman, Larry

    2000-01-01

    semiconductor logic. Wave Division Multiplexing optical communications can approach a peak per fiber bandwidth of 1 Tbps and the new Data Vortex network topology employing this technology can connect tens of thousands of ports providing a bi-section bandwidth on the order of a Petabyte per second with latencies well below 100 nanoseconds, even under heavy loads. Processor-in-Memory (PIM) technology combines logic and memory on the same chip exposing the internal bandwidth of the memory row buffers at low latency. And holographic storage photorefractive storage technologies provide high-density memory with access a thousand times faster than conventional disk technologies. Together these technologies enable a new class of shared memory system architecture with a peak performance in the range of a Petaflops but size and power requirements comparable to today's largest Teraflops scale systems. To achieve high-sustained performance, HTMT combines an advanced multithreading processor architecture with a memory-driven coarse-grained latency management strategy called "percolation", yielding high efficiency while reducing the much of the parallel programming burden. This paper will present the basic system architecture characteristics made possible through this series of advanced technologies and then give a detailed description of the new percolation approach to runtime latency management.

  5. Detailed analysis of latencies in image-based dynamic MLC tracking

    International Nuclear Information System (INIS)

    Poulsen, Per Rugaard; Cho, Byungchul; Sawant, Amit; Ruan, Dan; Keall, Paul J.

    2010-01-01

    Purpose: Previous measurements of the accuracy of image-based real-time dynamic multileaf collimator (DMLC) tracking show that the major contributor to errors is latency, i.e., the delay between target motion and MLC response. Therefore the purpose of this work was to develop a method for detailed analysis of latency contributions during image-based DMLC tracking. Methods: A prototype DMLC tracking system integrated with a linear accelerator was used for tracking a phantom with an embedded fiducial marker during treatment delivery. The phantom performed a sinusoidal motion. Real-time target localization was based on x-ray images acquired either with a portal imager or a kV imager mounted orthogonal to the treatment beam. Each image was stored in a file on the imaging workstation. A marker segmentation program opened the image file, determined the marker position in the image, and transferred it to the DMLC tracking program. This program estimated the three-dimensional target position by a single-imager method and adjusted the MLC aperture to the target position. Imaging intervals ΔT image from 150 to 1000 ms were investigated for both kV and MV imaging. After the experiments, the recorded images were synchronized with MLC log files generated by the MLC controller and tracking log files generated by the tracking program. This synchronization allowed temporal analysis of the information flow for each individual image from acquisition to completed MLC adjustment. The synchronization also allowed investigation of the MLC adjustment dynamics on a considerably finer time scale than the 50 ms time resolution of the MLC log files. Results: For ΔT image =150 ms, the total time from image acquisition to completed MLC adjustment was 380±9 ms for MV and 420±12 ms for kV images. The main part of this time was from image acquisition to completed image file writing (272 ms for MV and 309 ms for kV). Image file opening (38 ms), marker segmentation (4 ms), MLC position

  6. Detailed analysis of latencies in image-based dynamic MLC tracking

    Energy Technology Data Exchange (ETDEWEB)

    Poulsen, Per Rugaard; Cho, Byungchul; Sawant, Amit; Ruan, Dan; Keall, Paul J. [Department of Radiation Oncology, Stanford University, Stanford, California 94305 and Department of Oncology and Department of Medical Physics, Aarhus University Hospital, 8000 Aarhus (Denmark); Department of Radiation Oncology, Stanford University, Stanford, California 94305 and Department of Radiation Oncology, Asan Medical Center, Seoul 138-736 (Korea, Republic of); Department of Radiation Oncology, Stanford University, Stanford, California 94305 (United States)

    2010-09-15

    Purpose: Previous measurements of the accuracy of image-based real-time dynamic multileaf collimator (DMLC) tracking show that the major contributor to errors is latency, i.e., the delay between target motion and MLC response. Therefore the purpose of this work was to develop a method for detailed analysis of latency contributions during image-based DMLC tracking. Methods: A prototype DMLC tracking system integrated with a linear accelerator was used for tracking a phantom with an embedded fiducial marker during treatment delivery. The phantom performed a sinusoidal motion. Real-time target localization was based on x-ray images acquired either with a portal imager or a kV imager mounted orthogonal to the treatment beam. Each image was stored in a file on the imaging workstation. A marker segmentation program opened the image file, determined the marker position in the image, and transferred it to the DMLC tracking program. This program estimated the three-dimensional target position by a single-imager method and adjusted the MLC aperture to the target position. Imaging intervals {Delta}T{sub image} from 150 to 1000 ms were investigated for both kV and MV imaging. After the experiments, the recorded images were synchronized with MLC log files generated by the MLC controller and tracking log files generated by the tracking program. This synchronization allowed temporal analysis of the information flow for each individual image from acquisition to completed MLC adjustment. The synchronization also allowed investigation of the MLC adjustment dynamics on a considerably finer time scale than the 50 ms time resolution of the MLC log files. Results: For {Delta}T{sub image}=150 ms, the total time from image acquisition to completed MLC adjustment was 380{+-}9 ms for MV and 420{+-}12 ms for kV images. The main part of this time was from image acquisition to completed image file writing (272 ms for MV and 309 ms for kV). Image file opening (38 ms), marker segmentation (4 ms

  7. Temporal suppression of long-latency click-evoked otoacoustic emissions

    DEFF Research Database (Denmark)

    Verhulst, Sarah; Harte, James; Dau, Torsten

    2007-01-01

    A comprehensive set of results from double click suppression experiments on otoacoustic emissions (OAEs) have been presented by Hine and Thornton (2002) and Kapadia and Lutman (2000). They found that suppression of a click-evoked otoacoustic emission (CEOAE) varied with the timing and level...... subjects showed that the nonlinear suppression effect remained on the long-latency CEOAE, indicating that both SOAEs and CEOAEs originate from the same cochlear nonlinearities, as earlier suggested by Kemp and Chum (1980). The apparent similar origin of both types of emissions implies that the same...

  8. Prioritizing health disparities in medical education to improve care

    Science.gov (United States)

    Awosogba, Temitope; Betancourt, Joseph R.; Conyers, F. Garrett; Estapé, Estela S.; Francois, Fritz; Gard, Sabrina J.; Kaufman, Arthur; Lunn, Mitchell R.; Nivet, Marc A.; Oppenheim, Joel D.; Pomeroy, Claire; Yeung, Howa

    2015-01-01

    Despite yearly advances in life-saving and preventive medicine, as well as strategic approaches by governmental and social agencies and groups, significant disparities remain in health, health quality, and access to health care within the United States. The determinants of these disparities include baseline health status, race and ethnicity, culture, gender identity and expression, socioeconomic status, region or geography, sexual orientation, and age. In order to renew the commitment of the medical community to address health disparities, particularly at the medical school level, we must remind ourselves of the roles of doctors and medical schools as the gatekeepers and the value setters for medicine. Within those roles are responsibilities toward the social mission of working to eliminate health disparities. This effort will require partnerships with communities as well as with academic centers to actively develop and to implement diversity and inclusion strategies. Besides improving the diversity of trainees in the pipeline, access to health care can be improved, and awareness can be raised regarding population-based health inequalities. PMID:23659676

  9. Prioritizing health disparities in medical education to improve care.

    Science.gov (United States)

    Awosogba, Temitope; Betancourt, Joseph R; Conyers, F Garrett; Estapé, Estela S; Francois, Fritz; Gard, Sabrina J; Kaufman, Arthur; Lunn, Mitchell R; Nivet, Marc A; Oppenheim, Joel D; Pomeroy, Claire; Yeung, Howa

    2013-05-01

    Despite yearly advances in life-saving and preventive medicine, as well as strategic approaches by governmental and social agencies and groups, significant disparities remain in health, health quality, and access to health care within the United States. The determinants of these disparities include baseline health status, race and ethnicity, culture, gender identity and expression, socioeconomic status, region or geography, sexual orientation, and age. In order to renew the commitment of the medical community to address health disparities, particularly at the medical school level, we must remind ourselves of the roles of doctors and medical schools as the gatekeepers and the value setters for medicine. Within those roles are responsibilities toward the social mission of working to eliminate health disparities. This effort will require partnerships with communities as well as with academic centers to actively develop and to implement diversity and inclusion strategies. Besides improving the diversity of trainees in the pipeline, access to health care can be improved, and awareness can be raised regarding population-based health inequalities. © 2013 New York Academy of Sciences.

  10. Racial Disparities in Access to Care Under Conditions of Universal Coverage.

    Science.gov (United States)

    Siddiqi, Arjumand A; Wang, Susan; Quinn, Kelly; Nguyen, Quynh C; Christy, Antony Dennis

    2016-02-01

    Racial disparities in access to regular health care have been reported in the U.S., but little is known about the extent of disparities in societies with universal coverage. To investigate the extent of racial disparities in access to care under conditions of universal coverage by observing the association between race and regular access to a doctor in Canada. Racial disparities in access to a regular doctor were calculated using the largest available source of nationally representative data in Canada--the Canadian Community Health Survey. Surveys from 2000-2010 were analyzed in 2014. Multinomial regression analyses predicted odds of having a regular doctor for each racial group compared to whites. Analyses were stratified by immigrant status--Canadian-born versus shorter-term immigrant versus longer-term immigrants--and controlled for sociodemographics and self-rated health. Racial disparities in Canada, a country with universal coverage, were far more muted than those previously reported in the U.S. Only among longer-term Latin American immigrants (OR=1.90, 95% CI=1.45, 2.08) and Canadian-born Aboriginals (OR=1.34, 95% CI=1.22, 1.47) were significant disparities noted. Among shorter-term immigrants, all Asians were more likely than whites, and among longer-term immigrants, South Asians were more like than whites, to have a regular doctor. Universal coverage may have a major impact on reducing racial disparities in access to health care, although among some subgroups, other factors may also play a role above and beyond health insurance. Copyright © 2016 American Journal of Preventive Medicine. Published by Elsevier Inc. All rights reserved.

  11. Transvaginal cervical length and amniotic fluid index: can it predict delivery latency following preterm premature rupture of membranes?

    Science.gov (United States)

    Mehra, Suwan; Amon, Erol; Hopkins, Sarah; Gavard, Jeffrey A; Shyken, Jaye

    2015-03-01

    We sought to determine whether transvaginal cervical length (TVCL), amniotic fluid index (AFI), or a combination of both can predict delivery latency within 7 days in women presenting with preterm premature rupture of membranes (PPROM). This was a prospective observational study of TVCL measurements in 106 singleton pregnancies with PPROM between 23-33 weeks. Delivery latency was defined as the period (in days) from the initial TVCL after PPROM to delivery of the infant, with our primary outcome being delivery within 7 days of TVCL. The independent predictability of significant characteristics for delivery within 7 days was determined using multiple logistic regression. Sensitivity, specificity, and predictive values were used to examine whether the presence of a short TVCL, AFI, or a combination of both affected the risk of delivery within 7 days. Delivery within 7 days occurred in 51/106 (48%) of pregnancies. Median duration (interquartile range) from PPROM to delivery and TVCL to delivery was 8 days (4.0-16.0) and 8 days (3.0-15.0), respectively. Using multiple regression TVCL as a continuous variable (odds ratio, 0.65; 95% confidence interval, 0.44-0.97; P 7 days for TVCL >2 cm alone was 61%. This predictive value changed when analyzed in conjunction with an AFI ≤5 cm and >5 cm at 42% and 89%, respectively. A shorter TVCL and an AFI ≤5 cm independently predict delivery within 7 days in women presenting with PPROM. The combination of an AFI >5 cm and TVCL >2 cm greatly improved the potential to remain undelivered at 7 days following cervical length assessment. These findings may be helpful for counseling and optimizing maternal and neonatal care in women with PPROM. Copyright © 2015 Elsevier Inc. All rights reserved.

  12. Preparing to reach: selecting an adaptive long-latency feedback controller

    OpenAIRE

    Ahmadi-Pajouh, Mohammad Ali; Towhidkhah, Farzad; Shadmehr, Reza

    2012-01-01

    In a voluntary movement, the nervous system specifies not only the motor commands, but also the gains associated with reaction to sensory feedback. For example, suppose that during reaching a perturbation tends to push the hand to the left. With practice, the brain not only learns to produce commands that predictively compensate for the perturbation, but also increases the long-latency reflex gain associated with leftward displacements of the arm. That is, the brain learns a feedback controll...

  13. Protein kinase G confers survival advantage to Mycobacterium tuberculosis during latency-like conditions.

    Science.gov (United States)

    Khan, Mehak Zahoor; Bhaskar, Ashima; Upadhyay, Sandeep; Kumari, Pooja; Rajmani, Raju S; Jain, Preeti; Singh, Amit; Kumar, Dhiraj; Bhavesh, Neel Sarovar; Nandicoori, Vinay Kumar

    2017-09-29

    Protein kinase G (PknG), a thioredoxin-fold-containing eukaryotic-like serine/threonine protein kinase, is a virulence factor in Mycobacterium tuberculosis , required for inhibition of phagolysosomal fusion. Here, we unraveled novel functional facets of PknG during latency-like conditions. We found that PknG mediates persistence under stressful conditions like hypoxia and abets drug tolerance. PknG mutant displayed minimal growth in nutrient-limited conditions, suggesting its role in modulating cellular metabolism. Intracellular metabolic profiling revealed that PknG is necessary for efficient metabolic adaptation during hypoxia. Notably, the PknG mutant exhibited a reductive shift in mycothiol redox potential and compromised stress response. Exposure to antibiotics and hypoxic environment resulted in higher oxidative shift in mycothiol redox potential of PknG mutant compared with the wild type. Persistence during latency-like conditions required kinase activity and thioredoxin motifs of PknG and is mediated through phosphorylation of a central metabolic regulator GarA. Finally, using a guinea pig model of infection, we assessed the in vivo role of PknG in manifestation of disease pathology and established a role for PknG in the formation of stable granuloma, hallmark structures of latent tuberculosis. Taken together, PknG-mediated GarA phosphorylation is important for maintenance of both mycobacterial physiology and redox poise, an axis that is dispensable for survival under normoxic conditions but is critical for non-replicating persistence of mycobacteria. In conclusion, we propose that PknG probably acts as a modulator of latency-associated signals. © 2017 by The American Society for Biochemistry and Molecular Biology, Inc.

  14. Experiences from Implementing a Mobile Multiplayer Real-Time Game for Wireless Networks with High Latency

    Directory of Open Access Journals (Sweden)

    Alf Inge Wang

    2009-01-01

    Full Text Available This paper describes results and experiences from designing, implementing, and testing a multiplayer real-time game over mobile networks with high latency. The paper reports on network latency and bandwidth measurements from playing the game live over GPRS, EDGE, UMTS, and WLAN using the TCP and the UDP protocols. These measurements describe the practical constraints of various wireless networks and protocols when used for mobile multiplayer game purposes. Further, the paper reports on experiences from implementing various approaches to minimize issues related to high latency. Specifically, the paper focuses on a discussion about how much of the game should run locally on the client versus on the server to minimize the load on the mobile device and obtain sufficient consistency in the game. The game was designed to reveal all kinds of implementation issues of mobile network multiplayer games. The goal of the game is for a player to push other players around and into traps where they loose their lives. The game relies heavily on collision detection between the players and game objects. The paper presents experiences from experimenting with various approaches that can be used to handle such collisions, and highlights the advantages and disadvantages of the various approaches.

  15. Dynamic visual noise reduces confidence in short-term memory for visual information.

    Science.gov (United States)

    Kemps, Eva; Andrade, Jackie

    2012-05-01

    Previous research has shown effects of the visual interference technique, dynamic visual noise (DVN), on visual imagery, but not on visual short-term memory, unless retention of precise visual detail is required. This study tested the prediction that DVN does also affect retention of gross visual information, specifically by reducing confidence. Participants performed a matrix pattern memory task with three retention interval interference conditions (DVN, static visual noise and no interference control) that varied from trial to trial. At recall, participants indicated whether or not they were sure of their responses. As in previous research, DVN did not impair recall accuracy or latency on the task, but it did reduce recall confidence relative to static visual noise and no interference. We conclude that DVN does distort visual representations in short-term memory, but standard coarse-grained recall measures are insensitive to these distortions.

  16. Gender disparities in completing school education in India: Analyzing regional variations

    OpenAIRE

    Husain, Zakir

    2010-01-01

    Is gender disparity greater in North India? This paper seeks to answer this question by examining gender differences in probability of completing school education across regions in India. A Gender Disparity Index is calculated using National Sample Survey Organization unit level data from the 61st Round and regional variations in this index analyzed to examine the hypothesis that gender disparity is greater in the North, comparative to the rest of India. This is followed by an econometric exe...

  17. Contribution of screening and survival differences to racial disparities in colorectal cancer rates

    Science.gov (United States)

    Lansdorp-Vogelaar, Iris; Kuntz, Karen M.; Knudsen, Amy B.; van Ballegooijen, Marjolein; Zauber, Ann G.; Jemal, Ahmedin

    2012-01-01

    Background Considerable disparities exist in colorectal cancer (CRC) incidence and mortality rates between blacks and whites in the US. We estimated how much of these disparities could be explained by differences in CRC screening and stage-specific relative CRC survival. Methods We used the MISCAN-Colon microsimulation model to estimate CRC incidence and mortality rates in blacks aged 50 years and older from 1975 to 2007 assuming they had: 1) the same trends in screening rates as whites instead of observed screening rates (incidence and mortality); and 2) the same trends in stage-specific relative CRC survival rates as whites instead of observed (mortality only); and 3) a combination of both. The racial disparities in CRC incidence and mortality rates attributable to differences in screening and/or stage-specific relative CRC survival were then calculated by comparing rates from these scenarios to the observed black rates. Results Differences in screening account for 42% of disparity in CRC incidence and 19% of disparity in CRC mortality between blacks and whites. 36% of the disparity in CRC mortality could be attributed to differences in stage-specific relative CRC survival. Together screening and survival explained a little over 50% of the disparity in CRC mortality between blacks and whites. Conclusion Differences in screening and relative CRC survival are responsible for a considerable proportion of the observed disparities in CRC incidence and mortality rates between blacks and whites. Impact Enabling blacks to achieve equal access to care as whites could substantially reduce the racial disparities in CRC burden. PMID:22514249

  18. Variable disparity-motion estimation based fast three-view video coding

    Science.gov (United States)

    Bae, Kyung-Hoon; Kim, Seung-Cheol; Hwang, Yong Seok; Kim, Eun-Soo

    2009-02-01

    In this paper, variable disparity-motion estimation (VDME) based 3-view video coding is proposed. In the encoding, key-frame coding (KFC) based motion estimation and variable disparity estimation (VDE) for effectively fast three-view video encoding are processed. These proposed algorithms enhance the performance of 3-D video encoding/decoding system in terms of accuracy of disparity estimation and computational overhead. From some experiments, stereo sequences of 'Pot Plant' and 'IVO', it is shown that the proposed algorithm's PSNRs is 37.66 and 40.55 dB, and the processing time is 0.139 and 0.124 sec/frame, respectively.

  19. 75 FR 66114 - National Center on Minority Health and Health Disparities; Notice of Closed Meeting

    Science.gov (United States)

    2010-10-27

    ... Health and Health Disparities; Notice of Closed Meeting Pursuant to section 10(d) of the Federal Advisory... and Health Disparities Special Emphasis Panel; NCMHD Health Disparities Research on Minority and... Review Officer, National Institute on Minority Health and Health Disparities, 6707 Democracy Boulevard...

  20. 75 FR 12766 - National Center on Minority Health and Health Disparities; Notice of Closed Meetings

    Science.gov (United States)

    2010-03-17

    ... Health and Health Disparities; Notice of Closed Meetings Pursuant to section 10(d) of the Federal... and Health Disparities Special Emphasis Panel Loan Repayment Program for Health Disparities Research... Review, National Center on Minority Health and Health Disparities, 6707 Democracy Boulevard, Suite 800...

  1. Response Latency as a Function of Hypothesis-Testing Strategies in Concept Identification

    Science.gov (United States)

    Fink, Richard T.

    1972-01-01

    The ability of M. Levine's subset-sampling assumptions to account for the decrease in response latency following the trial of the last error was investigated by employing a distributed stimulus set composed of four binary dimensions and a procedure which required Ss to make an overt response in order to sample each dimension. (Author)

  2. Disparities in criminal court referrals to drug treatment and prison for minority men.

    Science.gov (United States)

    Nicosia, Nancy; Macdonald, John M; Arkes, Jeremy

    2013-06-01

    We investigated the extent to which racial/ethnic disparities in prison and diversion to drug treatment were explained by current arrest and criminal history characteristics among drug-involved offenders, and whether those disparities decreased after California's Proposition 36, which mandated first- and second-time nonviolent drug offenders drug treatment instead of prison. We analyzed administrative data on approximately 170,000 drug-involved arrests in California between 1995 and 2005. We examined odds ratios from logistic regressions for prison and diversion across racial/ethnic groups before and after Proposition 36. We found significant disparities in prison and diversion for Blacks and Hispanics relative to Whites. These disparities decreased after controlling for current arrest and criminal history characteristics for Blacks. Proposition 36 was also associated with a reduction in disparities, but more so for Hispanics than Blacks. Disparities in prison and diversion to drug treatment among drug-involved offenders affect hundreds of thousands of citizens and might reinforce imbalances in criminal justice and health outcomes. Our study indicated that standardized criminal justice policies that improved access to drug treatment might contribute to alleviating some share of these disparities.

  3. Feminist intersectionality: bringing social justice to health disparities research.

    Science.gov (United States)

    Rogers, Jamie; Kelly, Ursula A

    2011-05-01

    The principles of autonomy, beneficence, non-maleficence, and justice are well established ethical principles in health research. Of these principles, justice has received less attention by health researchers. The purpose of this article is to broaden the discussion of health research ethics, particularly the ethical principle of justice, to include societal considerations--who and what are studied and why?--and to critique current applications of ethical principles within this broader view. We will use a feminist intersectional approach in the context of health disparities research to firmly establish inseparable links between health research ethics, social action, and social justice. The aim is to provide an ethical approach to health disparities research that simultaneously describes and seeks to eliminate health disparities. © The Author(s) 2011

  4. Interactions between Attention and Visual Short-Term Memory (VSTM): What Can Be Learnt from Individual and Developmental Differences?

    Science.gov (United States)

    Astle, Duncan E.; Scerif, Gaia

    2011-01-01

    An ever increasing amount of research in the fields of developmental psychology and adult cognitive neuroscience explores attentional control as a driver of visual short-term and working memory capacity limits ("VSTM" and "VWM", respectively). However, these literatures have thus far been disparate: they use different measures or different labels,…

  5. 75 FR 9421 - National Center on Minority Health and Health Disparities; Notice of Closed Meeting

    Science.gov (United States)

    2010-03-02

    ... Health and Health Disparities; Notice of Closed Meeting Pursuant to section 10(d) of the Federal Advisory... and Health Disparities Special Emphasis Panel; Loan Repayment Program for Health Disparities Research..., National Center on Minority Health and Health Disparities, 6707 Democracy Boulevard, Suite 800, Bethesda...

  6. Fetal MEG evoked response latency from beamformer with random field theory.

    Science.gov (United States)

    McCubbin, J; Vrba, J; Murphy, P; Temple, J; Eswaran, H; Lowery, C L; Preissl, H

    2010-01-01

    Analysis of fetal magnetoencephalographic brain recordings is restricted by low signal to noise ratio (SNR) and non-stationarity of the sources. Beamformer techniques have been applied to improve SNR of fetal evoked responses. However, until now the effect of non-stationarity was not taken into account in detail, because the detection of evoked responses is in most cases determined by averaging a large number of trials. We applied a windowing technique to improve the stationarity of the data by using short time segments recorded during a flash-evoked study. In addition, we implemented a random field theory approach for more stringent control of false-positives in the statistical parametric map of the search volume for the beamformer. The search volume was based on detailed individual fetal/maternal biometrics from ultrasound scans and fetal heart localization. Average power over a sliding window within the averaged evoked response against a randomized average background power was used as the test z-statistic. The significance threshold was set at 10% over all members of a contiguous cluster of voxels. There was at least one significant response for 62% of fetal and 95% of newborn recordings with gestational age (GA) between 28 and 45 weeks from 29 subjects. We found that the latency was either substantially unchanged or decreased with increasing GA for most subjects, with a nominal rate of about -11 ms/week. These findings support the anticipated neurophysiological development, provide validation for the beamformer model search as a methodology, and may lead to a clinical test for fetal cognitive development.

  7. Solving Disparities Through Payment And Delivery System Reform: A Program To Achieve Health Equity.

    Science.gov (United States)

    DeMeester, Rachel H; Xu, Lucy J; Nocon, Robert S; Cook, Scott C; Ducas, Andrea M; Chin, Marshall H

    2017-06-01

    Payment systems generally do not directly encourage or support the reduction of health disparities. In 2013 the Finding Answers: Solving Disparities through Payment and Delivery System Reform program of the Robert Wood Johnson Foundation sought to understand how alternative payment models might intentionally incorporate a disparities-reduction component to promote health equity. A qualitative analysis of forty proposals to the program revealed that applicants generally did not link payment reform tightly to disparities reduction. Most proposed general pay-for-performance, global payment, or shared savings plans, combined with multicomponent system interventions. None of the applicants proposed making any financial payments contingent on having successfully reduced disparities. Most applicants did not address how they would optimize providers' intrinsic and extrinsic motivation to reduce disparities. A better understanding of how payment and care delivery models might be designed and implemented to reduce health disparities is essential. Project HOPE—The People-to-People Health Foundation, Inc.

  8. Disparities in Birth Weight and Gestational Age by Ethnic Ancestry in South American countries

    Science.gov (United States)

    Wehby, George L.; Gili, Juan A.; Pawluk, Mariela; Castilla, Eduardo E.; López-Camelo, Jorge S.

    2015-01-01

    Objective We examine disparities in birth weight and gestational age by ethnic ancestry in 2000–2011 in eight South American countries. Methods The sample included 60480 singleton live-births. Regression models were estimated to evaluate differences in birth outcomes by ethnic ancestry controlling for time trends. Results Significant disparities were found in seven countries. In four countries – Brazil, Ecuador, Uruguay, and Venezuela – we found significant disparities in both low birth weight and preterm birth. Disparities in preterm birth alone were observed in Argentina, Bolivia, and Colombia. Several differences in continuous birth weight, gestational age, and fetal growth rate were also observed. There were no systematic patterns of disparities between the evaluated ethnic ancestry groups across the study countries, in that no racial/ethnic group consistently had the best or worst outcomes in all countries. Conclusions Racial/ethnic disparities in infant health are common in several South American countries. Differences across countries suggest that racial/ethnic disparities are driven by social and economic mechanisms. Researchers and policymakers should acknowledge these disparities and develop research and policy programs to effectively target them. PMID:25542227

  9. 12-bit 32 channel 500 MS/s low-latency ADC for particle accelerators real-time control

    Science.gov (United States)

    Karnitski, Anton; Baranauskas, Dalius; Zelenin, Denis; Baranauskas, Gytis; Zhankevich, Alexander; Gill, Chris

    2017-09-01

    Particle beam control systems require real-time low latency digital feedback with high linearity and dynamic range. Densely packed electronic systems employ high performance multichannel digitizers causing excessive heat dissipation. Therefore, low power dissipation is another critical requirement for these digitizers. A described 12-bit 500 MS/s ADC employs a sub-ranging architecture based on a merged sample & hold circuit, a residue C-DAC and a shared 6-bit flash core ADC. The core ADC provides a sequential coarse and fine digitization featuring a latency of two clock cycles. The ADC is implemented in a 28 nm CMOS process and consumes 4 mW of power per channel from a 0.9 V supply (interfacing and peripheral circuits are excluded). Reduced power consumption and small on-chip area permits the implementation of 32 ADC channels on a 10.7 mm2 chip. The ADC includes a JESD204B standard compliant output data interface operated at the 7.5 Gbps/ch rate. To minimize the data interface related time latency, a special feature permitting to bypass the JESD204B interface is built in. DoE Phase I Award Number: DE-SC0017213.

  10. The first 50Myr of dinosaur evolution: macroevolutionary pattern and morphological disparity.

    Science.gov (United States)

    Brusatte, Stephen L; Benton, Michael J; Ruta, Marcello; Lloyd, Graeme T

    2008-12-23

    The evolutionary radiation of dinosaurs in the Late Triassic and Early Jurassic was a pivotal event in the Earth's history but is poorly understood, as previous studies have focused on vague driving mechanisms and have not untangled different macroevolutionary components (origination, diversity, abundance and disparity). We calculate the morphological disparity (morphospace occupation) of dinosaurs throughout the Late Triassic and Early Jurassic and present new measures of taxonomic diversity. Crurotarsan archosaurs, the primary dinosaur 'competitors', were significantly more disparate than dinosaurs throughout the Triassic, but underwent a devastating extinction at the Triassic-Jurassic boundary. However, dinosaur disparity showed only a slight non-significant increase after this event, arguing against the hypothesis of ecological release-driven morphospace expansion in the Early Jurassic. Instead, the main jump in dinosaur disparity occurred between the Carnian and Norian stages of the Triassic. Conversely, dinosaur diversity shows a steady increase over this time, and measures of diversification and faunal abundance indicate that the Early Jurassic was a key episode in dinosaur evolution. Thus, different aspects of the dinosaur radiation (diversity, disparity and abundance) were decoupled, and the overall macroevolutionary pattern of the first 50Myr of dinosaur evolution is more complex than often considered.

  11. Analysis of Latency and MAC-layer Performance for Class A LoRaWAN

    DEFF Research Database (Denmark)

    Sørensen, René Brandborg; Kim, Dong Min; Nielsen, Jimmy Jessen

    2017-01-01

    We propose analytical models that allow to investigate the performance of Long Range Wide Area Network (LoRaWAN) uplink in terms of latency, collision rate, and throughput under the constraints of the regulatory duty cycling, when assuming exponential inter-arrival times. Our models take into acc...

  12. Program of radiological monitoring environmental a nuclear facility in latency

    International Nuclear Information System (INIS)

    Blas, A. de; Riego, A.; Batalla, E.; Tapia, C.; Garcia, R.; Sanchez, J.; Toral, J.

    2013-01-01

    This paper presents the Radiological Environmental Monitoring program of the Vandellos I nuclear power plant in the latency period. This facility was dismantled to level 2, as defined by the International Atomic Energy Agency. The program is an adaptation of the implanted one during the dismantling, taking into account the isotopes that may be present, as well as the main transfer routes. Along with the description of the program the results obtained in the latent period from 2005 until 2012 are presented.

  13. Efficiency of rate and latency coding with respect to metabolic cost and time.

    Science.gov (United States)

    Levakova, Marie

    2017-11-01

    Recent studies on the theoretical performance of latency and rate code in single neurons have revealed that the ultimate accuracy is affected in a nontrivial way by aspects such as the level of spontaneous activity of presynaptic neurons, amount of neuronal noise or the duration of the time window used to determine the firing rate. This study explores how the optimal decoding performance and the corresponding conditions change when the energy expenditure of a neuron in order to spike and maintain the resting membrane potential is accounted for. It is shown that a nonzero amount of spontaneous activity remains essential for both the latency and the rate coding. Moreover, the optimal level of spontaneous activity does not change so much with respect to the intensity of the applied stimulus. Furthermore, the efficiency of the temporal and the rate code converge to an identical finite value if the neuronal activity is observed for an unlimited period of time. Copyright © 2017 Elsevier B.V. All rights reserved.

  14. Can universal coverage eliminate health disparities? Reversal of disparate injury outcomes in elderly insured minorities.

    Science.gov (United States)

    Ramirez, Michelle; Chang, David C; Rogers, Selwyn O; Yu, Peter T; Easterlin, Molly; Coimbra, Raul; Kobayashi, Leslie

    2013-06-15

    Health outcome disparities in racial minorities are well documented. However, it is unknown whether such disparities exist among elderly injured patients. We hypothesized that such disparities might be reduced in the elderly owing to insurance coverage under Medicare. We investigated this issue by comparing the trauma outcomes in young and elderly patients in California. A retrospective analysis of the California Office of Statewide Health Planning and Development hospital discharge database was performed for all publicly available years from 1995 to 2008. Trauma admissions were identified by International Classification of Disease, Ninth Revision, primary diagnosis codes from 800 to 959, with certain exclusions. Multivariate analysis examined the adjusted risk of in-hospital mortality in young (<65 y) and elderly (≥65 y) patients, controlling for age, gender, injury severity as measured by the survival risk ratio, Charlson comorbidity index, insurance status, calendar year, and teaching hospital status. A total of 1,577,323 trauma patients were identified. Among the young patients, the adjusted odds ratio of death relative to non-Hispanic whites for blacks, Hispanics, Asians, and Native Americans/others was 1.2, 1.2, 0.90, and 0.78, respectively. The corresponding adjusted odds ratios of death for elderly patients were 0.78, 0.87, 0.92, and 0.61. Young black and Hispanic trauma patients had greater mortality risks relative to non-Hispanic white patients. Interestingly, elderly black and Hispanic patients had lower mortality risks compared with non-Hispanic whites. Copyright © 2013 Elsevier Inc. All rights reserved.

  15. Disparities in the survivorship experience among Latina survivors of breast cancer.

    Science.gov (United States)

    Olagunju, Tinuke O; Liu, Yihang; Liang, Li-Jung; Stomber, James M; Griggs, Jennifer J; Ganz, Patricia A; Thind, Amardeep; Maly, Rose C

    2018-04-06

    The authors investigated disparities in the survivorship experience among Latinas with breast cancer (BC) in comparison with non-Latinas. A cross-sectional bilingual telephone survey was conducted among 212 Latina and non-Latina women within 10 to 24 months after a diagnosis of BC (AJCC TNM staging system stage 0-III) at 2 Los Angeles County public hospitals. Data were collected using the Preparing for Life as a (New) Survivor (PLANS) scale, Perceived Efficacy in Patient-Physician Interactions Questionnaire (PEPPI), Breast Cancer Prevention Trial (BCPT) Symptom Checklist, Satisfaction with Care and Information Scale, Consumer Assessment of Healthcare Providers and Systems (CAHPS) tool, Charlson Comorbidity Index adapted for patient self-report, and the 12-item Short Form Health Survey. Controlling variables included age, stage as determined by the American Joint Committee on Cancer (AJCC) TNM staging system, educational level, and study site in multivariate analyses. The mean ages of Latinas and non-Latinas were 51.5 years and 56.6 years, respectively. Compared with non-Latinas, Latinas reported less BC survivorship knowledge (27.3 vs 30.7; Psatisfaction with BC survivorship care (9.6 vs 8.8; P = .298), or their discussion with physicians (9.6 vs 8.1; P = .07). These ethnic group differences persisted in multivariate analyses, with the exception of PEPPI. Latina survivors of BC experienced disparities in BC knowledge and satisfaction with information received, but believed themselves to be prepared for survivorship and were as satisfied with providers, care received, and discussions with physicians as non-Latinas. Cancer 2018. © 2018 American Cancer Society. © 2018 American Cancer Society.

  16. Trust in physicians and racial disparities in HIV care.

    Science.gov (United States)

    Saha, Somnath; Jacobs, Elizabeth A; Moore, Richard D; Beach, Mary Catherine

    2010-07-01

    Mistrust among African Americans is often considered a potential source of racial disparities in HIV care. We sought to determine whether greater trust in one's provider among African-American patients mitigates racial disparities. We analyzed data from 1,104 African-American and 201 white patients participating in a cohort study at an urban, academic HIV clinic between 2005 and 2008. African Americans expressed lower levels of trust in their providers than did white patients (8.9 vs. 9.4 on a 0-10 scale; p African Americans were also less likely than whites to be receiving antiretroviral therapy (ART) when eligible (85% vs. 92%; p = 0.02), to report complete ART adherence over the prior 3 days (83% vs. 89%; p = 0.005), and to have a suppressed viral load (40% vs. 47%; p = 0.04). Trust in one's provider was not associated with receiving ART or with viral suppression but was significantly associated with adherence. African Americans who expressed less than complete trust in their providers (0-9 of 10) had lower ART adherence than did whites (adjusted OR, 0.40; 95% CI, 0.25-0.66). For African Americans who expressed complete trust in their providers (10 of 10), the racial disparity in adherence was less prominent but still substantial (adjusted OR, 0.59; 95% CI, 0.36-0.95). Trust did not affect disparities in receipt of ART or viral suppression. Our findings suggest that enhancing trust in patient-provider relationships for African-American patients may help reduce disparities in ART adherence and the outcomes associated with improved adherence.

  17. Low-latency analysis pipeline for compact binary coalescences in the advanced gravitational wave detector era

    International Nuclear Information System (INIS)

    Adams, T; Buskulic, D; Germain, V; Marion, F; Mours, B; Guidi, G M; Montani, M; Piergiovanni, F; Wang, G

    2016-01-01

    The multi-band template analysis (MBTA) pipeline is a low-latency coincident analysis pipeline for the detection of gravitational waves (GWs) from compact binary coalescences. MBTA runs with a low computational cost, and can identify candidate GW events online with a sub-minute latency. The low computational running cost of MBTA also makes it useful for data quality studies. Events detected by MBTA online can be used to alert astronomical partners for electromagnetic follow-up. We outline the current status of MBTA and give details of recent pipeline upgrades and validation tests that were performed in preparation for the first advanced detector observing period. The MBTA pipeline is ready for the outset of the advanced detector era and the exciting prospects it will bring. (paper)

  18. Age-Related Racial Disparity in Suicide Rates Among U.S. Youth

    Science.gov (United States)

    ... May 30, 2018 Age-Related Racial Disparity in Youth Suicide Rates May 21, 2018 News by Year 2018 ... May 30, 2018 Age-Related Racial Disparity in Youth Suicide Rates May 21, 2018 News by Year 2018 ...

  19. Friend Effects and Racial Disparities in Academic Achievement

    Directory of Open Access Journals (Sweden)

    Jennifer Flashman

    2014-07-01

    Full Text Available Racial disparities in achievement are a persistent fact of the US educational system. An often cited but rarely directly studied explanation for these disparities is that adolescents from different racial and ethnic backgrounds are exposed to different peers and have different friends. In this article I identify the impact of friends on racial and ethnic achievement disparities. Using data from Add Health and an instrumental variable approach, I show that the achievement characteristics of youths’ friends drive friend effects; adolescents with friends with higher grades are more likely to increase their grades compared to those with lower-achieving friends. Although these effects do not differ across race/ethnicity, given differences in friendship patterns, if black and Latino adolescents had friends with the achievement characteristics of white students, the GPA gap would be 17 to 19 percent smaller. Although modest, this effect represents an important and often overlooked source of difference among black and Latino youth.

  20. Health Disparities Score Composite of Youth and Parent Dyads from an Obesity Prevention Intervention: iCook 4-H

    Directory of Open Access Journals (Sweden)

    Melissa D. Olfert

    2018-05-01

    Full Text Available iCook 4-H is a lifestyle intervention to improve diet, physical activity and mealtime behavior. Control and treatment dyads (adult primary meal preparer and a 9–10-year-old youth completed surveys at baseline and 4, 12, and 24 months. A Health Disparity (HD score composite was developed utilizing a series of 12 questions (maximum score = 12 with a higher score indicating a more severe health disparity. Questions came from the USDA short form U.S. Household Food Security Survey (5, participation in food assistance programs (1, food behavior (2, level of adult education completed (1, marital status (1, and race (1 adult and 1 child. There were 228 dyads (control n = 77; treatment n = 151 enrolled in the iCook 4-H study. Baseline HD scores were 3.00 ± 2.56 among control dyads and 2.97 ± 2.91 among treatment dyads, p = 0.6632. There was a significant decline in the HD score of the treatment group from baseline to 12 months (p = 0.0047 and baseline to 24 months (p = 0.0354. A treatment by 12-month time interaction was found (baseline mean 2.97 ± 2.91 vs. 12-month mean 1.78 ± 2.31; p = 0.0406. This study shows that behavioral change interventions for youth and adults can help improve factors that impact health equity; although, further research is needed to validate this HD score as a measure of health disparities across time.

  1. Asthma Management Disparities: A Photovoice Investigation with African American Youth

    Science.gov (United States)

    Evans-Agnew, Robin

    2016-01-01

    Disparities in asthma management are a burden on African American youth. The objective of this study is to describe and compare the discourses of asthma management disparities (AMDs) in African American adolescents in Seattle to existing youth-related asthma policies in Washington State. Adolescents participated in a three-session photovoice…

  2. Social justice, health disparities, and culture in the care of the elderly.

    Science.gov (United States)

    Dilworth-Anderson, Peggye; Pierre, Geraldine; Hilliard, Tandrea S

    2012-01-01

    Older minority Americans experience worse health outcomes than their white counterparts, exhibiting the need for social justice in all areas of their health care. Justice, fairness, and equity are crucial to minimizing conditions that adversely affect the health of individuals and communities. In this paper, Alzheimer's disease (AD) is used as an example of a health care disparity among elderly Americans that requires social justice interventions. Cultural factors play a crucial role in AD screening, diagnosis, and access to care, and are often a barrier to support and equality for minority communities. The "conundrum of health disparities" refers to the interplay between disparity, social justice, and cultural interpretation, and encourages researchers to understand both (1) disparity caused by economic and structural barriers to access, treatment, and diagnosis, and (2) disparity due to cultural interpretation of disease, in order to effectively address health care issues and concerns among elderly Americans. © 2012 American Society of Law, Medicine & Ethics, Inc.

  3. Organizational Change Management For Health Equity: Perspectives From The Disparities Leadership Program.

    Science.gov (United States)

    Betancourt, Joseph R; Tan-McGrory, Aswita; Kenst, Karey S; Phan, Thuy Hoai; Lopez, Lenny

    2017-06-01

    Leaders of health care organizations need to be prepared to improve quality and achieve equity in today's health care environment characterized by a focus on achieving value and addressing disparities in a diverse population. To help address this need, the Disparities Solutions Center at Massachusetts General Hospital launched the Disparities Leadership Program in 2007. The leadership program is an ongoing, year-long, executive education initiative that trains leaders from hospitals, health plans, and health centers to improve quality and eliminate racial and ethnic disparities in health care. Feedback from participating organizations demonstrates that health care leaders seem to possess knowledge about what disparities are and about what should be done to eliminate them. Data collection, performance measurement, and multifaceted interventions remain the tools of the trade. However, the barriers to success are lack of leadership buy-in, organizational prioritization, energy, and execution, which can be addressed through organizational change management strategies. Project HOPE—The People-to-People Health Foundation, Inc.

  4. Linking Diversity and Disparity Measures

    Directory of Open Access Journals (Sweden)

    Sahadeb Sarkar

    2012-07-01

    Full Text Available Normal 0 false false false EN-US X-NONE X-NONE /* Style Definitions */ table.MsoNormalTable {mso-style-name:"Table Normal"; mso-tstyle-rowband-size:0; mso-tstyle-colband-size:0; mso-style-noshow:yes; mso-style-priority:99; mso-style-parent:""; mso-padding-alt:0in 5.4pt 0in 5.4pt; mso-para-margin:0in; mso-para-margin-bottom:.0001pt; mso-pagination:widow-orphan; font-size:10.0pt; font-family:"Times New Roman","serif";} The purpose of this paper is to examine links between the diversity measures (Patil and Taillie 1982 and the disparity measures (Lindsay 1994, quantities apparently developed for somewhat different purposes. We demonstrate that numerous diversity measures satisfying all the desirable criteria mentioned by Patil and Taillie can be defined by the generating functions of certain disparities and the associated residual adjustment functions. This provides the statistician and the ecologist a wide class of flexible indices for the statistical measurement of diversity.

  5. Socioeconomic Disparities and Health: Impacts and Pathways

    Science.gov (United States)

    Kondo, Naoki

    2012-01-01

    Growing socioeconomic disparity is a global concern, as it could affect population health. The author and colleagues have investigated the health impacts of socioeconomic disparities as well as the pathways that underlie those disparities. Our meta-analysis found that a large population has risks of mortality and poor self-rated health that are attributable to income inequality. The study results also suggested the existence of threshold effects (ie, a threshold of income inequality over which the adverse impacts on health increase), period effects (ie, the potential for larger impacts in later years, specifically after the 1990s), and lag effects between income inequality and health outcomes. Our other studies using Japanese national representative survey data and a large-scale cohort study of Japanese older adults (AGES cohort) support the relative deprivation hypothesis, namely, that invidious social comparisons arising from relative deprivation in an unequal society adversely affect health. A study with a natural experiment design found that the socioeconomic gradient in self-rated health might actually have become shallower after the 1997–98 economic crisis in Japan, due to smaller health improvements among middle-class white-collar workers and middle/upper-income workers. In conclusion, income inequality might have adverse impacts on individual health, and psychosocial stress due to relative deprivation may partially explain those impacts. Any study of the effects of macroeconomic fluctuations on health disparities should also consider multiple potential pathways, including expanding income inequality, changes in the labor market, and erosion of social capital. Further studies are needed to attain a better understanding of the social determinants of health in a rapidly changing society. PMID:22156290

  6. Socioeconomic disparities and health: impacts and pathways.

    Science.gov (United States)

    Kondo, Naoki

    2012-01-01

    Growing socioeconomic disparity is a global concern, as it could affect population health. The author and colleagues have investigated the health impacts of socioeconomic disparities as well as the pathways that underlie those disparities. Our meta-analysis found that a large population has risks of mortality and poor self-rated health that are attributable to income inequality. The study results also suggested the existence of threshold effects (ie, a threshold of income inequality over which the adverse impacts on health increase), period effects (ie, the potential for larger impacts in later years, specifically after the 1990s), and lag effects between income inequality and health outcomes. Our other studies using Japanese national representative survey data and a large-scale cohort study of Japanese older adults (AGES cohort) support the relative deprivation hypothesis, namely, that invidious social comparisons arising from relative deprivation in an unequal society adversely affect health. A study with a natural experiment design found that the socioeconomic gradient in self-rated health might actually have become shallower after the 1997-98 economic crisis in Japan, due to smaller health improvements among middle-class white-collar workers and middle/upper-income workers. In conclusion, income inequality might have adverse impacts on individual health, and psychosocial stress due to relative deprivation may partially explain those impacts. Any study of the effects of macroeconomic fluctuations on health disparities should also consider multiple potential pathways, including expanding income inequality, changes in the labor market, and erosion of social capital. Further studies are needed to attain a better understanding of the social determinants of health in a rapidly changing society.

  7. Racial/Ethnic Disparities in Nursing Home Quality of Life Deficiencies, 2001 to 2011

    Directory of Open Access Journals (Sweden)

    Lauren J. Campbell MA

    2016-06-01

    Full Text Available Objectives: Racial/ethnic disparities in nursing homes (NHs are associated with lower quality of care, and state Medicaid payment policies may influence NH quality. However, no studies analyzing disparities in NH quality of life (QoL exist. Therefore, this study aims to estimate associations at the NH level between average number of QoL deficiencies and concentrations of racial/ethnic minority residents, and to identify effects of state Medicaid payment policies on racial/ethnic disparities. Method: Multivariable Poisson regression with NH random effects was used to determine the association between NH minority concentration in 2000 to 2010 and average number of QoL deficiencies in 2001 to 2011 at the NH level, and the effect of state NH payment policies on QoL deficiencies and racial/ethnic disparities in QoL deficiencies across NH minority concentrations. Results: Racial/ethnic disparities in QoL between high and low minority concentration NHs decrease over time, but are not eliminated. Case mix payment was associated with an increased disparity between high and low minority concentration NHs in QoL deficiencies. Discussion: NH managers and policy makers should consider initiatives targeting minority residents or low-performing NHs with higher minority concentrations for improvement to reduce disparities and address QoL deficiencies.

  8. The role of health-related behaviors in the socioeconomic disparities in oral health.

    Science.gov (United States)

    Sabbah, Wael; Tsakos, Georgios; Sheiham, Aubrey; Watt, Richard G

    2009-01-01

    This study aimed to examine the socioeconomic disparities in health-related behaviors and to assess if behaviors eliminate socioeconomic disparities in oral health in a nationally representative sample of adult Americans. Data are from the US Third National Health and Nutrition Examination Survey (1988-1994). Behaviors were indicated by smoking, dental visits, frequency of eating fresh fruits and vegetables and extent of calculus, used as a marker for oral hygiene. Oral health outcomes were gingival bleeding, loss of periodontal attachment, tooth loss and perceived oral health. Education and income indicated socioeconomic position. Sex, age, ethnicity, dental insurance and diabetes were adjusted for in the regression analysis. Regression analysis was used to assess socioeconomic disparities in behaviors. Regression models adjusting and not adjusting for behaviors were compared to assess the change in socioeconomic disparities in oral health. The results showed clear socioeconomic disparities in all behaviors. After adjusting for behaviors, the association between oral health and socioeconomic indicators attenuated but did not disappear. These findings imply that improvement in health-related behaviors may lessen, but not eliminate socioeconomic disparities in oral health, and suggest the presence of more complex determinants of these disparities which should be addressed by oral health preventive policies.

  9. Examining Sexual Orientation Disparities in Unmet Medical Needs among Men and Women

    OpenAIRE

    Everett, Bethany G.; Mollborn, Stefanie

    2013-01-01

    Using the National Longitudinal Study of Adolescent Health (N = 13,810), this study examines disparities in unmet medical needs by sexual orientation identity during young adulthood. We use binary logistic regression and expand Andersen’s health care utilization framework to identify factors that shape disparities in unmet medical needs by sexual orientation. We also investigate whether the well-established gender disparity in health-seeking behaviors among heterosexual persons holds for sexu...

  10. Gender Disparity at Elementary Education Level in Jammu and Kashmir: An Exploratory Study

    Science.gov (United States)

    Gul, Showkeen Bilal Ahmad; Khan, Zebun Nisa

    2014-01-01

    This paper is based on a study to explore gender disparity at elementary education level in Jammu and Kashmir. Gender disparity in education refers to differences in outcomes observed between two sexes. Education disparities can be seen in different enrolment rates, dropout rates, and survival rates among the sexes. The central government and…

  11. The influence of health disparities on targeting cancer prevention efforts.

    Science.gov (United States)

    Zonderman, Alan B; Ejiogu, Ngozi; Norbeck, Jennifer; Evans, Michele K

    2014-03-01

    Despite the advances in cancer medicine and the resultant 20% decline in cancer death rates for Americans since 1991, there remain distinct cancer health disparities among African Americans, Hispanics, Native Americans, and the those living in poverty. Minorities and the poor continue to bear the disproportionate burden of cancer, especially in terms of stage at diagnosis, incidence, and mortality. Cancer health disparities are persistent reminders that state-of-the-art cancer prevention, diagnosis, and treatment are not equally effective for and accessible to all Americans. The cancer prevention model must take into account the phenotype of accelerated aging associated with health disparities as well as the important interplay of biological and sociocultural factors that lead to disparate health outcomes. The building blocks of this prevention model will include interdisciplinary prevention modalities that encourage partnerships across medical and nonmedical entities, community-based participatory research, development of ethnically and racially diverse research cohorts, and full actualization of the prevention benefits outlined in the 2010 Patient Protection and Affordable Care Act. However, the most essential facet should be a thoughtful integration of cancer prevention and screening into prevention, screening, and disease management activities for hypertension and diabetes mellitus because these chronic medical illnesses have a substantial prevalence in populations at risk for cancer disparities and cause considerable comorbidity and likely complicate effective treatment and contribute to disproportionate cancer death rates. Published by Elsevier Inc.

  12. Trends in racial disparities for asthma outcomes among children 0 to 17 years, 2001-2010.

    Science.gov (United States)

    Akinbami, Lara J; Moorman, Jeanne E; Simon, Alan E; Schoendorf, Kenneth C

    2014-09-01

    Racial disparities in childhood asthma have been a long-standing target for intervention, especially disparities in hospitalization and mortality. Describe trends in racial disparities in asthma outcomes using both traditional population-based rates and at-risk rates (based on the estimated number of children with asthma) to account for prevalence differences between race groups. Estimates of asthma prevalence and outcomes (emergency department [ED] visits, hospitalizations, and deaths) were calculated from national data for 2001 to 2010 for black and white children. Trends were calculated using weighted loglinear regression, and changes in racial disparities over time were assessed using Joinpoint. Disparities in asthma prevalence between black and white children increased from 2001 to 2010; at the end of this period, black children were twice as likely as white children to have asthma. Population-based rates showed that disparities in asthma outcomes remained stable (ED visits and hospitalizations) or increased (asthma attack prevalence, deaths). In contrast, analysis with at-risk rates, which account for differences in asthma prevalence, showed that disparities in asthma outcomes remained stable (deaths), decreased (ED visits, hospitalizations), or did not exist (asthma attack prevalence). Using at-risk rates to assess racial disparities in asthma outcomes accounts for prevalence differences between black and white children, and adds another perspective to the population-based examination of asthma disparities. An at-risk rate analysis shows that among children with asthma, there is no disparity for asthma attack prevalence and that progress has been made in decreasing disparities in asthma ED visit and hospitalization rates. Published by Elsevier Inc.

  13. Implementing the Institute of Medicine definition of disparities: an application to mental health care.

    Science.gov (United States)

    McGuire, Thomas G; Alegria, Margarita; Cook, Benjamin L; Wells, Kenneth B; Zaslavsky, Alan M

    2006-10-01

    In a recent report, the Institute of Medicine (IOM) defines a health service disparity between population groups to be the difference in treatment or access not justified by the differences in health status or preferences of the groups. This paper proposes an implementation of this definition, and applies it to disparities in outpatient mental health care. Health Care for Communities (HCC) reinterviewed 9,585 respondents from the Community Tracking Study in 1997-1998, oversampling individuals with psychological distress, alcohol abuse, drug abuse, or mental health treatment. The HCC is designed to make national estimates of service use. Expenditures are modeled using generalized linear models with a log link for quantity and a probit model for any utilization. We adjust for group differences in health status by transforming the entire distribution of health status for minority populations to approximate the white distribution. We compare disparities according to the IOM definition to other methods commonly used to assess health services disparities. Our method finds significant service disparities between whites and both blacks and Latinos. Estimated disparities from this method exceed those for competing approaches, because of the inclusion of effects of mediating factors (such as income) in the IOM approach. A rigorous definition of disparities is needed to monitor progress against disparities and to compare their magnitude across studies. With such a definition, disparities can be estimated by adjusting for group differences in models for expenditures and access to mental health services.

  14. Developing a Digital Medicine System in Psychiatry: Ingestion Detection Rate and Latency Period.

    Science.gov (United States)

    Profit, Deborah; Rohatagi, Shashank; Zhao, Cathy; Hatch, Ainslie; Docherty, John P; Peters-Strickland, Timothy S

    2016-09-01

    A digital medicine system (DMS) has been developed to measure and report adherence to an atypical antipsychotic, aripiprazole, in psychiatric patients. The DMS consists of 3 components: ingestible sensor embedded in a medication tablet, wearable sensor, and secure mobile and cloud-based applications. An umbrella study protocol was designed to rapidly assess the technical performance and safety of the DMS in multiple substudies to guide the technology development. Two sequential substudies enrolled 30 and 29 healthy volunteers between March-April 2014 and February-March 2015, respectively, to assess detection accuracy of the ingestible sensor by the DMS and the latency period between ingestion and detection of the ingestion by the wearable sensor or the cloud-based server. The first substudy identified areas for improvement using early versions of the wearable sensor and the mobile application. The second substudy tested updated versions of the components and showed an overall ingestion detection rate of 96.6%. Mean latency times for the signal transmission were 1.1-1.3 minutes (from ingestion to the wearable sensor detection) and 6.2-10.3 minutes (from the wearable sensor detection to the server detection). Half of transmissions were completed in < 2 minutes, and ~90% of ingestions were registered by the smartphone within 30 minutes of ingestion. No serious adverse events, discontinuations, or clinically significant laboratory/vital signs findings were reported. The DMS implementing modified versions of the smartphone application and the wearable sensor has the technical capability to detect and report tablet ingestion with high accuracy and acceptable latency time. ClinicalTrials.gov identifier: NCT02091882. © Copyright 2016 Physicians Postgraduate Press, Inc.

  15. Clinical cultural competency and knowledge of health disparities among pharmacy students.

    Science.gov (United States)

    Okoro, Olihe N; Odedina, Folakemi T; Reams, Romonia R; Smith, W Thomas

    2012-04-10

    To evaluate the level of competency and knowledge about health disparities among third-year doctor of pharmacy (PharmD) students at 2 Florida public colleges of pharmacy and to explore the demographic correlates of these variables. A cross-sectional survey study design was used to collect data from participants. The students had low health-disparities knowledge and moderate skills in dealing with sociocultural issues and cross-cultural encounters. Speaking a language(s) other than English and having exposure to cultural-competency instruction were the demographic variables found to be most significantly associated with clinical cultural competency and/or knowledge of health disparities. Clinical cultural competency and health-disparities instruction may not be adequately incorporated into the pharmacy school curricula in the institutions studied. Relevant education and training are necessary to enhance cultural competency among pharmacy students.

  16. Area-socioeconomic disparities in mental health service use among children involved in the child welfare system.

    Science.gov (United States)

    Kim, Minseop; Garcia, Antonio R; Yang, Shuyan; Jung, Nahri

    2018-06-01

    Relying on data from a nationally representative sample of youth involved in the child welfare system (CWS) in 1999-2000 (the National Survey of Child and Adolescent Well-Being, Cohort 1) and 2008-2009 (Cohort 2), this study implemented a diverse set of disparity indicators to estimate area-socioeconomic disparities in mental health (MH) services use and changes in area-socioeconomic disparities between the two cohorts. Our study found that there are area-socioeconomic disparities in MH service use, indicating that the rates of MH service use among youth referred to the CWS differ by area-socioeconomic positions defined by county-level poverty rates. We also found that area-socioeconomic disparities increased over time. However, the magnitude of the increase varied widely across disparity measures, suggesting that there are different conclusions about the trend and magnitude of area-socioeconomic disparities, depending upon which disparity measures are implemented. A greater understanding of the methodological differences among disparity measures is warranted, which will in turn impact how interventions are designed to reduce socioeconomic disparities among children in the CWS. Copyright © 2018. Published by Elsevier Ltd.

  17. Low-latency video transmission over high-speed WPANs based on low-power video compression

    DEFF Research Database (Denmark)

    Belyaev, Evgeny; Turlikov, Andrey; Ukhanova, Ann

    2010-01-01

    This paper presents latency-constrained video transmission over high-speed wireless personal area networks (WPANs). Low-power video compression is proposed as an alternative to uncompressed video transmission. A video source rate control based on MINMAX quality criteria is introduced. Practical...

  18. SUN2 Modulates HIV-1 Infection and Latency through Association with Lamin A/C To Maintain the Repressive Chromatin.

    Science.gov (United States)

    Sun, Wei-Wei; Jiao, Shi; Sun, Li; Zhou, Zhaocai; Jin, Xia; Wang, Jian-Hua

    2018-05-01

    The postintegrational latency of HIV-1 is characterized by reversible silencing of long terminal repeat (LTR)-driven transcription of the HIV genome. It is known that the formation of repressive chromatin at the 5'-LTR of HIV-1 proviral DNA impedes viral transcription by blocking the recruitment of positive transcription factors. How the repressive chromatin is formed and modulated during HIV-1 infection remains elusive. Elucidation of which chromatin reassembly factor mediates the reorganization of chromatin is likely to facilitate the understanding of the host's modulation of HIV-1 transcription and latency. Here we revealed that "Sad1 and UNC84 domain containing 2" (SUN2), an inner nuclear membrane protein, maintained the repressive chromatin and inhibited HIV LTR-driven transcription of proviral DNA through an association with lamin A/C. Specifically, lamin A/C tethered SUN2 to the nucleosomes 1 and 2 of the HIV-1 5'-LTR to block the initiation and elongation of HIV-1 transcription. SUN2 knockdown converted chromatin to an active form and thus enhanced the phosphorylation of RNA polymerase II and its recruitment to the 5'-LTR HIV-1 proviral DNA, leading to reactivation of HIV-1 from latency. Conversely, the exogenous factors such as tumor necrosis factor alpha (TNF-α) induced reactivation, and the replication of HIV-1 led to the disassociation between SUN2 and lamin A/C, suggesting that disruption of the association between SUN2 and lamin A/C to convert the repressive chromatin to the active form might be a prerequisite for the initiation of HIV-1 transcription and replication. Together, our findings indicate that SUN2 is a novel chromatin reassembly factor that helps to maintain chromatin in a repressive state and consequently inhibits HIV-1 transcription. IMPORTANCE Despite the successful use of scores of antiretroviral drugs, HIV latency poses a major impediment to virus eradication. Elucidation of the mechanism of latency facilitates the discovery of new

  19. Short-term cortical plasticity induced by conditioning pain modulation

    DEFF Research Database (Denmark)

    Egsgaard, Line Lindhardt; Buchgreitz, Line; Wang, Li

    2012-01-01

    To investigate the effects of homotopic and heterotopic conditioning pain modulation (CPM) on short-term cortical plasticity. Glutamate (tonic pain) or isotonic saline (sham) was injected in the upper trapezius (homotopic) and in the thenar (heterotopic) muscles. Intramuscular electrical stimulat......To investigate the effects of homotopic and heterotopic conditioning pain modulation (CPM) on short-term cortical plasticity. Glutamate (tonic pain) or isotonic saline (sham) was injected in the upper trapezius (homotopic) and in the thenar (heterotopic) muscles. Intramuscular electrical......, and after homotopic and heterotopic CPM versus control. Peak latencies at N100, P200, and P300 were extracted and the location/strength of corresponding dipole current sources and multiple dipoles were estimated. Homotopic CPM caused hypoalgesia (P = 0.032, 30.6% compared to baseline) to electrical...... stimulation. No cortical changes were found for homotopic CPM. A positive correlation at P200 between electrical pain threshold after tonic pain and the z coordinate after tonic pain (P = 0.032) was found for homotopic CPM. For heterotopic CPM, no significant hypoalgesia was found and a dipole shift of the P...

  20. Disparities in Intratumoral Steroidogenesis

    Science.gov (United States)

    2017-12-01

    cancer. The reasons for this racial disparity in prostate cancer incidence and mortality are unknown but may stem from economic , social, psychological...them are elevated in the prostate tumors of African American men. We further hypothesize that elevated cholesterol, which is an essential component of...cancer promotional effects of high cholesterol. Essentially , we anticipate the level of cholesterol reduction needed to protect the prostate will be

  1. Configurable Crossbar Switch for Deterministic, Low-latency Inter-blade Communications in a MicroTCA Platform

    Energy Technology Data Exchange (ETDEWEB)

    Karamooz, Saeed [Vadatech Inc. (United States); Breeding, John Eric [Oak Ridge National Lab. (ORNL), Oak Ridge, TN (United States); Justice, T Alan [Oak Ridge National Lab. (ORNL), Oak Ridge, TN (United States)

    2017-08-01

    As MicroTCA expands into applications beyond the telecommunications industry from which it originated, it faces new challenges in the area of inter-blade communications. The ability to achieve deterministic, low-latency communications between blades is critical to realizing a scalable architecture. In the past, legacy bus architectures accomplished inter-blade communications using dedicated parallel buses across the backplane. Because of limited fabric resources on its backplane, MicroTCA uses the carrier hub (MCH) for this purpose. Unfortunately, MCH products from commercial vendors are limited to standard bus protocols such as PCI Express, Serial Rapid IO and 10/40GbE. While these protocols have exceptional throughput capability, they are neither deterministic nor necessarily low-latency. To overcome this limitation, an MCH has been developed based on the Xilinx Virtex-7 690T FPGA. This MCH provides the system architect/developer complete flexibility in both the interface protocol and routing of information between blades. In this paper, we present the application of this configurable MCH concept to the Machine Protection System under development for the Spallation Neutron Sources's proton accelerator. Specifically, we demonstrate the use of the configurable MCH as a 12x4-lane crossbar switch using the Aurora protocol to achieve a deterministic, low-latency data link. In this configuration, the crossbar has an aggregate bandwidth of 48 GB/s.

  2. The terminal latency of the phrenic nerve correlates with respiratory symptoms in amyotrophic lateral sclerosis.

    Science.gov (United States)

    Park, Jin-Sung; Park, Donghwi

    2017-09-01

    The aim of the study was to investigate the electrophysiological parameters in phrenic nerve conduction studies (NCS) that sensitively reflect latent respiratory insufficiency present in amyotrophic lateral sclerosis (ALS). Forty-nine patients with ALS were examined, and after exclusion, 21 patients with ALS and their phrenic NCS results were reviewed. The patients were divided into two groups according to their respiratory sub-score in the ALS functional rating scale - revised (Group A, sub-score 12vs. Group B, sub-score 11). We compared the parameters of phrenic NCS between the two groups. There were no significant differences in the clinical characteristics between the two groups. Using a multivariate model, we found that the terminal latency of the phrenic nerve was the only parameter that was associated with early symptoms of respiratory insufficiency (pphrenic nerve was 7.65ms (sensitivity 80%, specificity 68.2%). The significantly prolonged terminal latency of the phrenic nerve in our study may reflect a profound distal motor axonal dysfunction of the phrenic nerve in patients with ALS in the early stage of respiratory insufficiency that can be used as a sensitive electrophysiological marker reflecting respiratory symptoms in ALS. The terminal latency of the phrenic nerve is useful for early detection of respiratory insufficiency in patients with ALS. Copyright © 2017. Published by Elsevier B.V.

  3. IL-15 STIMULATED NATURAL KILLER CELLS CLEAR HIV-1 INFECTED CELLS FOLLOWING LATENCY REVERSAL EX VIVO.

    Science.gov (United States)

    Garrido, Carolina; Abad-Fernandez, Maria; Tuyishime, Marina; Pollara, Justin J; Ferrari, Guido; Soriano-Sarabia, Natalia; Margolis, David M

    2018-03-28

    Current efforts towards HIV eradication include approaches to augment immune recognition and elimination of persistently infected cells following latency reversal. Natural killer (NK) cells, the main effectors of the innate immune system, recognize and clear targets using different mechanisms than CD8 + T cells, offering an alternative or complementary approach for HIV clearance strategies. We assessed the impact of IL-15 treatment on NK cell function and the potential of stimulated NK cells to clear the HIV reservoir. We measured NK cell receptor expression, antibody-dependent cell-dependent cytotoxicity (ADCC), cytotoxicity, IFN-γ production and antiviral activity in autologous HIV replication systems. All NK cell functions were uniformly improved by IL-15, and more importantly, IL-15-treated NK cells were able to clear latently HIV infected cells after exposure to vorinostat, a clinically relevant latency reversing agent. We also demonstrate that NK cells from HIV infected individuals aviremic on antiretroviral therapy can be efficiently stimulated with IL-15. Our work opens a promising line of investigation towards future immunotherapies to clear persistent HIV infection using NK cells. IMPORTANCE In the search for an HIV cure, strategies to enhance immune function to allow recognition and clearance of HIV infected cells following latency reversal are being evaluated. Natural killer (NK) cells possess characteristics that can be exploited for immunotherapy against persistent HIV infection. We demonstrate that NK cells from HIV-positive donors can be strongly stimulated with IL-15, improving their antiviral and cytotoxic potential, and more importantly, clearing HIV infected cells after latency reversal with a clinically relevant drug. Our results encourage further investigation to design NK cell-based immunotherapies to achieve HIV eradication. Copyright © 2018 American Society for Microbiology.

  4. Gender-Based Pay Disparities in Intercollegiate Coaching: The Legal Issues.

    Science.gov (United States)

    Gaal, John; Glazier, Michael S.; Evans, Thomas S.

    2002-01-01

    Explores the legal issues surrounding pay disparities between men and women in intercollegiate coaching, including how courts have treated disparate wage claims under the Equal Pay Act, Title VII of the Civil Rights Act of 1964, and Title IX, and the defenses used by institutions. Offers suggestions for defending claims and a detailed review of…

  5. Behavior of VNC in high-latency environments and techniques for improvement

    OpenAIRE

    Tan-atichat, Taurin Pete

    2008-01-01

    Thin-client computing offers many advantages over traditional PC computing including lower costs, ubiquitous access to resources, higher security, and easier maintenance. Unfortunately thin clients rely upon the services of other networked computers to properly function. Because of this tight-knit relationship, high- latency environments can render thin clients practically unusable. With the VNC thin-client system, performance can be capped at 1 frame per round-trip time (RTT) due to its clie...

  6. Data Delivery Latency Improvements And First Steps Towards The Distributed Computing Of The Caltech/USGS Southern California Seismic Network Earthquake Early Warning System

    Science.gov (United States)

    Stubailo, I.; Watkins, M.; Devora, A.; Bhadha, R. J.; Hauksson, E.; Thomas, V. I.

    2016-12-01

    The USGS/Caltech Southern California Seismic Network (SCSN) is a modern digital ground motion seismic network. It develops and maintains Earthquake Early Warning (EEW) data collection and delivery systems in southern California as well as real-time EEW algorithms. Recently, Behr et al., SRL, 2016 analyzed data from several regional seismic networks deployed around the globe. They showed that the SCSN was the network with the smallest data communication delays or latency. Since then, we have reduced further the telemetry delays for many of the 330 current sites. The latency has been reduced on average from 2-6 sec to 0.4 seconds by tuning the datalogger parameters and/or deploying software upgrades. Recognizing the latency data as one of the crucial parameters in EEW, we have started archiving the per-packet latencies in mseed format for all the participating sites in a similar way it is traditionally done for the seismic waveform data. The archived latency values enable us to understand and document long-term changes in performance of the telemetry links. We can also retroactively investigate how latent the waveform data were during a specific event or during a specific time period. In addition the near-real time latency values are useful for monitoring and displaying the real-time station latency, in particular to compare different telemetry technologies. A future step to reduce the latency is to deploy the algorithms on the dataloggers at the seismic stations and transmit either the final solutions or intermediate parameters to a central processing center. To implement this approach, we are developing a stand-alone version of the OnSite algorithm to run on the dataloggers in the field. This will increase the resiliency of the SCSN to potential telemetry restrictions in the immediate aftermath of a large earthquake, either by allowing local alarming by the single station, or permitting transmission of lightweight parametric information rather than continuous

  7. Same-Sex and Race-Based Disparities in Statutory Rape Arrests.

    Science.gov (United States)

    Chaffin, Mark; Chenoweth, Stephanie; Letourneau, Elizabeth J

    2016-01-01

    This study tests a liberation hypothesis for statutory rape incidents, specifically that there may be same-sex and race/ethnicity arrest disparities among statutory rape incidents and that these will be greater among statutory rape than among forcible sex crime incidents. 26,726 reported incidents of statutory rape as defined under state statutes and 96,474 forcible sex crime incidents were extracted from National Incident-Based Reporting System data sets. Arrest outcomes were tested using multilevel modeling. Same-sex statutory rape pairings were rare but had much higher arrest odds. A victim-offender romantic relationship amplified arrest odds for same-sex pairings, but damped arrest odds for male-on-female pairings. Same-sex disparities were larger among statutory than among forcible incidents. Female-on-male incidents had uniformly lower arrest odds. Race/ethnicity effects were smaller than gender effects and more complexly patterned. The findings support the liberation hypothesis for same-sex statutory rape arrest disparities, particularly among same-sex romantic pairings. Support for race/ethnicity-based arrest disparities was limited and mixed. © The Author(s) 2014.

  8. MK-801 and memantine act differently on short-term memory tested with different time-intervals in the Morris water maze test.

    Science.gov (United States)

    Duda, Weronika; Wesierska, Malgorzata; Ostaszewski, Pawel; Vales, Karel; Nekovarova, Tereza; Stuchlik, Ales

    2016-09-15

    N-methyl-d-aspartate receptors (NMDARs) play a crucial role in spatial memory formation. In neuropharmacological studies their functioning strongly depends on testing conditions and the dosage of NMDAR antagonists. The aim of this study was to assess the immediate effects of NMDAR block by (+)MK-801 or memantine on short-term allothetic memory. Memory was tested in a working memory version of the Morris water maze test. In our version of the test, rats underwent one day of training with 8 trials, and then three experimental days when rats were injected intraperitoneally with low- 5 (MeL), high - 20 (MeH) mg/kg memantine, 0.1mg/kg MK-801 or 1ml/kg saline (SAL) 30min before testing, for three consecutive days. On each experimental day there was just one acquisition and one test trial, with an inter-trial interval of 5 or 15min. During training the hidden platform was relocated after each trial and during the experiment after each day. The follow-up effect was assessed on day 9. Intact rats improved their spatial memory across the one training day. With a 5min interval MeH rats had longer latency then all rats during retrieval. With a 15min interval the MeH rats presented worse working memory measured as retrieval minus acquisition trial for path than SAL and MeL and for latency than MeL rats. MK-801 rats had longer latency than SAL during retrieval. Thus, the high dose of memantine, contrary to low dose of MK-801 disrupts short-term memory independent on the time interval between acquisition and retrieval. This shows that short-term memory tested in a working memory version of water maze is sensitive to several parameters: i.e., NMDA receptor antagonist type, dosage and the time interval between learning and testing. Copyright © 2016. Published by Elsevier B.V.

  9. The Biology of Cancer Health Disparities

    Science.gov (United States)

    These examples show how biology contributes to health disparities (differences in disease incidence and outcomes among distinct racial and ethnic groups, ), and how biological factors interact with other relevant factors, such as diet and the environment.

  10. When does power disparity help or hurt group performance?

    Science.gov (United States)

    Tarakci, Murat; Greer, Lindred L; Groenen, Patrick J F

    2016-03-01

    Power differences are ubiquitous in social settings. However, the question of whether groups with higher or lower power disparity achieve better performance has thus far received conflicting answers. To address this issue, we identify 3 underlying assumptions in the literature that may have led to these divergent findings, including a myopic focus on static hierarchies, an assumption that those at the top of hierarchies are competent at group tasks, and an assumption that equality is not possible. We employ a multimethod set of studies to examine these assumptions and to understand when power disparity will help or harm group performance. First, our agent-based simulation analyses show that by unpacking these common implicit assumptions in power research, we can explain earlier disparate findings--power disparity benefits group performance when it is dynamically aligned with the power holder's task competence, and harms group performance when held constant and/or is not aligned with task competence. Second, our empirical findings in both a field study of fraud investigation groups and a multiround laboratory study corroborate the simulation results. We thereby contribute to research on power by highlighting a dynamic understanding of power in groups and explaining how current implicit assumptions may lead to opposing findings. (c) 2016 APA, all rights reserved).

  11. Reduced complexity and latency for a massive MIMO system using a parallel detection algorithm

    Directory of Open Access Journals (Sweden)

    Shoichi Higuchi

    2017-09-01

    Full Text Available In recent years, massive MIMO systems have been widely researched to realize high-speed data transmission. Since massive MIMO systems use a large number of antennas, these systems require huge complexity to detect the signal. In this paper, we propose a novel detection method for massive MIMO using parallel detection with maximum likelihood detection with QR decomposition and M-algorithm (QRM-MLD to reduce the complexity and latency. The proposed scheme obtains an R matrix after permutation of an H matrix and QR decomposition. The R matrix is also eliminated using a Gauss–Jordan elimination method. By using a modified R matrix, the proposed method can detect the transmitted signal using parallel detection. From the simulation results, the proposed scheme can achieve a reduced complexity and latency with a little degradation of the bit error rate (BER performance compared with the conventional method.

  12. Treatment of high-latency microcapsules containing an aluminium complex with an epoxy-functionalised trialkoxysilane.

    Science.gov (United States)

    Kamiya, Kazunobu; Suzuki, Noboru

    2016-12-01

    Some aluminium complexes are excellent catalysts of cationic polymerisation and are used for low-temperature and fast-curing adhesive, used in electronic part mounting. Microencapsulation is a suitable technique for getting high latency of the catalysts and long shelf life of the adhesives. For the higher latency in a cycloaliphatic epoxy compound, the microcapsule surface which retained small amount of aluminium complex was coated with epoxy polymer and the effect was examined. From the X-ray photoelectron spectroscopic results, the surface was recognised to be sufficiently coated and the differential scanning calorimetric analyses showed that the coating did not significantly affect the low-temperature and fast-curing properties of adhesive. After storing the mixture of cycloaliphatic epoxy compound, coated microcapsules, triphenylsilanol and silane coupling agent for 48 h at room temperature, the increase in viscosity was only 0.01 Pa s, resulting in the excellent shelf life.

  13. Design and performance of a high resolution, low latency stripline beam position monitor system

    Science.gov (United States)

    Apsimon, R. J.; Bett, D. R.; Blaskovic Kraljevic, N.; Burrows, P. N.; Christian, G. B.; Clarke, C. I.; Constance, B. D.; Dabiri Khah, H.; Davis, M. R.; Perry, C.; Resta López, J.; Swinson, C. J.

    2015-03-01

    A high-resolution, low-latency beam position monitor (BPM) system has been developed for use in particle accelerators and beam lines that operate with trains of particle bunches with bunch separations as low as several tens of nanoseconds, such as future linear electron-positron colliders and free-electron lasers. The system was tested with electron beams in the extraction line of the Accelerator Test Facility at the High Energy Accelerator Research Organization (KEK) in Japan. It consists of three stripline BPMs instrumented with analogue signal-processing electronics and a custom digitizer for logging the data. The design of the analogue processor units is presented in detail, along with measurements of the system performance. The processor latency is 15.6 ±0.1 ns . A single-pass beam position resolution of 291 ±10 nm has been achieved, using a beam with a bunch charge of approximately 1 nC.

  14. Latency-Associated Expression of Human Cytomegalovirus US28 Attenuates Cell Signaling Pathways To Maintain Latent Infection

    Directory of Open Access Journals (Sweden)

    Benjamin A. Krishna

    2017-12-01

    Full Text Available Reactivation of human cytomegalovirus (HCMV latent infection from early myeloid lineage cells constitutes a threat to immunocompromised or immune-suppressed individuals. Consequently, understanding the control of latency and reactivation to allow targeting and killing of latently infected cells could have far-reaching clinical benefits. US28 is one of the few viral genes that is expressed during latency and encodes a cell surface G protein-coupled receptor (GPCR, which, during lytic infection, is a constitutive cell-signaling activator. Here we now show that in monocytes, which are recognized sites of HCMV latency in vivo, US28 attenuates multiple cell signaling pathways, including mitogen-activated protein (MAP kinase and NF-κB, and that this is required to establish a latent infection; viruses deleted for US28 initiate a lytic infection in infected monocytes. We also show that these monocytes then become potent targets for the HCMV-specific host immune response and that latently infected cells treated with an inverse agonist of US28 also reactivate lytic infection and similarly become immune targets. Consequently, we suggest that the use of inhibitors of US28 could be a novel immunotherapeutic strategy to reactivate the latent viral reservoir, allowing it to be targeted by preexisting HCMV-specific T cells.

  15. Effects of Social, Economic, and Labor Policies on Occupational Health Disparities

    Science.gov (United States)

    Siqueira, Carlos Eduardo; Gaydos, Megan; Monforton, Celeste; Slatin, Craig; Borkowski, Liz; Dooley, Peter; Liebman, Amy; Rosenberg, Erica; Shor, Glenn; Keifer, Matthew

    2018-01-01

    Background This article introduces some key labor, economic, and social policies that historically and currently impact occupational health disparities in the United States. Methods We conducted a broad review of the peer-reviewed and gray literature on the effects of social, economic, and labor policies on occupational health disparities. Results Many populations such as tipped workers, public employees, immigrant workers, and misclassified workers are not protected by current laws and policies, including worker’s compensation or Occupational Safety and Health Administration enforcement of standards. Local and state initiatives, such as living wage laws and community benefit agreements, as well as multiagency law enforcement contribute to reducing occupational health disparities. Conclusions There is a need to build coalitions and collaborations to command the resources necessary to identify, and then reduce and eliminate occupational disparities by establishing healthy, safe, and just work for all. PMID:23606055

  16. 76 FR 18566 - National Center on Minority and Health Disparities; Notice of Closed Meeting

    Science.gov (United States)

    2011-04-04

    ... and Health Disparities; Notice of Closed Meeting Pursuant to section 10(d) of the Federal Advisory... and Health Disparities Special Emphasis Panel, NIMHD Conference Grant Application (R13) Review. Date... Health and Health Disparities, 6707 Democracy Boulevard, Suite 800, Bethesda, MD 20892, (301) 451-9536...

  17. Shift of the Muscular Inhibition Latency during On-Line Acquisition of Anticipatory Postural Adjustments.

    Directory of Open Access Journals (Sweden)

    Fanny Barlaam

    Full Text Available During action, Anticipatory Postural Adjustments (APAs cancel the consequences of a movement on postural stabilization. Their muscular expression is characterized by early changes in the activity of the postural muscles, before the movement begins. To explore the mechanisms enabling the acquisition of APAs, a learning paradigm was designed in which the voluntary lifting of a load with one hand triggered the unloading of another load suspended below the contralateral forearm. The aim of this study was to investigate changes in the muscular expression that uncovers the progressive learning of new APAs. A trial-by-trial analysis of kinematic and electromyographic signals recorded on the right arm was conducted in twelve adults through six sessions of learning. Kinematic results reported an enhancement of the postural stabilization across learning. The main EMG pattern found during learning consisted of a flexor inhibition, where latency was shifted towards an earlier occurrence in parallel with the improvement of the postural performance. A linear regression analysis conducted between the inhibition latency and the maximal amplitude of elbow rotation showed that the earlier the inhibition onset, the better the postural stabilization. This study revealed that the progressive shift of the postural flexor inhibition latency could be considered as a reliable neurophysiological marker of the progressive learning of new APAs. Importantly, this marker could be used to track motor learning abnormalities in pathology. We relate our findings to the update of a forward predictive model of action, defined as a system that predicts beforehand the consequences of the action on posture.

  18. A new therapeutic strategy for lengthening severe short nose.

    Science.gov (United States)

    Rikimaru, Hideaki; Kiyokawa, Kensuke; Watanabe, Koichi; Koga, Noriyuki; Nishi, Yukiko

    2010-03-01

    Correction of severe short nose is a distressing problem for plastic surgeons. It is difficult to simultaneously lengthen the 3 components of the nose, which are the outer skin envelope, the framework, and the mucosal lining. We developed a new method to lengthen the nose more than 10 mm definitively and safely, which was performed using the technique of distraction osteogenesis. The procedure involves a 2-stage operation. At the first stage, boat-shaped iliac bone is grafted on the dorsum. More than 6 months later, the second-stage operation is performed. The grafted bone is cut horizontally in the center, and the distraction device is applied to it. Distraction osteogenesis is started after a latency period of 14 days and performed at a rate of 0.6 mm once daily. The distraction device is replaced by a special attachment (Ribbond; Ribbond Inc) during the 3-month consolidation period. Our method was applied for 2 patients with congenitally and posttraumatic severe short nose, respectively. The total amount of distraction osteogenesis was 12.6 and 13.8 mm, respectively. The profiles of both of the patients improved, and they were satisfied with the results. The method we developed is an entirely new approach to the correction of severe short nose. Furthermore, it was determined that nonvascularized grafted iliac bone could be lengthened by distraction osteogenesis. Our new method was a very effective and definitive technique and could become a mainstream procedure for the correction of severe short nose.

  19. Disparities in sexually transmitted disease rates across the "eight Americas".

    Science.gov (United States)

    Chesson, Harrell W; Kent, Charlotte K; Owusu-Edusei, Kwame; Leichliter, Jami S; Aral, Sevgi O

    2012-06-01

    The purpose of this study was to examine rates of 3 bacterial sexually transmitted diseases (STDs; syphilis, gonorrhea, and chlamydia) in 8 subpopulations (known as the "eight Americas") defined by race and a small number of county-level sociodemographic and geographical characteristics. The eight Americas are (1) Asians and Pacific Islanders in specific counties; (2) Northland low-income rural white; (3) Middle America; (4) Low-income whites in Appalachia and Mississippi Valley; (5) Western Native American; (6) Black middle America; (7) Southern low-income rural black; and (8) High-risk urban black. A list of the counties comprising each of the eight Americas was obtained from the corresponding author of the original eight Americas project, which examined disparities in mortality rates across the eight Americas. Using county-level STD surveillance data, we calculated syphilis, gonorrhea, and chlamydia rates (new cases per 100,000) for each of the eight Americas. Reported STD rates varied substantially across the eight Americas. STD rates were generally lowest in Americas 1 and 2 and highest in Americas 6, 7, and 8. Although disparities in STDs across the eight Americas are generally similar to the well-established disparities in STDs across race/ethnicity, the grouping of counties into the eight Americas does offer additional insight into disparities in STDs in the United States. The high STD rates we found for black Middle America are consistent with the assertion that sexual networks and social factors are important drivers of racial disparities in STDs.

  20. Examining Sexual Orientation Disparities in Unmet Medical Needs among Men and Women.

    Science.gov (United States)

    Everett, Bethany G; Mollborn, Stefanie

    2014-08-01

    Using the National Longitudinal Study of Adolescent Health (N = 13,810), this study examines disparities in unmet medical needs by sexual orientation identity during young adulthood. We use binary logistic regression and expand Andersen's health care utilization framework to identify factors that shape disparities in unmet medical needs by sexual orientation. We also investigate whether the well-established gender disparity in health-seeking behaviors among heterosexual persons holds for sexual minorities. The results show that sexual minority women are more likely to report unmet medical needs than heterosexual women, but no differences are found between sexual minority and heterosexual men. Moreover, we find a reversal in the gender disparity between heterosexual and sexual minority populations: heterosexual women are less likely to report unmet medical needs than heterosexual men, whereas sexual minority women are more likely to report unmet medical needs compared to sexual minority men. Finally, this work advances Andersen's model by articulating the importance of including social psychological factors for reducing disparities in unmet medical needs by sexual orientation for women.