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Sample records for eye studies hartley

  1. CN Morphology Studies of Comet 103P/Hartley 2

    CERN Document Server

    Knight, Matthew M

    2011-01-01

    We report on narrowband CN imaging of Comet 103P/Hartley 2 obtained at Lowell Observatory on 39 nights from 2010 July until 2011 January. We observed two features, one generally to the north and the other generally to the south. The CN morphology varied during the apparition: no morphology was seen in July; in August and September the northern feature dominated and appeared as a mostly face-on spiral; in October, November, and December the northern and southern features were roughly equal in brightness and looked like more side-on corkscrews; in January the southern feature was dominant but the morphology was indistinct due to very low signal. The morphology changed smoothly during each night and similar morphology was seen from night to night. However, the morphology did not exactly repeat each rotation cycle, suggesting that there is a small non-principal axis rotation. Based on the repetition of the morphology, we find evidence that the fundamental rotation period was increasing: 16.7 hr from August 13-17,...

  2. Hartley transform and the use of the Whitened Hartley spectrum as a tool for phase spectral processing

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    Ioannis Paraskevas

    2015-03-01

    Full Text Available The Hartley transform is a mathematical transformation which is closely related to the better known Fourier transform. The properties that differentiate the Hartley Transform from its Fourier counterpart are that the forward and the inverse transforms are identical and also that the Hartley transform of a real signal is a real function of frequency. The Whitened Hartley spectrum, which stems from the Hartley transform, is a bounded function that encapsulates the phase content of a signal. The Whitened Hartley spectrum, unlike the Fourier phase spectrum, is a function that does not suffer from discontinuities or wrapping ambiguities. An overview on how the Whitened Hartley spectrum encapsulates the phase content of a signal more efficiently compared with its Fourier counterpart as well as the reason that phase unwrapping is not necessary for the Whitened Hartley spectrum, are provided in this study. Moreover, in this study, the product–convolution relationship, the time-shift property and the power spectral density function of the Hartley transform are presented. Finally, a short-time analysis of the Whitened Hartley spectrum as well as the considerations related to the estimation of the phase spectral content of a signal via the Hartley transform, are elaborated.

  3. Danish Rural Eye Study

    DEFF Research Database (Denmark)

    Høeg, Tracy B; Moldow, Birgitte; Ellervik, Christina

    2015-01-01

    PURPOSE: To determine the prevalence of amblyopia in Denmark before and after the initiation of the Danish national preschool vision screening programme. METHODS: In a population-based cross-sectional study, 3826 participants of the Danish General Suburban Population Study (GESUS) aged 20 years...... 45-degree retinal fundus photographs of each eye. A complete ophthalmologic examination was performed when indicated. RESULTS: The prevalence of monocular visual impairment (MVI) was 4.26% (95% CI, 3.66-4.95, n = 163). Amblyopia was the most common cause, accounting for 33%. The prevalence...... of amblyopia was 1.44% (95% CI, 1.01-1.81, n = 55), being higher among non-preschool vision screened persons compared to those who were offered (estimated 95% attendance) preschool vision screening (1.78%, n = 41, 95% CI 1.24-2.33 versus 0.44%, n = 2, 95% CI, 0.12-1.60, p = 0.024). The leading cause...

  4. Tromsø eye study

    DEFF Research Database (Denmark)

    Bertelsen, Geir; Peto, Tunde; Lindekleiv, Haakon;

    2013-01-01

    Purpose:  To determine the prevalence of visual impairment, retinopathy and macular oedema, and assess risk factors for retinopathy in persons with diabetes. Methods:  The present study included 514 participants with diabetes aged 46-87 years from the Tromsø Eye Study, a sub-study of the population......-based Tromsø Study in Norway. Visual acuity was measured using an auto-refractor. Retinal images from both eyes were graded for retinopathy and macular oedema. We collected data on risk factor exposure from self-report questionnaires, clinical examinations, laboratory measurements and case note reviews....... Regression models assessed the cross-sectional relationship between potential risk factors and diabetic retinopathy. Results:  The prevalence of visual impairment (corrected Snellen visual acuity...

  5. Cartilage Degeneration, Subchondral Mineral and Meniscal Mineral Densities in Hartley and Strain 13 Guinea Pigs.

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    Sun, Yubo; Scannell, Brian P; Honeycutt, Patrick R; Mauerhan, David R; H, James Norton; Hanley, Edward N

    2015-01-01

    Osteoarthritis is a joint disease involved in articular cartilage, subchondral bone, meniscus and synovial membrane. This study sought to examine cartilage degeneration, subchondral bone mineral density (BMD) and meniscal mineral density (MD) in male Hartley, female Hartley and female strain 13 guinea pigs to determine the association of cartilage degeneration with subchondral BMD and meniscal MD. Cartilage degeneration, subchondral BMD and meniscal MD in 12 months old guinea pigs were examined with histochemistry, X-ray densitometry and calcium analysis. We found that male Hartley guinea pigs had more severe cartilage degeneration, subchondral BMD and meniscal MD than female Hartley guinea pigs, but not female strain 13 guinea pigs. Female strain 13 guinea pigs had more severe cartilage degeneration and higher subchondral BMD, but not meniscal MD, than female Hartley guinea pigs. These findings indicate that higher subchondral BMD, not meniscal MD, is associated with more severe cartilage degeneration in the guinea pigs and suggest that abnormal subchondral BMD may be a therapeutic target for OA treatment. These findings also indicate that the pathogenesis of OA in the male guinea pigs and female guinea pigs are different. Female strain 13 guinea pig may be used to study female gender-specific pathogenesis of OA.

  6. The application of Hartley transform to ocean engineering

    Institute of Scientific and Technical Information of China (English)

    Hequan Sun; Dahong Qiu; Yongxue Wang

    2003-01-01

    The Hartley transform is a real integral transform based on harmonic functions and hassome characteristics similar to the Fourier transform. Most applications in ocean engineering requiringthe Fourier transform can also be performed by the Hartley transform. The fast Hartley transform istwice faster and more convenient to handle than the corresponding fast Fourier transform, so it is a realvalued alternative to the complex Fourier transform in many applications. The use of the Hartley trans-form in ocean engineering is presented in detail in this paper, including wave spectral analysis, separationof waves, cross-correlation in PIV technique and expression of equation in the Hartley domain. The ex-amples in the paper show deeply the advantage and efficiency of the Hartley transform over the Fouriertransform.

  7. The Tromsø Eye Study

    DEFF Research Database (Denmark)

    Bertelsen, Geir; Erke, Maja G; von Hanno, Therese

    2013-01-01

    Purpose:  To describe the study design and methodology of the Tromsø Eye Study (TES), and to describe visual acuity and refractive error in the study population. Methods:  The Tromsø Eye Study is a sub-study of the Tromsø Study, a population-based multipurpose longitudinal study in the municipality...... of Tromsø, Norway. The Tromsø Eye Study was a part of the sixth survey of the Tromsø Study, conducted from October 2007 through December 2008. The eye examination included information on self-reported eye diseases, assessment of visual acuity and refractive errors, retinal photography and optical coherence...... tomography. Retinal images were graded for diabetic retinopathy and age-related macular degeneration, and with computer-assisted measurements of arteriolar and venular diameters. In addition, TES researchers have access to the large comprehensive Tromsø Study database including physical examination results...

  8. The Tehran Eye Study: research design and eye examination protocol

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    Fotouhi Akbar

    2003-07-01

    Full Text Available Abstract Background Visual impairment has a profound impact on society. The majority of visually impaired people live in developing countries, and since most disorders leading to visual impairment are preventable or curable, their control is a priority in these countries. Considering the complicated epidemiology of visual impairment and the wide variety of factors involved, region specific intervention strategies are required for every community. Therefore, providing appropriate data is one of the first steps in these communities, as it is in Iran. The objectives of this study are to describe the prevalence and causes of visual impairment in the population of Tehran city; the prevalence of refractive errors, lens opacity, ocular hypertension, and color blindness in this population, and also the familial aggregation of refractive errors, lens opacity, ocular hypertension, and color blindness within the study sample. Methods Design Through a population-based, cross-sectional study, a total of 5300 Tehran citizens will be selected from 160 clusters using a stratified cluster random sampling strategy. The eligible people will be enumerated through a door-to-door household survey in the selected clusters and will be invited. All participants will be transferred to a clinic for measurements of uncorrected, best corrected and presenting visual acuity; manifest, subjective and cycloplegic refraction; color vision test; Goldmann applanation tonometry; examination of the external eye, anterior segment, media, and fundus; and an interview about demographic characteristics and history of eye diseases, eye trauma, diabetes mellitus, high blood pressure, and ophthalmologic cares. The study design and eye examination protocol are described. Conclusion We expect that findings from the TES will show the status of visual problems and their causes in the community. This study can highlight the people who should be targeted by visual impairment prevention programs.

  9. Temperature Preference in IAF Hairless and Hartley Guinea Pigs (Cavia porcellus).

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    Kleven, Gale A; Joshi, Prianca

    2016-03-01

    The Hairless strain of guinea pigs (Cavia porcellus) is the result of a spontaneous recessive mutation first identified at the Institute Armand Frappier (IAF) in 1978. Despite the longstanding availability of this strain, little is known about its thermoregulatory behavior. The aim of this study was to determine temperature preference in Hartley and Hairless guinea pigs by observing each strain in a ring-shaped apparatus containing a nonlinear temperature gradient. Temperatures were maintained by separately controlled heating mats lining the apparatus. Set point temperatures ranged from 24 to 38 °C. Guinea pigs (Hartley female, Hairless female, and Hairless male guinea pigs; n = 8 each group) were placed either singly or in pairs at 1 of the 8 randomized starting points within the apparatus. Subjects were observed for 30 min and coded for location within the temperature gradient by both frequency and duration. When placed singly in the apparatus, all 3 groups spent more time in the 30 °C zones. However, when placed as pairs with a cagemate, Hartley female guinea pigs spent more time in the cooler range of temperatures from 24 to 30 °C, whereas Hairless guinea pigs preferred a range of 30 to 38 °C. These results confirm a temperature preference of 30 ± 2 °C for both Hartley and Hairless guinea pigs when singly housed. However, data from the paired housing condition suggest that context plays an important role in thermoregulatory behavior.

  10. Viewpoint Consistency: An Eye Movement Study

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    Filipe Cristino

    2012-05-01

    Full Text Available Eye movements have been widely studied, using images and videos in laboratories or portable eye trackers in the real world. Although a good understanding of the saccadic system and extensive models of gaze have been developed over the years, only a few studies have focused on the consistency of eye movements across viewpoints. We have developed a new technique to compute and map the depth of collected eye movements on stimuli rendered from 3D mesh objects using a traditional corneal reflection eye tracker (SR Eyelink 1000. Having eye movements mapped into 3D space (and not on an image space allowed us to compare fixations across viewpoints. Fixation sequences (scanpaths were also studied across viewpoints using the ScanMatch method (Cristino et al 2010, Behavioural and Research Methods 42, 692–700, extended to work with 3D eye movements. In a set of experiments where participants were asked to perform a recognition task on either a set of objects or faces, we recorded their gaze while performing the task. Participants either viewed the stimuli in 2D or using anaglyph glasses. The stimuli were shown from different viewpoints during the learning and testing phases. A high degree of gaze consistency was found across the different viewpoints, particularly between learning and testing phases. Scanpaths were also similar across viewpoints, suggesting not only that the gazed spatial locations are alike, but also their temporal order.

  11. Zika Found in Eye Fluid in Study

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    ... page: https://medlineplus.gov/news/fullstory_160986.html Zika Found in Eye Fluid in Study Virus may ... 15, 2016 THURSDAY, Sept. 15, 2016 (HealthDay News) -- Zika can be detected in fluid inside the eyelid ...

  12. A study of artificial eyes for the measurement of precision in eye-trackers.

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    Wang, Dong; Mulvey, Fiona B; Pelz, Jeff B; Holmqvist, Kenneth

    2016-07-06

    The precision of an eye-tracker is critical to the correct identification of eye movements and their properties. To measure a system's precision, artificial eyes (AEs) are often used, to exclude eye movements influencing the measurements. A possible issue, however, is that it is virtually impossible to construct AEs with sufficient complexity to fully represent the human eye. To examine the consequences of this limitation, we tested currently used AEs from three manufacturers of eye-trackers and compared them to a more complex model, using 12 commercial eye-trackers. Because precision can be measured in various ways, we compared different metrics in the spatial domain and analyzed the power-spectral densities in the frequency domain. To assess how precision measurements compare in artificial and human eyes, we also measured precision using human recordings on the same eye-trackers. Our results show that the modified eye model presented can cope with all eye-trackers tested and acts as a promising candidate for further development of a set of AEs with varying pupil size and pupil-iris contrast. The spectral analysis of both the AE and human data revealed that human eye data have different frequencies that likely reflect the physiological characteristics of human eye movements. We also report the effects of sample selection methods for precision calculations. This study is part of the EMRA/COGAIN Eye Data Quality Standardization Project.

  13. The National Basketball Association eye injury study.

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    Zagelbaum, B M; Starkey, C; Hersh, P S; Donnenfeld, E D; Perry, H D; Jeffers, J B

    1995-06-01

    To investigate the epidemiology of eye injuries sustained by professional basketball players in the National Basketball Association (NBA). A prospective study involving all NBA athletes who sustained eye injuries between February 1, 1992, and June 20, 1993, was conducted. Twenty-seven NBA team athletic trainers, physicians, and ophthalmologists were provided data forms to complete for any player examined for an eye injury. Practice and game exposures during the preseason, regular season, playoffs, and championships were included. Of the 1092 injuries sustained by NBA players during the 17-month period, 59 (5.4%) involved the eye and adnexa. Eighteen (30.5%) of the injuries occurred while the player was in the act of rebounding, and 16 (27.1%) while the player was on offense. The most common diagnoses included 30 abrasions or lacerations to the eyelid (50.9%), 17 contusions (edema and/or ecchymosis) to the eyelid or periorbital region (28.8%), and seven corneal abrasions (11.9%). There were three orbital fractures (5.1%). Most injuries were caused by fingers (35.6%) or elbows (28.8%). Nine players (15.3%) missed subsequent games because of their injury. Fifty-seven players (96.6%) were not wearing protective eyewear at the time of injury. The incidence of eye injuries in NBA players during the 17-month period was 1.44 per 1000 game exposures. Frequent physical contact in professional basketball players leaves them at great risk for sustaining eye injuries. To prevent these injuries, protective eyewear is recommended.

  14. Post-destructive eye surgery, associated depression at Sekuru Kaguvi Hospital Eye Unit, Zimbabwe: Pilot Study

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    M. M. Kawome

    2013-12-01

    Full Text Available Destructive eye surgery is associated with more complications than just loss of visual functions of the eye and aesthetics. Currently there is very little published literature on post-destructive eye surgery associated depression. Zimbabwe has been experiencing a surge in the rate of destructive eye surgery done at the National Tertiary Eye Unit. This situation could be churning out lots of unrecognized depressed clients into the community who require assistance in one form or another.Objectives: To determine the prevalence of post-destructive eye surgery associated depression among patients attending Sekuru Kaguvi Hospital Eye Unit and assess if the current management protocol of patients undergoing destructive eye surgery at the Eye Unit addresses the problem adequately.Methods: A cross-sectional study of 28 randomly selected patients who had destructive eye surgeries at Sekuru Kaguvi Hospital was conducted over five months from 1st March 2012 to end of July 2012. A structured questionnaire containing 15 questions on the following items: gender, age, diagnosis, surgical procedure done, expectations before and after surgery, adequacy of counseling given and involvement of family was used to collect data. Nine questions to assess depression were adapted from the Patient Health Questionnaire (PHQ-9.Setting:  The study was conducted at SekuruKaguvi Hospital Eye Unit, Parirenyatwa Group of Hospitals in Harare.Results:  Twenty-eight patients who underwent destructive eye surgery during the study period were selected using systematic random sampling. The gender ratio was 1:1 and the mean age was 38.7 years with a range from 24 to 65 years. Fifty percent of the patients in the study had orbital exenteration while the rest had enucleation (14% and evisceration (36%. Twenty-eight percent of the study population had depression.Conclusion: Destructive eye surgery is frequently associated with depression and our current management protocol of patients

  15. Cohort profile: Shahroud Eye Cohort Study.

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    Fotouhi, Akbar; Hashemi, Hassan; Shariati, Mohammad; Emamian, Mohammad Hassan; Yazdani, Kamran; Jafarzadehpur, Ebrahim; Koohian, Hassan; Khademi, Mohammad Reza; Hodjatjalali, Kamran; Kheirkhah, Ahmad; Chaman, Reza; Malihi, Sarvenaz; Mirzaii, Mehdi; Khabazkhoob, Mehdi

    2013-10-01

    The Shahroud Eye Cohort Study was set up to determine the prevalence and incidence of visual impairment and major eye conditions in the 40-64-year-old population of Shahroud as a Middle Eastern population. The first phase of the study was conducted in 2009-10. Using random cluster sampling, 6311 Shahroud inhabitants were invited for ophthalmologic examinations; of these, 5190 participants completed phase 1 (participation rate of 82.2%). All participants were interviewed to collect data on participants' demographics, occupation status, socioeconomic status, history of smoking, and medical and ophthalmic history, as well as history of medication, and the quality and duration of their insurance. DNA and plasma samples, as well as four dots of whole blood were collected from participants. Extensive optometric and ophthalmologic examinations were performed for each participant, including lensometry of current glasses, testing near and far visual acuity; determining objective and subjective refraction; eye motility; cycloplegic refraction; colour vision test; slit-lamp biomicroscopy and intraocular pressure measurement; direct and indirect fundoscopy; perimetry test; ocular biometry; corneal topography; lens and fundus photography; and the Schirmer's (1008 participants) and tear breakup time tests (1013 participants). The study data are available for collaborative research at Noor Ophthalmology Research Center, Tehran, Iran.

  16. Multi-View Algorithm for Face, Eyes and Eye State Detection in Human Image- Study Paper

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    Latesh Kumari

    2014-07-01

    Full Text Available For fatigue detection such as in the application of driver‟s fatigue monitoring system, the eye state analysis is one of the important and deciding steps to determine the fatigue of driver‟s eyes. In this study, algorithms for face detection, eye detection and eye state analysis have been studied and presented as well as an efficient algorithm for detection of face, eyes have been proposed. Firstly the efficient algorithm for face detection method has been presented which find the face area in the human images. Then, novel algorithms for detection of eye region and eye state are introduced. In this paper we propose a multi-view based eye state detection to determine the state of the eye. With the help of skin color model, the algorithm detects the face regions in an YCbCr color model. By applying the skin segmentation which normally separates the skin and non-skin pixels of the images, it detects the face regions of the image under various lighting and noise conditions. Then from these face regions, the eye regions are extracted within those extracted face regions. Our proposed algorithms are fast and robust as there is not pattern match.

  17. Optical Image Encryption with Simplified Fractional Hartley Transform

    Institute of Scientific and Technical Information of China (English)

    LI Xin-Xin; ZHAO Dao-Mu

    2008-01-01

    We present a new method for image encryption on the basis of simplified fractional Hartley transform (SFRHT). SFRHT is a real transform as Hartley transform (HT) and furthermore, superior to HT in virtue of the advantage that it can also append fractional orders as additional keys for the purpose of improving the system security to some extent. With this method, one can encrypt an image with an intensity-only medium such as a photographic film or a CCD camera by spatially incoherent or coherent illumination. The optical realization is then proposed and computer simulations are also performed to verify the feasibility of this method.

  18. Eye-Tracking Study of Complexity in Gas Law Problems

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    Tang, Hui; Pienta, Norbert

    2012-01-01

    This study, part of a series investigating students' use of online tools to assess problem solving, uses eye-tracking hardware and software to explore the effect of problem difficulty and cognitive processes when students solve gas law word problems. Eye movements are indices of cognition; eye-tracking data typically include the location,…

  19. Eye-Tracking Study of Complexity in Gas Law Problems

    Science.gov (United States)

    Tang, Hui; Pienta, Norbert

    2012-01-01

    This study, part of a series investigating students' use of online tools to assess problem solving, uses eye-tracking hardware and software to explore the effect of problem difficulty and cognitive processes when students solve gas law word problems. Eye movements are indices of cognition; eye-tracking data typically include the location,…

  20. Quantitative study of spontaneous eye blinks and eye tics in Gilles de la Tourette's syndrome

    NARCIS (Netherlands)

    J.H.M. Tulen (Joke); M. Azzolini; J.A. de Vries; W.H. Groeneveld; J. Passchier (Jan); B.J.M. van de Wetering (Ben)

    1999-01-01

    textabstractSpontaneous eye blink rate and frequency of eye tics were studied in nine Tourette patients during periods of rest, conversation, and video watching. In comparison with controls, the Tourette patients showed a significantly higher blink rate during rest and

  1. Peripapillary intrachoroidal cavitations. The Beijing eye study.

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    Qi Sheng You

    Full Text Available PURPOSE: To assess prevalence, size and location of peripapillary intrachoroidal cavitations (PICCs and their associations in a population-based sample. . METHODS: The population-based Beijing Eye Study 2011 included 3468 individuals with a mean age of 64.6 ± 9.8 years (range:50-93 years. A detailed ophthalmic examination included enhanced depth imaging of the choroid by spectral-domain optical coherence tomography and fundus photography. PICCs were defined as triangular thickening of the choroid with the base at the optic disc border and a distance between Bruch's membrane and sclera of ≥ 200 μm. Parapapillary large choroidal vessels were excluded. RESULTS: Out of 94 subjects with high myopia (refractive error 26.5mm in right eyes, OCT images were available for 89 (94.7% participants. A PICC was detected in 15 out of these 89 highly myopic subjects (prevalence:16.9 ± 4.0% and in none of hyperopic, emmetropic or medium myopic subgroups each consisting of 100 randomly selected subjects. Mean PICC width was 4.2 ± 2.3 hours (30° of disc circumference and mean length was 1363 ± 384 μm. PICCs were located most frequently (40% at the inferior disc border. On fundus photos, a typical yellow-orange lesion was found in 8 (53% eyes with PICCs. In binary regression analysis, presence of PICCs was significantly associated with optic disc tilting (P=0.04 and presence of posterior staphylomata (P=0.046. CONCLUSIONS: Prevalence of PICCs in the adult Chinese population was 16.9 ± 4.0% in the highly myopic group, with no PICCs detected in non-highly myopic eyes. PICCs were located most frequently at the inferior optic disc border. Only half of the PICCs detected on OCT images showed a yellow-orange lesion on fundus photos. Presence of PICC was significantly associated only with an increased optic disc tilting and presence of posterior staphylomata, while it was not associated with axial length, refractive error or other ocular or systemic parameters.

  2. Eye dominance in children: a longitudinal study.

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    Dellatolas, G; Curt, F; Dargent-Paré, C; De Agostini, M

    1998-05-01

    In a sample of 807 normal preschool children aged from 3 to 6, examined eye dominance was not associated with the declared eye dominance of their parents. Forty percent of the children showed left-eyedness. Eyedness was associated with handedness and not significantly related to age group or sex. A strong relationship between the answers of the two parents concerning eye preference was observed. Two hundred forty-four children were followed-up for 2 years. The examinations were carried out once every 6 months. Two thirds of the children showed perfect stability in eye dominance. There was some evidence that stability in eye use tends to increase with age and to be lower in left-handed children with left-handed parents. There is, at present, very little evidence of a positive association between eye dominance in parents and that in their children.

  3. Furoquinoline Alkaloids and Methoxyflavones from the Stem Bark of Melicope madagascariensis (Baker T.G. Hartley

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    Vincent E. Rasamison

    2016-09-01

    Full Text Available Abstract Melicope madagascariensis (Rutaceae is an endemic plant species of Madagascar that was first classified as a member of the genus Euodia J. R. & G. Forst (Rutaceae under the scientific name Euodia madagascariensis Baker. Based on morphological characteristics, Thomas Gordon Hartley taxonomically revised E. madagascariensis Baker to be M. madagascariensis (Baker T.G. Hartley. Chemotaxonomical studies have long been used to help the identification and confirmation of taxonomical classification of plant species and botanicals. Aiming to find more evidences to support the taxonomical revision performed on E. madagascariensis, we carried out phytochemical investigation of two samples of the plant. Fractionation of the ethanol extracts prepared from two stem bark samples of M. madagascariensis (Baker T.G. Hartley led to the isolation of seven known furoquinoline alkaloids 1–7 and two known methoxyflavones 8 and 9. The presence of furoquinoline alkaloids and methoxyflavones in the title species is in agreement with its taxonomic transfer from Euodia to Melicope. Antiprotozoal evaluation of the isolated compounds showed that 6-methoxy-7-hydroxydictamnine (heliparvifoline, 3 showed weak antimalarial activity (IC50 = 35 µM against the chloroquine-resistant strain Dd2 of Plasmodium falciparum. Skimmianine (4 displayed moderate cytotoxicity with IC50 value of 1.5 µM against HT-29 colon cancer cell line whereas 3,5-dihydroxy-3′,4′,7-trimethoxyflavone (9 was weakly active in the same assay (IC50 = 13.9 µM. Graphical Abstract

  4. Submacular hemorrhage: A study amongst Indian eyes

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    Ekta Rishi

    2012-01-01

    Full Text Available Aim: To evaluate the management outcomes amongst various treatment modalities for submacular hemorrhage (SMH in Indian subjects. Settings and Design: Retrospective, single-center study. Materials and Methods: Patients presenting with SMH between 1999 and 2006 were included. Treatment modalities included: vitrectomy with subretinal recombinant tissue plasminogen activator (r-tPA assisted SMH evacuation (group 1, n = 14; pneumatic displacement with intravitreal r-tPA and gas (group 2, n = 25; and pneumatic displacement with intraocular gas (group 3, n = 7. Favorable anatomical outcome was defined as complete displacement of SMH from fovea and favorable functional outcome was defined as a gain of >2 Snellen lines from the baseline. Kruskal-Wallis, analysis of variance (ANOVA, and Chi-square tests were used to compare the three groups, while Mann-Whitney and independent t-test were used to evaluate the influence of duration and size of SMH on outcomes. Results: There was no difference amongst groups in terms of favorable anatomical (P = 0.121 or functional outcomes (P = 0.611. Eyes with median duration of SMH less than 7.5 days had a significantly higher probability of achieving favorable anatomical outcome compared to eyes with SMH >14.5 days (P = 0.042. However, duration of SMH did not influence functional outcome (P = 0.595. Similarly, size of SMH did not affect anatomical (P = 0.578 or functional (P = 0.381 outcome. Median follow-up was 31.5, 6.5, and 2.5 months in the three groups, respectively. Conclusions: Co- existing posterior segment conditions and duration of SMH may influence the choice of treatment modality and treatment outcomes. Pneumatic displacement with r-tPA and r-tPA assisted vitrectomy appear to be favorable options for the management of SMH.

  5. Reading Mathematics Representations: An Eye-Tracking Study

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    Andrá, Chiara; Lindström, Paulina; Arzarello, Ferdinando; Holmqvist, Kenneth; Robutti, Ornella; Sabena, Cristina

    2015-01-01

    We use eye tracking as a method to examine how different mathematical representations of the same mathematical object are attended to by students. The results of this study show that there is a meaningful difference in the eye movements between formulas and graphs. This difference can be understood in terms of the cultural and social shaping of…

  6. Reading Mathematics Representations: An Eye-Tracking Study

    Science.gov (United States)

    Andrá, Chiara; Lindström, Paulina; Arzarello, Ferdinando; Holmqvist, Kenneth; Robutti, Ornella; Sabena, Cristina

    2015-01-01

    We use eye tracking as a method to examine how different mathematical representations of the same mathematical object are attended to by students. The results of this study show that there is a meaningful difference in the eye movements between formulas and graphs. This difference can be understood in terms of the cultural and social shaping of…

  7. Study of Optical Models Regarding the Human Eye

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    Maryam Abolmasoomi

    2011-03-01

    Full Text Available Introduction: Until now, many models have been presented for optical study of the human eye. In recent years, surgery on the anterior section of the eye (such as cataract and photo-refractive surgery has increased, so a study on the optics of the eye and evaluation of vision quality has become more important. Material and Methods: In this article, some of these models are considered. They include models with spherical and conic-section surfaces (for cornea and lens, simple models and new models with complex surfaces. Results: Evaluation of the optical models of the eye provides the possibility of enhancing the representation of human vision and also increasing the accuracy of surgery on the anterior section of the eye to enable higher quality vision.

  8. Eye Problems May Be Tied to Zika, Lab Study Suggests

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    ... 165947.html Eye Problems May Be Tied to Zika, Lab Study Suggests Work with monkeys indicates birth ... 25, 2017 (HealthDay News) -- Scientists exploring how the Zika virus passes from pregnant monkeys to their fetuses ...

  9. Eye-tracking study of inanimate objects

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    Ković Vanja

    2009-01-01

    Full Text Available Unlike the animate objects, where participants were consistent in their looking patterns, for inanimates it was difficult to identify both consistent areas of fixations and a consistent order of fixations. Furthermore, in comparison to animate objects, in animates received significantly shorter total looking time, shorter longest looks and a smaller number of overall fixations. However, as with animates, looking patterns did not systematically differ between the naming and non-naming conditions. These results suggested that animacy, but not labelling, impacts on looking behavior in this paradigm. In the light of feature-based accounts of semantic memory organization, one could interpret these findings as suggesting that processing of the animate objects is based on the saliency/diagnosticity of their visual features (which is then reflected through participants eye-movements towards those features, whereas processing of the inanimate objects is based more on functional features (which cannot be easily captured by looking behavior in such a paradigm.

  10. A 1-year Study of Eye Trauma at Farabi Hospital

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    J. Faraji Oskooie

    1998-04-01

    Full Text Available The author conducted 1-year study investigating the causation and management of eye trauma at Farabi Eye' center. All patients sustaining eye injuries who were evaluated by ophthalmology service over one year interval were included."n. A formal questionnaire was completed with details of the injuiy being obtained. An ophthalmologic examination was performed on each patient, and examination findings and diagnostic tests obtained, diagnosis and treatment were recorded and analyzed."nNine hundreds and sixty-one injuries (65% occured in males and 503 (35% in females. The average age was 30 years. This study included 1464 eye injuries."nFour handreds and eighty-five (nearly 30% of patients were in pediatric age group. Seventy percent of all patients were admitted within 24 hours of their injury. Fourty percent of all injuries occurred in the street, 30% at home, 15% at the work place , the rest either in school or sport field."nAmong those older than 65 years of age, 70% of injuries were the result of fall. Seventy percent of all eye injuries were caused by blunt trauma. Diagnosis and management were recorded."nConclusions : Tehran and other metropolitans population is more likely to sustain eye trauma as the result of an assault and is less likely to be involved in a work- or sports-related one."nGiven poor compliance without patient management and follow-up, aggressive primary management may be indicated to optimize visual outcome

  11. Study of the Pathogenicity of Aeromonas hydrophila for Man

    Science.gov (United States)

    1984-08-15

    causing diarrhea in humans when 4 challenged with whole, viable cultures. We have conducted a number of studies in Mexico looking at the epidemiology ...were inoculated into the eyes of adult Hartley strain guinea pigs (Charles River, Wilmington, MA). The aminals were examined for keratoconjunctivitis ...hemagglutination patterns were determined using the method of Evans et al. (25). Human (type A), bovine (Flow Laboratories, McLean, Va), chicken (FT-owT

  12. Navigation of the EPOXI Spacecraft to Comet Hartley 2

    Science.gov (United States)

    Bhaskaran, Shyam; Abrahamson, Matt; Chesley, Steven; Chung, Min-Kun; Halsell, Allen; Haw, Robert; Helfrich, Cliff; Jefferson, David; Kennedy, Brian; McElrath, Tim; Owen, William; Rush, Brian; Smith, Jonathon; Wang, Tseng-Chan; Yen, Chen-Wan

    2011-01-01

    On November 4, 2010, the EPOXI spacecraft flew by the comet Hartley 2, marking the fourth time that a NASA spacecraft successfully captured high resolution images of a cometary nucleus. EPOXI is the extended mission of the Deep Impact mission, which delivered an impactor on comet Tempel-1 on July 4, 2005. EPOXI officially started in September 2007 and eventually took over 3 years of flight time and had 3 Earth gravity assists to achieve the proper encounter conditions. In the process, the mission was redesigned to accommodate a new comet as the target and changes in the trajectory to achieve better imaging conditions at encounter. Challenges in navigation of the spacecraft included precision targeting of several Earth flybys and the comet encounter, uncertainties in determining the ephemeris of the comet relative to the spacecraft, and the high accuracy trajectory knowledge needed to image the comet during the encounter. This paper presents an overview of the navigation process used for the mission.

  13. Impact of telephone consent and potential for eye donation in the UK: the Newcastle Eye Centre study

    Science.gov (United States)

    Ting, D S J; Potts, J; Jones, M; Lawther, T; Armitage, W J; Figueiredo, F C

    2016-01-01

    Aims To examine the impact of telephone consent introduced in 2007 on the eye donation rate and to report the changing trend and potential for improvement in eye donation in Newcastle upon Tyne, UK. Methods Relevant data were retrospectively collected from the local eye retrieval database for two separate years, namely, 2006 (before the introduction of telephone consent) and 2010. All the hospitals within Newcastle were included in the study. Results From 2006 to 2010, there was a 3.5-fold increase in eye donation from 32 (of 2479 deaths) to 111 donors per year (of 2213 deaths) in Newcastle (PNewcastle over the recent years. Introduction of telephone consent and high-quality eye donation service serve as effective measures for increasing eye donation. PMID:26514245

  14. M. Hartley Dodge Unit : Great Swamp National Wildlife Refuge : Wilderness area proposal

    Data.gov (United States)

    US Fish and Wildlife Service, Department of the Interior — This document is a brief report on the M. Hartley Dodge Unit of the Great Swamp National Wildlife Refuge and its suitability for wilderness designation. Topics...

  15. David Hartley's views on Madness: With an introduction by GE Berrios.

    Science.gov (United States)

    Berrios, G E

    2015-03-01

    The psychiatric aspects of David Hartley's writings have received less attention than the rest of his work. This Classic Text deals with Section VI of his Observations on Man …, namely, the 'Imperfections of the rational Faculty'. Hartley defines madness as an imperfection of reason that can be temporary or enduring. He makes use of his model of mental functioning to differentiate between eight clinical categories of madness, each representing a different pattern of vibrations of the nerves. Hartley developed this model based on Newton's theory of vibrations and, to explain the complexity of mental acts and entities, he combined it with his own version of the mechanism of Association of Ideas borrowed from John Locke. Much work needs to be done to identify the provenance of Hartley's nosology and nosography. © The Author(s) 2015.

  16. A Fragile Watermarking Based on Separable Discrete Hartley Transform for Color Image Authentication (FWSDHTCIA

    Directory of Open Access Journals (Sweden)

    J. K. Mandal

    2013-01-01

    Full Text Available In this paper, a fragile watermarking based on two-dimensional Separable Discrete Hartley Transform hasbeen proposed for color image authentication (FWSDHTCIA. Two dimensional SDHT is applied on each2 × 2 sub-image block of the carrier image in row major order and produces four frequency components intransform domain. Due to the high sensitivity of human eye on green channel, only one authenticatingmessage/image bit is fabricated at the second bit position of each frequency component for every 2 × 2green sub-matrix. Unlikely, in every 2 × 2 red and blue sub-matrices, two bits from the authenticatingmessage/image are fabricated at the second and third bit position of each frequency component as thehuman eye is less sensitive on red and blue channels as compared to green. After fabricating theauthenticating watermark (message/image, a frequency adjustment strategy has been applied to get backthe less distorted watermarked image in spatial domain. A delicate re-adjustment has been incorporated inthe first frequency component of each 2 × 2 mask, to keep the quantum value positive in spatial domainwithout hampering the authenticating watermark bits. Two dimensional inverse SDHT (ISDHT is appliedon each 2 × 2 sub-mask as post embedding operation to produce the watermarked image. At the receivingend reverse operation is performed to extract the stream which is compared to the original stream forauthentication. Experimental results conform that the proposed algorithm has improvised the payload andPSNR values over SDHTIWCIA [7] scheme which is previously proposed by us. Also, the proposedFWSDHTCIA scheme produces much better result than the Discrete Cosine Transform (DCT, QuaternionFourier Transformation (QFT and Spatio-Chromatic DFT (SCDFT based techniques.

  17. Analysis of neonatal resuscitation using eye tracking: a pilot study.

    Science.gov (United States)

    Law, Brenda Hiu Yan; Cheung, Po-Yin; Wagner, Michael; van Os, Sylvia; Zheng, Bin; Schmölzer, Georg

    2017-08-19

    Visual attention (VA) is important for situation awareness and decision-making. Eye tracking can be used to analyse the VA of healthcare providers. No study has examined eye tracking during neonatal resuscitation. To test the use of eye tracking to examine VA during neonatal resuscitation. Six video recordings were obtained using eye tracking glasses worn by resuscitators during the first 5 min of neonatal resuscitation. Videos were analysed to obtain (i) areas of interest (AOIs), (ii) time spent on each AOI and (iii) frequency of saccades between AOIs. Five videos were of acceptable quality and analysed. Only 35% of VA was directed at the infant, with 33% at patient monitors and gauges. There were frequent saccades (0.45/s) and most involved patient monitors. During neonatal resuscitation, VA is often directed away from the infant towards patient monitors. Eye tracking can be used to analyse human performance during neonatal resuscitation. © Article author(s) (or their employer(s) unless otherwise stated in the text of the article) 2017. All rights reserved. No commercial use is permitted unless otherwise expressly granted.

  18. Human volunteer study with PGME: Eye irritation during vapour exposure

    NARCIS (Netherlands)

    Emmen, H.H.; Muijser, H.; Arts, J.H.E.; Prinsen, M.K.

    2003-01-01

    The objective of this study was to establish the possible occurrence of eye irritation and subjective symptoms in human volunteers exposed to propylene glycol monomethyl ether (PGME) vapour at concentrations of 0, 100 and 150 ppm. Testing was conducted in 12 healthy male volunteers using a repeated

  19. Development of Text Reading in Japanese: An Eye Movement Study

    Science.gov (United States)

    Jincho, Nobuyuki; Feng, Gary; Mazuka, Reiko

    2014-01-01

    This study examined age-group differences in eye movements among third-grade, fifth-grade, and adult Japanese readers. In Experiment 1, Japanese children, but not adults, showed a longer fixation time on logographic kanji words than on phonologically transparent hiragana words. Further, an age-group difference was found in the first fixation…

  20. Human volunteer study with PGME: Eye irritation during vapour exposure

    NARCIS (Netherlands)

    Emmen, H.H.; Muijser, H.; Arts, J.H.E.; Prinsen, M.K.

    2003-01-01

    The objective of this study was to establish the possible occurrence of eye irritation and subjective symptoms in human volunteers exposed to propylene glycol monomethyl ether (PGME) vapour at concentrations of 0, 100 and 150 ppm. Testing was conducted in 12 healthy male volunteers using a repeated

  1. The Rotation State of Comet 103P/Hartley 2

    Science.gov (United States)

    Farnham, Tony; Knight, Matthew M.; Schleicher, David G.

    2016-10-01

    On November 4, 2010, the Deep Impact (DI) spacecraft made its closest approach to comet 103P/Hartley 2, passing only 694 km from the nucleus. Observations of the coma produced a lightcurve that shows the nucleus is in a state of non-principal axis rotation that evolves with time, while other observations revealed a nucleus that has concentrated collimated jets driven by CO2 emission (A'Hearn et al., 2011), large variability in the production of H2O and CO2 (Besse et al. 2016), and ice patches on the surface (Sunshine et al. 2011). To properly interpret the significance of these phenomena, it is necessary to understand the rotation of the nucleus, so that its thermal history can be derived and properly modeled, while at the same time, it is likely that the comet's high activity levels play an important role in the nucleus dynamics.An analysis of the lightcurve by Belton et al (2013) described the comet's rotation state, with two periodicities (primary of 18 h, secondary of 28 or 55 h) that change with time. Although their solution describes the periodicities observed around closest approach, it is insufficient to reproduce the changes in coma morphology with time. We are performing an analysis of the structures in the coma (Farnham 2009), using Monte Carlo routines to model the outflowing dust produced by active sources on the nucleus, to derive a comprehensive solution for the nucleus' rotation.We are also obtaining new observations of Hartley 2 in June/July 2016 (r~3.2 AU) to measure the nucleus' primary component period before the comet becomes highly active. This will provide an end-state measure of the rotation from the 2010 apparition, as well as a starting value for the current apparition, to allow its continuing evolution to be monitored. We will present an update on the status and preliminary results of these analyses.This work is funded by NASA Grant NNX12AQ64G.A'Hearn, M.F., et al. (2011) Science 332, 1396-1400Belton M.J.S., et al. (2013) Icarus 222, 595

  2. Fast estimate of Hartley entropy in image sharpening

    Science.gov (United States)

    Krbcová, Zuzana; Kukal, Jaromír.; Svihlik, Jan; Fliegel, Karel

    2016-09-01

    Two classes of linear IIR filters: Laplacian of Gaussian (LoG) and Difference of Gaussians (DoG) are frequently used as high pass filters for contextual vision and edge detection. They are also used for image sharpening when linearly combined with the original image. Resulting sharpening filters are radially symmetric in spatial and frequency domains. Our approach is based on the radial approximation of unknown optimal filter, which is designed as a weighted sum of Gaussian filters with various radii. The novel filter is designed for MRI image enhancement where the image intensity represents anatomical structure plus additive noise. We prefer the gradient norm of Hartley entropy of whole image intensity as a measure which has to be maximized for the best sharpening. The entropy estimation procedure is as fast as FFT included in the filter but this estimate is a continuous function of enhanced image intensities. Physically motivated heuristic is used for optimum sharpening filter design by its parameter tuning. Our approach is compared with Wiener filter on MRI images.

  3. Individual Differences in Spatial Orientation Performances: An Eye Tracking Study

    Directory of Open Access Journals (Sweden)

    Sacide Güzin Mazman

    2013-08-01

    Full Text Available This paper includes two studies. In study 1, the computerized version of Spatial Orientation Test (Kozhevnikov & Hegarty, 2001 was standardized for determining the norm values for Turkish undergraduate students as well as demonstrating the reliability and validity of the test. In Study 1, 101 undergraduate students from two different departments were recruited and the data were collected with computerized spatial orientation test together with a demographic information form. Descriptive statistics, independent sample t test and one way ANOVA were used in data analysis. Statistical analyses revealed out that gender and years of computer experience have significant effect on spatial orientation ability scores. Test-retest reliability coefficient was found for total accuracy score as r= .778 and r=.634 for total reaction time. As a result of discriminant validity study, the correlation between the spatial orientation and mental rotation test scores was found to be very low and not significant. In study 2, individual differences between low and high spatial orientation ability groups during performing “Spatial Orientation Test” were examined through eye movements. Five high and five low spatial orientation ability level students were asked to participate in the second study. While performing Spatial Orientation Test, their eye movements were recorded. The findings indicated that there were significant differences in eye movements between different spatial orientation ability levels in terms of fixation duration. Furthermore it was found that high and low level spatial orientation level groups solved problems with different solution patterns.

  4. NMR spectroscopy applied to the eye: Drugs and metabolic studies

    Energy Technology Data Exchange (ETDEWEB)

    Saether, Oddbjoern

    2005-07-01

    NMR spectroscopy has been extensively applied in biomedical research during the last decades. It has proved to be an analytical tool of great value. From being mainly used in chemistry, technological developments have expanded the application of NMR spectroscopy to a great wealth of disciplines. With this method, biochemical information can be obtained by analysing tissue extracts. Moreover, NMR spectroscopy is increasingly employed for pharmacokinetic studies and analysis of biofluids. Technological progress has provided increased sensitivity and resolution in the spectra, which enable even more of the complexity of biological samples to be elucidated. With the implementation of high-resolution magic angle spinning (HR-MAS) NMR spectroscopy in biomedicine, intact tissue samples or biopsies can be investigated. Thus, NMR spectroscopy has an ever-increasing impact in metabolic screening of human samples and in animal models, and methods are also increasingly realised in vivo. The present work, NMR spectroscopy applied to eye research, consists of two main parts. Firstly, the feasibility to monitor fluorinated ophthalmic drugs directly in the eye was assessed. Secondly, HR-MAS H1 NMR spectroscopy was applied for metabolic profiling of the anterior eye segment, specifically to analyse metabolic changes in intact corneal and lenticular samples after cataractogenic insults. This work included metabonomics with the application of pattern recognition methods to analyse HR-MAS spectra of eye tissues. Optimisation strategies were explored for F19 NMR detection of fluorinated drugs in a phantom eye. S/N gains in F19 NMR spectroscopy were achieved by implementing time-share H1 decoupling at 2.35 T. The method is advantageous for compounds displaying broad spectral coupling patterns, though detection of drugs at concentrations encountered in the anterior eye segment after topical application was not feasible. Higher magnetic fields and technological improvements could enable

  5. Application of 3-dimensional printing technology to construct an eye model for fundus viewing study.

    Directory of Open Access Journals (Sweden)

    Ping Xie

    Full Text Available To construct a life-sized eye model using the three-dimensional (3D printing technology for fundus viewing study of the viewing system.We devised our schematic model eye based on Navarro's eye and redesigned some parameters because of the change of the corneal material and the implantation of intraocular lenses (IOLs. Optical performance of our schematic model eye was compared with Navarro's schematic eye and other two reported physical model eyes using the ZEMAX optical design software. With computer aided design (CAD software, we designed the 3D digital model of the main structure of the physical model eye, which was used for three-dimensional (3D printing. Together with the main printed structure, polymethyl methacrylate(PMMA aspherical cornea, variable iris, and IOLs were assembled to a physical eye model. Angle scale bars were glued from posterior to periphery of the retina. Then we fabricated other three physical models with different states of ammetropia. Optical parameters of these physical eye models were measured to verify the 3D printing accuracy.In on-axis calculations, our schematic model eye possessed similar size of spot diagram compared with Navarro's and Bakaraju's model eye, much smaller than Arianpour's model eye. Moreover, the spherical aberration of our schematic eye was much less than other three model eyes. While in off- axis simulation, it possessed a bit higher coma and similar astigmatism, field curvature and distortion. The MTF curves showed that all the model eyes diminished in resolution with increasing field of view, and the diminished tendency of resolution of our physical eye model was similar to the Navarro's eye. The measured parameters of our eye models with different status of ametropia were in line with the theoretical value.The schematic eye model we designed can well simulate the optical performance of the human eye, and the fabricated physical one can be used as a tool in fundus range viewing research.

  6. Biocompatibility and biodegradation studies of subconjunctival implants in rabbit eyes.

    Directory of Open Access Journals (Sweden)

    Yan Peng

    Full Text Available Sustained ocular drug delivery is difficult to achieve. Most drugs have poor penetration due to the multiple physiological barriers of the eye and are rapidly cleared if applied topically. Biodegradable subconjunctival implants with controlled drug release may circumvent these two problems. In our study, two microfilms (poly [d,l-lactide-co-glycolide] PLGA and poly[d,l-lactide-co-caprolactone] PLC were developed and evaluated for their degradation behavior in vitro and in vivo. We also evaluated the biocompatibility of both microfilms. Eighteen eyes (9 rabbits were surgically implanted with one type of microfilm in each eye. Serial anterior-segment optical coherence tomography (AS-OCT scans together with serial slit-lamp microscopy allowed us to measure thickness and cross-sectional area of the microfilms. In vitro studies revealed bulk degradation kinetics for both microfilms, while in vivo studies demonstrated surface erosion kinetics. Serial slit-lamp microscopy revealed no significant inflammation or vascularization in both types of implants (mean increase in vascularity grade PLGA50/50 12±0.5% vs. PLC70/30 15±0.6%; P = 0.91 over a period of 6 months. Histology, immunohistochemistry and immuno-fluorescence also revealed no significant inflammatory reaction from either of the microfilms, which confirmed that both microfilms are biocompatible. The duration of the drug delivery can be tailored by selecting the materials, which have different degradation kinetics, to suit the desired clinical therapeutic application.

  7. Implementación en Sistemas Embebidos de la Transformada Discreta de Hartley

    Directory of Open Access Journals (Sweden)

    Juan S. Botero-Valencia

    2010-06-01

    Full Text Available Orthogonal transformations have been very useful in the characterization and signal processing. In particular Hartley Transform allows for time-frequency representations and vice versa. This paper presents an algorithm for calculating the Discrete Hartley Transform in embedded systems with the objective of minimizing the computational load and storage capacity required. It exploits the similarity with the Discrete Fourier Transform to use a fast algorithm reduces the number of trigonometric functions calculated using the rotation factors (Twiddle factors. In general, the implementation can increase the size of the processing window and increase computational speed compared to direct calculation.

  8. Phase image encryption in the fractional Hartley domain using Arnold transform and singular value decomposition

    Science.gov (United States)

    Singh, Phool; Yadav, A. K.; Singh, Kehar

    2017-04-01

    A novel scheme for image encryption of phase images is proposed, using fractional Hartley transform followed by Arnold transform and singular value decomposition in the frequency domain. Since the plaintext is a phase image, the mask used in the spatial domain is a random amplitude mask. The proposed scheme has been validated for grayscale images and is sensitive to the encryption parameters such as the order of the Arnold transform and the fractional orders of the Hartley transform. We have also evaluated the scheme's resistance to the well-known noise and occlusion attacks.

  9. Optical color image hiding scheme based on chaotic mapping and Hartley transform

    Science.gov (United States)

    Liu, Zhengjun; Zhang, Yu; Liu, Wei; Meng, Fanyi; Wu, Qun; Liu, Shutian

    2013-08-01

    We present a color image encryption algorithm by using chaotic mapping and Hartley transform. The three components of color image are scrambled by Baker mapping. The coordinates composed of the scrambled monochrome components are converted from Cartesian coordinates to spherical coordinates. The data of azimuth angle is normalized and regarded as the key. The data of radii and zenith angle are encoded under the help of optical Hartley transform with scrambled key. An electro-optical encryption structure is designed. The final encrypted image is constituted by two selected color components of output in real number domain.

  10. Associations between subjective happiness and dry eye disease: a new perspective from the Osaka study.

    Science.gov (United States)

    Kawashima, Motoko; Uchino, Miki; Yokoi, Norihiko; Uchino, Yuichi; Dogru, Murat; Komuro, Aoi; Sonomura, Yukiko; Kato, Hiroaki; Kinoshita, Shigeru; Mimura, Masaru; Tsubota, Kazuo

    2015-01-01

    Dry eye disease has become an important health problem. A lack of concordance between self-reported symptoms and the outcome of dry eye examinations has raised questions about dry eye disease. To explore the association between subjective happiness and objective and subjective symptoms of dry eye disease. The study adopted a cross-sectional design. All the employees of a company in Osaka, Japan. 672 Japanese office workers using Visual Display Terminals (age range: 26-64 years). The dry eye measurement tools included the Schirmer test, conjunctivocorneal staining, the tear film break-up time, as well as the administration of a dry eye symptoms questionnaire. Happiness was measured by the Subjective Happiness Scale. Dry eye examination parameters, dry eye symptoms questionnaires, and the Subjective Happiness Scale score. Of the 672 workers, 561 (83.5%) completed the questionnaires and examinations. The mean Subjective Happiness Scale score was 4.91 (SD = 1.01). This score was inversely correlated with the dry eye symptom score (r = -0.188, p happiness was the lowest in the group without objective results, but reported subjective symptoms of dry eyes (p happiness and self-reported symptoms of dry eyes. Findings of this study revealed a new perspective on dry eye disease, including the potential for innovative treatments of a specific population with dry eye disease.

  11. When art moves the eyes: a behavioral and eye-tracking study.

    Science.gov (United States)

    Massaro, Davide; Savazzi, Federica; Di Dio, Cinzia; Freedberg, David; Gallese, Vittorio; Gilli, Gabriella; Marchetti, Antonella

    2012-01-01

    The aim of this study was to investigate, using eye-tracking technique, the influence of bottom-up and top-down processes on visual behavior while subjects, naïve to art criticism, were presented with representational paintings. Forty-two subjects viewed color and black and white paintings (Color) categorized as dynamic or static (Dynamism) (bottom-up processes). Half of the images represented natural environments and half human subjects (Content); all stimuli were displayed under aesthetic and movement judgment conditions (Task) (top-down processes). Results on gazing behavior showed that content-related top-down processes prevailed over low-level visually-driven bottom-up processes when a human subject is represented in the painting. On the contrary, bottom-up processes, mediated by low-level visual features, particularly affected gazing behavior when looking at nature-content images. We discuss our results proposing a reconsideration of the definition of content-related top-down processes in accordance with the concept of embodied simulation in art perception.

  12. When art moves the eyes: a behavioral and eye-tracking study.

    Directory of Open Access Journals (Sweden)

    Davide Massaro

    Full Text Available The aim of this study was to investigate, using eye-tracking technique, the influence of bottom-up and top-down processes on visual behavior while subjects, naïve to art criticism, were presented with representational paintings. Forty-two subjects viewed color and black and white paintings (Color categorized as dynamic or static (Dynamism (bottom-up processes. Half of the images represented natural environments and half human subjects (Content; all stimuli were displayed under aesthetic and movement judgment conditions (Task (top-down processes. Results on gazing behavior showed that content-related top-down processes prevailed over low-level visually-driven bottom-up processes when a human subject is represented in the painting. On the contrary, bottom-up processes, mediated by low-level visual features, particularly affected gazing behavior when looking at nature-content images. We discuss our results proposing a reconsideration of the definition of content-related top-down processes in accordance with the concept of embodied simulation in art perception.

  13. Eye-Tracking in the Study of Visual Expertise: Methodology and Approaches in Medicine

    Science.gov (United States)

    Fox, Sharon E.; Faulkner-Jones, Beverly E.

    2017-01-01

    Eye-tracking is the measurement of eye motions and point of gaze of a viewer. Advances in this technology have been essential to our understanding of many forms of visual learning, including the development of visual expertise. In recent years, these studies have been extended to the medical professions, where eye-tracking technology has helped us…

  14. Subfoveal choroidal thickness and glaucoma. The Beijing Eye Study 2011.

    Directory of Open Access Journals (Sweden)

    Ya Xing Wang

    Full Text Available To examine subfoveal choroidal thickness (SFCT in eyes with glaucoma, using enhanced depth imaging spectral domain optical coherence tomography.The population-based Beijing Eye Study 2011 included 3468 individuals with a mean age of 64.6 ± 9.8 years (range: 50-93 years. A detailed ophthalmic examination was performed including spectral-domain optical coherence tomography (SD-OCT with enhanced depth imaging for measurement of SFCT, and assessment of fundus photographs for presence of glaucoma. In addition, the group of patients with chronic angle-closure glaucoma (ACG from the Beijing Eye Study (n = 37 was merged with a group of patients with chronic ACG from the Tongren hospital (n = 52.Assessments of SFCT and glaucoma were available for 3232 (93.2% subjects. After adjusting for age, axial length, gender, anterior chamber and lens thickness, SFCT was not significantly associated with presence of glaucoma (P = 0.08; regression coefficient B:-15.7. As a corollary, in logistic regression analysis with adjustment for age, axial length and intraocular pressure, presence of glaucoma was not significantly associated with SFCT (P = 0.20. If only open-angle glaucoma was considered, multivariate analysis revealed no significant association between SFCT and presence of open-angle glaucoma (P = 0.44. As a corollary, in logistic regression analysis, open-angle glaucoma was not significantly associated with SFCT (P = 0.91. In a similar manner if only ACG was taken into account, SFCT was not significantly associated with the presence of ACG (P = 0.27 in multivariate analysis. As a corollary in binary regression analysis, presence of ACG was not significantly associated with SFCT (P = 0.27.In multivariate analysis with adjustment for age, axial length, gender, anterior chamber and lens thickness, neither OAG nor ACG was associated with an abnormal SFCT.

  15. Eye trauma

    African Journals Online (AJOL)

    2011-02-02

    Feb 2, 2011 ... will invariably lead to lid swelling, making the examination far more difficult. ... protect the eye with a pad or shield, give tetanus prophylaxis and refer. ... A study on penetrating eye injuries in South African children found.

  16. Eye Health in New Zealand: A Study of Public Knowledge, Attitudes, and Practices Related to Eye Health and Disease

    Science.gov (United States)

    Ahn, Mark J.; Frederikson, Lesley; Borman, Barry; Bednarek, Rebecca

    2011-01-01

    Purpose: This study seeks to measure the public knowledge, attitudes, and practices related to eye health and disease in New Zealand (NZ). Design/methodology/approach: A 22-item survey of 507 adults in NZ was conducted. The survey was developed using interviews and focus groups, as well as comparisons with other benchmark international studies.…

  17. Eye Health in New Zealand: A Study of Public Knowledge, Attitudes, and Practices Related to Eye Health and Disease

    Science.gov (United States)

    Ahn, Mark J.; Frederikson, Lesley; Borman, Barry; Bednarek, Rebecca

    2011-01-01

    Purpose: This study seeks to measure the public knowledge, attitudes, and practices related to eye health and disease in New Zealand (NZ). Design/methodology/approach: A 22-item survey of 507 adults in NZ was conducted. The survey was developed using interviews and focus groups, as well as comparisons with other benchmark international studies.…

  18. Using Eye Tracking to Assess Reading Performance in Patients with Glaucoma: A Within-Person Study

    Directory of Open Access Journals (Sweden)

    Nicholas D. Smith

    2014-01-01

    Full Text Available Reading is often cited as a demanding task for patients with glaucomatous visual field (VF loss, yet reading speed varies widely between patients and does not appear to be predicted by standard visual function measures. This within-person study aimed to investigate reading duration and eye movements when reading short passages of text in a patient’s worse eye (most VF damage when compared to their better eye (least VF damage. Reading duration and saccade rate were significantly different on average in the worse eye when compared to the better eye (P<0.001 in 14 patients with glaucoma that had median (interquartile range between-eye difference in mean deviation (MD; a standard clinical measure for VF loss of 9.8 (8.3 to 14.8 dB; differences were not related to the size of the difference in MD between eyes. Patients with a more pronounced effect of longer reading duration on their worse eye made a larger proportion of “regressions” (backward saccades and “unknown” EMs (not adhering to expected reading patterns when reading with the worse eye when compared to the better eye. A between-eye study in patients with asymmetric disease, coupled with eye tracking, provides a useful experimental design for exploring reading performance in glaucoma.

  19. Quantitative Assessment of Eye Phenotypes for Functional Genetic Studies Using Drosophila melanogaster

    Science.gov (United States)

    Iyer, Janani; Wang, Qingyu; Le, Thanh; Pizzo, Lucilla; Grönke, Sebastian; Ambegaokar, Surendra S.; Imai, Yuzuru; Srivastava, Ashutosh; Troisí, Beatriz Llamusí; Mardon, Graeme; Artero, Ruben; Jackson, George R.; Isaacs, Adrian M.; Partridge, Linda; Lu, Bingwei; Kumar, Justin P.; Girirajan, Santhosh

    2016-01-01

    About two-thirds of the vital genes in the Drosophila genome are involved in eye development, making the fly eye an excellent genetic system to study cellular function and development, neurodevelopment/degeneration, and complex diseases such as cancer and diabetes. We developed a novel computational method, implemented as Flynotyper software (http://flynotyper.sourceforge.net), to quantitatively assess the morphological defects in the Drosophila eye resulting from genetic alterations affecting basic cellular and developmental processes. Flynotyper utilizes a series of image processing operations to automatically detect the fly eye and the individual ommatidium, and calculates a phenotypic score as a measure of the disorderliness of ommatidial arrangement in the fly eye. As a proof of principle, we tested our method by analyzing the defects due to eye-specific knockdown of Drosophila orthologs of 12 neurodevelopmental genes to accurately document differential sensitivities of these genes to dosage alteration. We also evaluated eye images from six independent studies assessing the effect of overexpression of repeats, candidates from peptide library screens, and modifiers of neurotoxicity and developmental processes on eye morphology, and show strong concordance with the original assessment. We further demonstrate the utility of this method by analyzing 16 modifiers of sine oculis obtained from two genome-wide deficiency screens of Drosophila and accurately quantifying the effect of its enhancers and suppressors during eye development. Our method will complement existing assays for eye phenotypes, and increase the accuracy of studies that use fly eyes for functional evaluation of genes and genetic interactions. PMID:26994292

  20. How do we see art: an eye-tracker study

    Directory of Open Access Journals (Sweden)

    Rodrigo eQuian Quiroga

    2011-09-01

    Full Text Available We describe the pattern of fixations of subjects looking at figurative and abstract paintings from different artists (Molina, Mondrian, Rembrandt, della Francesca and at modified versions in which different aspects of these art pieces were altered with simple digital manipulations. We show that the fixations of the subjects followed some general common principles (e.g. being attracted to saliency regions but with a large variability for the figurative paintings, according to the subject’s personal appreciation and knowledge. In particular, we found different gazing patterns depending on whether the subject saw the original or the modified version of the painting first. We conclude that the study of gazing patterns obtained by using the eye-tracker technology give a useful approach to quantify how subjects observe art.

  1. Association between eye dominance and training for rifle marksmanship: a pilot study.

    Science.gov (United States)

    Jones, L F; Classe, J G; Hester, M; Harris, K

    1996-02-01

    This pilot study was performed to determine the effect, if any, exerted by crossed dominance (contralateral hand and eye dominance) on the ability of novice riflemen to learn how to accurately shoot a rifle. Sighting dominance was used to determine the dominant eye. Hand dominance was determined by the arm used to shoulder the rifle in the shooting position. Subjects were 308 military recruits at the Fort Benning Army Base in Columbus, Georgia, who had undergone basic training in rifle marksmanship. Qualification scores obtained at the base rifle range were used to measure the subjects' ability to learn marksmanship skills. The subjects with right-hand/right-eye and left-hand/left-eye (uncrossed) dominance had qualification scores that were significantly higher (p = .009) than the subjects with right hand/left-eye and left-hand/right-eye (crossed) dominance. A significantly higher percentage of subjects with uncrossed dominance achieved rifle qualification (86.1 percent) than subjects with crossed dominance (56.5 percent) (p = .000). The learning of rifle marksmanship is influenced by eye dominance. Individuals who shoot right handed and are left-eye dominant or who shoot left handed and are right-eye dominant do not learn marksmanship skills as readily as individuals who have matched eye and hand dominance. Since crossed hand and eye dominance can be easily determined, it should be possible to identify cross dominant individuals and provide them with special training so that they can perform at a higher level of skill.

  2. [The antiallergic eye drops "polynadyme": development, experimental and clinical studies].

    Science.gov (United States)

    Maĭchuk, Iu F; Pozdniakov, V I; Pozdniakova, V V; Iakushina, L N

    2006-01-01

    The antiallergic eye drops "Polynadyme", proposed by the Helmgolz Moscow Research Institute of Eye Diseases, have been prepared by the "Sintez" PJSC (Kurgan). The drops exert a combination of antihistaminic and vasoconstrictive effects and, for better tolerability, contain a low-toxic preserving complex. The drops are polymer-based, which ensures a long action and an artificial tear effect. Preclinical rabbit trials have shown the safety of the "Polynadyme" eye drops, their specific activity in preventing an allergic reaction, and their antiallergic effect on a model of allergic conjunctivitis. Comparative clinical trials covering 150 patients have yielded excellent and good results in 93% of cases. In acute allergic reactions, hyperemia, itch, and burning diminished just 5 minutes after administration. The "Polynadyme" eye drops are effective in treating pollinous conjunctivitis, spring (vernal) keratoconjunctivitis, allergic reactions when wearing contact lenses, the dry eye syndrome, drug-induced and toxicoallergic conjunctivitis, and other ocular allergic reactions.

  3. Spontaneous osteoarthritis in Dunkin Hartley guinea pigs: histologic, radiologic, and biochemical changes.

    Science.gov (United States)

    Jimenez, P A; Glasson, S S; Trubetskoy, O V; Haimes, H B

    1997-12-01

    Dunkin Hartley guinea pigs develop spontaneous, age-related osteoarthritis (OA) of the knee and other joints. Histologic changes are observed beginning at 3 months of age. Disease severity increases with age, and at 18 months moderate to severe OA is observed. A study was undertaken to assess the morphologic and biochemical changes of 22-month-old animals, and to compare them with values in 2-month-old guinea pigs. Biochemical indices characteristic of OA, from tibial cartilage, indicated an increase in proteoglycan content from 233 +/- 2 micrograms/mg (mean +/- SEM) at 2 months of age to 365 +/- 6 micrograms/mg at 22 months. Collagen concentration in cartilage decreased from 364 +/- 2 micrograms/mg at 2 months to 223 +/- 3 micrograms/mg at 22 months. Proteoglycan fragments found in synovial fluid measured 4.6 +/- 1 micrograms/ml at 2 months and increased to 37 +/- 2 micrograms/ml at 22 months. Radiographic changes observed at 22 months included marginal osteophytes of the tibia and femur, sclerosis of the subchondral bone of the tibial plateau, femoral condyle cysts, and calcification of the collateral ligaments. Histologic evaluation revealed severe OA, with a Mankin score of 10.7 +/- 0.5 in 22-month-old animals. In contrast, 2-month-old animals had no histologic or radiographically detectable lesions. The results of the study reported here indicate that the lesions observed in this model are similar to those of human OA. Spontaneous development of OA in guinea pigs is amenable to the study of the pathogenesis of OA and to the evaluation of potential disease-modifying agents.

  4. Comparative Study of Anterior Eye Segment Measurements with Spectral Swept-Source and Time-Domain Optical Coherence Tomography in Eyes with Corneal Dystrophies

    Directory of Open Access Journals (Sweden)

    Anna K. Nowinska

    2015-01-01

    Full Text Available Purpose. To compare anterior eye segment measurements and morphology obtained with two optical coherence tomography systems (TD OCT, SS OCT in eyes with corneal dystrophies (CDs. Methods. Fifty healthy volunteers (50 eyes and 54 patients (96 eyes diagnosed with CD (epithelial basement membrane dystrophy, EBMD = 12 eyes; Thiel-Behnke CD = 6 eyes; lattice CD TGFBI type = 15 eyes; granular CD type 1 = 7 eyes, granular CD type 2 = 2 eyes; macular CD = 23 eyes; and Fuchs endothelial CD = 31 eyes were recruited for the study. Automated and manual central corneal thickness (aCCT, mCCT, anterior chamber depth (ACD, and nasal and temporal trabecular iris angle (nTIA, tTIA were measured and compared with Bland-Altman plots. Results. Good agreement between the TD and SS OCT measurements was demonstrated for mCCT and aCCT in normal individuals and for mCCT in the CDs group. The ACD, nTIA, and tTIA measurements differed significantly in both groups. TBCD, LCD, and FECD caused increased CCT. MCD caused significant corneal thinning. FECD affected all analyzed parameters. Conclusions. Better agreement between SS OCT and TD OCT measurements was demonstrated in normal individuals compared to the CDs group. OCT provides comprehensive corneal deposits analysis and demonstrates the association of CD with CCT, ACD, and TIA measurements.

  5. Mobile eye-tracking methods in studies of audience learning in health promotion exhibitions

    DEFF Research Database (Denmark)

    Magnussen, Rikke; Zachariassen, Maria; Kharlamov, Nikita

    2017-01-01

    This paper presents a methodological discussion of the potential and challenges of involving mobile eye tracking technology in studies of knowledge generation and learning in a science centre context. The methodological exploration is based on eye-tracking studies of audience interaction...... target groups were families with children age 6–12 years and school classes with students from 4th to 6th grade. The main purpose of the study was to understand the methodological potential and challenges mobile eye tracking comprises during the different stages of research on informal e......-learning in a science centre context utilising digital platforms to enhance informal learning and interaction. The paper presents how eye-tracking methods influence research on: 1) an interventional level: what role eye tracking and eye-tracking equipment plays in interventions; 2) a data level: what new types of data...

  6. Basic Studies of Nonlinear Optical Materials for Eye and Sensor Protection

    Science.gov (United States)

    2004-03-10

    1 BASIC STUDIES OF NONLINEAR OPTICAL MATERIALS FOR EYE AND SENSOR PROTECTION I. Abstract: We have studied the spectroscopy, kinetics and...study liquid or solid materials from CW to 100x10-15 seconds. Basic Studies of Nonlinear Optical Materials for Eye and Sensor Protection

  7. Associations between subjective happiness and dry eye disease: a new perspective from the Osaka study.

    Directory of Open Access Journals (Sweden)

    Motoko Kawashima

    Full Text Available Dry eye disease has become an important health problem. A lack of concordance between self-reported symptoms and the outcome of dry eye examinations has raised questions about dry eye disease.To explore the association between subjective happiness and objective and subjective symptoms of dry eye disease.The study adopted a cross-sectional design.All the employees of a company in Osaka, Japan.672 Japanese office workers using Visual Display Terminals (age range: 26-64 years.The dry eye measurement tools included the Schirmer test, conjunctivocorneal staining, the tear film break-up time, as well as the administration of a dry eye symptoms questionnaire. Happiness was measured by the Subjective Happiness Scale.Dry eye examination parameters, dry eye symptoms questionnaires, and the Subjective Happiness Scale score.Of the 672 workers, 561 (83.5% completed the questionnaires and examinations. The mean Subjective Happiness Scale score was 4.91 (SD = 1.01. This score was inversely correlated with the dry eye symptom score (r = -0.188, p < 0.001, but was not associated with objective findings which include conjunctivocorneal staining, low Schirmer test score, or low tear film break-up time. The level of subjective happiness was the lowest in the group without objective results, but reported subjective symptoms of dry eyes (p < 0.05.There is evidence of the relationship between subjective happiness and self-reported symptoms of dry eyes. Findings of this study revealed a new perspective on dry eye disease, including the potential for innovative treatments of a specific population with dry eye disease.

  8. Improved FHT Algorithms for Fast Computation of the Discrete Hartley Transform

    Directory of Open Access Journals (Sweden)

    M. T. Hamood

    2013-05-01

    Full Text Available In this paper, by using the symmetrical properties of the discrete Hartley transform (DHT, an improved radix-2 fast Hartley transform (FHT algorithm with arithmetic complexity comparable to that of the real-valued fast Fourier transform (RFFT is developed. It has a simple and regular butterfly structure and possesses the in-place computation property. Furthermore, using the same principles, the development can be extended to more efficient radix-based FHT algorithms. An example for the improved radix-4 FHT algorithm is given to show the validity of the presented method. The arithmetic complexity for the new algorithms are computed and then compared with the existing FHT algorithms. The results of these comparisons have shown that the developed algorithms reduce the number of multiplications and additions considerably.

  9. Peripapillary Choroidal Thickness in Adult Chinese: The Beijing Eye Study.

    Science.gov (United States)

    Jiang, Ran; Wang, Ya Xing; Wei, Wen Bin; Xu, Liang; Jonas, Jost B

    2015-06-01

    To measure peripapillary choroidal thickness (PPCT) and to assess its associations. The population-based cross-sectional Beijing Eye Study 2011 included 3468 participants. Detailed medical and ophthalmic examinations were performed. We measured PPCT by spectral-domain optical coherence tomography (SD-OCT) with a 3.4-mm scan circle centered on the optic nerve head. Peripapillary choroidal thickness measurements were available for 3060 (88.2%) study participants with a mean age of 64.4 ± 9.6 years (range, 50-93 years). Mean global PPCT was 134 ± 53 μm (range, 35-348 μm). Peripapillary choroid was thickest in the superior region (155 ± 60 μm), followed by the temporal region (144 ± 75 μm; P region (139 ± 55 μm; P region (110 ± 45 μm; P 0.05) associated with blood pressure, blood concentration of lipids, intraocular pressure and prevalence of glaucoma, diabetic retinopathy, and retinal vein occlusions. The decrease of PPCT with longer axial length occurred predominantly in the temporal region. Peripapillary choroidal thickness is thickest superiorly and thinnest inferiorly. It decreases by 2 μm per year of life and by 5 μm per diopter of myopia. Thinner PPCT is correlated with larger parapapillary α and β zones. The association of thinner PPCT with lower best corrected visual acuity may warrant further study.

  10. Relation between Type-II Discrete Sine Transform and Type -I Discrete Hartley Transform

    Directory of Open Access Journals (Sweden)

    M.Narayan Murty

    2017-06-01

    Full Text Available In this paper, a relation for finding type-II discrete sine transform (DST from type-I discrete Hartley transform (DHT has been derived. The transform length N is taken as even. Using this relation, the (N - 1 output components of DST can be realized from DHT. The DHT is one of the transforms used for converting data in time domain into frequency domain using only real values.

  11. Moment-based method for computing the two-dimensional discrete Hartley transform

    Science.gov (United States)

    Dong, Zhifang; Wu, Jiasong; Shu, Huazhong

    2009-10-01

    In this paper, we present a fast algorithm for computing the two-dimensional (2-D) discrete Hartley transform (DHT). By using kernel transform and Taylor expansion, the 2-D DHT is approximated by a linear sum of 2-D geometric moments. This enables us to use the fast algorithms developed for computing the 2-D moments to efficiently calculate the 2-D DHT. The proposed method achieves a simple computational structure and is suitable to deal with any sequence lengths.

  12. Shape, Density, and Geology of the Nucleus of Comet 103P/Hartley 2

    Science.gov (United States)

    Thomas, P.C.; A'hearn, Michael F.; Veverka, Joseph; Belton, Michael J. S.; Kissel, Jochen; Belton, Michael J. S.; Klaasen, Kenneth P.; McFadden, Lucy A.; Melosh, H. Jay; Schultz, Peter H.; Besse, Sebastien; Carcich, Brian T.; Farnham, Tony L.; Groussin, Olivier; Hermalyn, Brendan; Li, Jian-Yang; Lindler, Don J.; Lisse, Carey M.; Meech, Karen; Richardson, James E.

    2013-01-01

    Data from the Extrasolar Planet Observation and Deep Impact Extended Investigation (EPOXI) mission show Comet 103P/Hartley 2 is a bi-lobed, elongated, nearly axially symmetric comet 2.33 km in length. Surface features are primarily small mounds 1%. The shape may be the evolutionary product of insolation, sublimation, and temporary deposition of materials controlled by the object’s complex rotation.

  13. Normal macular thickness measurements using optical coherence tomography in healthy eyes of adult Chinese persons: the Handan Eye Study.

    Science.gov (United States)

    Duan, Xin Rong; Liang, Yuan Bo; Friedman, David S; Sun, Lan Ping; Wong, Tien Yin; Tao, Qiu Shan; Bao, Lingzhi; Wang, Ning Li; Wang, Jie Jin

    2010-08-01

    To describe macular thickness measured by optical coherence tomography (OCT) in healthy eyes of adult Chinese persons. Population-based cross-sectional study. Chinese adults aged 30+ years who were residents of Handan, North China. The Handan Eye Study is a population-based study of eye disease in Chinese persons. Eligible residents underwent a comprehensive ophthalmic examination including OCT (Stratus OCT, Carl Zeiss Meditec Inc., Jena, Germany). Fast macular thickness scans were performed over maculae within 6 mm in diameter, divided into 3 regions (central, inner, and outer, with a diameter of 1, 3, and 6 mm, respectively) and 9 quadrants (1 in the central region and 4 each in the inner and outer regions). Retinal thickness (means and standard deviations) was calculated by OCT mapping software, presented for foveal minimum, central macula (within 1 mm diameter), and inner and outer regions divided by 8 quadrants. Macular thickness measured by OCT. Of the 6830 participants (90.4% response rate) examined, 2230 eyes of healthy subjects with high-quality OCT scans were selected (32.7% of participants; mean age, 46.4+/-9.9 years, 58.4% were women). The mean foveal minimum, central, inner, and outer macular thicknesses were 150.3 (18.1) microm, 176.4 (17.5) microm, 255.3 (14.9) microm, and 237.7 (12.4) microm, respectively (overall differences, Pregion, the nasal quadrant was thinner than the superior and inferior quadrants, and in the outer region, the nasal quadrant was the thickest (Pmeasurements using OCT in a large population-based sample of adult Chinese persons aged 30 to 85 years were generally thinner in the foveal and central macular areas than measurements reported in other populations. Age and axial length were positively correlated with macular thickness. Copyright 2010 American Academy of Ophthalmology. Published by Elsevier Inc. All rights reserved.

  14. Continuous Auditory Feedback of Eye Movements: An Exploratory Study toward Improving Oculomotor Control

    Directory of Open Access Journals (Sweden)

    Eric O. Boyer

    2017-04-01

    Full Text Available As eye movements are mostly automatic and overtly generated to attain visual goals, individuals have a poor metacognitive knowledge of their own eye movements. We present an exploratory study on the effects of real-time continuous auditory feedback generated by eye movements. We considered both a tracking task and a production task where smooth pursuit eye movements (SPEM can be endogenously generated. In particular, we used a visual paradigm which enables to generate and control SPEM in the absence of a moving visual target. We investigated whether real-time auditory feedback of eye movement dynamics might improve learning in both tasks, through a training protocol over 8 days. The results indicate that real-time sonification of eye movements can actually modify the oculomotor behavior, and reinforce intrinsic oculomotor perception. Nevertheless, large inter-individual differences were observed preventing us from reaching a strong conclusion on sensorimotor learning improvements.

  15. A Study of the Possible Distinction Between "Controlling Eye" and "Dominant Eye" and the Effect of Both, with Hand Dominance, on Reading Achievement.

    Science.gov (United States)

    Boos, Robert W.; Hillerich, Robert L.

    This longitudinal study was a replication of two disparate studies, one of dominance and one of control, which had as subjects 277 seventh- and eighth-grade pupils remaining from an original dominance study of over 500. Eye dominance was determined through hole-in-paper and V-scope; eye control at near and far point, through the telebinocular;…

  16. Water Ice and Dust in the Innermost Coma of Comet 103P/Hartley 2

    CERN Document Server

    Protopapa, Silvia; Feaga, Lori M; Kelley, Michael S P; Hearn, Michael F A'; Farnham, Tony L; Groussin, Olivier; Besse, Sebastien; Merlin, Frederic; Li, Jian-Yang

    2014-01-01

    On November 4th, 2010, the Deep Impact eXtended Investigation (DIXI) successfully encountered comet 103P/Hartley 2, when it was at a heliocentric distance of 1.06 AU. Spatially resolved near-IR spectra of comet Hartley 2 were acquired in the 1.05-4.83 micron wavelength range using the HRI-IR spectrometer. We present spectral maps of the inner ~10 kilometers of the coma collected 7 minutes and 23 minutes after closest approach. The extracted reflectance spectra include well-defined absorption bands near 1.5, 2.0, and 3.0 micron consistent in position, bandwidth, and shape with the presence of water ice grains. Using Hapke's radiative transfer model, we characterize the type of mixing (areal vs. intimate), relative abundance, grain size, and spatial distribution of water ice and refractories. Our modeling suggests that the dust, which dominates the innermost coma of Hartley 2 and is at a temperature of 300K, is thermally and physically decoupled from the fine-grained water ice particles, which are on the order ...

  17. Use of Cognitive and Metacognitive Strategies in Online Search: An Eye-Tracking Study

    Science.gov (United States)

    Zhou, Mingming; Ren, Jing

    2016-01-01

    This study used eye-tracking technology to track students' eye movements while searching information on the web. The research question guiding this study was "Do students with different search performance levels have different visual attention distributions while searching information online? If yes, what are the patterns for high and low…

  18. Mobile eye-tracking methods in studies of audience learning in health promotion exhibitions

    DEFF Research Database (Denmark)

    Magnussen, Rikke; Zachariassen, Maria; Kharlamov, Nikita

    2017-01-01

    This paper presents a methodological discussion of the potential and challenges of involving mobile eye-tracking technology in studies of knowledge generation and learning in a science centre context. The methodological exploration is based on eye-tracking studies of audience interaction...

  19. Eye movement desensitization in fibromyalgia: a pilot study.

    Science.gov (United States)

    Friedberg, Fred

    2004-11-01

    The purpose of this study was to investigate the effectiveness of eye movement desensitization (EMD) for the relief of pain, fatigue and anxiety and depression in fibromyalgia patients. Six Caucasian female patients (mean age=43.2 yr) participated in two treatment sessions. Outcome assessments included the Fibromyalgia Impact Questionnaire, Fatigue Scale, Beck Anxiety Inventory, and Beck Depression Inventory. In-session process measures included thermal biofeedback monitoring and subjective units of discomfort ratings of pain, stress, and fatigue. Four out of six subjects were considered treatment responders. Thermal biofeedback monitoring revealed an average increase in hand temperature of 5.4 degrees indicating a relaxation effect. At treatment termination, average scores decreased on the measures of anxiety (28.6%), depression (29.9%), fibromyalgia impact (12.6%), and fatigue (11.5%). At the 3-month follow-up assessment, total reductions in average scores from pre-treatment baseline reflected further improvements on measures of anxiety (45.8%), depression (31.6%), fibromyalgia impact (19.2%), and fatigue (26.7%). Because EMD produced a somewhat automatic relaxation response with minimal patient participation, it may be especially useful when standard relaxation techniques fail.

  20. Progression of diabetic retinopathy: the Beijing Eye Study

    Institute of Scientific and Technical Information of China (English)

    TU Ying; XU Liang; WEI Wen-bin; WANG Shuang; WANG Ya-xing; Jost B Jonas

    2011-01-01

    Background Diabetic retinopathy (DR) has emerged as a leading cause of visual impairment and blindness in the working-aged population worldwide.This study aimed to assess frequency and associated factors of progression of DR in subjects with known diabetes in a population-based setting.Methods The Beijing Eye Study is a population based study performed in Greater Beijing in 2001 and 2006.The present investigation included all subjects with known diabetes mellitus in 2001,who participated in the follow-up examination in 2006.Fundus photographs were assessed.Results The study included 170 subjects; 51 (30%) subjects showed signs of DR in 2001 and were re-examined in 2006,36 (21.2%) subjects (18 subjects with DR present at baseline,18 subjects with newly diagnosed DR in 2006)showed a progression of DR during follow-up.Progression of DR was associated with rural region (odds ratio (OR):5.43,P=0.001) and self-reported arterial hypertension (OR:3.85,P=0.023).In the non-progressive subgroup,presence of DR was associated with different levels of education (<middle school,middle school,college or higher,OR:0.30,P=0.023),treatment modes of diabetes mellitus (OR:10.24,P=0.003) and cataract surgery (OR:9.14,P=0.007).Conclusions In a population-based setting in Greater Beijing,progression of DR occurred in 35% of subjects with pre-existing DR and overall in 21% of subjects with known diabetes within a 5-year period.Progression of DR was significantly associated with rural region and self-reported arterial hypertension.In the stable subjects,presence of DR was significantly associated with poor educational level,insulin treatment of diabetes and cataract surgery.

  1. Dry Eye

    Science.gov (United States)

    ... Eye > Facts About Dry Eye Facts About Dry Eye This information was developed by the National Eye ... the best person to answer specific questions. Dry Eye Defined What is dry eye? Dry eye occurs ...

  2. Eye Allergies

    Science.gov (United States)

    ... Español Eye Health / Eye Health A-Z Eye Allergies Sections What Are Eye Allergies? Eye Allergy Symptoms ... allergy diagnosis Eye allergy treatment What Are Eye Allergies? Written by: David Turbert Reviewed by: Brenda Pagan- ...

  3. A case study of blast eye injury at work place

    Directory of Open Access Journals (Sweden)

    Prabhakar Srinivasapuram Krishnacharya

    2013-12-01

    Full Text Available This case report aims at investigating whether two consecutive surgical settings would be beneficial in achieving postoperative success for the patient with blast eye injury. A 45-year-old male patient admitted on 17 th October 2011 with history of blast eye injury. Right eye examination revealed central corneal laceration with incarceration of lens matter, multiple foreign bodies also seen embedded in the eyelid margins and in the left cornea. Computed ocular tomography showed a retained intraocular foreign body (IOFB in the right eye. Simultaneous corneal laceration repair and extraction of the ruptured lens performed as primary procedure under general anesthesia. Intraoperative posterior capsule loss was noticed with vitreous presentation. Anterior vitrectomy with removal of the IOFB was done. Foreign bodies were also removed from the left cornea. Penetrating keratoplasty (PK with scleral fixated intraocular lens implantation executed 4 months later as secondary procedure. Visual acuity maintained at 6/24 in 2 years follow-up. In conclusion, two consecutive surgical settings has the advantage of calculating the intra ocular lens power.

  4. Eye-tracking studie av vektoranalys på LTH

    DEFF Research Database (Denmark)

    Ögren, Magnus; Nyström, Marcus

    detaljerad inblick i hur studenterna tänkte medan de löste problemet. Vi använder modern eye-tracking teknik för att mäta hur LTH-studenters visuella uppmärksamhet fördelar sig mellan texter, matematiska formler och figurer när de löser problem inom vektoranalys. Genom att filma studenters ögonrörelser med...... en höghastighetskamera ger eye-tracking data information om var man tittar med väldigt hög spatial och temporal upplösning. Detta gör att man kan följa lösningsprocessen millisekund för millisekund från problempresentation till svar. Med eye-tracking kan man alltså skilja på process och produkt....... Vektoranalys är ett mycket visuellt ämne där matematiska formler ofta har en konkret grafisk tolkning. Detta gör vektoranalysen till ett speciellt lämpligt ämne att studera med eye-tracking teknologin, då försökspersonens byte av fokus mellan formler och figurer kan utvärderas. Vi kommer att presentera...

  5. Ecological Validity in Eye-Tracking: An Empirical Study

    Science.gov (United States)

    Spinner, Patti; Gass, Susan M.; Behney, Jennifer

    2013-01-01

    Eye-trackers are becoming increasingly widespread as a tool to investigate second language (L2) acquisition. Unfortunately, clear standards for methodology--including font size, font type, and placement of interest areas--are not yet available. Although many researchers stress the need for ecological validity--that is, the simulation of natural…

  6. Eye-tracking studie av vektoranalys på LTH

    DEFF Research Database (Denmark)

    Ögren, Magnus; Nyström, Marcus

    detaljerad inblick i hur studenterna tänkte medan de löste problemet. Vi använder modern eye-tracking teknik för att mäta hur LTH-studenters visuella uppmärksamhet fördelar sig mellan texter, matematiska formler och figurer när de löser problem inom vektoranalys. Genom att filma studenters ögonrörelser med...... en höghastighetskamera ger eye-tracking data information om var man tittar med väldigt hög spatial och temporal upplösning. Detta gör att man kan följa lösningsprocessen millisekund för millisekund från problempresentation till svar. Med eye-tracking kan man alltså skilja på process och produkt....... Vektoranalys är ett mycket visuellt ämne där matematiska formler ofta har en konkret grafisk tolkning. Detta gör vektoranalysen till ett speciellt lämpligt ämne att studera med eye-tracking teknologin, då försökspersonens byte av fokus mellan formler och figurer kan utvärderas. Vi kommer att presentera...

  7. Prevalence of second-eye cataract surgery and time interval after first-eye surgery in Iran: A clinic-based study

    Directory of Open Access Journals (Sweden)

    Marzieh Katibeh

    2013-01-01

    Conclusion: The number of cataract operations in this tertiary eye care setting increased 1.5 fold over the study period. The proportion of second-eye operations also rose from 1/4 to 1/3 during the same time.

  8. A Case-Control Study on the Oxidative Balance of 50% Autologous Serum Eye Drops

    Directory of Open Access Journals (Sweden)

    Patrícia Ioschpe Gus

    2016-01-01

    Full Text Available Importance. Autologous serum (AS eye drops are recommended for severe dry eye in patients with ocular surface disease. No description of the antioxidant balance of AS eye drops has been reported in the literature. Objective. This study sought to evaluate the total reactive antioxidant potential (TRAP and concentration of reactive oxygen species (ROS in samples of 50% AS eye drops and their correlations with the demographic characteristics and lifestyle habits of patients with ocular surface disease and healthy controls. Design. This was a case-control study with a 3-month follow-up period. Participants. 16 patients with severe dry eye disease of different etiologies and 17 healthy controls matched by age, gender, and race were included. Results. TRAP and ROS were detected at all evaluated times. There were no differences in the mean ROS (p=0.429 or TRAP (p=0.475 levels between cases and controls. No statistically significant differences in the concentrations of ROS or TRAPs were found at 0, 15, or 30 days (p for ROS = 0.087 and p for TRAP = 0.93. Neither the demographic characteristics nor the lifestyle habits were correlated with the oxidative balance of the 50% AS eye drops. Conclusions and Relevance. Both fresh and frozen 50% AS eye drops present antioxidant capacities and ROS in an apparently stable balance. Moreover, patients with ocular surface disease and normal controls produce equivalent AS eye drops in terms of oxidative properties.

  9. Risk factors for astigmatism in preschool children: the multi-ethnic pediatric eye disease and Baltimore pediatric eye disease studies.

    Science.gov (United States)

    McKean-Cowdin, Roberta; Varma, Rohit; Cotter, Susan A; Tarczy-Hornoch, Kristina; Borchert, Mark S; Lin, Jesse H; Wen, Ge; Azen, Stanley P; Torres, Mina; Tielsch, James M; Friedman, David S; Repka, Michael X; Katz, Joanne; Ibironke, Josephine; Giordano, Lydia

    2011-10-01

    To evaluate risk factors for astigmatism in a population-based sample of preschool children. Population-based cross-sectional study. Population-based samples of 9970 children ages 6 to 72 months from Los Angeles County, California, and Baltimore, Maryland. A cross-sectional study of children participating in the Multiethnic Pediatric Eye Disease Study and the Baltimore Eye Disease Study was completed. Data were obtained by clinical examination or by in-person interview. Odds ratios and 95% confidence intervals (CI) were calculated to evaluate potential associations between clinical, behavioral, or demographic factors and astigmatism. Odds ratios (ORs) for various risk factors associated with astigmatism. Participants with myopia (≤-1.0 diopters) were 4.6 times as likely to have astigmatism (95% CI, 3.56-5.96) than those without refractive error, whereas participants with hyperopia (≥+2.00 diopters) were 1.6 times as likely (95% CI, 1.39-1.94). Children 6 to materials discussed in this article. Copyright © 2011 American Academy of Ophthalmology. Published by Elsevier Inc. All rights reserved.

  10. [Studies on hyaluronic acid as dendifier in Shuanghuanglian eye-drops].

    Science.gov (United States)

    Ma, Man-ling; Liu, Lu; Sun, Shu-ying

    2005-08-01

    To study the possibility of hyaluronic acid as densifier of Shuanguangliao eye-drops. The factors related with hyaluronic acid s viscosity, such as pH-value and storing temperature, are tested in this experiment. At the same time, we checked the stimulation, stability of the densifier. There was not effect on viscosity of pH-value and storing temperature. No stimulation on the eye was found after densified with hyaluronic acid. The viscosity properties of hyaluronic acid are stablile. The hyaliuronic acid added to Shuanghuanglian eye-drops are stabiliable and it can be applied in eye-drops. The increased viscosity is benefit to extend the residence time of drug in eye.

  11. [Study of biopharmaceutic characteristics of cromoglycate eye drops].

    Science.gov (United States)

    Klimas, Rimantas; Inkeniene, Asta Marija; Briedis, Vitalis; Gerbutaviciene, Rima Jūrate

    2003-01-01

    One of the factors influencing the release of active substance from the drug formulation is presence of polymeric substance resulting in increase of viscosity of eye drops. Diffusion of sodium cromoglycate from polyvinyl alcohol 1.4%, 3% solutions and hypromellose 1% aqueous solution was investigated using in vitro method and diffusion coefficients were evaluated. Release of sodium cromoglycate from polyvinyl alcohol 1.4%, 3% solutions and hypromellose 1% aqueous solution was slower than the release from aqueous solution of sodium cromoglycate. The sodium cromoglycate diffusion from ophthalmic vehicle process kinetics was influenced by viscosity of these solutions and nature of the used polymers. The diffusion process of sodium cromoglycate from 1.4% PVA solution was more intensive if compared to diffusion from 1% hypromellose solution. The influence of excipients on sodium cromoglycate diffusion from eye drop formulation was evaluated when polymeric solutions have been used as vehicles.

  12. Long-range eye tracking: A feasibility study

    Energy Technology Data Exchange (ETDEWEB)

    Jayaweera, S.K.; Lu, Shin-yee

    1994-08-24

    The design considerations for a long-range Purkinje effects based video tracking system using current technology is presented. Past work, current experiments, and future directions are thoroughly discussed, with an emphasis on digital signal processing techniques and obstacles. It has been determined that while a robust, efficient, long-range, and non-invasive eye tracking system will be difficult to develop, such as a project is indeed feasible.

  13. Covert tracking: a combined ERP and fixational eye movement study.

    Directory of Open Access Journals (Sweden)

    Alexis D J Makin

    Full Text Available Attention can be directed to particular spatial locations, or to objects that appear at anticipated points in time. While most work has focused on spatial or temporal attention in isolation, we investigated covert tracking of smoothly moving objects, which requires continuous coordination of both. We tested two propositions about the neural and cognitive basis of this operation: first that covert tracking is a right hemisphere function, and second that pre-motor components of the oculomotor system are responsible for driving covert spatial attention during tracking. We simultaneously recorded event related potentials (ERPs and eye position while participants covertly tracked dots that moved leftward or rightward at 12 or 20°/s. ERPs were sensitive to the direction of target motion. Topographic development in the leftward motion was a mirror image of the rightward motion, suggesting that both hemispheres contribute equally to covert tracking. Small shifts in eye position were also lateralized according to the direction of target motion, implying covert activation of the oculomotor system. The data addresses two outstanding questions about the nature of visuospatial tracking. First, covert tracking is reliant upon a symmetrical frontoparietal attentional system, rather than being right lateralized. Second, this same system controls both pursuit eye movements and covert tracking.

  14. Covert tracking: a combined ERP and fixational eye movement study.

    Science.gov (United States)

    Makin, Alexis D J; Poliakoff, Ellen; Ackerley, Rochelle; El-Deredy, Wael

    2012-01-01

    Attention can be directed to particular spatial locations, or to objects that appear at anticipated points in time. While most work has focused on spatial or temporal attention in isolation, we investigated covert tracking of smoothly moving objects, which requires continuous coordination of both. We tested two propositions about the neural and cognitive basis of this operation: first that covert tracking is a right hemisphere function, and second that pre-motor components of the oculomotor system are responsible for driving covert spatial attention during tracking. We simultaneously recorded event related potentials (ERPs) and eye position while participants covertly tracked dots that moved leftward or rightward at 12 or 20°/s. ERPs were sensitive to the direction of target motion. Topographic development in the leftward motion was a mirror image of the rightward motion, suggesting that both hemispheres contribute equally to covert tracking. Small shifts in eye position were also lateralized according to the direction of target motion, implying covert activation of the oculomotor system. The data addresses two outstanding questions about the nature of visuospatial tracking. First, covert tracking is reliant upon a symmetrical frontoparietal attentional system, rather than being right lateralized. Second, this same system controls both pursuit eye movements and covert tracking.

  15. An Eye Tracking Study into the Effects of Graph Layout

    CERN Document Server

    Huang, Weidong

    2008-01-01

    Graphs are typically visualized as node-link diagrams. Although there is a fair amount of research focusing on crossing minimization to improve readability, little attention has been paid on how to handle crossings when they are an essential part of the final visualizations. This requires us to understand how people read graphs and how crossings affect reading performance. As an initial step to this end, a preliminary eye tracking experiment was conducted. The specific purpose of this experiment was to test the effects of crossing angles and geometric-path tendency on eye movements and performance. Sixteen subjects performed both path search and node locating tasks with six drawings. The results showed that small angles can slow down and trigger extra eye movements, causing delays for path search tasks, whereas crossings have little impact on node locating tasks. Geometric-path tendency indicates that a path between two nodes can become harder to follow when many branches of the path go toward the target node...

  16. Face, eye, and body selective responses in fusiform gyrus and adjacent cortex: an intracranial EEG study.

    Directory of Open Access Journals (Sweden)

    Andrew D Engell

    2014-08-01

    Full Text Available Functional MRI (fMRI studies have investigated the degree to which processing of whole faces, face-parts, and bodies are differentially localized within the fusiform gyrus and adjacent ventral occipitotemporal cortex. While some studies have emphasized the spatial differentiation of processing into discrete areas, others have emphasized the overlap of processing and the importance of distributed patterns of activity. Intracranial EEG (iEEG recorded from subdural electrodes provides excellent temporal and spatial resolution of local neural activity, and thus provides an alternative method to fMRI for studying differences and commonalities in face and body processing. In this study we recorded iEEG from 12 patients while they viewed images of novel faces, isolated eyes, headless bodies, and flowers. ERP analysis identified 69 occipitotemporal sites at which there was a face-, eye-, or body-selective response when contrasted to flowers. However, when comparing faces, eyes, and bodies to each other at these sites, we identified only 3 face-specific, 13 eye-specific, and 1 body-specific electrodes. Thus, at the majority of sites, faces, eyes, and bodies evoked similar responses. However, we identified ten locations at which the amplitude of the responses spatially varied across adjacent electrodes, indicating that the configuration of current sources and sinks were different for faces, eyes, and bodies. Our results also demonstrate that eye-sensitive regions are more abundant and more purely selective than face- or body-sensitive regions, particularly in lateral occipitotemporal cortex.

  17. Face, eye, and body selective responses in fusiform gyrus and adjacent cortex: an intracranial EEG study.

    Science.gov (United States)

    Engell, Andrew D; McCarthy, Gregory

    2014-01-01

    Functional MRI (fMRI) studies have investigated the degree to which processing of whole faces, face-parts, and bodies are differentially localized within the fusiform gyrus and adjacent ventral occipitotemporal cortex. While some studies have emphasized the spatial differentiation of processing into discrete areas, others have emphasized the overlap of processing and the importance of distributed patterns of activity. Intracranial EEG (iEEG) recorded from subdural electrodes provides excellent temporal and spatial resolution of local neural activity, and thus provides an alternative method to fMRI for studying differences and commonalities in face and body processing. In this study we recorded iEEG from 12 patients while they viewed images of novel faces, isolated eyes, headless bodies, and flowers. Event-related potential analysis identified 69 occipitotemporal sites at which there was a face-, eye-, or body-selective response when contrasted to flowers. However, when comparing faces, eyes, and bodies to each other at these sites, we identified only 3 face-specific, 13 eye-specific, and 1 body-specific electrodes. Thus, at the majority of sites, faces, eyes, and bodies evoked similar responses. However, we identified ten locations at which the amplitude of the responses spatially varied across adjacent electrodes, indicating that the configuration of current sources and sinks were different for faces, eyes, and bodies. Our results also demonstrate that eye-sensitive regions are more abundant and more purely selective than face- or body-sensitive regions, particularly in lateral occipitotemporal cortex.

  18. A comparative clinical study of Solcoseryl Eye-Gel and Cysteine Eye-Gel 2.4% in the treatment of foreign-body injuries of the cornea.

    Science.gov (United States)

    Studer, O

    1984-01-01

    Solcoseryl, a protein-free haemodialysate, promotes tissue regeneration and improves utilization of oxygen in the cell. In a randomized, double-blind, clinical study, Solcoseryl Eye-Gel was compared with Cysteine Eye-Gel in the treatment of foreign-body injuries of the cornea in a total of 99 eyes. In order to facilitate objective evaluation of the effects of the treatment, the area of the lesion before the start of treatment and on the following day was determined by means of slit-lamp photographs. Healing of the lesion and relative reduction of the area of the wound were observed much more frequently in the group treated with Solcoseryl Eye-Gel than in the reference group. Maculae corneae after the end of the treatment were significantly less frequent under Solcoseryl Eye-Gel than under Cysteine Eye-Gel. Teh tolerability of the test preparation was good; an itching sensation was reported in only 2 cases. Under Cysteine Eye-Gel, on the other hand, a burning sensation was reported by a number of patients and very fine deposits in the epithelium were also observed in a few cases. Thus complete closure of the epithelium over the lesion after 1 day was observed much more frequently in the group of patients treated with Solcoseryl Eye-Gel than in the reference group (63 vs. 53%).

  19. A Study on Hospital Admissions For Eye Trauma in Kashan, Iran

    Directory of Open Access Journals (Sweden)

    Movahedinejad

    2016-05-01

    Full Text Available Background Eye trauma is among the most common reasons for referral to hospital emergency departments and ophthalmologists’ offices. It also is a common cause of vision loss worldwide. However, few studies are available on the changes in the epidemiology of eye trauma in Iran in recent years. Objectives This study aimed to investigate the characteristics of hospital admissions for eye trauma in Kashan from August 2011 to February 2014. Patients and Methods A cross-sectional study was carried out on the hospital records of all patients with eye trauma who were admitted to Kashan’s Matini hospital between August 2011 and February 2014. Having an eye trauma and being hospitalized for at least one day was selected as the criteria for inclusion in the study. The data were then recorded on a checklist devised by the researcher. After entering the data into the SPSS software, descriptive statistics (i.e., percentage, frequency, mean, and standard deviation were calculated for all variables. Chi-square, Fisher’s exact test, and Mann-Whitney U test were used to analyze the data. Results In total, 200 patients with eye trauma had been hospitalized in Matini Hospital between August 2011 and February 2014. Of these patients, 86% were males, 40% were in the age range of 20-39 years, 68% lived in urban areas, and 21% of those in employment were manual and industrial workers. Approximately 38.5% of eye traumas had occurred in the work place; 72.5% of patients had penetrating injuries and 98% of cases were injured in one eye. More injuries occurred in the cornea (25.5% than elsewhere in the eye, and 75.5% of patients were treated surgically. Among all variables, only the type of trauma (P = 0.009 and cause of trauma (P = 0.004 were significantly related to the patients’ gender. Conclusions Eye trauma was prevalent among males, young people, urban residents, and manual and industrial workers. As the eyes play a vital role in daily life, communication

  20. Outcomes of cataract surgery in urban southern China: the Liwan Eye Study.

    Science.gov (United States)

    Huang, Wenyong; Huang, Guofu; Wang, Dandan; Yin, Qiuxia; Foster, Paul J; He, Mingguang

    2011-01-01

    The outcomes of cataract surgery have been well reported in rural China; however, the situation in the urban population remains unclear. This study assessed the outcomes of cataract surgery in urban southern China. Data were gathered from the Liwan Eye Study, a population-based, cross-sectional study conducted in people aged 50 years or more in the Liwan District of Guangzhou. Presenting and best corrected visual acuity and a detailed eye examination were performed. For all aphakic and pseudophakic participants identified, information on the date, setting, type, and complications of cataract surgery were recorded. Of the 1405 participants, 62 people (90 eyes) had undergone cataract surgery. Of those, 54.4% underwent the phacoemulsification (Phaco) technique, 33.3% extracapsular cataract extraction (ECCE) with intraocular lens (IOL) implantation, and 11.1% ECCE without IOL; 1 patient had intracapsular cataract extraction (ICCE). Presenting visual acuity (PVA) was >6/18 in 56 (62.2%) eyes, 6/60 in 20 (22.2%) eyes, 3/60 in 3 (3.3%) eyes, and ECCE or Phaco with IOL are the major surgical techniques used in urban southern China. More than half of the eyes with poor outcomes due to uncorrected aphakia, refractive error, or PCO are potentially treatable. This result suggests a pressing need for improved surgical training and postoperative care.

  1. Chemical composition of Melicope belahe (Baill.) T. G. Hartley (Rutaceae) leaf essential oil from Madagascar.

    Science.gov (United States)

    Rabehaja, Delphin J R; Garcia, Gabriel; Charmillon, Julie-Marie; Désiré, Odile; Paoli, Mathieu; Ramanoelina, Panja A R; Tomi, Félix

    2017-01-01

    Melicope belahe (Baill.) T.G. Hartley (Rutaceae) is an endemic species to Madagascar. The chemical composition of leaf essential oil is reported for the first time. A sample was extracted by hydrodistillation and analysis was carried out by combination of chromatographic (GC), spectroscopic and spectrometric (MS, (13)C NMR) techniques. In total, 56 compounds have been identified. The chemical composition was dominated by α-pinene (42.6%) followed by linalool (6.2%) and (E)-β-caryophyllene (5.2%).

  2. Spitzer Space Telescope Observations of the Nucleus of Comet 103P/Hartley 2

    Science.gov (United States)

    Lisse, C. M.; Fernandez, Y. R.; Reach, W. T.; Bauer, J. M.; A’Hearn, M. F.; Farnham, T. L.; Groussin, O.; Belton, M. J.; Meech, K. J.; Snodgrass, C. D.

    2009-09-01

    We have used the Spitzer Space Telescope InfraRed Spectrograph (IRS) 22-μm peakup array to observe thermal emission from the nucleus and trail of comet 103P/Hartley 2, the target of NASA’s Deep Impact Extended Investigation (DIXI). The comet was observed on UT 2008 August 12 and 13, while 5.5 AU from the Sun. We obtained two 200 frame sets of photometric imaging over a 2.7 hr period. To within the errors of the measurement, we find no detection of any temporal variation between the two images. The comet showed extended emission beyond a point source in the form of a faint trail directed along the comet’s antivelocity vector. After modeling and removing the trail emission, a NEATM model for the nuclear emission with beaming parameter of 0.95 ± 0.20 indicates a small effective radius for the nucleus of 0.57 ± 0.08 km and low geometric albedo 0.028 ± 0.009 (1σ). With this nucleus size and a water production rate of 3 × 1028 molecules s-1 at perihelion, we estimate that ∼100% of the surface area is actively emitting volatile material at perihelion. Reports of emission activity out to ∼5 AU support our finding of a highly active nuclear surface. Compared to Deep Impact’s first target, comet 9P/Tempel 1, Hartley 2’s nucleus is one-fifth as wide (and about one-hundredth the mass) while producing a similar amount of outgassing at perihelion with about 13 times the active surface fraction. Unlike Tempel 1, comet Hartley 2 should be highly susceptible to jet driven spin-up torques, and so could be rotating at a much higher frequency. Since the amplitude of nongravitational forces are surprisingly similar for both comets, close to the ensemble average for ecliptic comets, we conclude that comet Hartley 2 must have a much more isotropic pattern of time-averaged outgassing from its nuclear surface. Barring a catastrophic breakup or major fragmentation event, the comet should be able to survive up to another 100 apparitions (∼700 yr) at its current rate of

  3. Picture perception in Chinese dyslexic children: an eye-movement study

    Institute of Scientific and Technical Information of China (English)

    LI Xiu-hong; JING Jin; ZOU Xiao-bing; HUANG Xu; JIN Yu; WANG Qing-xiong; CHEN Xue-bin; YANG Bin-rang; YANG Si-yuan

    2009-01-01

    Background Currently, whether or not there is visuospatial impairments in Chinese dyslexic children is still a matter of discussion. The relatively recent application of an eye-tracking paradigm may offer an opportunity to address this issue. In China, in comparison with reading studies, there have not been nearly as many eye movement studies dealing with nonreading tasks such as picture identification and whether Chinese children with dyslexia have a picture processing deficit is not clear. The purposes of the present study were to determine whether or not there is visuospatial impairments in Chinese dyslexic children. Moreover, we attempted to discuss whether or not the abnormal eye movement pattern that dyslexic subjects show during reading of text appropriate for their age is a consequence of their linguistic difficulties.Methods An eye-link Ⅱ High-Speed Eye Tracker was used to track the series of eye-movement of 19 Chinese dyslexic children and 19 Chinese normal children. All of the subjects were presented with three pictures for this eye-tracking task and 6 relative eye-movement parameters, first fixation duration, average fixation duration, average saccade amplitude, mean saccade distance, fixation frequency and saccade frequency were recorded for analysis.Results Analyzing the relative parameter among three pictures, except for the fixation frequency and the saccade frequency, other eye-movement parameters were significantly different among the three pictures (P 0.05).Conclusions The characteristics of the pictures can significantly influence the visuospatial cognitive processing capability of the Chinese children. There is a detectable disability for the Chinese dyslexic children in the visuospatial cognitive processing: their saccade amplitude and mean saccade distance are shorter, which may be interpreted as specific for their reading disability.

  4. Many Kids with Diabetes Missing Out on Eye Exams, Study Finds

    Science.gov (United States)

    ... news/fullstory_164258.html Many Kids With Diabetes Missing Out on Eye Exams, Study Finds Those with ... that children and teens with diabetes from poor families and those from racial/ethnic minorities were less ...

  5. Study on chromatic aberration in a population of Chinese myopic eyes by means of optical design.

    Science.gov (United States)

    He, Yuanqing; Wang, Yan; Wang, Zhaoqi; Fang, Chao; Liu, Yongji; Zhang, Lin; Zheng, Shaolin; Wang, Lu; Chang, Shengjiang

    2013-05-01

    Two kinds of individual eye models, involving and without involving the angle between visual axis and optical axis, are established by means of optical design. We use them to study the properties of the transverse chromatic aberration (TCA) and longitudinal chromatic aberration (LCA) over the visible spectrum. Then the effects of the LCA and TCA on the visual quality of human eyes are evaluated. The statistical averages of TCA and LCA over the visible spectrum for Chinese myopic eyes are obtained. Results show that both TCA and LCA restrict the visual performance, and LCA is more detrimental than TCA.

  6. Anti-inflammatory and Antihistaminic Study of a Unani Eye Drop Formulation

    Directory of Open Access Journals (Sweden)

    Latif Abdul

    2010-03-01

    Full Text Available The Unani eye drop is an ophthalmic formulation prepared for its beneficial effects in the inflammatory and allergic conditions of the eyes. In the present study, the Unani eye drop formulation was prepared and investigated for its anti-inflammatory and antihistaminic activity, using in vivo and in vitro experimental models respectively. The Unani eye drop formulation exhibited significant anti-inflammatory activity in turpentine liniment-induced ocular inflammation in rabbits. The preparation also showed antihistaminic activity in isolated guinea-pig ileum. The anti-inflammatory and antihistaminic activity of eye drop may be due to presence of active ingredients in the formulation. Although there are many drugs in Unani repository which are mentioned in classical books or used in Unani clinical practice effectively in treatment of eye diseases by various Unani physicians. Inspite of the availability of vast literature, there is a dearth of commercial Unani ocular preparations. So, keeping this in mind, the eye drop formulation was prepared and its anti-inflammatory and antihistaminic activity was carried out in animal models. Thus, in view of the importance of alternative anti-inflammatory and anti- allergic drugs, it becomes imperative to bring these indigenous drugs to the front foot and evaluate their activities.

  7. Intermediate photofragment distributions as probes of non-adiabatic dynamics at conical intersections: application to the Hartley band of ozone.

    Science.gov (United States)

    Picconi, David; Grebenshchikov, Sergy Yu

    2015-11-21

    Quantum dynamics at a reactive two-state conical intersection lying outside the Franck-Condon zone is studied for a prototypical reaction of ultraviolet photodissociation of ozone in the Hartley band. The focus is on the vibrational distributions in the two electronic states at intermediate interfragment distances near the intersection. Such intermediate distributions of strongly interacting photofragments contain unique information on the location and shape of the conical intersection. Multidimensional Landau-Zener modeling provides a framework to reverse engineer the molecular geometry-dependent Massey parameter of the intersection from the intermediate distributions. The conceptual approach is demonstrated for the intermediate O-O bond stretch distributions which become strongly inverted on adiabatic passage through the intersection. It is further demonstrated that intermediate distributions can be reconstructed from the photoemission spectrum of the dissociating molecule. The illustration, given using quantum mechanical calculations of resonance Raman profiles for ozone, completes a practicable cycle of conversion of intermediate distributions into topographic features of the conical intersection.

  8. Prevalence of dry eye syndrome at patients with diabetus melitus tip 2, one year retrospective study May 2011-June 2012

    Directory of Open Access Journals (Sweden)

    Nora Burda

    2012-01-01

    Conclusions: In our study the Dry Eye Syndrome showed to have a high correlation with Diabetes Mellitus Tip II (about 52.9%. Prevalence of Dry Eye was significantly higher at patients with longer duration of diabetes. Dry Eye seems to be an important contributing factor related to corneal abnormalities. Age and sex not seem to play any important role in this condition. Good glycemic control is important for prevention and control of Dry Eye Syndrome.

  9. Long-Term Monitoring of Comet 103P/Hartley 2

    CERN Document Server

    Lin, Zhong-Yi; Ip, Wing-Huen

    2013-01-01

    We reported the monitoring results on spectrophotometry, photometry and imaging of comet 103P/Hartley 2 obtained at Lulin (1m), Calar Alto (2.2m) and Beijing Astronomical (2.16m) Observatory from April to December 2010. We found that a dust feature at sunward direction was detected starting from the end of September until the beginning of December (our last observation from the Lulin and Calar Alto observatory). Two distinct sunward jet features in the processed images were observed on October 11 and after October 29 until November 2. In parallel, the CN images reveal two asymmetrical jet features which are nearly perpendicular to the Sun-nucleus direction and this asymmetrical features implies that the comet was in a nearly side-on view in late-October and early-November. Additional to the jet features, the average result of the C2-to-CN production rate ratio ranges from 0.7 to 1.5 which places 103P/Hartley 2 as being of typical cometary chemistry. We found that the $r_h$ dependence for the dust production r...

  10. TU-E-201-02: Eye Lens Dosimetry From CT Perfusion Studies

    Energy Technology Data Exchange (ETDEWEB)

    Zhang, D. [Toshiba America Medical Systems (United States)

    2015-06-15

    Madan M. Rehani, Massachusetts General Hospital and Harvard Medical School, Boston Methods for Eye Lens Dosimetry and Studies On Lens Opacities with Interventionalists Radiation induced cataract is a major threat among staff working in interventional suites. Nearly 16 million interventional procedures are performed annually in USA. Recent studies by the principal investigator’s group, primarily among interventional cardiologists, on behalf of the International Atomic Energy Agency, show posterior subcapsular (PSC) changes in the eye lens in 38–53% of main operators and 21–45% of support staff. These changes have potential to lead to cataract in future years, as per information from A-Bomb survivors. The International Commission on Radiological Protection has reduced dose limit for staff by a factor of 7.5 (from 150 mSv/y to 20 mSv/y). With increasing emphasis on radiation induced cataracts and reduction in threshold dose for eye lens, there is a need to implement strategies for estimating eye lens dose. Unfortunately eye lens dosimetry is at infancy when it comes to routine application. Various approaches are being tried namely direct measurement using active or passive dosimeters kept close to eyes, retrospective estimations and lastly correlating patient dose in interventional procedures with staff eye dose. The talk will review all approaches available and ongoing active research in this area, as well as data from surveys done in Europe on status of eye dose monitoring in interventional radiology and nuclear medicine. The talk will provide update on how good is Hp(10) against Hp(3), estimations from CTDI values, Monte Carlo based simulations and current status of eye lens dosimetry in USA and Europe. The cataract risk among patients is in CT examinations of the head. Since radiation induced cataract predominantly occurs in posterior sub-capsular (PSC) region and is thus distinguishable from age or drug related cataracts and is also preventable, actions on

  11. The eye of Drosophila as a model system for studying intracellular signaling in ontogenesis and pathogenesis.

    Science.gov (United States)

    Katanaev, V L; Kryuchkov, M V

    2011-12-01

    Many human diseases are caused by malfunction of basic types of cellular activity such as proliferation, differentiation, apoptosis, cell polarization, and migration. In turn, these processes are associated with different routes of intracellular signal transduction. A number of model systems have been designed to study normal and abnormal cellular and molecular processes associated with pathogenesis. The developing eye of the fruit fly Drosophila melanogaster is one of these systems. The sequential development of compound eyes of this insect makes it possible to model human neurodegenerative diseases and mechanisms of carcinogenesis. In this paper we overview the program of the eye development in Drosophila, with emphasis on intracellular signaling pathways that regulate this complex process. We discuss in detail the roles of the Notch, Hedgehog, TGFβ, Wnt, and receptor tyrosine kinase signaling pathways in Drosophila eye development and human pathology. We also briefly describe the modern methods of experimentation with this model organism to analyze the function of human pathogenic proteins.

  12. The Experimental Study of Safety and Efficacy in Using Bovis Calculus Pharmacopuncture Solution as Eye Drop

    Directory of Open Access Journals (Sweden)

    Hyeongsik Seo

    2009-09-01

    Full Text Available Objectives : This experimental study was performed to investigate the safety and efficacy of Bovis Calculus pharmacopuncture solution manufactured with freezing dryness method to use eye drop. To identify the use of it as eye drop, the eye irritation test of rabbits and the antibacterial test of Staphylococcus aureus, Staphylococcus epidermidis, Pseudomonas aeruginosa, Aspergillus niger, Fusarium oxysporum, and Candida albicans were performed. Methods : 1. The eye irritation test of this material was performed according to the Regulation of Korea Food & Drug Administration(2005. 10. 21, KFDA 2005-60. After Bovis Calculus pharmacopuncture solution was administered in the left eye of the rabbits, eye irritation of the cornea, iris and conjunctiva was observed at 1, 2, 3, 4 & 7day. 2. After administering Bovis Calculus pharmacopuncture solution on bacterial species(Staphylococcus aureus, Staphylococcus epidermidis, Pseudomonas aeruginosa, Aspergillus niger, Fusarium oxysporum, Candida albicans which cause Keratitis, MIC(Minimum Inhibition Concentration and the size of inhibition zone were measured. Anti-bacterial potency was also measured using the size of inhibition zone. Results : 1. After Bovis Calculus pharmacopuncture solution was administered in the left eye of the rabbits, it was found that none of nine rabbits have abnormal signs and weight changes. 2. After Bovis Calculus pharmacopuncture solution was medicated in the left eye of the rabbits, no eye irritation of the cornea, iris and conjunctiva was observed at 1, 2, 3, 4 & 7day. 3. There was no response to MIC on bacterial species (Staphylococcus aureus, Staphylococcus epidermidis, Pseudomonas aeruginosa, Aspergillus niger, Fusarium oxysporum, Candida albicans after Bovis Calculus pharmacopuncture solution was medicated. Conclusions : The present study suggests that Bovis Calculus pharmacopuncture solution is a nontoxic and non-irritant medicine, which does not cause eye irritation in

  13. Impact of Visual Impairment and Eye diseases on Mortality: the Singapore Malay Eye Study (SiMES).

    Science.gov (United States)

    Siantar, Rosalynn Grace; Cheng, Ching-Yu; Gemmy Cheung, Chui Ming; Lamoureux, Ecosse L; Ong, Peng Guan; Chow, Khuan Yew; Mitchell, Paul; Aung, Tin; Wong, Tien-Yin; Cheung, Carol Y

    2015-11-09

    We investigated the relationship of visual impairment (VI) and age-related eye diseases with mortality in a prospective, population-based cohort study of 3,280 Malay adults aged 40-80 years between 2004-2006. Participants underwent a full ophthalmic examination and standardized lens and fundus photographic grading. Visual acuity was measured using logMAR chart. VI was defined as presenting (PVA) and best-corrected (BCVA) visual acuity worse than 0.30 logMAR in the better-seeing eye. Participants were linked with mortality records until 2012. During follow-up (median 7.24 years), 398 (12.2%) persons died. In Cox proportional-hazards models adjusting for relevant factors, participants with VI (PVA) had higher all-cause mortality (hazard ratio[HR], 1.57; 95% confidence interval[CI], 1.25-1.96) and cardiovascular (CVD) mortality (HR 1.75; 95% CI, 1.24-2.49) than participants without. Diabetic retinopathy (DR) was associated with increased all-cause (HR 1.70; 95% CI, 1.25-2.36) and CVD mortality (HR 1.57; 95% CI, 1.05-2.43). Retinal vein occlusion (RVO) was associated with increased CVD mortality (HR 3.14; 95% CI, 1.26-7.73). No significant associations were observed between cataract, glaucoma and age-related macular degeneration with mortality. We conclude that persons with VI were more likely to die than persons without. DR and RVO are markers of CVD mortality.

  14. Impact of Visual Impairment and Eye diseases on Mortality: the Singapore Malay Eye Study (SiMES)

    Science.gov (United States)

    Siantar, Rosalynn Grace; Cheng, Ching-Yu; Gemmy Cheung, Chui Ming; Lamoureux, Ecosse L.; Ong, Peng Guan; Chow, Khuan Yew; Mitchell, Paul; Aung, Tin; Wong, Tien-Yin; Cheung, Carol Y.

    2015-01-01

    We investigated the relationship of visual impairment (VI) and age-related eye diseases with mortality in a prospective, population-based cohort study of 3,280 Malay adults aged 40–80 years between 2004–2006. Participants underwent a full ophthalmic examination and standardized lens and fundus photographic grading. Visual acuity was measured using logMAR chart. VI was defined as presenting (PVA) and best-corrected (BCVA) visual acuity worse than 0.30 logMAR in the better-seeing eye. Participants were linked with mortality records until 2012. During follow-up (median 7.24 years), 398 (12.2%) persons died. In Cox proportional-hazards models adjusting for relevant factors, participants with VI (PVA) had higher all-cause mortality (hazard ratio[HR], 1.57; 95% confidence interval[CI], 1.25–1.96) and cardiovascular (CVD) mortality (HR 1.75; 95% CI, 1.24–2.49) than participants without. Diabetic retinopathy (DR) was associated with increased all-cause (HR 1.70; 95% CI, 1.25–2.36) and CVD mortality (HR 1.57; 95% CI, 1.05–2.43). Retinal vein occlusion (RVO) was associated with increased CVD mortality (HR 3.14; 95% CI, 1.26–7.73). No significant associations were observed between cataract, glaucoma and age-related macular degeneration with mortality. We conclude that persons with VI were more likely to die than persons without. DR and RVO are markers of CVD mortality. PMID:26549406

  15. Missing X and Y: a review of participant ages in population-based eye studies.

    Science.gov (United States)

    Forward, Hannah; Hewitt, Alex W; Mackey, David A

    2012-04-01

    Ophthalmic population-based studies have been used to establish the frequency of eye disease and the associated environmental and genetic factors that cause vision impairment and blindness. Most of these studies have concentrated on the diseases of ageing: cataract, age-related macular degeneration, glaucoma and diabetic retinopathy. Other studies have identified eye diseases in children but few studies of young adult eye disease exist. We conducted a systematic review of the ophthalmic literature to identify potential population-based eye studies and then note the age of participants in the studies. We then summarized the disease specific to young adults to show there is a need for further research to identify eye disease in this important and often-neglected group in the community. Eighty-four large population-based studies have been conducted worldwide: 9 in North America, 2 in South America, 17 in Africa, 35 in Asia, 11 in Australia and the Pacific, 6 in Europe, 4 in the Middle East and 1 that covered 3 continents. No studies specifically examined young adults. Twenty-six per cent of studies included young adults as part of all ages examined but none of these examined a large number of young adults.

  16. Eye redness

    Science.gov (United States)

    Bloodshot eyes; Red eyes; Scleral injection; Conjunctival injection ... There are many causes of a red eye or eyes. Some are medical emergencies. Others are a cause for concern, but not an emergency. Many are nothing to worry about. Eye ...

  17. Radiation protection to the eye and thyroid during diagnostic cerebral angiography: a phantom study.

    LENUS (Irish Health Repository)

    Shortt, C P

    2008-08-01

    We measured radiation doses to the eye and thyroid during diagnostic cerebral angiography to assess the effectiveness of bismuth and lead shields at dose reduction. Phantom head angiographic studies were performed with bismuth (study 1) and lead shields (study 2). In study 1 (12 phantoms), thermoluminescent dosimeters (TLD) were placed over the eyes and thyroid in three groups: (i) no shields (four phantoms); (ii) anterior bismuth shields (four phantoms) and (iii) anterior and posterior bismuth shields (four phantoms). In a second study (eight phantoms), lead shields were placed over the thyroid only and TLD dose measurements obtained in two groups: (i) no shielding (four phantoms) and (ii) thyroid lead shielding (four phantoms). A standard 4-vessel cerebral angiogram was performed on each phantom. Study 1 (bismuth shields) showed higher doses to the eyes compared with thyroid (mean 13.03 vs 5.98 mSv, P < 0.001) and a higher eye dose on the X-ray tube side. Overall, the use of bismuth shielding did not significantly reduce dose to either eyes or thyroid in the measured TLD positions. In study 2, a significant thyroid dose reduction was found with the use of lead shields (47%, mean 2.46 vs 4.62 mSv, P < 0.001). Considerable doses to the eyes and thyroid highlight the need for increased awareness of patient protection. Eye shielding is impractical and interferes with diagnostic capability. Thyroid lead shielding yields significant protection to the thyroid, is not in the field of view and should be used routinely.

  18. Rotationally Induced Surface Slope-Instabilities and the Activation of CO2 Activity on Comet 103P/Hartley 2

    CERN Document Server

    Steckloff, Jordan K; Hirabayashi, Toshi; Melosh, H Jay; Richardson, James

    2016-01-01

    Comet 103P/Hartley 2 has diurnally controlled, CO2-driven activity on the tip of the small lobe of its bilobate nucleus. Such activity is unique among the comet nuclei visited by spacecraft, and suggests that CO2 ice is very near the surface, which is inconsistent with our expectations of an object that thermophysically evolved for ~45 million years prior to entering the Jupiter Family of comets. Here we explain this pattern of activity by showing that a very plausible recent episode of rapid rotation (rotation period of ~11 [10-13] hours) would have induced avalanches in Hartley 2's currently active regions that excavated down to CO2-rich ices and activated the small lobe of the nucleus. At Hartley 2's current rate of spindown about its principal axis, the nucleus would have been spinning fast enough to induce avalanches ~3-4 orbits prior to the DIXI flyby (~1984-1991). This coincides with Hartley 2's discovery in 1986, and implies that the initiation of CO2 activity facilitated the comet's discovery. During...

  19. Quantification of contributions of molecular fragments for eye irritation of organic chemicals using QSAR study.

    Science.gov (United States)

    Kar, Supratik; Roy, Kunal

    2014-05-01

    The eye irritation potential of chemicals has largely been evaluated using the Draize rabbit-eye test for a very long time. The Draize eye-irritation data on 38 compounds established by the European Center for Ecotoxicology and Toxicology of Chemicals (ECETOC) has been used in the present quantitative structure-activity relationship (QSAR) analysis in order to predict molar-adjusted eye scores (MES) and determine possible structural requisites and attributes that are primarily responsible for the eye irritation caused by the studied solutes. The developed model was rigorously validated internally as well as externally by applying principles of the Organization for Economic Cooperation and Development (OECD). The test for applicability domain was also carried out in order to check the reliability of the predictions. Important fragments contributing to higher MES values of the solutes were identified through critical analysis and interpretation of the developed model. Considering all the identified structural attributes, one can choose or design safe solutes with low eye irritant properties. The presented approach suggests a model for use in the context of virtual screening of relevant solute libraries. The developed QSAR model can be used to predict existing as well as future chemicals falling within the applicability domain of the model in order to reduce the use of animals.

  20. Treatment of Sjögren's syndrome dry eye using 0.03% tacrolimus eye drop: Prospective double-blind randomized study.

    Science.gov (United States)

    Moscovici, Bernardo Kaplan; Holzchuh, Ricardo; Sakassegawa-Naves, Fernando Eiji; Hoshino-Ruiz, Diego Ricardo; Albers, Marcos Bottene Villa; Santo, Ruth Miyuki; Hida, Richard Yudi

    2015-10-01

    To describe the clinical efficacy of the treatment of Sjögren's syndrome dry eye using 0.03% tacrolimus eye drop. Prospective double-blind randomized study. Institutional outpatient clinic. Forty-eight eyes of twenty-four patients with dry eye related to Sjögren syndrome were enrolled in this study. The patients were randomized in 2 groups: tacrolimus (n=14) and vehicle (n=10) group. The tacrolimus group received a vial containing tacrolimus 0.03% (almond oil as vehicle) and the other group received the almond oil vehicle. All patients were instructed to use the eye drops every 12h in the lower conjunctival sac. Schirmer I test, break-up-time (BUT), corneal fluorescein and Rose Bengal staining scores were evaluated in all patients one day before the treatment (baseline), 7, 14, 28 and 90 days after treatment with the eye drops. The average fluorescein and Rose Bengal scores improved statistically after 7 days of treatment and even more after 90 days. The average Schirmer I and BUT values were unchanged after 7, 14 and 21 days but did show an improvement relative to baseline after 28 days of treatment. Schirmer I, BUT, fluorescein and Rose Bengal did not show any statistical significance in the vehicle group. Topical 0.03% tacrolimus eye drop improved tear stability and ocular surface status in cases of inflammatory or SS-related dry eye. ClinicalTrials.gov Identifier: NCT01850979. Copyright © 2015 British Contact Lens Association. Published by Elsevier Ltd. All rights reserved.

  1. Design of a population-based study of visual impairment in India : The Andhra Pradesh eye disease study

    Directory of Open Access Journals (Sweden)

    Dandona Rakhi

    1997-01-01

    Full Text Available Reliable population-based epidemiologic data regarding vision and ocular morbidity, as well as those about the perceptions of people regarding visual impairment and eye care, are lacking for the most part in the developing world including India. These data are the basis on which effective eye care services can be developed. To meet this need we designed the Andhra Pradesh Eye Disease Study, a population-based epidemiology study of 10,000 people in the Indian state of Andhra Pradesh. The design of this study is described in this paper. Various options for the sample size, study areas, sampling procedure, and recruitment of subjects were considered. A sample size of 10,000 people, 5,000 each in the < or = 30 and > 30 years age groups, was determined to obtain reasonable confidence in estimating the prevalence of diseases and odds ratios for risk factors of interest. A multistage sampling strategy was chosen for the study which was assumed to give a design effect of 1.5 for the estimates. One urban area, Hyderabad, and three rural areas, West Godavari, Adilabad and Mahbubnagar districts, were selected in Andhra Pradesh. Interview instruments were developed to obtain detailed information about demographic data, diet, ocular and systemic history, risk factors for eye diseases, visual function, quality of life, barriers to eye care, and knowledge about eye diseases. A detailed examination procedure was devised to obtain a broad range of normative and abnormal data related to eyes and vision. A protocol was developed for doing automated visual fields, slitlamp and fundus photography. Computer databases were made in FoxPro for data entry and subsequent analysis with SPSS. Pilot studies were done to test the instruments, procedures, and logistics of the study in urban and rural areas. Information from the Andhra Pradesh Eye Disease Study is expected to help in planning and implementation of effective long-term preventive, curative, and

  2. One-Eyed Reading May Help Dyslexic Children—Study

    Institute of Scientific and Technical Information of China (English)

    孙颖

    2000-01-01

    本文的一个重要名词是Dyslexic(adj.),查英汉词典,得到的释义是:诵读困难的。什么是“诵读困难的”?令查阅人似懂非懂。因为,“诵读困难的”的解释可能是心理的(如注意力分散等),也可能是生理的(如近视等)。查阅英英词典,问题便迎刃而解。 Dyslexia(n.):inability to read,considered by modern educational thinkersas a condition to be treated and cured like an illness.(见Longman Dictionaryof Contemporary English,p.344)—此释义告诉读者,所谓Dyslexic,实指眼疾。 此眼疾的患者人数之众令人吃惊: Developmental dyslexia strikes nearly 20 percent of boys and five percent ofgirls,making it difficult for them to learn to read. 这么高的比例是否特指英国?文章未加说明。本文提供了一个简单而神奇的治疗方法:patching one eye(蒙住一只眼睛,而仅仅使用独眼来作阅读)。

  3. Microvasculature of the avian eye: studies on the eye of the duckling with microcorrosion casting, scanning electron microscopy, and stereology.

    Science.gov (United States)

    Hossler, F E; Olson, K R

    1984-06-01

    The microvasculature of the eye of the duckling was studied with microcorrosion casting, scanning electron microscopy, and stereology. Most blood to the eyeball first passes through the arterial ophthalmic rete mirabile, a complex of small arteries which intermixes with a similar complex of veins (venous ophthalmic rete mirabile) at the ventrotemporal angle of the eye. The present study reveals the ultrastructural anatomy and the compact, three-dimensional arrangement of vessels in this rete, which had been shown by previous investigators to function as a countercurrent heat exchanger. Vessels from this rete include the supraorbital and infraorbital arteries, which supply the eyeball anteriorly, and the ophthalmotemporal artery, which supplies the eyeball posteriorly. The internal ophthalmic and ethmoidal arteries, branches of the cerebral carotid artery, anastomose with the ophthalmotemporal artery posteriorly. Blood is distributed to the eyeball anteriorly by two ring arteries: the iridial ring artery, which circumscribes the iris and which receives blood from the long ciliary and infraorbital arteries; and the more peripheral, ciliary ring artery, which receives blood mostly from the infraorbital and ethmoidal arteries. Within the iris is a dense, freely anastomosing bed of capillaries which extends to the edge of the pupil and then loops back beneath the ciliary body. The vasculature of the ciliary body consists of radially arranged plates of anastomosing capillaries of irregular bore which mimic the contours of that organ, but permit changes in pupil diameter. The present study demonstrates the three-dimensional anatomy of the very dense capillary net of the choriocapillaris deep to the retina and the capillary mass of the pecten, and thus supports the finding of earlier investigators that nutrients diffusing from these structures nourish the avascular retina. The pecten consists of a pleated sheet of freely anastomosing capillaries which protrudes into the

  4. A pilot study of eye-tracking devices in intensive care.

    Science.gov (United States)

    Garry, Jonah; Casey, Kelly; Cole, Therese Kling; Regensburg, Angela; McElroy, Colleen; Schneider, Eric; Efron, David; Chi, Albert

    2016-03-01

    Eye-tracking devices have been suggested as a means of improving communication and psychosocial status among patients in the intensive care unit (ICU). This study was undertaken to explore the psychosocial impact and communication effects of eye-tracking devices in the ICU. A convenience sample of patients in the medical ICU, surgical ICU, and neurosciences critical care unit were enrolled prospectively. Patients participated in 5 guided sessions of 45 minutes each with the eye-tracking computer. After completion of the sessions, the Psychosocial Impact of Assistive Devices Scale (PIADS) was used to evaluate the device from the patient's perspective. All patients who participated in the study were able to communicate basic needs to nursing staff and family. Delirium as assessed by the Confusion Assessment Method for the Intensive Care Unit was present in 4 patients at recruitment and none after training. The device's overall psychosocial impact ranged from neutral (-0.29) to strongly positive (2.76). Compared with the absence of intervention (0 = no change), patients exposed to eye-tracking computers demonstrated a positive mean overall impact score (PIADS = 1.30; P = .004). This finding was present in mean scores for each PIADS domain: competence = 1.26, adaptability = 1.60, and self-esteem = 1.02 (all P eye-tracking devices. These 3 outcomes are intertwined with ICU patient outcomes and indirectly suggest that eye-tracking devices might improve outcomes. A more in-depth exploration of the population to be targeted, the device's limitations, and the benefits of eye-tracking devices in the ICU is warranted. Copyright © 2016 Elsevier Inc. All rights reserved.

  5. Assessing for Unilateral Spatial Neglect Using Eye-Tracking Glasses: A Feasibility Study.

    Science.gov (United States)

    Kortman, Brenton; Nicholls, Kate

    2016-08-05

    The aim of this feasibility study was to identify whether eye-tracking glasses could sensitively differentiate unilateral spatial neglect (USN) among a sample of participants who had a stroke, and to determine whether a larger study was viable. A sample of 13 inpatients (N = 7 with neglect, N = 6 without neglect) aged 50-78 years undertook a task while wearing Tobii eye-tracking glasses. The kitchen environment and the task of making a cup of coffee were standardized. Two commonly reported tests for USN, the Bells Test and the Line Crossing Test, were also used as a reference standard for the eye-tracking data. Participants with USN spent significantly more time searching on the right-hand side (p = .006) for items during the task than those without neglect. There was a moderate correlation between eye-tracking data and the Bells Test (r = .622, p = .04). Overall, this study supported the feasibility of using a real-life task with eye-tracking to detect neglect.

  6. High altitude and the eye: a case controlled study in clinical ocular anthropometry of changes in the eye.

    Science.gov (United States)

    Bali, Jatinder; Chaudhary, K P; Thakur, Renu

    2005-01-01

    Tribal natives of two spatially separate districts of Lahaul-Spiti (mean altitude = 3300 m) and Kinnaur (mean altitude = 1,700 m) in the Himalayan state of Himachal Pradesh have lived for centuries as closed isolated groups, marrying within the local community up to the recent past. Studies on highland natives in the Andes have shown differences in chest diameters, lung volumes, hematocrit, and the like, in those living at high altitudes. We wanted to study whether stay at high altitude for generations confers any change in the ocular anthropometry. No study of this nature is available in the literature. We studied the ocular parameters using Snellen's charts, Standard Royal-Air-Force Rule, A-2,500 Sonomed A-Scan, Goldmann's aplanation tonometer, and S-7,000 Autorefractometer on 50 healthy volunteers at the Indira Gandhi Medical College Out Patient Department at Shimla (mean altitude = 2,100 m). Those living at higher altitudes in Lahaul-Spiti [LS] (n = 10) had significantly wider nose bridge width (p < 0.05); inter-inner canthal distance [IICD] (p < 0.05); inter-outer canthal distance [IOCD] (p < 0.05); and interpupillary distance [IPD] (p < 0.05) than the group living at Kinnaur (n = 40) at lower elevation. The LS group also had narrower palpebral fissure length in the vertical dimension (p = 0.05) and a lower IOP (p = 0.002) than the Kinnaur group. The axial length, lens thickness, and anterior chamber depth were comparable in the two groups. It appears that the eye and its adnexa respond to hypoxia, ultraviolet radiations, and persistent snow cover at high altitude by altering its anthropometry in a subtle but discernible manner. This was a hitherto unexplored area in the literature. Further studies to elucidate and substantiate the findings of the study are indicated.

  7. Processing emotion from the eyes: a divided visual field and ERP study.

    Science.gov (United States)

    Beaton, Alan A; Fouquet, Nathalie C; Maycock, Nicola C; Platt, Eleanor; Payne, Laura S; Derrett, Abigail

    2012-01-01

    The right cerebral hemisphere is preferentially involved in recognising at least some facial expressions of emotion. We investigated whether there is a laterality effect in judging emotions from the eyes. In one task a pair of emotionally expressive eyes presented in central vision had to be physically matched to a subsequently presented set of eyes in one or other visual hemifield (eyes condition). In the second task a word was presented centrally followed by a set of eyes to left or right hemifield and the participant had to decide whether the word correctly described the emotion portrayed by the laterally presented set of eyes (word condition). Participants were a group of undergraduate students and a group of older volunteers (> 50). There was no visual hemifield difference in accuracy or raw response times in either task for either group, but log-transformed times showed an overall left hemifield advantage. Contrary to the right hemisphere ageing hypothesis, older participants showed no evidence of a relative right hemisphere decline in performance on the tasks. In the younger group mean peak amplitude of the N170 component of the EEG at lateral posterior electrode sites was significantly greater over the right hemisphere (T6/PO2) than the left (T5/PO1) in both the perceptual recognition task and the emotional judgement task. It was significantly greater for the task of judging emotion than in the eyes-matching task. In future it would be useful to combine electrophysiological techniques with lateralised visual input in studying lateralisation of emotion with older as well as younger participants.

  8. Dust And Gas Morphology Of Comets 81P/Wild 2, 10P/Tempel 2, And 103P/Hartley 2

    Science.gov (United States)

    Knight, Matthew M.; Schleicher, D. G.

    2010-10-01

    As part of the ongoing program to study comets at Lowell Observatory, we present our recent observations of Jupiter Family Comets 81P/Wild 2, 10P/Tempel 2, and 103P/Hartley 2. All comets were observed with the Hall 1.1-m telescope at Lowell Observatory using broadband and narrowband optical filters to isolate gas and dust coma morphology. These filters allow us to compare the spatial distribution of various gas species and to infer properties of the nucleus such as the pole orientation, rotation period, and the number and location of active regions. Wild 2 reached perihelion in February 2010, its first return since the Stardust encounter in 2004. We observed it on 22 nights between October 2009 and June 2010. Image enhancement reveals two dust jets whose seasonal activities are consistent with those described by Farnham and Schleicher (2005; Icarus 173, 553-558). Additionally, we observed a CN jet that appears to be coincident with one of the dust jets. Tempel 2 has a favorable observing scenario in 2010, with viewing geometry significantly different than in the previous favorable apparitions of 1988 and 1999, which should further constrain the pole solution. We began observing Tempel 2 in March 2010, and observations will continue into 2011, with the comet near opposition throughout the fall. Preliminary analysis reveals a single CN jet that does not vary with rotational phase and a dust jet that is offset from the CN jet. These features are consistent with post-perihelion observations in 1999 that will be presented separately by Schwieterman et al. Hartley 2 passes within 0.12 AU of Earth in October 2010 and is the target of the EPOXI spacecraft flyby in November 2010. Imaging commenced in July 2010 and we will present ongoing results at the meeting. This work was supported by the NASA Planetary Astronomy program.

  9. Histological study of middle layer of rabbit fish eye (siganus javus)

    Institute of Scientific and Technical Information of China (English)

    Amir Sattari; Marziyeh Asli; Foroogh sadat Mansoori; Reza Kheirandish; Hossein Yavari

    2012-01-01

    Objectives: This study investigates the histology of the middle layer of the eye in rabbit fish Siganus javus. Methods: The eyes of twelve healthy fish were enucleated and histologic sections of 6µ were prepared. The sections were stained with Hematoxyline & Eosine (H&E) and Masson trichrom then were observed using light microscopy. Results: The middle or vascular layer consisted of the choroid and iris. The result revealed that the choroid coat was subdivided into five laminae: 1. Suprachoroid layer 2. Substina propria included choroidal gland or retemirabile, melanoid layers and connective tissue 3. Fibrouse layer 4. Choriocapillary layer 5. Separator layer. The extension of the choroid coat into the anterior compartment made the iris which mainly composed of connective tissue, blood vessels, melanocyte and a smooth muscle at the posterior part of the iris, adjacent to the pupil. The choroid coat did not continue rostrally adjacent to the cornea. Suspensory apparatus of the lens of the Siganus javus eye consisted of a dorsal suspensory ligament and a ventral retractor muscle. Conclusions: The diversity and deviation in the detail of microscopic structures in the eye of teleosts is approved through this microscopic study in middle layer of rabbit fish eye however the five differentiated parts of choroid were distinguished as in many telelost species.

  10. Fast Algorithm for Computing the Discrete Hartley Transform of Type-II

    Directory of Open Access Journals (Sweden)

    Mounir Taha Hamood

    2016-06-01

    Full Text Available The generalized discrete Hartley transforms (GDHTs have proved to be an efficient alternative to the generalized discrete Fourier transforms (GDFTs for real-valued data applications. In this paper, the development of direct computation of radix-2 decimation-in-time (DIT algorithm for the fast calculation of the GDHT of type-II (DHT-II is presented. The mathematical analysis and the implementation of the developed algorithm are derived, showing that this algorithm possesses a regular structure and can be implemented in-place for efficient memory utilization.The performance of the proposed algorithm is analyzed and the computational complexity is calculated for different transform lengths. A comparison between this algorithm and existing DHT-II algorithms shows that it can be considered as a good compromise between the structural and computational complexities.

  11. A simplification of the fractional Hartley transform applied to image security system in phase

    Science.gov (United States)

    Jimenez, Carlos J.; Vilardy, Juan M.; Perez, Ronal

    2017-01-01

    In this work we develop a new encryption system for encoded image in phase using the fractional Hartley transform (FrHT), truncation operations and random phase masks (RPMs). We introduce a simplification of the FrHT with the purpose of computing this transform in an efficient and fast way. The security of the encryption system is increased by using nonlinear operations, such as the phase encoding and the truncation operations. The image to encrypt (original image) is encoded in phase and the truncation operations applied in the encryption-decryption system are the amplitude and phase truncations. The encrypted image is protected by six keys, which are the two fractional orders of the FrHTs, the two RPMs and the two pseudorandom code images generated by the amplitude and phase truncation operations. All these keys have to be correct for a proper recovery of the original image in the decryption system. We present digital results that confirm our approach.

  12. MUESTREO DE RESPUESTA ALEATORIZADAS CON PROBABILIDADES DESIGUALES: EL ESTIMADOR DE RAO-HARTLEY-COCHRAN

    Directory of Open Access Journals (Sweden)

    Víctor H. Soberanis Cruz1-, Jaime D. Cuevas Domínguez

    2010-09-01

    Full Text Available The technique of Randomized Response has been introduced to reduce the risk of evasive answer or no-response in survey samplings of sensitive issues to estimate the total of individuals with that sensitive characteristic. We also know that highly efficient strategies of estimation require strong auxiliary information. Hence, in this article we obtain and compare two estimators: The Rao-Hartley-Cochran (RHC estimator with Warner´s model and the RHC estimator with Greenberg´s model, both in a finite population setting.We will show via simulation that , the RHC -estimator in Warner´s model is less efficient than , the RHC -estimator in Greenberg’s modelK

  13. Histological study of the annular ligament in the rabbitfish eye (Siganus sp.

    Directory of Open Access Journals (Sweden)

    Marziye Asli

    2012-12-01

    Full Text Available Rabbitfish is economically valuable teleost species which lives in shallow coastalwaters. Two species of rabbit fish have been recognized in southern sea of Iran (Persiangulf as namely Siganus sutor and Siganus javus. In the current study, in order toinvestigate the histology of the annular ligament of the S. javus’ eye, the prepared sectionsof the eyes of twelve healthy specimens were studied under light microscope. The resultsrevealed that annular ligament is a crescent shape structure which is situated between thescleral stroma anteriorly and the iris posteriorly. It contains a vascularized, amorphousand granular matrix with fibers of dense connective tissue; high glycogen content andmelanin pigments.

  14. Histological study of the annular ligament in the rabbitfish eye (Siganus sp.).

    Science.gov (United States)

    Asli, Marziye; Mansoori, Forooghsadat; Sattari, Amir

    2012-01-01

    Rabbitfish is economically valuable teleost species which lives in shallow coastal waters. Two species of rabbit fish have been recognized in southern sea of Iran (Persian gulf) as namely Siganus sutor and Siganus javus. In the current study, in order to investigate the histology of the annular ligament of the S. javus' eye, the prepared sections of the eyes of twelve healthy specimens were studied under light microscope. The results revealed that annular ligament is a crescent shape structure which is situated between the scleral stroma anteriorly and the iris posteriorly. It contains a vascularized, amorphous and granular matrix with fibers of dense connective tissue; high glycogen content and melanin pigments.

  15. Ultraviolet OH prompt emission in the innermost coma of 103P/Hartley 2

    Science.gov (United States)

    La Forgia, F.; A'Hearn, M.; Lazzarin, M.; Magrin, S.; Bertini, I.; Pajola, M.; Barbieri, C.; Kueppers, M.

    2014-07-01

    The hyperactive Jupiter-family comet 103P/Hartley 2, the target of the EPOXI mission, has been visited on 4 November 2010 at a distance of 694 km, when it was at 1.064 au from the Sun. Spectral observations of the ambient coma show that H_2O is enhanced from the central waist, while CO_2 and icy grains seem to be coming out mainly from the two lobes [1,2]. Visible observations in the OH filter of the MRI camera onboard EPOXI have been used to investigate the distribution of the OH daughter species in the coma. These data reveal an evident radial structure in the very inner coma below 35 km from the nucleus (see Figure), appearing to be coming directly from the nucleus, in the region of the central waist. This is in agreement with the water distribution found by [1]. The OH resonance fluorescence emission band at 308.5 nm, caused by the transition A^2Σ-X^2Π (0,0), has been used indeed for years as a tracer of water parent molecules. Nevertheless, even for the active Sun, the OH fluorescence lifetime is about 10^{5} s, suggesting that it is not expected to be observed so close to the nucleus. OH has been found to cause prompt emission (PE) at both IR and UV wavelengths and has been tentatively detected in a few comets [3-6]. We report theoretical computations showing a strong possibility that the innermost OH structure observed in the MRI images of Hartley 2 could possibly be associated with OH ultraviolet PE.

  16. Measurements of Corneal Thickness in Eyes with Pseudoexfoliation Syndrome: Comparative Study of Different Image Processing Protocols

    Directory of Open Access Journals (Sweden)

    Katarzyna Krysik

    2017-01-01

    Full Text Available Purpose. Comparative analysis of central and peripheral corneal thickness in PEX patients using three different imaging systems: Pentacam-Scheimpflug device, time-domain optical coherence tomography (OCT Visante, and swept-source OCT Casia. Materials and Methods. 128 eyes of 80 patients with diagnosed PEX were examined and compared with 112 normal, non-PEX eyes of 72 cataract patients. The study parameters included 5 measured zones: central and 4 peripheral (superior, inferior, nasal, and temporal. Results. The mean CCT in eyes with PEX syndrome measured with all three instruments was thicker than that in normal eyes. Corneal thickness measurements in the PEX group were statistically significantly different between Pentacam and OCT Casia: central corneal thickness (p=0.04, inferior corneal zone (p=0.01, and nasal and temporal corneal zones (p<0.01. Between Pentacam and OCT Visante inferior, nasal and temporal corneal zones were statistically significantly different (p<0.01. Between OCT Casia and OCT Visante, there were no statistically significant differences in measured parameters values. Conclusion. The central corneal thickness in eyes with PEX syndrome measured with three different independent methods is higher than that in the non-PEX group, and despite variable peripheral corneal thickness, this one parameter is still crucial in intraocular pressure measurements.

  17. Configural processing in body posture recognition: an eye-tracking study.

    Science.gov (United States)

    Tao, Weidong; Sun, Hongjin

    2013-11-13

    The body inversion effect is the finding that inverted body posture pictures are more difficult to recognize than upright body posture pictures are. The present study reinvestigated the body inversion effect in human observers using behavioral and eye movement measures to explore whether the body inversion effect correlates with specific eye movement features. Results showed that body postures elicited a robust and stable body inversion effect in reaction time throughout the experimental sessions. Eye-tracking data showed that the body inversion effect was robust only in the first fixation duration, but not in the second fixation duration. The analysis of the regions of interest showed that most fixations were located in the upper body for both the upright and the inverted body postures. Compared with inverted body postures, the upright postures led to a shorter reaction time and a shorter first fixation duration, but a larger portion of time to fixate on the head region, suggesting that participants tended to use head as a reference point to process upright body postures. For both the behavioral and the eye movement measures, the body inversion effect was robust for biomechanically possible body postures. However, for biomechanically impossible body postures (with angular manipulation of two joints), the effect was mixed. Although the error rate failed to show the body inversion effect, the reaction time measure and most eye movement measures, however, showed a body inversion effect. Overall, these results suggested that upright body postures are processed in expertise recognition and are processed configurally by human observers.

  18. Unique Contributions of Eye-Tracking Research to the Study of Learning with Graphics

    Science.gov (United States)

    Mayer, Richard E.

    2010-01-01

    The author examines the empirical, methodological, theoretical, and practical contributions of the six studies in this special issue on eye tracking as a tool to study and enhance multimedia learning. The design of learning environments involving graphics should be consistent with a research-based theory of how people learn and evidence-based…

  19. Unique Contributions of Eye-Tracking Research to the Study of Learning with Graphics

    Science.gov (United States)

    Mayer, Richard E.

    2010-01-01

    The author examines the empirical, methodological, theoretical, and practical contributions of the six studies in this special issue on eye tracking as a tool to study and enhance multimedia learning. The design of learning environments involving graphics should be consistent with a research-based theory of how people learn and evidence-based…

  20. "Planning eye health services in Varamin district, Iran: a cross-sectional study".

    Science.gov (United States)

    Katibeh, Marzieh; Blanchet, Karl; Akbarian, Shadi; Hosseini, Sara; Ahmadieh, Hamid; Burton, Matthew J

    2015-04-03

    A recent survey of avoidable blindness in Varamin District, Iran, identified moderately high levels of visual impairment (10%) and blindness (1.5%) in people >50 years. This study aimed to define current provision, identify gaps and suggest practical solutions for improving eye health services in this area. The World Health Organization (WHO) framework for analyzing health systems has several key components: service delivery, health workforce, information system, medical products and technologies, financing, and governance. We used this structure to investigate the strengths and weaknesses of the eye health system in Varamin. All public and private eye care facilities and a random selection of primary health care (PHC) units were assessed using semi-structured researcher-administered questionnaires. Varamin has 16 ophthalmic clinics, including two secondary hospitals that provide cataract surgery. There were ten ophthalmologists (1:68,000 population), two ophthalmic nurses and five optometrists working in Varamin district. There were no eye care social or community workers, ophthalmic counsellors, low vision rehabilitation staff. Although the Vision 2020 target for ophthalmologists has been met, numbers of other eye care staff were insufficient. The majority of patients travel to Tehran for surgery. The recent survey identified cataract as the leading cause of blindness, despite the availability of surgical services in the district and high health insurance coverage. Poor awareness is a major barrier. No units had a written blindness prevention plan, formal referral pathways or sufficient eye health promotion activities. Only one of the PHC units referred people with diabetes for retinal examination. There is partial integration between eye care services and the general health system particularly for prevention of childhood blindness: chemo-prophylaxis for ophthalmia neonatorum, school vision tests, measles immunization and Vitamin A supplementation. This analysis

  1. Genetic mechanisms involved in the evolution of the cephalopod camera eye revealed by transcriptomic and developmental studies

    Directory of Open Access Journals (Sweden)

    Ogura Atsushi

    2011-06-01

    hybridization analysis of embryonic pygmy squid. Conclusion We identified 156 genes positively selected in the cephalopod lineage and 1,571 genes commonly found in the cephalopod and vertebrate camera eyes from the analysis of cephalopod camera eye specificity at the expression level. Experimental validation showed that the cephalopod camera eye-specific candidate genes include those expressed in the outer part of the optic lobes, which unique to coleoid cephalopods. The results of this study suggest that changes in gene expression and in the primary structure of proteins (through positive selection from those in the common molluscan ancestor could have contributed, at least in part, to cephalopod camera eye acquisition.

  2. Prognostic indicators for no light perception after open-globe injury: eye injury vitrectomy study.

    Science.gov (United States)

    Feng, Kang; Hu, Yun Tao; Ma, Zhizhong

    2011-10-01

    To describe ocular characteristics, surgical interventions, and anatomic and visual outcomes of traumatized eyes with no light perception (NLP) following open-globe injury and to investigate prognostic predictors for NLP cases after open-globe injury. Interventional case series study. Thirty-three traumatized eyes with NLP were selected from the Eye Injury Vitrectomy Study database, a hospital-based multicenter prospective cohort study. Inclusion criteria were NLP cases following open-globe injury with outcomes of anatomic restoration, phthisis bulbi, or enucleation. Exclusion criteria were cases with missing records, undergoing vitrectomy after injury at nonparticipating hospitals, direct optic head injury, endophthalmitis, and hypotonous or silicone oil-sustained eyes. All cases underwent vitreoretinal surgery or enucleation after exploratory surgery and were followed up for at least 6 months. Two outcomes were assessed: favorable outcome (anatomically restored eye globes with light perception [LP] or better vision) and unfavorable outcome (NLP, phthisis bulbi, or enucleation). The following 7 risk factors were significant between the 2 groups: rupture (P = .021); open globe III (P = .046); scleral wound ≥10 mm (P = .001); ciliary body damage (P < .001); severe intraocular hemorrhage (P = .005); closed funnel retinal detachment or retinal prolapse (P = .005); and choroidal damage (P = .001). These 7 risk factors are possible predictors of poor prognosis. Traumatized eyes with NLP can be anatomically restored with LP or better vision if vitreoretinal surgery is attempted, and a favorable anatomic and visual outcome is increased by having a decreased number of these risk factors. Copyright © 2011 Elsevier Inc. All rights reserved.

  3. Radiation protection to the eye and thyroid during diagnostic cerebral angiography: a phantom study.

    Science.gov (United States)

    Shortt, C P; Malone, L; Thornton, J; Brennan, P; Lee, M J

    2008-08-01

    We measured radiation doses to the eye and thyroid during diagnostic cerebral angiography to assess the effectiveness of bismuth and lead shields at dose reduction. Phantom head angiographic studies were performed with bismuth (study 1) and lead shields (study 2). In study 1 (12 phantoms), thermoluminescent dosimeters (TLD) were placed over the eyes and thyroid in three groups: (i) no shields (four phantoms); (ii) anterior bismuth shields (four phantoms) and (iii) anterior and posterior bismuth shields (four phantoms). In a second study (eight phantoms), lead shields were placed over the thyroid only and TLD dose measurements obtained in two groups: (i) no shielding (four phantoms) and (ii) thyroid lead shielding (four phantoms). A standard 4-vessel cerebral angiogram was performed on each phantom. Study 1 (bismuth shields) showed higher doses to the eyes compared with thyroid (mean 13.03 vs 5.98 mSv, P shielding did not significantly reduce dose to either eyes or thyroid in the measured TLD positions. In study 2, a significant thyroid dose reduction was found with the use of lead shields (47%, mean 2.46 vs 4.62 mSv, P shielding is impractical and interferes with diagnostic capability. Thyroid lead shielding yields significant protection to the thyroid, is not in the field of view and should be used routinely.

  4. Love is in the gaze: an eye-tracking study of love and sexual desire.

    Science.gov (United States)

    Bolmont, Mylene; Cacioppo, John T; Cacioppo, Stephanie

    2014-09-01

    Reading other people's eyes is a valuable skill during interpersonal interaction. Although a number of studies have investigated visual patterns in relation to the perceiver's interest, intentions, and goals, little is known about eye gaze when it comes to differentiating intentions to love from intentions to lust (sexual desire). To address this question, we conducted two experiments: one testing whether the visual pattern related to the perception of love differs from that related to lust and one testing whether the visual pattern related to the expression of love differs from that related to lust. Our results show that a person's eye gaze shifts as a function of his or her goal (love vs. lust) when looking at a visual stimulus. Such identification of distinct visual patterns for love and lust could have theoretical and clinical importance in couples therapy when these two phenomena are difficult to disentangle from one another on the basis of patients' self-reports.

  5. Healthy Eyes

    Science.gov (United States)

    ... los Ojos Cómo hablarle a su oculista Healthy Eyes Having a comprehensive dilated eye exam is one ... or contact lenses. What is a comprehensive dilated eye exam? A comprehensive dilated eye exam is a ...

  6. Basic study of the portable fatigue meter: effects of illumination, distance from eyes and age.

    Science.gov (United States)

    Hosokawa, T; Mikami, K; Saito, K

    1997-09-01

    Several aspects of a new, small and inexpensive fatigue assessment tool, the Portable Fatigue Meter (PFM), were studied. In the first experiment the effects of room illumination and distance between the PFM and the eyes on critical flicker fusion frequency (CFF) values were examined. The results revealed that the PFM CFF value varied significantly as a function of the distance between the indicator and the eyes, but it was not affected by room illumination. The effect of ageing on the PFM CFF value was assessed in a second experiment. The results suggested that PFM CFF values are significantly smaller in middle-aged females than in younger females.

  7. APPLICATION OF EYE TRACKING FOR MEASUREMENT AND EVALUATION IN HUMAN FACTORS STUDIES IN CONTROL ROOM MODERNIZATION

    Energy Technology Data Exchange (ETDEWEB)

    Kovesdi, C.; Spielman, Z.; LeBlanc, K.; Rice, B.

    2017-05-01

    An important element of human factors engineering (HFE) pertains to measurement and evaluation (M&E). The role of HFE-M&E should be integrated throughout the entire control room modernization (CRM) process and be used for human-system performance evaluation and diagnostic purposes with resolving potential human engineering deficiencies (HEDs) and other human machine interface (HMI) design issues. NUREG-0711 describes how HFE in CRM should employ a hierarchical set of measures, particularly during integrated system validation (ISV), including plant performance, personnel task performance, situation awareness, cognitive workload, and anthropometric/ physiological factors. Historically, subjective measures have been primarily used since they are easier to collect and do not require specialized equipment. However, there are pitfalls with relying solely on subjective measures in M&E such that negatively impact reliability, sensitivity, and objectivity. As part of comprehensively capturing a diverse set of measures that strengthen findings and inferences made of the benefits from emerging technologies like advanced displays, this paper discusses the value of using eye tracking as an objective method that can be used in M&E. A brief description of eye tracking technology and relevant eye tracking measures is provided. Additionally, technical considerations and the unique challenges with using eye tracking in full-scaled simulations are addressed. Finally, this paper shares preliminary findings regarding the use of a wearable eye tracking system in a full-scale simulator study. These findings should help guide future full-scale simulator studies using eye tracking as a methodology to evaluate human-system performance.

  8. Case-control study of risk factors for no light perception after open-globe injury: eye injury vitrectomy study.

    Science.gov (United States)

    Feng, Kang; Shen, Lijun; Pang, Xiuqin; Jiang, Yanrong; Nie, Hongping; Wang, Zhijun; Hu, Yuntao; Ma, Zhizhong

    2011-11-01

    Investigate possible risk factors of no light perception (NLP) after open-globe injury. Explore whether these risk factors are predictors for an unfavorable visual outcome. This case-control study matched 72 eyes with NLP according to type and zone of injury to 2 controls per case with light perception or better vision. Cases were selected from the Eye Injury Vitrectomy Study database. All injured eyes in the study underwent surgical intervention. Ciliary body damage (odds ratio = 2.94), closed funnel retinal detachment (odds ratio = 2.43), and choroidal damage (odds ratio = 2.80) were independent risk factors for NLP after open-globe injury. There were 67 traumatized eyes with NLP that had ≥1 of these risk factors. In 43 of the cases (64.2%), the eyes recovered light perception or better after vitreoretinal surgery. The five traumatized NLP cases without these risk factors obtained a favorable visual outcome after vitreoretinal surgery. There was no statistical significance in visual outcome between them (P = 0.162). Ciliary body damage, closed funnel retinal detachment, and choroidal damage are independent risk factors for NLP posttrauma but not prognostic indicators for NLP visual outcome. Traumatized eyes with NLP may recover light perception or better vision if appropriate interventional measures are used for treatment of the injured ciliary body, retina, and choroid.

  9. Dry Eye Disease Incidence Associated with Chronic Graft-Host Disease: Nonconcurrent Cohort Study (An American Ophthalmological Society Thesis).

    Science.gov (United States)

    Mian, Shahzad I; De la Parra-Colín, Paola; De Melo-Franco, Rafael; Johnson, Christopher; Barrientos-Gutierrez, Tonatiuh

    2015-09-01

    To determine if chronic graft-versus-host disease (cGVHD) after allogeneic hematopoietic stem cell transplantation (HSCT) is associated with stable or progressive dry eye disease and to determine the true incidence in patients with no prior history of dry eye disease. A nonconcurrent cohort study at a single institution with 136 patients who had no previous history of dry eye disease before HSCT. Survival analysis was used to estimate dry eye disease incidence. The incidence rate was calculated using life tables as the number of observed dry eye disease cases divided by the person-time at risk accumulated by the cohort. Transition probabilities were calculated from time of transplant to time of diagnosis, and then to last recorded visit. Incidence rate was 0.8 cases of dry eye disease per person-year, and half of the population at risk developed dry eye disease during the first 10 months post transplant. Time to develop dry eye disease was 2.5 months for mild dry eye disease, 9.6 months for moderate dry eye disease, and 13.2 months for severe dry eye disease. In terms of cumulative incidence, 73% of subjects developed dry eye disease (50% mild, 16% moderate, and 7% severe) at the time of diagnosis. Our findings suggest that dry eye disease associated with cGVHD is an extremely frequent event and shows a wide spectrum of severity, with a mild form presenting early and a moderate to severe form presenting later after HSCT. These findings need to be studied further to elucidate if these are two different pathophysiological entities or just different expressions of the same pathology.

  10. Dry Eye Disease Incidence Associated with Chronic Graft-Host Disease: Nonconcurrent Cohort Study (An American Ophthalmological Society Thesis)

    Science.gov (United States)

    Mian, Shahzad I.; De la Parra-Colín, Paola; De Melo-Franco, Rafael; Johnson, Christopher; Barrientos-Gutierrez, Tonatiuh

    2015-01-01

    Purpose: To determine if chronic graft-versus-host disease (cGVHD) after allogeneic hematopoietic stem cell transplantation (HSCT) is associated with stable or progressive dry eye disease and to determine the true incidence in patients with no prior history of dry eye disease. Methods: A nonconcurrent cohort study at a single institution with 136 patients who had no previous history of dry eye disease before HSCT. Survival analysis was used to estimate dry eye disease incidence. The incidence rate was calculated using life tables as the number of observed dry eye disease cases divided by the person-time at risk accumulated by the cohort. Transition probabilities were calculated from time of transplant to time of diagnosis, and then to last recorded visit. Results: Incidence rate was 0.8 cases of dry eye disease per person-year, and half of the population at risk developed dry eye disease during the first 10 months post transplant. Time to develop dry eye disease was 2.5 months for mild dry eye disease, 9.6 months for moderate dry eye disease, and 13.2 months for severe dry eye disease. In terms of cumulative incidence, 73% of subjects developed dry eye disease (50% mild, 16% moderate, and 7% severe) at the time of diagnosis. Conclusions: Our findings suggest that dry eye disease associated with cGVHD is an extremely frequent event and shows a wide spectrum of severity, with a mild form presenting early and a moderate to severe form presenting later after HSCT. These findings need to be studied further to elucidate if these are two different pathophysiological entities or just different expressions of the same pathology. PMID:27507907

  11. Studies of cytotoxic antibodies against eye muscle antigens in patients with thyroid-associated ophthalmopathy

    Energy Technology Data Exchange (ETDEWEB)

    Zhang, Z.-G.; Hiromatsu, Y.; Salvi, M.; Triller, H.; Bernard, N.; Wall, J.R. (Thyroid Research Unit, The Montreal General Hospital Research Institute, Montreal, Quebec (Canada)); Medeiros-Neto, G.; Iacona, A.; Lima, N. (Thyroid Clinic, Hospital das Clinicas, Sao Paulo (Brazil))

    1989-01-01

    We have studied the prevalence and significance of cytotoxic antibodies against human eye muscle cells, as detected in antibody-dependent cell-mediated cytotoxicity (ADCC) and complement-mediated antibody-dependent cytotoxicity (CMAC) in {sup 51}Cr release assays, in patients with Graves' ophthalmopathy or Hashimoto's thyroiditis. A high prevalence of positive ADCC tests was found in all groups of patients with ophthalmopathy tested. Tests were positive in 64% of patients with Graves' ophthalmopathy from an area of severe iodine deficiency (Sao Paulo) and in 64% of such patients from an iodine replete area (Montreal). In patients with so-called ''euthyroid ophthalmopathy'', i.e. eye disease associated with thyroiditis, ADCC tests were positive in 75 and 38% of patients from the two areas, respectively, while tests were positive in 40 and 22%, respectively, of patients with Graves' hyperthyroidism without evident eye disease. In normal subjects, levels of {sup 51}Cr release was always at background levels. In a group of patients from the high-iodine area, levels of antibodies in ADCC correlated positively with the intraocular pressure (mmHg) in primary position as a parameter of eye muscle dysfunction. In patients with ophthalmopathy, positive ADCC tests were assciated with antibodies to eye muscle membrane antigens of 55,65 and 95 kD as detected by immunoblotting, although the correlation was not close for any antigen. in contrast, CMAC tests were negative in all patients with ophthalmopathy. We also tested 9 mouse and 10 human monoclonal antibodies, reactive with orbital antigens in an enzyme-linked immunosorbent assay, for cytotoxic activity, in ADCC and CMAC, against eye muscle and thyroid cells. All monoclonal antibodies were of the IgM class and negative in ADCC assays. (Abstract Truncated)

  12. What the Age-Related Eye Disease Studies Mean for You (AREDS2)

    Science.gov (United States)

    ... the AREDS Means for You For the Public: What the AREDS Means for You What the Age-Related Eye Disease Studies Mean for ... related nutritional supplements with a health care professional. What is the original AREDS formulation? 500 milligrams (mg) ...

  13. A Metabolome-Wide Study of Dry Eye Disease Reveals Serum Androgens as Biomarkers

    NARCIS (Netherlands)

    Vehof, Jelle; Hysi, Pirro G.; Hammond, Christopher J.

    Purpose: To test the association between serum metabolites and dry eye disease (DED) using a hypothesisfree metabolomics approach. Design: Cross-sectional association study. Participants: A total of 2819 subjects from the population-representative TwinsUK cohort in the United Kingdom, with a mean

  14. Reading in Spanish as a Second Language: An Eye-Tracking Study

    Science.gov (United States)

    Enkin, Elizabeth; Nicol, Janet; Brooks, Zachary; Zavaleta, Kaitlyn Leigh

    2017-01-01

    In the present study, we examine sentence reading in low-proficiency Spanish learners using an eye-tracking methodology. This method reveals the real-time, uninterrupted process of reading comprehension, and can therefore shed light on L2 learners' functional proficiency. We created sentence pairs that were identical except for one word. The…

  15. The Face Perception System becomes Species-Specific at 3 Months: An Eye-Tracking Study

    Science.gov (United States)

    Di Giorgio, Elisa; Meary, David; Pascalis, Olivier; Simion, Francesca

    2013-01-01

    The current study aimed at investigating own- vs. other-species preferences in 3-month-old infants. The infants' eye movements were recorded during a visual preference paradigm to assess whether they show a preference for own-species faces when contrasted with other-species faces. Human and monkey faces, equated for all low-level perceptual…

  16. Seeing what teachers see: Exploring the use of eye tracking in teacher expertise studies

    NARCIS (Netherlands)

    Wolff, Charlotte; Van 'T Zelfde, Hans; Jarodzka, Halszka; Boshuizen, Els

    2012-01-01

    Wolff, C., Van ’T Zelfde, H., Jarodzka, H., & Boshuizen, H. P. A. (2012, August). Seeing what teachers see: Exploring the use of eye tracking in teacher expertise studies. Poster presented at the EARLI SIG Learning and Professional Development, Antwerp, Belgium.

  17. Eye Tracking as a Measure of Noticing: A Study of Explicit Recasts in SCMC

    Science.gov (United States)

    Smith, Bryan

    2012-01-01

    This study investigated whether eye-tracking technology could be employed as a measure of noticing of corrective feedback (in the form of explicit recasts) during NS-NNS task-based synchronous computer-mediated communication (SCMC). Pairs of university-level learners of English (n = 18) engaged in a short chat interaction task with a native…

  18. Infant and Adult Perceptions of Possible and Impossible Body Movements: An Eye-Tracking Study

    Science.gov (United States)

    Morita, Tomoyo; Slaughter, Virginia; Katayama, Nobuko; Kitazaki, Michiteru; Kakigi, Ryusuke; Itakura, Shoji

    2012-01-01

    This study investigated how infants perceive and interpret human body movement. We recorded the eye movements and pupil sizes of 9- and 12-month-old infants and of adults (N = 14 per group) as they observed animation clips of biomechanically possible and impossible arm movements performed by a human and by a humanoid robot. Both 12-month-old…

  19. Expertise differences in air traffic control: An eye-tracking study

    NARCIS (Netherlands)

    Van Meeuwen, Ludo; Jarodzka, Halszka; Brand-Gruwel, Saskia; Kirschner, Paul A.; De Bock, Jeano; Van Merriënboer, Jeroen

    2012-01-01

    Van Meeuwen, L. W., Jarodzka, H., Brand-Gruwel, S., Kirschner, P. A., De Bock, J. J. P. R., & Van Merriënboer, J. J. G. (2012, April). Expertise differences in air traffic control: An eye-tracking study. Paper presented at the American Educational Research Association Annual Meeting 2012, Vancouver,

  20. Incidental L2 Vocabulary Acquisition "from" and "while" Reading: An Eye-Tracking Study

    Science.gov (United States)

    Pellicer-Sánchez, Ana

    2016-01-01

    Previous studies have shown that reading is an important source of incidental second language (L2) vocabulary acquisition. However, we still do not have a clear picture of what happens when readers encounter unknown words. Combining offline (vocabulary tests) and online (eye-tracking) measures, the incidental acquisition of vocabulary knowledge…

  1. Seeing what teachers see: Exploring the use of eye tracking in teacher expertise studies

    NARCIS (Netherlands)

    Wolff, Charlotte; Van 'T Zelfde, Hans; Jarodzka, Halszka; Boshuizen, Els

    2012-01-01

    Wolff, C., Van ’T Zelfde, H., Jarodzka, H., & Boshuizen, H. P. A. (2012, August). Seeing what teachers see: Exploring the use of eye tracking in teacher expertise studies. Poster presented at the EARLI SIG Learning and Professional Development, Antwerp, Belgium.

  2. Expertise differences in air traffic control: An eye-tracking study

    NARCIS (Netherlands)

    Van Meeuwen, Ludo; Jarodzka, Halszka; Brand-Gruwel, Saskia; Kirschner, Paul A.; De Bock, Jeano; Van Merriënboer, Jeroen

    2012-01-01

    Van Meeuwen, L. W., Jarodzka, H., Brand-Gruwel, S., Kirschner, P. A., De Bock, J. J. P. R., & Van Merriënboer, J. J. G. (2012, April). Expertise differences in air traffic control: An eye-tracking study. Paper presented at the American Educational Research Association Annual Meeting 2012, Vancouver,

  3. Eye Tracking as a Measure of Noticing: A Study of Explicit Recasts in SCMC

    Science.gov (United States)

    Smith, Bryan

    2012-01-01

    This study investigated whether eye-tracking technology could be employed as a measure of noticing of corrective feedback (in the form of explicit recasts) during NS-NNS task-based synchronous computer-mediated communication (SCMC). Pairs of university-level learners of English (n = 18) engaged in a short chat interaction task with a native…

  4. Age- and fatigue-related markers of human faces: an eye-tracking study.

    Science.gov (United States)

    Nguyen, Huy Tu; Isaacowitz, Derek M; Rubin, Peter A D

    2009-02-01

    To investigate the facial cues that are used when making judgments about how old or tired a face appears. Experimental study. Forty-seven subjects: 15 male and 32 female participants, ranging from age 18 to 30 years. Forty-eight full-face digital images of "normal-appearing" patients were collected and uploaded to an eye-tracking system. We used an Applied Science Laboratories (Bedford, MA) Eye Tracker device associated with gaze-tracking software to record and calculate the gaze and fixation of the participants' left eye as they viewed images on a computer screen. After seeing each picture, participants were asked to assess the age of the face in the picture by making a selection on a rating scale divided into 5-year intervals; for fatigue judgments we used a rating scale from 1 (not tired) to 7 (most tired). The main outcome measure was gaze fixation, as assessed by tracking the eye movements of participants as they viewed full-face digital pictures. For fatigue judgments, participants spent the most time looking at the eye region (31.81%), then the forehead and the nose regions (14.99% and 14.12%, respectively); in the eye region, participants looked most at the brows (13.1%) and lower lids (9.4%). Participants spent more time looking at the cheeks on faces they rated as least tired than they did on those they rated as most tired (t = 2.079, Peye region (27.22%) and then the forehead (15.71%) and the nose (14.30%) had the highest frequencies of interest; in the eye region, the brows and lower lids also had the highest frequencies of interest (11.40% and 8.90%, respectively). Participants looked more at the brows (t = -2.63, Peye region. Consequently, these results suggest that aesthetic or functional surgery to the eye region may be one of the most effective interventions in enhancing the appearance of an individual. The author(s) have no proprietary or commercial interest in any materials discussed in this article.

  5. A Pilot Study: The Efficacy of Virgin Coconut Oil as Ocular Rewetting Agent on Rabbit Eyes

    Directory of Open Access Journals (Sweden)

    Haliza Abdul Mutalib

    2015-01-01

    Full Text Available Purpose. An open-label pilot study of virgin coconut oil (VCO was conducted to determine the safety of the agent as ocular rewetting eye drops on rabbits. Methods. Efficacy of the VCO was assessed by measuring NIBUT, anterior eye assessment, corneal staining, pH, and Schirmer value before instillation and at 30 min, 60 min, and two weeks after instillation. Friedman test was used to analyse any changes in all the measurable variables over the period of time. Results. Only conjunctival redness with instillation of saline agent showed significant difference over the period of time (P0.05. There were no changes in the NIBUT, limbal redness, palpebral conjunctiva redness, corneal staining, pH, and Schirmer value over the period of time for each agent (P>0.05. Conclusion. VCO acts as safe rewetting eye drops as it has shown no significant difference in the measurable parameter compared to commercial brand eye drops and saline. These study data suggest that VCO is safe to be used as ocular rewetting agent on human being.

  6. The acquisition of reading fluency in an orthographically transparent language (Italian): an eye movement longitudinal study.

    Science.gov (United States)

    De Luca, Maria; Zeri, Fabrizio; Spinelli, Donatella; Zoccolotti, Pierluigi

    2010-03-01

    The aim of this study was to examine longitudinally the acquisition of reading fluency in a shallow orthography from the very beginning using eye movement recordings. The development of reading fluency is easier to examine in shallow (such as German, Finnish, or Italian) rather than in opaque (such as English or French) orthographies because the former limit the presence of speed-accuracy trade-offs at early stages of acquisition. To date, only cross-sectional eye movement studies of reading development are available. One normally developing child was assessed at the very beginning of first grade and at the end of the first, second, and fifth grades. Eye movement parameters during reading, reading speed and accuracy in a standard reading test, and vocal reaction time at onset to single words varying in length were measured. Reading fluency improved dramatically during the first grade and progressively less thereafter: the word-length effect decreased abruptly by the end of the first grade and then less onwards. The rate of improvement closely followed a power function. This pattern held for standard reading tests, various eye movement parameters during reading, and vocal reaction times to single word onset. These longitudinal observations indicate the rapid acquisition of reading fluency in a transparent orthography showing that the largest changes occurred within the first year of education.

  7. A Pilot Study: The Efficacy of Virgin Coconut Oil as Ocular Rewetting Agent on Rabbit Eyes

    Science.gov (United States)

    Mutalib, Haliza Abdul; Kaur, Sharanjeet; Ghazali, Ahmad Rohi; Chinn Hooi, Ng; Safie, Nor Hasanah

    2015-01-01

    Purpose. An open-label pilot study of virgin coconut oil (VCO) was conducted to determine the safety of the agent as ocular rewetting eye drops on rabbits. Methods. Efficacy of the VCO was assessed by measuring NIBUT, anterior eye assessment, corneal staining, pH, and Schirmer value before instillation and at 30 min, 60 min, and two weeks after instillation. Friedman test was used to analyse any changes in all the measurable variables over the period of time. Results. Only conjunctival redness with instillation of saline agent showed significant difference over the period of time (P 0.05). There were no changes in the NIBUT, limbal redness, palpebral conjunctiva redness, corneal staining, pH, and Schirmer value over the period of time for each agent (P > 0.05). Conclusion. VCO acts as safe rewetting eye drops as it has shown no significant difference in the measurable parameter compared to commercial brand eye drops and saline. These study data suggest that VCO is safe to be used as ocular rewetting agent on human being. PMID:25802534

  8. A pilot study: the efficacy of virgin coconut oil as ocular rewetting agent on rabbit eyes.

    Science.gov (United States)

    Mutalib, Haliza Abdul; Kaur, Sharanjeet; Ghazali, Ahmad Rohi; Chinn Hooi, Ng; Safie, Nor Hasanah

    2015-01-01

    Purpose. An open-label pilot study of virgin coconut oil (VCO) was conducted to determine the safety of the agent as ocular rewetting eye drops on rabbits. Methods. Efficacy of the VCO was assessed by measuring NIBUT, anterior eye assessment, corneal staining, pH, and Schirmer value before instillation and at 30 min, 60 min, and two weeks after instillation. Friedman test was used to analyse any changes in all the measurable variables over the period of time. Results. Only conjunctival redness with instillation of saline agent showed significant difference over the period of time (P 0.05). There were no changes in the NIBUT, limbal redness, palpebral conjunctiva redness, corneal staining, pH, and Schirmer value over the period of time for each agent (P > 0.05). Conclusion. VCO acts as safe rewetting eye drops as it has shown no significant difference in the measurable parameter compared to commercial brand eye drops and saline. These study data suggest that VCO is safe to be used as ocular rewetting agent on human being.

  9. Through Queers' Eyes: Critical Educational Ethnography in Queer Studies

    Science.gov (United States)

    Chang, Yin-Kun

    2005-01-01

    In this paper, the author provides an overview of the theoretical background of critical educational research--namely, critical pedagogy--and discusses the relationship between critical pedagogy and queer issues. In doing this, the author addresses the current strengths and weaknesses of queer studies in education. The author suggests that making…

  10. Learning from Concept Mapping and Hypertext: An Eye Tracking Study

    Science.gov (United States)

    Amadieu, Franck; Salmerón, Ladislao; Cegarra, Julien; Paubel, Pierre-Vincent; Lemarié, Julie; Chevalier, Aline

    2015-01-01

    This study examined the effects of prior domain knowledge and learning sequences on learning with concept mapping and hypertext. Participants either made a concept map in a first step and then read the hypertext's contents combined with concept mapping (high activating condition), or they read the hypertext's contents first and then made a concept…

  11. A review on eye movement studies in childhood and adolescent psychiatry.

    NARCIS (Netherlands)

    Lambregts-Rommelse, N.N.J.; Stigchel, S Van der; Sergeant, J.A.

    2008-01-01

    The neural substrates of eye movement measures are largely known. Therefore, measurement of eye movements in psychiatric disorders may provide insight into the underlying neuropathology of these disorders. Visually guided saccades, antisaccades, memory guided saccades, and smooth pursuit eye movemen

  12. Twins eye study in Tasmania (TEST): rationale and methodology to recruit and examine twins.

    Science.gov (United States)

    Mackey, David A; Mackinnon, Jane R; Brown, Shayne A; Kearns, Lisa S; Ruddle, Jonathan B; Sanfilippo, Paul G; Sun, Cong; Hammond, Christopher J; Young, Terri L; Martin, Nicholas G; Hewitt, Alex W

    2009-10-01

    Visual impairment is a leading cause of morbidity and poor quality of life in our community. Unravelling the mechanisms underpinning important blinding diseases could allow preventative or curative steps to be implemented. Twin siblings provide a unique opportunity in biology to discover genes associated with numerous eye diseases and ocular biometry. Twins are particularly useful for quantitative trait analysis through genome-wide association and linkage studies. Although many studies involving twins rely on twin registries, we present our approach to the Twins Eye Study in Tasmania to provide insight into possible recruitment strategies, expected participation rates and potential examination strategies that can be considered by other researchers for similar studies. Five separate avenues for cohort recruitment were adopted: (1) piggy-backing existing studies where twins had been recruited, (2) utilizing the national twin registry, (3) word-of-mouth and local media publicity, (4) directly approaching schools, and finally (5) collaborating with other research groups studying twins.

  13. Seeing things through science eyes: A case study of an exemplary elementary teacher

    Science.gov (United States)

    Foster, Andrea Susan

    Science-eyed elementary teachers exhibit relentless passions for replacing traditional teaching with realistic, integrated, responsible instruction with science at its core. The purpose of this study was to explore an exemplary elementary teacher's thinking about science and how it serves as a vehicle for the learning that occurs in her primary classroom. Two research questions were investigated in this study. First, what does it mean for an exemplary elementary teacher to view all learning with science eyes? Second, in what ways does the science-oriented elementary teacher use her knowledge of science content, pedagogy, and practical experience to structure her students' learning and her classroom teaching? A naturalistic methodology was employed in this research effort. Classroom observations, teacher interviews, documents, and selected artifacts were analyzed using a constant comparative method (Glaser & Strauss, 1967; Lincoln & Guba, 1985) and the analysis tools of HyperRESEARCH (1994) in an effort to unravel the complex, intuitive knowledge of a nationally recognized first grade teacher. Data analyses provided insightful information about this exceptional teacher and how she organizes, plans, and implements effective lessons that integrate science with all subject areas. Four direct observation themes, Best Practice, Just Like a Scientist, Integrating Curriculum - A Balancing Act, and Expert Pedagogy, and six interview themes, Curriculum - What to Teach?, Instruction - How to Teach, Knowing Students, Getting Stuff, Professionalism, and Reflective Practitioner, emerged from independent analyses of two data sets. Three overall themes, Head, Heart, and Hands of an Exemplary Science Elementary Teacher, emerged from a convergent content analysis. The themes provide the foundation for a proposed model of an expert science pedagogue. Ten portrait-like, impressionistic, vignettes are included in this unique study to capture the spirit of the science-eyed elementary

  14. Ocular Trauma in a Rural Population of North China:The Handan Eye Study

    Institute of Scientific and Technical Information of China (English)

    ZHOU Jun; WANG Feng Hua; LU Hai; LIANG Yuan Bo; WANG Ning Li; the Handan Eye StudYGroup

    2015-01-01

    Objective To determine the prevalence of ocular trauma and the proportion of blindness and visual impairment due to trauma in a rural population in northern China. Methods The Handan Eye Study is a population-based cross-sectional study that surveyed 6830 Chinese people aged 30+years from 13 randomly selected villages in Yongnian County, city of Handan, Hebei Province, in July, 2006. All participants underwent a standardized interview and extensive examinations. A structured questionnaire was used to collect information on ocular trauma. Results Of the 5837 participants who filled out the questionnaire, 124 subjects [2.1%;95%confidence interval (CI), 1.8%-2.5%] reported a history of ocular trauma in either eye, including 19 (0.3%) persons reporting trauma in both eyes. Men were more likely to have an eye injury than women [odds ratio (OR), 3.3;2.2-4.9]. In multiple logistic regression models, ocular trauma was significantly more frequent among normotensive participants when compared with hypertensive participants (hypertensive vs. normotensive:OR, 0.6;0.4-0.9) and among participants who had a history of falls (OR, 2.4;1.2-4.8). The proportion of unilateral visual impairment and unilateral blindness due to trauma were 10.5% (13 subjects) and 21.0%(26 subjects), respectively. Conclusion Our study reports the prevalence of severe ocular trauma among adults in rural China, revealing a high proportion of blindness and visual impairment due to trauma. These findings suggest the need for educational strategies to increase eye health awareness in this rural population with focus on providing at least appropriate first aid care to reduce blindness due to trauma.

  15. Eye contact perception in the West and East: a cross-cultural study.

    Directory of Open Access Journals (Sweden)

    Shota Uono

    Full Text Available This study investigated whether eye contact perception differs in people with different cultural backgrounds. Finnish (European and Japanese (East Asian participants were asked to determine whether Finnish and Japanese neutral faces with various gaze directions were looking at them. Further, participants rated the face stimuli for emotion and other affect-related dimensions. The results indicated that Finnish viewers had a smaller bias toward judging slightly averted gazes as directed at them when judging Finnish rather than Japanese faces, while the bias of Japanese viewers did not differ between faces from their own and other cultural backgrounds. This may be explained by Westerners experiencing more eye contact in their daily life leading to larger visual experience of gaze perception generally, and to more accurate perception of eye contact with people from their own cultural background particularly. The results also revealed cultural differences in the perception of emotion from neutral faces that could also contribute to the bias in eye contact perception.

  16. Eye-tracking in amyotrophic lateral sclerosis: A longitudinal study of saccadic and cognitive tasks.

    Science.gov (United States)

    Proudfoot, Malcolm; Menke, Ricarda A L; Sharma, Rakesh; Berna, Claire M; Hicks, Stephen L; Kennard, Christopher; Talbot, Kevin; Turner, Martin R

    2015-01-01

    A relative preservation of eye movements is notable in ALS, but saccadic functions have not been studied longitudinally. ALS overlaps with FTD, typically involving executive dysfunction, and eye-tracking offers additional potential for the assessment of extramotor pathology where writing and speaking are both impaired. Eye-tracking measures (including anti-saccade, trail-making and visual search tasks) were assessed at six-monthly intervals for up to two years in a group of ALS (n = 61) and primary lateral sclerosis (n = 7) patients, compared to healthy age-matched controls (n = 39) assessed on a single occasion. Task performance was explored speculatively in relation to resting-state functional MRI (R-FMRI) network connectivity. Results showed that ALS patients were impaired on executive and visual search tasks despite normal basic saccadic function, and impairments in the PLS patients were unexpectedly often more severe. No significant progression was detected longitudinally in either group. No changes in R-FMRI network connectivity were identified in relation to patient performance. In conclusion, eye-tracking offers an objective means to assess extramotor cerebral involvement in ALS. The relative resistance of pure oculomotor function is confirmed, and higher-level executive impairments do not follow the same rate of decline as physical disability. PLS patients may have more cortical dysfunction than has been previously appreciated.

  17. Objective method for evaluating orthodontic treatment from the lay perspective: An eye-tracking study.

    Science.gov (United States)

    Wang, Xi; Cai, Bin; Cao, Yang; Zhou, Chen; Yang, Le; Liu, Runzhong; Long, Xiaojing; Wang, Weicai; Gao, Dingguo; Bao, Baicheng

    2016-10-01

    Currently, few methods are available to measure orthodontic treatment need and treatment outcome from the lay perspective. The objective of this study was to explore the function of an eye-tracking method to evaluate orthodontic treatment need and treatment outcome from the lay perspective as a novel and objective way when compared with traditional assessments. The scanpaths of 88 laypersons observing the repose and smiling photographs of normal subjects and pretreatment and posttreatment malocclusion patients were recorded by an eye-tracking device. The total fixation time and the first fixation time on the areas of interest (eyes, nose, and mouth) for each group of faces were compared and analyzed using mixed-effects linear regression and a support vector machine. The aesthetic component of the Index of Orthodontic Treatment Need was used to categorize treatment need and outcome levels to determine the accuracy of the support vector machine in identifying these variables. Significant deviations in the scanpaths of laypersons viewing pretreatment smiling faces were noted, with less fixation time (P eye-tracking device was able to objectively quantify the effect of malocclusion on facial perception and the impact of orthodontic treatment on malocclusion from the lay perspective. The support vector machine for classification of selected features achieved high accuracy of judging treatment need and treatment outcome. This approach may represent a new method for objectively evaluating orthodontic treatment need and treatment outcome from the perspective of laypersons. Copyright © 2016 American Association of Orthodontists. Published by Elsevier Inc. All rights reserved.

  18. Classroom Misbehavior in the Eyes of Students: A Qualitative Study

    Directory of Open Access Journals (Sweden)

    Rachel C. F. Sun

    2012-01-01

    Full Text Available Using individual interviews, this study investigated perceptions of classroom misbehaviors among secondary school students in Hong Kong (N=18. Nineteen categories of classroom misbehaviors were identified, with talking out of turn, disrespecting teacher, and doing something in private being most frequently mentioned. Findings revealed that students tended to perceive misbehaviors as those actions inappropriate in the classroom settings and even disrupting teachers' teaching and other students' learning. Among various misbehaviors, talking out of turn and disrespecting teacher were seen as the most disruptive and unacceptable. These misbehaviors were unacceptable because they disturbed teaching and learning, and violated the values of respect, conformity, and obedience in the teacher-student relationship within the classroom. The frequency and intensity of misbehaviors would escalate if students found it fun, no punishment for such misbehaviors, or teachers were not authoritative enough in controlling the situations. Implications for further research and classroom management are discussed.

  19. Classroom misbehavior in the eyes of students: a qualitative study.

    Science.gov (United States)

    Sun, Rachel C F; Shek, Daniel T L

    2012-01-01

    Using individual interviews, this study investigated perceptions of classroom misbehaviors among secondary school students in Hong Kong (N = 18). Nineteen categories of classroom misbehaviors were identified, with talking out of turn, disrespecting teacher, and doing something in private being most frequently mentioned. Findings revealed that students tended to perceive misbehaviors as those actions inappropriate in the classroom settings and even disrupting teachers' teaching and other students' learning. Among various misbehaviors, talking out of turn and disrespecting teacher were seen as the most disruptive and unacceptable. These misbehaviors were unacceptable because they disturbed teaching and learning, and violated the values of respect, conformity, and obedience in the teacher-student relationship within the classroom. The frequency and intensity of misbehaviors would escalate if students found it fun, no punishment for such misbehaviors, or teachers were not authoritative enough in controlling the situations. Implications for further research and classroom management are discussed.

  20. Eye Movement Training and Suggested Gaze Strategies in Tunnel Vision - A Randomized and Controlled Pilot Study.

    Science.gov (United States)

    Ivanov, Iliya V; Mackeben, Manfred; Vollmer, Annika; Martus, Peter; Nguyen, Nhung X; Trauzettel-Klosinski, Susanne

    2016-01-01

    Degenerative retinal diseases, especially retinitis pigmentosa (RP), lead to severe peripheral visual field loss (tunnel vision), which impairs mobility. The lack of peripheral information leads to fewer horizontal eye movements and, thus, diminished scanning in RP patients in a natural environment walking task. This randomized controlled study aimed to improve mobility and the dynamic visual field by applying a compensatory Exploratory Saccadic Training (EST). Oculomotor responses during walking and avoiding obstacles in a controlled environment were studied before and after saccade or reading training in 25 RP patients. Eye movements were recorded using a mobile infrared eye tracker (Tobii glasses) that measured a range of spatial and temporal variables. Patients were randomly assigned to two training conditions: Saccade (experimental) and reading (control) training. All subjects who first performed reading training underwent experimental training later (waiting list control group). To assess the effect of training on subjects, we measured performance in the training task and the following outcome variables related to daily life: Response Time (RT) during exploratory saccade training, Percent Preferred Walking Speed (PPWS), the number of collisions with obstacles, eye position variability, fixation duration, and the total number of fixations including the ones in the subjects' blind area of the visual field. In the saccade training group, RTs on average decreased, while the PPWS significantly increased. The improvement persisted, as tested 6 weeks after the end of the training. On average, the eye movement range of RP patients before and after training was similar to that of healthy observers. In both, the experimental and reading training groups, we found many fixations outside the subjects' seeing visual field before and after training. The average fixation duration was significantly shorter after the training, but only in the experimental training condition

  1. How dogs scan familiar and inverted faces: an eye movement study.

    Science.gov (United States)

    Somppi, Sanni; Törnqvist, Heini; Hänninen, Laura; Krause, Christina M; Vainio, Outi

    2014-05-01

    Faces play an important role in communication and identity recognition in social animals. Domestic dogs often respond to human facial cues, but their face processing is weakly understood. In this study, facial inversion effect (deficits in face processing when the image is turned upside down) and responses to personal familiarity were tested using eye movement tracking. A total of 23 pet dogs and eight kennel dogs were compared to establish the effects of life experiences on their scanning behavior. All dogs preferred conspecific faces and showed great interest in the eye area, suggesting that they perceived images representing faces. Dogs fixated at the upright faces as long as the inverted faces, but the eye area of upright faces gathered longer total duration and greater relative fixation duration than the eye area of inverted stimuli, regardless of the species (dog or human) shown in the image. Personally, familiar faces and eyes attracted more fixations than the strange ones, suggesting that dogs are likely to recognize conspecific and human faces in photographs. The results imply that face scanning in dogs is guided not only by the physical properties of images, but also by semantic factors. In conclusion, in a free-viewing task, dogs seem to target their fixations at naturally salient and familiar items. Facial images were generally more attractive for pet dogs than kennel dogs, but living environment did not affect conspecific preference or inversion and familiarity responses, suggesting that the basic mechanisms of face processing in dogs could be hardwired or might develop under limited exposure.

  2. Optics of the human cornea influence the accuracy of stereo eye-tracking methods: a simulation study

    NARCIS (Netherlands)

    Barsingerhorn, A.D.; Boonstra, F.N.; Goossens, H.H.L.M.

    2017-01-01

    Current stereo eye-tracking methods model the cornea as a sphere with one refractive surface. However, the human cornea is slightly aspheric and has two refractive surfaces. Here we used ray-tracing and the Navarro eye-model to study how these optical properties affect the accuracy of different

  3. Individual Differences in Fifth Graders' Literacy and Academic Language Predict Comprehension Monitoring Development: An Eye-Movement Study

    Science.gov (United States)

    Connor, Carol McDonald; Radach, Ralph; Vorstius, Christian; Day, Stephanie L.; McLean, Leigh; Morrison, Frederick J.

    2015-01-01

    In this study, we investigated fifth graders' (n = 52) fall literacy, academic language, and motivation and how these skills predicted fall and spring comprehension monitoring on an eye movement task. Comprehension monitoring was defined as the identification and repair of misunderstandings when reading text. In the eye movement task, children…

  4. In vivo, Ex Vivo, and In Vitro Approaches to Study Intermediate Filaments in the Eye Lens.

    Science.gov (United States)

    Jarrin, Miguel; Young, Laura; Wu, Weiju; Girkin, John M; Quinlan, Roy A

    2016-01-01

    The role of the eye lens is to focus light into the retina. To perform this unique function, the ocular lens must be transparent. Previous studies have demonstrated the expression of vimentin, BFSP1, and BFSP2 in the eye lens. These intermediate filament (IF) proteins are essential to the optical properties of the lens. They are also important to its biomechanical properties, to the shape of the lens fiber cells, and to the organization and function of the plasma membrane. The eye lens is an iconic model in developmental studies, as a result different vertebrate models, including zebrafish, have been developed to study lens formation. In the present chapter, we have summarized the new approaches and the more breakthrough models (e.g., iPSc) that can be used to study the function of IFs in the ocular lens. We have presented three different groups of models. The first group includes in vitro models, where IFs can be studied and manipulated in lens cell cultures. The second includes ex vivo models. These replicate better the complex lens cell differentiation processes and the role(s) played by IFs. The third class is the in vivo models, and here, we have focused on Zebrafish and new imaging approaches using selective plane illumination microscopy. Finally, we present protocols on how to use these lens models to study IFs.

  5. An Eye-tracking Study of Notational, Informational, and Emotional Aspects of Learning Analytics Representations

    DEFF Research Database (Denmark)

    Vatrapu, Ravi; Reimann, Peter; Bull, Susan;

    2013-01-01

    This paper presents an eye-tracking study of notational, informational, and emotional aspects of nine different notational systems (Skill Meters, Smilies, Traffic Lights, Topic Boxes, Collective Histograms, Word Clouds, Textual Descriptors, Table, and Matrix) and three different information state...... of learning analytics representations and discourse environments are discussed....... (Weak, Average, & Strong) used to represent student's learning. Findings from the eye-tracking study show that higher emotional activation was observed for the metaphorical notations of traffic lights and smilies and collective representations. Mean view time was higher for representations...... of the "average" informational learning state. Qualitative data analysis of the think-aloud comments and post-study interview show that student participants reflected on the meaning-making opportunities and action-taking possibilities afforded by the representations. Implications for the design and evaluation...

  6. Evaluation of Color Settings in Aerial Images with the Use of Eye-Tracking User Study

    Science.gov (United States)

    Mirijovsky, J.; Popelka, S.

    2016-06-01

    The main aim of presented paper is to find the most realistic and preferred color settings for four different types of surfaces on the aerial images. This will be achieved through user study with the use of eye-movement recording. Aerial images taken by the unmanned aerial system were used as stimuli. From each image, squared crop area containing one of the studied types of surfaces (asphalt, concrete, water, soil, and grass) was selected. For each type of surface, the real value of reflectance was found with the use of precise spectroradiometer ASD HandHeld 2 which measures the reflectance. The device was used at the same time as aerial images were captured, so lighting conditions and state of vegetation were equal. The spectral resolution of the ASD device is better than 3.0 nm. For defining the RGB values of selected type of surface, the spectral reflectance values recorded by the device were merged into wider groups. Finally, we get three groups corresponding to RGB color system. Captured images were edited with the graphic editor Photoshop CS6. Contrast, clarity, and brightness were edited for all surface types on images. Finally, we get a set of 12 images of the same area with different color settings. These images were put into the grid and used as stimuli for the eye-tracking experiment. Eye-tracking is one of the methods of usability studies and it is considered as relatively objective. Eye-tracker SMI RED 250 with the sampling frequency 250 Hz was used in the study. As respondents, a group of 24 students of Geoinformatics and Geography was used. Their task was to select which image in the grid has the best color settings. The next task was to select which color settings they prefer. Respondents' answers were evaluated and the most realistic and most preferable color settings were found. The advantage of the eye-tracking evaluation was that also the process of the selection of the answers was analyzed. Areas of Interest were marked around each image in the

  7. Experimental pain induces attentional bias that is modified by enhanced motivation: An eye tracking study.

    Science.gov (United States)

    Sun, Z-K; Wang, J-Y; Luo, F

    2016-09-01

    In this study, the effects of prior pain experience and motivation on attentional bias towards pain-related information were investigated within two visual-probe tasks via eye movement behaviours. It is hypothesized that pain experience would induce stronger attentional bias and such bias could be suppressed by the motivation to avoid impeding pain. All participants took part in visual-probe tasks with pictures and words as stimuli that are typically used in studies of attentional bias. They were allocated to three groups: no-pain (NP) group, performing tasks without experiencing pain; pain-experience (PE) group, performing the same tasks following painful stimuli; and pain-experience-with-motivation (PEM) group, undergoing the same procedure as PE group with additional instructions about avoiding impeding pain. Eye movements were recorded during the tasks. The eye movement data showed that: (1) participants in the PE group exhibited stronger attention bias towards painful pictures than those in the NP group; (2) the attentional bias towards painful pictures was significantly reduced in the PEM group as compared to the PE group. By contrast, the verbal task failed to find these effects using sensory pain words as stimuli. This study was the first that revealed the impact of acute experimental pain on attentional bias towards pain-related information in healthy individuals through eye tracking. It may provide a possible solution to reduce hypervigilance towards pain-related information by altering the motivational relevance. WHAT DOES THIS STUDY ADD?: (1) This study revealed the impact of experimental pain on attentional bias in healthy individuals; (2) This study may provide a possible approach of altering motivational relevance to control the pain-induced attentional bias towards pain-related information. © 2016 European Pain Federation - EFIC®

  8. A clinical study on "Computer vision syndrome" and its management with Triphala eye drops and Saptamrita Lauha.

    Science.gov (United States)

    Gangamma, M P; Poonam; Rajagopala, Manjusha

    2010-04-01

    American Optometric Association (AOA) defines computer vision syndrome (CVS) as "Complex of eye and vision problems related to near work, which are experienced during or related to computer use". Most studies indicate that Video Display Terminal (VDT) operators report more eye related problems than non-VDT office workers. The causes for the inefficiencies and the visual symptoms are a combination of individual visual problems and poor office ergonomics. In this clinical study on "CVS", 151 patients were registered, out of whom 141 completed the treatment. In Group A, 45 patients had been prescribed Triphala eye drops; in Group B, 53 patients had been prescribed the Triphala eye drops and SaptamritaLauha tablets internally, and in Group C, 43 patients had been prescribed the placebo eye drops and placebo tablets. In total, marked improvement was observed in 48.89, 54.71 and 06.98% patients in groups A, B and C, respectively.

  9. Attitude Determination and Control Subsystem (ADCS) Preparations for the EPOXI Flyby of Comet Hartley 2

    Science.gov (United States)

    Luna, Michael E.; Collins, Steven M.

    2011-01-01

    On November 4, 2010 the former "Deep Impact" spacecraft, renamed "EPOXI" for its extended mission, flew within 700km of comet 103P/Hartley 2. In July 2005, the spacecraft had previously imaged a probe impact of comet Tempel 1. The EPOXI flyby was the fifth close encounter of a spacecraft with a comet nucleus and marked the first time in history that two comet nuclei were imaged at close range with the same suite of onboard science instruments. This challenging objective made the function of the attitude determination and control subsystem (ADCS) critical to the successful execution of the EPOXI flyby.As part of the spacecraft flyby preparations, the ADCS operations team had to perform meticulous sequence reviews, implement complex spacecraft engineering and science activities and perform numerous onboard calibrations. ADCS contributions included design and execution of 10 trajectory correction maneuvers, the science calibration of the two telescopic instruments, an in-flight demonstration of high-rate turns between Earth and comet point, and an ongoing assessment of reaction wheel health. The ADCS team was also responsible for command sequences that included updates to the onboard ephemeris and sun sensor coefficients and implementation of reaction wheel assembly (RWA) de-saturations.

  10. PARAMETER ESTIMATION OF VSI FED PERMANENT MAGNET SYNCHRONOUS MOTOR BY USING HARTLEY MODULATING FUNCTION

    Directory of Open Access Journals (Sweden)

    P. Ramana

    2011-08-01

    Full Text Available This paper discusses modeling and parameter estimation of PMSM. The design of a control system for a high performance drive requires a mathematical model of the motor. This is usually derived fromphysical principles, then the parameters of the motor are determined through off-line testing or estimated on-line from input/output operating records data. The dynamics of synchronous motor can be described by a set of differential equations relating voltages, currents, speed and torque. The equations represented in d-q axes variables in the rotor reference frame using park’s transformation are presented. A parameter estimation technique employing the Hartley modulating function (HMF is detailed. Using the data obtained from open loop simulation physical parameters such as stator resistance andinductances as well as mechanical parameters such as moment of inertia and viscous friction coefficient have been estimated with a fair amount of accuracy. This estimate has been found to be quite sensitive to the choice of sampling period.

  11. WISE/NEOWISE observations of comet 103P/Hartley 2

    CERN Document Server

    Bauer, James M; Mainzer, A K; Masiero, Joseph R; Grav, Tommy; Dailey, John W; McMillan, Robert S; Lisse, Carey M; Fernández, Yan R; Meech, Karen J; Pittichova, Jana; Blauvelt, Erin K; Masci, Frank J; A'Hearn, Michael F; Cutri, Roc M; Scotti, James V; Tholen, David J; DeBaun, Emily; Wilkins, Ashlee; Hand, Emma; Wright, Edward L

    2011-01-01

    We report results based on mid-infrared photometry of comet 103P/Hartley 2 taken during May 4-13, 2010 (when the comet was at a heliocentric distance of 2.3 AU, and an observer distance of 2.0 AU) by the Wide-field Infrared Survey Explorer (Wright et al. 2010). Photometry of the coma at 22 microns and data from the University of Hawaii 2.2-m telescope obtained on May 22, 2010 provide constraints on the dust particle size distribution, dlogn/dlogm, yielding power-law slope values of alpha = -0.97 +/- 0.10, steeper than that found for the inbound particle fluence during the Stardust encounter of comet 81P/Wild 2 (Green et al. 2004). The extracted nucleus signal at 12 microns is consistent with a body of average spherical radius of 0.6 +/- 0.2 km (one standard deviation), assuming a beaming parameter of 1.2. The 4.6 micron-band signal in excess of dust and nucleus reflected and thermal contributions may be attributed to carbon monoxide or carbon dioxide emission lines and provides limits and estimates of species...

  12. Characterizing the Large (cm-size) Grains Around Comet 103P/Hartley 2

    Science.gov (United States)

    Sunshine, Jessica M.; Feaga, Lori M.; Farnham, Tony; Protopapa, Silvia; Kelley, Michael S.; Engle, Anna

    2016-10-01

    During the flyby of comet 103P/Hartley 2, two populations of bright grains were identified in the coma. Small, 1 µm-sized, water ice-rich grains were observed near the small end of the nucleus that were dragged from the interior by CO2 gas emissions. At closest approach a population of larger grains was clearly seen in visible images off the large lobe. The estimated brightness of the isolated grains suggests that they are likely cm-sized particles and likely water ice-rich. Both sets of grains were simultaneously observed in visible images, at two different resolutions, and by Deep Impact infrared spectrometer. However, because of the difficulty in finding isolated grains in the infrared slit, the population of larger grains has not previously been characterized. Doing so allows us to determine both the reflected and thermal properties of the grains, which when compared to visible images can be used to constrain the size of the grains. Their spectral properties can also be used to definitively detect water ice as has been assumed from visible albedos. In addition, the infrared spectra can be used estimate the relative abundance and particle sizes of ice and non-ice components. The velocity and dynamics of these larger grains can also be characterized. These data will be compared with those of the population of smaller grains emanated directly from the nucleus.Funding from NASA'S Discovery Data Analysis Program (NNX16AJ93G) is greatfully acknowledged.

  13. Attitude Determination and Control Subsystem (ADCS) Preparations for the EPOXI Flyby of Comet Hartley 2

    Science.gov (United States)

    Luna, Michael E.; Collins, Steven M.

    2011-01-01

    On November 4, 2010 the former "Deep Impact" spacecraft, renamed "EPOXI" for its extended mission, flew within 700km of comet 103P/Hartley 2. In July 2005, the spacecraft had previously imaged a probe impact of comet Tempel 1. The EPOXI flyby was the fifth close encounter of a spacecraft with a comet nucleus and marked the first time in history that two comet nuclei were imaged at close range with the same suite of onboard science instruments. This challenging objective made the function of the attitude determination and control subsystem (ADCS) critical to the successful execution of the EPOXI flyby.As part of the spacecraft flyby preparations, the ADCS operations team had to perform meticulous sequence reviews, implement complex spacecraft engineering and science activities and perform numerous onboard calibrations. ADCS contributions included design and execution of 10 trajectory correction maneuvers, the science calibration of the two telescopic instruments, an in-flight demonstration of high-rate turns between Earth and comet point, and an ongoing assessment of reaction wheel health. The ADCS team was also responsible for command sequences that included updates to the onboard ephemeris and sun sensor coefficients and implementation of reaction wheel assembly (RWA) de-saturations.

  14. A Distribution of Large Particles in the Coma of Comet 103P/Hartley 2

    CERN Document Server

    Kelley, Michael S; Bodewits, Dennis; A'Hearn, Michael F; Lisse, Carey M; Kolokolova, Ludmilla; Kissel, Jochen; Hermalyn, Brendan; 10.1016/j.icarus.2012.09.037

    2013-01-01

    The coma of comet 103P/Hartley 2 has a significant population of large particles observed as point sources in images taken by the Deep Impact spacecraft. We measure their spatial and flux distributions, and attempt to constrain their composition. The flux distribution of these particles implies a very steep size distribution with power-law slopes ranging from -6.6 to -4.7. The radii of the particles extend up to 20 cm, and perhaps up to 2 m, but their exact sizes depend on their unknown light scattering properties. We consider two cases: bright icy material, and dark dusty material. The icy case better describes the particles if water sublimation from the particles causes a significant rocket force, which we propose as the best method to account for the observed spatial distribution. Solar radiation is a plausible alternative, but only if the particles are very low density aggregates. If we treat the particles as mini-nuclei, we estimate they account for <16-80% of the comet's total water production rate (...

  15. Ground-based Multiwavelength Observations of Comet 103P/Hartley 2

    CERN Document Server

    Gicquel, A; Villanueva, G L; Remijan, A J; Coulson, I M; Chuang, Y -L; Charnley, S B; Cordiner, M A; Kuan, Y -J

    2014-01-01

    The Jupiter-family comet 103P/Hartley 2 (103P) was the target of the NASA EPOXI mission. In support of this mission, we conducted observations from radio to submillimeter wavelengths of comet 103P in the three weeks preceding the spacecraft rendezvous on UT 2010 November 4.58. This time period included the passage at perihelion and the closest approach of the comet to the Earth. Here we report detections of HCN, H2CO, CS, and OH and upper limits for HNC and DCN towards 103P, using the Arizona Radio Observatory Kitt Peak 12m telescope (ARO 12m) and submillimeter telescope (SMT), the James Clerk Maxwell Telescope (JCMT) and the Greenbank Telescope (GBT). The water production rate, QH2O = (0.67 - 1.07) x 10^28 s^-1, was determined from the GBT OH data. From the average abundance ratios of HCN and H2CO relative to water (0.13 +/- 0.03 % and 0.14 +/- 0.03 %, respectively), we conclude that H2CO is depleted and HCN is normal with respect to typically-observed cometary mixing ratios. However, the abundance ratio of ...

  16. Eye Movement Studies on Word Recognition%词汇识别的眼动研究

    Institute of Scientific and Technical Information of China (English)

    周永垒; 任桂琴

    2011-01-01

    As an immediate measuring method,eye movement recording can monitor the subjects' behavior dynamically.From the perspectives of lexicon accesses with or without various interpretations,this thesis reviewed eye movement studies on word recognition,especially on the role of orthography and phonology in word access and analyzed and compared different views on the role of sentence context and relative meaning frequency in lexical ambiguity resolution.Based on previous studies,this thesis commented on the eye movement study features of word recognition investigations and the problems to be studied.%作为一种即时测量的研究手段,眼动方法可以动态地、同步地监控被试的阅读行为。从歧义词通达与非歧义词通达两个角度出发,对词汇识别过程中形、音的作用以及词汇歧义消解过程中语境、相对频率的作用等问题上存在的不同观点进行对比分析。在此基础上,分析总结词汇识别的眼动研究特点及有待于研究的问题。

  17. A novel treatment for keratitis sicca (Dry eye): Anatomical feasibility study.

    Science.gov (United States)

    Iwanaga, Joe; Watanabe, Koichi; Kusukawa, Jingo; Fisahn, Christian; Alonso, Fernando; Oskouian, Rod J; Tubbs, R Shane

    2017-09-01

    Chronic dry eye (keratitis sicca) is a significant problem that in certain populations can result in corneal desiccation and the potential for blindness. Therefore, novel treatments for such disorders might decrease patient morbidity. The present study aimed to investigate a potential treatment for chronic dry eye via a cadaveric feasibility study. On 10 cadaveric sides, the parotid gland branch of the auriculotemporal nerve (ATN) was identified and anastomosed to an anterior superficial temporal branch (STb) of this same nerve. The STb was then transposed anteriorly and sutured to the lacrimal gland. The parotid branch of the ATN was easily identified on all sides. The STb of the ATN was easily identified and mobilized on all sides. This latter nerve had adequate length to be moved to the ipsilateral lacrimal gland on all sides. Rerouting parotid gland secretomotor fibers to the superficial branch of the ATN and then moving this branch to the lacrimal gland is a feasible surgical maneuver based on our cadaveric study. Clinical studies are now necessary to show utility of this procedure in patients with chronic dry eye. Clin. Anat. 30:839-843, 2017. © 2017Wiley Periodicals, Inc. © 2017 Wiley Periodicals, Inc.

  18. Eye Injuries

    Science.gov (United States)

    The structure of your face helps protect your eyes from injury. Still, injuries can damage your eye, sometimes severely enough that you could lose your vision. Most eye injuries are preventable. If you play sports or ...

  19. Eye Wear

    Science.gov (United States)

    Eye wear protects or corrects your vision. Examples are Sunglasses Safety goggles Glasses (also called eyeglasses) Contact ... jobs and some sports carry a risk of eye injury. Thousands of children and adults get eye ...

  20. Eye Cancer

    Science.gov (United States)

    Cancer of the eye is uncommon. It can affect the outer parts of the eye, such as the eyelid, which are made up ... adults are melanoma and lymphoma. The most common eye cancer in children is retinoblastoma, which starts in ...

  1. Eye Diseases

    Science.gov (United States)

    ... the back of the eye Macular degeneration - a disease that destroys sharp, central vision Diabetic eye problems ... defense is to have regular checkups, because eye diseases do not always have symptoms. Early detection and ...

  2. Eye proprioception may provide real time eye position information.

    Science.gov (United States)

    Wang, Jing; Pan, Yujun

    2013-03-01

    Because of the frequency of eye movements, online knowledge of eye position is crucial for the accurate spatial perception and behavioral navigation. Both the internal monitoring signal (corollary discharge) of eye movements and the eye proprioception signal are thought to contribute to the localization of the eye position in the orbit. However, the functional role of these two eye position signals in spatial cognition has been disputed for more than a century. The predominant view proposes that the online analysis of eye position is exclusively provided by the corollary discharge signal, while the eye proprioception signal only plays a role in the long-term calibration of the oculomotor system. However, increasing evidence from recent behavioral and physiological studies suggests that the eye proprioception signal may play a role in the online monitoring of eye position. The purpose of this review is to discuss the feasibility and possible function of the eye proprioceptive signal for online monitoring of eye position.

  3. A clinical study of the efficacy of topical corticosteroids on dry eye

    OpenAIRE

    Yang, Chong-qing; Sun, Wen; Gu, Yang-Shun

    2006-01-01

    Objective: To evaluate the effect of topical corticosteroid for treatment of moderate or severe dry eye. Methods: Sixty eyes of 30 patients with moderate or severe dry eye, who were not sensitive to artificial tears, were treated with 0.1% fluorometholone eye drops. Subjective symptom and objective tests were used to evaluate the efficacy of treatment before and after application of 0.1% fluorometholone eye drops for 1 week and 1 month. Side effects were also evaluated. Results: After 1 week ...

  4. Analysis of Gnostic Actions Using Eye Tracking as a Method of Studying Insight in Problem Solving

    Directory of Open Access Journals (Sweden)

    Vladimirov I.Yu.,

    2016-04-01

    Full Text Available TThe paper focuses on the issue of research methods in studying insight. Since the process of insight is quite difficult to verbalize, researchers are presented with the methodological challenge of its objectifica- tion. One of the possible methods is the analysis of gnostic actions as components of a single integrated system of perceptive and thinking activity aimed at problem solving. The paper analyzes past and present periods in the explorations of insight with this method and suggests that eye tracking in problem solving is the most perspective technology. It reviews the studies of G. Knoblich, J. Ellis, E, Grant and M. Spivey, L. Thomas and A. Lleras, D. Kahneman, J.T. Wang and others. The paper compares various characteristics of eye movements and their content and discusses perspectives for the study on insight using the method of eye movement tracking, that is, testing the theoretical assumptions concerning the mechanisms of insight in problem solving and revealing the processes underlying insight.

  5. The disengagement of visual attention in Alzheimer's disease: a longitudinal eye-tracking study

    Science.gov (United States)

    Crawford, Trevor J.; Devereaux, Alex; Higham, Steve; Kelly, Claire

    2015-01-01

    Introduction: Eye tracking provides a convenient and promising biological marker of cognitive impairment in patients with neurodegenerative disease. Here we report a longitudinal study of saccadic eye movements in a sample of patients with Alzheimer's disease and elderly control participants who were assessed at the start of the study and followed up 12-months later. Methods: Eye movements were measured in the standard gap and overlap paradigms, to examine the longitudinal trends in the ability to disengage attention from a visual target. Results: Overall patients with Alzheimer's disease had slower reaction times than the control group. However, after 12-months, both groups showed faster and comparable reductions in reaction times to the gap, compared to the overlap stimulus. Interestingly, there was a general improvement for both groups with more accurately directed saccades and speeding of reaction times after 12-months. Conclusions: These findings point to the value of longer-term studies and follow-up assessment to ascertain the effects of dementia on oculomotor control. PMID:26157388

  6. The socialization effect on decision making in the Prisoner's Dilemma game: An eye-tracking study.

    Science.gov (United States)

    Peshkovskaya, Anastasia G; Babkina, Tatiana S; Myagkov, Mikhail G; Kulikov, Ivan A; Ekshova, Ksenia V; Harriff, Kyle

    2017-01-01

    We used a mobile eye-tracking system (in the form of glasses) to study the characteristics of visual perception in decision making in the Prisoner's Dilemma game. In each experiment, one of the 12 participants was equipped with eye-tracking glasses. The experiment was conducted in three stages: an anonymous Individual Game stage against a randomly chosen partner (one of the 12 other participants of the experiment); a Socialization stage, in which the participants were divided into two groups; and a Group Game stage, in which the participants played with partners in the groups. After each round, the respondent received information about his or her personal score in the last round and the overall winner of the game at the moment. The study proves that eye-tracking systems can be used for studying the process of decision making and forecasting. The total viewing time and the time of fixation on areas corresponding to noncooperative decisions is related to the participants' overall level of cooperation. The increase in the total viewing time and the time of fixation on the areas of noncooperative choice is due to a preference for noncooperative decisions and a decrease in the overall level of cooperation. The number of fixations on the group attributes is associated with group identity, but does not necessarily lead to cooperative behavior.

  7. The disengagement of visual attention in people with Alzheimer's Disease: A longitudinal eye-tracking study

    Directory of Open Access Journals (Sweden)

    Trevor J Crawford

    2015-06-01

    Full Text Available IntroductionEye tracking provides a convenient and promising biological marker of cognitive impairment in patients with neurodegenerative disease. Here we report a longitudinal study of saccadic eye movements in a sample of patients with dementia and elderly control participants who were assessed at start of the study and followed up 12 months later.MethodsEye movements were measured in the standard gap and overlap paradigms, to examine the longitudinal trends in the ability to disengage attention from a visual target.ResultsOverall patients with dementia had slower reaction times than the control group. However, after 12 months, both groups showed faster and comparable reductions in reaction times to the gap, compared to the overlap stimulus. Interestingly, there was a general improvement for both groups with more accurately directed saccades and speeding of reaction times after 12 months.ConclusionsThese findings point to the value of longer-term studies and follow-up assessment to ascertain the effects of dementia on oculomotor control.

  8. Optics of the human cornea influence the accuracy of stereo eye-tracking methods: a simulation study.

    Science.gov (United States)

    Barsingerhorn, A D; Boonstra, F N; Goossens, H H L M

    2017-02-01

    Current stereo eye-tracking methods model the cornea as a sphere with one refractive surface. However, the human cornea is slightly aspheric and has two refractive surfaces. Here we used ray-tracing and the Navarro eye-model to study how these optical properties affect the accuracy of different stereo eye-tracking methods. We found that pupil size, gaze direction and head position all influence the reconstruction of gaze. Resulting errors range between ± 1.0 degrees at best. This shows that stereo eye-tracking may be an option if reliable calibration is not possible, but the applied eye-model should account for the actual optics of the cornea.

  9. Physical activity in childhood and the association with myopia in adolescence – The CHAMPS Eye Study

    DEFF Research Database (Denmark)

    Lundberg, Lars Kristian; Vestergaard, Anders Højslet; Jacobsen, Nina

    Purpose: Myopia is the most frequent eye disease globally and is usually caused by increasing axial growth of the eye during childhood and adolescence. Lifestyle changes such as reduced physical activity (PA) are thought to be the driving force behind the rapid increase of myopia worldwide......-PA prompt a 0.3 mm longer AL (Pphysical activity was associated with a shorter axial length and refractive error for SED-PA and M-PA, consistent with theory....... cohort (Childhood Health, Activity, and Motor Performance School Study Denmark). PA was assessed with GT3X accelerometer (ActiGraph, Florida, USA) worn for 7 full consecutive days at the period August to October 2010: mean intensity was estimated as counts/min (CPM); and cut off-points for sedentary (SED...

  10. [Raman spectra study of thermal transformation of nephrite cat's eye from Sichuan province].

    Science.gov (United States)

    Lu, Bao-qi; Xia, Yi-ben; Qi, Li-jian; You, Jing-lin

    2005-11-01

    Raman spectrum and X-ray powder diffraction (XRD) were used to study the process andproduct of thermal transformation of nephrite cat's eye from Sichuan province. The results indicate that upon being heated till 900 degrees C, tremolite in the nephrite cat's eye is dehydrated completely and the appearance of a new characteristic band near 671 cm(-1) indicates the form of a new product. At 1 000 degrees C, the intensity of band near 1014 cm(-1) rises obviously, and the weak bands near 573 cm(-1) and 934 cm(-1) present. Up to 1100 degrees C, the band near 1033 cm(-1) appears. All these evidences show that the final thermal transformation product is identified as Ca-Mg pyroxene which is similar to diopside both in structure and in composition. This conclusion is confirmed by XRD.

  11. Prevalence and risk factors for visual impairment in preschool children the sydney paediatric eye disease study.

    Science.gov (United States)

    Pai, Amy Shih-I; Wang, Jie Jin; Samarawickrama, Chameen; Burlutsky, George; Rose, Kathryn A; Varma, Rohit; Wong, Tien Yin; Mitchell, Paul

    2011-08-01

    To assess the prevalence and associations of visual impairment (VI) in preschool children. Cross-sectional, population-based study. A total of 2461 children (73.8% participation rate), aged 6 to 72 months, were examined in the Sydney Paediatric Eye Disease Study during 2007-2009; of whom 1188, aged 30 to 72 months, with complete visual acuity (VA) data in both eyes, were included in this report. Measurement of VA was attempted on all children using the Electronic Visual Acuity (EVA) system or a logarithm of the minimum angle of resolution (logMAR) chart. Visual impairment was defined as presenting VA 0.05). Visual impairment in at least 1 eye was found in 6.4% of Australian preschool children, with bilateral VI found in 2.7%. Uncorrected refractive errors and amblyopia were the principal ocular conditions associated with VI. Low birthweight was a significant risk factor independent of age, gender, and ethnicity. The author(s) have no proprietary or commercial interest in any materials discussed in this article. Copyright © 2011 American Academy of Ophthalmology. Published by Elsevier Inc. All rights reserved.

  12. Visual exploration patterns of human figures in action: an eye tracker study with art paintings.

    Science.gov (United States)

    Villani, Daniela; Morganti, Francesca; Cipresso, Pietro; Ruggi, Simona; Riva, Giuseppe; Gilli, Gabriella

    2015-01-01

    Art exploration is a complex process conditioned by factors at different levels and includes both basic visual principles and complex cognitive factors. The human figure is considered a critical factor attracting the attention in art painting. Using an eye-tracking methodology, the goal of this study was to explore different elements of the human figure performing an action (face and body parts in action) in complex social scenes characterized by different levels of social interaction between agents depicted in scenes (individual vs. social). The sample included 44 laypersons, and the stimuli consisted of 10 fine art paintings representing the figurative style of classical art. The results revealed different scanning patterns of the human figure elements related to the level of social interaction of agents depicted in the scene. The agents' face attracted eye movements in social interaction scenes while the agents' body parts attracted eye movements only when the agents were involved in individual actions. These processes were confirmed specifically in participants with high empathic abilities who became immediately fixated on faces to develop a mimetic engagement with other agents. Future studies integrating other measures would help confirm the results obtained and strengthen their implication for embodiment processes.

  13. The Added Value of Eye-tracking in Diagnosing Dyscalculia: A Case Study

    Directory of Open Access Journals (Sweden)

    Sietske eVan Viersen

    2013-10-01

    Full Text Available The present study compared eye movements and performance of a nine-year-old girl with Developmental Dyscalculia (DD on a series of number line tasks to those of a group of typically developing (TD children (n = 10, in order to answer the question whether eye-tracking data from number line estimation tasks can be a useful tool to discriminate between TD children and children with a number processing deficit. Quantitative results indicated that the child with dyscalculia performed worse on all symbolic number line tasks compared to the control group, indicated by a low linear fit (R2 and a low accuracy measured by mean percent absolute error. In contrast to the control group, her magnitude representations seemed to be better represented by a logarithmic than a linear fit. Furthermore, qualitative analyses on the data of the child with dyscalculia revealed more unidentifiable fixation patterns in the processing of multi-digit numbers and more dysfunctional estimation strategy use in one third of the estimation trials as opposed to approximately 10% in the control group. In line with her dyscalculia diagnosis, these results confirm the difficulties with spatially representing and manipulating numerosities on a number line, resulting in inflexible and inadequate estimation or processing strategies. It can be concluded from this case study that eye-tracking data can be used to discern different number processing and estimation strategies in TD children and children with a number processing deficit. Hence, eye-tracking data in combination with number line estimation tasks might be a valuable and promising addition to current diagnostic measures.

  14. The added value of eye-tracking in diagnosing dyscalculia: a case study.

    Science.gov (United States)

    van Viersen, Sietske; Slot, Esther M; Kroesbergen, Evelyn H; Van't Noordende, Jaccoline E; Leseman, Paul P M

    2013-01-01

    The present study compared eye movements and performance of a 9-year-old girl with Developmental Dyscalculia (DD) on a series of number line tasks to those of a group of typically developing (TD) children (n = 10), in order to answer the question whether eye-tracking data from number line estimation tasks can be a useful tool to discriminate between TD children and children with a number processing deficit. Quantitative results indicated that the child with dyscalculia performed worse on all symbolic number line tasks compared to the control group, indicated by a low linear fit (R (2)) and a low accuracy measured by mean percent absolute error. In contrast to the control group, her magnitude representations seemed to be better represented by a logarithmic than a linear fit. Furthermore, qualitative analyses on the data of the child with dyscalculia revealed more unidentifiable fixation patterns in the processing of multi-digit numbers and more dysfunctional estimation strategy use in one third of the estimation trials as opposed to ~10% in the control group. In line with her dyscalculia diagnosis, these results confirm the difficulties with spatially representing and manipulating numerosities on a number line, resulting in inflexible and inadequate estimation or processing strategies. It can be concluded from this case study that eye-tracking data can be used to discern different number processing and estimation strategies in TD children and children with a number processing deficit. Hence, eye-tracking data in combination with number line estimation tasks might be a valuable and promising addition to current diagnostic measures.

  15. Measuring attentional bias in children with prominent ears: A prospective eye-tracking study.

    Science.gov (United States)

    Haworth, Rebecca; Sobey, Stephanie; Chorney, Jill M; Bezuhly, Michael; Hong, Paul

    2015-12-01

    When observing new faces, most people focus their attention on the central triangle of the face containing the eyes, nose and mouth. When viewing faces with prominent ears, observers may divert their attention from the central triangle. The objective of this study was to determine whether there was an objective attentional bias to prominent ears in comparison to non-prominent ears. A total of 24 naïve participants (13 female; mean age 22.88 years) viewed 15 photographs of children with bilateral prominent ears, unilateral prominent ears and non-prominent ears. Both pre- and post-otoplasty photographs of two patients were included. The eye movements of participants were recorded using the EyeLink 1000, a table-mounted eye-tracking device. Overall, the participants spent more time looking at the ear regions for faces with prominent ears in comparison to faces without prominent ears (p = 0.007, Z = -2.688). The attentional bias to the ear region of the patient who underwent bilateral otoplasty was significantly reduced in the post-operative photograph (p = 0.011, Z = -2.534). The patient who underwent unilateral otoplasty had no significant change in fixation times towards the ear region (p = 0.594, Z = -0.533). This study presents objective data to support the notion that observers show attentional bias to the ear region when viewing faces of children with prominent ears. The scope of this finding requires further research in both extent and impact. Copyright © 2015 British Association of Plastic, Reconstructive and Aesthetic Surgeons. Published by Elsevier Ltd. All rights reserved.

  16. Changes in intraocular pressure in study and fellow eyes in the IVAN trial

    Science.gov (United States)

    Foss, Alexander J E; Scott, Lauren J; Rogers, Chris A; Reeves, Barney C; Ghanchi, Faruque; Gibson, Jonathan; Chakravarthy, Usha

    2016-01-01

    Purpose To describe changes in intraocular pressure (IOP) in the ‘alternative treatments to Inhibit VEGF in Age-related choroidal Neovascularisation (IVAN)’ trial (registered as ISRCTN92166560). Design Randomised controlled clinical trial with factorial design. Participants Patients (n=610) with treatment naïve neovascular age-related macular degeneration were enrolled and randomly assigned to receive either ranibizumab or bevacizumab and to two regimens, namely monthly (continuous) or as needed (discontinuous) treatment. Methods At monthly visits, IOP was measured preinjection in both eyes, and postinjection in the study eye. Outcome measures The effects of 10 prespecified covariates on preinjection IOP, change in IOP (postinjection minus preinjection) and the difference in preinjection IOP between the two eyes were examined. Results For every month in trial, there was a statistically significant rise in both the preinjection IOP and the change in IOP postinjection during the time in the trial (estimate 0.02 mm Hg, 95% CI 0.01 to 0.03, p<0.001 and 0.03 mm Hg, 95% CI 0.01 to 0.04, p=0.002, respectively). There was also a small but significant increase during the time in trial in the difference in IOP between the two eyes (estimate 0.01 mm Hg, 95% CI 0.005 to 0.02, p<0.001). There were no differences between bevacizumab and ranibizumab for any of the three outcomes (p=0.93, p=0.22 and p=0.87, respectively). Conclusions Anti-vascular endothelial growth factor agents induce increases in IOP of small and uncertain clinical significance. Trial registration number ISRCTN92166560. PMID:27073205

  17. Self-Face Recognition in Schizophrenia: An Eye-Tracking Study.

    Science.gov (United States)

    Bortolon, Catherine; Capdevielle, Delphine; Salesse, Robin N; Raffard, Stéphane

    2016-01-01

    Self-face recognition has been shown to be impaired in schizophrenia (SZ), according to studies using behavioral tasks implicating cognitive demands. Here, we employed an eye-tracking methodology, which is a relevant tool to understand impairments in self-face recognition deficits in SZ because it provides a natural, continuous and online record of face processing. Moreover, it allows collecting the most relevant and informative features each individual looks at during the self-face recognition. These advantages are especially relevant considering the fundamental role played by the patterns of visual exploration on face processing. Thus, this paper aims to investigate self-face recognition deficits in SZ using eye-tracking methodology. Visual scan paths were monitored in 20 patients with SZ and 20 healthy controls. Self, famous, and unknown faces were morphed in steps of 20%. Location, number, and duration of fixations on relevant areas were recorded with an eye-tracking system. Participants performed a passive exploration task (no specific instruction was provided), followed by an active decision making task (individuals were explicitly requested to recognize the different faces). Results showed that patients with SZ had fewer and longer fixations compared to controls. Nevertheless, both groups focused their attention on relevant facial features in a similar way. No significant difference was found between groups when participants were requested to recognize the faces (active task). In conclusion, using an eye tracking methodology and two tasks with low levels of cognitive demands, our results suggest that patients with SZ are able to: (1) explore faces and focus on relevant features of the face in a similar way as controls; and (2) recognize their own face.

  18. SCORE Study Report #11: Incidences of Neovascular Events in Eyes with Retinal Vein Occlusion

    Science.gov (United States)

    Chan, Clement K.; Ip, Michael S.; VanVeldhuisen, Paul C.; Oden, Neal L.; Scott, Ingrid U.; Tolentino, Michael J.; Blodi, Barbara A.

    2010-01-01

    Purpose To investigate in The Standard Care versus COrticosteroid for REtinal Vein Occlusion (SCORE) Study: 1) incidences of neovascular events and retinal capillary nonperfusion (abbreviated as “nonperfusion”), and their relationship with treatment groups; 2) neovascular incidences by nonperfusion status; and 3) pertinent baseline factors for their potential risk for neovascular events. Design Two multi-center, randomized clinical trials: one evaluating participants with central retinal vein occlusion (CRVO) and the other evaluating participants with branch retinal vein occlusion (BRVO). Participants At 36 months, data were available for 81 participants with CRVO and 128 with BRVO. Intervention Standard care (observation or grid photocoagulation) versus 1 mg or 4 mg intravitreal triamcinolone. Main Outcome Measures Neovascularization of the iris (NVI), neovascular glaucoma (NVG), disc or retinal neovascularization (NVD/NVE), pre-retinal or vitreous hemorrhage (PRH/VH), and nonperfusion. Results Cumulative 36-month incidences for CRVO and BRVO eyes, respectively, were: 8.5% and 2.4% for NVI or NVG; 8.8 % and 7.6% for NVD/NVE or PRH/VH. There were no differences in incidences of neovascular events or risk of nonperfusion when comparing the 3 treatment groups within diseases. For CRVO at 36 months, 16.6% of eyes with ≥ 5.5 disc areas of nonperfusion vs. 4.0% of eyes with retinal capillary details caused by dense hemorrhage at baseline for CRVO eyes. Increased risk of neovascularization was noted below the historical threshold of 10 disc areas of nonperfusion for retinal vein occlusion. PMID:21440942

  19. The effect of human image in B2C website design: an eye-tracking study

    Science.gov (United States)

    Wang, Qiuzhen; Yang, Yi; Wang, Qi; Ma, Qingguo

    2014-09-01

    On B2C shopping websites, effective visual designs can bring about consumers' positive emotional experience. From this perspective, this article developed a research model to explore the impact of human image as a visual element on consumers' online shopping emotions and subsequent attitudes towards websites. This study conducted an eye-tracking experiment to collect both eye movement data and questionnaire data to test the research model. Questionnaire data analysis showed that product pictures combined with human image induced positive emotions among participants, thus promoting their attitudes towards online shopping websites. Specifically, product pictures with human image first produced higher levels of image appeal and perceived social presence, thus stimulating higher levels of enjoyment and subsequent positive attitudes towards the websites. Moreover, a moderating effect of product type was demonstrated on the relationship between the presence of human image and the level of image appeal. Specifically, human image significantly increased the level of image appeal when integrated in entertainment product pictures while this relationship was not significant in terms of utilitarian products. Eye-tracking data analysis further supported these results and provided plausible explanations. The presence of human image significantly increased the pupil size of participants regardless of product types. For entertainment products, participants paid more attention to product pictures integrated with human image whereas for utilitarian products more attention was paid to functional information of products than to product pictures no matter whether or not integrated with human image.

  20. Postural And Eye-Positional Effects On Human Biting Force: An Experimental Study

    Directory of Open Access Journals (Sweden)

    Altay Tabancacı

    2012-06-01

    Full Text Available Muscle groups affected on biting force are called temporal muscle as a major and masseter muscle as a minor. According to the human posture stability, forces of these muscles vary with the force directions. In this case, experimental investigation is strictly important such that biting force under different postural and eye- positional situations is changed. In this study, seven-male and seven-female within the age-range of 17-24 are considered corresponding to having with restorated molar tooth and without that type of tooth. With the help of specially designed biting fork, different posture- and eye-positions are investigated for experimental biting force analysis. Changes in eye-positions are not indicated significant difference for all postural positions. On one hand, it is obtained that biting force of no-filling tooth in men becomes maximum if facial muscles give full effort to biting. On the other hand, effect of facial muscles for women is not clearly noticed depending on the postural differences.

  1. Influence of aspheric intraocular lens on frequency doubling technology and contrast sensitivity: a fellow eye study

    Directory of Open Access Journals (Sweden)

    Rodrigo França de Espíndola

    2014-12-01

    Full Text Available Purpose: To evaluate whether implantation of an aspheric intraocular lens (IOL results in reduced ocular aberrations and improved contrast sensitivity after cataract surgery and, therefore, changes on frequency-doubling technology (FDT testing. Methods: The present prospective clinical study enrolled 25 patients with bilateral cataract (50 eyes, who randomly received either an aspheric (Akreos AO or a spherical (Akreos Fit IOL in one eye and the other IOL in the second eye. Assessment 12 months postoperatively included photopic and mesopic contrast sensitivity testing. Higher-order aberrations (HOAs were computed. FDT testing was divided into four areas to evaluate the variation of the values at different points. The median values of the local pattern thresholds (median area contrast sensitivity [MACS] obtained with that division were calculated. Results: The Akreos AO group obtained statistically significantly lower values of HOAs and spherical aberration compared with the Akreos Fit group. There was a statistically significant between-group difference in contrast sensitivity under mesopic conditions at all spatial frequencies. No statistically significant differences were observed in mean deviation and pattern standard deviation. The aspheric IOL exhibited higher MACS in all areas, although a statistically significant difference was reached only in the 20-degree field area (P=0.043. Conclusion: Aspheric IOLs significantly reduced spherical aberration and HOAs, improving mesopic contrast sensitivity. Although there was a trend toward slightly improved FDT in the aspheric IOL group, it was not statistically significant.

  2. Joint attention difficulties in autistic adults: An interactive eye-tracking study.

    Science.gov (United States)

    Caruana, Nathan; Stieglitz Ham, Heidi; Brock, Jon; Woolgar, Alexandra; Kloth, Nadine; Palermo, Romina; McArthur, Genevieve

    2017-04-01

    Joint attention - the ability to coordinate attention with a social partner - is critical for social communication, learning and the regulation of interpersonal relationships. Infants and young children with autism demonstrate impairments in both initiating and responding to joint attention bids in naturalistic settings. However, little is known about joint attention abilities in adults with autism. Here, we tested 17 autistic adults and 17 age- and nonverbal intelligence quotient-matched controls using an interactive eye-tracking paradigm in which participants initiated and responded to joint attention bids with an on-screen avatar. Compared to control participants, autistic adults completed fewer trials successfully. They were also slower to respond to joint attention bids in the first block of testing but performed as well as controls in the second block. There were no group differences in responding to spatial cues on a non-social task with similar attention and oculomotor demands. These experimental results were mirrored in the subjective reports given by participants, with some commenting that they initially found it challenging to communicate using eye gaze, but were able to develop strategies that allowed them to achieve joint attention. Our study indicates that for many autistic individuals, subtle difficulties using eye-gaze information persist well into adulthood.

  3. Visual social attention in autism spectrum disorder: insights from eye tracking studies.

    Science.gov (United States)

    Guillon, Quentin; Hadjikhani, Nouchine; Baduel, Sophie; Rogé, Bernadette

    2014-05-01

    We review different aspects of visual social attention in autism spectrum disorders (ASD) from infancy to adulthood in light of the eye-tracking literature. We first assess the assumption that individuals with ASD demonstrate a deficit in social orienting together with decreased attention to socially relevant stimuli such as faces compared to TD individuals. Results show that social orienting is actually not qualitatively impaired and that decreased attention to faces does not generalized across contexts. We also assess the assumption that individuals with ASD demonstrate excess mouth and diminished eye gaze compared to TD individuals. We find that this assumption receives little support across ages and discuss some factors that might have initially lead to this conjecture. We report that the assessment of the ability to follow the direction of another person's gaze needs to be further examined and that eye-tracking studies add to the evidence that individuals with ASD demonstrate difficulties in interpreting gaze cues. Finally, we highlight innovative data acquisition and analyses that are increasingly shedding light on the more subtle nature of the profound social difficulties experienced by individuals with ASD.

  4. Eye movements as an index of pathologist visual expertise: a pilot study.

    Directory of Open Access Journals (Sweden)

    Tad T Brunyé

    Full Text Available A pilot study examined the extent to which eye movements occurring during interpretation of digitized breast biopsy whole slide images (WSI can distinguish novice interpreters from experts, informing assessments of competency progression during training and across the physician-learning continuum. A pathologist with fellowship training in breast pathology interpreted digital WSI of breast tissue and marked the region of highest diagnostic relevance (dROI. These same images were then evaluated using computer vision techniques to identify visually salient regions of interest (vROI without diagnostic relevance. A non-invasive eye tracking system recorded pathologists' (N = 7 visual behavior during image interpretation, and we measured differential viewing of vROIs versus dROIs according to their level of expertise. Pathologists with relatively low expertise in interpreting breast pathology were more likely to fixate on, and subsequently return to, diagnostically irrelevant vROIs relative to experts. Repeatedly fixating on the distracting vROI showed limited value in predicting diagnostic failure. These preliminary results suggest that eye movements occurring during digital slide interpretation can characterize expertise development by demonstrating differential attraction to diagnostically relevant versus visually distracting image regions. These results carry both theoretical implications and potential for monitoring and evaluating student progress and providing automated feedback and scanning guidance in educational settings.

  5. Eye Movement Training and Suggested Gaze Strategies in Tunnel Vision - A Randomized and Controlled Pilot Study.

    Directory of Open Access Journals (Sweden)

    Iliya V Ivanov

    Full Text Available Degenerative retinal diseases, especially retinitis pigmentosa (RP, lead to severe peripheral visual field loss (tunnel vision, which impairs mobility. The lack of peripheral information leads to fewer horizontal eye movements and, thus, diminished scanning in RP patients in a natural environment walking task. This randomized controlled study aimed to improve mobility and the dynamic visual field by applying a compensatory Exploratory Saccadic Training (EST.Oculomotor responses during walking and avoiding obstacles in a controlled environment were studied before and after saccade or reading training in 25 RP patients. Eye movements were recorded using a mobile infrared eye tracker (Tobii glasses that measured a range of spatial and temporal variables. Patients were randomly assigned to two training conditions: Saccade (experimental and reading (control training. All subjects who first performed reading training underwent experimental training later (waiting list control group. To assess the effect of training on subjects, we measured performance in the training task and the following outcome variables related to daily life: Response Time (RT during exploratory saccade training, Percent Preferred Walking Speed (PPWS, the number of collisions with obstacles, eye position variability, fixation duration, and the total number of fixations including the ones in the subjects' blind area of the visual field.In the saccade training group, RTs on average decreased, while the PPWS significantly increased. The improvement persisted, as tested 6 weeks after the end of the training. On average, the eye movement range of RP patients before and after training was similar to that of healthy observers. In both, the experimental and reading training groups, we found many fixations outside the subjects' seeing visual field before and after training. The average fixation duration was significantly shorter after the training, but only in the experimental training

  6. Association of open-angle glaucoma loci with incident glaucoma in the Blue Mountains Eye Study.

    Science.gov (United States)

    Burdon, Kathryn P; Mitchell, Paul; Lee, Anne; Healey, Paul R; White, Andrew J R; Rochtchina, Elena; Thomas, Peter B M; Wang, Jie Jin; Craig, Jamie E

    2015-01-01

    To determine if open-angle glaucoma (OAG)-associated single nucleotide polymorphisms (SNPs) are associated with incident glaucoma and if such genetic information is useful in OAG risk prediction. Case-control from within a population-based longitudinal study. study population: Individuals aged over 49 years of age living in the Blue Mountains region west of Sydney and enrolled in the Blue Mountains Eye Study. observation: Cases for this sub-study (n = 67) developed incident OAG between baseline and 10-year visits, in either eye, while controls (n = 1919) had no evidence for OAG at any visit. All participants had an ocular examination and DNA genotyped for reported OAG risk SNPs. main outcome measure: Incident OAG. Two loci also known to be associated with cup-to-disc ratio as well as OAG (9p21 near CDKN2B-AS1 and SIX1/SIX6) were both significantly associated with incident OAG in the Blue Mountains Eye Study cohort (P = .006 and P = .004, respectively). The TMCO1 locus was nominally associated (P = .012), while the CAV1/CAV2 and 8q22 loci were not associated. Multivariate logistic regression and neural network analysis both indicated that the genetic risk factors contributed positively to the predictive models incorporating traditional risk factors. This study shows that previously reported genetic variations related to OAG and cup-to-disc ratio are associated with the onset of OAG and thus may become useful in risk prediction algorithms designed to target early treatment to those most at risk of developing glaucoma. Copyright © 2015 The Authors. Published by Elsevier Inc. All rights reserved.

  7. The Source Of Dust Jets Seen In Comet 103p/hartley 2.

    Science.gov (United States)

    Belton, Michael J. S.

    2012-10-01

    Comet 103P/Hartley 2 displays at least three different types of jet phenomena: highly structured CO2 driven jets seen in EPOXI encounter images (A’Hearn et al 2011), large scale jet phenomena that show in CN emission (e.g. Knight and Schleicher, 2012), and fainter dust jet or “cloud” structures seen in ground-based images (Lara et al., (2011), Mueller et al., (2012), Tozzi et al., 2012, Knight and Schleicher, 2012). The dust jets are observed to change their projected orientations slowly from night-to-night, and even during a night. From this behavior Knight and Schleicher (2012) have suggested that the source of the jets might be located near the comet’s total angular momentum vector and that they might be driven by CO, or more likely, CO2. In this paper we investigate the source of the dust jets using the shape modelof the comet’s nucleus (Thomas et al 2012) and a model of the comet’s complex spin state (Belton et al 2012) based on EPOXI observations. We show that the reason why the dust jet changes its projected direction is most likely the changing orientation of the surface at the sub-solar region during the spin cycle. In this scenario the jet source is not tied to the surface and is most likely driven by H2O sublimation. A’Hearn et al. 2011. Science 332, 1396-1400. Lara et al. 2011, A&A 532, A87 Mueller et al. 2012, AAS meeting 220, Abstract #120.03 Tozzi et al. 2012, preprint, submitted to Icarus Knight & Schleicher, 2012, Icarus, accepted for publication Thomas et al. 2012, Icarus, accepted for publication Belton et al. 2012, Icarus, accepted for publication

  8. Ground-based multiwavelength observations of comet 103P/Hartley 2

    Energy Technology Data Exchange (ETDEWEB)

    Gicquel, A.; Villanueva, G. L.; Cordiner, M. A. [Catholic University of America, Physics Department, 620 Michigan Avenue NE, Washington, DC (United States); Milam, S. N.; Charnley, S. B. [Goddard Center for Astrobiology, NASA Goddard Space Flight Center, 8800 Greenbelt Road, Greenbelt, MD 20771 (United States); Remijan, A. J. [National Radio Astronomy Observatory, 520 Edgemont Road, Charlottesville, VA 22903 (United States); Coulson, I. M. [Joint Astronomy Centre, 660 North A' ohoku Place University Park, Hilo, HI 96720 (United States); Chuang, Y.-L.; Kuan, Y.-J., E-mail: adeline.gicquel@nasa.gov, E-mail: stefanie.n.milam@nasa.gov, E-mail: geronimo.l.villanueva@nasa.gov, E-mail: steven.b.charnley@nasa.gov, E-mail: martin.a.cordiner@nasa.gov, E-mail: aremijan@nrao.edu, E-mail: i.coulson@jach.hawaii.edu, E-mail: ylchuang@std.ntnu.edu.tz, E-mail: kuan@ntnu.edu.tw [National Taiwan Normal University, 88 Sec. 4 Ting-Chou Road, Taipei 116, Taiwan (China)

    2014-10-10

    The Jupiter-family comet 103P/Hartley 2 (103P) was the target of the NASA EPOXI mission. In support of this mission, we conducted observations from radio to submillimeter wavelengths of comet 103P in the three weeks preceding the spacecraft rendezvous on UT 2010 November 4.58. This time period included the passage at perihelion and the closest approach of the comet to the Earth. Here, we report detections of HCN, H{sub 2}CO, CS, and OH and upper limits for HNC and DCN toward 103P using the Arizona Radio Observatory Kitt Peak 12 m telescope (ARO 12 m) and submillimeter telescope (SMT), the James Clerk Maxwell Telescope (JCMT), and the Green Bank Telescope (GBT). The water production rate, Q{sub H{sub 2O}} = (0.67-1.07) × 10{sup 28} s{sup –1}, was determined from the GBT OH data. From the average abundance ratios of HCN and H{sub 2}CO relative to water (0.13 ± 0.03% and 0.14 ± 0.03%, respectively), we conclude that H{sub 2}CO is depleted and HCN is normal with respect to typically observed cometary mixing ratios. However, the abundance ratio of HCN with water shows a large diversity with time. Using the JCMT data, we measured an upper limit for the DCN/HCN ratio <0.01. Consecutive observations of ortho-H{sub 2}CO and para-H{sub 2}CO on November 2 (from data obtained at the JCMT) allowed us to derive an ortho:para ratio (OPR) of ≈2.12 ± 0.59 (1σ), corresponding to T {sub spin} > 8 K (2σ).

  9. Relationship between retinal vessel diameters and retinopathy in the Inter99 Eye Study

    DEFF Research Database (Denmark)

    Drobnjak, Dragana; Munch, Inger Christine; Glümer, Charlotte

    2017-01-01

    .001), and decreased with higher HDL cholesterol (p  diabetes, but not in participants without diabetes......© 2017 The Authors Purpose To examine the association between retinal vessel diameters and retinopathy in participants with and without type 2 diabetes in a Danish population-based cohort. Methods The study included 878 persons aged 30 to 60 years from the Inter99 Eye Study. Retinopathy was defined...... as a presence of one or more retinal hemorrhages or one or more microaneurysms. Vessel diameters were expressed as central retinal artery equivalent diameter (CRAE) and central retinal vein equivalent diameter (CRVE). Multiple linear regression analyses were performed. Results Among participants with diabetes...

  10. A clinical study of the efficacy of topical corticosteroids on dry eye

    Institute of Scientific and Technical Information of China (English)

    YANG Chong-qing; SUN Wen; GU Yang-shun

    2006-01-01

    Objective: To evaluate the effect of topical corticosteroid for treatment of moderate or severe dry eye. Methods: Sixty eyes of 30 patients with moderate or severe dry eye, who were not sensitive to artificial tears, were treated with 0.1% fluorometholone eye drops. Subjective symptom and objective tests were used to evaluate the efficacy of treatment before and after application of 0.1% fluorometholone eye drops for 1 week and 1 month. Side effects were also evaluated. Results: After 1 week of treatment, subjective symptoms were improved in all dry eye patients; objective tests were improved in all dry eye patients 1month after treatment, and the difference was significant. Conclusion: Topical corticosteroid drops can rapidly and effectively relieve the symptoms and signs of moderate or severe dry eye.

  11. Prevalence of Cataract Surgery and Visual Outcomes in Indian Immigrants in Singapore: The Singapore Indian Eye Study

    OpenAIRE

    Preeti Gupta; Yingfeng Zheng; Tay Wan Ting; Ecosse L Lamoureux; Ching-Yu Cheng; Tien-Yin Wong

    2013-01-01

    OBJECTIVE: To determine the prevalence of cataract surgery and factors associated with post-surgical visual outcomes in migrant Indians living in Singapore. RESEARCH DESIGN AND METHODS: We conducted a population-based study in 3,400 Indian immigrants residing in Singapore-the Singapore Indian Eye Study (SINDI). All participants underwent comprehensive medical eye examination and a standardized interview. Post-operative visual impairment (VI) was defined as best-corrected or presenting visual ...

  12. Temporal and Spatial Aspects of Gas Release During the 2010 Apparition of Comet 103P/Hartley-2

    OpenAIRE

    Mumma, M. J.; Bonev, B. P.; Villanueva, G. L.; Paganini, L.; DiSanti, M. A.; Gibb, E. L.; Keane, J. V.; Meech, K. J.; Blake, G. A.; Ellis, R. S.; Lippi, M.; Bõhnhardt, H.; Magee-Sauer, K.

    2011-01-01

    We report measurements of eight primary volatiles (H_(2)O, HCN, CH_4, C_(2)H_6, CH_(3)OH, C_(2)H_2, H_(2)CO, and NH_3) and two product species (OH and NH_2) in comet 103P/Hartley 2 using high-dispersion infrared spectroscopy. We quantified the long- and short-term behavior of volatile release over a three-month interval that encompassed the comet's close approach to Earth, its perihelion passage, and flyby of the comet by the Deep Impact spacecraft during the EPOXI mission. We present product...

  13. Cataract Surgery and Visual Acuity in Elderly Japanese: Results of Fujiwara-kyo Eye Study

    Science.gov (United States)

    Miyata, Kimie; Yoshikawa, Tadanobu; Mine, Masashi; Nishi, Tomo; Okamoto, Nozomi; Ueda, Tetsuo; Kawasaki, Ryo; Kurumatani, Norio; Ogata, Nahoko

    2017-01-01

    Abstract The aim of this study was to determine the presence of prior cataract surgery and best-corrected visual acuity (BCVA) in an elderly Japanese cohort. The Fujiwara-kyo Eye Study was a prospective, population-based, cross-sectional epidemiological study. The subjects were ≥68 years who lived in the Nara Prefecture and responded to recruitment notices. All of the subjects underwent comprehensive ophthalmological examinations, and the sociodemographic information and medical history, including prior cataract surgery, were obtained by answers to a questionnaire. The associations between the BCVA, age, sex, and history of cataract surgery were determined. A total of 2,873 subjects whose mean age was 76.3 ± 4.9 (mean ± standard deviation) years were studied. The mean BCVA was −0.020 ± 0.14 logarithm of the minimum angle of resolution units, and it was significantly better in the group with education ≥13 years (p < 0.01). Overall, 24.2% of the subjects had undergone cataract surgery, and 41.7% of the subjects ≥80 years had undergone cataract surgery. The incidence of prior cataract surgery increased with increasing age (p < 0.001 for trend). The mean BCVA of eyes with cataract surgery was significantly better than that of eyes without cataract surgery in subjects ≥80 years (p < 0.01). Visual acuity was generally good in this cohort of elderly Japanese subjects. In this cohort, 24.2% of the subjects had undergone cataract surgery, and the subjects ≥80 years had better BCVA than those without cataract surgery. PMID:28451472

  14. Loneliness and hypervigilance to social cues in females: an eye-tracking study.

    Directory of Open Access Journals (Sweden)

    Gerine M A Lodder

    Full Text Available The goal of the present study was to examine whether lonely individuals differ from nonlonely individuals in their overt visual attention to social cues. Previous studies showed that loneliness was related to biased post-attentive processing of social cues (e.g., negative interpretation bias, but research on whether lonely and nonlonely individuals also show differences in an earlier information processing stage (gazing behavior is very limited. A sample of 25 lonely and 25 nonlonely students took part in an eye-tracking study consisting of four tasks. We measured gazing (duration, number of fixations and first fixation at the eyes, nose and mouth region of faces expressing emotions (Task 1, at emotion quadrants (anger, fear, happiness and neutral expression (Task 2, at quadrants with positive and negative social and nonsocial images (Task 3, and at the facial area of actors in video clips with positive and negative content (Task 4. In general, participants tended to gaze most often and longest at areas that conveyed most social information, such as the eye region of the face (T1, and social images (T3. Participants gazed most often and longest at happy faces (T2 in still images, and more often and longer at the facial area in negative than in positive video clips (T4. No differences occurred between lonely and nonlonely participants in their gazing times and frequencies, nor at first fixations at social cues in the four different tasks. Based on this study, we found no evidence that overt visual attention to social cues differs between lonely and nonlonely individuals. This implies that biases in social information processing of lonely individuals may be limited to other phases of social information processing. Alternatively, biased overt attention to social cues may only occur under specific conditions, for specific stimuli or for specific lonely individuals.

  15. Loneliness and Hypervigilance to Social Cues in Females: An Eye-Tracking Study

    Science.gov (United States)

    Lodder, Gerine M. A.; Scholte, Ron H. J.; Clemens, Ivar A. H.; Engels, Rutger C. M. E.; Goossens, Luc; Verhagen, Maaike

    2015-01-01

    The goal of the present study was to examine whether lonely individuals differ from nonlonely individuals in their overt visual attention to social cues. Previous studies showed that loneliness was related to biased post-attentive processing of social cues (e.g., negative interpretation bias), but research on whether lonely and nonlonely individuals also show differences in an earlier information processing stage (gazing behavior) is very limited. A sample of 25 lonely and 25 nonlonely students took part in an eye-tracking study consisting of four tasks. We measured gazing (duration, number of fixations and first fixation) at the eyes, nose and mouth region of faces expressing emotions (Task 1), at emotion quadrants (anger, fear, happiness and neutral expression) (Task 2), at quadrants with positive and negative social and nonsocial images (Task 3), and at the facial area of actors in video clips with positive and negative content (Task 4). In general, participants tended to gaze most often and longest at areas that conveyed most social information, such as the eye region of the face (T1), and social images (T3). Participants gazed most often and longest at happy faces (T2) in still images, and more often and longer at the facial area in negative than in positive video clips (T4). No differences occurred between lonely and nonlonely participants in their gazing times and frequencies, nor at first fixations at social cues in the four different tasks. Based on this study, we found no evidence that overt visual attention to social cues differs between lonely and nonlonely individuals. This implies that biases in social information processing of lonely individuals may be limited to other phases of social information processing. Alternatively, biased overt attention to social cues may only occur under specific conditions, for specific stimuli or for specific lonely individuals. PMID:25915656

  16. Influence of Eye Gaze on Spoken Word Processing: An ERP Study with Infants

    Science.gov (United States)

    Parise, Eugenio; Handl, Andrea; Palumbo, Letizia; Friederici, Angela D.

    2011-01-01

    Eye gaze is an important communicative signal, both as mutual eye contact and as referential gaze to objects. To examine whether attention to speech versus nonspeech stimuli in 4- to 5-month-olds (n = 15) varies as a function of eye gaze, event-related brain potentials were used. Faces with mutual or averted gaze were presented in combination with…

  17. A Review on Eye Movement Studies in Childhood and Adolescent Psychiatry

    Science.gov (United States)

    Rommelse, Nanda N. J.; Van der Stigchel, Stefan; Sergeant, Joseph A.

    2008-01-01

    The neural substrates of eye movement measures are largely known. Therefore, measurement of eye movements in psychiatric disorders may provide insight into the underlying neuropathology of these disorders. Visually guided saccades, antisaccades, memory guided saccades, and smooth pursuit eye movements will be reviewed in various childhood…

  18. A Review on Eye Movement Studies in Childhood and Adolescent Psychiatry

    Science.gov (United States)

    Rommelse, Nanda N. J.; Van der Stigchel, Stefan; Sergeant, Joseph A.

    2008-01-01

    The neural substrates of eye movement measures are largely known. Therefore, measurement of eye movements in psychiatric disorders may provide insight into the underlying neuropathology of these disorders. Visually guided saccades, antisaccades, memory guided saccades, and smooth pursuit eye movements will be reviewed in various childhood…

  19. A PROSPECTIVE OBSERVATIONAL STUDY REGARDING PREVALENCE OF DRY EYE DISEASE IN POST-OPERATIVE CATARACT SURGERY PATIENTS OF 140 CASES.

    Directory of Open Access Journals (Sweden)

    S. Srinivasan

    2017-02-01

    Full Text Available BACKGROUND Dry eye disease is one of the most common ocular surface disorder with large number of studies carried out in various countries estimate the prevalence of dry eye disease to be between 5-34%. The prevalence of dry eye increases with age. As per Breaver Dam study regarding dry eye the prevalence of DED 13.3%. Dry eye was apparently higher in women than men. Studies have shown that cataract surgery worsen dry eye symptoms in patients with preexisting dry eye symptoms as well as without preexisting DES, mostly dry eye symptoms last for two months of post cataract surgery period. MATERIALS AND METHODS The prospective observational study was conducted in Department of Ophthalmology, Government Vellore Medical College and Hospital, Vellore. The total number of cataract surgery performed cases were 140 in number. The study period was four months, conducted in tertiary eye center. The Cataract patients were preoperatively at normal tear secretions. Post cataract surgery period from first POD, one week POD, four weeks, six weeks, two months and three months POD examined by slit lamp, Schirmer's test I, TBUT and corneal sensitivity test were performed. RESULTS Our study revealed that increased prevalence in female sex with increased age group range from 51-70 years showed post cataract surgery period dryness of eye. The ratio of Post cataract surgery DED in male and female is 13:29. This shows increased female sex prevalence of postoperative DED. In our study, the prevalence of post cataract surgery dry eye disease was 30%. CONCLUSION 73% cataract surgeries is now clear corneal cataract surgery and this procedure cuts a large part of corneal nerves. The nerve essential for tear production gets disturbed leading to dryness and hence decreased visual function. The corneal nerves are important in self-regulation of tears since they provide the sensation in the feedback loop that signals tear production. When the functions of the nerves get blocked

  20. Association of Visual Acuity and Cognitive Impairment in Older Individuals: Fujiwara-kyo Eye Study

    Science.gov (United States)

    Mine, Masashi; Miyata, Kimie; Morikawa, Masayuki; Nishi, Tomo; Okamoto, Nozomi; Kawasaki, Ryo; Yamashita, Hidetoshi; Kurumatani, Norio; Ogata, Nahoko

    2016-01-01

    Abstract Both visual impairment and cognitive impairment are essential factors that determine the quality of life in the aged population. The aim of this study was to determine if a correlation existed between visual acuity and cognitive impairment in an elderly Japanese population. The Fujiwara-kyo Eye Study was a cross-sectional study of individuals aged ≥68 years who lived in Nara Prefecture of Japan. Participants underwent ophthalmological examinations and cognitive function test. A mild visual impairment was defined as having a best corrected visual acuity (BCVA) >0.2 logarithm of the minimum angle of resolution (logMAR) units in the better eye. Cognitive impairment was defined as having a Mini-Mental State Examination (MMSE) score of ≤23 points. A total to 2818 individuals completed the examinations. The mean age of the participants was 76.3 ± 4.8 years (mean ± standard deviation). The mean BCVA of the better eye was −0.02 ± 0.13 logMAR units and 6.6% subjects were classified as being mildly visually impaired. The mean MMSE score was 27.3 ± 2.3 and 5.7% subjects were classified as being cognitively impaired. The proportion of subjects with cognitive or moderate visual impairment increased with age, and there was a significant correlation between the visual acuity and MMSE score (r = −0.10, p < 0.0001). Subjects with mild visual impairments had 2.4 times higher odds of having cognitive impairment than those without visual impairment (odds ratio 2.4, 95% confidence interval, 1.5–3.8, p < 0.001) after adjusting for age, sex, and length of education. We conclude that it may be important to maintain good visual acuity to reduce the risk of having cognitive impairment. PMID:27610269

  1. Cyclosporine A Loaded PLGA Nanoparticles for Dry Eye Disease: In Vitro Characterization Studies

    Directory of Open Access Journals (Sweden)

    Vijay D. Wagh

    2014-01-01

    Full Text Available Dry eye disease is a common disease of the tear film caused by decreased tear production or increased evaporation. The objective of this study was to develop and evaluate poly (dl-lactide-co-glycolide (PLGA nanoparticles for CsA (CsA ophthalmic delivery, for the treatment of dry eye disease. Topical CsA is currently the only and safe pharmacologic treatment of severe dry eye symptoms. Nanoparticles (NPs were prepared by W/O solvent evaporation technique followed by probe sonicator and characterized for various properties such as particle size, entrapment efficiency, zeta potential, in vitro drug release, in vitro permeation studies by Franz diffusion cells, XRD, DSC, SEM, and stability studies. The developed nanosuspension showed a mean particle size in the range from 128 to 253.50 nm before freeze drying and after freeze drying 145.60 to 260.0 nm. The drug entrapment efficiency was from 58.35 to 95.69% and production yield was found between 52.29±2.4 and 85.30±2.1% in all preparations. The zeta potential of the Eudragit RL containing nanoparticles was positive, that is, 20.3 mV to 34.5 mV. The NPs formulations exhibited a biphasic drug release with initial burst followed by a very slow drug release and total cumulative release up to 24 h ranged from 69.83 to 91.92%. Kinetically, the release profiles of CsA from NPs appeared to fit best with the Higuchi model. The change of surface characteristics of NPs represents a useful approach for improvement of ocular retention and drug availability.

  2. Association of Visual Acuity and Cognitive Impairment in Older Individuals: Fujiwara-kyo Eye Study.

    Science.gov (United States)

    Mine, Masashi; Miyata, Kimie; Morikawa, Masayuki; Nishi, Tomo; Okamoto, Nozomi; Kawasaki, Ryo; Yamashita, Hidetoshi; Kurumatani, Norio; Ogata, Nahoko

    2016-01-01

    Both visual impairment and cognitive impairment are essential factors that determine the quality of life in the aged population. The aim of this study was to determine if a correlation existed between visual acuity and cognitive impairment in an elderly Japanese population. The Fujiwara-kyo Eye Study was a cross-sectional study of individuals aged ≥68 years who lived in Nara Prefecture of Japan. Participants underwent ophthalmological examinations and cognitive function test. A mild visual impairment was defined as having a best corrected visual acuity (BCVA) >0.2 logarithm of the minimum angle of resolution (logMAR) units in the better eye. Cognitive impairment was defined as having a Mini-Mental State Examination (MMSE) score of ≤23 points. A total to 2818 individuals completed the examinations. The mean age of the participants was 76.3 ± 4.8 years (mean ± standard deviation). The mean BCVA of the better eye was -0.02 ± 0.13 logMAR units and 6.6% subjects were classified as being mildly visually impaired. The mean MMSE score was 27.3 ± 2.3 and 5.7% subjects were classified as being cognitively impaired. The proportion of subjects with cognitive or moderate visual impairment increased with age, and there was a significant correlation between the visual acuity and MMSE score (r = -0.10, p < 0.0001). Subjects with mild visual impairments had 2.4 times higher odds of having cognitive impairment than those without visual impairment (odds ratio 2.4, 95% confidence interval, 1.5-3.8, p < 0.001) after adjusting for age, sex, and length of education. We conclude that it may be important to maintain good visual acuity to reduce the risk of having cognitive impairment.

  3. Peripheral Retinal Changes Associated with Age-Related Macular Degeneration in the Age-Related Eye Disease Study 2: Age-Related Eye Disease Study 2 Report Number 12 by the Age-Related Eye Disease Study 2 Optos PEripheral RetinA (OPERA) Study Research Group.

    Science.gov (United States)

    Domalpally, Amitha; Clemons, Traci E; Danis, Ronald P; Sadda, SriniVas R; Cukras, Catherine A; Toth, Cynthia A; Friberg, Thomas R; Chew, Emily Y

    2017-04-01

    To compare rates of peripheral retinal changes in Age-Related Eye Disease Study 2 (AREDS2) participants with at least intermediate age-related macular degeneration (AMD) with control subjects without intermediate age-related changes (large drusen). Cross-sectional evaluation of clinic-based patients enrolled in AREDS2 and a prospective study. Participants from prospective studies. The 200° pseudocolor and fundus autofluorescence (FAF) images were captured on the Optos 200 Tx Ultrawide-field device (Optos, Dunfermline, Scotland) by centering on the fovea and then steering superiorly and inferiorly. The montaged images were graded at a reading center with the images divided into 3 zones (zone 1 [posterior pole], zone 2 [midperiphery], and zone 3 [far periphery]) to document the presence of peripheral lesions. Peripheral retinal lesions: drusen, hypopigmentary/hyperpigmentary changes, reticular pseudodrusen, senile reticular pigmentary changes, cobblestone degeneration, and FAF abnormalities. A total of 484 (951 eyes) AREDS2 participants with AMD (cases) and 89 (163 eyes) controls without AMD had gradable color and FAF images. In zones 2 and 3, neovascularization and geographic atrophy (GA) were present, ranging from 0.4% to 6% in eyes of cases, respectively, and GA was present in 1% of eyes of controls. Drusen were detected in 97%, 78%, and 64% of eyes of cases and 48%, 21%, and 9% of eyes of controls in zones 2 and 3 superior and 3 inferior, respectively (P < 0.001 for all). Peripheral reticular pseudodrusen were seen in 15%. Senile reticular pigmentary change was the predominant peripheral change seen in 48% of cases and 16% of controls in zone 2 (P < 0.001). Nonreticular pigment changes were less frequent in the periphery than in the posterior pole (46% vs. 76%) and negligible in controls. Peripheral retinal changes are more prevalent in eyes with AMD than in control eyes. Drusen are seen in a majority of eyes with AMD in both the mid and far periphery, whereas

  4. Using an eye tracker during medication administration to identify gaps in nursing students' contextual knowledge: an observational study.

    Science.gov (United States)

    Amster, Brian; Marquard, Jenna; Henneman, Elizabeth; Fisher, Donald

    2015-01-01

    In this clinical simulation study using an eye-tracking device, 40% of senior nursing students administered a contraindicated medication to a patient. Our findings suggest that the participants who did not identify the error did not know that amoxicillin is a type of penicillin. Eye-tracking devices may be valuable for determining whether nursing students are making rule- or knowledge-based errors, a distinction not easily captured via observations and interviews.

  5. The pupil is faster than the corneal reflection (CR): are video based pupil-CR eye trackers suitable for studying detailed dynamics of eye movements?

    NARCIS (Netherlands)

    Hooge, I.T.C.; Holmqvist, K.; Nyström, Marcus

    2016-01-01

    Most modern video eye trackers use the p-CR (pupil minus CR) technique to deal with small relative movements between the eye tracker camera and the eye. We question whether the p-CR technique is appropriate to investigate saccade dynamics. In two experiments we investigated the dynamics of pupil, CR

  6. Clinical features of diabetic patients with dry eye disease in a community in Maceio: a cross-sectional study

    Directory of Open Access Journals (Sweden)

    Marina Viegas Moura Rezende Ribeiro

    2016-04-01

    Full Text Available ABSTRACT Objective: This study was carried out in order to assess the epidemiological profile of symptomatic dry eye in diabetic patients. Methods: Two hundred and twenty-one diabetic patients were evaluated using a specific questionnaire about other diseases and drugs. Of these, 58 who classified as having moderate to severe dry eye were included. Results: In this study, 58 of the 221 diabetic patients had moderate to severe dry eye (26.2%. Of the 58 patients, dry eye was more prevalent at age 61.46 ± 14.18 years for men, and 61.09 ± 10.64 for women (p<0.005. Dry eye was more common in women (75.9% (p=0.456. Of the 58 patients, 15 (25.9% had at least one ocular disease.The most common was diabetic retinopathy (13 of 15 patients, 86.7%, 95% CI 69.46-103.87. A total of 19 patients used eye drops (32.8%; and most (14 of the 19 individuals, 73.7% used lubricants (95%CI 53.88-93.48. Hypertension was the most prevalent associated comorbidity (56.9% and the most commonly used medications were hypoglycemic agents (98 %, 95%CI 94.00 - 101.92 and angiotensin converting enzyme inhibitors (53.1%, 95%CI 53.06 39.09 - 67.04. Conclusion: Further epidemiologic studies need to be done to establish a real etiologic relationship between diabetes and dry eye, and its correlation to other risk factors. In spite of these limitations, we have strong evidence of this relationship, and in clinical practice, examination for dry eye should be part of the assessment of diabetic disease.

  7. TU-E-201-01: Methods for Eye Lens Dosimetry and Studies On Lens Opacities with Interventionists

    Energy Technology Data Exchange (ETDEWEB)

    Rehani, M. [Massachusetts General Hospital (United States)

    2015-06-15

    Madan M. Rehani, Massachusetts General Hospital and Harvard Medical School, Boston Methods for Eye Lens Dosimetry and Studies On Lens Opacities with Interventionalists Radiation induced cataract is a major threat among staff working in interventional suites. Nearly 16 million interventional procedures are performed annually in USA. Recent studies by the principal investigator’s group, primarily among interventional cardiologists, on behalf of the International Atomic Energy Agency, show posterior subcapsular (PSC) changes in the eye lens in 38–53% of main operators and 21–45% of support staff. These changes have potential to lead to cataract in future years, as per information from A-Bomb survivors. The International Commission on Radiological Protection has reduced dose limit for staff by a factor of 7.5 (from 150 mSv/y to 20 mSv/y). With increasing emphasis on radiation induced cataracts and reduction in threshold dose for eye lens, there is a need to implement strategies for estimating eye lens dose. Unfortunately eye lens dosimetry is at infancy when it comes to routine application. Various approaches are being tried namely direct measurement using active or passive dosimeters kept close to eyes, retrospective estimations and lastly correlating patient dose in interventional procedures with staff eye dose. The talk will review all approaches available and ongoing active research in this area, as well as data from surveys done in Europe on status of eye dose monitoring in interventional radiology and nuclear medicine. The talk will provide update on how good is Hp(10) against Hp(3), estimations from CTDI values, Monte Carlo based simulations and current status of eye lens dosimetry in USA and Europe. The cataract risk among patients is in CT examinations of the head. Since radiation induced cataract predominantly occurs in posterior sub-capsular (PSC) region and is thus distinguishable from age or drug related cataracts and is also preventable, actions on

  8. Transgenic studies on the role of optineurin in the mouse eye.

    Science.gov (United States)

    Kroeber, Markus; Ohlmann, Andreas; Russell, Paul; Tamm, Ernst R

    2006-06-01

    Mutations in the OPTN gene encoding for optineurin have been associated with primary open-angle glaucoma. The functional role(s) of optineurin in the normal and glaucomatous eye are unclear. As optineurin interferes with TNF-alpha mediated cell death in vitro, an involvement of optineurin in the regulatory pathways leading to apoptosis of retinal ganglion cells has been suggested. The goal of the present study was to study the molecular properties of optineurin and its capabilities to prevent apoptosis in vivo in the eyes of transgenic mice. The chicken betaB1-crystallin promoter was used to overexpress ectopic optineurin in the lenses of transgenic mice. The expression of transgenic mRNA was monitored by northern blot analysis. The localization of transgenic optineurin was investigated by one- and two-dimensional western blot analysis and by immunohistochemistry, and compared with that of endogenous optineurin. To assess effects of transgenic optineurin on apoptosis, betaB1-crystallin-OPTN mice were crossbred with betaB1-crystallin-TGFbeta1 mice that undergo substantial TGF-beta1-induced apoptotic cell death in the lens. Two independent betaB1-crystallin-OPTN transgenic lines were established, in which transgenic optineurin was expressed strictly lens-specific as assessed by Northern and Western blotting, and by immunohistochemistry. In contrast, endogenous optineurin was preferentially expressed in the retina, where retinal ganglion cells showed strong labeling. Immunostaining for endogenous optineurin in the anterior eye was considerably weaker than in the posterior eye and was seen in iris, ciliary epithelium, cells of corneal stroma and endothelium, and in the trabecular meshwork. Neither transgenic nor endogenous optineurin was found in the aqueous humor. Transgenic overexpression of optineurin did not have measurable effects on TGFbeta1-induced apoptosis in mixed betaB1-crystallin-OPTN/betaB1-crystallin-TGFbeta1 transgenic mice. Our results show that

  9. Danish Rural Eye Study: the association of preschool vision screening with the prevalence of amblyopia.

    Science.gov (United States)

    Høeg, Tracy B; Moldow, Birgitte; Ellervik, Christina; Klemp, Kristian; Erngaard, Ditte; la Cour, Morten; Buch, Helena

    2015-06-01

    To determine the prevalence of amblyopia in Denmark before and after the initiation of the Danish national preschool vision screening programme. In a population-based cross-sectional study, 3826 participants of the Danish General Suburban Population Study (GESUS) aged 20 years and older from a Danish rural municipality received a complete general health examination and an ophthalmological interview and examination. This study included a comprehensive ophthalmologic interview, measurement of best corrected visual acuity (BCVA) in each eye, Hirschberg's test for strabismus and two 45-degree retinal fundus photographs of each eye. A complete ophthalmologic examination was performed when indicated. The prevalence of monocular visual impairment (MVI) was 4.26% (95% CI, 3.66-4.95, n = 163). Amblyopia was the most common cause, accounting for 33%. The prevalence of amblyopia was 1.44% (95% CI, 1.01-1.81, n = 55), being higher among non-preschool vision screened persons compared to those who were offered (estimated 95% attendance) preschool vision screening (1.78%, n = 41, 95% CI 1.24-2.33 versus 0.44%, n = 2, 95% CI, 0.12-1.60, p = 0.024). The leading cause of amblyopia was anisometropia (45.5%, 25/55). Amblyopia was the most common cause of MVI. Following the initiation of the Danish national preschool vision screening programme, which has an approximate attendance rate of 95%, the prevalence of amblyopia decreased by fourfold. © 2014 Acta Ophthalmologica Scandinavica Foundation. Published by John Wiley & Sons Ltd.

  10. A preliminary study of the neuroprotective role of citicoline eye drops in glaucomatous optic neuropathy.

    Science.gov (United States)

    Roberti, Gloria; Tanga, Lucia; Parisi, Vincenzo; Sampalmieri, Massimo; Centofanti, Marco; Manni, Gianluca

    2014-05-01

    To study the neuroprotective effect of topical citicoline. Experimental phase to evaluate the ability of citicoline eye drops to reach the vitreous and the retina: The right eyes of 5 mice CD1 were treated with two drops per day for three days of citicoline 1% and 2% (OMK1, Omikron Italia s.r.l.), and then the vitreous was analyzed with the liquid chromatography and spectrometry mass (LC-MS/MS). Clinical phase to determine if topical citicoline is able to delay glaucoma progression, considering perimetric parameters and electro functional tests. Patients were randomized in two groups, OMK1 and OAG. The first group was treated with OMK1 three times per day, plus hypotensive therapy for two months and one month of wash out. The second group was treated only with hypotensive treatment for three months. LC-MS/MS detected the molecule very well, and only OMK1 showed systemic absorption. Thirty-four patients were enrolled, 16 in the OMK1 and 18 in the OAG group. Perimetric parameters showed a positive trend in individual eyes of patients in OMK1 group, but these values were not statistically significant in the whole group. Retinal ganglion cells function improved as shown by reduced P50 latency (P = 0.04) and increased P50-N95 amplitude (P < 0.0001) of pattern electroretinogram, up to 30 days after the washout (P = 0.01; P = 0.002). Visual evoked potential and retino-cortical time improvement regressed after 30 days of washout. In OAG group, there was any change during the follow-up. No adverse reactions were reported in both groups. Topical citicoline seems to have a neuroprotective action.

  11. Effect of cycloplegia on the refractive status of children: the Shandong children eye study.

    Science.gov (United States)

    Hu, Yuan Yuan; Wu, Jian Feng; Lu, Tai Liang; Wu, Hui; Sun, Wei; Wang, Xing Rong; Bi, Hong Sheng; Jonas, Jost B

    2015-01-01

    To determine the effect of 1% cyclopentolate on the refractive status of children aged 4 to 18 years. Using a random cluster sampling in a cross-sectional school-based study design, children with an age of 4-18 years were selected from kindergardens, primary schools, junior and senior high schools in a rural county and a city. Auto-refractometry was performed before and after inducing cycloplegia which was achieved by 1% cyclopentolate eye drops. Out of 6364 eligible children, data of 5999 (94.3%) children were included in the statistical analysis. Mean age was 10.0±3.3 years (range: 4-18 years). Mean difference between cycloplegic and non-cycloplegic refractive error (DIFF) was 0.78±0.79D (median: 0.50D; range: -1.00D to +10.75D). In univariate analysis, DIFF decreased significantly with older age (Peyes with non-cycloplegic myopia (≤-0.50D) remained myopic after cycloplegia while the remaining 33.6% of eyes became emmetropic (18.0%) or hyperopic (15.7%) under cycloplegia. Prevalence of emmetropia decreased from 37.5% before cycloplegia to 19.8% after cycloplegia while the remaining eyes became hyperopic under cycloplegia. The error committed by using non-cycloplegic versus cycloplegic refractometry in children with mid to dark-brown iris color decreased with older age, and in parallel manner, with more myopic cycloplegic refractive error. Non-cycloplegic refractometric measures lead to a misclassification of refractive error in a significant proportion of children.

  12. Model for Cameron band emission in comets: A case for EPOXI mission target comet 103P/Hartley 2

    CERN Document Server

    Bhardwaj, Anil

    2010-01-01

    The CO2 production rate has been derived in comets using the Cameron band (a3Pi - X1Sigma) emission of CO molecule assuming that photodissociative excitation of CO2 is the main production mechanism of CO in a3Pi metastable state. We have devoloped a model for the production and loss of CO(a3Pi) which has been applied to comet 103P/Hartley 2: the target of EPOXI mission. Our model calculations show that photoelectron impact excitation of CO and dissociative excitation of CO2 can together contribute about 60-90% to the Cameron band emission. The modeled brightness of (0-0) Cameron band emission on comet Hartley 2 is consistent with Hubble Space Telescope observations for 3-5% CO2 (depending on model input solar flux) and 0.5% CO relative to water, where photoelectron impact contribution is about 50-75%. We suggest that estimation of CO2 abundances on comets using Cameron band emission may be reconsidered. We predict the height integrated column brightness of Cameron band of ~1300 R during EPOXI mission encounte...

  13. A new high-speed visual stimulation method for gaze-contingent eye movement and brain activity studies

    Directory of Open Access Journals (Sweden)

    Fabio eRichlan

    2013-07-01

    Full Text Available Approaches using eye movements as markers of ongoing brain activity to investigate perceptual and cognitive processes were able to implement highly sophisticated paradigms driven by eye movement recordings. Crucially, these paradigms involve display changes that have to occur during the time of saccadic blindness, when the subject is unaware of the change. Therefore, a combination of high-speed eye tracking and high-speed visual stimulation is required in these paradigms. For combined eye movement and brain activity studies (e.g., fMRI, EEG, MEG, fast and exact timing of display changes is especially important, because of the high susceptibility of these methods to visual stimulation. Eye tracking systems already achieve sampling rates up to 2000 Hz, but recent LCD technologies for computer screens reduced the temporal resolution to mostly 60 Hz, which is too slow for gaze-contingent display changes. We developed a high-speed video projection system, which is capable of reliably delivering display changes within the time frame of < 5 ms. This could not be achieved even with the fastest CRT monitors available (< 16 ms. The present video projection system facilitates the realization of cutting-edge eye movement research requiring reliable high-speed visual stimulation (e.g., gaze-contingent display changes, short-time presentation, masked priming. Moreover, this system can be used for fast visual presentation in order to assess brain activity using various methods, such as electroencephalography (EEG and functional magnetic resonance imaging (fMRI. The latter technique was previously excluded from high-speed visual stimulation, because it is not possible to operate conventional CRT monitors in the strong magnetic field of an MRI scanner. Therefore, the present video projection system offers new possibilities for studying eye movement-related brain activity using a combination of eye tracking and fMRI.

  14. Neural Control of Voluntary Eye Closure: A Case Study and an fMRI Investigation of Blinking and Winking

    Directory of Open Access Journals (Sweden)

    Martijn G. van Koningsbruggen

    2012-01-01

    Full Text Available The current paper describes a rare case of a patient who suffered from unilateral apraxia of eye closure as a result of a bilateral stroke. Interestingly, the patient’s ability to voluntarily close both eyelids (i.e. blinking was not affected, indicating that different neural mechanisms control each type of eye closure. The stroke caused damage to a large part of the right frontal cortex, including the motor cortex, pre-motor cortex and the frontal eye field (FEF. The lesion in the left hemisphere was restricted to the FEF. In order to further study the neural mechanisms of eye closure, we conducted an fMRI study in a group of neurological healthy subjects. We found that all areas of the oculomotor cortex were activated by both left and right winking, including the FEF, supplementary eye field (SEF, and posterior parietal cortex (PPC. Blinking activated FEF and SEF, but not PPC. Both FEF and PPC were significantly more active during winking than blinking. Together, these results provide evidence for a critical role of the FEF in voluntary unilateral eye closure.

  15. A multicenter, open-label, 52-week study of 2% rebamipide (OPC-12759) ophthalmic suspension in patients with dry eye.

    Science.gov (United States)

    Kinoshita, Shigeru; Awamura, Saki; Nakamichi, Norihiro; Suzuki, Hiroyuki; Oshiden, Kazuhide; Yokoi, Norihiko

    2014-03-01

    To investigate the efficacy and safety of 2% rebamipide ophthalmic suspension administered 4 times daily for 52 weeks in patients with dry eye. Multicenter (17 sites), open-label, single-arm study. A total of 154 patients with dry eye were enrolled in this study. After a 2-week screening period, patients received 2% rebamipide, instilled as 1 drop in each eye, 4 times daily for 52 weeks. The signs and symptoms measures were assessed at baseline, at weeks 2 and 4, and at every 4 weeks thereafter. The objective signs were fluorescein corneal staining score, lissamine green conjunctival staining score, and tear film break-up time, while subjective symptoms were dry eye-related ocular symptoms (foreign body sensation, dryness, photophobia, eye pain, and blurred vision). The safety variable was the occurrence of adverse events. For all objective signs and subjective symptoms, the scores significantly improved at week 2 compared with baseline (P rebamipide is effective in improving both the objective signs and subjective symptoms of dry eye patients for at least 52 weeks. In addition, 2% rebamipide treatment was generally well tolerated. Copyright © 2014. Published by Elsevier Inc.

  16. Effect of cycloplegia on the refractive status of children: the Shandong children eye study.

    Directory of Open Access Journals (Sweden)

    Yuan Yuan Hu

    Full Text Available To determine the effect of 1% cyclopentolate on the refractive status of children aged 4 to 18 years.Using a random cluster sampling in a cross-sectional school-based study design, children with an age of 4-18 years were selected from kindergardens, primary schools, junior and senior high schools in a rural county and a city. Auto-refractometry was performed before and after inducing cycloplegia which was achieved by 1% cyclopentolate eye drops.Out of 6364 eligible children, data of 5999 (94.3% children were included in the statistical analysis. Mean age was 10.0±3.3 years (range: 4-18 years. Mean difference between cycloplegic and non-cycloplegic refractive error (DIFF was 0.78±0.79D (median: 0.50D; range: -1.00D to +10.75D. In univariate analysis, DIFF decreased significantly with older age (P<0.001;correlation coefficient r:-0.24, more hyperopic non-cycloplegic refractive error (P<0.001;r = 0.13 and more hyperopic cycloplegic refractive error (P<0.001;r = 0.49. In multivariate analysis, higher DIFF was associated with higher cycloplegic refractive error (P<0.001; standardized regression coefficient beta:0.50; regression coefficient B: 0.19; 95% confidence interval (CI: 0.18, 0.20, followed by lower intraocular pressure (P<0.001; beta: -0.06; B: -0.02; 95%CI: -0.03, -0.01, rural region of habitation (P = 0.001; beta: -0.04; B: -0.07; 95%CI: -0.11, -0.03, and, to a minor degree, with age (P = 0.006; beta: 0.04; B: 0.009; 95%CI: 0.003, 0.016. 66.4% of all eyes with non-cycloplegic myopia (≤-0.50D remained myopic after cycloplegia while the remaining 33.6% of eyes became emmetropic (18.0% or hyperopic (15.7% under cycloplegia. Prevalence of emmetropia decreased from 37.5% before cycloplegia to 19.8% after cycloplegia while the remaining eyes became hyperopic under cycloplegia.The error committed by using non-cycloplegic versus cycloplegic refractometry in children with mid to dark-brown iris color decreased with older age, and in parallel

  17. [The study of cyclosporin A modified intraocular lens preventing posterior capsular opacification in rabbit eyes].

    Science.gov (United States)

    Teng, H; Zhang, H; Tian, F; Gu, H Q; Liu, X; Sun, J

    2016-02-01

    To investigate the safety and efficacy of cyclosporine A sustained release from modified intraocular lens for preventing posterior capsular opacification (PCO) in rabbit eyes. Forty-five New Zealand albino rabbits undergoing phacoemulsification in their right eyes were randomly and equally divided into three groups. Group A had implanted original IOL, group B had implanted PLGA-IOL(IOL coated with polylactide-glycoli acid), and group C had implanted CsA-PLGA-IOL (CsA loaded PLGA-IOL). All the 45 eyes were examined by a slit-lamp microscope. The intraocular pressures were recorded. Anterior chamber flare and aqueous humor cells were graded at different time point after surgery. The concentrations of CsA in the aqueous humor and blood were determined by high performance liquid chromatography. Anterior segment tissue was histologically examined. Wet posterior capsules were weighed. PCO was graded 6 months later. The mean concentrations of CsA in group C at 2 h,1 d,3 d,7 d,14 d,30 d,60 d after operation were (11.47±2.42) mg/L, (10.30±2.15) mg/L, (6.71±1.45) mg/L, (4.81±1.16) mg/L, (6.11±0.84) mg/L, (2.53±0.77) mg/L, (0.86±0.28) mg/L. The concentrations of CsA in blood were undetectable. During the early days after operation, the reactions of the anterior chamber in group A and B were more severe than group C. The initial appearance of PCO in group C was much later than in the other two groups, and the grade of PCO in group C was much lower than the other two groups. The mean weights of wet posterior capsules in group A(312.86±52.91) mg and B(310.64±62.42) mg were much heavier than that of group C(56.93 ± 24.24) mg. Histological observation showed that there was remarkably less accumulation of lens materials on the posterior capsules in group C than in the other two groups. No toxic actions were found in intraocular tissues in group C. Our study suggested that Cyclosporin A modified intraocular lens could effectively and safely prevent the formation and

  18. The Melaka Hospital cataract complications study analysis of 12,992 eyes.

    Science.gov (United States)

    Thevi, Thanigasalam; Maizura, Zin; Abas, Adinegara Lutfi

    2017-01-01

    As in all surgeries, complications during cataract surgery are unavoidable and cause distress to the surgeon and the patient. This study was conducted to know the factors contributing to complications in our settings, to be able to counsel patients about complications and outcomes and to reduce litigations. The secondary data analysis was conducted using the National Eye Database from 2007 to 2014. Demographic features, ocular comorbidities, technique of surgery, grade of surgeons, types of intraoperative complications, and reasons for not obtaining good visual acuity following intraoperative complications were studied. Statistics was done using Statistical Package for Social Sciences version 20. Out of 12,992 eyes, 6.1% had intraoperative complications. The highest rate of complications was when more trainees (medical officers [MOs] and gazetting specialists) operated. Posterior capsule rupture (PCR) was the most common complication followed by vitreous loss and zonular dehiscence. Those aged below 40 years had more complications (P < 0.05), and females had more complications. Ethnicity did not affect complications. Pseudoexfoliation was the only comorbidity causing complications (P < 0.05). Phacolytic lenses had 8.118 times the odds of getting intraoperative complications. MOs and gazetting specialists got more complications. Good outcomes were obtained in cases without complications and those operated by specialists. High astigmatism was the main reason for poorer outcomes. Intraoperative complications were caused mostly by less experienced doctors and had poorer outcomes. Age below 40 years, females, the presence of pseudoexfoliation and phacolytic lenses had more complications. PCR was the most common complication.

  19. Age-related changes in the macula. A histopathological study of fifty Indian donor eyes

    Directory of Open Access Journals (Sweden)

    Biswas Jyotirmay

    2002-01-01

    Full Text Available PURPOSE: Age-related macular degeneration (ARMD is clinically less common in India compared to the West. Therefore, clinicians are unfamiliar with histopathologic evidence of age-related macular changes in the Indian population. METHODS: Fifty consecutive human donor eyes removed for corneal grafting were studied for gross, microscopic and histochemical features of age-related changes in the macula in the Indian population. A horizontal block was cut from the globe including the optic disc, and the macula. Six sections, 6 microns thick, were cut from three levels in the macula at a distance of 140 microns. These were stained with haemotoxylin-eosin, periodic acid-Schiff, Mallory, Masson trichrome, alcian blue and von Kossa stains. The presence of basal laminar deposits, drusen and thickening and calcification of Bruch′s membrane in the macula were assessed at 400 x magnification using a modified version of Sark′s classification. RESULTS: Twenty-four donor eyes (48% had some form of age-related macular change. These included basal laminar deposits, hard drusen, soft drusen, extensive retinal pigment epithelium atrophy of the macula, and disciform degeneration of macula. A combination of changes was often seen. Age-related changes were more common in the seventh and eighth decade. CONCLUSION: Our study shows that histological changes characteristic of the early stages of age-related macular degeneration are fairly common in the Indian population. However, advanced macular changes are significantly rare.

  20. The bacterial etiology of conjunctivitis in early infancy. Eye Prophylaxis Study Group.

    Science.gov (United States)

    Krohn, M A; Hillier, S L; Bell, T A; Kronmal, R A; Grayston, J T

    1993-09-01

    The authors conducted this study to determine the etiologic agents of conjunctivitis in early infancy. From 1985 to 1990, 630 infants enrolled in a randomized, controlled, double-masked study of eye prophylaxis were observed for 60 days after delivery for signs of conjunctivitis. The following isolates were categorized as pathogens: Haemophilus influenzae, Streptococcus pneumoniae, Neisseria cinerea, Klebsiella pneumoniae, and Chlamydia trachomatis. Using conditional logistic regression for analysis of 97 infant pairs, the authors identified isolates categorized as pathogens almost exclusively among cases (odds ratio (OR) = 18.0, 95% confidence interval (CI) 2.3-128). Among the microorganisms which have not usually been regarded as pathogens in the etiology of infant conjunctivitis, Streptococcus mitis was the only microorganism associated with an increased risk of conjunctivitis (OR = 5.3, 95% CI 1.8-15.0). The findings concerning the species of bacteria most often associated with conjunctivitis, as well as the finding that method of delivery is unimportant, suggest that bacteria were transmitted to the infants' eyes after birth and not from the birth canal.

  1. Cue strength in second-language processing: an eye-tracking study.

    Science.gov (United States)

    Tuninetti, Alba; Warren, Tessa; Tokowicz, Natasha

    2015-01-01

    This study used eye-tracking and grammaticality judgement measures to examine how second-language (L2) learners process syntactic violations in English. Participants were native Arabic and native Mandarin Chinese speakers studying English as an L2, and monolingual English-speaking controls. The violations involved incorrect word order and differed in two ways predicted to be important by the unified competition model [UCM; MacWhinney, B. (2005). A unified model of language acquisition. In J. F. Kroll & A. M. B. de Groot (Eds.), Handbook of bilingualism: Psycholinguistic approaches (pp. 49-67). Oxford: Oxford University Press.]. First, one violation had more and stronger cues to ungrammaticality than the other. Second, the grammaticality of these word orders varied in Arabic and Mandarin Chinese. Sensitivity to violations was relatively quick overall, across all groups. Sensitivity also was related to the number and strength of cues to ungrammaticality regardless of native language, which is consistent with the general principles of the UCM. However, there was little evidence of cross-language transfer effects in either eye movements or grammaticality judgements.

  2. Eye Anatomy

    Science.gov (United States)

    ... News About Us Donate In This Section Eye Anatomy en Español email Send this article to a ... You at Risk For Glaucoma? Childhood Glaucoma Eye Anatomy Five Common Glaucoma Tests Glaucoma Facts and Stats ...

  3. The association of sleep quality with dry eye disease: the Osaka study

    Directory of Open Access Journals (Sweden)

    Kawashima M

    2016-06-01

    Full Text Available Motoko Kawashima,1 Miki Uchino,1,2 Norihiko Yokoi,3 Yuichi Uchino,1,2 Murat Dogru,1 Aoi Komuro,3 Yukiko Sonomura,3 Hiroaki Kato,3 Shigeru Kinoshita,3 Kazuo Tsubota1 1Department of Ophthalmology, Keio University School of Medicine, Shinjuku-ku, 2Ryogoku Eye Clinic, Sumida-ku, Tokyo, 3Department of Ophthalmology, Kyoto Prefectural University of Medicine, Kyoto, Japan Purpose: To investigate the association of dry eye disease with sleep quality. Methods: In 2011, a cross-sectional survey was conducted among all the employees, mainly young and middle-aged Japanese office workers, who used visual display technology, at a company in Osaka, Japan (N=672; age range =26–64 years. The participants were classified according to the Japanese dry eye diagnosis criteria by dry eye examination results including the Schirmer test, fluorescein and lissamine green staining, tear film break-up time, and symptom questionnaire into three groups as follows: definite dry eye disease, probable dry eye disease, and no dry eye disease. To determine sleep quality, Japanese version of the Pittsburgh Sleep Quality Index (global score was implemented. The global score (range =0–21 was calculated by summing seven sleep variable scores (scale, 0–3; scores ≥5.5 indicated poor sleep. Results: The total mean global score was 5.1±2.3 (completed N=383; 45% of the dry eye disease participants reported having poor sleep quality, while 34% of the no dry eye disease participants did so, with a significant difference found in the global score (P=0.002. Furthermore, a statistically significant association was observed between the global score and dry eye disease (P=0.005. Conclusion: Poor sleep quality is associated with dry eye disease, especially with dry eye symptoms. Keywords: dry eye, sleep quality, symptom, questionnaire, Pittsburgh Sleep Quality Index, tear film break-up time, visual display terminals

  4. Size-frequency distribution of boulders ≥10 m on comet 103P/Hartley 2

    Science.gov (United States)

    Pajola, Maurizio; Lucchetti, Alice; Bertini, Ivano; Marzari, Francesco; A'Hearn, Michael F.; La Forgia, Fiorangela; Lazzarin, Monica; Naletto, Giampiero; Barbieri, Cesare

    2016-01-01

    Aims: We derive the size-frequency distribution of boulders on comet 103P/Hartley 2, which are computed from the images taken by the Deep Impact/HRI-V imaging system. We indicate the possible physical processes that lead to these boulder size distributions. Methods: We used images acquired by the High Resolution Imager-Visible CCD camera on 4 November 2010. Boulders ≥10 m were identified and manually extracted from the datasets with the software ArcGIS. We derived the global size-frequency distribution of the illuminated side of the comet (~50%) and identified the power-law indexes characterizing the two lobes of 103P. The three-pixel sampling detection, together with the shadowing of the surface, enables unequivocally detection of boulders scattered all over the illuminated surface. Results: We identify 332 boulders ≥10 m on the imaged surface of the comet, with a global number density of nearly 140/km2 and a cumulative size-frequency distribution represented by a power law with index of -2.7 ± 0.2. The two lobes of 103P show similar indexes, i.e., -2.7 ± 0.2 for the bigger lobe (called L1) and -2.6+ 0.2/-0.5 for the smaller lobe (called L2). The similar power-law indexes and similar maximum boulder sizes derived for the two lobes both point toward a similar fracturing/disintegration phenomena of the boulders as well as similar lifting processes that may occur in L1 and L2. The difference in the number of boulders per km2 between L1 and L2 suggests that the more diffuse H2O sublimation on L1 produce twice the boulders per km2 with respect to those produced on L2 (primary activity CO2 driven). The 103P comet has a lower global power-law index (-2.7 vs. -3.6) with respect to 67P. The global differences between the two comets' activities, coupled with a completely different surface geomorphology, make 103P hardly comparable to 67P. A shape distribution analysis of boulders ≥30 m performed on 103P suggests that the cometary boulders show more elongated shapes

  5. Accurate laser measurements of ozone absorption cross-sections in the Hartley band

    Directory of Open Access Journals (Sweden)

    J. Viallon

    2014-08-01

    Full Text Available Ozone plays a crucial role in tropospheric chemistry, is the third largest contributor to greenhouse radiative forcing after carbon dioxide and methane and also a toxic air pollutant affecting human health and agriculture. Long-term measurements of tropospheric ozone have been performed globally for more than 30 years with UV photometers, all relying on the absorption of ozone at the 253.65 nm line of mercury. We have re-determined this cross-section and report a value of 11.27 × 10−18 cm2 molecule−1 with an expanded relative uncertainty of 0.84 %. This is lower than the conventional value currently in use and measured by Hearn in 1961 with a relative difference of 1.8%, with the consequence that historically reported ozone concentrations should be increased by 1.8%. In order to perform the new measurements of cross sections with reduced uncertainties, a system to generate pure ozone in the gas phase together with an optical system based on a UV laser with lines in the Hartley band, including accurate path length measurement of the absorption cell and a careful evaluation of possible impurities in the ozone sample by mass spectrometry and Fourier Transform Infrared spectroscopy was setup. This resulted in new measurements of absolute values of ozone absorption cross sections of 9.48 × 10−18, 10.44 × 10−18, and 11.07 × 10−18 cm2 molecule−1, with relative expanded uncertainties better than 0.6%, for the wavelengths (in vacuum of 244.062, 248.32, and 257.34 nm respectively. The cross-section at the 253.65 nm line of mercury was determined by comparisons using a Standard Reference Photometer equipped with a mercury lamp as the light source. The newly reported value should be used in the future to obtain the most accurate measurements of ozone concentration, which are in closer agreement with non UV photometry based methods such as the gas phase titration of ozone with nitrogen monoxide.

  6. Accurate measurements of ozone absorption cross-sections in the Hartley band

    Science.gov (United States)

    Viallon, J.; Lee, S.; Moussay, P.; Tworek, K.; Petersen, M.; Wielgosz, R. I.

    2015-03-01

    Ozone plays a crucial role in tropospheric chemistry, is the third largest contributor to greenhouse radiative forcing after carbon dioxide and methane and also a toxic air pollutant affecting human health and agriculture. Long-term measurements of tropospheric ozone have been performed globally for more than 30 years with UV photometers, all relying on the absorption of ozone at the 253.65 nm line of mercury. We have re-determined this cross-section and report a value of 11.27 x 10-18 cm2 molecule-1 with an expanded relative uncertainty of 0.86% (coverage factor k= 2). This is lower than the conventional value currently in use and measured by Hearn (1961) with a relative difference of 1.8%, with the consequence that historically reported ozone concentrations should be increased by 1.8%. In order to perform the new measurements of cross-sections with reduced uncertainties, a system was set up to generate pure ozone in the gas phase together with an optical system based on a UV laser with lines in the Hartley band, including accurate path length measurement of the absorption cell and a careful evaluation of possible impurities in the ozone sample by mass spectrometry and Fourier transform infrared spectroscopy. This resulted in new measurements of absolute values of ozone absorption cross-sections of 9.48 x 10-18, 10.44 x 10-18 and 11.07 x 10-18 cm2 molecule-1, with relative expanded uncertainties better than 0.7%, for the wavelengths (in vacuum) of 244.06, 248.32, and 257.34 nm respectively. The cross-section at the 253.65 nm line of mercury was determined by comparisons using a Standard Reference Photometer equipped with a mercury lamp as the light source. The newly reported value should be used in the future to obtain the most accurate measurements of ozone concentration, which are in closer agreement with non-UV-photometry based methods such as the gas phase titration of ozone with nitrogen monoxide.

  7. Accurate laser measurements of ozone absorption cross-sections in the Hartley band

    Science.gov (United States)

    Viallon, J.; Lee, S.; Moussay, P.; Tworek, K.; Petersen, M.; Wielgosz, R. I.

    2014-08-01

    Ozone plays a crucial role in tropospheric chemistry, is the third largest contributor to greenhouse radiative forcing after carbon dioxide and methane and also a toxic air pollutant affecting human health and agriculture. Long-term measurements of tropospheric ozone have been performed globally for more than 30 years with UV photometers, all relying on the absorption of ozone at the 253.65 nm line of mercury. We have re-determined this cross-section and report a value of 11.27 × 10-18 cm2 molecule-1 with an expanded relative uncertainty of 0.84 %. This is lower than the conventional value currently in use and measured by Hearn in 1961 with a relative difference of 1.8%, with the consequence that historically reported ozone concentrations should be increased by 1.8%. In order to perform the new measurements of cross sections with reduced uncertainties, a system to generate pure ozone in the gas phase together with an optical system based on a UV laser with lines in the Hartley band, including accurate path length measurement of the absorption cell and a careful evaluation of possible impurities in the ozone sample by mass spectrometry and Fourier Transform Infrared spectroscopy was setup. This resulted in new measurements of absolute values of ozone absorption cross sections of 9.48 × 10-18, 10.44 × 10-18, and 11.07 × 10-18 cm2 molecule-1, with relative expanded uncertainties better than 0.6%, for the wavelengths (in vacuum) of 244.062, 248.32, and 257.34 nm respectively. The cross-section at the 253.65 nm line of mercury was determined by comparisons using a Standard Reference Photometer equipped with a mercury lamp as the light source. The newly reported value should be used in the future to obtain the most accurate measurements of ozone concentration, which are in closer agreement with non UV photometry based methods such as the gas phase titration of ozone with nitrogen monoxide.

  8. A Study of Deep CNN-Based Classification of Open and Closed Eyes Using a Visible Light Camera Sensor

    Directory of Open Access Journals (Sweden)

    Ki Wan Kim

    2017-06-01

    Full Text Available The necessity for the classification of open and closed eyes is increasing in various fields, including analysis of eye fatigue in 3D TVs, analysis of the psychological states of test subjects, and eye status tracking-based driver drowsiness detection. Previous studies have used various methods to distinguish between open and closed eyes, such as classifiers based on the features obtained from image binarization, edge operators, or texture analysis. However, when it comes to eye images with different lighting conditions and resolutions, it can be difficult to find an optimal threshold for image binarization or optimal filters for edge and texture extraction. In order to address this issue, we propose a method to classify open and closed eye images with different conditions, acquired by a visible light camera, using a deep residual convolutional neural network. After conducting performance analysis on both self-collected and open databases, we have determined that the classification accuracy of the proposed method is superior to that of existing methods.

  9. Exploring Text and Icon Graph Interpretation in Students with Dyslexia: An Eye-tracking Study.

    Science.gov (United States)

    Kim, Sunjung; Wiseheart, Rebecca

    2017-02-01

    A growing body of research suggests that individuals with dyslexia struggle to use graphs efficiently. Given the persistence of orthographic processing deficits in dyslexia, this study tested whether graph interpretation deficits in dyslexia are directly related to difficulties processing the orthographic components of graphs (i.e. axes and legend labels). Participants were 80 college students with and without dyslexia. Response times and eye movements were recorded as students answered comprehension questions about simple data displayed in bar graphs. Axes and legends were labelled either with words (mixed-modality graphs) or icons (orthography-free graphs). Students also answered informationally equivalent questions presented in sentences (orthography-only condition). Response times were slower in the dyslexic group only for processing sentences. However, eye tracking data revealed group differences for processing mixed-modality graphs, whereas no group differences were found for the orthography-free graphs. When processing bar graphs, students with dyslexia differ from their able reading peers only when graphs contain orthographic features. Implications for processing informational text are discussed. Copyright © 2017 John Wiley & Sons, Ltd.

  10. Does Repeated Ticking Maintain Tic Behavior? An Experimental Study of Eye Blinking in Healthy Individuals

    Directory of Open Access Journals (Sweden)

    Daniel J. V. Beetsma

    2013-01-01

    Full Text Available Tics in Tourette Syndrome (TS are often preceded by 'premonitory urges': annoying feelings or bodily sensations. We hypothesized that, by reducing annoyance of premonitory urges, tic behaviour may be reinforced. In a 2X2 experimental design in healthy participants, we studied the effects of premonitory urges (operationalized as air puffs on the eye and tic behaviour (deliberate eye blinking after a puff or a sound on changes in subjective evaluation of air puffs, and EMG responses on the m. orbicularis oculi. The experimental group with air puffs+ blinking experienced a decrease in subjective annoyance of the air puff, but habituation of the EMG response was blocked and length of EMG response increased. In the control groups (air puffs without instruction to blink, no air puffs, these effects were absent. When extrapolating to the situation in TS patients, these findings suggest that performance of tics is reinforced by reducing the subjective annoyance of premonitory urges, while simultaneously preventing habituation or even inducing sensitisation of the physiological motor response.

  11. Feline eosinophilic keratoconjunctivitis: a retrospective study of 45 cases (56 eyes).

    Science.gov (United States)

    Dean, Eric; Meunier, Valerie

    2013-08-01

    The medical records of 45 cases (56 eyes) of feline eosinophilic keratoconjunctivitis (EKC) diagnosed between 2005 and 2011 were reviewed. Cats were included if a clinical diagnosis of EKC was recorded and eosinophils were found on corneal cytology. Median age at presentation was 5 years (interquartiles 5-9 years) for both males and females. Domestic shorthair was the predominant breed, accounting for 77.8% of the cats. The condition was unilateral in 75.6% of cases, with the superotemporal quadrant of the cornea the most frequently affected position (76.8% of eyes). A history of corneal ulceration was recorded in 37.8% of cases, and corneal ulcers were present at or before diagnosis in 66.7% of the cats. Eosinophils were found in 92.0% of conjunctival scrapings. We performed polymerase chain reaction (PCR) for feline herpesvirus type 1 (FHV-1) for 33/45 cats. Viral DNA was detected in 54.5% of these cats. FHV-1 DNA was detected by PCR in 66.7% of cats with a history and/or presence of a corneal ulcer at first presentation, which is significantly more than those with no corneal ulcer at any time (22.2% FHV-1 DNA detected). Our findings suggest that a corneal ulcer can be present prior to the development of eosinophilic keratitis. Further studies are mandatory to explore the role that FHV-1 could play in EKC-associated corneal ulceration.

  12. Exploring responses to art in adolescence: a behavioral and eye-tracking study.

    Science.gov (United States)

    Savazzi, Federica; Massaro, Davide; Di Dio, Cinzia; Gallese, Vittorio; Gilli, Gabriella; Marchetti, Antonella

    2014-01-01

    Adolescence is a peculiar age mainly characterized by physical and psychological changes that may affect the perception of one's own and others' body. This perceptual peculiarity may influence the way in which bottom-up and top-down processes interact and, consequently, the perception and evaluation of art. This study is aimed at investigating, by means of the eye-tracking technique, the visual explorative behavior of adolescents while looking at paintings. Sixteen color paintings, categorized as dynamic and static, were presented to twenty adolescents; half of the images represented natural environments and half human individuals; all stimuli were displayed under aesthetic and movement judgment tasks. Participants' ratings revealed that, generally, nature images are explicitly evaluated as more appealing than human images. Eye movement data, on the other hand, showed that the human body exerts a strong power in orienting and attracting visual attention and that, in adolescence, it plays a fundamental role during aesthetic experience. In particular, adolescents seem to approach human-content images by giving priority to elements calling forth movement and action, supporting the embodiment theory of aesthetic perception.

  13. Exploring responses to art in adolescence: a behavioral and eye-tracking study.

    Directory of Open Access Journals (Sweden)

    Federica Savazzi

    Full Text Available Adolescence is a peculiar age mainly characterized by physical and psychological changes that may affect the perception of one's own and others' body. This perceptual peculiarity may influence the way in which bottom-up and top-down processes interact and, consequently, the perception and evaluation of art. This study is aimed at investigating, by means of the eye-tracking technique, the visual explorative behavior of adolescents while looking at paintings. Sixteen color paintings, categorized as dynamic and static, were presented to twenty adolescents; half of the images represented natural environments and half human individuals; all stimuli were displayed under aesthetic and movement judgment tasks. Participants' ratings revealed that, generally, nature images are explicitly evaluated as more appealing than human images. Eye movement data, on the other hand, showed that the human body exerts a strong power in orienting and attracting visual attention and that, in adolescence, it plays a fundamental role during aesthetic experience. In particular, adolescents seem to approach human-content images by giving priority to elements calling forth movement and action, supporting the embodiment theory of aesthetic perception.

  14. Physical activity and myopia in Danish children-The CHAMPS Eye Study

    DEFF Research Database (Denmark)

    Lundberg, Kristian; Suhr Thykjær, Anne; Søgaard Hansen, Rasmus

    2017-01-01

    PURPOSE: To determine associations between physical activity (PA) and myopia in Danish school children and investigate the prevalence of myopia. METHODS: This is a prospective study with longitudinal data on PA in a Danish child cohort. Physical activity (PA) was measured objectively by repeated...... ActiGraph accelerometer measurement four times with different intervals (1-2.5 years) at the mean ages 9.7, 11.0, 12.9 and 15.4 years. Mean intensity of PA was estimated as counts/minutes, and time spent in sedentary, light, moderate and vigorous PA was summed using defined cut-off points....... The ophthalmologic examination was conducted at the mean age of 15.4 ± 0.7 years and included cycloplegic autorefraction and biometry. RESULTS: A total of 307 children participated in the Childhood Health, Activity, and Motor Performance School (CHAMPS) Eye Study. The cycloplegic spherical equivalent (SE) was 0...

  15. Degrading traumatic memories with eye movements: a pilot functional MRI study in PTSD

    Science.gov (United States)

    Thomaes, Kathleen; Engelhard, Iris M.; Sijbrandij, Marit; Cath, Danielle C.; Van den Heuvel, Odile A.

    2016-01-01

    Background Eye movement desensitization and reprocessing (EMDR) is an effective treatment for posttraumatic stress disorder (PTSD). During EMDR, the patient recalls traumatic memories while making eye movements (EMs). Making EMs during recall is associated with decreased vividness and emotionality of traumatic memories, but the underlying mechanism has been unclear. Recent studies support a “working-memory” (WM) theory, which states that the two tasks (recall and EMs) compete for limited capacity of WM resources. However, prior research has mainly relied on self-report measures. Methods Using functional magnetic resonance imaging, we tested whether “recall with EMs,” relative to a “recall-only” control condition, was associated with reduced activity of primary visual and emotional processing brain regions, associated with vividness and emotionality respectively, and increased activity of the dorsolateral prefrontal cortex (DLPFC), associated with working memory. We used a randomized, controlled, crossover experimental design in eight adult patients with a primary diagnosis of PTSD. A script-driven imagery (SDI) procedure was used to measure responsiveness to an audio-script depicting the participant's traumatic memory before and after conditions. Results SDI activated mainly emotional processing-related brain regions (anterior insula, rostral anterior cingulate cortex (ACC), and dorsomedial prefrontal cortex), WM-related (DLPFC), and visual (association) brain regions before both conditions. Although predicted pre- to post-test decrease in amygdala activation after “recall with EMs” was not significant, SDI activated less right amygdala and rostral ACC activity after “recall with EMs” compared to post-“recall-only.” Furthermore, functional connectivity from the right amygdala to the rostral ACC was decreased after “recall with EMs” compared with after “recall-only.” Conclusions These preliminary results in a small sample suggest that

  16. OCT Study of Mechanical Properties Associated with Trabecular Meshwork and Collector Channel Motion in Human Eyes

    Science.gov (United States)

    Xin, Chen; Johnstone, Murray; Wang, Ningli; Wang, Ruikang K.

    2016-01-01

    We report the use of a high-resolution optical coherence tomography (OCT) imaging platform to identify and quantify pressure-dependent aqueous outflow system (AOS) tissue relationships and to infer mechanical stiffness through examination of tissue properties in ex vivo human eyes. Five enucleated human eyes are included in this study, with each eye prepared with four equal-sized quadrants, each encompassing 90 degrees of the limbal circumference. In radial limbal segments perfusion pressure within Schlemm’s canal (SC) is controlled by means of a perfusion cannula inserted into the canal lumen, while the other end of the cannula leads to a reservoir at a height that can control the pressure in the cannula. The OCT system images the sample with a spatial resolution of about 5 μm from the trabecular meshwork (TM) surface. Geometric parameters are quantified from the 2D OCT images acquired from the sample subjected to controlled changes in perfusion pressures; parameters include area and height of the lumen of SC, collector channel entrances (CCE) and intrascleral collector channels (ISCC). We show that 3D OCT imaging permits the identification of 3-D relationships of the SC, CCE and ISCC lumen dimensions. Collagen flaps or leaflets are found at CCE that are attached or hinged at only one end, whilst the flaps are connected to the TM by cylindrical structures spanning SC. Increasing static SC pressures resulted in SC lumen enlargement with corresponding enlargement of the CCE and ISCC lumen. Pressure-dependent SC lumen area and height changes are significant at the 0.01 levels for ANOVA, and at the 0.05 for both polynomial curves and Tukey paired comparisons. Dynamic measurements demonstrate a synchronous increase in SC, CCE and ISCC lumen height in response to pressure changes from 0 to 10, 30 or 50 mm Hg, respectively, and the response time is within the 50-millisecond range. From the measured SC volume and corresponding IOP values, we demonstrate that an

  17. The Evonik-Mainz-Eye-Care-Study (EMECS: design and execution of the screening investigation.

    Directory of Open Access Journals (Sweden)

    Lorenz Barleon

    Full Text Available To determine if screening for major ophthalmological diseases is feasible within the frame of routine occupational medicine examinations in a large working population.13037 employees of Evonik Industries aged 40 to 65 years were invited to be screened for major ophthalmological diseases (glaucoma, age related macular degeneration and diabetic retinopathy between June 2007 and March 2008 within an extended setting of occupational medicine. Ophthalmological examinations consisted of visual acuity, objective refraction, pachymetry, tonometry, perimetry (frequency doubling technology, confocal scanning laser ophthalmoscopy and digital fundus photography. Participants responded to a questionnaire addressing history of ocular and general diseases and social history.4183 participants (961 female and 3222 male were examined at 13 different sites. Response rates for eligible persons at those sites ranged from 17.9 to 60.5% but were in part limited by availability of examination slots. Average age of participants was 48.4 ± 5.4 years (mean ± SD. 4147 out of 4183 subjects (99.1% had a visual acuity ≥ 0.5 in the better eye and 3665 out of 4183 (87.6% subjects had a visual acuity ≥ 0.8 in the better eye. 1629 participants (38.9% had previously not been seen by an ophthalmologist at all or not within the last three years.This article describes the study design and basic characteristics of study participants within a large occupational medicine based screening study for ophthalmological diseases. Response rates exceeded expectations and were limiting examination capacity. Meaningful data could be obtained for almost all participants. We reached participants who previously had not received ophthalmic care. Thus, ophthalmological screening appears to be feasible within the frame of routine occupational medicine examinations.

  18. Detection of CO Cameron band emission in comet P/Hartley 2 (1991 XV) with the Hubble Space Telescope

    Science.gov (United States)

    Weaver, H. A.; Feldman, P. D.; Mcphate, J. B.; A'Hearn, M. F.; Arpigny, C.; Smith, T. E.

    1994-01-01

    Ultraviolet (UV) spectra of comet P/Hartley 2 (1991 XV) taken with the Faint Object Spectrograph (FOS) on the Hubble Space Telescope (HST) in 1991 September reveal several bands of the Cameron system of CO (a 3 Pi-X 1 Sigma). These band are most likely due to 'prompt' emission from CO2 and, thus, provide a direct tracer of the CO2 abundance in the nucleus. Photodissociative excitation of CO2 is probably the largest contributor to the Cameron band emission, but significant contributions from electron impact excitation of CO, electron impact dissociation of CO2, and dissociative recombination of CO2(+), are also possible. Using our estimate that photodissociative excitation is responsible for approximately 60% of the total excitation of the Cameron system, we derive Q(sub CO2) approximately 2.6 x 10(exp 27) molecules/s, which implies CO2/H20 approximately 4%. If all of the Cameron band emission is due to photodissociative excitation, then CO2/H2O = 7 +/- 2%. For the largest possible contributions from the other excitation mechanisms considered, the CO2 abundance could be as a small as aproximately 2-3%. We did not detect CO Fourth Positive Group emission in our data and derive an upper limit of CO/H2O less than or equal to 1% (3 sigma) for CO coming directly from the nucleus. Comparison of the relative CO2 and CO abundances in P/Hartley 2 to those in P/Halley (CO2/H2O approximately 3%-4%, CO/H20 approximately 4% for the nucleus source) indicates that selective devolatilization of the nucleus may have occurred for P/Hartley 2. A relatively large CO2/CO ratio (i.e., approximately greater than 1) seems to be a common property of cometary nuclei. Since gas phase chemistry, in either the solar nebula or the interstellar medium (ISM), appears incapable of producing large relative CO2 abundances, the CO2 in cometary nuclei is probably produced either by UV and/or cosmic ray irradiation of ISM grains prior to the formation of the Solar System, or by condensation

  19. Sex differences in risk factors for retinopathy in non-diabetic men and women: The Tromso Eye Study

    DEFF Research Database (Denmark)

    Bertelsen, G.; Peto, T.; Lindekleiv, H.

    2014-01-01

    Purpose: To determine the prevalence and risk factors for retinopathy in a nondiabetic population. Methods: The study population included 5869 participants without diabetes aged 38-87years from the TromsO Eye Study, a substudy of the population-based TromsO Study in Norway. Retinal images from bo...

  20. Processing Control Information in a Nominal Control Construction: An Eye-Tracking Study

    Science.gov (United States)

    Kwon, Nayoung; Sturt, Patrick

    2016-01-01

    In an eye-tracking experiment, we examined the processing of the nominal control construction. Participants' eye-movements were monitored while they read sentences that included either giver control nominals (e.g. "promise" in "Luke's promise to Sophia to photograph himself") or recipient control nominals (e.g. "plea"…

  1. Processing Control Information in a Nominal Control Construction: An Eye-Tracking Study

    Science.gov (United States)

    Kwon, Nayoung; Sturt, Patrick

    2016-01-01

    In an eye-tracking experiment, we examined the processing of the nominal control construction. Participants' eye-movements were monitored while they read sentences that included either giver control nominals (e.g. "promise" in "Luke's promise to Sophia to photograph himself") or recipient control nominals (e.g. "plea"…

  2. Eye-tracking controlled cognitive function tests in patients with amyotrophic lateral sclerosis: a controlled proof-of-principle study.

    Science.gov (United States)

    Keller, Jürgen; Gorges, Martin; Horn, Hannah T; Aho-Özhan, Helena E A; Pinkhardt, Elmar H; Uttner, Ingo; Kassubek, Jan; Ludolph, Albert C; Lulé, Dorothée

    2015-08-01

    Amyotrophic lateral sclerosis (ALS) primarily affects motor and speech abilities. In addition, cognitive functions are impaired in a subset of patients. There is a need to establish an eye movement-based method of neuropsychological assessment suitable for severely physically impaired patients with ALS. Forty-eight ALS patients and thirty-two healthy controls matched for age, sex and education performed a hand and speech motor-free version of the Raven's coloured progressive matrices (CPM) and the D2-test which had been especially adapted for eye-tracking control. Data were compared to a classical motor-dependent paper-pencil version. The association of parameters of the eye-tracking and the paper-pencil version of the tests and the differences between and within groups were studied. Subjects presented similar results in the eye-tracking and the corresponding paper-pencil versions of the CPM and D2-test: a correlation between performance accuracy for the CPM was observed for ALS patients (p < 0.001) and controls (p < 0.001) and in the D2-test for controls (p = 0.048), whereas this correlation did not reach statistical significance for ALS patients (p = 0.096). ALS patients performed worse in the CPM than controls in the eye-tracking (p = 0.053) and the paper-pencil version (p = 0.042). Most importantly, eye-tracking versions of the CPM (p < 0.001) and the D2-test (p = 0.024) reliably distinguished between more and less cognitively impaired patients. Eye-tracking-based neuropsychological testing is a promising approach for assessing cognitive deficits in patients who are unable to speak or write such as patients with severe ALS.

  3. Processing rhythmic pattern during Chinese sentence reading: An eye movement study

    Directory of Open Access Journals (Sweden)

    Yingyi eLuo

    2015-12-01

    Full Text Available Prosodic constraints play a fundamental role during both spoken sentence comprehension and silent reading. In Chinese, the rhythmic pattern of the verb-object (V-O combination has been found to rapidly affect the semantic access/integration process during sentence reading (Luo and Zhou, 2010. Rhythmic pattern refers to the combination of words with different syllabic lengths, with certain combinations disallowed (e.g., [2+1]; numbers standing for the number of syllables of the verb and the noun respectively and certain combinations preferred (e.g., [1+1] or [2+2]. This constraint extends to the situation in which the combination is used to modify other words. A V-O phrase could modify a noun by simply preceding it, forming a V-O-N compound; when the verb is disyllabic, however, the word order has to be O-V-N and the object is preferred to be disyllabic. In this study, we investigated how the reader processes the rhythmic pattern and word order information by recording the reader’s eye-movements. We created four types of sentences by crossing rhythmic pattern and word order in compounding. The compound, embedding a disyllabic verb, could be in the correct O-V-N or the incorrect V-O-N order; the object could be disyllabic or monosyllabic. We found that the reader spent more time and made more regressions on and after the compounds when either type of anomaly was detected during the first pass reading. However, during re-reading (after all the words in the sentence have been viewed, less regressive eye movements were found for the anomalous rhythmic pattern, relative to the correct pattern; moreover, only the abnormal rhythmic pattern, not the violated word order, influenced the regressive eye movements. These results suggest that while the processing of rhythmic pattern and word order information occurs rapidly during the initial reading of the sentence, the process of recovering from the rhythmic pattern anomaly may ease the reanalysis

  4. The Melaka Hospital cataract complications study analysis of 12,992 eyes

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    Thanigasalam Thevi

    2017-01-01

    Full Text Available Introduction: As in all surgeries, complications during cataract surgery are unavoidable and cause distress to the surgeon and the patient. This study was conducted to know the factors contributing to complications in our settings, to be able to counsel patients about complications and outcomes and to reduce litigations. Materials and Methods: The secondary data analysis was conducted using the National Eye Database from 2007 to 2014. Demographic features, ocular comorbidities, technique of surgery, grade of surgeons, types of intraoperative complications, and reasons for not obtaining good visual acuity following intraoperative complications were studied. Statistics was done using Statistical Package for Social Sciences version 20. Results: Out of 12,992 eyes, 6.1% had intraoperative complications. The highest rate of complications was when more trainees (medical officers [MOs] and gazetting specialists operated. Posterior capsule rupture (PCR was the most common complication followed by vitreous loss and zonular dehiscence. Those aged below 40 years had more complications (P < 0.05, and females had more complications. Ethnicity did not affect complications. Pseudoexfoliation was the only comorbidity causing complications (P < 0.05. Phacolytic lenses had 8.118 times the odds of getting intraoperative complications. MOs and gazetting specialists got more complications. Good outcomes were obtained in cases without complications and those operated by specialists. High astigmatism was the main reason for poorer outcomes. Conclusion: Intraoperative complications were caused mostly by less experienced doctors and had poorer outcomes. Age below 40 years, females, the presence of pseudoexfoliation and phacolytic lenses had more complications. PCR was the most common complication.

  5. Obstacle avoidance, visual detection performance, and eye-scanning behavior of glaucoma patients in a driving simulator: a preliminary study.

    Directory of Open Access Journals (Sweden)

    Rocío Prado Vega

    Full Text Available The objective of this study was to evaluate differences in driving performance, visual detection performance, and eye-scanning behavior between glaucoma patients and control participants without glaucoma. Glaucoma patients (n = 23 and control participants (n = 12 completed four 5-min driving sessions in a simulator. The participants were instructed to maintain the car in the right lane of a two-lane highway while their speed was automatically maintained at 100 km/h. Additional tasks per session were: Session 1: none, Session 2: verbalization of projected letters, Session 3: avoidance of static obstacles, and Session 4: combined letter verbalization and avoidance of static obstacles. Eye-scanning behavior was recorded with an eye-tracker. Results showed no statistically significant differences between patients and control participants for lane keeping, obstacle avoidance, and eye-scanning behavior. Steering activity, number of missed letters, and letter reaction time were significantly higher for glaucoma patients than for control participants. In conclusion, glaucoma patients were able to avoid objects and maintain a nominal lane keeping performance, but applied more steering input than control participants, and were more likely than control participants to miss peripherally projected stimuli. The eye-tracking results suggest that glaucoma patients did not use extra visual search to compensate for their visual field loss. Limitations of the study, such as small sample size, are discussed.

  6. Applicability of standard eye-tracking technique in people with intellectual disability: methodological conclusions from a series of studies.

    Science.gov (United States)

    Csákvári, Judit; Gyori, Miklos

    2015-01-01

    Although considerable amount of evidence suggest that info-communication technologies have important potential to promote higher level of adaptive functioning and more efficient learning in people with intellectual disability (ID), very little is known about how people with ID scan visually the visual user interfaces of digital tools. Eye-tracking technique is widely used to study visual scanning processes and is used more and more extensively in assistive and educational technologies, too. Therefore, it is important to explore and understand the limitations and potentials of applying eye-tracking technique in people with ID. The present paper aims this by analyzing data from 4 studies (n=38/38 and n=15/30), via contrasting data from people with ID with data from neurotypical (NT) control subjects along 3 variables, indicative of the applicability of eye-tracking technique. Results strongly suggest that there are specific difficulties in using eye-tracking in people with ID, showing considerable individual variability but depending also on the nature of the actual task. Consequentially, using eye-tracking in this group expectedly requires special considerations and specific solutions.

  7. Pilot Study: The Role of the Hemispheric Lateralization in Mental Disorders by Use of the Limb (Eye, Hand, Foot) Dominance.

    Science.gov (United States)

    Goodarzi, Naser; Dabbaghi, Parviz; Valipour, Habib; Vafadari, Behnam

    2015-04-01

    Based on the previous studies, we know that the hemispheric lateralization defects, increase the probability of psychological disorders. We also know that dominant limb is controlled by dominant hemisphere and limb preference is used as an indicator for hemisphere dominance. In this study we attempted to explore the hemispheric dominance by the use of three limbs (hand, foot and eye). We performed this survey on two samples, psychiatric patients compared with normal population. For this purpose, knowing that the organ dominance is stabilized in adolescence, and age has no effect on the people above 15, we used 48 high school girls and 65 boys as the final samples of normal population. The patient group included 57 male and 26 female who were chronic psychiatric patients. The result shows that left-eye dominance is more in patients than the normal group (P=0.000) but the handedness and footedness differences are not significance. In psychotic, bipolar and depressive disorders, eye dominance had significant difference (P=0.018). But this is not true about hand and foot dominance. Our findings proved that generally in psychiatric patients, left-eye dominance is more common, left-eye dominance is also more in psychotic and depressive disorders. It is less common in bipolar disorders.

  8. The Complex Spin State of 103P-Hartley 2: Kinematics and Orientation in Space

    Science.gov (United States)

    Belton, Michael J. S.; Thomas, Peter; Li, Jian-Yang; Williams, Jade; Carcich, Brian; A'Hearn, Michael F.; McLaughlin, Stephanie; Farnham, Tony; McFadden, Lucy; Lisse, Carey M.; Collins, Steven; Besse, Sebastien; Klaasen, Kenneth; Sunshine, Jessica; Meech, Karen J.; Lindler, Don

    2013-01-01

    We derive the spin state of the nucleus of Comet 103P/Hartley 2, its orientation in space, and its short-term temporal evolution from a mixture of observations taken from the DIXI (Deep Impact Extended Investigation) spacecraft and radar observations. The nucleus is found to spin in an excited long-axis mode (LAM) with its rotational angular momentum per unit mass, M, and rotational energy per unit mass, E, slowly decreasing while the degree of excitation in the spin increases through perihelion passage. M is directed toward (RA, Dec; J2000) = 8+/-+/- 4 deg., 54 +/- 1 deg. (obliquity = 48 +/- 1 deg.). This direction is likely changing, but the change is probably <6 deg. on the sky over the approx. 81.6 days of the DIXI encounter. The magnitudes of M and E at closest approach (JD 2455505.0831866 2011-11-04 13:59:47.310) are 30.0 +/- 0.2 sq. m/s and (1.56 +/- 0.02) X 10(exp -3) sq. m /sq. s respectively. The period of rotation about the instantaneous spin vector, which points in the direction (RA, Dec; J2000) = 300 +/- 3.2deg., 67 +/- 1.3 deg. at the time of closest approach, was 14.1 +/- 0.3 h. The instantaneous spin vector circulates around M, inclined at an average angle of 33.2 +/- 1.3 deg. with an average period of 18.40 +/- 0.13 h at the time of closest approach. The period of roll around the principal axis of minimum inertia (''long'' axis) at that time is 26.72 +/- 0.06 h. The long axis is inclined to M by approx. 81.2 +/- 0.6 deg. on average, slowly decreasing through encounter. We infer that there is a periodic nodding motion of the long axis with half the roll period, i.e., 13.36+/- 0.03 h, with amplitude of 1 again decreasing through encounter. The periodic variability in the circulation and roll rates during a cycle was at the 2% and 10-14% level respectively. During the encounter there was a secular lengthening of the circulation period of the long axis by 1.3 +/- 0.2 min/d, in agreement with ground-based estimates, while the period of roll around the

  9. Parent Perception of Two Eye-Gaze Control Technology Systems in Young Children with Cerebral Palsy: Pilot Study.

    Science.gov (United States)

    Karlsson, Petra; Wallen, Margaret

    2017-01-01

    Eye-gaze control technology enables people with significant physical disability to access computers for communication, play, learning and environmental control. This pilot study used a multiple case study design with repeated baseline assessment and parents' evaluations to compare two eye-gaze control technology systems to identify any differences in factors such as ease of use and impact of the systems for their young children. Five children, aged 3 to 5 years, with dyskinetic cerebral palsy, and their families participated. Overall, families were satisfied with both the Tobii PCEye Go and myGaze® eye tracker, found them easy to position and use, and children learned to operate them quickly. This technology provides young children with important opportunities for learning, play, leisure, and developing communication.

  10. Prevalence of dry eye syndrome at patients with diabetus melitus tip 2, one year retrospective study May 2011-June 2012

    Institute of Scientific and Technical Information of China (English)

    Nora Burda; Vilma Mema; Ejup Mahmudi Md; Brikena Selimi; Sulejman Zhugli; Basri Lenajni; Illaz Bunjaku

    2012-01-01

    Objective: To prescribe and analyze the correlation of Dry Eye and Diabetes Mellitus Tip II, at Polyclinic of Specialties Nr. 2 Ophthalmology service, between May 2011 and June 2012.Methods:A total number of 223 patients diagnosed with Diabetes Mellitus Tip II underwent ocular examinations. 120 male and 103 female, aged from 24-73 years old. To confirm the presence of diabetes among these patients fasting blood glucose level was performed (normal limit < 110 mg/dL). History of disease, duration of diabetes, age, sex was obtained by reviewing the medical records and direct patient interview. Also the patients complains: tearing photophobia, red eye, itching ,foreign body sensation, blurred vision was recorded. From the study were excluded all conditions which affects the tear film stability and contact lens wearer.Results: 118 patients were diagnosed with Dry Eye Syndrome of varying degrees. 58 male/61 female. The diagnosis was made by heaving two or more positive tests performed as mentioned above, and referring to patients complains. Fourteen patients represent pinpoint corneal dye with fluorosceini, forty-six patients was positive to cotton swab test diminution of corneal sensitivity, eighty-nine patients was positive to Schirmmer test less than 10 mm, positive TBUT test less than 9 s was found to be the amount of seventy-one patients. Positive tear meniscus at inferior lid margin was found at fifty-six patients. Dry eye is a disorder of tear film because of tear deficiency or excessive tear evaporation which causes damage to the inter palpaberal ocular surface and is associated with symptoms of ocular discomfort. This ocular disorder is very common among general population with 28% of the adults having dry eye syndrome. Early diagnosis and timely treatment, complications as secondary microbial infection and corneal ulceration could be avoided. Conclusions: In our study the Dry Eye Syndrome showed to have a high correlation with Diabetes Mellitus Tip II (about 52

  11. Accessibility of Referent Information Influences Sentence Planning: An Eye-Tracking Study

    Science.gov (United States)

    Ganushchak, Lesya Y.; Konopka, Agnieszka E.; Chen, Yiya

    2017-01-01

    This study investigated the time-course of online sentence formulation (i.e., incrementality in sentence planning) as a function of the preceding discourse context. In two eye-tracking experiments, participants described pictures of transitive events (e.g., a frog catching a fly). The accessibility of the agent (Experiment 1) and patient (Experiment 2) was manipulated in the discourse preceding each picture. In the Literal condition, participants heard a story where the agent or patient was mentioned explicitly (fly, frog). In the Associative condition, the agent or patient was not mentioned but was primed by the story (via semantically or associatively related words such as insect, small, black, wings). In the No Mention condition, the stories did not explicitly mention or prime either character. The target response was expected to have the same structure and content in all conditions (SVO sentences: The frog catches the fly). The results showed that participants generally looked first at the agent, before speech onset, regardless of condition, and then at the patient around and after speech onset. Analyses of eye movements in time window associated with linguistic planning showed that formulation was sensitive mainly to whether the agent was literally mentioned in the context or not and to lesser extent to conceptual accessibility (Experiment 1). Furthermore, accessibility of the patient (be it literal mention of its name or only availability of the concept) showed no effect on the time-course of utterance planning (Experiment 2). Together, these results suggest that linguistic planning before speech onset was influenced only by the accessibility of the first character name in the sentence, providing further evidence for highly incremental planning in sentence production. PMID:28293201

  12. Expression Profiling of Nonpolar Lipids in Meibum From Patients With Dry Eye: A Pilot Study.

    Science.gov (United States)

    Chen, Jianzhong; Keirsey, Jeremy K; Green, Kari B; Nichols, Kelly K

    2017-04-01

    The purpose of this investigation was to characterize differentially expressed lipids in meibum samples from patients with dry eye disease (DED) in order to better understand the underlying pathologic mechanisms. Meibum samples were collected from postmenopausal women with DED (PW-DED; n = 5) and a control group of postmenopausal women without DED (n = 4). Lipid profiles were analyzed by direct infusion full-scan electrospray ionization mass spectrometry (ESI-MS). An initial analysis of 145 representative peaks from four classes of lipids in PW-DED samples revealed that additional manual corrections for peak overlap and isotopes only slightly affected the statistical analysis. Therefore, analysis of uncorrected data, which can be applied to a greater number of peaks, was used to compare more than 500 lipid peaks common to PW-DED and control samples. Statistical analysis of peak intensities identified several lipid species that differed significantly between the two groups. Data from contact lens wearers with DED (CL-DED; n = 5) were also analyzed. Many species of the two types of diesters (DE) and very long chain wax esters (WE) were decreased by ∼20% in PW-DED, whereas levels of triacylglycerols were increased by an average of 39% ± 3% in meibum from PW-DED compared to that in the control group. Approximately the same reduction (20%) of similar DE and WE was observed for CL-DED. Statistical analysis of peak intensities from direct infusion ESI-MS results identified differentially expressed lipids in meibum from dry eye patients. Further studies are warranted to support these findings.

  13. Accessibility of Referent Information Influences Sentence Planning: An Eye-Tracking Study.

    Science.gov (United States)

    Ganushchak, Lesya Y; Konopka, Agnieszka E; Chen, Yiya

    2017-01-01

    This study investigated the time-course of online sentence formulation (i.e., incrementality in sentence planning) as a function of the preceding discourse context. In two eye-tracking experiments, participants described pictures of transitive events (e.g., a frog catching a fly). The accessibility of the agent (Experiment 1) and patient (Experiment 2) was manipulated in the discourse preceding each picture. In the Literal condition, participants heard a story where the agent or patient was mentioned explicitly (fly, frog). In the Associative condition, the agent or patient was not mentioned but was primed by the story (via semantically or associatively related words such as insect, small, black, wings). In the No Mention condition, the stories did not explicitly mention or prime either character. The target response was expected to have the same structure and content in all conditions (SVO sentences: The frog catches the fly). The results showed that participants generally looked first at the agent, before speech onset, regardless of condition, and then at the patient around and after speech onset. Analyses of eye movements in time window associated with linguistic planning showed that formulation was sensitive mainly to whether the agent was literally mentioned in the context or not and to lesser extent to conceptual accessibility (Experiment 1). Furthermore, accessibility of the patient (be it literal mention of its name or only availability of the concept) showed no effect on the time-course of utterance planning (Experiment 2). Together, these results suggest that linguistic planning before speech onset was influenced only by the accessibility of the first character name in the sentence, providing further evidence for highly incremental planning in sentence production.

  14. A comparison study of visually stimulated brain-computer and eye-tracking interfaces

    Science.gov (United States)

    Suefusa, Kaori; Tanaka, Toshihisa

    2017-06-01

    Objective. Brain-computer interfacing (BCI) based on visual stimuli detects the target on a screen on which a user is focusing. The detection of the gazing target can be achieved by tracking gaze positions with a video camera, which is called eye-tracking or eye-tracking interfaces (ETIs). The two types of interface have been developed in different communities. Thus, little work on a comprehensive comparison between these two types of interface has been reported. This paper quantitatively compares the performance of these two interfaces on the same experimental platform. Specifically, our study is focused on two major paradigms of BCI and ETI: steady-state visual evoked potential-based BCIs and dwelling-based ETIs. Approach. Recognition accuracy and the information transfer rate were measured by giving subjects the task of selecting one of four targets by gazing at it. The targets were displayed in three different sizes (with sides 20, 40 and 60 mm long) to evaluate performance with respect to the target size. Main results. The experimental results showed that the BCI was comparable to the ETI in terms of accuracy and the information transfer rate. In particular, when the size of a target was relatively small, the BCI had significantly better performance than the ETI. Significance. The results on which of the two interfaces works better in different situations would not only enable us to improve the design of the interfaces but would also allow for the appropriate choice of interface based on the situation. Specifically, one can choose an interface based on the size of the screen that displays the targets.

  15. An improved scheme for Flip-OFDM based on Hartley transform in short-range IM/DD systems.

    Science.gov (United States)

    Zhou, Ji; Qiao, Yaojun; Cai, Zhuo; Ji, Yuefeng

    2014-08-25

    In this paper, an improved Flip-OFDM scheme is proposed for IM/DD optical systems, where the modulation/demodulation processing takes advantage of the fast Hartley transform (FHT) algorithm. We realize the improved scheme in one symbol period while conventional Flip-OFDM scheme based on fast Fourier transform (FFT) in two consecutive symbol periods. So the complexity of many operations in improved scheme is half of that in conventional scheme, such as CP operation, polarity inversion and symbol delay. Compared to FFT with complex input constellation, the complexity of FHT with real input constellation is halved. The transmission experiment over 50-km SSMF has been realized to verify the feasibility of improved scheme. In conclusion, the improved scheme has the same BER performance with conventional scheme, but great superiority on complexity.

  16. Unified systolic array for fast computation of the discrete cosine transform, discrete sine transform, and discrete Hartley transform

    Science.gov (United States)

    Pan, Sung B.; Park, Rae-Hong

    1997-12-01

    A two-dimensional (2-D) very large scale integration (VLSI) architecture using a unified systolic array for fast computation of the discrete cosine transform (DCT), the discrete sine transform (DST), and the discrete Hartley transform (DHT) is proposed. The N-point discrete transform is decomposed into even- and odd-numbered frequency samples and they are computed independently at the same time. The proposed unified systolic array architecture can compute the DCT, the DST, and the DHT by defining different coefficient values specific for each transform. We also present another architecture for computation of the DHT, a modified version of the unified systolic array structure, which is faster than the unified architecture by a factor of 2. In addition, the proposed unified architecture can be employed for computation of the inverse DCT (IDCT), the inverse DST (IDST), and the inverse DHT (IDHT) with some modifications.

  17. [N-acetyl-aspartylglutamic acid eye drops in allergic-type conjuctivitis. Double-blind comparative clinical study].

    Science.gov (United States)

    Bonnet, M; Ducournau, D; Lumbroso, P; Serpin, G

    1985-01-01

    Fifty patients with allergic conjunctivitis were included in a double-blind randomized clinical trial designed to compare the efficiency and tolerance of two antiallergic eye-drops: one containing NAAGA (22 patients), the other one containing disodium Cromoglycate (28 patients). Both treatments were used at a dosage of 1 drop 4 times per day. Ocular symptoms, conjunctivo-corneal signs and the subjective ocular condition assessed by the patients themselves with visual analogue scales, were all significantly improved by both eye-drops during the first month of treatment. Statistical analysis showed that patient ocular condition improved more rapidly with NAAGA eye-drops. In 25 patients (12 in the NAAGA group and 13 in the Cromoglycate group), the study was continued for an additional month according to a cross-over protocol. During the 2nd month of treatment, additional improvement of ocular symptoms and signs were observed with both eye-drops but more markedly in those patients who received NAAGA after Cromoglycate. Ocular tolerance was good for both eye-drops.

  18. Psoriasis: an eye opener – a cross-sectional study in a Tertiary Care Hospital of South India

    Directory of Open Access Journals (Sweden)

    Hari Kishan Kumar Yadalla

    2015-01-01

    Full Text Available Introduction: Psoriasis is a multi-system chronic inflammatory skin disease targeting 2% to 3% of the general population. It is a prototype of immune dysregulation mediated by TH1 proinflammatory cytokines such as TNF-α, IFN-gamma, IL-6, and IL-12 with far reaching systemic effects. There is growing and emerging evidence that psoriasis patients have a higher prevalence of associated comorbid diseases, with severe skin disease portends a serious risk for development of these comorbidities and are found to have a higher association of extracutaneous disease manifestations. Aim: To look for eye involvement in psoriasis patients and to evaluate the risk and prognostic factors of disease association. Material and Methods: 200 Patients with psoriasis were screened for any eye involvement after few unusual case presentations with eye complications during the period from September 2013 - August 2014. Results: First case was a post cataract sudden loss of vision secondary to development of uveitis in a female patient aged 52 years, with past history of psoriasis with minimal skin lesions and no arthritis. Another 5 cases of psoriasis with eye involvement were detected during the screening employed in a series of 200 psoriasis cases. Conclusion: The present report highlights the importance of psoriasis and eye involvement, need for collaboration between dermatologists and ophthalmologists for thorough examination and evaluation prior to any surgical intervention and also further long term follow-up studies are warranted for confirmation of this causal relationship.

  19. Small Drusen and Age-Related Macular Degeneration: The Beaver Dam Eye Study

    Directory of Open Access Journals (Sweden)

    Ronald Klein

    2015-03-01

    Full Text Available We tested the hypothesis that large areas of small hard drusen (diameter <63 µm and intermediate drusen (diameter 63–124 µm are associated with the incidence of age-related macular degeneration (AMD. Eyes of 3344 older adults with at least two consecutive visits spaced five years apart over a 20-year period were included. A 6-level severity scale, including no drusen, four levels of increasing area (from minimal (<2596 µm² to large (>9086 µm² of only small hard drusen, and intermediate drusen, was used. The five-year incidence of AMD was 3% in eyes at the start of the interval with no, minimal, small, and moderate areas of only small drusen and 5% and 25% for eyes with large area of only small drusen and intermediate drusen, respectively. Compared to eyes with a moderate area of small drusen, the odds ratio (OR of developing AMD in eyes with a large area of only small drusen was 1.8 (p < 0.001. Compared to eyes with large area of only small drusen, eyes with intermediate drusen had an OR of 5.5 (p < 0.001 of developing AMD. Our results are consistent with our hypothesis that large areas of only small drusen are associated with the incidence of AMD.

  20. The Australian Space Eye: studying the history of galaxy formation with a CubeSat

    CERN Document Server

    Horton, Anthony; Mathers, Naomi; Pektovic, Michael; Griffin, Douglas; Barraclough, Simon; Benson, Craig; Dimitrijevic, Igor; Lambert, Andrew; Previte, Anthony; Bowen, John; Westerman, Solomon; Puig-Suari, Jordi; Reisenfeld, Sam; Lawrence, Jon; Zhelem, Ross; Colless, Matthew; Boyce, Russell

    2016-01-01

    The Australian Space Eye is a proposed astronomical telescope based on a 6U CubeSat platform. The Space Eye will exploit the low level of systematic errors achievable with a small space based telescope to enable high accuracy measurements of the optical extragalactic background light and low surface brightness emission around nearby galaxies. This project is also a demonstrator for several technologies with general applicability to astronomical observations from nanosatellites. Space Eye is based around a 90 mm aperture clear aperture all refractive telescope for broadband wide field imaging in the i and z bands.

  1. The Australian Space Eye: studying the history of galaxy formation with a CubeSat

    Science.gov (United States)

    Horton, Anthony; Spitler, Lee; Mathers, Naomi; Petkovic, Michael; Griffin, Douglas; Barraclough, Simon; Benson, Craig; Dimitrijevic, Igor; Lambert, Andrew; Previte, Anthony; Bowen, John; Westerman, Solomon; Puig-Suari, Jordi; Reisenfeld, Sam; Lawrence, Jon; Zhelem, Ross; Colless, Matthew; Boyce, Russell

    2016-07-01

    The Australian Space Eye is a proposed astronomical telescope based on a 6U CubeSat platform. The Space Eye will exploit the low level of systematic errors achievable with a small space based telescope to enable high accuracy measurements of the optical extragalactic background light and low surface brightness emission around nearby galaxies. This project is also a demonstrator for several technologies with general applicability to astronomical observations from nanosatellites. Space Eye is based around a 90 mm aperture clear aperture all refractive telescope for broadband wide field imaging in the i' and z' bands.

  2. WEB ANALYTICS COMBINED WITH EYE TRACKING FOR SUCCESSFUL USER EXPERIENCE DESIGN: A CASE STUDY

    Directory of Open Access Journals (Sweden)

    Magdalena BORYS

    2016-12-01

    Full Text Available The authors propose a new approach for the mobile user experience design process by means of web analytics and eye-tracking. The proposed method was applied to design the LUT mobile website. In the method, to create the mobile website design, data of various users and their behaviour were gathered and analysed using the web analytics tool. Next, based on the findings from web analytics, the mobile prototype for the website was created and validated in eye-tracking usability testing. The analysis of participants’ behaviour during eye-tracking sessions allowed improvements of the prototype.

  3. Eye-Tracking

    Directory of Open Access Journals (Sweden)

    Gabriela GROSSECK

    2006-01-01

    Full Text Available Eye-tracking: one of the newest and most efficient methods of improving on-line marketing communication is called eye-tracking. Marketers have borrowed this technique, usually used in psychological and medical research, in order to study web users with the help of a video camera incorporated in the monitor.

  4. Benefits of Motion in Animated Storybooks for Children’s Visual Attention and Story Comprehension. An Eye-tracking Study.

    Directory of Open Access Journals (Sweden)

    Zsofia Katalin Takacs

    2016-10-01

    Full Text Available The present study provides experimental evidence regarding 4-6-year-old children’s visual processing of animated versus static illustrations in storybooks. 39 participants listened to an animated and a static book, both three times, while eye movements were registered with an eye-tracker. Outcomes corroborate the hypothesis that specifically motion is what attracts children’s attention while looking at illustrations. It is proposed that animated illustrations that are well matched to the text of the story guide children to those parts of the illustration that are important for understanding the story. This may explain why animated books resulted in better comprehension than static books.

  5. Eye-gaze patterns as students study worked-out examples in mechanics

    Directory of Open Access Journals (Sweden)

    Brian H. Ross

    2010-10-01

    Full Text Available This study explores what introductory physics students actually look at when studying worked-out examples. Our classroom experiences indicate that introductory physics students neither discuss nor refer to the conceptual information contained in the text of worked-out examples. This study is an effort to determine to what extent students incorporate the textual information into the way they study. Student eye-gaze patterns were recorded as they studied the examples to aid them in solving a target problem. Contrary to our expectations from classroom interactions, students spent 40±3% of their gaze time reading the textual information. Their gaze patterns were also characterized by numerous jumps between corresponding mathematical and textual information, implying that they were combining information from both sources. Despite this large fraction of time spent reading the text, student recall of the conceptual information contained therein remained very poor. We also found that having a particular problem in mind had no significant effects on the gaze-patterns or conceptual information retention.

  6. Diabetes eye exams

    Science.gov (United States)

    Diabetic retinopathy - eye exams; Diabetes - eye exams; Glaucoma - diabetic eye exam; Macular edema - diabetic eye exam ... if the doctor who takes care of your diabetes checks your eyes, you need an eye exam ...

  7. What Is Dry Eye?

    Medline Plus

    Full Text Available ... Causes of Dry Eye Dry Eye Treatment What Is Dry Eye? Written By: Kierstan Boyd Reviewed By: ... your eyes do not produce enough tears, it is called dry eye. Dry eye is also when ...

  8. Facts About Pink Eye

    Science.gov (United States)

    ... Information > Pink Eye (Conjunctivitis) > Facts About Pink Eye Facts About Pink Eye Pink eye is one of ... for preventing eye infections. Last Reviewed: November 2015 Fact Sheet Blurb The National Eye Institute (NEI) is ...

  9. Dilating Eye Drops

    Science.gov (United States)

    ... Corneal Abrasions Dilating Eye Drops Lazy eye (defined) Pink eye (defined) Retinopathy of Prematurity Strabismus Stye (defined) Vision ... Corneal Abrasions Dilating Eye Drops Lazy eye (defined) Pink eye (defined) Retinopathy of Prematurity Strabismus Stye (defined) Vision ...

  10. THE EFFECTIVENESS OF PANORAMIC MAPS DESIGN: A PRELIMINARY STUDY BASED ON MOBILE EYE-TRACKING

    Directory of Open Access Journals (Sweden)

    R. Balzarini

    2016-06-01

    Full Text Available This paper presents preliminary results from an ongoing research based on the study of visual attention through mobile eye-tracking techniques. The visual-cognitive approach investigates the reading-comprehension of a particular territorial representation: ski trails maps. The general issue of the study is to provide insights about the effectiveness of panoramic ski maps and more broadly, to suggest innovative efficient representation of the geographic information in mountain. According to some mountain operators, the information provided by paper ski maps no longer meets the needs of a large part of the customers; the question now arises of their adaptation to new digital practices (iPhone, tablets. In a computerized process perspective, this study particularly focuses on the representations, and the inferred information, which are really helpful to the users-skiers to apprehend the territory and make decisions, and which could be effectively replicated into a digital system. The most interesting output relies on the relevance of the panorama view: panorama still fascinates, but contrary to conventional wisdom, the information it provides does not seem to be useful to the skier. From a socio-historical perspective this study shows how empirical evidence-based approach can support the change: our results enhance the discussion on the effectiveness of the message that mountain operators want to convey to the tourist and therefore, on the renewal of (geographical information in ski resorts.

  11. The Effectiveness of Panoramic Maps Design: a Preliminary Study Based on Mobile Eye-Tracking

    Science.gov (United States)

    Balzarini, R.; Murat, M.

    2016-06-01

    This paper presents preliminary results from an ongoing research based on the study of visual attention through mobile eye-tracking techniques. The visual-cognitive approach investigates the reading-comprehension of a particular territorial representation: ski trails maps. The general issue of the study is to provide insights about the effectiveness of panoramic ski maps and more broadly, to suggest innovative efficient representation of the geographic information in mountain. According to some mountain operators, the information provided by paper ski maps no longer meets the needs of a large part of the customers; the question now arises of their adaptation to new digital practices (iPhone, tablets). In a computerized process perspective, this study particularly focuses on the representations, and the inferred information, which are really helpful to the users-skiers to apprehend the territory and make decisions, and which could be effectively replicated into a digital system. The most interesting output relies on the relevance of the panorama view: panorama still fascinates, but contrary to conventional wisdom, the information it provides does not seem to be useful to the skier. From a socio-historical perspective this study shows how empirical evidence-based approach can support the change: our results enhance the discussion on the effectiveness of the message that mountain operators want to convey to the tourist and therefore, on the renewal of (geographical) information in ski resorts.

  12. Pseudoexfoliation: normative data and associations. The Central India Eye and Medical Study.

    Directory of Open Access Journals (Sweden)

    Jost B Jonas

    Full Text Available PURPOSE: To assess the prevalence of pseudoexfoliation (PEX and its associations in a population-based setting. DESIGN: Population-based, cross-sectional study. METHODS: The Central India Eye and Medical Study included 4711 individuals. All study participants underwent a detailed ophthalmological examination. After medical pupil dilation, PEX was assessed by an experienced ophthalmologist using slit-lamp based biomicroscopy. RESULTS: Slit lamp examination results were available for 4646 (98.6% study participants with a mean age of 49.3 ± 13.3 years (range: 30-100 years. PEX was detected in 87 eyes (prevalence: 0.95 ± 0.10% (95%CI: 0.75, 1.15 of 69 subjects (prevalence: 1.49 ± 0.18% (95%CI: 1.14, 1.83. PEX prevalence increased significantly (P<0.001 from 0% in the age group of 30-39 years, to 2.85 ± 0.56% in the age group of 60-69 years, to 6.60 ± 1.21% in the age group of 70-79 years, and to 12.3 ± 4.11% in the age group of 80+ years. In multivariate analysis, PEX prevalence was associated with higher age (P<0.001; regression coefficient B:0.11; odds ratio (OR: 1.11 (95%CI: 1.09, 1.13, lower body mass index (P = 0.001; B: -0.12; OR: 0.88 (95CI: 0.82, 0.95 and higher diastolic blood pressure (P = 0.002; B: 0.02; OR: 1.03 (95%CI: 1.01, 1.04. In the multivariate analysis, PEX was not associated with retinal nerve fiber layer cross section area (P = 0.76 and presence of open-angle glaucoma (P = 0.15. CONCLUSIONS: In a rural Central Indian population aged 30+ years, PEX prevalence (mean: 1.49 ± 0.18% was significantly associated with older age, lower body mass index and higher diastolic blood pressure. It was not significantly associated with optic nerve head measurements, refractive error, any ocular biometric parameter, nuclear cataract, early age-related macular degeneration and retinal vein occlusion, diabetes mellitus, smoking, and dyslipidemia.

  13. A Preliminary Study of Automatic Delineation of Eyes on CT Images Using Ant Colony Optimization

    Institute of Scientific and Technical Information of China (English)

    LI Yong-jie; XIE Wei-fu; YAO De-zhong

    2007-01-01

    Eyes are important organs-at-risk (OARs) that should be protected during the radiation treatment of those head tumors. Correct delineation of the eyes on CT images is one of important issues for treatment planning to protect the eyes as much as possible. In this paper, we propose a new method, named ant colony optimization (ACO), to delineate the eyes automatically.In the proposed algorithm, each ant tries to find a closed path, and some pheromone is deposited on the visited path when the ant finds a path. After all ants finish a circle, the best ant will lay some pheromone to enforce the best path. The proposed algorithm is verified on several CT images, and the preliminary results demonstrate the feasibility of ACO for the delineation problem.

  14. Obstacle avoidance, visual detection performance, and eye-scanning behavior of glaucoma patients in a driving simulator: a preliminary study

    NARCIS (Netherlands)

    Prado Vega, R.; Van Leeuwen, P.M.; Rendon Velez, E.; Lemij, H.G.; De Winter, J.C.

    2013-01-01

    The objective of this study was to evaluate differences in driving performance, visual detection performance, and eye-scanning behavior between glaucoma patients and control participants without glaucoma. Glaucoma patients (n = 23) and control participants (n = 12) completed four 5-min driving sessi

  15. Sensitivity to Speaker Control in the Online Comprehension of Conditional Tips and Promises: An Eye-Tracking Study

    Science.gov (United States)

    Stewart, Andrew J.; Haigh, Matthew; Ferguson, Heather J.

    2013-01-01

    Statements of the form if… then… can be used to communicate conditional speech acts such as tips and promises. Conditional promises require the speaker to have perceived control over the outcome event, whereas conditional tips do not. In an eye-tracking study, we examined whether readers are sensitive to information about perceived speaker control…

  16. Sensitivity to Speaker Control in the Online Comprehension of Conditional Tips and Promises: An Eye-Tracking Study

    Science.gov (United States)

    Stewart, Andrew J.; Haigh, Matthew; Ferguson, Heather J.

    2013-01-01

    Statements of the form if… then… can be used to communicate conditional speech acts such as tips and promises. Conditional promises require the speaker to have perceived control over the outcome event, whereas conditional tips do not. In an eye-tracking study, we examined whether readers are sensitive to information about perceived speaker control…

  17. Obstacle avoidance, visual detection performance, and eye-scanning behavior of glaucoma patients in a driving simulator: a preliminary study

    NARCIS (Netherlands)

    Prado Vega, R.; Van Leeuwen, P.M.; Rendon Velez, E.; Lemij, H.G.; De Winter, J.C.

    2013-01-01

    The objective of this study was to evaluate differences in driving performance, visual detection performance, and eye-scanning behavior between glaucoma patients and control participants without glaucoma. Glaucoma patients (n = 23) and control participants (n = 12) completed four 5-min driving sessi

  18. Your Eyes

    Science.gov (United States)

    ... eyes to see millions of colors. Helping You See It All Rods and cones process the light to give you the total picture. You're ... get cloudy, causing a cataract . A cataract prevents light from reaching the retina and makes it difficult to see. The eyes you have will be yours forever — ...

  19. Eyes - bulging

    Science.gov (United States)

    ... emotional support is important. When to Contact a Medical Professional Call your health care provider if: You have bulging eyes and the cause has not yet been diagnosed. Bulging eyes are accompanied by other symptoms. ... The provider will ask about your medical history and do a physical exam. Some questions ...

  20. Eye-movement study during visual search in Chinese children with developmental dyslexia

    Institute of Scientific and Technical Information of China (English)

    LI Xiu-hong; JING Jin; YANG De-sheng; WANG Hui; WANG Qing-xiong; SONG Shan-shan; FAN Fang

    2013-01-01

    Background Developmental dyslexia (DD) is a disorder in which children with normal intelligence and sensory abilities show learning deficits in reading.Abnormal eye movements have been found in DD.However,eye-movement abnormalities during visual search among Chinese children with DD remain unknown.We aimed to identify the eyemovement characteristics and search efficiency of Chinese children with DD during visual search for targets of different conceptual categories,under same-category conditions.Methods We compared 32 Chinese dyslexic children and 39 non-dyslexic children in visual search tasks,which were assessed using EyeLink Ⅱ High-Speed Eye Tracker (SR Research Ltd.,Canada).Letters,single Chinese characters,digits,Chinese phrases,figures and facial expressions were used as stimuli.Targets were similar to distractors in meaning,phonology and/or shape.Results A main effect of task on visual search scores and all eye-movement parameters were found.Search scores,average saccade amplitude and saccade distance were significantly smaller in the DD group than in the controls.An interaction between group and task was found for pupil diameter.Conclusions Unlike normal readers,children with DD had a reduction in the visual attention span and search accuracy.Besides,children with DD could not increase their mental workload with increase in task difficulty.The conceptual category of the stimulus materials significantly impacts search speed,accuracy and eye-movement parameters.

  1. Selective laser trabeculoplasty in pseudophakic and phakic eyes: a prospective study

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    Myrjam De Keyser

    2017-04-01

    Full Text Available AIM: To compare the efficacy of selective laser trabeculoplasty (SLT in replacing medical therapy in pseudophakic and phakic eyes. METHODS: Subgroup of a prospective randomized clinical trial including patients with primary open angle glaucoma or ocular hypertension controlled with medication. Of 38 pseudophakic eyes were matched with 38 phakic eyes. SLT was offered as a way to decrease medication while maintaining the same low eye pressure. SLT was performed over 360°, at 3ns, spotsize 400 µm, 100 spots. Data [intraocular pressure (IOP, number of medications needed] were measured at 1h, 1wk, 1, 3, 6 and 12mo. An independent-samples t-test was performed to compare baseline characteristics of the phakic and the pseudophakic group and differences in evolution of mean IOP and number of used medications. Chi-squared analysis was performed to investigate proportions of fast, slow and non-responders. RESULTS: The mean IOP measurement was 13.00± 2.88 mm Hg in the phakic group (38 eyes and 13.51± CONCLUSION: IOP lowering effect of SLT is comparable between phakic and pseudophakic eyes.

  2. Inflammation in dry eye associated with rheumatoid arthritis: cytokine and in vivo confocal microscopy study.

    Science.gov (United States)

    Villani, Edoardo; Galimberti, Daniela; Del Papa, Nicoletta; Nucci, Paolo; Ratiglia, Roberto

    2013-01-01

    The purpose of this research was to study ocular surface inflammation in relation to systemic disease activity in rheumatoid arthritis (RA) patients with or without secondary Sjögren's syndrome (SSII and non-SSII respectively). The study was conducted in two phases. In phase I, 12 patients with active RA SSII and 12 with active RA non-SSII were consecutively enrolled. Each completed an Ocular Surface Disease Index (OSDI) questionnaire and underwent a full eye exam and in vivo confocal microscopy examination of the cornea. Tear fluid samples were collected in sponges and analyzed for IL-1α, -6, and -8, and TNF-α. When RA activity was suppressed by systemic treatment the patients entered phase II of the study in which all of the phase I examinations were repeated. In RA SSII patients, OSDI, fluorescein staining dendritic cell density, and concentrations of IL-1α and IL-6 decreased significantly (P < 0.01) between phases I and II. Tear breakup time scores increased significantly. For RA non-SSII patients, there were no significant differences between phases I and II. Differences in the clinical, cellular and cytokine responsiveness to systemic RA treatments show that the ocular surface pathology is dissimilar for RA SSII and RA non-SSII patients.

  3. Estimation of Flavonoid Intake in Older Australians: Secondary Data Analysis of the Blue Mountains Eye Study.

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    Kent, Katherine; Charlton, Karen E; Russell, Joanna; Mitchell, Paul; Flood, Victoria M

    2015-01-01

    Flavonoids, consumed in plant-based foods, have been linked to risk reduction of cancers, cardiovascular, and neurodegenerative diseases. The paucity of information on dietary sources and quantities of flavonoid intake in older adults limits interpretation of epidemiological studies that link flavonoid intake with health outcomes in this population. It was our aim to describe total flavonoid intake, including flavonoid subclasses, in older Australians and to identify rich and commonly consumed sources of flavonoids in this age group. Twelve days of weighed food record dietary data from a subsample of the Blue Mountains Eye Study baseline cohort study of older Australians (n = 79) was analyzed using the US Department of Agriculture flavonoid database. Mean intake of flavonoids was estimated to be 683 mg/day (SD = 507) of which flavan-3-ols contributed 92%, followed by flavonols (4%), flavanones (3%), and flavones (<1%). Black tea was the major flavonoid source, providing 89% of total flavonoid intake. No differences in intake between genders were identified. Dietary intake of flavonoids and flavonoid subclasses in older Australians is similar to the one other estimation of intake in Australian older adults and confirms the types of foods that contribute to flavonoid intake among this sample of older Australians.

  4. Cognitive Food Processing in Binge-Eating Disorder: An Eye-Tracking Study.

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    Sperling, Ingmar; Baldofski, Sabrina; Lüthold, Patrick; Hilbert, Anja

    2017-08-19

    Studies indicate an attentional bias towards food in binge-eating disorder (BED); however, more evidence on attentional engagement and disengagement and processing of multiple attention-competing stimuli is needed. This study aimed to examine visual attention to food and non-food stimuli in BED. In n = 23 participants with full-syndrome and subsyndromal BED and n = 23 individually matched healthy controls, eye-tracking was used to assess attention to food and non-food stimuli during a free exploration paradigm and a visual search task. In the free exploration paradigm, groups did not differ in their initial fixation position. While both groups fixated non-food stimuli significantly longer than food stimuli, the BED group allocated significantly more attention towards food than controls. In the visual search task, groups did not differ in detection times. However, a significant detection bias for food was found in full-syndrome BED, but not in controls. An increased initial attention towards food was related to greater BED symptomatology and lower body mass index (BMI) only in full-syndrome BED, while a greater maintained attention to food was associated with lower BMI in controls. The results suggest food-biased visual attentional processing in adults with BED. Further studies should clarify the implications of attentional processes for the etiology and maintenance of BED.

  5. Our experience with Solcoseryl Eye-Gel in the treatment of corneal lesions. A randomised double-blind study (with 1 color plate).

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    Erbe, W; Herrmann, R; Körner, W F; Rohde-Germann, H; Straub, W

    1984-01-01

    A comparative study of Solcoseryl Eye-Gel versus a 2.4% cysteine eye-gel was carried out under controlled conditions (randomised and double-blind) on a total of 61 patients with corneal lesions (52 foreign body injuries, 9 corneal erosions). The results showed a marked superiority of Solcoseryl Eye-Gel with respect to more rapid healing and also with respect to the possible subsequent development of a corneal macula.

  6. Eye-tracking computer systems for inpatients with tetraplegia: findings from a feasibility study.

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    van Middendorp, J J; Watkins, F; Park, C; Landymore, H

    2014-12-02

    Study design:A longitudinal, prospective, self-controlled cohort study.Objectives:To determine (1) the preliminary benefits of using eye-tracking computer systems (ETCSs) among inpatients with tetraplegia and (2) the feasibility of carrying out a well-powered randomized controlled trial.Setting:Specialist Spinal Cord Injuries Centre, United Kingdom; 6 months during 2013-2014.Methods:Individuals with tetraplegia who were admitted to the center and enrolled in this study were trained and allowed to use the ETCS (Tobii Eyegaze C15 System) twice a week for a duration of 10 weeks. Standardized training modules were developed and offered to all study participants. Study feasibility indicators as well as the Appraisals of Disability: Primary and Secondary Scale, Hospital Anxiety and Depression Scale and the Assistive Technology Device Predisposition Assessment questionnaire scores were taken before and after study enrollment.Results:A total of 31 inpatients with tetraplegia were screened. Although 14 patients (45%) met the study eligibility criteria, 6 patients (19%) consented to be enrolled in the study. Three participants did not complete the planned training schedule because of medical, technical and logistic reasons. Although half of the participants agreed that the ETCS under study was easy to use, no substantial improvements were seen in terms of psychological outcomes, appraisals of disability or independence.Conclusions:The conduct of a controlled trial evaluating the benefits of using ETCSs among newly injured patients with tetraplegia comes with considerable feasibility challenges. Until substantial technical improvements of ETCSs have been implemented, future research should initially focus on those individuals with tetraplegia who are living in the community and who have expressed a need to enhance their computer access and communication skills.Spinal Cord advance online publication, 2 December 2014; doi:10.1038/sc.2014.219.

  7. Rapid eye movement-sleep is reduced in patients with acute uncomplicated diverticulitis—an observational study

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    Chenxi Huang

    2015-08-01

    Full Text Available Introduction. Sleep disturbances are commonly found in patients in the postoperative period. Sleep disturbances may give rise to several complications including cardiopulmonary instability, transient cognitive dysfunction and prolonged convalescence. Many factors including host inflammatory responses are believed to cause postoperative sleep disturbances, as inflammatory responses can alter sleep architecture through cytokine-brain interactions. Our aim was to investigate alteration of sleep architecture during acute infection and its relationships to inflammation and clinical symptoms.Materials & Methods. In this observational study, we included patients with acute uncomplicated diverticulitis as a model to investigate the isolated effects of inflammatory responses on sleep. Eleven patients completed the study. Patients were admitted and treated with antibiotics for two nights, during which study endpoints were measured by polysomnography recordings, self-reported discomfort scores and blood samples of cytokines. One month later, the patients, who now were in complete remission, were readmitted and the endpoints were re-measured (the baseline values.Results. Total sleep time was reduced 4% and 7% the first (p = 0.006 and second (p = 0.014 nights of diverticulitis, compared to baseline, respectively. The rapid eye movement sleep was reduced 33% the first night (p = 0.016, compared to baseline. Moreover, plasma IL-6 levels were correlated to non-rapid eye movement sleep, rapid eye movement sleep and fatigue.Conclusion. Total sleep time and rapid eye movement sleep were reduced during nights with active diverticulitis and correlated with markers of inflammation.

  8. A Monte Carlo study on the effect of the orbital bone to the radiation dose delivered to the eye lens

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    Stratis, Andreas; Zhang, Guozhi; Jacobs, Reinhilde; Bogaerts, Ria; Bosmans, Hilde

    2015-03-01

    The aim of this work was to investigate the influence of backscatter radiation from the orbital bone and the intraorbital fat on the eye lens dose in the dental CBCT energy range. To this end we conducted three different yet interrelated studies; A preliminary simulation study was conducted to examine the impact of a bony layer situated underneath a soft tissue layer on the amount of backscatter radiation. We compared the Percentage Depth Dose (PDD) curves in soft tissue with and without the bone layer and we estimated the depth in tissue where the decrease in backscatter caused by the presence of the bone is noticeable. In a supplementary study, an eye voxel phantom was designed with the DOSxyznrc code. Simulations were performed exposing the phantom at different x-ray energies sequentially in air, in fat tissue and in realistic anatomy with the incident beam perpendicular to the phantom. Finally, a virtual head phantom was implemented into a validated hybrid Monte Carlo (MC) framework to simulate a large Field of View protocol of a real CBCT scanner and examine the influence of scattered dose to the eye lens during the whole rotation of the paired tube-detector system. The results indicated an increase in the dose to the lens due to the fatty tissue in the surrounding anatomy. There is a noticeable dose reduction close to the bone-tissue interface which weakens with increasing distance from the interface, such that the impact of the orbital bone in the eye lens dose becomes small.

  9. Knowledge and attitude for eye diseases and satisfaction for services among urban citizens of Oman: A pilot study

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    Rajiv Khandekar

    2008-01-01

    Materials and Methods: This was a descriptive study. 156 Omani citizens of more than 12 years of age were given a close ended questionnaire. Their self reported responses were collected. Six questions related to cataract, diabetic retinopathy, refractive error, blindness, home treatment, rehabilitation of visually impaired and perception of eye services at Ministry of Health hospitals were asked with three grades of responses to choose from. Results: The knowledge about cataract and diabetic retinopathy was found to be good in more than 70% of respondents. 35% of participants agreed for home treatment of minor eye ailments. The importance of using visual aids and the need to give special facilities for the visually impaired was positive in 85%. Two thirds of the respondents were satisfied with type of eye services. Association of knowledge and satisfaction to the gender and age group was not conclusive. Conclusions: Knowledge regarding cataract surgery and blindness due to diabetes, attitude towards use of spectacles, perceived need for visual rehabilitation and satisfaction with eye care services was positive in more than 60% of the interviewed people in this pilot study. A larger study representing Omani population is recommended.

  10. Degrading traumatic memories with eye movements: a pilot functional MRI study in PTSD

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    Kathleen Thomaes

    2016-11-01

    Full Text Available Background: Eye movement desensitization and reprocessing (EMDR is an effective treatment for posttraumatic stress disorder (PTSD. During EMDR, the patient recalls traumatic memories while making eye movements (EMs. Making EMs during recall is associated with decreased vividness and emotionality of traumatic memories, but the underlying mechanism has been unclear. Recent studies support a “working-memory” (WM theory, which states that the two tasks (recall and EMs compete for limited capacity of WM resources. However, prior research has mainly relied on self-report measures. Methods: Using functional magnetic resonance imaging, we tested whether “recall with EMs,” relative to a “recall-only” control condition, was associated with reduced activity of primary visual and emotional processing brain regions, associated with vividness and emotionality respectively, and increased activity of the dorsolateral prefrontal cortex (DLPFC, associated with working memory. We used a randomized, controlled, crossover experimental design in eight adult patients with a primary diagnosis of PTSD. A script-driven imagery (SDI procedure was used to measure responsiveness to an audio-script depicting the participant's traumatic memory before and after conditions. Results: SDI activated mainly emotional processing-related brain regions (anterior insula, rostral anterior cingulate cortex (ACC, and dorsomedial prefrontal cortex, WM-related (DLPFC, and visual (association brain regions before both conditions. Although predicted pre- to post-test decrease in amygdala activation after “recall with EMs” was not significant, SDI activated less right amygdala and rostral ACC activity after “recall with EMs” compared to post-“recall-only.” Furthermore, functional connectivity from the right amygdala to the rostral ACC was decreased after “recall with EMs” compared with after “recall-only.” Conclusions: These preliminary results in a small sample

  11. Longitudinal Relationship between Axial Length and Height in Chinese Children:Guangzhou Twin Eye Study

    Institute of Scientific and Technical Information of China (English)

    Decai Wang; Chen Zhao; Shengsong Huang; Wenyong Huang; Mingguang He

    2015-01-01

    Purpose:.To understand the growth model of axial length (AL) and height, and to explore the relationship between the two with the passage of time. Methods:.We followed twins in the Guangzhou Twin Eye Study for five years..The AL of both eyes was measured by partial coherence interferometry, and height was measured by a standard scale during each visit..A multivariate multilevel mixed model was adopted for data analysis. Results:.A total of 1217 children were included in the study. Both AL and height increased, but the rate of growth slowed down with age..The mitigation rate of height growth was -0.34 cm/year;.while that of AL growth was -0.01 mm/year. AL was positively related to height,.with a relevant coefficient of R=0.22 (Cov [height intercept, AL intercept] =1.56, 95%CI=1.14 to 1.99). The growth rates of AL and height were al-so positively related, with a relevant coefficient of R=0.18 (Cov [height slope, AL slope] =0.03, 95%CI=0.01 to 0.05). However, taller children had slower rates of height increases, with a relevant coefficient of R=-0.12 (Cov[height intercept, height slope]=-1.33,95%CI=-2.25 to-0.42); but had faster AL growth,.with a relevant coefficient of R=(Cov [height intercept, AL slope] =0.02, 95%CI=-0.05 to 0.08, R=0.02). AL and its growth rate were positively related to each other, with a relevant coefficient of R=(Cov [AL intercept,.AL slope]=0.04, 95%CI=0.03 to 0.05, R=0.3); while the growth rates of AL and height were negatively related to each other, with a relevant coefficient of R=(Cov[AL intercept, height slope]=--0.03 95%CI=-0.16 to 0.1, R=-0.02). Conclusion:.The increase in children's AL is relevant to their height increases..The faster their height increases,.the faster their AL increases.

  12. Principal Component Analysis of Tissue Scores from Substances used in the COLIPA Eye Irritation Validation Study.

    Science.gov (United States)

    Lovell, D P

    1999-06-01

    Principal component analyses (PCA) have been carried out on the tissue scores from Draize eye irritation tests on the 55 formulations and chemical ingredients included in the COLIPA Eye Irritation Validation Study. A PCA was carried out on the tissue scores 24, 48 and 72 hours after instillation of the substances. The first Principal Component (PC I) explained 77% of the total variation in the tissues scores and showed a high negative correlation (r=-0.971) with the scores used to derive the Modified Maximum Average Score (MMAS). The second component (PC II) explained 7% of the total variability and contrasted corneal and iris damage with conjunctival damage as in a similar analysis carried out previously on the ECETOC databank. The third component (PCIII), while only explaining about 3% of the variability, identified individuals treated with formulations that were observed to have low corneal opacity but large corneal area scores. This may represent some particular manner of scoring at the laboratory administering the Draize test or a specific effect of some formulations. A further PCA was carried out on tissue scores from observations at 1hr to 21 days. PC I in this analysis explained 62% of the variability and there was a high negative correlation with the sum of all the tissue scores, while PC II explained 14% of the variability and contrasted damage up to 72 hours with damage after 72 hours. A number of formulations were identified with relatively low MMAS scores but tissue damage that persisted. PCA analysis is thus shown to be a powerful method for exploring complex datasets and for identification of outliers and subgroups. It has shown that the MMAS score captures most of the information on tissue scores in the first 72 hours following exposure, and it is unlikely to be of any advantage in using individual tissue scores for comparisons with alternative tests. The relationship of the classifications schemes used by three alternative methods in the COLIPA

  13. A time study of physicians' work in a German university eye hospital to estimate unit costs.

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    Jan Wolff

    Full Text Available Technical efficiency of hospital services is debated since performance has been heterogeneous. Staff time represents the main resource in patient care and its inappropriate allocation has been identified as a key factor of inefficiency. The aim of this study was to analyse the utilisation of physicians' work time stratified by staff groups, tasks and places of work. A further aim was to use these data to estimate resource use per unit of output.A self-reporting work-sampling study was carried during 14-days at a University Eye Hospital. Staff costs of physicians per unit of output were calculated at the wards, the operating rooms and the outpatient unit.Forty per cent of total work time was spent in contact with the patient. Thirty per cent was spent with documentation tasks. Time spent with documentation tasks declined monotonically with increasing seniority of staff. Unit costs were 56 € per patient day at the wards, 77 € and 20 € per intervention at the operating rooms for inpatients and outpatients, respectively, and 33 € per contact at the outpatient unit. Substantial differences in resources directly dedicated to the patient were found between these locations.The presented data provide unprecedented units costs in inpatient Ophthalmology. Future research should focus on analysing factors that influence differences in time allocation, such as types of patients, organisation of care processes and composition of staff.

  14. Face in profile view reduces perceived facial expression intensity: an eye-tracking study.

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    Guo, Kun; Shaw, Heather

    2015-02-01

    Recent studies measuring the facial expressions of emotion have focused primarily on the perception of frontal face images. As we frequently encounter expressive faces from different viewing angles, having a mechanism which allows invariant expression perception would be advantageous to our social interactions. Although a couple of studies have indicated comparable expression categorization accuracy across viewpoints, it is unknown how perceived expression intensity and associated gaze behaviour change across viewing angles. Differences could arise because diagnostic cues from local facial features for decoding expressions could vary with viewpoints. Here we manipulated orientation of faces (frontal, mid-profile, and profile view) displaying six common facial expressions of emotion, and measured participants' expression categorization accuracy, perceived expression intensity and associated gaze patterns. In comparison with frontal faces, profile faces slightly reduced identification rates for disgust and sad expressions, but significantly decreased perceived intensity for all tested expressions. Although quantitatively viewpoint had expression-specific influence on the proportion of fixations directed at local facial features, the qualitative gaze distribution within facial features (e.g., the eyes tended to attract the highest proportion of fixations, followed by the nose and then the mouth region) was independent of viewpoint and expression type. Our results suggest that the viewpoint-invariant facial expression processing is categorical perception, which could be linked to a viewpoint-invariant holistic gaze strategy for extracting expressive facial cues.

  15. Central corneal thickness in adult Chinese. Association with ocular and general parameters. The Beijing Eye Study.

    Science.gov (United States)

    Zhang, Haitao; Xu, Liang; Chen, Changxi; Jonas, Jost B

    2008-04-01

    To evaluate the distribution of central corneal thickness and its associations in the adult Chinese population. The Beijing Eye Study 2006 is a population-based study including 3,251 (73.3%) subjects (aged 45+ years) out of 4,439 subjects who participated in the survey in 2001 and who returned for re-examination. Central corneal thickness (CCT) measurements were performed by slit lamp-based optical coherence tomography. Central corneal thickness measurement data were available for 3,100 (95.4%) subjects. Mean CCT was 556.2+/-33.1 microm (median: 553 microm; range: 429-688 microm). In multiple regression analysis, CCT was significantly associated with optic disc area (P = 0.043), urban region (P measurements (P measured by pneumotonometry) increased for each microm central corneal thickness increase by 0.03 mmHg. In the adult Chinese population, CCT was significantly associated optic disc area, urban region, and male gender. Intraocular pneumotonometric pressure measurements increased for each microm increase in central corneal thickness by 0.03 mmHg. CCT was not associated with age and refractive error.

  16. Eye-movement study and human performance using telepathology virtual slides: implications for medical education and differences with experience.

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    Krupinski, Elizabeth A; Tillack, Allison A; Richter, Lynne; Henderson, Jeffrey T; Bhattacharyya, Achyut K; Scott, Katherine M; Graham, Anna R; Descour, Michael R; Davis, John R; Weinstein, Ronald S

    2006-12-01

    A core skill in diagnostic pathology is light microscopy. Remarkably little is known about human factors that affect the proficiency of pathologists as light microscopists. The cognitive skills of pathologists have received relatively little attention in comparison with the large literature on human performance studies in radiology. One reason for this lack of formal visual search studies in pathology has been the physical restrictions imposed by the close positioning of a microscope operator's head to the microscope's eyepieces. This blocks access to the operator's eyes and precludes assessment of the microscopist's eye movements. Virtual slide microscopy now removes this barrier and opens the door for studies on human factors and visual search strategies in light microscopy. The aim of this study was to assess eye movements of medical students, pathology residents, and practicing pathologists examining virtual slides on a digital display monitor. Whole histopathology glass slide digital images, so-called virtual slides, of 20 consecutive breast core biopsy cases were used in a retrospective study. These high-quality virtual slides were produced with an array-microscope equipped DMetrix DX-40 ultrarapid virtual slide processor (DMetrix, Tucson, Ariz). Using an eye-tracking device, we demonstrated for the first time that when a virtual slide reader initially looks at a virtual slide his or her eyes are very quickly attracted to regions of interest (ROIs) within the slide and that these ROIs are likely to contain diagnostic information. In a matter of seconds, critical decisions are made on the selection of ROIs for further examination at higher magnification. We recorded: (1) the time virtual slide readers spent fixating on self-selected locations on the video monitor; (2) the characteristics of the ways the eyes jumped between fixation locations; and (3) x and y coordinates for each virtual slide marking the sites the virtual slide readers manually selected for

  17. Variation in genetic admixture and population structure among Latinos: the Los Angeles Latino eye study (LALES

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    Le Marchand Loic

    2009-11-01

    Full Text Available Abstract Background Population structure and admixture have strong confounding effects on genetic association studies. Discordant frequencies for age-related macular degeneration (AMD risk alleles and for AMD incidence and prevalence rates are reported across different ethnic groups. We examined the genomic ancestry characterizing 538 Latinos drawn from the Los Angeles Latino Eye Study [LALES] as part of an ongoing AMD-association study. To help assess the degree of Native American ancestry inherited by Latino populations we sampled 25 Mayans and 5 Mexican Indians collected through Coriell's Institute. Levels of European, Asian, and African descent in Latinos were inferred through the USC Multiethnic Panel (USC MEP, formed from a sample from the Multiethnic Cohort (MEC study, the Yoruba African samples from HapMap II, the Singapore Chinese Health Study, and a prospective cohort from Shanghai, China. A total of 233 ancestry informative markers were genotyped for 538 LALES Latinos, 30 Native Americans, and 355 USC MEP individuals (African Americans, Japanese, Chinese, European Americans, Latinos, and Native Hawaiians. Sensitivity of ancestry estimates to relative sample size was considered. Results We detected strong evidence for recent population admixture in LALES Latinos. Gradients of increasing Native American background and of correspondingly decreasing European ancestry were observed as a function of birth origin from North to South. The strongest excess of homozygosity, a reflection of recent population admixture, was observed in non-US born Latinos that recently populated the US. A set of 42 SNPs especially informative for distinguishing between Native Americans and Europeans were identified. Conclusion These findings reflect the historic migration patterns of Native Americans and suggest that while the 'Latino' label is used to categorize the entire population, there exists a strong degree of heterogeneity within that population, and that

  18. The Impact of Language Opacity and Proficiency on Reading Strategies in Bilinguals: An Eye Movement Study

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    de León Rodríguez, Diego; Buetler, Karin A.; Eggenberger, Noëmi; Laganaro, Marina; Nyffeler, Thomas; Annoni, Jean-Marie; Müri, René M.

    2016-01-01

    Reading strategies vary across languages according to orthographic depth – the complexity of the grapheme in relation to phoneme conversion rules – notably at the level of eye movement patterns. We recently demonstrated that a group of early bilinguals, who learned both languages equally under the age of seven, presented a first fixation location (FFL) closer to the beginning of words when reading in German as compared with French. Since German is known to be orthographically more transparent than French, this suggested that different strategies were being engaged depending on the orthographic depth of the used language. Opaque languages induce a global reading strategy, and transparent languages force a local/serial strategy. Thus, pseudo-words were processed using a local strategy in both languages, suggesting that the link between word forms and their lexical representation may also play a role in selecting a specific strategy. In order to test whether corresponding effects appear in late bilinguals with low proficiency in their second language (L2), we present a new study in which we recorded eye movements while two groups of late German–French and French–German bilinguals read aloud isolated French and German words and pseudo-words. Since, a transparent reading strategy is local and serial, with a high number of fixations per stimuli, and the level of the bilingual participants’ L2 is low, the impact of language opacity should be observed in L1. We therefore predicted a global reading strategy if the bilinguals’ L1 was French (FFL close to the middle of the stimuli with fewer fixations per stimuli) and a local and serial reading strategy if it was German. Thus, the L2 of each group, as well as pseudo-words, should also require a local and serial reading strategy. Our results confirmed these hypotheses, suggesting that global word processing is only achieved by bilinguals with an opaque L1 when reading in an opaque language; the low level in the L2

  19. Establishing the tolerability and performance of tamarind seed polysaccharide (TSP in treating dry eye syndrome: results of a clinical study

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    Valente Cristiana

    2007-03-01

    Full Text Available Abstract Background One of the problems arising from available preparations for dry eye syndrome is the limited residence time of products on the ocular surface. In this paper, we look at an innovative new treatment for dry eye, tamarind seed polysaccharide (TSP. TSP possesses mucomimetic, mucoadhesive and pseudoplastic properties. The 'mucin-like' molecular structure of TSP is similar to corneal and conjunctival mucin 1 (MUC1, a transmembrane glycoprotein thought to play an essential role in protecting and wetting the corneal surface and may explain its increased retention on the eye surface. Methods The activity of TSP and hyaluronic acid (HA in the treatment of dry eye syndrome was compared in an open-label, randomised, single-centre clinical study. Thirty patients were randomised to receive three or more applications per day of either TSP 0.5%, TSP 1% or HA 0.2% (Hyalistil™ over a period of 90 days. The primary objective of tolerability was assessed by visual analogue scale (VAS, scoring of specific symptoms and the incidence of adverse events. Secondary objectives included improvement in stability of the precorneal tear film, subjective symptoms and corneal and conjunctival staining. Results TSP 0.5% and 1% were comparable to HA 0.2% with regard to both primary and secondary objective parameters. TSP 1% showed benefits over HA 0.2% for the subjective symptoms; trouble blinking, ocular burning and foreign body sensation. Conclusion This study suggests that TSP 0.5% and 1% offer at least equivalent relief to HA 0.2% for dry eye syndrome. All treatments demonstrated optimal tolerability and are suitable for frequent use in the therapy of dry eye. TSP 1% produced promising results in terms of improvements in certain patient symptoms and suggests benefits of the TSP formulation. This study paves the way for a larger study to further establish the performance and safety of TSP compared with HA and highlights the need to expand this therapeutic

  20. Fear of blindness and perceptions about blind people. The Andhra Pradesh Eye Disease Study.

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    Giridhar, Pyda; Dandona, Rakhi; Prasad, Mudigonda N; Kovai, Vilas; Dandona, Lalit

    2002-09-01

    This study assessed the fear of being affected by illness and disability including blindness, and perceptions of the population towards blind people in the Indian state of Andhra Pradesh. A total of 11,786 subjects of all ages were sampled from 94 clusters in one urban and three rural study areas of Andhra Pradesh using stratified, random, cluster, systematic sampling to represent the population of this state. A total of 10,293 subjects of all ages underwent a detailed interview and dilated ocular evaluation. Subjects > 15 years of age (7,432) were interviewed regarding fear of illness/disability and their perceptions of blind people. The fear of blindness was assessed in comparison to cancer, severe mental illness, heart attack, losing limbs, deafness, inability to speak, and paralysis. A majority of the study population feared all the illnesses and disabilities assessed. The prevalence of fear of blindness was 90.9% (95% confidence interval 89.1-92.8%) and 92.1% (95% confidence interval 90.6-93.6%) in urban and rural study areas respectively. With multiple logistic regression the fear of blindness was significantly higher for those with any level of education and for those living in the rural study areas. The proportion of those having positive feelings towards blind people was higher in the urban study area. A high prevalence of blindness, 1.84%, has been reported in this population previously. These data suggest that this population feared blindness, and yet there is a high rate of blindness. This reflects the need for increasing awareness about blindness in this population through eye health promotion strategies in order to reduce blindness, and awareness regarding the availability of rehabilitation services.

  1. Eye care infrastructure and human resources for managing diabetic retinopathy in India: The India 11-city 9-state study

    Science.gov (United States)

    Gilbert, Clare E.; Babu, R. Giridhara; Gudlavalleti, Aashrai Sai Venkat; Anchala, Raghupathy; Shukla, Rajan; Ballabh, Pant Hira; Vashist, Praveen; Ramachandra, Srikrishna S.; Allagh, Komal; Sagar, Jayanti; Bandyopadhyay, Souvik; Murthy, G. V. S.

    2016-01-01

    Background: There is a paucity of information on the availability of services for diagnosis and management of diabetic retinopathy (DR) in India. Objectives: The study was undertaken to document existing healthcare infrastructure and practice patterns for managing DR. Methods: This cross-sectional study was conducted in 11 cities and included public and private eye care providers. Both multispecialty and stand-alone eye care facilities were included. Information was collected on the processes used in all steps of the program, from how diabetics were identified for screening through to policies about follow-up after treatment by administering a semistructured questionnaire and by using observational checklists. Results: A total of 86 eye units were included (31.4% multispecialty hospitals; 68.6% stand-alone clinics). The availability of a dedicated retina unit was reported by 68.6% (59) facilities. The mean number of outpatient consultations per year was 45,909 per responding facility, with nearly half being new registrations. A mean of 631 persons with sight-threatening-DR (ST-DR) were registered per year per facility. The commonest treatment for ST-DR was laser photocoagulation. Only 58% of the facilities reported having a full-time retina specialist on their rolls. More than half the eye care facilities (47; 54.6%) reported that their ophthalmologists would like further training in retina. Half (51.6%) of the facilities stated that they needed laser or surgical equipment. About 46.5% of the hospitals had a system to track patients needing treatment or for follow-up. Conclusions: The study highlighted existing gaps in service provision at eye care facilities in India. PMID:27144134

  2. Prevalence and Associations of Steep Cornea/Keratoconus in Greater Beijing. The Beijing Eye Study

    Science.gov (United States)

    Xu, Liang; Wang, Ya Xing; Guo, Yin; You, Qi Sheng; Jonas, Jost B.

    2012-01-01

    Purpose To evaluate the prevalence and associated factors of steep cornea/keratoconus in the adult Chinese population. Methods The population-based Beijing Eye Study 2011 included 3468 individuals with a mean age of 64.6±9.8 years (range: 50–93 years). A detailed ophthalmic examination was performed including optical low-coherence reflectometry. Steep cornea/keratoconus were defined as an anterior corneal refractive power exceeding 48 diopters. Results Mean refractive power of the cornea was 43.16±1.45 diopters (range: 36.51 to 48.46 diopters; flattest meridian) and 43.98±1.52 diopters (range: 37.00 to 52.88 diopters; steepest meridian). A steep cornea/keratoconus defined as corneal refractive power of ≥48 diopters and ≥49 diopters was detected in 27 subjects (prevalence rate: 0.9±0.2%) and 6 (0.2± 0.1%) subjects, respectively. Presence of steep cornea/keratoconus was associated with shorter axial length (Pkeratoconus defined as corneal refractive power of 48+ diopters has a prevalence of 0.9±0.2% among Chinese aged 50 years and above. Its prevalence was significantly associated with the ocular parameters of shorter axial length, smaller interpupillary distance, higher cylindrical and myopic refractive error and lower best corrected visual acuity, however, with none of the systemic parameters tested. PMID:22792169

  3. Effect of Cycloplegia on the Refractive Status of Children: The Shandong Children Eye Study

    Science.gov (United States)

    Hu, Yuan Yuan; Wu, Jian Feng; Lu, Tai Liang; Wu, Hui; Sun, Wei; Wang, Xing Rong

    2015-01-01

    Purpose To determine the effect of 1% cyclopentolate on the refractive status of children aged 4 to 18 years. Methods Using a random cluster sampling in a cross-sectional school-based study design, children with an age of 4–18 years were selected from kindergardens, primary schools, junior and senior high schools in a rural county and a city. Auto-refractometry was performed before and after inducing cycloplegia which was achieved by 1% cyclopentolate eye drops. Results Out of 6364 eligible children, data of 5999 (94.3%) children were included in the statistical analysis. Mean age was 10.0±3.3 years (range: 4–18 years). Mean difference between cycloplegic and non-cycloplegic refractive error (DIFF) was 0.78±0.79D (median: 0.50D; range: -1.00D to +10.75D). In univariate analysis, DIFF decreased significantly with older age (Prefractometry in children with mid to dark-brown iris color decreased with older age, and in parallel manner, with more myopic cycloplegic refractive error. Non-cycloplegic refractometric measures lead to a misclassification of refractive error in a significant proportion of children. PMID:25658329

  4. Novel models for studying the blood-brain and blood-eye barriers in Drosophila.

    Science.gov (United States)

    Pinsonneault, Robert L; Mayer, Nasima; Mayer, Fahima; Tegegn, Nebiyu; Bainton, Roland J

    2011-01-01

    In species as varied as humans and flies, humoral/central nervous system barrier structures are a major obstacle to the passive penetration of small molecules including endogenous compounds, environmental toxins, and drugs. In vivo measurement of blood-brain physiologic function in vertebrate animal models is difficult and current ex vivo models for more rapid experimentation using, for example, cultured brain endothelial cells, only partially reconstitute the anatomy and physiology of a fully intact blood-brain barrier (BBB). To address these problems, we and others continue to develop in vivo assays for studying the complex physiologic function of central nervous system (CNS) barriers using the fruit fly Drosophila melanogaster (Dm). These methods involve the introduction of small molecule reporters of BBB physiology into the fly humoral compartment by direct injection. Since these reporters must cross the Dm BBB in order to be visible in the eye, we can directly assess genetic or chemical modulators of BBB function by monitoring retinal fluorescence. This assay has the advantage of utilizing a physiologically intact BBB in a model organism that is economical and highly amenable to genetic manipulation. In combination with other approaches outlined here, such as brain dissection and behavioral assessment, one can produce a fuller picture of BBB biology and physiology. In this chapter, we provide detailed methods for examining BBB biology in the fly, including a Dm visual assay to screen for novel modulators of the BBB.

  5. Visual attention to plain and ornamented human bodies: an eye-tracking study.

    Science.gov (United States)

    Wohlrab, Silke; Fink, Bernhard; Pyritz, Lennart W; Rahlfs, Moritz; Kappeler, Peter M

    2007-06-01

    Signaling mate quality through visual adornments is a common phenomenon in animals and humans. However, humans are probably the only species who applies artificial ornaments. Such deliberate alterations of the skin, e.g., tattoos and scarring patterns, have been discussed by researchers as potential handicap signals, but there is still very little information about a potential biological signaling value of body modification. In this study eye-tracking was employed to investigate the signaling value of tattoos and other body modification. Measurement of gaze duration of 50 individuals while watching plain, scarred, accessorized, and tattooed bodies of artificial human images indicated that participants looked significantly longer at tattooed than at scarred, accessorized, and plain bodies. Generally, male participants paid more attention to tattooed stimuli of both sexes. More detailed analyses showed that particularly female tattooed stimuli were looked at longer. These findings are discussed within an evolutionary framework by suggesting that tattoos might have some signaling value which influences the perception of both male and female conspecifics and may hence also affect mating decisions.

  6. Children’s and Adolescents’ Processing of Temporary Syntactic Ambiguity: An Eye Movement Study

    Directory of Open Access Journals (Sweden)

    Paul E. Engelhardt

    2014-01-01

    Full Text Available This study examined the eye movements of 24 children and adolescents as they read sentences containing temporary syntactic ambiguities. Prior research suggested that children primarily use grammatical information when making initial parsing decisions, and they tend to disregard semantic and contextual information. On each trial, participants read a garden path sentence (e.g., While the storm blew the boat sat in the shed, and, afterwards, they answered a comprehension question (e.g., Did the storm blow the boat?. The design was 2 × 2 (verb type × ambiguity repeated measures. Verb type was optionally transitive or reflexive, and sentences were ambiguous or unambiguous. Results showed no differences in first pass reading times at the disambiguating verb (e.g., sat. However, regressions did show a significant interaction. The unambiguous-reflexive condition had approximately half the number of regressions, suggesting less processing difficulty in this condition. Developmentally, we found that adolescents had significantly better comprehension, which seemed to be linked to the increased tendency to regress from the disambiguating word. Findings are consistent with the assumption that the processing architecture is more restricted in children compared to adolescents. In addition, results indicated that variance in ambiguity resolution was associated with interference control but not working memory.

  7. Structure modulates similarity-based interference in sluicing: An eye tracking study.

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    Jesse A. Harris

    2015-12-01

    Full Text Available In cue-based content-addressable approaches to memory, a target and its competitors are retrieved in parallel from memory via a fast, associative cue-matching procedure under a severely limited focus of attention. Such a parallel matching procedure could in principle ignore the serial order or hierarchical structure characteristic of linguistic relations. I present an eye tracking while reading experiment that investigates whether the sentential position of a potential antecedent modulates the strength of similarity-based interference, a well-studied effect in which increased similarity in features between a target and its competitors results in slower and less accurate retrieval overall. The manipulation trades on an independently established Locality bias in sluiced structures to associate a wh-remnant (which ones in clausal ellipsis with the most local correlate (some wines, as in The tourists enjoyed some wines, but I don’t know which ones. The findings generally support cue-based parsing models of sentence processing that are subject to similarity-based interference in retrieval, and provide additional support to the growing body of evidence that retrieval is sensitive to both the structural position of a target antecedent and its competitors, and the specificity of retrieval cues.

  8. BARRIERS RESPONSIBLE FOR DELAYED UTILIZATION OF CATARACT SURGERY: AN EYE CAMP STUDY FROM CENTRAL INDIA

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    Umesh

    2014-03-01

    Full Text Available INTRODUCTION: Blindness is one of the significant social problems in India with 7 million of the total 45 million blind people in the world residing in our country. Apart from health and status of vision, there are many other socio-economic factors and perceptions, which influence the decision making of the people for getting operated for cataract. But very few studies have been done on the social factors influencing the utilization of cataract surgery. MATERIAL AND METHODS: It was a hospital-based, descriptive study. The study subjects were recruited from the Ophthalmology department from cataract camp held in Chirayu medical College, Hospital during October 2013 to January 2014. RESULTS: In present study, insufficient family income and no one to accompany (60% and 10% was responded by majority of the subjects. In present study, the barriers for delayed utilization of cataract surgery like could manage to do daily work was responded by 513 (85.5% out of total 600 subjects, could see with the other eye clearly 470 (78.3%, busy with work 118 (19.6%, being female70 (11.6%, fear of surgery 115 (19.1%, old age 200 (33.3%, fear that surgery could lead to loss of eyesight 55 (9.1%, it was Gods will 35 (5.8%, fear about the cost of surgery 375 (62.5% and fear that surgery could lead to death was responded by 15 (2.5% out of total 600 subjects. CONCLUSION: Expansion of outreach programmes to different communities rather than concentrate in urban areas, and offering cataract surgical services at affordable rates will also be of help. Health Education has a great role to play as well, especially in creating awareness. Adequate dissemination of information through various media is usually will be very helpful

  9. Effect of birth parameters on retinal vascular caliber: the Twins Eye Study in Tasmania.

    Science.gov (United States)

    Sun, Cong; Ponsonby, Anne-Louise; Wong, Tien Y; Brown, Shayne A; Kearns, Lisa S; Cochrane, Jenny; MacKinnon, Jane R; Ruddle, Jonathan B; Hewitt, Alex W; Liew, Gerald; Dwyer, Terence; Scurrah, Katrina; Mackey, David A

    2009-03-01

    Recent studies reported an association between smaller birth size and narrower retinal vascular caliber, but it remains unclear whether this association is attributed to confounding by shared environment or genetic factors. At a mean age of 9.3 years, 266 twins (49 monozygotic and 84 dizygotic pairs) in the Twins Eye Study in Tasmania underwent an ophthalmic examination including retinal photography. Retinal vascular caliber was measured using a validated protocol. The majority of these twins were also in the Tasmanian Infant Health Study, which prospectively collected data on birth parameters and antenatal maternal factors. We conducted the main analysis using linear mixed models, accounting for birth set clustering. Both the within-pair (-9.73; 95% CI: -14.68 to -4.77 microm per 5-cm decrease in birth length) and between-pair associations (-7.15; 95% CI: -11.54 to -3.01) with retinal arteriolar caliber were significant and of similar magnitude (difference in effect, P=0.61), after adjusting for age, sex, maternal smoking, mean arterial blood pressure, and other confounders. These associations remained within dizygotic and monozygotic pairs. Analyses of head circumference and retinal arteriolar caliber were similar to those of birth length (within-pair regression coefficient: -2.41; 95% CI: -5.09 to 0.28; between-pair regression coefficient: -2.60; 95% CI: -5.00 to -0.19). For birth weight, only a between-pair association was evident (-7.28; 95% CI: -13.07 to -1.48). This study demonstrates a consistent association between smaller birth size and narrower retinal arterioles in twins. The independent effect of shorter birth length on retinal arteriolar caliber supports a role for twin-specific supply line factors affecting fetal growth on vascular structure.

  10. In Vivo Non-Invasive Measurement of Young's Modulus of Elasticity in Human Eyes: A Feasibility Study.

    Science.gov (United States)

    Sit, Arthur J; Lin, Shuai-Chun; Kazemi, Arash; McLaren, Jay W; Pruet, Christopher M; Zhang, Xiaoming

    2017-08-28

    Abnormal ocular biomechanical properties may be important for understanding the risk of glaucoma. However, there are no clinical methods for measuring standard material properties in patients. In this feasibility study we demonstrated proof-of-principle for a novel method, ultrasound surface wave elastography (USWE), to determine the in vivo Young's modulus of elasticity of corneas in normal human eyes. Twenty eyes of 10 healthy subjects (mean age 51.4±7.2;±SD, range 43-64 y) were studied. A spherical-tipped probe (3-mm diameter) was placed on closed eyelids and generated a gentle harmonic vibration at 100 Hz for 0.1 second. Wave speed propagation in the cornea was measured by USWE, and Young's modulus was calculated from the wave speed. Associations between Young's modulus and intraocular pressure (IOP), age, central corneal thickness, and axial length were explored by Pearson correlation. Statistical significance was determined by using generalized estimating equation models to account for possible correlation between fellow eyes. Mean IOP was 12.8±2.7 mm Hg. Mean wave speed in the cornea was 1.82±0.10 m/s. Young's modulus of elasticity was 696±113 kPa and was correlated with IOP (r=0.57; P=0.004), but none of the other variables (P>0.1). USWE is a novel non-invasive technique for measuring ocular biomechanical properties. Corneal Young's modulus in normal eyes is associated with IOP, consistent with measurements in cadaver eyes. Further work is needed to determine elasticity in other ocular tissues, particularly the sclera, and if elasticity is altered in glaucoma patients.

  11. Genome-wide association studies of quantitatively measured skin, hair, and eye pigmentation in four European populations.

    Directory of Open Access Journals (Sweden)

    Sophie I Candille

    Full Text Available Pigmentation of the skin, hair, and eyes varies both within and between human populations. Identifying the genes and alleles underlying this variation has been the goal of many candidate gene and several genome-wide association studies (GWAS. Most GWAS for pigmentary traits to date have been based on subjective phenotypes using categorical scales. But skin, hair, and eye pigmentation vary continuously. Here, we seek to characterize quantitative variation in these traits objectively and accurately and to determine their genetic basis. Objective and quantitative measures of skin, hair, and eye color were made using reflectance or digital spectroscopy in Europeans from Ireland, Poland, Italy, and Portugal. A GWAS was conducted for the three quantitative pigmentation phenotypes in 176 women across 313,763 SNP loci, and replication of the most significant associations was attempted in a sample of 294 European men and women from the same countries. We find that the pigmentation phenotypes are highly stratified along axes of European genetic differentiation. The country of sampling explains approximately 35% of the variation in skin pigmentation, 31% of the variation in hair pigmentation, and 40% of the variation in eye pigmentation. All three quantitative phenotypes are correlated with each other. In our two-stage association study, we reproduce the association of rs1667394 at the OCA2/HERC2 locus with eye color but we do not identify new genetic determinants of skin and hair pigmentation supporting the lack of major genes affecting skin and hair color variation within Europe and suggesting that not only careful phenotyping but also larger cohorts are required to understand the genetic architecture of these complex quantitative traits. Interestingly, we also see that in each of these four populations, men are more lightly pigmented in the unexposed skin of the inner arm than women, a fact that is underappreciated and may vary across the world.

  12. Electron dose distributions caused by the contact-type metallic eye shield: Studies using Monte Carlo and pencil beam algorithms

    Energy Technology Data Exchange (ETDEWEB)

    Kang, Sei-Kwon; Yoon, Jai-Woong; Hwang, Taejin; Park, Soah; Cheong, Kwang-Ho; Jin Han, Tae; Kim, Haeyoung; Lee, Me-Yeon; Ju Kim, Kyoung, E-mail: kjkim@hallym.or.kr; Bae, Hoonsik

    2015-10-01

    A metallic contact eye shield has sometimes been used for eyelid treatment, but dose distribution has never been reported for a patient case. This study aimed to show the shield-incorporated CT-based dose distribution using the Pinnacle system and Monte Carlo (MC) calculation for 3 patient cases. For the artifact-free CT scan, an acrylic shield machined as the same size as that of the tungsten shield was used. For the MC calculation, BEAMnrc and DOSXYZnrc were used for the 6-MeV electron beam of the Varian 21EX, in which information for the tungsten, stainless steel, and aluminum material for the eye shield was used. The same plan was generated on the Pinnacle system and both were compared. The use of the acrylic shield produced clear CT images, enabling delineation of the regions of interest, and yielded CT-based dose calculation for the metallic shield. Both the MC and the Pinnacle systems showed a similar dose distribution downstream of the eye shield, reflecting the blocking effect of the metallic eye shield. The major difference between the MC and the Pinnacle results was the target eyelid dose upstream of the shield such that the Pinnacle system underestimated the dose by 19 to 28% and 11 to 18% for the maximum and the mean doses, respectively. The pattern of dose difference between the MC and the Pinnacle systems was similar to that in the previous phantom study. In conclusion, the metallic eye shield was successfully incorporated into the CT-based planning, and the accurate dose calculation requires MC simulation.

  13. The use and limits of eye-tracking in high-fidelity clinical scenarios: A pilot study.

    Science.gov (United States)

    Browning, Mark; Cooper, Simon; Cant, Robyn; Sparkes, Louise; Bogossian, Fiona; Williams, Brett; O'Meara, Peter; Ross, Linda; Munro, Graham; Black, Barbara

    2016-03-01

    To explore the potential of mobile eye-tracking to identify healthcare students' area of visual interest and its relationship to performance ratings. Eye-tracking identifies an individual's visual attention focus, and has been used as a training technique in medicine and in nursing. In this study participants wore a point of view (PoV) camera within a spectacle frame during simulation education experiences. Thirty-nine final year nursing and paramedicine students individually participated in three 8 minute clinical simulations with debriefing using videoed eye-tracking recordings. Coloured dots on the video depicted the participant's pupil fixation on five targeted areas. Data extracted from the video camera were collated to report time spent on each target (their 'gaze'). The mean total gaze of expert designated targets in the environment for three 8 minute scenarios was 40-77%. Of 35 participants' focus on three main areas of interest, their priority was the patient's head (34%), the patient's trunk (24%) and their clinical assistant (5%), with significant differences between nursing and paramedic disciplines (P < 0.05). Objectively rated clinical performance improved significantly by the third scenario (P ≤ 0.001). Participants were positive regarding use of eye tracking during debriefing. Eye tracking has the potential to enhance debriefing and educational outcomes, although there are limitations to gaze capture in high fidelity environments and resource cost is high. Further study is warranted to enable better understanding of how expert clinicians achieve high levels of performance. Copyright © 2016 Elsevier Ltd. All rights reserved.

  14. Anticipatory Eye Movements While Watching Continuous Action Across Shots in Video Sequences: A Developmental Study.

    Science.gov (United States)

    Kirkorian, Heather L; Anderson, Daniel R

    2017-07-01

    Eye movements were recorded as 12-month-olds (n = 15), 4-year-olds (n = 17), and adults (n = 19) watched a 15-min video with sequences of shots conveying continuous motion. The central question was whether, and at what age, viewers anticipate the reappearance of objects following cuts to new shots. Adults were more likely than younger viewers to make anticipatory eye movements. Four-year-olds responded to transitions more slowly and tended to fixate the center of the screen. Infants' eye movement patterns reflected a tendency to react rather than anticipate. Findings are consistent with the hypothesis that adults integrate content across shots and understand how space is represented in edited video. Results are interpreted with respect to a developing understanding of film editing due to experience and cognitive maturation. © 2016 The Authors. Child Development © 2016 Society for Research in Child Development, Inc.

  15. Location and composition of haptics of posterior chamber intraocular lenses. Histopathologic study of postmortem eyes.

    Science.gov (United States)

    McDonnell, P J; Champion, R; Green, W R

    1987-02-01

    Of 110 eyes with posterior chamber intraocular lenses (IOLs) examined postmortem, 37% had both haptics outside of the capsular bag; 57% had one haptic in the capsular bag and the other haptic outside of the bag. Typically, these optics were decentered by 1 to 2 mm. Only six eyes (5%) had both haptics within the capsular bag. Erosion into the ciliary sulcus produced obliteration of the major arterial circle of the iris in 12 eyes (11%). The local tissue response to eroding haptics was similar for haptics composed of polypropylene and haptics composed of polymethylmethacrylate (PMMA). The authors found considerable discrepancy between the actual location of haptics and the surgeon's desired location (i.e., capsular bag or ciliary sulcus). Most of these cases were clinically successful.

  16. The perceptual saliency of fearful eyes and smiles: A signal detection study

    Science.gov (United States)

    Saban, Muhammet Ikbal; Rotshtein, Pia

    2017-01-01

    Facial features differ in the amount of expressive information they convey. Specifically, eyes are argued to be essential for fear recognition, while smiles are crucial for recognising happy expressions. In three experiments, we tested whether expression modulates the perceptual saliency of diagnostic facial features and whether the feature’s saliency depends on the face configuration. Participants were presented with masked facial features or noise at perceptual conscious threshold. The task was to indicate whether eyes (experiments 1-3A) or a mouth (experiment 3B) was present. The expression of the face and its configuration (i.e. spatial arrangement of the features) were manipulated. Experiment 1 compared fearful with neutral expressions, experiments 2 and 3 compared fearful versus happy expressions. The detection accuracy data was analysed using Signal Detection Theory (SDT), to examine the effects of expression and configuration on perceptual precision (d’) and response bias (c), separately. Across all three experiments, fearful eyes were detected better (higher d’) than neutral and happy eyes. Eyes were more precisely detected than mouths, whereas smiles were detected better than fearful mouths. The configuration of the features had no consistent effects across the experiments on the ability to detect expressive features. But facial configuration affected consistently the response bias. Participants used a more liberal criterion for detecting the eyes in canonical configuration and fearful expression. Finally, the power in low spatial frequency of a feature predicted its discriminability index. The results suggest that expressive features are perceptually more salient with a higher d’ due to changes at the low-level visual properties, with emotions and configuration affecting perception through top-down processes, as reflected by the response bias. PMID:28267761

  17. Risk factors for decreased visual acuity in preschool children: the multi-ethnic pediatric eye disease and Baltimore pediatric eye disease studies.

    Science.gov (United States)

    Tarczy-Hornoch, Kristina; Varma, Rohit; Cotter, Susan A; McKean-Cowdin, Roberta; Lin, Jesse H; Borchert, Mark S; Torres, Mina; Wen, Ge; Azen, Stanley P; Tielsch, James M; Friedman, David S; Repka, Michael X; Katz, Joanne; Ibironke, Josephine; Giordano, Lydia

    2011-11-01

    To investigate risk factors associated with unilateral or bilateral decreased visual acuity (VA) in preschool children. Population-based, cross-sectional prevalence study. Population-based samples of 6504 children ages 30 to 72 months from California and Maryland. Participants were preschool African-American, Hispanic, and non-Hispanic white children from Los Angeles, California, and Baltimore, Maryland. Data were obtained by a parental interview and a detailed ocular examination. Logistic regression models were used to evaluate the independent associations between demographic, behavioral, and clinical risk factors with unilateral and bilateral decreased VA. Odds ratios (ORs) for various risk factors associated with interocular difference (IOD) in VA of ≥2 lines with ≤20/32 in the worse eye, or bilateral decreased VA preschool children should be considered in light of these risk associations. The authors have no proprietary or commercial interest in any of the materials discussed in this article. Copyright © 2011 American Academy of Ophthalmology. Published by Elsevier Inc. All rights reserved.

  18. Visual attention to emotional face in schizophrenia: an eye tracking study.

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    Mania Asgharpour

    2015-03-01

    Full Text Available Deficits in the processing of facial emotions have been reported extensively in patients with schizophrenia. To explore whether restricted attention is the cause of impaired emotion processing in these patients, we examined visual attention through tracking eye movements in response to emotional and neutral face stimuli in a group of patients with schizophrenia and healthy individuals. We also examined the correlation between visual attention allocation and symptoms severity in our patient group.Thirty adult patients with schizophrenia and 30 matched healthy controls participated in this study. Visual attention data were recorded while participants passively viewed emotional-neutral face pairs for 500 ms. The relationship between the visual attention and symptoms severity were assessed by the Positive and Negative Syndrome Scale (PANSS in the schizophrenia group. Repeated Measures ANOVAs were used to compare the groups.Comparing the number of fixations made during face-pairs presentation, we found that patients with schizophrenia made fewer fixations on faces, regardless of the expression of the face. Analysis of the number of fixations on negative-neutral pairs also revealed that the patients made fewer fixations on both neutral and negative faces. Analysis of number of fixations on positive-neutral pairs only showed more fixations on positive relative to neutral expressions in both groups. We found no correlations between visual attention pattern to faces and symptom severity in schizophrenic patients.The results of this study suggest that the facial recognition deficit in schizophrenia is related to decreased attention to face stimuli. Finding of no difference in visual attention for positive-neutral face pairs between the groups is in line with studies that have shown increased ability to positive emotional perception in these patients.

  19. EVALUATION OF COLOR SETTINGS IN AERIAL IMAGES WITH THE USE OF EYE-TRACKING USER STUDY

    Directory of Open Access Journals (Sweden)

    J. Mirijovsky

    2016-06-01

    Respondents’ answers were evaluated and the most realistic and most preferable color settings were found. The advantage of the eye-tracking evaluation was that also the process of the selection of the answers was analyzed. Areas of Interest were marked around each image in the grid and the sequences of gaze movements were analyzed. Sequence chart was used for visualization and eye-tracking metrics were statistically tested. The presented paper shows the differences in the perception and preferences of aerial images with different color settings.

  20. Tectal codification of eye movements in goldfish studied by electrical microstimulation. f.

    Science.gov (United States)

    Salas, C; Herrero, L; Rodriguez, F; Torres, B

    1997-05-01

    This work compares the tectal codification of eye movements in goldfish with those reported for other vertebrate groups. Focal electrical stimulation was applied in various tectal zones and the characteristics of evoked eye movements were examined as a function of (i) the position of the stimulation over the tectal surface, (ii) the initial position of the eyes and (iii) the parameters (pulse rate, current strength, duration) of the stimulus. In a large medial zone, stimulation within the intermediate and deep layers of the tectum evoked contraversive saccades of both eyes, whose direction and amplitude were roughly congruent with the retinotopic representation of the visual world within overlying layers. These saccades were minimally influenced by the initial position of the eye in the orbit. The topographical arrangement of evoked saccades and body movements suggests that this tectal zone triggers orienting responses in a similar way to those described in other vertebrates. Stimulations applied within the caudal tectum also evoked contraversive saccades, but in disagreement with the overlying retinotopic map--the vertical component was absent. Taken together with electrically evoked body movements reported in free-swimming fish, these saccades could reveal that this zone is involved in escape responses. When stimulations were applied within the anteromedial zone of the tectum, contraversive movements of both eyes appeared much more dependent on initial eye position. Saccades elicited from this area displayed characteristics of "goal-directed saccades" which were similar to those described in the cat. The generation of goal-directed movements from the anteromedial zone suggests that this portion of the goldfish optic tectum has a different intrinsic organization or is connected with the brainstem saccade generator in a different fashion than the medial zone. Finally, stimulation of the extreme anteromedial zone evoked convergent eye movements. These movements and

  1. Peripapillary retinal vessel density in eyes with acute primary angle closure: an optical coherence tomography angiography study.

    Science.gov (United States)

    Wang, Xiaolei; Jiang, Chunhui; Kong, Xiangmei; Yu, Xiaobo; Sun, Xinghuai

    2017-05-01

    The purpose was to investigate peripapillary retinal vessel density in resolved acute primary angle closure (APAC) eyes. This was a prospective, cross-sectional observational study. Thirty-four eyes of 34 patients with unilateral APAC were included, together with the fellow eyes with primary angle closure suspect (PACS) as controls. Peripapillary retinal vessel density was measured using optical coherence tomography (OCT) angiography. Peripapillary retinal vessel density was compared in both eyes and the potential relationship with visual field (VF) test results was evaluated. After an acute attack, the peripapillary retinal vessel density was lower in the APAC than in the PACS eyes (79.3 ± 8.2 versus 85.6 ± 4.9, respectively; P = 0.001). The VF mean deviation (MD) (-7.7 ± 6.7 versus -3.3 ± 1.8 dB, P = 0.002), and the pattern standard deviation (PSD) (4.6 ± 3.3 versus 2.4 ± 0.9 dB, P = 0.001) were worse for the APAC than the PACS eyes, but both had similar thicknesses of the retinal nerve fiber layer (RNFL) (111.8 ± 9.6 versus 114.1 ± 29.1 μm, P = 0.880) and ganglion cell complex (GCC) (94.7 ± 7.5 versus 91.8 ± 9.3 μm, P = 0.328). The peripapillary retinal vessel density was significantly correlated with the VF MD (vessel density: r = 0.455, P = 0.008) and PSD (vessel density: r = -0.592, P density, which was correlated with the VF values. OCT angiography is a reliable method for detecting vascular changes in glaucomatous eyes that show no thinning of the RNFL and GCC.

  2. What Is Dry Eye?

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    Full Text Available ... Español Eye Health / Eye Health A-Z Dry Eye Sections What Is Dry Eye? Dry Eye Symptoms ... Dry Eye Dry Eye Treatment What Is Dry Eye? Written By: Kierstan Boyd Reviewed By: Brenda Pagan- ...

  3. What Is Dry Eye?

    Medline Plus

    Full Text Available ... Español Eye Health / Eye Health A-Z Dry Eye Sections What Is Dry Eye? Dry Eye Symptoms ... Dry Eye Dry Eye Treatment What Is Dry Eye? Leer en Español: ¿Qué Es el Ojo Seco? ...

  4. Recognition of Facial Expressions in Individuals with Elevated Levels of Depressive Symptoms: An Eye-Movement Study

    OpenAIRE

    2012-01-01

    Previous studies consistently reported abnormal recognition of facial expressions in depression. However, it is still not clear whether this abnormality is due to an enhanced or impaired ability to recognize facial expressions, and what underlying cognitive systems are involved. The present study aimed to examine how individuals with elevated levels of depressive symptoms differ from controls on facial expression recognition and to assess attention and information processing using eye trackin...

  5. Comparative Study of Sustained Attentional Bias on Emotional Processing in ADHD Children to Pictures with Eye-Tracking

    OpenAIRE

    Pishyareh, Ebrahim; Mehdi EHRANI-DOOST; MAHMOODI-GHARAIE, Javad; Anahita KHORRAMI; Saeid Reza RAHMDAR

    2015-01-01

    How to Cite This Article: Pishyareh E, Tehrani-doost M, Mahmoodi-gharaie J, Khorrami A, Rahmdar SR. A Comparative Study of SustainedAttentional Bias on Emotional Processing in ADHD Children to Pictures with Eye-Tracking. Iran J Child Neurol. 2015 Winter;9(1):64-70.AbstractObjectiveADHD children have anomalous and negative behavior especially in emotionally related fields when compared to other. Evidence indicates that attention has an impact on emotional processing. The present study evaluate...

  6. About the effect of eye blinking on drug release from pHEMA-based hydrogels: an in vitro study

    OpenAIRE

    Galante, Raquel; Paradiso, Patrizia; Moutinho, Maria Guilhermina; Fernandes, Ana Isabel; Mata, José; Matos, António; Colaço, Rogério; Saramago, Benilde; Serro, Ana Paula

    2015-01-01

    "The development of new ophthalmic drug delivery systems capable of increasing the residence time of drugs in the eye and improve its bioavailability relatively to eyedrops has been object of intense research in recent years. Several studies have shown that drug loaded therapeutic soft contact lenses (SCLs) constitute a promising approach, with several potential advantages as compared with collyria. The main objective of this work is to study the effect of repetitive load and f...

  7. Pilot Study: The Role of the Hemispheric Lateralization in Mental Disorders by Use of the Limb (Eye, Hand, Foot) Dominance

    OpenAIRE

    Goodarzi, Naser; Dabbaghi, Parviz; Valipour, Habib; Vafadari, Behnam

    2015-01-01

    Introduction: Based on the previous studies, we know that the hemispheric lateralization defects, increase the probability of psychological disorders. We also know that dominant limb is controlled by dominant hemisphere and limb preference is used as an indicator for hemisphere dominance. In this study we attempted to explore the hemispheric dominance by the use of three limbs (hand, foot and eye). Methods: We performed this survey on two samples, psychiatric patients compared with normal pop...

  8. Brief Report: Using a Point-of-View Camera to Measure Eye Gaze in Young Children with Autism Spectrum Disorder during Naturalistic Social Interactions--A Pilot Study

    Science.gov (United States)

    Edmunds, Sarah R.; Rozga, Agata; Li, Yin; Karp, Elizabeth A.; Ibanez, Lisa V.; Rehg, James M.; Stone, Wendy L.

    2017-01-01

    Children with autism spectrum disorder (ASD) show reduced gaze to social partners. Eye contact during live interactions is often measured using stationary cameras that capture various views of the child, but determining a child's precise gaze target within another's face is nearly impossible. This study compared eye gaze coding derived from…

  9. Desired and Undesired Effects of Energy Labels--An Eye-Tracking Study.

    Directory of Open Access Journals (Sweden)

    Signe Waechter

    Full Text Available Saving energy is an important pillar for the mitigation of climate change. Electric devices (e.g., freezer and television are an important player in the residential sector in the final demand for energy. Consumers' purchase decisions are therefore crucial to successfully reach the energy-efficiency goals. Putting energy labels on products is often considered an adequate way of empowering consumers to make informed purchase decisions. Consequently, this approach should contribute to reducing overall energy consumption. The effectiveness of its measurement depends on consumers' use and interpretation of the information provided. Despite advances in energy efficiency and a mandatory labeling policy, final energy consumption per capita is in many countries still increasing. This paper provides a systematic analysis of consumers' reactions to one of the most widely used eco-labels, the European Union (EU energy label, by using eye-tracking methodology as an objective measurement. The study's results partially support the EU's mandatory policy, showing that the energy label triggers attention toward energy information in general. However, the energy label's effect on consumers' actual product choices seems to be rather low. The study's results show that the currently used presentation format on the label is insufficient. The findings suggest that it does not facilitate the integration of energy-related information. Furthermore, the current format can attract consumers to focus more on energy-efficiency information, leading them to disregard information about actual energy consumption. As a result, the final energy consumption may increase because excellent ratings on energy efficiency (e.g., A++ do not automatically imply little consumption. Finally, implications for policymakers and suggestions for further research are discussed.

  10. Desired and Undesired Effects of Energy Labels--An Eye-Tracking Study.

    Science.gov (United States)

    Waechter, Signe; Sütterlin, Bernadette; Siegrist, Michael

    2015-01-01

    Saving energy is an important pillar for the mitigation of climate change. Electric devices (e.g., freezer and television) are an important player in the residential sector in the final demand for energy. Consumers' purchase decisions are therefore crucial to successfully reach the energy-efficiency goals. Putting energy labels on products is often considered an adequate way of empowering consumers to make informed purchase decisions. Consequently, this approach should contribute to reducing overall energy consumption. The effectiveness of its measurement depends on consumers' use and interpretation of the information provided. Despite advances in energy efficiency and a mandatory labeling policy, final energy consumption per capita is in many countries still increasing. This paper provides a systematic analysis of consumers' reactions to one of the most widely used eco-labels, the European Union (EU) energy label, by using eye-tracking methodology as an objective measurement. The study's results partially support the EU's mandatory policy, showing that the energy label triggers attention toward energy information in general. However, the energy label's effect on consumers' actual product choices seems to be rather low. The study's results show that the currently used presentation format on the label is insufficient. The findings suggest that it does not facilitate the integration of energy-related information. Furthermore, the current format can attract consumers to focus more on energy-efficiency information, leading them to disregard information about actual energy consumption. As a result, the final energy consumption may increase because excellent ratings on energy efficiency (e.g., A++) do not automatically imply little consumption. Finally, implications for policymakers and suggestions for further research are discussed.

  11. Intraocular pressure and estimated cerebrospinal fluid pressure. The Beijing Eye Study 2011.

    Science.gov (United States)

    Wang, Ya Xing; Jonas, Jost B; Wang, Ningli; You, Qi Sheng; Yang, Diya; Xie, Xiao Bin; Xu, Liang

    2014-01-01

    To examine a potential association between intraocular pressure (IOP) and cerebrospinal fluid pressure (CSFP) in a population-based setting. The population-based Beijing Eye Study 2011 included 3468 individuals with a mean age of 64.6±9.8 years (range: 50-93 years). A detailed ophthalmic examination was performed. Based on a previous study with lumbar cerebrospinal fluid pressure (CSFP) measurements, CSFP was calculated as CSFP [mm Hg] = 0.44×Body Mass Index [kg/m2]+0.16×Diastolic Blood Pressure [mm Hg]-0.18×Age [Years]. In multivariate analysis, IOP was associated with higher estimated CSFP (Pregion of habitation (P<0.001; beta:-0.37; B:-2.78;95%CI:-3.07,-2.48), higher systolic blood pressure (P<0.001; beta: 0.34; B: 0.06;95%CI: 0.05,0.07), higher pulse rate (P = 0.003; beta: 0.05; B: 0.02;95%CI: 0.01,0.03), taller body height (P<0.001; beta: 0.11; B: 0.05;95%CI: 0.03,0.07), higher blood concentration of cholesterol (P = 0.003; beta: 0.05; B: 0.17;95%CI: 0.06,0.28) and higher level of education (P = 0.003; beta: 0.09; B: 0.30;95%CI: 0.16,0.45). IOP was positively associated with estimated CSFP after adjusting for other ocular and systemic parameters. As a corollary, higher estimated CSFP was significantly associated with higher IOP in multivariate analysis. It fits with the notion that the arterial blood pressure, estimated CSFP and IOP are physiologically correlated with each other.

  12. Organic Nano-Grains in Comet 103P/Hartley 2: The Organic Glue of Porous Aggregate Grains?

    Science.gov (United States)

    Wooden, D. H.; Russo, N.Dello; Li, A.; Woodward, C. E.; Kelley, M. S.; Harker, D. E.; Cook, J. C.; Vervack, R. J.; Geballe, T. R.

    2013-01-01

    The GNIRS instrument on the Gemini 8-­-m telescope observed comet 103P/Hartley on 2010-­- Dec-­-04UT, a month after the EPOXI Mission encounter, and detected the 3.3 and 3.4 um bands in emission. The 3.3/3.4 ratio and the broad band widths are consistent with experiments of heated (approximately 600 K) aliphatic carbon (-CH3, -CH2) thin films. For the 3.4 micron band to be in emission, the aliphatic bonds must be attached to a carrier possessing the strongly UV-­-absorbing C=C aromatic rings, and these rings have to be less than 50-­-100 carbon atoms (4-6 Angstrom) for attached -CH bonds to also generate a 3.3 micron-band in emission. Slightly larger (=10Å) Very Small Grains (VSGs) can absorb single UV photons comparable to or exceeding their heat capacity, thermally fluctuate and release IR photon(s). The 3.3 micron and 3.4 micron bands observed by GNIRS suggest that organic macromolecules/ nano-­-grains with both aliphatic and aromatic bonds are fluorescing/thermally fluctuating in the coma. Aliphatic and aromatic materials have been seen in Stardust samples and the primitive carbonaceous chondrite 'Tagish Lake'. The larger the ratio of the -CH2/-CH3 components of the aliphatic 3.4 micron band, the more 'primitive' the organic material. In a Stardust organic globule, some aliphatic bonds were transformed into aromatic bonds during the low dosage of Transmission Electron Microscope imaging. Conversely, lab experiments show irradiation of ices containing small PAHs generates aliphatic organics. Photo-­-processing of ices also likely forms the ubiquitous aliphatic coatings that appear on the surfaces of all silicate subgrains constituting nine cometary interplanetary dust particles. The aliphatic coatings, dominated by -CH2, likely were important in sticking the aggregates together, and existed prior to incorporation of dust aggregates into comet nuclei. These comet aliphatics may be some of the sought-­-after precursors to the more robust and complex

  13. What Is Dry Eye?

    Medline Plus

    Full Text Available ... Eye Symptoms Causes of Dry Eye Dry Eye Treatment What Is Dry Eye? Written By: Kierstan Boyd ... your vision. Privacy Policy Related New Dry Eye Treatment is a Tear-Jerker Jul 21, 2017 Three ...

  14. Diabetic Eye Disease

    Science.gov (United States)

    ... Other Dental Problems Diabetes & Sexual & Urologic Problems Diabetic Eye Disease What is diabetic eye disease? Diabetic eye disease is a group of ... loss can occur. How does diabetes affect my eyes? Diabetes affects your eyes when your blood glucose, ...

  15. Eye-Movement Patterns of Readers with Down Syndrome during Sentence-Processing: An Exploratory Study

    Science.gov (United States)

    Frenck-Mestre, Cheryl; Zardan, Nathalie; Colas, Annie; Ghio, Alain

    2010-01-01

    Eye movements were examined to determine how readers with Down syndrome process sentences online. Participants were 9 individuals with Down syndrome ranging in reading level from Grades 1 to 3 and a reading-level-matched control group. For syntactically simple sentences, the pattern of reading times was similar for the two groups, with longer…

  16. The Effect of Autologous Platelet Lysate Eye Drops: An In Vivo Confocal Microscopy Study

    Directory of Open Access Journals (Sweden)

    Antonio M. Fea

    2016-01-01

    Full Text Available Purpose. To determine the effectiveness of autologous platelet lysate (APL eye drops in patients with primary Sjögren syndrome (SS dry eye, refractory to standard therapy, in comparison with patients treated with artificial tears. We focused on the effect of APL on cornea morphology with the in vivo confocal microscopy (IVCM. Methods. Patients were assigned to two groups: group A used autologous platelet lysate QID, and group B used preservative-free artificial tears QID, for 90 days. Ophthalmological assessments included ocular surface disease index (OSDI, best corrected visual acuity (BCVA, Schirmer test, fluorescein score, and breakup time (BUT. A subgroup of patients in group A underwent IVCM: corneal basal epithelium, subbasal nerves, Langerhans cells, anterior stroma activated keratocytes, and reflectivity were evaluated. Results. 60 eyes of 30 patients were enrolled; in group A (n=20 patients mean OSDI, fluorescein score, and BUT showed significant improvement compared with group B (n=10 patients. The IVCM showed a significant increase in basal epithelium cells density and subbasal nerve plexus density and number and a decrease in Langerhans cells density (p<0.05. Conclusion. APL was found effective in the treatment of SS dry eye. IVCM seems to be a useful tool to visualize cornea morphologic modifications.

  17. Morphosyntactic Development in a Second Language: An Eye-Tracking Study on the Role of Attention

    Science.gov (United States)

    Issa, Bernard Ibrahim, II

    2015-01-01

    One common claim in second language (L2) acquisition research is that attention is crucial for development to occur. Although previous empirical research supports this claim, methodological approaches have not been able to directly measure attention. This thesis utilized eye-tracking to directly measure attention and thus provide converging…

  18. Malignant tumors of the eye and adnexa, morbidity and mortality (population-based study

    Directory of Open Access Journals (Sweden)

    V. M. Merabishvili

    2014-07-01

    Full Text Available For the first time in Russia there are presented data on dynamics of morbidity and mortality from malignant tumors of the eye and adnexa (С69. there were demonstrated details of prevalence by age groups of patients, provided characteristics of dynamics of the levels of morphological verification and distribution of patients by stages of tumor process.

  19. Towards Diagram Understanding: A Pilot Study Measuring Cognitive Workload Through Eye-Tracking

    DEFF Research Database (Denmark)

    Maier, Anja; Baltsen, Nick; Christoffersen, Henrik;

    2014-01-01

    measurements and subjective assessments; here, we also investigate behavioral indicators such as fixation and pupillary dilation. We use such indicators to explore diagram understanding- and reading strategies and how such strategies are impacted, e.g. by diagram type and expertise level. In the pilot eye...

  20. How Young Children View Mathematical Representations: A Study Using Eye-Tracking Technology

    Science.gov (United States)

    Bolden, David; Barmby, Patrick; Raine, Stephanie; Gardner, Matthew

    2015-01-01

    Background: It has been shown that mathematical representations can aid children's understanding of mathematical concepts but that children can sometimes have difficulty in interpreting them correctly. New advances in eye-tracking technology can help in this respect because it allows data to be gathered concerning children's focus of attention and…

  1. Clinical study on the metastasis to the eyes from breast cancer.

    Science.gov (United States)

    Tamura, Miki; Tada, Takashi; Tsuji, Hideki; Tamura, Megumi; Yoshimoto, Masataka; Takahashi, Kaoru; Tada, Keiichiro; Tanabe, Masahiko; Kutomi, Goro; Sekine, Yasuko; Kasumi, Fujio

    2004-01-01

    In our hospital, 24 patients who underwent surgery for breast cancer during 1980 to 2001 were diagnosed with metastasis to the eye. Metastasis to the choroid was found most frequently, making the choroid the most common site of metastasis. A few patients had metastasis to the orbit. Decreased visual acuity and tunnel vision were frequently found in patients who had metastasis to the choroid, and ocular floaters and blurred vision were also found in a few patients. Patients with metastasis to the orbit showed diplopia caused by ocular dyskinesia and eyelid swelling. The mean postoperative period until the diagnosis with metastasis to the eye was 3 years and 2 months, with most cases diagnosed between 20 and 40 months postoperatively, a relatively long period. We performed radiotherapy in 21 of the 24 patients, and more than half of the patients showed improvement. The mean survival period after diagnosis with metastasis to the eye was 10 months, and some of them already had recurrence to other organs such as the bones or lungs. Examination with consideration of metastasis to the eyes is required to improve the quality of life of cancer patients,.

  2. Effects of Saccadic Bilateral Eye Movements on Memory in Children and Adults: An Exploratory Study

    Science.gov (United States)

    Parker, Andrew; Dagnall, Neil

    2012-01-01

    The effects of saccadic bilateral (horizontal) eye movements on true and false memory in adults and children were investigated. Both adults and children encoded lists of associated words in the Deese-Roediger-McDermott paradigm followed by a test of recognition memory. Just prior to retrieval, participants were asked to engage in 30 s of bilateral…

  3. Hidden Communicative Competence: Case Study Evidence Using Eye-Tracking and Video Analysis

    Science.gov (United States)

    Grayson, Andrew; Emerson, Anne; Howard-Jones, Patricia; O'Neil, Lynne

    2012-01-01

    A facilitated communication (FC) user with an autism spectrum disorder produced sophisticated texts by pointing, with physical support, to letters on a letterboard while their eyes were tracked and while their pointing movements were video recorded. This FC user has virtually no independent means of expression, and is held to have no literacy…

  4. Prevalence of age-related maculopathy in older Europeans: The European Eye Study (EUREYE)

    NARCIS (Netherlands)

    C. Augood (Cristina); J.R. Vingerling (Hans); P.T.V.M. de Jong (Paulus); U. Chakravarthy (Usha); J.H. Seland (Johan ); G. Soubrane; L. Tomazzoli (Laura); F. Topouzis (Fotis); G.C. Bentham (Graham ); M. Rahu; J. Vioque (Jesus); I.S. Young (Ian ); A.E. Fletcher (Astrid E.)

    2006-01-01

    textabstractObjective: To estimate the prevalence of age-related maculopathy in an older population from 7 European countries. Methods: Randomly sampled people 65 years and older were invited to an eye examination in centers across 7 European countries (Norway, Estonia, United Kingdom, France, Italy

  5. The Effect of Autologous Platelet Lysate Eye Drops: An In Vivo Confocal Microscopy Study

    Science.gov (United States)

    Fea, Antonio M.; Testa, Valeria; Machetta, Federica; Parisi, Simone; D'Antico, Sergio; Spinetta, Roberta; Fusaro, Enrico; Grignolo, Federico M.

    2016-01-01

    Purpose. To determine the effectiveness of autologous platelet lysate (APL) eye drops in patients with primary Sjögren syndrome (SS) dry eye, refractory to standard therapy, in comparison with patients treated with artificial tears. We focused on the effect of APL on cornea morphology with the in vivo confocal microscopy (IVCM). Methods. Patients were assigned to two groups: group A used autologous platelet lysate QID, and group B used preservative-free artificial tears QID, for 90 days. Ophthalmological assessments included ocular surface disease index (OSDI), best corrected visual acuity (BCVA), Schirmer test, fluorescein score, and breakup time (BUT). A subgroup of patients in group A underwent IVCM: corneal basal epithelium, subbasal nerves, Langerhans cells, anterior stroma activated keratocytes, and reflectivity were evaluated. Results. 60 eyes of 30 patients were enrolled; in group A (n = 20 patients) mean OSDI, fluorescein score, and BUT showed significant improvement compared with group B (n = 10 patients). The IVCM showed a significant increase in basal epithelium cells density and subbasal nerve plexus density and number and a decrease in Langerhans cells density (p < 0.05). Conclusion. APL was found effective in the treatment of SS dry eye. IVCM seems to be a useful tool to visualize cornea morphologic modifications. PMID:27200376

  6. Structural brain MRI studies in eye diseases : are they clinically relevant? A review of current findings

    NARCIS (Netherlands)

    Prins, Doety; Hanekamp, Sandra; Cornelissen, Frans W.

    2016-01-01

    Many eye diseases reduce visual acuity or are associated with visual field defects. Because of the well-defined retinotopic organization of the connections of the visual pathways, this may affect specific parts of the visual pathways and cortex, as a result of either deprivation or transsynaptic deg

  7. The Study of Retinal Nerve Fiber Layer Thickness of Normal Eyes Using Scanning Laser Polarimetry

    Institute of Scientific and Technical Information of China (English)

    Xing Liu; Jingjing Huang; Jian Ge; Yunlan Ling; Xiaoping Zheng

    2006-01-01

    Purpoe: To evaluate retinal nerve fiber layer (RNFL) thickness measurements in local normal Chinese subjects of different age groups and analyse the correlation of RNFL thickness with age using scanning laser polarimetry (SLP, GDxVCC). To assess the reproducibility of RNFL thickness measurement with GDxVCC.Methods: The RNFL thickness of 67 normal subjects (123 eyes) were measured by GDxVCC. The average TSNIT parameters were calculated. The differences of RNFL thickness between sex, right and left eyes, superior and inferior were compared. The relationship between RNFL thickness and age was analyzed with correlation analysis and linear regression analysis. The intraclass correlation coefficients (ICC) of three images in every eye were calculated.Results: The average peripapillary RNFL thickness at the superior, inferior and whole ellipse regions in 123 eyes of 67 normal subjects were (70.30±6.76)μm, (67.35±6.77) μm and (56.87±4.53) μm, respectively. The average TNSIT standard deviation was 23.68±4.61 and the average inter-eye symmetric value was 0.86±0.11. There were significant difference of RNFL thickness between superior and inferior (t=4.952,P <0.001 ). There were significant difference of inferior RNFL thickness and TNSIT standard deviation between right and left eyes (P=0.005 and 0.002),while not significant difference of superior RNFL thickness and whole mean RNFL thickness between right and left eye (P=0.086 and 0.529). There was no significant difference in TSNIT parameters between different genders. There was a slight negative correlation average RNFL thickness in superior sector with age (decreased approximately 0.15 microns per year,P=0.047) in the subjects aged below 60 years old. The ICC values of RNFL thickness were >0.8 in superior, inferior and global.Conclusions: The RNFL thickness can be measured accurately by GDxVCC and the reproducibility of RNFL thickness measurement by GDxVCC is good. There was a slight negative correlation between

  8. Observing Third-Party Attentional Relationships Affects Infants' Gaze Following: An Eye-Tracking Study

    Science.gov (United States)

    Meng, Xianwei; Uto, Yusuke; Hashiya, Kazuhide

    2017-01-01

    Not only responding to direct social actions toward themselves, infants also pay attention to relevant information from third-party interactions. However, it is unclear whether and how infants recognize the structure of these interactions. The current study aimed to investigate how infants' observation of third-party attentional relationships influence their subsequent gaze following. Nine-month-old, 1-year-old, and 1.5-year-old infants (N = 72, 37 girls) observed video clips in which a female actor gazed at one of two toys after she and her partner either silently faced each other (face-to-face condition) or looked in opposite directions (back-to-back condition). An eye tracker was used to record the infants' looking behavior (e.g., looking time, looking frequency). The analyses revealed that younger infants followed the actor's gaze toward the target object in both conditions, but this was not the case for the 1.5-year-old infants in the back-to-back condition. Furthermore, we found that infants' gaze following could be negatively predicted by their expectation of the partner's response to the actor's head turn (i.e., they shift their gaze toward the partner immediately after they realize that the actor's head will turn). These findings suggested that the sensitivity to the difference in knowledge and attentional states in the second year of human life could be extended to third-party interactions, even without any direct involvement in the situation. Additionally, a spontaneous concern with the epistemic gap between self and other, as well as between others, develops by this age. These processes might be considered part of the fundamental basis for human communication.

  9. Linkage analysis of quantitative refraction and refractive errors in the Beaver Dam Eye Study.

    Science.gov (United States)

    Klein, Alison P; Duggal, Priya; Lee, Kristine E; Cheng, Ching-Yu; Klein, Ronald; Bailey-Wilson, Joan E; Klein, Barbara E K

    2011-07-13

    Refraction, as measured by spherical equivalent, is the need for an external lens to focus images on the retina. While genetic factors play an important role in the development of refractive errors, few susceptibility genes have been identified. However, several regions of linkage have been reported for myopia (2q, 4q, 7q, 12q, 17q, 18p, 22q, and Xq) and for quantitative refraction (1p, 3q, 4q, 7p, 8p, and 11p). To replicate previously identified linkage peaks and to identify novel loci that influence quantitative refraction and refractive errors, linkage analysis of spherical equivalent, myopia, and hyperopia in the Beaver Dam Eye Study was performed. Nonparametric, sibling-pair, genome-wide linkage analyses of refraction (spherical equivalent adjusted for age, education, and nuclear sclerosis), myopia and hyperopia in 834 sibling pairs within 486 extended pedigrees were performed. Suggestive evidence of linkage was found for hyperopia on chromosome 3, region q26 (empiric P = 5.34 × 10(-4)), a region that had shown significant genome-wide evidence of linkage to refraction and some evidence of linkage to hyperopia. In addition, the analysis replicated previously reported genome-wide significant linkages to 22q11 of adjusted refraction and myopia (empiric P = 4.43 × 10(-3) and 1.48 × 10(-3), respectively) and to 7p15 of refraction (empiric P = 9.43 × 10(-4)). Evidence was also found of linkage to refraction on 7q36 (empiric P = 2.32 × 10(-3)), a region previously linked to high myopia. The findings provide further evidence that genes controlling refractive errors are located on 3q26, 7p15, 7p36, and 22q11.

  10. Color vision deficiency in a middle-aged population: the Shahroud Eye Study.

    Science.gov (United States)

    Jafarzadehpur, Ebrahim; Hashemi, Hassan; Emamian, Mohammad Hassan; Khabazkhoob, Mehdi; Mehravaran, Shiva; Shariati, Mohammad; Fotouhi, Akbar

    2014-10-01

    The aim of this study was to determine the prevalence of color vision defects in the middle-age population of Shahroud, Iran. We selected 6,311 people from the 40- to 64-year-old population through random cluster sampling. Color vision testing was performed with the Farnsworth D-15. Cases with similar and symmetric results in both eyes were classified as hereditary, and those with asymmetric results were considered acquired. Cases that did not conform to standard patterns were classified as unknown category. Of 5,190 respondents (response rate 82.2 %), 5,102 participants underwent the color vision test. Of these, 14.7 % (95 % confidence interval 13.7-15.6) had some type of color vision deficiency. Of the 2,157 male participants, 6.2 % were hereditary and 10.2 % were acquired and of the 2,945 female participants, 3.1 % were hereditary and 10 % were acquired. Hereditary color deficiencies were mostly of the deutan form (63.8 %), and acquired deficiencies were mostly tritan (66.1 %). The prevalence of hereditary and acquired color vision deficiency, as well as different types of red-green and blue-yellow color vision defects significantly increased with age (p color vision defects among the middle-aged population of Shahroud was significantly different from that seen in the younger population. This could be due to changes associated with age, gender, medical and ocular conditions, and differences in race and environment. Thus, results of previous examinations and the overall health status should be considered before making any judgment about the status of color vision in middle-aged people.

  11. Are smooth pursuit eye movements altered in chronic whiplash-associated disorders? A cross-sectional study

    DEFF Research Database (Denmark)

    Kongsted, Alice; Jørgensen, L V; Bendix, T

    2007-01-01

    To evaluate whether smooth pursuit eye movements differed between patients with long-lasting whiplash-associated disorders and controls when using a purely computerized method for the eye movement analysis.......To evaluate whether smooth pursuit eye movements differed between patients with long-lasting whiplash-associated disorders and controls when using a purely computerized method for the eye movement analysis....

  12. Corneal refractive power and its associations with ocular and general parameters: the Central India Eye and Medical Study.

    Science.gov (United States)

    Jonas, Jost B; Nangia, Vinay; Sinha, Ajit; Gupta, Rajesh

    2011-09-01

    To investigate the normal distribution of corneal refractive power (CRP) and its associations with other ocular and systemic parameters in the Central Indian population. Population-based study. The Central India Eye and Medical Study is a population-based study performed in a rural region of Central India. The study comprised 4711 subjects aged 30+ years. A detailed ophthalmic and medical examination was performed. Horizontal and vertical CRP were measured using a non-automatic keratometer. Corneal refractive power. After excluding pseudophakic or aphakic eyes, keratometric measurements were available on 9024 eyes of 4617 study participants (98.0%) with a mean age of 49.1±13.2 years (range, 30-100 years) and a mean refractive error of -0.20±1.52 diopters (D). Mean horizontal CRP was 44.60±1.68 D (mean ± standard deviation; range, 36.5-52.0 D), and vertical CRP was 44.62±1.74 D (range, 37.75-52.0 D) with no significant difference between both parameters (P=0.27). In multivariate analysis, CRP was significantly (P eyes with CRP ≥48 D were excluded. Horizontal CRP increased with higher age, lower level of education, lower body height, thinner central cornea, deeper anterior chamber, shorter axial length, and myopic refractive error. The association with age may be of importance for refractive surgery. The association of a steeper cornea with a shorter body stature and a shorter axial length parallels an association between shorter body length and shorter axial length without association with refractive error. The association among steeper cornea, shorter body length, and lower educational level complements the association between shorter body length and lower educational level. The correlation between steeper cornea and deeper anterior chamber may be explained geometrically. Copyright © 2011 American Academy of Ophthalmology. Published by Elsevier Inc. All rights reserved.

  13. Unilateral Amblyopia Affects Two Eyes: Fellow Eye Deficits in Amblyopia.

    Science.gov (United States)

    Meier, Kimberly; Giaschi, Deborah

    2017-03-01

    Unilateral amblyopia is a visual disorder that arises after selective disruption of visual input to one eye during critical periods of development. In the clinic, amblyopia is understood as poor visual acuity in an eye that was deprived of pattern vision early in life. By its nature, however, amblyopia has an adverse effect on the development of a binocular visual system and the interactions between signals from two eyes. Visual functions aside from visual acuity are impacted, and many studies have indicated compromised sensitivity in the fellow eye even though it demonstrates normal visual acuity. While these fellow eye deficits have been noted, no overarching theory has been proposed to describe why and under what conditions the fellow eye is impacted by amblyopia. Here, we consider four explanations that may account for decreased fellow eye sensitivity: the fellow eye is adversely impacted by treatment for amblyopia; the maturation of the fellow eye is delayed by amblyopia; fellow eye sensitivity is impacted for visual functions that rely on binocular cortex; and fellow eye deficits reflect an adaptive mechanism that works to equalize the sensitivity of the two eyes. To evaluate these ideas, we describe five visual functions that are commonly reported to be deficient in the amblyopic eye (hyperacuity, contrast sensitivity, spatial integration, global motion, and motion-defined form), and unify the current evidence for fellow eye deficits. Further research targeted at exploring fellow eye deficits in amblyopia will provide us with a broader understanding of normal visual development and how amblyopia impacts the developing visual system.

  14. Intraocular pressure and associations in children. The Gobi Desert Children Eye Study.

    Directory of Open Access Journals (Sweden)

    Da Yong Yang

    Full Text Available PURPOSE: To assess the intraocular pressure (IOP and its association in children in a population living in an oasis in the Gobi Desert. METHODS: The cross-sectional school-based study included all schools in the Ejina region. The children underwent an ophthalmic examination, non-contact tonometry and measurement of blood pressure and body height and weight. RESULTS: Out of eligible 1911 children, 1565 (81.9% children with a mean age of 11.9±3.5 years (range: 6-21 years participated. Mean spherical refractive error was -1.58±2.00 diopters. In multivariate analysis, higher IOP (right eye was associated with younger age (P<0.001; standardized coefficient beta: -0.13; regression coefficient B: -0.13; 95% Confidence interval (CI:-0.18, -0.07, higher diastolic blood pressure (P<0.001;beta:0.13;B:0.05;95%CI:0.03,0.07, higher corneal refractive power (P<0.001;beta:0.11;B:0.23;95%CI:0.12,0.34, more myopic refractive error (P = 0.035;beta: -0.06;B: -0.10;95%CI: -0.19, -0.001, and Han Chinese ethnicity of the father (P = 0.03;beta:0.06;B:0.42;95%CI:0.04,0.89. If age and diastolic blood pressure were dropped, higher IOP was associated with higher estimated cerebrospinal fluid pressure (CSFP (P<0.001;beta:0.09; B:0.13;95%CI:0.06,0.21 after adjusting for higher corneal refractive power (P<0.001 and Han Chinese ethnicity of the father (P = 0.04. Correspondingly, higher IOP of the left eye was associated with younger age (P<0.001;beta: -0.15;B: -0.16;95%CI: -0.21, -0.10, female gender (P<0.001;beta:0.09;B:0.65;95%CI:0.30,1.01, higher corneal refractive power (P<0.001;beta:0.08;B:0.19;95%CI:0.06,0.32, more myopic refractive error (P = 0.03;beta: -0.06;B: -0.12;95%CI: -0.22, -0.01, and higher estimated CSFP (P<0.001;beta:0.11;B:0.17;95%CI:0.09,0.24. CONCLUSIONS: In school children, higher IOP was associated with steeper corneal curvature and with younger age and higher blood pressure, or alternatively, with higher estimated CSFP. Corneal

  15. Qualitative study on the awareness of eye health risks associated with type II diabetes in Lagos, Nigeria

    OpenAIRE

    Umaefulam, Valerie Onyinyechi

    2015-01-01

    Introduction: Diabetes mellitus is a major public health problem and its burden is expected to increase in developing countries such as Nigeria. One of the most frequent complications of type II diabetes is diabetic retinopathy, and a major cause of blindness worldwide especially among adults. Objective: To determine the awareness of diabetes – related eye health risks and complications among type II diabetics in Lagos, Nigeria. Method: The study was carried out in Rhowil Medical Centre in La...

  16. Pneumatic retinopexy: the evolution of case selection and surgical technique. A twelve-year study of 302 eyes.

    OpenAIRE

    Tornambe, P E

    1997-01-01

    BACKGROUND: Pneumatic retinopexy is an operation for reattaching the retina by injecting an expanding gas bubble and using laser and/or cryopexy. The procedure is controversial because the literature reports a variable initial success rate, sometimes less than conventional scleral buckling surgery. PR is done in an office setting and may be the most cost-effective means of retinal reattachment. OBJECTIVE: The goal of this study is to decide which eyes are most successfully treated with pneuma...

  17. Apply Web-based Analytic Tool and Eye Tracking to Study The Consumer Preferences of DSLR Cameras

    OpenAIRE

    Jih-Syongh Lin; Shih-Yen Huang

    2013-01-01

    Consumer’s preferences and purchase motivation of products often lie in the purchasing behaviors generated by the synthetic evaluation of form features, color, function, and price of products. If an enterprise can bring these criteria under control, they can grasp the opportunities in the market place. In this study, the product form, brand, and prices of five DSLR digital cameras of Nikon, Lumix, Pentax, Sony, and Olympus were investigated from the image evaluation and eye tracking. The web-...

  18. A clinical comparison between DisCoVisc and 2% hydroxypropylmethylcellulose in phacoemulsification: a fellow eye study

    OpenAIRE

    Espíndola, Rodrigo F.; Castro, Emerson F.S.; Marcony R. Santhiago; Newton Kara-Junior

    2012-01-01

    OBJECTIVE: This study sought to compare the effects and outcomes of two ophthalmic viscosurgical devices, 1.6% hyaluronic acid/4.0% chondroitin sulfate and 2.0% hydroxypropylmethylcellulose, during phacoemulsification. METHODS: This prospective, randomized clinical trial comprised 78 eyes (39 patients) that received phacoemulsification performed by the same surgeon using a standardized technique. Patients were randomly assigned to receive either 1.6% hyaluronic acid/4.0% chondroitin sulfate o...

  19. Association of common SIX6 polymorphisms with peripapillary retinal nerve fiber layer thickness: the Singapore Chinese Eye Study.

    Science.gov (United States)

    Cheng, Ching-Yu; Allingham, R Rand; Aung, Tin; Tham, Yih-Chung; Hauser, Michael A; Vithana, Eranga N; Khor, Chiea Chuen; Wong, Tien Yin

    2014-12-23

    Recently the common SIX6 missense variant rs33912345 was found to be highly associated with glaucoma. The aim of this study was to investigate the association between this SIX6 variant and peripapillary retinal nerve fiber layer (RNFL) thickness measured by spectral-domain optical coherence tomography (SD-OCT) in a population setting. Study subjects were enrolled from the Singapore Chinese Eye Study (SCES), a population-based survey of Singaporean Chinese aged 40 years or older. Subjects underwent a comprehensive ocular examination. Spectral-domain OCT was used to measure RNFL thicknesses. Genotyping of SIX6 rs33912345 (Asn141His) was performed using HumanExome BeadChip. A total of 2129 eyes from 1243 SCES subjects (mean age: 55.0 ± 7.4 years) with rs33912345 genotype data and SD-OCT images were included for the analysis. Of these, 26 eyes of 21 subjects had glaucoma. The frequency of rs33912345 risk variant C (His141) was 80% in the study subjects. Each rs33912345 C allele was associated with a decrease of 1.44 μm in RNFL thickness after adjusting for age, sex, genetic principal components, and axial length (P = 0.001). These associations remained similar in 2096 nonglaucoma eyes in which each C allele was associated with a decrease of 1.39 μm in RNFL thickness (P = 0.001). The strongest association was observed in the superior RNFL sector (a decrease of 2.83 μm per risk allele, P regions known to be particularly affected in those with glaucoma. This may be the primary mechanism for increased risk of POAG in individuals who carry the SIX6 His141 risk variant. Copyright 2015 The Association for Research in Vision and Ophthalmology, Inc.

  20. Child attention to pain and pain tolerance are dependent upon anxiety and attention control: An eye-tracking study.

    Science.gov (United States)

    Heathcote, L C; Lau, J Y F; Mueller, S C; Eccleston, C; Fox, E; Bosmans, M; Vervoort, T

    2017-02-01

    Pain is common and can be debilitating in childhood. Theoretical models propose that attention to pain plays a key role in pain outcomes, however, very little research has investigated this in youth. This study examined how anxiety-related variables and attention control interacted to predict children's attention to pain cues using eye-tracking methodology, and their pain tolerance on the cold pressor test (CPT). Children aged 8-17 years had their eye-gaze tracked whilst they viewed photographs of other children displaying painful facial expressions during the CPT, before completing the CPT themselves. Children also completed self-report measures of anxiety and attention control. Findings indicated that anxiety and attention control did not impact children's initial fixations on pain or neutral faces, but did impact how long they dwelled on pain versus neutral faces. For children reporting low levels of attention control, higher anxiety was associated with less dwell time on pain faces as opposed to neutral faces, and the opposite pattern was observed for children with high attention control. Anxiety and attention control also interacted to predict pain outcomes. For children with low attention control, increasing anxiety was associated with anticipating more pain and tolerating pain for less time. This is the first study to examine children's attention to pain cues using eye-tracking technology in the context of a salient painful experience. Data suggest that attention control is an important moderator of anxiety on multiple outcomes relevant to young people's pain experiences. This study uses eye tracking to study attention to pain cues in children. Attention control is an important moderator of anxiety on attention bias to pain and tolerance of cold pressor pain in youth. © 2016 European Pain Federation - EFIC®.

  1. Researching the cognitive validity of GEPT High-Intermediate and Advanced Reading: an eye tracking and stimulated recall study

    OpenAIRE

    2016-01-01

    It is important for any language test to establish its cognitive validity in order to ensure that the test elicits from test takers those cognitive processes which correspond to the processes which they would normally employ in the target real-life context (Weir 2005). This study investigates the cognitive validity of the GEPT Reading Test at two levels. High-intermediate (CEFR B2) and Advanced (CEFR C1), using innovative eye-tracking technology and detailed stimulated recall interviews and s...

  2. Genetic mechanisms involved in the evolution of the cephalopod camera eye revealed by transcriptomic and developmental studies

    OpenAIRE

    Ogura Atsushi; Yoshida Masa-aki

    2011-01-01

    Abstract Background Coleoid cephalopods (squids and octopuses) have evolved a camera eye, the structure of which is very similar to that found in vertebrates and which is considered a classic example of convergent evolution. Other molluscs, however, possess mirror, pin-hole, or compound eyes, all of which differ from the camera eye in the degree of complexity of the eye structures and neurons participating in the visual circuit. Therefore, genes expressed in the cephalopod eye after divergenc...

  3. Influence on ocular surface after cataract surgery and effect of topical diquafosol on postoperative dry eye: a multicenter prospective randomized study

    Directory of Open Access Journals (Sweden)

    Miyake K

    2017-03-01

    Full Text Available Kensaku Miyake,1 Norihiko Yokoi2 On behalf of Dry Eye After Cataract Surgery Investigational Study Group (DASIS group 1Miyake Eye Hospital, Nagoya, 2Department of Ophthalmology, Kyoto Prefectural University of Medicine, Kyoto, Japan Purpose: To investigate influences of 3% diquafosol sodium ophthalmic solution (DQS on ocular surface after cataract surgery and effects on postoperative dry eye. Design: This study had two consecutive prospective study phases. The former was an observational study from before cataract surgery to 4 weeks after surgery and the latter was a randomized open-label study from 4 to 8 weeks after surgery. Methods: Subjects were 433 eyes of 433 patients undergoing cataract surgery with intraocular lens implantation. Dry eye examination of tear breakup time (BUT, corneal and conjunctival fluorescein staining scores, total subjective symptom score (12 symptoms, and Schirmer I test were conducted before surgery and 4 weeks after surgery. Patient demographics and these examination results were used to analyze risk factors to predict postoperative dry eye. In a randomized study, 154 eyes diagnosed with dry eye postoperatively were applied either DQS or artificial tears (AT six times daily for 4 weeks. The data of the examinations were compared. Results: At 4 weeks after surgery, BUT was shortened significantly (P=0.036, fluorescein staining score increased significantly (P=0.012, but total subjective symptom score was significantly improved (P<0.001. The majority of postoperative dry eye was shortened BUT type (53.1%. The dry eye prevalence after surgery decreased (55.7% compared with before surgery (69.7%. Females and the patient with dry eye symptoms before surgery had significant risk factors for postoperative dry eye. In a randomized study, BUT was significantly prolonged in the DQS group (P=0.015, but not in the AT group. Fluorescein staining score was significantly improved in both groups (P<0.001. Total subjective symptom

  4. A NEW DISCRETE HARTLEY TRANSFORM PRECODING BASED INTERLEAVED-OFDMA UPLINK SYSTEM WITH REDUCED PAPR FOR 4G CELLULAR NETWORKS

    Directory of Open Access Journals (Sweden)

    VARUN JEOTI

    2011-12-01

    Full Text Available High peak-to-average power ratio (PAPR reduction is one of the major challenges in orthogonal frequency division multiple access (OFDMA systems since last decades. High PAPR increases the complexity of analogue-to-digital (A/D and digital-to-analogue (D/A convertors and also reduces the efficiency of RF high-power-amplifier (HPA. In this paper, we present a new Discrete- Hartley transform (DHT precoding based interleaved-OFDMA uplink system for PAPR reduction in the upcoming 4G cellular networks. Extensive computer simulations have been performed to analyze the PAPR of the proposed system with root-raised-cosine (RRC pulse shaping. We also compare simulation results of the proposed system with the conventional interleaved-OFDMA uplink systems and the Walsh-Hadamard transform (WHT precoding based interleaved-OFDMA uplink systems. It is concluded from the computer simulations that the proposed system has low PAPR as compared to the conventional interleaved-OFDMA uplink systems and the WHT precoded interleaved-OFDMA uplink systems.

  5. Temporal and Spatial Aspects of Gas Release During the 2010 Apparition of Comet 103P/Hartley-2

    CERN Document Server

    Mumma, M J; Villanueva, G L; Paganini, L; DiSanti, M A; Gibb, E L; Keane, J V; Meech, K J; Blake, G A; Ellis, R S; Lippi, M; Bõhnhardt, H; Magee-Sauer, K

    2011-01-01

    We report measurements of eight primary volatiles (H2O, HCN, CH4, C2H6, CH3OH, C2H2, H2CO, and NH3) and two product species (OH and NH2) in comet 103P/Hartley-2 using high dispersion infrared spectroscopy. We quantified the long- and short-term behavior of volatile release over a three-month interval that encompassed the comet's close approach to Earth, its perihelion passage, and flyby of the comet by the Deep Impact spacecraft during the EPOXI mission. We present production rates for individual species, their mixing ratios relative to water, and their spatial distributions in the coma on multiple dates. The production rates for water, ethane, HCN, and methanol vary in a manner consistent with independent measures of nucleus rotation, but mixing ratios for HCN, C2H6, & CH3OH are independent of rotational phase. Our results demonstrate that the ensemble average composition of gas released from the nucleus is well defined, and relatively constant over the three-month interval (September 18 through December...

  6. The Highly Unusual Outgassing of Comet 103P/Hartley 2 from Narrowband Photometry and Imaging of the Coma

    CERN Document Server

    Knight, Matthew M

    2012-01-01

    We report on photometry and imaging of Comet 103P/Hartley 2 obtained at Lowell Observatory from 1991 through 2011. We acquired photoelectric photometry on two nights in 1991, four nights in 1997/98, and 13 nights in 2010/11. We observed a strong secular decrease in water and all other observed species production in 2010/11 from the 1991 and 1997/98 levels. We see evidence for a strong asymmetry with respect to perihelion in the production rates of our usual bandpasses, with peak production occurring ~10 days post-perihelion and production rates considerably higher post-perihelion. The composition was "typical", in agreement with the findings of other investigators. We obtained imaging on 39 nights from 2010 July until 2011 January. We find that, after accounting for their varying parentage and lifetimes, the C2 and C3 coma morphology resemble the CN morphology we reported previously. These species exhibited an hourglass shape in October and November, and the morphology changed with rotation and evolved over t...

  7. Long term photometric monitoring of comet 103P/Hartley2 with the new robotic TRAPPIST telescope

    Science.gov (United States)

    Jehin, E.; Manfroid, J.; Hutsemékers, D.; Gillon, M.; Magain, P.

    2011-10-01

    We report on a long term monitoring of comet 103P/Hartley2 with six cometary narrow band filters using the TRAPPIST 0.60m telescope installed recently at the ESO La Silla observatory in Chile. This new robotic telescope is dedicated to exoplanet and solar system research. The comet was observed with the cometary filters during 4 months, from Oct. 29 to Feb. 22. Since then the monitoring continues but only through the BVRI filters and about two times per week. Those observations allowed us to make a detailed light curve of the comet after its perihelion passage and derive production rates of the 4 main species (OH, CN, C2, C3) as well as the dust production rate (Afρ) over that period. The high sampling of our monitoring allowed us to find a periodicity in the gaseous light curves and to deduce a rotation period of 18.4h early November, slowing down to about 19h by the end of December.

  8. Gas and dust productions of comet 103P/Hartley 2 from millimetre observations: interpreting rotation-induced time variations

    CERN Document Server

    Boissier, J; Biver, N; Colom, P; Crovisier, J; Moreno, R; Zakharov, V; Groussin, O; Jorda, L; Lis, D C

    2013-01-01

    Comet 103P/Hartley 2 made a close approach to the Earth in October 2010. It was the target of an extensive observing campaign and was visited by the Deep Impact spacecraft (mission EPOXI). We present observations of HCN and CH3OH emission lines conducted with the IRAM Plateau de Bure interferometer on 22-23, 28 October and 4, 5 November 2010 at 1.1, 1.9 and 3.4 mm wavelengths. The thermal emission from the dust coma and nucleus is detected simultaneously. Interferometric images with unprecedented spatial resolution are obtained. A sine-wave variation of the thermal continuum is observed in the 23 October data, that we associate with the nucleus thermal light curve. The nucleus contributes up to 30-55 % of the observed continuum. The large dust-to-gas ratio (in the range 2-6) can be explained by the unusual activity of the comet for its size, which allows decimeter size particles and large boulders to be entrained by the gas. The rotational temperature of CH3OH is measured. We attribute the increase from 35 to...

  9. Association Between Serum 25-Hydroxyvitamin D Levels and Dry Eye in Korean Adults: A Study Based on Korean National Health and Nutrition Examination Survey, 2010–2011

    Science.gov (United States)

    Kim, Min Ji; Kim, Yun-Jin; Lee, Sang-Yeoup; Lee, Jeong-Gyu; Jeong, Dong-Wook; Kim, Yun Hee

    2017-01-01

    Background Dry eye is a common disease. Many patients continue to experience residual symptoms despite optimal treatment. Thus, new treatment options are required. The purpose of this study was to evaluate the association between serum 25-hydroxyvitamin D [25(OH)D] levels and dry eye. Methods This study was performed using data from the fifth Korean National Health and Nutrition Examination Survey, which is a cross-sectional study of the Korean population that was conducted from 2010 to 2011. We included adults aged >19 years who underwent ophthalmologic interviews and examinations. We excluded subjects who had comorbid conditions (rheumatoid arthritis, thyroid disease, chronic kidney disease, or depression) that are associated with dry eye. The subjects were divided into normal and dry eye groups. The dry eye group consisted of those who had clinically diagnosed dry eye syndrome or symptoms. Multiple logistic regression analysis was conducted to determine the association between serum 25(OH)D levels and dry eye. Results In the univariate model, the 25(OH)D levels were lower in the dry eye group than in the normal group (P=0.01). A significant association was found between severe vitamin D deficiency (<10 ng/mL) and dry eye (P=0.04). However, after multivariate adjustment, the statistical significance of the association disappeared (P-values= 0.49, vitamin D insufficiency; P=0.33, vitamin D deficiency; P=0.18, severe vitamin D deficiency). Conclusion Severe vitamin D deficiency was associated with dry eye in an unadjusted model, but the association was not statistically significant after adjustment. PMID:28360983

  10. Ten-year cumulative incidence of diabetic retinopathy. The Beijing Eye Study 2001/2011.

    Directory of Open Access Journals (Sweden)

    Jie Xu

    Full Text Available To assess the cumulative 10-year incidence of diabetic retinopathy (DR and its associated factors in a population living in Greater Beijing.The population-based longitudinal Beijing Eye Study, which included 4439 subjects (age in 2001: 40+years in 2001, was repeated in 2011 with 2695 subjects participating (66.4% of the survivors. The study participants underwent a detailed ophthalmic examination. Fundus photographs were examined for the new development of DR.After excluding individuals with DR at baseline (n = 87 or no sufficient fundus photographs in 2011 (n = 6, the study included 2602 subjects with a mean age of 64.6±9.7 years (median: 64.0 years; range: 50 to 93 years. In the 10-year period, 109 subjects (39 men developed new DR with an incidence of 4.2% (95% confidence interval (CI: 3.45,5.03. In multiple logistic regression analysis, incident DR was significantly associated with higher HbA1c value (P<0.001; Odds Ratio (OR: 1.73; 95% Confidence Interval (CI: 1.35,2.21, longer duration of diabetes mellitus (P<0.001; OR: 1.16; 95% CI: 1.10,1.22, higher serum concentration of creatinine (P = 0.02; OR: 1.01; 95% CI: 1.002,1.022, lower educational level (P = 0.049; OR: 0.74; 95% CI: 0.55,0.99, higher estimated cerebrospinal fluid pressure (P = 0.038; OR: 1.10; 95% CI: 1.01,1.22, and shorter axial length (P<0.001; OR: 0.48; 95% CI: 0.33,0.71.The cumulative 10-year incidence (mean: 4.2% of DR in a North Chinese population was significantly associated with a higher HbA1c value, longer known duration of diabetes mellitus, higher estimated CSFP and shorter axial length (P<0.001. Shorter axial length (or hyperopia and, potentially, higher CSFP may be additional risk factors to be taken into account when counseling and treating patients with diabetes mellitus.

  11. Spreading of hemiretinal projections in the ipsilateral tectum following unilateral enucleation: a study of optic nerve regeneration in Xenopus with one compound eye.

    Science.gov (United States)

    Straznicky, C; Tay, D

    1981-02-01

    Right compound eyes were formed in Xenopus embryos at stages 32-33 by the fusion of two nasal (NN), two ventral (VV) or two temporal (TT) halves. Shortly after metamorphosis the optic nerve from the compound eye was sectioned and the left intact eye removed. The retinotectal projections from the compound eye to the contralateral and ipsilateral tecta were studied by [3H]proline autoradiography and electrophysiological mapping between 6 weeks and 5 months after the postmetamorphic surgery. The results showed that NN and VV eyes projected to the entire extent of both tecta. In contrast, optic fibre projection from TT eyes, although more extensive than the normal temporal hemiretinal projection, failed to cover the caudomedial portion of the tecta. The visuotectal projections in all three combinations corresponded to typical reduplicated maps to be expected from such compound eyes, where each of the hemiretinae projected across the contralateral and ipsilateral tecta in an overlapping fashion. The rapid expansion of the hemiretinal projections of the compound eyes in the ipsilateral tectum following the removal of the resident optic fibre projection suggests that tectal markers may be carried and deployed by the incoming optic fibres themselves.

  12. The influences of working memory representations on long-range regression in text reading: An eye-tracking study

    Directory of Open Access Journals (Sweden)

    Teppei eTanaka

    2014-09-01

    Full Text Available The present study investigated the relationship between verbal and visuospatial working memory capacity and long-range regression (i.e., word relocation processes in reading. We analyzed eye movements during a whodunit task, in which readers were asked to answer a content question while original text was being presented. The eye movements were more efficient in relocating a target word when the target was at recency positions within the text than when it was at primacy positions. Furthermore, both verbal and visuospatial working memory capacity partly predicted the efficiency of the initial long-range regression. The results indicate that working memory representations have a strong influence at the first stage of long-range regression by driving the first saccade movement toward the correct target position, suggesting that there is a dynamic interaction between internal working memory representations and external actions during text reading.

  13. Selenium Preferentially Accumulates in the Eye Lens Following Embryonic Exposure: A Confocal X-ray Fluorescence Imaging Study

    Energy Technology Data Exchange (ETDEWEB)

    Choudhury, Sanjukta; Thomas, Jith; Sylvain, Nicole J.; Ponomarenko, Olena; Gordon, Robert A.; Heald, Steve M.; Janz, David M.; Krone, Patrick H.; Coulthard, Ian; George, Graham N.; Pickering, Ingrid J.

    2015-02-17

    Maternal transfer of elevated selenium (Se) to offspring is an important route of Se exposure for fish in the natural environment. However, there is a lack of information on the tissue specific spatial distribution and speciation of Se in the early developmental stages of fish, which provide important information about Se toxicokinetics. The effect of maternal transfer of Se was studied by feeding adult zebrafish a Se-elevated or a control diet followed by collection of larvae from both groups. Novel confocal synchrotron-based techniques were used to investigate Se within intact preserved larvae. Confocal X-ray fluorescence imaging was used to compare Se distributions within specific planes of an intact larva from each of the two groups. The elevated Se treatment showed substantially higher Se levels than the control; Se preferentially accumulated to highest levels in the eye lens, with lower levels in the retina, yolk and other tissues. Confocal X-ray absorption spectroscopy was used to determine that the speciation of Se within the eye lens of the intact larva was a selenomethionine-like species. Preferential accumulation of Se in the eye lens may suggest a direct cause-and-effect relationship between exposure to elevated Se and Se-induced ocular impairments reported previously. This study illustrates the effectiveness of confocal X-ray fluorescence methods for investigating trace element distribution and speciation in intact biological specimens

  14. Psychophysiological Responsivity to Script-Driven Imagery: An Exploratory Study of the Effects of Eye Movements on Public Speaking Flashforwards.

    Science.gov (United States)

    Kearns, Michelle; Engelhard, Iris M

    2015-01-01

    A principle characteristic of public speaking anxiety relates to intrusive mental images of potential future disasters. Previous research has found that the self-reported emotionality of such "flashforwards" can be reduced by a cognitively demanding, dual-task (e.g., making eye movements) performed whilst holding the mental image in-mind. The outcome measure in these earlier studies was participants' self-reported emotional intensity of the mental image. The current study (N = 34) explored whether an objective measure of emotionality would yield similar results in students with public speaking anxiety. A script-driven imagery procedure was used to measure psychophysiological responsivity to an audio script depicting a feared (public speaking) scenario before and after an eye movement intervention. Relative to the control condition (imagery only), those who made eye movements whilst holding a mental image of this scenario in-mind demonstrated a significant decrease in heart rate, which acted as a measure of emotionality. These findings add to a previous body of research demonstrating the beneficial qualities of dual-tasks and their potential for treatment of both past and future-oriented anxieties.

  15. Qualitative study on the awareness of eye health risks associated with type II diabetes in Lagos, Nigeria

    Directory of Open Access Journals (Sweden)

    Valerie Onyinyechi Umaefulam

    2015-12-01

    Full Text Available Introduction: Diabetes mellitus is a major public health problem and its burden is expected to increase in developing countries such as Nigeria. One of the most frequent complications of type II diabetes is diabetic retinopathy, and a major cause of blindness worldwide especially among adults. Objective: To determine the awareness of diabetes – related eye health risks and complications among type II diabetics in Lagos, Nigeria. Method: The study was carried out in Rhowil Medical Centre in Lagos, Nigeria and adopted qualitative methodology. Data was collected via semi-structured interviews. Interviews were carried out on nine type II diabetes patients above the age of eighteen via purposive sampling. The interviews were analyzed based on Kvale’s framework for the qualitative data analysis. Results: Knowledge of diabetes, sources of information, cultural health beliefs and practices, and communication were themes that emerged from the thematic analysis. The data revealed significant gaps in awareness of diabetes-related eye complications amongst type II diabetics. Data showed poor knowledge of diabetes-related eye diseases and of inadequate awareness of the connection between diabetes and ocular complications. Also, education, health literacy and communication barrier problems between health professionals and diabetic patients were also evident. In addition, sources of information on diabetes and eye care, as well as health beliefs influenced awareness. Conclusion: Findings from this study can inform strategic plans of public health authorities in addressing the growing diabetes epidemic by developing effective health education programs with the aim to increase awareness amongst people living with diabetes in the region.

  16. STUDY OF CORRELATION AND SIGNIFICANCE OF BIOCHEMICAL PARAMETERS IN THE ASSESSMENT OF ACTIVE PHASE OF THYROID EYE DISEASE

    Directory of Open Access Journals (Sweden)

    Ashok Kumar P

    2016-08-01

    Full Text Available AIM Role of Interleukin-6 and HS-CRP Levels in the assessment of active thyroid eye disease. MATERIALS & METHODS A prospective observational study of 30 patients from the age group of 20-60 years with thyroid eye disease done at Regional Institute of Ophthalmology. All patients were subjected to detailed history, ocular examination, systemic examination, biochemical analysis and Imaging. Patients are categorised as mild, moderate and severe active disease based on clinical activity score. For the period of two years, patients are followed at regular periodic intervals according to the severity of disease and results were analysed. RESULTS Out of 30 patients studied, majority of the patients were females (60%, and 70% of the patients had bilateral disease. Among 30 patients, 83.33% in hyperthyroid state, 3.33% in Hypothyroid state, 13.33% in Euthyroid state (Table 3. Smoking being important risk factor in 30% among males. 50% of patients presented with mild disease, 30% with moderate disease, 0% with severe disease. IL-6, HS-CRP levels are increased only in patients with severe active disease (Table 6. Remission attained in all patients when treated earlier with steroids. CONCLUSION Identifying disease activity early and aggressive treatment with systemic steroids in active phase of moderate and severe disease has reduced the morbidity associated with disease. Correlation of IL-6, HS-CRP, TFT levels are significantly increased only in patients with active phase of severe thyroid eye disease but not significantly elevated in active phase of moderate disease. Another pitfall is IL-6 is an expensive ELISA based diagnosis. Thus, IL-6 & HS-CRP cannot be routinely used to screen patients with Thyroid eye disease.

  17. Body height, estimated cerebrospinal fluid pressure and open-angle glaucoma. The Beijing Eye Study 2011.

    Directory of Open Access Journals (Sweden)

    Jost B Jonas

    Full Text Available PURPOSE: To examine potential associations between body height, cerebrospinal fluid pressure (CSFP, trans-lamina cribrosa pressure difference (TLCPD and prevalence of open-angle glaucoma (OAG in a population-based setting. METHODS: The population-based Beijing Eye Study 2011 included 3468 individuals with a mean age of 64.6 ± 9.8 years (range:50-93 years. A detailed ophthalmic examination was performed. Based on a previous study with lumbar cerebrospinal fluid pressure (CSFP measurements, CSFP was calculated as CSFP[mmHg] = 0.44 × Body Mass Index[kg/m(2] + 0.16 × Diastolic Blood Pressure[mmHg]-0.18 × Age[Years]-1.91. RESULTS: Data of IOP and CSFP were available for 3353 (96.7% subjects. Taller body height was associated with higher CSFP (P<0.001; standardized correlation coefficient beta:0.13; regression coefficient B:0.29; 95% confidence interval (CI:0.25,0.33 after adjusting for male gender, urban region of habitation, higher educational level, and pulse rate. If TLCPD instead of CSFP was added, taller body height was associated with lower TLCPD (P<0.001;beta:-0.10;B:-0.20;95%CI:-0.25,-0.15. Correspondingly, higher CSFP was associated with taller body height (P = 0.003;beta:0.02;B:0.01;95%CI:0.00,0.02, after adjusting for age, gender, body mass index, pulse, systolic blood pressure, and blood concentration of cholesterol. If IOP was added to the model, higher CSFP was associated with higher IOP (P<0.001;beta:0.02;B:0.02;95%CI:0.01,0.03. TLCPD was associated with lower body height (P = 0.003;beta:-0.04;B -0.02,95%CI:-0.04,-0.01 after adjusting for age, body mass index, systolic blood pressure, pulse, blood concentrations of triglycerides, axial length, central corneal thickness, corneal curvature radius, and anterior chamber depth. Adding the prevalence of OAG to the multivariate analysis revealed, that taller body height was associated with a lower OAG prevalence (P = 0.03;beta:-0.03;B:-1.20;95%CI:-2.28,-0.12 after adjusting for

  18. Visual impairment and blindness in rural central India: the Central India Eye and Medical Study.

    Science.gov (United States)

    Nangia, Vinay; Jonas, Jost B; Gupta, Rajesh; Khare, Anshu; Sinha, Ajit

    2013-08-01

    The aim of the study was to investigate prevalence of visual impairment in rural central India. The population-based Central India Eye and Medical Study included 4711 subjects with an age of 30+ years. Presenting visual acuity (PRVA) and best-corrected visual acuity (BCVA) were recorded. Visual impairment and blindness were defined using the World Health Organization (WHO) standard and United States (US) standard. On the basis of PRVA and using WHO and US standards, 1049 [22%; 95% confidence interval (CI): 21.1, 23.5] subjects and 1290 (27%; 95% CI: 26.1, 28.7) subjects, respectively, were visually impaired, and 35 (0.7%; 95% CI: 0.5, 1.0) subjects and 116 (2.5%; 95% CI: 2.0, 2.9) subjects, respectively, were blind. The corresponding age-standardized prevalence figures were 17%, 21%, 0.5% and 2%, respectively. Using best-correcting glasses could eliminate PRVA-visual impairment/blindness in 729 subjects (67% of all subjects with visual impairment/blindness). On the basis of BCVA and using WHO and US standards, 333 (7%; 95% CI: 6.3, 7.8) subjects and 473 (10%; 95% CI: 9.2, 10.9) subjects, respectively, had visual impairment, and 22 (0.5%; 95% CI: 0.3, 0.7) and 31 (0.7%; 95% CI: 0.4, 0.9) subjects, respectively, were blind. Corresponding age-standardized prevalence figures were 5%, 8%, 0.4% and 0.5%, respectively. Causes for BCVA-visual impairment/blindness were cataract (75%), postoperative posterior capsular opacification (4%), surgical complications (2%), corneal opacifications (2%), age-related macular degeneration (2%), other macular diseases (1%), and glaucoma (1%). Age-standardized prevalence of PRVA-visual impairment/blindness (WHO definition) in the adult population of rural central India was 17%. Most frequent cause was undercorrected refractive error. Supply of correct glasses is the most efficient way to improve vision in the rural central India. © 2012 The Authors. Acta Ophthalmologica © 2012 Acta Ophthalmologica Scandinavica Foundation.

  19. Others' emotions teach, but not in autism: an eye-tracking pupillometry study.

    Science.gov (United States)

    Nuske, Heather J; Vivanti, Giacomo; Dissanayake, Cheryl

    2016-01-01

    Much research has investigated deficit in emotional reactivity to others in people with autism, but scant attention has been paid to how this deficit affects their own reactions to features of their environment (objects, events, practices, etc.). The present study presents a preliminary analysis on whether calibrating one's own emotional reactions to others' emotional reactions about features of the world, a process we term social-emotional calibration, is disrupted in autism. To examine this process, we used a novel eye-tracking pupillometry paradigm in which we showed 20 preschoolers with autism and 20 matched typically developing preschoolers' videos of an actor opening a box and reacting to the occluded object inside, with fear or happiness. We expected preschoolers to come to perceive the box as containing a positive or threatening stimulus through emotionally calibrating to the actor's emotional expressions. Children's mean pupil diameter (indicating emotional reactivity) was measured whilst viewing an up-close, visually identical image of the box before and then after the scene, and this difference was taken as an index of social-emotional calibration and compared between groups. Whilst the typically developing preschoolers responded more emotionally to the box after, compared to before the scene (as indexed by an increase in pupil size), those with autism did not, suggesting their reaction to the object was not affected by the actor's emotional expressions. The groups did not differ in looking duration to the emotional expressions; thus, the pupil dilation findings cannot be explained by differences in visual attention. More social-emotional calibration on the happy condition was associated with less severe autism symptoms. Through the measurement of physiological reactivity, findings suggest social-emotional calibration is diminished in children with autism, with calibration to others' positive emotions as particularly important. This study highlights a

  20. Hidden communicative competence: case study evidence using eye-tracking and video analysis.

    Science.gov (United States)

    Grayson, Andrew; Emerson, Anne; Howard-Jones, Patricia; O'Neil, Lynne

    2012-01-01

    A facilitated communication (FC) user with an autism spectrum disorder produced sophisticated texts by pointing, with physical support, to letters on a letterboard while their eyes were tracked and while their pointing movements were video recorded. This FC user has virtually no independent means of expression, and is held to have no literacy skills. The resulting data were subjected to a variety of analyses aimed at describing the relationship between the FC user's looking and pointing behaviours, in order to make inferences about the complex question of 'authorship'. The eye-tracking data present a challenge to traditional 'facilitator influence' accounts of authorship, and are consistent with the proposition that this FC user does indeed author the sophisticated texts that are attributed to him; he looks for longer at to-be-typed letters before typing them, and looks ahead to subsequent letters of words before the next letter of the word is typed.

  1. An Eye-tracking Study of Feature-based Choice in One-shot Games

    DEFF Research Database (Denmark)

    Devetag, Giovanna; Di Guida, Sibilla; Polonio, Luca

    2016-01-01

    for a subset of game outcomes. We analyze subjects’ eye movements while playing a series of two-person, 3x3 one-shot games in normal form. Games within each class differ by a set of descriptive features (i.e., features that can be changed without altering the game equilibrium properties). Data show...... with the highest average payoff" or "choose the strategy leading to an attractive and symmetric outcome" without (optimally) incorporating knowledge on the opponent’s behavior. Lookup patterns resulted being feature and game invariant, heterogeneous across subjects, but stable within subjects. Using a cluster...... analysis, we find correlations between eye-movements and choices; however, applying the Cognitive Hierarchy model to our data, we show that only some of the subjects present both information search patterns and choices compatible with a specific cognitive level. We also find a series of correlations...

  2. Neuroanatomical circuitry associated with exploratory eye movement in schizophrenia: a voxel-based morphometric study.

    Directory of Open Access Journals (Sweden)

    Linlin Qiu

    Full Text Available Schizophrenic patients present abnormalities in a variety of eye movement tasks. Exploratory eye movement (EEM dysfunction appears to be particularly specific to schizophrenia. However, the underlying mechanisms of EEM dysfunction in schizophrenia are not clearly understood. To assess the potential neuroanatomical substrates of EEM, we recorded EEM performance and conducted a voxel-based morphometric analysis of gray matter in 33 schizophrenic patients and 29 well matched healthy controls. In schizophrenic patients, decreased responsive search score (RSS and widespread gray matter density (GMD reductions were observed. Moreover, the RSS was positively correlated with GMD in distributed brain regions in schizophrenic patients. Furthermore, in schizophrenic patients, some brain regions with neuroanatomical deficits overlapped with some ones associated with RSS. These brain regions constituted an occipito-tempro-frontal circuitry involved in visual information processing and eye movement control, including the left calcarine cortex [Brodmann area (BA 17], the left cuneus (BA 18, the left superior occipital cortex (BA 18/19, the left superior frontal gyrus (BA 6, the left cerebellum, the right lingual cortex (BA 17/18, the right middle occipital cortex (BA19, the right inferior temporal cortex (BA 37, the right dorsolateral prefrontal cortex (BA 46 and bilateral precentral gyri (BA 6 extending to the frontal eye fields (FEF, BA 8. To our knowledge, we firstly reported empirical evidence that gray matter loss in the occipito-tempro-frontal neuroanatomical circuitry of visual processing system was associated with EEM performance in schizophrenia, which may be helpful for the future effort to reveal the underlying neural mechanisms for EEM disturbances in schizophrenia.

  3. Toxicological study of the molluscicidal latex of Euphorbia splendens: irritant action on skin and eye

    Directory of Open Access Journals (Sweden)

    J. C. B. R. Freitas

    1991-01-01

    Full Text Available Aqueous solutions of the molluscicidal latex of Euphorbia splendens are irritant to the rabbit eye in concentrations higher than 0.35% and to the rabbit skin in concentrations higher than 0.5%. Although this irritant potential does not proclude its use as a molluscicide, special precautions are recommended for hanbdling and application of the product and the hazard of skin tumor-promoting potencial should be carefully investigated before its use for schistosomiasis vector control.

  4. Rett syndrome: basic features of visual processing-a pilot study of eye-tracking.

    Science.gov (United States)

    Djukic, Aleksandra; Valicenti McDermott, Maria; Mavrommatis, Kathleen; Martins, Cristina L

    2012-07-01

    Consistently observed "strong eye gaze" has not been validated as a means of communication in girls with Rett syndrome, ubiquitously affected by apraxia, unable to reply either verbally or manually to questions during formal psychologic assessment. We examined nonverbal cognitive abilities and basic features of visual processing (visual discrimination attention/memory) by analyzing patterns of visual fixation in 44 girls with Rett syndrome, compared with typical control subjects. To determine features of visual fixation patterns, multiple pictures (with the location of the salient and presence/absence of novel stimuli as variables) were presented on the screen of a TS120 eye-tracker. Of the 44, 35 (80%) calibrated and exhibited meaningful patterns of visual fixation. They looked longer at salient stimuli (cartoon, 2.8 ± 2 seconds S.D., vs shape, 0.9 ± 1.2 seconds S.D.; P = 0.02), regardless of their position on the screen. They recognized novel stimuli, decreasing the fixation time on the central image when another image appeared on the periphery of the slide (2.7 ± 1 seconds S.D. vs 1.8 ± 1 seconds S.D., P = 0.002). Eye-tracking provides a feasible method for cognitive assessment and new insights into the "hidden" abilities of individuals with Rett syndrome.

  5. Eye Symptom Questionnaire to Evaluate Anterior Eye Health.

    Science.gov (United States)

    Woodward, Maria A; Valikodath, Nita G; Newman-Casey, Paula Anne; Niziol, Leslie M; Musch, David C; Lee, Paul P

    2017-06-14

    Ophthalmologists assess eye complaints with a careful history and eye examination; however, other types of physicians have limited tools to evaluate anterior segment (AS) eye diseases. We identified the eye symptom questions that providers should ask to help determine the presence and urgency of AS eye diseases. Persons with and without AS disease completed a self-report eye symptom questionnaire (ESQ) based on the National Institutes of Health Toolbox symptom items in an academic center's corneal and comprehensive eye clinics. Gold standard ophthalmic examination determined the presence and urgency of AS disease. The association between reported symptom severity and the probability of AS disease, or urgent AS disease, was evaluated using logistic regression models, and sensitivity and specificity of the ESQ were also calculated. A total of 324 eyes of 162 subjects were included in the study. Of these, AS disease was present in 255 eyes (79%); of which, 111 eyes showed urgent disease. Increasing symptom severity for eye pain (odds ratio [OR]=2.58; P<0.001), glare (OR=2.61; P=0.001), and blurry vision (OR=1.98; P<0.001) were associated with increased odds of AS disease. Increasing symptom severity for eye pain (OR=2.02; P<0.001), eye redness (OR=1.69; P=0.02), and blurry vision (OR=1.41, P=0.01) were associated with increased odds of urgent AS disease. For the primary analysis with mild symptoms considered relevant, the sensitivity of the ESQ to detect AS disease was 83% and to detect urgent AS disease was 92%. Symptoms of eye pain, glare, redness, and blurry vision indicate the presence and urgency of AS disease.

  6. Cross-sectional study of the association between a deepening of the upper eyelid sulcus-like appearance and wide-open eyes.

    Directory of Open Access Journals (Sweden)

    Shunsuke Nakakura

    Full Text Available BACKGROUND: Deepening of the upper eyelid sulcus (DUES is a common complication of prostaglandin F2α analog treatment, which causes cosmetic problems. However, identifying this condition using photographs is difficult due to such problems as the camera flash effects, blepharoptosis or wide-open eyes. PURPOSE: We investigated the association between a DUES-like appearance and wide-open eyes regarding the presence of wide-open eyes as a cause for overestimating the incidence of DUES. SUBJECTS AND METHODS: One eye and the forehead in 100 subjects (31 younger subjects, 30 older subjects and 39 patients with blepharoptosis were evaluated in the present study. Digital photographs of the subjects with natural open and wide-open eyes were taken with a flash. Five signs (a puffy eyelid, the presence/absence of the upper eyelid sulcus (UES, wrinkles on the forehead with natural open eyes and an increase in the number of wrinkles on the forehead and a DUES-like appearance with wide-open eyes were judged to be negative or positive by three independent observers. Univariate and multivariate logistic regression analyses were performed to determine the independent predictor(s of a DUES-like appearance with wide-open eyes. RESULTS: Fourteen subjects (four young, three old and seven subjects with blepharoptosis were judged to have a DUES-like appearance with wide-open eyes (14%. The only predictive factor was the presence of UES in the patients with natural open eyes (odds ratio = 17.244, 95% confidence interval: 3.447-86.270, P<0.001. Among the 12 UES-positive subjects, six (50% exhibited a DUES-like appearance with wide-open eyes. CONCLUSIONS: The presence of wide-open eyes can thus cause a DUES-like appearance. Blepharoptosis itself is not a predictive factor; however, care should be taken not to overestimate the incidence of DUES, especially in patients with UES with natural open eyes, as a DUES-like appearance can be caused by wide-open eyes, even in

  7. Macular Bruch's Membrane Length and Axial Length. The Beijing Eye Study.

    Directory of Open Access Journals (Sweden)

    Jost B Jonas

    Full Text Available To assess whether macular Bruch´s membrane gets lengthened in axial myopia.Using the enhanced depth imaging mode of spectral-domain optical coherence tomography and examining a subgroup of participants of the population-based cross-sectional Beijing Eye Study, we measured the length of Bruch´s membrane ("MacBMLength" from the fovea to the temporal edge of parapapillary gamma zone, and the distance between the fovea and the temporal optic disc border. Parapapillary gamma zone was defined as the parapapillary region without Bruch's membrane. We additionally measured ocular biometric parameters and assessed non-ophthalmologic variables.Measurements of MacBMLength were performed on 322 individuals. MacBMLength (mean: 3.99 ± 0.33 mm; range: 3.17-4.93 mm was not significantly associated with any systemic parameter or ocular biometric parameter. Gamma zone width (mean: 0.18 ± 0.30 mm; range: 0.00-2.61 mm was associated (multivariate analysis; correlation coefficient r:0.80 with longer axial length (P<0.001; standardized correlation coefficient beta: 0.60; non-standardized correlation coefficient B:0.11; 95%CI: 0.09,0.14 and with longer fovea-optic disc border distance (P<0.001; beta:0.28; B:0.19; 95%CI:0.14,0.25, but not with MacBMLength (P = 0.42. Fovea-temporal disc border distance (mean: 4.16 ± 0.44 mm; range: 3.17-5.86 mm was associated (overall correlation coefficient: 0.68 with longer axial length (P<0.001; beta: 0.36; B: 0.10; 95%CI: 0.06, 0.13, after adjusting for flatter anterior chamber depth (P = 0.003; beta:-0.14; B:-0.14; 95%CI: -0.23,-0.05 and wider parapapillary gamma zone (P<0.001; beta:0.42; B:0.62; 95%CI:0.44,0.81.In contrast to parapapillary gamma zone width and fovea-disc border distance, MacBMLength was not significantly associated with axial length. Axial elongation associated increase in fovea-disc distance may predominantly occur through development or elongation of parapapillary gamma zone, while macular Bruch´s membrane

  8. Four-Year Incidence and Progression of Visual Impairment in Latinos: The Los Angeles Latino Eye Study (LALES)

    Science.gov (United States)

    Varma, Rohit; Chung, Jessica; Foong, Althena W.P.; Torres, Mina; Choudhury, Farzana; Azen, Stanley P.

    2010-01-01

    Purpose To determine the 4-year incidence of visual impairment (VI) and blindness and worsening of visual acuity in adult Latinos/Hispanics aged 40 years and older. Design Population-based, longitudinal study. Methods Participants underwent a detailed ophthalmologic examination including assessing both presenting binocular (PVA) and best-corrected distance visual acuity (BCVA) in both eyes using a standard ETDRS protocol. The main outcome measures are 4-year incidence of visual impairment and blindness based on PVA or BCVA in the better seeing eye and defined as 1) baseline visual acuity (PVA or BCVA)≥20/40 and a follow-up PVA or BCVA20/200 and a follow-up PVA≤20/200 respectively. Monocular worsening was defined as a decrease of ≥5, 10, and 15 letters in either eye. Results Four thousand six hundred and fifty eight participants were examined at baseline and the 4-year follow-up. The 4-year incidence of presenting binocular VI and blindness was 2.9% and 0.3%. The 4-year incidence of best corrected VI and blindness was 1.2% and 0.3%. The 4-year incidence of monocular worsening by ≥5, 10, and 15 letters was 24.8%, 8.5% and 3.1% respectively. The incidence of VI and blindness increased with age at baseline (Pvisual impairment and blindness should focus on the older Latino population. PMID:20399925

  9. Factors associated with myopia in school children in China: the Beijing childhood eye study.

    Directory of Open Access Journals (Sweden)

    Qi Sheng You

    Full Text Available PURPOSE: To assess factors associated with myopia in school children in rural and urban parts of Greater Beijing. METHODS: The Beijing Pedriatic Eye Study was a population-based cross-sectional study, in which one school of each level (primary, junior high, senior high was randomly selected from nine randomly selected districts out of 18 districts of Greater Beijing. The children underwent non-cylcoplegic refractometry and their parents an interview. RESULTS: Of 16,771 eligible students, 15,066 (89.8% children (7,769 (51.6% girls participated, with 8,860 (58.8% participants living in the rural region. Mean age was 13.2±3.4 years (range:7-18 years. In multivariate analysis, prevalence of myopia (defined as ≤-1.00 diopters was associated with higher age (Odds ratio(OR:1.37; 95% confidence interval(CI:1.35,1.39, female gender (OR:1.35;95%CI:1.25,1.47, key school type (OR:0.77;95%CI: 0.70,0.85, higher family income (OR:1.04;95%CI:1.01,1.07, parental myopia (OR:1.46;95%CI:1.40,1.53, dim reading illumination (OR:0.93;95%CI: 0.88,0.98, longer daily studying duration (OR:1.10;95%CI:1.06,1.15, shorter duration of watching television (or computer (OR:0.93;95%CI:0.89,0.97, higher self-reported protein intake (OR:0.94;95%CI:0.90,0.99, feeling well about life and status (OR:0.93;95%CI:0.89,0.98, and feeling tired or dizzy (OR:0.94;95%CI:0.91,0.97. Prevalence of high myopia (defined as ≤-6.00 diopters was associated with higher age (OR:1.43;95%CI:1.38, 1.48, key school type (OR:0.61;95%CI:0.49,0.74, family income (OR:1.07;95%CI:1.02,1.13, parental myopia (OR:1.65;95%CI:1.54,1.76, dim reading illumination (OR:0.86;95%CI:0.77,0.96, less rest during studying (OR:1.18;95%CI:1.10,1.27, feeling well about life and studying (OR:0.88;95%CI: 0.81,0.96 and feeling dizzy or tired (OR:0.93;95%CI:0.87,0.99. Prevalence of high myopia (defined as ≤-8.00 diopters was significantly associated with higher age (OR:1.39;95%CI:1.31,1.48;, key school type (OR:0.61;95%CI:0

  10. Eye and hair colour, skin type and constitutive skin pigmentation as risk factors for basal cell carcinoma and cutaneous malignant melanoma. A Danish case-control study

    DEFF Research Database (Denmark)

    Lock-Andersen, J; Drzewiecki, K T; Wulf, H C

    1999-01-01

    the present hair colour and eye colour, and the constitutive skin pigmentation was measured objectively by skin reflectance of UV unexposed buttock skin. There were no differences between basal cell carcinoma cases and controls in hair colour or eye colour or constitutive skin pigmentation, but more cases......To assess the importance of hair and eye colour, skin type and constitutive skin pigmentation as risk factors for basal cell carcinoma and cutaneous malignant melanoma in fair-skinned Caucasians, we conducted two identical case-control studies in Denmark. We studied 145 cases with basal cell...

  11. The British Asian Community Eye Study: Outline of results on the prevalence of eye disease in British Asians with origins from the Indian subcontinent

    Directory of Open Access Journals (Sweden)

    Abdul Rauf

    2013-01-01

    Full Text Available Background: Asians from the Indian Subcontinent form the largest ethnic minority in the United Kingdom. Data on the prevalence of visually-impairing eye conditions in this population are vital for planning eye health care services. Materials and Methods: This survey was based in the two London boroughs with the largest Asian populations. Subjects originating from the Indian Subcontinent were identified from GP practice records. All subjects were asked about demographic details and were given a full ophthalmological examination. The severity of cataract, glaucoma, diabetic retinopathy, and age-related maculopathy was recorded. Blindness was defined as logMAR visual acuity of 0.99 (Snellen equivalence 20/200 in the better eye or worse, ′low vision′ was defined as Snellen equivalence of 20/63 or worse (logMAR 0.5 or higher, and visual impairment was defined as visual acuity worse than 20/40. Results: The median age was 56 years. Two hundred and eighty four subjects did not attend for eye examination. Of the 922 examined, 128 subjects (13.9% were ′visually impaired,′ 39 (4.2% had ′low vision,′ and 6 (0.7% were bilaterally blind. The overall prevalence of cataract, open-angle glaucoma, age-related macular degeneration, and diabetic retinopathy were 77%, 1.0%, 8.7%, and 8.8%, respectively. Conclusion: Visual impairment rates amongst Asians seem to be similar to Caucasian populations in the UK. The prevalence of cataract and diabetic retinopathy is higher, while the risk of ARMD and OAG are comparable. In view of the high cataract prevalence, a more detailed assessment of the visual profile and factors limiting healthcare accessibility in this community are needed.

  12. Developing a Novel Eye Tracking Paradigm to Assess Mild Traumatic Brain Injury: A Feasibility Study of the Bethesda Eye and Attention Measure (BEAM)

    Science.gov (United States)

    2012-10-01

    voluntary and involuntary fixation mechanisms ( Guyton & Hall, 2006, 2011). Voluntary fixation movements allow a person to willfully move their eyes...onto a given object, and they are controlled in bilateral cortical fields in the premotor cortex of the frontal lobes ( Guyton & Hall, 2006, 2011...controlled by secondary visual areas in the occipital cortex ( Guyton & Hall, 2006, 2011). Involuntary and voluntary fixation movements work in concert

  13. OH Fluorescence and Prompt Emission in comet 103P/Hartley 2 observed by EPOXI mission and expected results for comet 67P/Churyumov-Gerasimenko observed by Rosetta/OSIRIS WAC camera

    Science.gov (United States)

    La Forgia, F.; A'Hearn, M. F.; Lazzarin, M.; Magrin, S.; Bodewits, D.; Bertini, I.; Pajola, M.; Barbier, C.; Sierks, H.

    2014-04-01

    The OH radical, observed in cometary comae, is the direct dissociation product of water. Given the strong A2∑ - X2II (0, 0) emission band in the near-UV at 308.5 nm due to resonance fluorescence, the OH radical has been used, for years, as a tracer of the water parent molecule. Specifically, the OH fluorescence band provides an immediate tool to monitor the water production rate and its variations with the comet's heliocentric distance, rotational period and possible activity changes. Photolysis of water in cometary comae gives rise, with a non negligible branching ratio, to OH fragments in the first electronically excited state (OH*). This state is very unstable, with a lifetime of about 10-6s (Becker and Haaks, 1973), therefore OH* molecules promptly decay to the ground state. This process, generally referred to as prompt emission (PE), is responsible for an emission band in the near-UV ranging approximatelly from 306 to 325 nm. Original studies and tentative detections of OH PE have been put forth by Bertaux (1986), Budzien and Feldman (1991), Bonev et al. (2004), A'Hearn et al. (2007) using ground and space observations. Both from the above mentioned works together with our analysis, this process is expected to be prominent at short distances from the nucleus, where there is high density of water molecules, requiring the need of spacecraft observations to reach the necessary resolution. The hyperactive Jupiter family comet 103P/Hartley 2 has been visited by EPOXI spacecraft on 4 November 2010 at a minimum distance of 694 km, when it was at 1.064 AU from the Sun (A'Hearn et al. 2011). We present the analysis of photometric observations in OH filter acquired by MRI camera onboard EPOXI used to investigate the spatial distribution of OH in the coma of Hartley 2. The data revealed a radial OH structure within 35 km from the nucleus, appearing to be coming directly from the nucleus, in the region of the central waist. A theoretical computation evidencing a strong

  14. Your Eyes

    Science.gov (United States)

    ... people you know — like your grandparents — probably wear glasses. To the Brain! Think of the optic nerve as the great messenger in the back of your eye. The rods and cones of the retina change the colors and shapes you see into millions of nerve ...

  15. Towards a framework for analysis of eye-tracking studies in the three dimensional environment: a study of visual search by experienced readers of endoluminal CT colonography.

    Science.gov (United States)

    Helbren, E; Halligan, S; Phillips, P; Boone, D; Fanshawe, T R; Taylor, S A; Manning, D; Gale, A; Altman, D G; Mallett, S

    2014-05-01

    Eye tracking in three dimensions is novel, but established descriptors derived from two-dimensional (2D) studies are not transferable. We aimed to develop metrics suitable for statistical comparison of eye-tracking data obtained from readers of three-dimensional (3D) "virtual" medical imaging, using CT colonography (CTC) as a typical example. Ten experienced radiologists were eye tracked while observing eight 3D endoluminal CTC videos. Subsequently, we developed metrics that described their visual search patterns based on concepts derived from 2D gaze studies. Statistical methods were developed to allow analysis of the metrics. Eye tracking was possible for all readers. Visual dwell on the moving region of interest (ROI) was defined as pursuit of the moving object across multiple frames. Using this concept of pursuit, five categories of metrics were defined that allowed characterization of reader gaze behaviour. These were time to first pursuit, identification and assessment time, pursuit duration, ROI size and pursuit frequency. Additional subcategories allowed us to further characterize visual search between readers in the test population. We propose metrics for the characterization of visual search of 3D moving medical images. These metrics can be used to compare readers' visual search patterns and provide a reproducible framework for the analysis of gaze tracking in the 3D environment. This article describes a novel set of metrics that can be used to describe gaze behaviour when eye tracking readers during interpretation of 3D medical images. These metrics build on those established for 2D eye tracking and are applicable to increasingly common 3D medical image displays.

  16. Axial Globe Position Measurement: A Prospective Multicenter Study by the International Thyroid Eye Disease Society.

    Science.gov (United States)

    Bingham, Chad M; Sivak-Callcott, Jennifer A; Gurka, Matthew J; Nguyen, John; Hogg, Jeffery P; Feldon, Steve E; Fay, Aaron; Seah, Lay-Leng; Strianese, Diego; Durairaj, Vikram D; Uddin, Jimmy; Devoto, Martin H; Harris, Matheson; Saunders, Justin; Osaki, Tammy H; Looi, Audrey; Teo, Livia; Davies, Brett W; Elefante, Andrea; Shen, Sunny; Realini, Tony; Fischer, William; Kazim, Michael

    2016-01-01

    Identify a reproducible measure of axial globe position (AGP) for multicenter studies on patients with thyroid eye disease (TED). This is a prospective, international, multicenter, observational study in which 3 types of AGP evaluation were examined: radiologic, clinical, and photographic. In this study, CT was the modality to which all other methods were compared. CT AGP was measured from an orthogonal line between the anterior lateral orbital rims to the cornea. All CT measurements were made at a single institution by 3 individual clinicians. Clinical evaluation was performed with exophthalmometry. Three clinicians from each clinical site assessed AGP with 3 different exophthalmometers and horizontal palpebral width using a ruler. Each physician made 3 separate measurements with each type of exophthalmometer not in succession. All photographic measurements were made at a single institution. AGP was measured from lateral photographs in which a standard marker was placed at the anterior lateral orbital rim. Horizontal and vertical palpebral fissure were measured from frontal photographs. Three trained readers measured 3 separate times not in succession. Exophthalmometry and photography method validity was assessed by agreement with CT (mean differences calculation, intraclass correlation coefficients [ICCs], Bland-Altman figures). Correlation between palpebral fissure and CT AGP was assessed with Pearson correlation. Intraclinician and interclinician reliability was evaluated using ICCs. Sixty-eight patients from 7 centers participated. CT mean AGP was 21.37 mm (15.96-28.90 mm) right and 21.22 mm (15.87-28.70 mm) left (ICC 0.996 and 0.995). Exophthalmometry AGP fell between 18 mm and 25 mm. Intraclinician agreement across exophthalmometers was ideal (ICC 0.948-0.983). Agreement between clinicians was greater than 0.85 for all upright exophthalmometry measurements. Photographic mean AGP was 20.47 mm (10.92-30.88 mm) right and 20.30 mm (8.61-28.72

  17. Modern sports eye injuries.

    Science.gov (United States)

    Capão Filipe, J A; Rocha-Sousa, A; Falcão-Reis, F; Castro-Correia, J

    2003-11-01

    To determine the severity and long term sequelae of eye injuries caused by modern sports that could be responsible for significant ocular trauma in the future. Prospective observational study of 24 (25 eyes) athletes with sports related ocular injuries from health clubs, war games, adventure, radical and new types of soccer, presenting to an eye emergency department between 1992 and 2002 (10 years). Modern sports were responsible for 8.3% of the 288 total sports eye injuries reported. Squash (29.2%) was the most common cause, followed by paintball (20.8%) and motocross (16.6%). The most common diagnosis during the follow up period was retinal breaks (20%). 18 (75%) patients sustained a severe injury. The final visual acuity remained <20/100 in two paintball players. Ocular injuries resulting from modern sports are often severe. Adequate instruction of the participants in the games, proper use of eye protectors, and a routine complete ophthalmological examination after an eye trauma should be mandatory.

  18. Risk factors for hyperopia and myopia in preschool children the multi-ethnic pediatric eye disease and Baltimore pediatric eye disease studies.

    Science.gov (United States)

    Borchert, Mark S; Varma, Rohit; Cotter, Susan A; Tarczy-Hornoch, Kristina; McKean-Cowdin, Roberta; Lin, Jesse H; Wen, Ge; Azen, Stanley P; Torres, Mina; Tielsch, James M; Friedman, David S; Repka, Michael X; Katz, Joanne; Ibironke, Josephine; Giordano, Lydia

    2011-10-01

    To describe the risk factors associated with hyperopia and myopia among children 6 to 72 months of age. Population-based cross-sectional study. Population-based samples of 9970 children 6 to 72 months of age from Los Angeles County, California, and Baltimore, Maryland. Participants were preschool African-American, Hispanic, and non-Hispanic white children (n = 9770) from Los Angeles, California, and Baltimore, Maryland. Parental questionnaires and a comprehensive eye examination were administered. Demographic, behavioral, and clinical risk factors associated with hyperopia (≥2.00 diopters [D]) and myopia (≤-1.00 D) were determined. Odds ratios (ORs) for risk factors associated with myopia and hyperopia. Compared with non-Hispanic whites, African-American (OR, 6.0) and Hispanic (OR, 3.2) children were more likely to be myopic. Children 6 to 35 months of age were more likely to be myopic compared with those 60 to 72 months of age (OR, ≥1.7). Compared with African-American children, non-Hispanic white (OR, 1.63) and Hispanic (OR, 1.49) children were more likely to be hyperopic. Children whose parents had health insurance (OR, 1.5) and those with a history of maternal smoking during pregnancy (OR, 1.4) were more likely to have hyperopia. Astigmatism of 1.5 D or more at any axis was associated with myopia (OR, 4.37) and hyperopia (OR, 1.43). Children in specific racial or ethnic groups and age groups are at higher risk of having myopia and hyperopia. Cessation of maternal smoking during pregnancy may reduce the risk of hyperopia in these children. Given that both myopia and hyperopia are risk factors for the development of amblyopia and strabismus, these risk factors should be considered when developing guidelines for screening and intervention in preschool children. The author(s) have no proprietary or commercial interest in any materials discussed in this article. Copyright © 2011 American Academy of Ophthalmology. Published by Elsevier Inc. All rights reserved.

  19. A thermographic study on eyes affected by Age-related Macular Degeneration: Comparison among various forms of the pathology and analysis of risk factors

    Science.gov (United States)

    Matteoli, Sara; Finocchio, Lucia; Biagini, Ilaria; Giacomelli, Giovanni; Sodi, Andrea; Corvi, Andrea; Virgili, Gianni; Rizzo, Stanislao

    2016-05-01

    The aims of this study are to investigate (1) the ocular thermographic profiles in eyes affected by Age related Macular Degeneration (AMD) and age-matched controls to detect possible hemodynamic abnormalities that could be involved in the pathogenesis of the disease, (2) whether any risk factors associated with the disease could affect the development of a form of AMD rather than another. Thirty-four eyes with Age-Related Maculopathy (ARM), 41 eyes with dry AMD, 60 eyes affected by wet AMD, and 74 eyes with fibrotic AMD were included in the study. The control group consisted of 48 healthy eyes. Exclusion criteria were represented by any other ocular diseases other than AMD, tear film abnormalities, systemic cardiovascular abnormalities, systemic diseases and a body temperature higher than 37.5 °C. A total of 210 eyes without pupil dilation were investigated by infrared thermography (FLIR A320). The Ocular Surface Temperature (OST) of five ocular areas was calculated by means of an image processing technique from the infrared images. Two-sample t-test, one-way ANOVA test and multivariate analysis were used for statistical analyses. ANOVA analyses showed no significant differences among AMD groups (P-value > 0.05), however, OST in AMD patients was significantly lower than in controls (P-value wet AMD instead of dry AMD. Infrared thermography may be a helpful, non-invasive and not time-consuming method to be used in the management of patients with this common degenerative maculopathy.

  20. Development of an Accommodation-Dependent Eye Model and Studying the Effects of Accommodation on Electron and Proton Dose Conversion Coefficients

    Directory of Open Access Journals (Sweden)

    Alireza Vejdani-Noghreiyan

    2016-06-01

    Full Text Available Introduction International Commission on Radiological Protection (ICRP has provided a comprehensive discussion on threshold dose for radiation-induced cataract in ICRP publication 116. Accordingly, various parts of the eye lens have different radio-sensitivities. Recently, some studies have been performed to develop a realistic eye model with the aim of providing accurate estimation of fluence-to-dose conversion coefficients for different parts of the eye. However, the effect of accommodation, which changes the lens shape and pupil size, on dose conversion coefficients has not been considered yet. In this study, we purport to develop an accommodation-dependent eye model and to study the effects of accommodation on the electron and proton fluence-to-dose conversion coefficients. Materials and Methods Herein, a modified eye model was developed by considering the effects of accommodation on the lens shape and pupil size. In addition, MCNPX 2.6 Monte Carlo transport code was used to calculate the effects of  eye lens accommodation on electron and proton fluence-to-dose conversion coefficients. Results Calculation of dose conversion coefficients demonstrated that the accommodation causes up to 40% discrepancy for fluence-to-dose conversion coefficients of electrons in the range of 600 to 800 keV, which is due to the change of eye lens shape during the accommodation of the eye. Conclusion Since the accommodation of the eye change the lens shape and pupil size, it has considerable effect on fluence-to-dose conversion coefficients of electrons at some ranges of incident particle energies that should be considered in simulation. However, the fluctuation of dose conversion coefficients of protons is negligible.

  1. Development of online use of theory of mind during adolescence: An eye-tracking study.

    Science.gov (United States)

    Symeonidou, Irene; Dumontheil, Iroise; Chow, Wing-Yee; Breheny, Richard

    2016-09-01

    We investigated the development of theory of mind use through eye-tracking in children (9-13years old, n=14), adolescents (14-17.9years old, n=28), and adults (19-29years old, n=23). Participants performed a computerized task in which a director instructed them to move objects placed on a set of shelves. Some of the objects were blocked off from the director's point of view; therefore, participants needed to take into consideration the director's ignorance of these objects when following the director's instructions. In a control condition, participants performed the same task in the absence of the director and were told that the instructions would refer only to items in slots without a back panel, controlling for general cognitive demands of the task. Participants also performed two inhibitory control tasks. We replicated previous findings, namely that in the director-present condition, but not in the control condition, children and adolescents made more errors than adults, suggesting that theory of mind use improves between adolescence and adulthood. Inhibitory control partly accounted for errors on the director task, indicating that it is a factor of developmental change in perspective taking. Eye-tracking data revealed early eye gaze differences between trials where the director's perspective was taken into account and those where it was not. Once differences in accuracy rates were considered, all age groups engaged in the same kind of online processing during perspective taking but differed in how often they engaged in perspective taking. When perspective is correctly taken, all age groups' gaze data point to an early influence of perspective information.

  2. Major review: ocular sighting dominance: a review and a study of athletic proficiency and eye-hand dominance in a collegiate baseball team.

    Science.gov (United States)

    Portal, J M; Romano, P E

    1998-01-01

    Laterality preference in sensory and motor functions of symmetrically disposed organisms have been studied for centuries. The relation between handedness and the eyes and vision (ocular sighting dominance) has been a focal point despite their physiologic dissimilarity. To examine a college varsity baseball team for handedness and ocular sighting dominance to determine if their patterns of eye-hand dominance differed from the normal population and/or contributed to their individual relative success compared to their peers. Specifically: whether crossed eye- hand dominance favors the batter and uncrossed eye-hand dominance favors the pitcher. Twenty five UF varsity players were examined. All were male. Their visual acuity, stereoscopic vision, ocular motility and ocular sighting dominance were determined, the last by a pointing test which allowed the diagnosis of a central form of ocular dominance, but was not per se affected by handedness. Handedness was determined by preferred arm for throwing or hitting. No subject was ambidextrous. A control population was established consisting of the first 100 consecutive adults seen by the first author in the UF Eye Center with 20/20 vision O.U. and a normal eye exam. The control group displayed eye-hand dominance patterns similar to those previously reported in the literature for the general population. In the experimental group of baseball players, the incidence of conventionally predominant (in normals) ipsilateral or uncrossed eye-hand dominance was much lower (39%) than the normal control population (65%). The incidence of contralateral or crossed eye- hand dominance was 35%, twice that of the normal control population (18%) (pdominance with right or left handedness was 26% or 50% higher than a normal control population (17%) (pdominance, whether right or left handed, were the most successful players in both pitching and batting. Pitchers who were uncrossed eye-hand dominant were distinctly more successful than crossed

  3. Consideration of growth (age)-related effects on globe size and corneal thickness in ovine eyes for use in laboratory studies.

    Science.gov (United States)

    Doughty, Michael J

    2017-07-01

    The aim was to assess differences in eyeball mass, corneal diameter and central corneal thickness in slaughterhouse-procured ovine eyes. Over a 12-year period, measurements of eye globe mass, horizontal corneal diameter and central corneal thickness were routinely undertaken within two hours post-mortem. Only eyes free of obvious mechanical damage or disease were used. From measurements on 736 quality-selected and trimmed eyes, globe wet mass ranged from 10.4 to 25.2 g, horizontal corneal diameter from 19.0 to 26.5 mm and central corneal thickness measured by ultrasonic pachymetry from 0.543 to 0.836 mm (with an overall average of 690 ± 0.056 mm). The ocular globe mass was strongly correlated to horizontal corneal diameter (r(2)  = 0.829). Central corneal thickness correlated with globe mass (r = 0.543) and to horizontal corneal diameter (r = 0.402). Based on the different anatomical measurements, a lamb's eye would be expected to have a thinner cornea (average 0.640 mm) than that of an adult outbred ewe (average 0.730 mm). In freshly procured eyes showing signs of slight corneal oedema, central corneal thickness was greater (average 0.856 ± 0.052 mm) and up to 24 hours of cold storage resulted in predictable increases in central corneal thickness of six to 24 per cent, especially in eyes showing signs of corneal oedema before storage. Based on the correlations obtained, differences in ovine eyes can be attributed to growth-related differences in the animals and thus, indirectly to their expected ages. A simple measure of the horizontal corneal diameter in ovine eyes used for laboratory studies would be a useful indicator in reporting these studies. © 2016 Optometry Australia.

  4. Intraocular pressure and estimated cerebrospinal fluid pressure. The Beijing Eye Study 2011.

    Directory of Open Access Journals (Sweden)

    Ya Xing Wang

    Full Text Available PURPOSE: To examine a potential association between intraocular pressure (IOP and cerebrospinal fluid pressure (CSFP in a population-based setting. METHODS: The population-based Beijing Eye Study 2011 included 3468 individuals with a mean age of 64.6±9.8 years (range: 50-93 years. A detailed ophthalmic examination was performed. Based on a previous study with lumbar cerebrospinal fluid pressure (CSFP measurements, CSFP was calculated as CSFP [mm Hg] = 0.44×Body Mass Index [kg/m2]+0.16×Diastolic Blood Pressure [mm Hg]-0.18×Age [Years]. RESULTS: In multivariate analysis, IOP was associated with higher estimated CSFP (P<0.001; standardized correlation coefficient beta: 0.27; regression coefficient B: 0.20; 95% confidence interval (CI: 0.16, 0.24, after adjusting for thinner central corneal thickness (P<0.001; beta: 0.45; B: 0.04;95%CI: 0.04,0.04, smaller corneal curvature radius (P<0.001; beta:-0.11; B:-1.13;95%CI:-1.61,-0.64, shallower anterior chamber depth (P = 0.01; beta:-0.05; B:-0.33;95%CI:-0.59,-0.08 and longer axial length (P = 0.002; beta: 0.08; B: 0.20;95%CI: 0.08,0.32, and after adjusting for the systemic parameters of higher pulse rate (P<0.001; beta: 0.08; B: 0.02;95%CI: 0.01,0.03, higher prevalence of arterial hypertension (P = 0.002; beta: 0.06; B: 0.32;95%CI: 0.12,0.53, frequency of drinking alcohol (P = 0.02; beta: 0.04; B: 0.09;95%CI: 0.01,0.17, higher blood concentration of triglycerides (P = 0.001; beta: 0.06; B: 0.06;95%CI: 0.02,0.10 and cholesterol (P = 0.049; beta: 0.04; B: 0.08;95%CI: 0.00,0.17, and body mass index (P<0.001; beta:-0.13; B:-0.09;95%CI:-0.13,-0.06. In a parallel manner, estimated CSFP (mean: 10.8±3.7 mm Hg was significantly associated with higher IOP (P<0.001; beta: 0.13; B: 0.18;95%CI: 0.13,0.23 after adjusting for rural region of habitation (P<0.001; beta:-0.37; B:-2.78;95%CI:-3.07,-2.48, higher systolic blood pressure (P<0.001; beta: 0.34; B: 0.06;95%CI: 0.05,0.07, higher

  5. Sunlight and the 10-year incidence of age-related maculopathy: the Beaver Dam Eye Study.

    Science.gov (United States)

    Tomany, Sandra C; Cruickshanks, Karen J; Klein, Ronald; Klein, Barbara E K; Knudtson, Michael D

    2004-05-01

    progression of ARM or its associated lesions. Few significant relationships between environmental exposure to light and the 10-year incidence and progression of ARM were found in the Beaver Dam Eye Study. Consistent with results from the baseline and 5-year follow-up examinations, significant associations were found between extended exposure to the summer sun and the 10-year incidence of early ARM and increased retinal pigment. A protective effect of hat and sunglasses use by participants while in their teens and 30s against the 10-year incidence of soft indistinct drusen and retinal pigment epithelial depigmentation was also found, but only in those who reported the highest amount of sun exposure during the same periods.

  6. Why Do Eyes Water?

    Science.gov (United States)

    ... Lifesaver Kids Talk About: Coaches Why Do Eyes Water? KidsHealth > For Kids > Why Do Eyes Water? Print ... out of your nose. continue Why Do Eyes Water? Eyes water for lots of different reasons besides ...

  7. Eye muscle repair - discharge

    Science.gov (United States)

    ... Lazy eye repair - discharge; Strabismus repair - discharge; Extraocular muscle surgery - discharge ... You or your child had eye muscle repair surgery to correct eye muscle ... term for crossed eyes is strabismus. Children most often ...

  8. Why Do Eyes Water?

    Science.gov (United States)

    ... Happens in the Operating Room? Why Do Eyes Water? KidsHealth > For Kids > Why Do Eyes Water? A ... out of your nose. continue Why Do Eyes Water? Eyes water for lots of different reasons besides ...

  9. About the Eye

    Medline Plus

    Full Text Available ... eye behind the iris that helps to focus light on the retina. It allows the eye to ... of the eye. It regulates the amount of light entering the eye through the pupil. Pupil (PYOO- ...

  10. Recommended Sports Eye Protectors

    Science.gov (United States)

    ... Financial Assistance Information Vision Screening and Eye Exams Zika Virus and Vision Eye Problems Eye Problems Amblyopia ( ... Eye Health Report Reports and External Resources The Cost of Vision Problems The Future of Vision Vision ...

  11. Eye Safety at Home

    Science.gov (United States)

    ... Financial Assistance Information Vision Screening and Eye Exams Zika Virus and Vision Eye Problems Eye Problems Amblyopia ( ... Eye Health Report Reports and External Resources The Cost of Vision Problems The Future of Vision Vision ...

  12. Eye Safety at Work

    Science.gov (United States)

    ... Financial Assistance Information Vision Screening and Eye Exams Zika Virus and Vision Eye Problems Eye Problems Amblyopia ( ... Eye Health Report Reports and External Resources The Cost of Vision Problems The Future of Vision Vision ...

  13. Eye Movement Disorders

    Science.gov (United States)

    ... work properly. There are many kinds of eye movement disorders. Two common ones are Strabismus - a disorder in ... the eyes, sometimes called "dancing eyes" Some eye movement disorders are present at birth. Others develop over time ...

  14. About the Eye

    Medline Plus

    Full Text Available ... eye behind the iris that helps to focus light on the retina. It allows the eye to ... of the eye. It regulates the amount of light entering the eye through the pupil. Pupil (PYOO- ...

  15. Conjunctivitis (Pink Eye)

    Science.gov (United States)

    ... that can be embedded on web pages. Conjunctivitis (Pink Eye) One-Page Overview Pink, itchy eyes? Conjunctivitis – ... protect yourself from getting and spreading pink eye . Pink Eye: What To Do Discusses causes and treatment, ...

  16. Eye Disease Simulations

    Science.gov (United States)

    ... USAJobs Home > Eye Health Information > Eye Disease Simulations Eye Disease Simulations Age-Related Macular Degeneration Cataract Diabetic ... information page Back to top Diabetic Retinopathy Diabetic Eye Disease information page Back to top Glaucoma Glaucoma ...

  17. Eye Involvement in TSC

    Science.gov (United States)

    ... Privacy Policy Sitemap Learn Engage Donate About TSC Eyes Campbell (1905) first described the eye involvement in ... some form of eye involvement. Nonretinal and Retinal Eye Findings Facial angiofibromas may involve the eyelids of ...

  18. Eye Complications in IBD

    Science.gov (United States)

    ... Home > Resources > Eye Complications in IBD Go Back Eye Complications in IBD Email Print + Share Approximately 10% ... doctor’s attention sooner rather than later. TYPES OF EYE DISORDERS UVEITIS One of the most common eye ...

  19. Social attention in ASD: A review and meta-analysis of eye-tracking studies.

    Science.gov (United States)

    Chita-Tegmark, Meia

    2016-01-01

    Determining whether social attention is reduced in Autism Spectrum Disorder (ASD) and what factors influence social attention is important to our theoretical understanding of developmental trajectories of ASD and to designing targeted interventions for ASD. This meta-analysis examines data from 38 articles that used eye-tracking methods to compare individuals with ASD and TD controls. In this paper, the impact of eight factors on the size of the effect for the difference in social attention between these two groups are evaluated: age, non-verbal IQ matching, verbal IQ matching, motion, social content, ecological validity, audio input and attention bids. Results show that individuals with ASD spend less time attending to social stimuli than typically developing (TD) controls, with a mean effect size of 0.55. Social attention in ASD was most impacted when stimuli had a high social content (showed more than one person). This meta-analysis provides an opportunity to survey the eye-tracking research on social attention in ASD and to outline potential future research directions, more specifically research of social attention in the context of stimuli with high social content.

  20. Reading during the composition of multi-sentence texts: an eye-movement study.

    Science.gov (United States)

    Torrance, Mark; Johansson, Roger; Johansson, Victoria; Wengelin, Åsa

    2016-09-01

    Writers composing multi-sentence texts have immediate access to a visual representation of what they have written. Little is known about the detail of writers' eye movements within this text during production. We describe two experiments in which competent adult writers' eye movements were tracked while performing short expository writing tasks. These are contrasted with conditions in which participants read and evaluated researcher-provided texts. Writers spent a mean of around 13 % of their time looking back into their text. Initiation of these look-back sequences was strongly predicted by linguistically important boundaries in their ongoing production (e.g., writers were much more likely to look back immediately prior to starting a new sentence). 36 % of look-back sequences were associated with sustained reading and the remainder with less patterned forward and backward saccades between words ("hopping"). Fixation and gaze durations and the presence of word-length effects suggested lexical processing of fixated words in both reading and hopping sequences. Word frequency effects were not present when writers read their own text. Findings demonstrate the technical possibility and potential value of examining writers' fixations within their just-written text. We suggest that these fixations do not serve solely, or even primarily, in monitoring for error, but play an important role in planning ongoing production.

  1. Route planning with transportation network maps: an eye-tracking study.

    Science.gov (United States)

    Grison, Elise; Gyselinck, Valérie; Burkhardt, Jean-Marie; Wiener, Jan Malte

    2017-09-01

    Planning routes using transportation network maps is a common task that has received little attention in the literature. Here, we present a novel eye-tracking paradigm to investigate psychological processes and mechanisms involved in such a route planning. In the experiment, participants were first presented with an origin and destination pair before we presented them with fictitious public transportation maps. Their task was to find the connecting route that required the minimum number of transfers. Based on participants' gaze behaviour, each trial was split into two phases: (1) the search for origin and destination phase, i.e., the initial phase of the trial until participants gazed at both origin and destination at least once and (2) the route planning and selection phase. Comparisons of other eye-tracking measures between these phases and the time to complete them, which depended on the complexity of the planning task, suggest that these two phases are indeed distinct and supported by different cognitive processes. For example, participants spent more time attending the centre of the map during the initial search phase, before directing their attention to connecting stations, where transitions between lines were possible. Our results provide novel insights into the psychological processes involved in route planning from maps. The findings are discussed in relation to the current theories of route planning.

  2. Stereo-PIV study of flow inside an eye under cataract surgery

    Science.gov (United States)

    Sakakibara, Jun; Yamashita, Masaki; Kobayashi, Tatsuya; Kaji, Yuichi; Oshika, Tetsuro

    2012-04-01

    We measured velocity distributions in the anterior chamber of porcine eyes under simulated cataract surgery using stereoscopic particle image velocimetry (stereo-PIV). The surface of the cornea was detected based on the images of laser-induced fluorescent light emitted from fluorescent dye solution introduced in a posterior chamber. A coaxial phacoemulsification procedure was simulated with standard size (standard coaxial phacoemulsification) and smaller (micro coaxial phacoemulsification) surgical instruments. In both cases, an asymmetric flow rate of irrigation was observed, although both irrigation ports had the same dimensions prior to insertion into the eye. In cases where the tip of the handpiece was placed farther away from the top of the cornea, i.e., closer to the crystalline lens, direct impingement of irrigation flow onto the cornea surface was avoided and the flow turned back toward the handpiece along the surface of the corneal endothelium. Viscous shear stress on the corneal endothelium was computed based on the measured mean velocity distribution. The maximum shear stress for most cases exceeded 0.1 Pa, which is comparable to the shear stress that caused detachment of the corneal endothelial cells reported by Kaji et al. in Cornea 24:S55-S58, (2005). When direct impingement of the irrigation flow was avoided, the shear stress was reduced considerably.

  3. Elasticity of the eye's crystalline lens: A Brillouin light scattering study.

    Science.gov (United States)

    Bailey, S.; Gump, J.; Sooryakumar, R.; Jayaprakash, C.; Venkiteshwar, M. S.; Bullimore, M.; Twa, M.

    2009-03-01

    Focusing the eye on a near object results in an increase in its optical power brought about by contraction of the ciliary muscles and an increase in the lens surface curvature. Distant vision occurs when the muscular force flattens the lens. Central to the ability of the lens to alter shape are its mechanical properties. Thus, given that hardening of the lens would impede deformation and reduce its ability to undergo the changes required for accommodation, a noninvasive approach to measure the elastic properties of the lens is valuable. We present results of Brillouin scattering from bovine and human lenses (from the organ donor program at The Ohio State University) that measure their high frequency acoustic response. These measurements are conducted with a few milli-watts of laser power and, in the case of bovine lenses, from entire intact eye globes, allow the stiffness of the lens to be mapped across its cross-section. The results will be compared to values of the shear- and bulk-moduli determined from other techniques and the implications of differences in these moduli discussed.

  4. The Regularized Fast Hartley Transform Optimal Formulation of Real-Data Fast Fourier Transform for Silicon-Based Implementation in Resource-Constrained Environments

    CERN Document Server

    Jones, Keith

    2010-01-01

    The Regularized Fast Hartley Transform provides the reader with the tools necessary to both understand the proposed new formulation and to implement simple design variations that offer clear implementational advantages, both practical and theoretical, over more conventional complex-data solutions to the problem. The highly-parallel formulation described is shown to lead to scalable and device-independent solutions to the latency-constrained version of the problem which are able to optimize the use of the available silicon resources, and thus to maximize the achievable computational density, th

  5. Comparative Analyses of Phase Noise in 28 nm CMOS LC Oscillator Circuit Topologies: Hartley, Colpitts, and Common-Source Cross-Coupled Differential Pair

    Directory of Open Access Journals (Sweden)

    Ilias Chlis

    2014-01-01

    Full Text Available This paper reports comparative analyses of phase noise in Hartley, Colpitts, and common-source cross-coupled differential pair LC oscillator topologies in 28 nm CMOS technology. The impulse sensitivity function is used to carry out both qualitative and quantitative analyses of the phase noise exhibited by each circuit component in each circuit topology with oscillation frequency ranging from 1 to 100 GHz. The comparative analyses show the existence of four distinct frequency regions in which the three oscillator topologies rank unevenly in terms of best phase noise performance, due to the combined effects of device noise and circuit node sensitivity.

  6. Comparative analyses of phase noise in 28 nm CMOS LC oscillator circuit topologies: Hartley, Colpitts, and common-source cross-coupled differential pair.

    Science.gov (United States)

    Chlis, Ilias; Pepe, Domenico; Zito, Domenico

    2014-01-01

    This paper reports comparative analyses of phase noise in Hartley, Colpitts, and common-source cross-coupled differential pair LC oscillator topologies in 28 nm CMOS technology. The impulse sensitivity function is used to carry out both qualitative and quantitative analyses of the phase noise exhibited by each circuit component in each circuit topology with oscillation frequency ranging from 1 to 100 GHz. The comparative analyses show the existence of four distinct frequency regions in which the three oscillator topologies rank unevenly in terms of best phase noise performance, due to the combined effects of device noise and circuit node sensitivity.

  7. A randomized, multicenter phase 3 study comparing 2% rebamipide (OPC-12759) with 0.1% sodium hyaluronate in the treatment of dry eye.

    Science.gov (United States)

    Kinoshita, Shigeru; Oshiden, Kazuhide; Awamura, Saki; Suzuki, Hiroyuki; Nakamichi, Norihiro; Yokoi, Norihiko

    2013-06-01

    To investigate the efficacy of 2% rebamipide ophthalmic suspension compared with 0.1% sodium hyaluronate ophthalmic solution for the treatment of patients with dry eye. Randomized, multicenter, active-controlled parallel-group study. One hundred eighty-eight patients with dry eye. Following a 2-week screening period, patients were allocated randomly to receive 2% rebamipide or 0.1% sodium hyaluronate, administered as 1 drop in each eye 4 or 6 times daily, respectively, for 4 weeks. There were 2 primary end points: changes in the fluorescein corneal staining (FCS) score to determine noninferiority of 2% rebamipide and changes in the lissamine green conjunctival staining (LGCS) score to determine superiority. Secondary objective end points were Schirmer's test results and tear film breakup time (TBUT). Secondary subjective end points were dry eye-related ocular symptoms (foreign body sensation, dryness, photophobia, eye pain, and blurred vision) score and the patients' overall treatment impression score. In the primary analysis, the mean change from baseline in FCS scores verified noninferiority, indicated significant improvement, and, in LGCS scores, verified the superiority of 2% rebamipide to 0.1% sodium hyaluronate. Values for the Schirmer's test and TBUT were comparable between the 2 groups. For 2 dry eye-related ocular symptoms--foreign body sensation and eye pain--2% rebamipide showed significant improvements over 0.1% sodium hyaluronate. Patients had a significantly more favorable impression of 2% rebamipide than of 0.1% sodium hyaluronate; 64.5% rated treatment as improved or markedly improved versus 34.7%, respectively. No serious adverse events were observed. Administration of 2% rebamipide was effective in improving both the objective signs and subjective symptoms of dry eye. Those findings, in addition to the well-tolerated profile of 2% rebamipide, clearly show that it is an effective therapeutic method for dry eye. Proprietary or commercial disclosure

  8. Influence on ocular surface after cataract surgery and effect of topical diquafosol on postoperative dry eye: a multicenter prospective randomized study

    Science.gov (United States)

    Miyake, Kensaku; Yokoi, Norihiko

    2017-01-01

    Purpose To investigate influences of 3% diquafosol sodium ophthalmic solution (DQS) on ocular surface after cataract surgery and effects on postoperative dry eye. Design This study had two consecutive prospective study phases. The former was an observational study from before cataract surgery to 4 weeks after surgery and the latter was a randomized open-label study from 4 to 8 weeks after surgery. Methods Subjects were 433 eyes of 433 patients undergoing cataract surgery with intraocular lens implantation. Dry eye examination of tear breakup time (BUT), corneal and conjunctival fluorescein staining scores, total subjective symptom score (12 symptoms), and Schirmer I test were conducted before surgery and 4 weeks after surgery. Patient demographics and these examination results were used to analyze risk factors to predict postoperative dry eye. In a randomized study, 154 eyes diagnosed with dry eye postoperatively were applied either DQS or artificial tears (AT) six times daily for 4 weeks. The data of the examinations were compared. Results At 4 weeks after surgery, BUT was shortened significantly (P=0.036), fluorescein staining score increased significantly (P=0.012), but total subjective symptom score was significantly improved (Pscore was significantly improved in both groups (Pscore was significantly decreased in the AT group (Pfilm stability and ocular surface, and DQS has a capability to improve them. PMID:28360509

  9. Development of the conceptual framework for the Eye-Drop Satisfaction Questionnaire (EDSQ© in glaucoma using a qualitative study

    Directory of Open Access Journals (Sweden)

    Trudeau Elyse

    2007-08-01

    Full Text Available Abstract Background Compliance is a major issue in glaucoma care. It is usually poor in glaucomatous patients, and may ultimately result in an acceleration of the disease progression and a risk of blindness. Reasons for this poor compliance are complex and multifactorial, amongst which patient satisfaction can be counted. The objective of this study was to develop a questionnaire to assess patient satisfaction and compliance with eye-drop treatment. Methods A qualitative study was carried out to develop the questionnaire. An interview guide was developed based on a literature review. Structured interviews of fifteen French and English patients with primary open-angle glaucoma or intraocular hypertension were conducted by trained interviewers of the native language of the interviewees. General concepts and subconcepts were identified from the transcripts. The questionnaire was developed using the patient verbatim, and submitted to six patients (French and English for cognitive debriefing. Following patients' comments, items were modified and restructured, and a pilot questionnaire was designed. Results Analysis of data from the interviews with patients and clinicians resulted in the elicitation of concepts related to patient satisfaction and compliance with glaucomatous treatment. These were further refined and used to generate a test questionnaire, which consisted of 46 items grouped into 6 domains: patient characteristics, treatment characteristics, patient-clinician relationship, patient experience with the disease and the treatment, interaction between the patient and the treatment, and patient knowledge of the disease and the treatment. Conclusion The Eye-Drop Satisfaction Questionnaire (EDSQ conceptual framework and items were developed simultaneously in French and in English. This questionnaire could be used to evaluate patient satisfaction and compliance with eye-drop treatment and would facilitate the identification of patients at risk

  10. Relationship between Refractive Error and Ocular Biomet-rics in Twin Children:the Guangzhou Twin Eye Study

    Institute of Scientific and Technical Information of China (English)

    Decai Wang; Bin Liu; Shengsong Huang; Wenyong Huang; Mingguang He

    2014-01-01

    Purpose:.A cross-sectional study was conducted to explore the relationship between refractive error and ocular biometrics in children from the Guangzhou twin eye study.Methods:.Twin participants aged 7-15 years were selected from Guangzhou Twin Eye Study..Ocular examinations included vi-sual acuity measurement, ocular motility evaluation, autore-fraction under cycloplegia, and anterior segment, media, and fundus examination...Axial length (AL),..anterior cham ber depth (ACD), and corneal curvature radius were measured us-ing partial coherence laser interferometry. A multivariate linear regression model was used for statistical analysis.Results:.Twin children from Guangzhou city showed a de-creased spherical equivalent with age,.whereas both AL and ACD were increased and corneal curvature radius remained unchanged. When adjusted by age and gender, the data from 77% of twins presenting with spherical equivalent changes in-dicated that these were caused by predictable variables. (R2=0.77, P<0.001). Primary factors affecting children's refraction included axial length (β=-0.97,P<0.001), ACD (β=0.33,P<0.001), and curvature radius (β=2.10,P<0.001). Girls had a higher tendency for myopic status than did boys (β=-0.26,P<0.001)..Age exerted no effect upon the changes in refraction (β=-0.01, P=0.25).Conclusion:.Refraction is correlated with ocular biometrics. Refractive status is largely determined by axial length as the major factor. (Eye Science 2014; 29:129-133)

  11. Eye Contricks

    Directory of Open Access Journals (Sweden)

    Nicholas J Wade

    2011-06-01

    Full Text Available Pictorial images are icons as well as eye-cons: they provide distillations of objects or ideas into simpler shapes. They create the impression of representing that which cannot be presented. Even at the level of the photograph, the links between icon and object are tenuous. The dimensions of depth and motion are missing from icons, and these alone introduce all manner of potential ambiguities. The history of art can be considered as exploring the missing link between icon and object. Eye-cons can also be illusions—tricks of vision so that what is seen does not necessarily correspond to what is physically presented. Pictorial images can be spatialised or stylised; spatialised images generally share some of the projective characteristics of the object represented. Written words are also icons, but they do not resemble the objects they represent—they are stylised or conventional. Icons as stylised words and spatialised images were set in delightful opposition by René Magritte in a series of pipe paintings, and this theme is here alluded to. Most of visual science is now concerned with icons—two-dimensional displays on computer monitors. Is vision now the science of eye-cons?

  12. "I kissed a girl and I liked it": an eye-tracking study of women's sexual fluidity

    OpenAIRE

    Wesson, Charlotte

    2015-01-01

    Heterosexual women’s sexuality differs from men’s as it is seen as more ‘fluid’ (Baumeister, 2000). One explanation of this is that men attend to the gender of stimuli, whereas women attend to the sexuality, with sexual activity in the stimulus a stronger determinant of women’s sexual response (Chivers, et al., 2007). The present study aimed to further investigate whether women’s sexuality is more fluid by looking at the abovementioned claim. Eye-tracking and self-repor...

  13. Second-phase validation study of short time exposure test for assessment of eye irritation potency of chemicals.

    Science.gov (United States)

    Kojima, Hajime; Hayashi, Kazuhiko; Sakaguchi, Hitoshi; Omori, Takashi; Otoizumi, Takuya; Sozu, Takashi; Kuwahara, Hirofumi; Hayashi, Takumi; Sakaguchi, Mayumi; Toyoda, Akemi; Goto, Haruka; Watanabe, Shinichi; Ahiko, Kyoko; Nakamura, Tsuneaki; Morimoto, Takashi

    2013-09-01

    A Short Time Exposure (STE) test is a cytotoxicity test that uses SIRC cells (rabbit corneal cell line) to assess eye irritation potency following a 5-min chemical exposure. This second-phase validation study assessed the predictive capacity of the STE test using 40 coded test substances at three laboratories. A Validation Management Team (VMT) then evaluated the predictivity of the STE test for United Nation (UN) Globally Harmonized System (GHS) categories using 63 test substances including the results of the first-phase validation study. The STE test can assess not only the severe or corrosive ocular irritants (corresponding to the UN GHS Category 1) but also non-irritant (corresponding to UN GHS Non Category) from other toxicity classes, especially for limited types of test substances. The predictivity by STE test, however, was insufficient for identification of UN GHS categories (Category 1, Category 2, or Non Category). These results suggest that the STE test can be recommended as an initial step in a top-down approach to identification of severe irritants and test substances that require classification for eye irritation (UN GHS Category 1) as well as an initial step in a bottom-up approach to identification of test substances that do not require classification for eye irritation (UN GHS Non Category) from other toxicity classes, especially for limited types of test substances. On the other hand, the STE test is not considered adequate for the identification of mild or moderate irritants (i.e., UN GHS Categories 2A and 2B) and severe irritants (UN GHS Category 1).

  14. The eye drop chart: a pilot study for improving administration of and compliance with topical treatments in glaucoma patients

    Directory of Open Access Journals (Sweden)

    McVeigh KA

    2015-05-01

    Full Text Available Katherine Anne McVeigh,1 Georgios Vakros21Department of Ophthalmology, Royal United Hospital, Combe Park, Bath, UK; 2Department of Ophthalmology, Queen’s Hospital, Romford, Essex, UKAim: In order to improve patient education, compliance, and administration of eye drops prescribed for patients suffering with glaucoma within a UK ophthalmology department, an eye drop chart (EDC was designed, developed, and piloted with patients attending the glaucoma clinic over 1 month.Methods: A cross-sectional prospective pilot study of 25 patients using an administration aid and a self-reported questionnaire. Chi-square tests were used to compare responses pre- and postintervention.Results: Results demonstrated an impressive improvement in nine of eleven categories assessed regarding drop administration and compliance. Patients stating that they always wash their hands increased significantly from 64% (13 participants to 92% (23 participants (P=0.029, and those who always shake the bottle improved from 40% (10 to 84% (21 (P=0.001. Punctal occlusion techniques improved from 44% (11 to 72% (18 (P=0.015. Finally, patients who always discarded the bottle after 28 days of use rose from 68% to 92%, though the difference was not significant (P=0.09. Only the number of drops being administered to the eye and the length of time left between the application of drops remained relatively unchanged. Sixty-four percent reported finding EDC helpful or useful, 52% had positive responses when asked if they would continue using EDC, and 88% would recommend it to a friend.Conclusion: Although there are limitations to the data as they are subjective, descriptive, and limited to sample size of 25, the results of this pilot study have shown promise. The EDC appears to be a cost-effective way at improving patients’ use of topical ocular medications.Keywords: glaucoma, administration, compliance, aid, drop chart

  15. Five-Year Incidence of Visual Impairment in Middle-Aged Iranians: The Shahroud Eye Cohort Study.

    Science.gov (United States)

    Hashemi, Hassan; Mehravaran, Shiva; Emamian, Mohammad Hassan; Fotouhi, Akbar

    2017-02-01

    To study the 5-year incidence of visual impairment and its causes and risk factors, in the middle-aged Iranian sample of the Shahroud Eye Cohort Study (ShECS). Data from subjects who had participated in both phases of the ShECS were used to determine age- and sex-specific incidence rates of visual impairment using the World Health Organization (WHO) definitions for bilateral low vision (visual acuity, VA, >0.5 and ≤1.3 LogMAR in the better eye) and blindness (VA worse than 1.3 LogMAR in the better eye). Risk ratios (RR) and 95% confidence intervals (CIs) were calculated using multivariable log-binomial regression. Of the 5079 ShECS I survivors, 4737 (93.3%) completed the 5-year follow-up. Their mean age at baseline was 50.9 ± 6.2 years, and 58.9% were female. The incidence of visual impairment was 1.12% (95% CI 0.82-1.42%) by presenting VA and 0.19% (95% CI 0.07-0.32%) by best-corrected VA; leading causes of the former were uncorrected refractive error (81.3%) and diabetic retinopathy (15.1%). In the multivariable model, risk factors for incident visual impairment by presenting VA were older age (RR 1.05, p = 0.044), lower education (RR 0.89, p = 0.002), and diabetes (RR 3.74, p visual impairment in a middle-aged Iranian population. Since age is a major risk factor, the number of visually impaired is expected to increase as the population ages, and less treatable causes such as diabetic retinopathy begin to surface. Measures for tackling uncorrected refractive error and enhancing diabetes screening and preventive programs are recommended.

  16. Marek's disease virus infection in the eye: chronological study of the lesions, virus replication, and vaccine-induced protection.

    Science.gov (United States)

    Pandiri, Arun K R; Cortes, Aneg L; Lee, Lucy F; Gimeno, I M

    2008-12-01

    Marek's disease virus (MDV) infection in the eye was studied chronologically after inoculating 1-day-old chickens with a very virulent MDV strain, Md5. The ocular lesions could be classified as early lesions (6-11 days postinoculation [dpi]) and late lesions (26 and 56 dpi), based upon the location and severity of the lesions. The early lesions involved iris, ciliary body, and choroid layer, and were characterized by endothelial cell hypertrophy, vasculitis, and infiltration of lymphocytes (mainly CD8+), plasma cells, macrophages, and heterophils. Expression of early MDV-antigen pp38 in the cells infiltrating choroid layer was detected as early as 11 dpi. Late lesions consisted of severe lymphohistiocytic uveitis, keratitis, pectenitis, vitreitis, retinitis, and segmental to diffuse retinal necrosis. Cell infiltration included macrophages, granulocytes, plasma cells, and both CD4+ and CD8+ cells of various sizes. Expression of early MDV-antigen pp38 was readily found within the retina, uveal tract, and corneal epithelium. No expression of late-antigen gB or oncoprotein meq was detected in any of the eyes examined. A second experiment was conducted to study the effect of vaccination on the development of ocular lesions. Both HVT and CVI988 were able to protect against the development of early ocular lesions in chickens infected with very virulent plus strain MDV 648A. However, only CVI988 conferred complete protection against the development of late ocular lesions. HVT conferred partial protection, as it reduced the frequency and severity of the late ocular lesions. These results enhance our understanding of the nature and pattern of MDV infection in the eye.

  17. About the effect of eye blinking on drug release from pHEMA-based hydrogels: an in vitro study.

    Science.gov (United States)

    Galante, R; Paradiso, P; Moutinho, M G; Fernandes, A I; Mata, J L G; Matos, A P A; Colaço, R; Saramago, B; Serro, A P

    2015-01-01

    The development of new ophthalmic drug delivery systems capable of increasing the residence time of drugs in the eye and improve its bioavailability relatively to eyedrops has been object of intense research in recent years. Several studies have shown that drug-loaded therapeutic soft contact lenses (SCLs) constitute a promising approach, with several potential advantages as compared with collyria. The main objective of this work is to study the effect of repetitive load and friction cycles caused by the eye blinking, on the drug release from hydrogels used in SCLs which, as far as we know, was never investigated before. Two poly-2-hydroxyethylmethacrylate-based hydrogels, pHEMA-T and pHEMA-UV, were used as model materials. Levofloxaxin was chosen as model drug. The hydrogels were fully characterized in what concerns structural and physicochemical properties. pHEMA-UV revealed some superficial porosity and a lower short-range order than pHEMA-T. We observe that the load and friction cycles enhanced the drug release from pHEMA-UV hydrogels. The application of a simple mathematical model, which takes into account the drug dilution caused by the tear flow, showed that the enhancement of the drug release caused by blinking on this hydrogel may be relevant in in vivo conditions. Conversely, the more sustained drug release from pHEMA-T is not affected by load and friction cycles. The conclusion is that, depending on the physicochemical and microstructural characteristics of the hydrogels, blinking is a factor that may affect the amount of drug delivered to the eye by SCLs and should thus be considered.

  18. Development of an Arabic version of the National Eye Institute Visual Function Questionnaire as a tool to study eye diseases patients in Egypt

    Institute of Scientific and Technical Information of China (English)

    Nizar; Saleh; Abdelfattah; Mohamed; Amgad; Ahmed; A; Salama; Marina; E; Israel; Ghada; A; Elhawary; Ahmed; E; Radwan; Mohamed; M; Elgayar; Tamer; M; EL; Nakhal; Islam; T; Elkhateb; Heba; A; Hashem; Doha; K; Embaby; Amira; A; Elabd; Reem; K; Elwy; Magdi; S; Yacoub; Hamdy; Salem; Mohamed; Abdel-Baqy; Ahmad; Kassem

    2014-01-01

    AIM:To develop and test an Arabic version of the National Eye Institute Visual Function Questionnaire-25(NEI-VFQ-25).METHODS:NEI-VFQ-25 was translated into Arabic according to WHO translation guidelines. We enrolled adult consenting patients with bilateral chronic eye diseases who presented to 14 hospitals across Egypt from October to December 2012, and documented their clinical findings. Psychometric properties were then tested using STATA.RESULTS:We recruited 379 patients, whose mean age was(54.5±15)y. Of 46.2% were males, 227 had cataract,31 had glaucoma, 23 had retinal detachment, 37 had diabetic retinopathy, and 61 had miscellaneous visual defects. Non-response rate and the floor and ceiling numbers of the Arabic version(ARB-VFQ-25) were calculated. Internal consistency was high in all subscales(except general health), with Cronbach-α ranging from0.702-0.911. Test-retest reliability was high(intraclass correlation coefficient 0.79).CONCLUSION:RB-VFQ-25 isareliableandvalidtool for assessing visual functions of Arabic speaking patients. However, some questions had high non-response rates and should be substituted by available alternatives. Our results support the importance of including self-reported visual functions as part of routine ophthalmologic examination.

  19. Central corneal thickness and its association with ocular and general parameters in Indians: the Central India Eye and Medical Study.

    Science.gov (United States)

    Nangia, Vinay; Jonas, Jost B; Sinha, Ajit; Matin, Arshia; Kulkarni, Maithili

    2010-04-01

    To evaluate the distribution of central corneal thickness (CCT) and its associations in an adult Indian population. Population-based study. The Central India Eye and Medical Study is a population-based study performed in a rural region close to Nagpur in Central India; it included 4711 subjects (ages 30+ years) of 5885 eligible subjects (response rate, 80.1%). The participants underwent a detailed ophthalmic and medical examination, including 200 standardized questions on socioeconomic background, lifestyle, social relations, and psychiatric depression. This study was focused on CCT as measured by sonography and its associations. Intraocular pressure was measured by applanation tonometry. Central corneal thickness and intraocular pressure. Central corneal thickness measurement data were available on 9370 (99.4%) eyes. Mean CCT was 514+/-33 microm (median, 517 microm; range, 290-696 microm). By multiple regression analysis, CCT was associated significantly with younger age (Peyes with a corneal refractive power of 45 or more diopters were excluded, the relationship between CCT and axial length was no longer statistically significant (P>0.05), whereas all other relationships remained significant. Intraocular pressure readings increased significantly (Peyes that had thick corneas or steep corneas. Central corneal thickness and steepness of the anterior corneal surface may thus both have to be taken into account when applanation tonometry is performed. The author(s) have no proprietary or commercial interest in any materials discussed in this article. Copyright 2010 American Academy of Ophthalmology. Published by Elsevier Inc. All rights reserved.

  20. Efficacy of an Amblyopia Treatment Program with Both Eyes Open: A Functional Near-Infrared Spectroscopy Study.

    Science.gov (United States)

    Iwata, Yo; Handa, Tomoya; Ishikawa, Hitoshi; Shoji, Nobuyuki; Shimizu, Kimiya

    2016-01-01

    To investigate the efficacy of an amblyopia treatment program with both eyes open. Ten subjects (mean age 20.5 ± 1.5 years) were enrolled. All subjects had un-remarkable ophthalmic examinations, but several subjects had minor refractive errors. Vision function was evaluated using the 3-D visual function trainer-ORTe. Brain measurements were made using functional near-infrared spectroscopy (fNIRS) to examine the oxygenated hemoglobin (HbO2) concentration change upon visual stimulus presentation. The three conditions were as follows: both eyes open and both eyes stimulated, both eyes open and only one eye stimulated, and one eye open and one eye stimulated. Changes in HbO2 between the rest and stimulation phases were not statistically different between the unilateral and bilateral stimulation conditions with both eyes open. However, HbO2 change was significantly higher in subjects with both eyes open than in subjects with one eye closed (P amblyopia treatment administered without occluding the healthy eye may provide the greatest therapeutic benefit. © 2016 Board of regents of the University of Wisconsin System, American Orthoptic Journal, Volume 66, 2016, ISSN 0065-955X, E-ISSN 1553-4448.

  1. Study on algorithm of dynamic uncalibrated eye-in-hand visual servoing system

    Institute of Scientific and Technical Information of China (English)

    2007-01-01

    Currently, most visual servoing system must be calibrated, while it is impossible to calibrate cameras and robot models precisely in industrial practice, so a novel dynamic uncalibrated eye-in-hand visual servoing system of tracking a moving target is proposed. The method does not require calibration of camera and robot kinematic models. Vision guided algorithm for tracking dynamic image is developed through minimizing nonlinear objective function. For the large residual has not been approximated in dynamic environment and the change of composite image Jacobian with time increment has not been computed in visual servoing system now,large residuals are dynamic approximated and the change of composite image Jacobian at each iterative step is computed.Simulation results demonstrate the validity of these approaches.

  2. Sources of variation in developmental language disorders: evidence from eye-tracking studies of sentence production.

    Science.gov (United States)

    Norbury, Courtenay Frazier

    2014-01-01

    Skilled sentence production involves distinct stages of message conceptualization (deciding what to talk about) and message formulation (deciding how to talk about it). Eye-movement paradigms provide a mechanism for observing how speakers accomplish these aspects of production in real time. These methods have recently been applied to children with autism spectrum disorder (ASD) and specific language impairment (LI) in an effort to reveal qualitative differences between groups in sentence production processes. Findings support a multiple-deficit account in which language production is influenced not only by lexical and syntactic constraints, but also by variation in attention control, inhibition and social competence. Thus, children with ASD are especially vulnerable to atypical patterns of visual inspection and verbal utterance. The potential to influence attentional focus and prime appropriate language structures are considered as a mechanism for facilitating language adaptation and learning.

  3. Atmospheric studies using the high-resolution fly's eye xenon flasher array

    Science.gov (United States)

    Wiencke, Lawrence R.; Bird, D. J.; Chen, G. F.; Clay, R. W.; Dai, H. Y.; Dawson, B. R.; Huang, M. A.; Jui, C. C. H.; Kidd, M. J.; Kieda, D. B.; Ko, S.; Larsen, C. G.; Loh, Eugene C.; Smith, J. D.; Sokolsky, Pierre; Sommers, Paul; Tang, J. K.; Thomas, Stan B.; Wilkinson, C. R.; Yoshida, S.

    1996-11-01

    The High Resolution Fly's Eye (HiRes) cosmic ray detector at Dugway Utah, measures UV scintillation light from extensive air showers. The detection technique is calorimetric in that the amount of light produced is proportional to the energy of the primary particle. Primary particle energies range from 1017 to more than 1020 electron volts. The detector can measure air showers more than 30 km away, a distance of several atmospheric extinction lengths. Variations in the atmosphere can cause significant variations in the amount of light reaching the detector. Atmospheric monitoring is extremely important. This paper discusses a method, under development, that uses the HiRes detector to measure light scattered from pulsed collimated xenon flashbulb sources (Flashers). Discussion includes a description of the light sources and a preliminary data analysis to extract a measurement of atmospheric extinction length and scale height.

  4. Capabilities of the bathymetric Hawk Eye LiDAR for coastal habitat mapping: A case study within a Basque estuary

    Science.gov (United States)

    Chust, Guillem; Grande, Maitane; Galparsoro, Ibon; Uriarte, Adolfo; Borja, Ángel

    2010-10-01

    The bathymetric LiDAR system is an airborne laser that detects sea bottom at high vertical and horizontal resolutions in shallow coastal waters. This study assesses the capabilities of the airborne bathymetric LiDAR sensor (Hawk Eye system) for coastal habitat mapping in the Oka estuary (within the Biosphere Reserve of Urdaibai, SE Bay of Biscay, northern Spain), where water conditions are moderately turbid. Three specific objectives were addressed: 1) to assess the data quality of the Hawk Eye LiDAR, both for terrestrial and subtidal zones, in terms of height measurement density, coverage, and vertical accuracy; 2) to compare bathymetric LiDAR with a ship-borne multibeam echosounder (MBES) for different bottom types and depth ranges; and 3) to test the discrimination potential of LiDAR height and reflectance information, together with multi-spectral imagery (three visible and near infrared bands), for the classification of 22 salt marsh and rocky shore habitats, covering supralittoral, intertidal and subtidal zones. The bathymetric LiDAR Hawk Eye data enabled the generation of a digital elevation model (DEM) of the Oka estuary, at 2 m of horizontal spatial resolution in the terrestrial zone (with a vertical accuracy of 0.15 m) and at 4 m within the subtidal, extending a water depth of 21 m. Data gaps occurred in 14.4% of the area surveyed with the LiDAR (13.69 km 2). Comparison of the LiDAR system and the MBES showed no significant mean difference in depth. However, the Root Mean Square error of the former was high (0.84 m), especially concentrated upon rocky (0.55-1.77 m) rather than in sediment bottoms (0.38-0.62 m). The potential of LiDAR topographic variables and reflectance alone for discriminating 15 intertidal and submerged habitats was low (with overall classification accuracy between 52.4 and 65.4%). In particular, reflectance retrieved for this case study has been found to be not particularly useful for classification purposes. The combination of the Li

  5. Prospective randomized study of clinical performance of 3 aspheric and 2 spherical intraocular lenses in 250 eyes.

    Science.gov (United States)

    Caporossi, Aldo; Martone, Gianluca; Casprini, Fabrizio; Rapisarda, Lorenzo

    2007-09-01

    To compare the quality of vision with aspheric and spherical intraocular lenses (IOLs) in pseudophakic patients. This prospective, comparative, randomized study included 250 eyes of 125 patients with bilateral cataracts. Patients were randomly assigned to receive either IOLs with a spherical biconvex optic (Acrysof SN6OAT [Alcon] or Sensar AR40e [Advanced Medical Optics, AMO]) or IOLs with an aspheric optic (Acrysof IQ SN6OWF [Alcon], Tecnis Z9000 [AMO], or Sofport L161AO [Bausch & Lomb]). Ophthalmologic examination including best spectacle-corrected visual acuity, pupil size, ocular dominance investigation, contrast sensitivity under mesopic and photopic conditions, and wavefront analysis was performed 2 months postoperatively. Aspheric IOLs showed better contrast sensitivity compared to spherical IOLs at spatial frequencies of 6, 12, and 18 cycles per degree (cpd) under photopic conditions and at all spatial frequencies under mesopic conditions. There was no significant difference among the three aspheric IOLs at all spatial frequencies under either photopic or mesopic conditions. Mean total spherical aberration was statistically lower in dominant eyes with aspheric IOLs (0.05 +/- 0.06, 0.11 +/- 0.1, and 0.19 +/- 0.08 pm for the Tecnis Z9000, Acrysof IQ SN6OWF, and Sofport L161AO, respectively) compared with eyes with spherical IOLs (0.62 +/- 0.24 and 0.46 +/- 0.19 microm for the Acrysof SN6OAT and Sensar AR40e, respectively) for a 5-mm pupil diameter. The aspheric IOLs had less wavefront aberrations and performed better under both photopic and mesopic contrast sensitivity compared to the spherical IOLs. These findings confirm it is possible to improve the optical performance of IOLs by modifying the surfaces.

  6. Long-term results of riboflavin ultraviolet a corneal collagen cross-linking for keratoconus in Italy: the Siena eye cross study.

    Science.gov (United States)

    Caporossi, Aldo; Mazzotta, Cosimo; Baiocchi, Stefano; Caporossi, Tomaso

    2010-04-01

    To report the long-term results of 44 keratoconic eyes treated by combined riboflavin ultraviolet A collagen cross-linking in the first Italian open, nonrandomized phase II clinical trial, the Siena Eye Cross Study. Perspective, nonrandomized, open trial. After Siena University Institutional Review Board approval, from September 2004 through September 2008, 363 eyes with progressive keratoconus were treated with riboflavin ultraviolet A collagen cross-linking. Forty-four eyes with a minimum follow-up of 48 months (mean, 52.4 months; range, 48 to 60 months) were evaluated before and after surgery. Examinations comprised uncorrected visual acuity, best spectacle-corrected visual acuity, spherical spectacle-corrected visual acuity, endothelial cells count (I Konan, Non Con Robo; Konan Medical, Inc., Hyogo, Japan), optical (Visante OCT; Zeiss, Jena, Germany) and ultrasound (DGH; Pachette, Exton, Pennsylvania, USA) pachymetry, corneal topography and surface aberrometry (CSO EyeTop, Florence, Italy), tomography (Orbscan IIz; Bausch & Lomb Inc., Rochester, New York, USA), posterior segment optical coherence tomography (Stratus OCT; Zeiss, Jena, Germany), and in vivo confocal microscopy (HRT II; Heidelberg Engineering, Rostock, Germany). Keratoconus stability was detected in 44 eyes after 48 months of minimum follow-up; fellow eyes showed a mean progression of 1.5 diopters in more than 65% after 24 months, then were treated. The mean K value was reduced by a mean of 2 diopters, and coma aberration reduction with corneal symmetry improvement was observed in more than 85%. The mean best spectacle-corrected visual acuity improved by 1.9 Snellen lines, and the uncorrected visual acuity improved by 2.7 Snellen lines. The results of the Siena Eye Cross Study showed a long-term stability of keratoconus after cross-linking without relevant side effects. The uncorrected visual acuity and best spectacle-corrected visual acuity improvements were supported by clinical, topographic

  7. Dietary Supplementation with a Combination of Lactoferrin, Fish Oil, and Enterococcus faecium WB2000 for Treating Dry Eye: A Rat Model and Human Clinical Study.

    Science.gov (United States)

    Kawashima, Motoko; Nakamura, Shigeru; Izuta, Yusuke; Inoue, Sachiko; Tsubota, Kazuo

    2016-04-01

    To examine the effect of a combined dietary supplement containing fish oil, lactoferrin, zinc, vitamin C, lutein, vitamin E, γ-aminobutanoic acid, and Enterococcus faecium WB2000 on dry eye. A preliminary study in a rat model and a prospective, randomized, double-blind, placebo-controlled study in humans were conducted. Forty Japanese volunteers aged 22 to 59 years were randomized into combined dietary supplement (2 capsules/day; 20 participants) and placebo (vehicle; 19 participants) groups and treated once daily for 8 weeks. Rats received the combined dietary supplement components (10 or 50 mg/kg orally) or vehicle (2% DMSO), and dry eye was mechanically induced for 2 days. Tear production was measured in rats after dry eye was induced. Humans were assessed at baseline and weeks 4 and 8 post-supplementation based on keratoconjunctival epithelial damage; fluorescein tear film breakup time; tear production; biochemical data; information regarding subjective dry eye symptoms by answering a questionnaire; and information regarding adverse events via medical interviews. Supplementation dose-dependently mitigated the decrease in tear production in rats. Among subjects with confirmed dry eye, clinical symptoms improved at weeks 4 and 8 more significantly in the supplementation group than in the placebo group (P<.05). The rate of increase in the Schirmer value was greater in the supplementation group. No adverse events occurred. Supplementation improved objective and subjective dry eye symptoms. Copyright © 2016 Elsevier Inc. All rights reserved.

  8. A study to assess the feasibility of undertaking a randomized controlled trial of adherence with eye drops in glaucoma patients

    Directory of Open Access Journals (Sweden)

    Richardson C

    2013-10-01

    Full Text Available Cliff Richardson,1 Lisa Brunton,1 Nicola Olleveant,1 David B Henson,1 Mark Pilling,1 Jane Mottershead,2 Cecilia H Fenerty,2 Anne Fiona Spencer,2 Heather Waterman1 1School of Nursing, Midwifery and Social Work, University of Manchester, 2Royal Manchester Eye Hospital, Central Manchester Foundation Trust, Manchester, United Kingdom Background: Adherence with therapy could influence the progression of glaucoma and ultimately affect the onset of visual impairment in some individuals. This feasibility study evaluated the measures to be used for a future randomized controlled trial assessing the effects of group-based education on adherence with eye drops. Methods: People diagnosed with glaucoma within the previous 12 months attending a regional ophthalmology clinic in the North West of England were recruited. A two-session education program delivered one week apart had been devised as part of a previous project. A combined adult learning and health needs approach to education was taken. Outcomes measured were knowledge of glaucoma, self-report of adherence, illness perception, beliefs about medicines, patient enablement, and general health (Short Form-12. Adherence was also measured objectively using a Medical Events Monitoring System device. Results: Twenty-six participants consented to undertake the educational program and 19 produced analyzable data. Knowledge of glaucoma, illness perception, beliefs about medicine, and patient enablement all showed statistically significant improvements after education. Mean adherence with eye drops was maintained above 85% before and for 3 months after attendance at the educational program. Self-report exaggerated adherence by at least 10% when compared with the objective Medical Events Monitoring System data, and in fact the kappa agreement was zero. Conclusion: All questionnaires other than the Short Form-12 were considered to be valuable measures and use of a Medical Events Monitoring System device was

  9. Lifitegrast ophthalmic solution 5.0% for treatment of dry eye disease: results of the OPUS-1 phase 3 study.

    Science.gov (United States)

    Sheppard, John D; Torkildsen, Gail L; Lonsdale, John D; D'Ambrosio, Francis A; McLaurin, Eugene B; Eiferman, Richard A; Kennedy, Kathryn S; Semba, Charles P

    2014-02-01

    To assess the efficacy and safety of lifitegrast ophthalmic solution 5.0% compared with placebo in subjects with dry eye disease. Prospective, randomized, double-masked, placebo-controlled, parallel arm, multicenter clinical trial. A total of 588 adult subjects with dry eye disease. Eligible subjects were randomized 1:1 to receive topically administered lifitegrast (5.0%) or placebo (vehicle) twice daily for 84 days after a 14-day open-label placebo run-in period. After enrollment (day 0), subjects were evaluated at days 14, 42, and 84. Key objective (fluorescein and lissamine staining scores [Ora scales]) and subjective (Ocular Surface Disease Index [OSDI], 7-item visual analog scale, and ocular discomfort score [Ora scale]) measures were assessed at all visits. The primary objective efficacy measure (sign) was mean change from baseline inferior corneal staining score (ICSS) at day 84. The co-primary subjective efficacy measure (symptom) was the mean change from baseline in the visual-related function subscale score of the Ocular Surface Disease Index (VR-OSDI). Supportive measures included corneal fluorescein scores (superior, central, total region) and conjunctival lissamine scores (nasal, temporal, total region) and symptom scores at day 84. The study met the primary objective efficacy ICSS end point in demonstrating superiority of lifitegrast compared with placebo (P = 0.0007). Lifitegrast significantly reduced corneal fluorescein staining (superior, P = 0.0392; total cornea, P = 0.0148) and conjunctival lissamine staining (nasal, P = 0.0039; total conjunctiva, P = 0.0086) at day 84 versus placebo. Significant (P measure (P = 0.7894). However, significant improvements were observed at day 84 in ocular discomfort (P = 0.0273) and eye dryness (P = 0.0291), the most common and severe symptoms reported at baseline in both groups. There were no unanticipated or serious ocular adverse events (AEs). The most frequent reported ocular AEs were transient intermittent

  10. Individual differences in smoking-related cue reactivity in smokers: an eye-tracking and fMRI study.

    Science.gov (United States)

    Kang, O-Seok; Chang, Dong-Seon; Jahng, Geon-Ho; Kim, Song-Yi; Kim, Hackjin; Kim, Jong-Woo; Chung, Sun-Yong; Yang, Seung-In; Park, Hi-Joon; Lee, Hyejung; Chae, Younbyoung

    2012-08-07

    Measures of cue reactivity provide a means of studying and understanding addictive behavior. We wanted to examine the relationship between different cue reactivity measures, such as attentional bias and subjective craving, and functional brain responses toward smoking-related cues in smokers. We used eye-tracking measurements, a questionnaire for smoking urges-brief and functional magnetic resonance imaging to assess the responses to smoking-related and neutral visual cues from 25 male smokers after 36 h of smoking abstinence. Regression analyses were conducted to determine the correlation between cue-evoked brain responses and the attentional bias to smoking-related cues. The eye gaze dwell time percentage was longer in response to smoking-related cues than neutral cues, indicating significant differences in attentional bias towards smoking-related cues. The attentional bias to smoking-related cues correlated with subjective craving ratings (r=0.660, psmoking-related cues, whereas the orbitofrontal cortex, the insula and the superior temporal gyrus were associated with smoking-related cue-induced craving and smoking urges. These results suggest that attentional mechanisms in combination with motivational and reward-related mechanisms play a role in smoking-related cue reactivity. We confirmed a positive correlation between different smoking-related cue reactivities, such as attentional bias and subjective craving, and functional brain responses in various individuals. Further studies in this field might contribute to a better individualized understanding of addictive behavior.

  11. Disentangling the initiation from the response in joint attention: an eye-tracking study in toddlers with autism spectrum disorders.

    Science.gov (United States)

    Billeci, L; Narzisi, A; Campatelli, G; Crifaci, G; Calderoni, S; Gagliano, A; Calzone, C; Colombi, C; Pioggia, G; Muratori, F

    2016-05-17

    Joint attention (JA), whose deficit is an early risk marker for autism spectrum disorder (ASD), has two dimensions: (1) responding to JA and (2) initiating JA. Eye-tracking technology has largely been used to investigate responding JA, but rarely to study initiating JA especially in young children with ASD. The aim of this study was to describe the differences in the visual patterns of toddlers with ASD and those with typical development (TD) during both responding JA and initiating JA tasks. Eye-tracking technology was used to monitor the gaze of 17 children with ASD and 15 age-matched children with TD during the presentation of short video sequences involving one responding JA and two initiating JA tasks (initiating JA-1 and initiating JA-2). Gaze accuracy, transitions and fixations were analyzed. No differences were found in the responding JA task between children with ASD and those with TD, whereas, in the initiating JA tasks, different patterns of fixation and transitions were shown between the groups. These results suggest that children with ASD and those with TD show different visual patterns when they are expected to initiate joint attention but not when they respond to joint attention. We hypothesized that differences in transitions and fixations are linked to ASD impairments in visual disengagement from face, in global scanning of the scene and in the ability to anticipate object's action.

  12. Eye Contricks

    Directory of Open Access Journals (Sweden)

    N Wade

    2011-04-01

    Full Text Available Icons are eye-cons: they provide a distillation of a complex object or idea into a simple pictorial shape. They create the impression of representing that which cannot be presented. Even at the level of the photograph, the links between icon and object are tenuous. The dimension of distance or depth is missing from the icon, and this alone introduces all manner of potential ambiguities. The history of art can be considered as an exploration of the missing link between icon and object. Eye-cons are more honest—they are tricks of vision so that what is seen does not necessarily correspond to what is presented. They are visual allusions rather than visual illusions, although they can display illusory effects. At its broadest, icon can be equated with image. The concept of image has thrived on its vagueness, and so attempts have been made to refine it. An icon corresponds to an optical image: it shares some of the projective characteristics of the object represented. Written words are also icons but they do not resemble the objects they represent—they are stylised or conventional rather than spatialised and projective. Words and images were set in delightful opposition by René Magritte (1898-1967 in a series of pipe paintings, and he also played on the theme of the arbitrariness of the verbal labels assigned to objects. What is surprising is that Magritte did not apply his painterly skills to transforming the word shapes he used. A similar reluctance to transform the typefaces pervades visual poetry. My interests are in the visual rather than the poetic dimension, and I will present a range of my own eye contricks which play with letter and word shapes in a variety of ways.

  13. Temporal properties of the lens eyes of the box jellyfish Tripedalia cystophora

    DEFF Research Database (Denmark)

    O'Connor, Megan; Nilsson, Dan-E; Garm, Anders Lydik

    2010-01-01

    Box jellyWsh (Cubomedusae) are visually orientating animals which posses a total of 24 eyes of 4 morphological types; 2 pigment cup eyes (pit eye and slit eye) and 2 lens eyes [upper lens-eye (ule) and lower lens-eye (lle)]. In this study, we use electroretinograms (ERGs) to explore temporal prop...

  14. Eye-movements and ongoing task processing.

    Science.gov (United States)

    Burke, David T; Meleger, Alec; Schneider, Jeffrey C; Snyder, Jim; Dorvlo, Atsu S S; Al-Adawi, Samir

    2003-06-01

    This study tests the relation between eye-movements and thought processing. Subjects were given specific modality tasks (visual, gustatory, kinesthetic) and assessed on whether they responded with distinct eye-movements. Some subjects' eye-movements reflected ongoing thought processing. Instead of a universal pattern, as suggested by the neurolinguistic programming hypothesis, this study yielded subject-specific idiosyncratic eye-movements across all modalities. Included is a discussion of the neurolinguistic programming hypothesis regarding eye-movements and its implications for the eye-movement desensitization and reprocessing theory.

  15. Circumventing 'free care' and 'shouting louder': using a health systems approach to study eye health system sustainability in government and mission facilities of north-west Tanzania.

    Science.gov (United States)

    Palmer, Jennifer J; Gilbert, Alice; Choy, Michelle; Blanchet, Karl

    2016-09-09

    Little is known about the contributions of faith-based organisations (FBOs) to health systems in Africa. In the specialist area of eye health, international and domestic Christian FBOs have been important contributors as service providers and donors, but they are also commonly critiqued as having developed eye health systems parallel to government structures which are unsustainable. In this study, we use a health systems approach (quarterly interviews, a participatory sustainability analysis exercise and a social network analysis) to describe the strategies used by eye care practitioners in four hospitals of north-west Tanzania to navigate the government, church mission and donor rules that govern eye services delivery there. Practitioners in this region felt eye care was systemically neglected by government and therefore was 'all under the NGOs', but support from international donors was also precarious. Practitioners therefore adopted four main strategies to improve the sustainability of their services: (1) maintain 'sustainability funds' to retain financial autonomy over income; (2) avoid granting government user fee exemptions to elderly patients who are the majority of service users; (3) expand or contract outreach services as financial circumstances change; and (4) access peer support for problem-solving and advocacy. Mission-based eye teams had greater freedom to increase their income from user fees by not implementing government policies for 'free care'. Teams in all hospitals, however, found similar strategies to manage their programmes even when their management structures were unique, suggesting the importance of informal rules shared through a peer network in governing eye care in this pluralistic health system. Health systems research can generate new evidence on the social dynamics that cross public and private sectors within a local health system. In this area of Tanzania, Christian FBOs' investments are important, not only in terms of the population

  16. Dorsal eye selector pannier (pnr) suppresses the eye fate to define dorsal margin of the Drosophila eye

    Science.gov (United States)

    Oros, Sarah M.; Tare, Meghana; Kango-Singh, Madhuri; Singh, Amit

    2010-01-01

    Axial patterning is crucial for organogenesis. During Drosophila eye development, dorso-ventral (DV) axis determination is the first lineage restriction event. The eye primordium begins with a default ventral fate, on which the dorsal eye fate is established by expression of the GATA-1 transcription factor pannier (pnr). Earlier, it was suggested that loss of pnr function induces enlargement in the dorsal eye due to ectopic equator formation. Interestingly, we found that in addition to regulating DV patterning, pnr suppresses the eye fate by downregulating the core retinal determination genes eyes absent (eya), sine oculis (so) and dacshund (dac) to define the dorsal eye margin. We found that pnr acts downstream of Ey and affect the retinal determination pathway by suppressing eya. Further analysis of the “eye suppression” function of pnr revealed that this function is likely mediated through suppression of the homeotic gene teashirt (tsh) and is independent of homothorax (hth), a negative regulator of eye. Pnr expression is restricted to the peripodial membrane on the dorsal eye margin, which gives rise to head structures around the eye, and pnr is not expressed in the eye disc proper that forms the retina. Thus, pnr has dual function, during early developmental stages pnr is involved in axial patterning whereas later it promotes the head specific fate. These studies will help in understanding the developmental regulation of boundary formation of the eye field on the dorsal eye margin. PMID:20691679

  17. The Association between Dry Eye Disease and Physical Activity as well as Sedentary Behavior: Results from the Osaka Study

    Directory of Open Access Journals (Sweden)

    Motoko Kawashima

    2014-01-01

    Full Text Available Purpose. To assess the association of dry eye disease (DED with physical activity and sedentary behavior. Methods. The cross-sectional survey conducted included Japanese office workers who use visual display terminals (n=672. DED was assessed according to the Japanese Dry Eye Diagnostic Criteria, and participants were categorized into “definite DED,” “probable DED,” or “non-DED” groups based on the results of DED examinations. Physical activity and sedentary behavior of participants were assessed using the International Physical Activity Questionnaire (IPAQ, and physical activity level was calculated in metabolic equivalent units per week (MET, min/week. Participants were classified as having a high, moderate, or low level of physical activity. Results. Participants with abnormal tear break-up time (BUT (≤5 s were involved in sedentary behavior for significantly longer duration than those with normal BUT (P=0.035. Non-DED participants (14.5% tended to have higher levels of physical activity than definite DED participants (2.5%. Participants with definite DED had significantly lower MET scores than those with non-DED (P=0.025. Conclusions. Our findings suggest that a lower level of physical activity and sedentary behavior are associated with DED; however, longitudinal/intervention studies with large groups of participants are needed to validate these findings.

  18. Attentional bias scores in patients with depression and effects of age: a controlled, eye-tracking study.

    Science.gov (United States)

    Lu, Shengfu; Xu, Jiying; Li, Mi; Xue, Jia; Lu, Xiaofeng; Feng, Lei; Fu, Bingbing; Wang, Gang; Zhong, Ning; Hu, Bin

    2017-10-01

    Objective To compare the attentional bias of depressed patients and non-depressed control subjects and examine the effects of age using eye-tracking technology in a free-viewing set of tasks. Methods Patients with major depressive disorder (MDD) and non-depressed control subjects completed an eye-tracking task to assess attention of processing negative, positive and neutral facial expressions. In this cross-sectional study, the tasks were separated in two types (neutral versus happy faces and neutral versus sad faces) and assessed in two age groups ('young' [18-30 years] and 'middle-aged' [31-55 years]). Results Compared with non-depressed control subjects ( n = 75), patients with MDD ( n = 90) had a significant reduced positive attentional bias and enhanced negative attentional bias irrespective of age. The positive attentional bias in 'middle-aged' patients with MDD was significantly lower than in 'young' patients, although there was no difference between the two age groups in negative attentional bias. Conclusions These results confirm that there are emotional attentional biases in patients with MDD and that positive attentional biases are influenced by age.

  19. Temporal and Spatial Aspects of Gas Release During the 2010 Apparition of Comet 103P/Hartley 2

    Science.gov (United States)

    Mumma, M. J.; Bonev, B. P.; Villanueva, G. L.; Paganini, L.; DiSanti, M. A.; Gibb, E. L.; Keane, J. V.; Meech, K. J.; Blake, G. A.; Ellis, R. S.; Lippi, M.; Boehnhardt, H.; Magee-Sauer, K.

    2011-06-01

    We report measurements of eight primary volatiles (H2O, HCN, CH4, C2H6, CH3OH, C2H2, H2CO, and NH3) and two product species (OH and NH2) in comet 103P/Hartley 2 using high-dispersion infrared spectroscopy. We quantified the long- and short-term behavior of volatile release over a three-month interval that encompassed the comet's close approach to Earth, its perihelion passage, and flyby of the comet by the Deep Impact spacecraft during the EPOXI mission. We present production rates for individual species, their mixing ratios relative to water, and their spatial distributions in the coma on multiple dates. The production rates for water, ethane, HCN, and methanol vary in a manner consistent with independent measures of nucleus rotation, but mixing ratios for HCN, C2H6, and CH3OH are independent of rotational phase. Our results demonstrate that the ensemble average composition of gas released from the nucleus is well defined and relatively constant over the three-month interval (September 18 through December 17). If individual vents vary in composition, enough diverse vents must be active simultaneously to approximate (in sum) the bulk composition of the nucleus. The released primary volatiles exhibit diverse spatial properties which favor the presence of separate polar and apolar ice phases in the nucleus, establish dust and gas release from icy clumps (and from the nucleus), and provide insights into the driver for the cyanogen (CN) polar jet. The spatial distributions of C2H6 and HCN along the near-polar jet (UT October 19.5) and nearly orthogonal to it (UT October 22.5) are discussed relative to the origin of CN. The ortho-para ratio (OPR) of water was 2.85 ± 0.20; the lower bound (2.65) defines T spin > 32 K. These values are consistent with results returned from the Infrared Space Observatory in 1997. Based on data collected at the W. M. Keck Observatory, Mauna Kea, Hawaii, and at ESO's Very Large Telescope, Paranal, Chile, under program 085.C-0229(A).

  20. Temporal and Spatial Aspects of Gas Release During the 2010 Apparition of Comet 103P/Hartley-2

    Science.gov (United States)

    Mumma, M. J.; Bonev, B. P.; Villanueva, G. L.; Paganini, L.; DiSanti, M. A.; Gibb, E. L.; Keane, J. V.; Meech, K. J.; Blake, G. A.; Ellis, R. S.; Lippi, M.; Boehnhardt, H.; Magee-Sauer, K.

    2011-01-01

    We report measurements of eight primary volatiles (H2O, HCN, CH4, C2H6, CH3OH, C2H2, H2CO, and NH3) and two product species (OH and NH2) in comet lO3P/Hartley-2 using high dispersion infrared spectroscopy. We quantified the long- and short-term behavior of volatile release over a three-month interval that encompassed the comet's close approach to Earth, its perihelion passage, and flyby of the comet by the Deep Impact spacecraft during the EPOXI mission. We present production rates for individual species, their mixing ratios relative to water, and their spatial distributions in the coma on multiple dates. The production rates for water, ethane, HCN, and methanol vary in a manner consistent with independent measures of nucleus rotation, but mixing ratios for HCN, C2H6, & CH3OH are independent of rotational phase. Our results demonstrate that the ensemble average composition of gas released from the nucleus is well defined, and relatively constant over the three-month interval (September 18 through December 1,7). If individual vents vary in composition, enough diverse vents must be active simultaneously to approximate (in sum) the bulk composition of the nucleus. The released primary volatiles exhibit diverse spatial properties which favor the presence of separate polar and apolar ice phases in the nucleus, establish dust and gas release from icy clumps, and from the nucleus, and provide insights into the driver for the cyanogen (CN) polar jet. The spatial distributions of C2H6 & HCN along the near-polar jet (UT 19.5 October) and nearly orthogonal to it (UT 22.5 October) are discussed relative to the origin of CN. The ortho-para ratio (OPR) of water was 2.85 +/- 0.20; the lower bound (2.65) defines T(sub spin) > 32 K. These values are consistent with results returned from ISO in 1997 .