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Sample records for rapid eye mount

  1. Rapid eye movement sleep behavior disorder

    DEFF Research Database (Denmark)

    Schenck, C H; Montplaisir, J Y; Frauscher, B

    2013-01-01

    We aimed to provide a consensus statement by the International Rapid Eye Movement Sleep Behavior Disorder Study Group (IRBD-SG) on devising controlled active treatment studies in rapid eye movement sleep behavior disorder (RBD) and devising studies of neuroprotection against Parkinson disease (PD...

  2. Degeneration of rapid eye movement sleep circuitry underlies rapid eye movement sleep behavior disorder.

    Science.gov (United States)

    McKenna, Dillon; Peever, John

    2017-05-01

    During healthy rapid eye movement sleep, skeletal muscles are actively forced into a state of motor paralysis. However, in rapid eye movement sleep behavior disorder-a relatively common neurological disorder-this natural process is lost. A lack of motor paralysis (atonia) in rapid eye movement sleep behavior disorder allows individuals to actively move, which at times can be excessive and violent. At first glance this may sound harmless, but it is not because rapid eye movement sleep behavior disorder patients frequently injure themselves or the person they sleep with. It is hypothesized that the degeneration or dysfunction of the brain stem circuits that control rapid eye movement sleep paralysis is an underlying cause of rapid eye movement sleep behavior disorder. The link between brain stem degeneration and rapid eye movement sleep behavior disorder stems from the fact that rapid eye movement sleep behavior disorder precedes, in the majority (∼80%) of cases, the development of synucleinopathies such as Parkinson's disease, dementia with Lewy bodies, and multiple system atrophy, which are known to initially cause degeneration in the caudal brain stem structures where rapid eye movement sleep circuits are located. Furthermore, basic science and clinical evidence demonstrate that lesions within the rapid eye movement sleep circuits can induce rapid eye movement sleep-specific motor deficits that are virtually identical to those observed in rapid eye movement sleep behavior disorder. This review examines the evidence that rapid eye movement sleep behavior disorder is caused by synucleinopathic neurodegeneration of the core brain stem circuits that control healthy rapid eye movement sleep and concludes that rapid eye movement sleep behavior disorder is not a separate clinical entity from synucleinopathies but, rather, it is the earliest symptom of these disorders. © 2017 International Parkinson and Movement Disorder Society. © 2017 International Parkinson and

  3. Rapid mounting of adult Drosophila structures in Hoyer's medium.

    Science.gov (United States)

    Stern, David L; Sucena, Elio

    2012-01-01

    The Drosophila cuticle carries a rich array of morphological details. Thus, cuticle examination has had a central role in the history of genetics. This protocol describes a procedure for mounting adult cuticles in Hoyer's medium, a useful mountant for both larval and adult cuticles. The medium digests soft tissues rapidly, leaving the cuticle cleared for observation. In addition, samples can be transferred directly from water to Hoyer's medium. However, specimens mounted in Hoyer's medium degrade over time. For example, the fine denticles on the larval dorsum are best observed soon after mounting; they begin to fade after 1 week, and can disappear completely after several months. More robust features, such as the ventral denticle belts, will persist for a longer period of time. Because adults cannot profitably be mounted whole in Hoyer's medium, some dissection is necessary.

  4. Using Priors to Compensate Geometrical Problems in Head-Mounted Eye Trackers

    DEFF Research Database (Denmark)

    Batista Narcizo, Fabricio; Ahmed, Zaheer; Hansen, Dan Witzner

    The use of additional information (a.k.a. priors) to help the eye tracking process is presented as an alternative to compensate classical geometrical problems in head-mounted eye trackers. Priors can be obtained from several distinct sources, such as: sensors to collect information related...... estimation specially for uncalibrated head-mounted setups....

  5. Fluid Mixing in the Eye Under Rapid Eye Movement

    Science.gov (United States)

    Huang, Jinglin; Gharib, Morteza

    2017-11-01

    Drug injection is an important technique in certain treatments of eye diseases. The efficacy of chemical mixing plays an important role in determining pharmacokinetics of injected drugs. In this study, we build a device to study the chemical mixing behavior in a spherical structure. The mixing process is visualized and analyzed qualitatively. We hope to understand the chemical convection and diffusion behaviors in correlation with controlled rapid mechanical movements. The results will have potential applications in treatment of eye diseases. Resnick Institute at Caltech.

  6. Rapid eye movement sleep behavior disorder

    DEFF Research Database (Denmark)

    Zoetmulder, Marielle; Jennum, Poul

    2009-01-01

    Rapid eye movement (REM) sleep behaviour disorder (RBD) is characterized by loss of REM sleep and related electromyographic atonia with marked muscular activity and dream enactment behaviour. RBD is seen in 0.5% of the population. It occurs in an idiopathic form and secondarily to medical...

  7. A new mapping function in table-mounted eye tracker

    Science.gov (United States)

    Tong, Qinqin; Hua, Xiao; Qiu, Jian; Luo, Kaiqing; Peng, Li; Han, Peng

    2018-01-01

    Eye tracker is a new apparatus of human-computer interaction, which has caught much attention in recent years. Eye tracking technology is to obtain the current subject's "visual attention (gaze)" direction by using mechanical, electronic, optical, image processing and other means of detection. While the mapping function is one of the key technology of the image processing, and is also the determination of the accuracy of the whole eye tracker system. In this paper, we present a new mapping model based on the relationship among the eyes, the camera and the screen that the eye gazed. Firstly, according to the geometrical relationship among the eyes, the camera and the screen, the framework of mapping function between the pupil center and the screen coordinate is constructed. Secondly, in order to simplify the vectors inversion of the mapping function, the coordinate of the eyes, the camera and screen was modeled by the coaxial model systems. In order to verify the mapping function, corresponding experiment was implemented. It is also compared with the traditional quadratic polynomial function. And the results show that our approach can improve the accuracy of the determination of the gazing point. Comparing with other methods, this mapping function is simple and valid.

  8. Parallax error in the monocular head-mounted eye trackers

    DEFF Research Database (Denmark)

    Mardanbeigi, Diako; Witzner Hansen, Dan

    2012-01-01

    each parameter affects the error. The optimum distribution of the error (magnitude and direction) in the field of view varies for different applications. However, the results can be used for finding the optimum parameters that are needed for designing a head-mounted gaze tracker. It has been shown...

  9. Application of head-mounted devices with eye-tracking in virtual reality therapy

    Directory of Open Access Journals (Sweden)

    Lutz Otto Hans-Martin

    2017-03-01

    Full Text Available Using eye-tracking to assess visual attention in head-mounted devices (HMD opens up many possibilities for virtual reality (VR-based therapy. Existing therapy concepts where attention plays a major role can be transferred to VR. Furthermore, they can be expanded to a precise real-time attention assessment, which can serve as a foundation for new therapy approaches. Utilizing HMDs and eye-tracking in a clinical environment is challenging because of hygiene issues and requirements of patients with heterogeneous cognitive and motor impairments. In this paper, we provide an overview of those challenges, discuss possible solutions and present preliminary results of a study with patients.

  10. Rapid eye movement sleep behavior disorder and rapid eye movement sleep without atonia in narcolepsy

    DEFF Research Database (Denmark)

    Dauvilliers, Yves; Jennum, Poul; Plazzi, Giuseppe

    2013-01-01

    Narcolepsy is a rare disabling hypersomnia disorder that may include cataplexy, sleep paralysis, hypnagogic hallucinations, and sleep-onset rapid eye movement (REM) periods, but also disrupted nighttime sleep by nocturnal awakenings, and REM sleep behavior disorder (RBD). RBD is characterized...... by dream-enacting behavior and impaired motor inhibition during REM sleep (REM sleep without atonia, RSWA). RBD is commonly associated with neurodegenerative disorders including Parkinsonisms, but is also reported in narcolepsy in up to 60% of patients. RBD in patients with narcolepsy is, however...... with narcolepsy often present dissociated sleep features including RSWA, increased density of phasic chin EMG and frequent shift from REM to NREM sleep, with or without associated clinical RBD. Most patients with narcolepsy with cataplexy lack the hypocretin neurons in the lateral hypothalamus. Tonic and phasic...

  11. KOH mount as an aid in the management of infectious keratitis at secondary eye care centre.

    Science.gov (United States)

    Rathi, Varsha M; Thakur, Monica; Sharma, Savitri; Khanna, Rohit; Garg, Prashant

    2017-11-01

    To report the clinical outcome of infectious keratitis managed after doing 10% KOH mount of corneal smears and reporting done by an ophthalmologist in the secondary eye care centre in South India. 103 consecutive cases of microbial keratitis were studied. Inclusion criteria were presence of corneal infiltrate on slit lamp biomicroscopy. An ophthalmologist carried out microbiological evaluation of 10% KOH mount of corneal scrapings. No cultures were done at secondary centres. Antifungal therapy with 5% Natamycin was initiated when 10% KOH mount was positive for fungal filaments. Else, the patients were started on combined topical ciprofloxacin (0.3%) and fortified cefazolin (5%). 41/103 (39.8%) smears were positive for fungus and 62 (60.2%) were negative. 89 out of 103 patients (86.40%) healed with scarring at an average of 2.95±1.58 weeks. Healing was noted in 39/41 (95.12%) of patients at an average of 3.06±1.19 weeks in patients with KOH smear positive keratitis. 80.64% (50/62) healed with scarring at an average period of 2.86±1.86 weeks in KOH mount negative keratitis. Initial smear examination of KOH mount by an ophthalmologist helped in diagnosis of infectious keratitis caused by fungi and its management and 95.12% of KOH positive patients healed with scarring. Reading of KOH mount by an ophthalmologist helped in initiation of specific therapy with improved clinical outcome. © 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.

  12. A Statistical Approach to Continuous Self-Calibrating Eye Gaze Tracking for Head-Mounted Virtual Reality Systems

    OpenAIRE

    Tripathi, Subarna; Guenter, Brian

    2016-01-01

    We present a novel, automatic eye gaze tracking scheme inspired by smooth pursuit eye motion while playing mobile games or watching virtual reality contents. Our algorithm continuously calibrates an eye tracking system for a head mounted display. This eliminates the need for an explicit calibration step and automatically compensates for small movements of the headset with respect to the head. The algorithm finds correspondences between corneal motion and screen space motion, and uses these to...

  13. Head-mounted eye tracking of a chimpanzee under naturalistic conditions.

    Directory of Open Access Journals (Sweden)

    Fumihiro Kano

    Full Text Available This study offers a new method for examining the bodily, manual, and eye movements of a chimpanzee at the micro-level. A female chimpanzee wore a lightweight head-mounted eye tracker (60 Hz on her head while engaging in daily interactions with the human experimenter. The eye tracker recorded her eye movements accurately while the chimpanzee freely moved her head, hands, and body. Three video cameras recorded the bodily and manual movements of the chimpanzee from multiple angles. We examined how the chimpanzee viewed the experimenter in this interactive setting and how the eye movements were related to the ongoing interactive contexts and actions. We prepared two experimentally defined contexts in each session: a face-to-face greeting phase upon the appearance of the experimenter in the experimental room, and a subsequent face-to-face task phase that included manual gestures and fruit rewards. Overall, the general viewing pattern of the chimpanzee, measured in terms of duration of individual fixations, length of individual saccades, and total viewing duration of the experimenter's face/body, was very similar to that observed in previous eye-tracking studies that used non-interactive situations, despite the differences in the experimental settings. However, the chimpanzee viewed the experimenter and the scene objects differently depending on the ongoing context and actions. The chimpanzee viewed the experimenter's face and body during the greeting phase, but viewed the experimenter's face and hands as well as the fruit reward during the task phase. These differences can be explained by the differential bodily/manual actions produced by the chimpanzee and the experimenter during each experimental phase (i.e., greeting gestures, task cueing. Additionally, the chimpanzee's viewing pattern varied depending on the identity of the experimenter (i.e., the chimpanzee's prior experience with the experimenter. These methods and results offer new

  14. "Head up and eyes out" advances in head mounted displays capabilities

    Science.gov (United States)

    Cameron, Alex

    2013-06-01

    There are a host of helmet and head mounted displays, flooding the market place with displays which provide what is essentially a mobile computer display. What sets aviators HMDs apart is that they provide the user with accurate conformal information embedded in the pilots real world view (see through display) where the information presented is intuitive and easy to use because it overlays the real world (mix of sensor imagery, symbolic information and synthetic imagery) and enables them to stay head up, eyes out, - improving their effectiveness, reducing workload and improving safety. Such systems are an enabling technology in the provision of enhanced Situation Awareness (SA) and reducing user workload in high intensity situations. Safety Is Key; so the addition of these HMD functions cannot detract from the aircrew protection functions of conventional aircrew helmets which also include life support and audio communications. These capabilities are finding much wider application in new types of compact man mounted audio/visual products enabled by the emergence of new families of micro displays, novel optical concepts and ultra-compact low power processing solutions. This papers attempts to capture the key drivers and needs for future head mounted systems for aviation applications.

  15. A Novel Contrast Stain for the Rapid Diagnosis of Pityriasis Versicolor: A Comparison of Chicago Sky Blue 6B Stain, Potassium Hydroxide Mount and Culture.

    Science.gov (United States)

    Lodha, Nikita; Poojary, Shital Amin

    2015-01-01

    The mycological study of pityriasis versicolor is usually done by potassium hydroxide (KOH) mount and culture. However, KOH mount lacks a color contrast and requires a trained eye to interpret, while culture is difficult to perform, time consuming and has low sensitivity. Chicago Sky Blue 6B (CSB) is a new contrast stain that highlights the fungal hyphae and spores, blue against a purplish background. This study was done to compare the utility of a novel contrast stain (CSB stain) with KOH mount and culture. Skin scrapings from the lesions of 100 clinically diagnosed cases of P. versicolor were subjected to (1) KOH mount and CSB stain for direct microscopic examination and (2) culture using Sabouraud's dextrose agar. The statistical analysis of CSB stain and culture was done using KOH mount as the reference method, as it is the most commonly performed and practical diagnostic test available for P. versicolor. An interrater reliability analysis using the Cohen's Kappa statistic was performed to determine consistency (agreement) among the different modalities. Direct microscopy with CSB stain, KOH mount and mycological culture showed positive results in 98 (98%), 92 (92%) and 56 (56%) patients, respectively. Using KOH mount as the reference method, CSB stain had a sensitivity of 100% which was significantly higher than culture (60.9%). Statistically significant fair agreement was found between CSB stain and KOH mount (94% with κ=0.38, P < 0.001). Negligible agreement was found between CSB stain and culture (66%, κ=0.199, P = 0.001) as well as between KOH mount and culture (64%, κ=0.051, P = 0.107). CSB staining of skin scrapings is the most sensitive method for the diagnosis of pityriasis versicolor. Due to the distinct contrast provided by CSB, it is easy to perform, rapid and qualitatively superior to KOH mount.

  16. A novel contrast stain for the rapid diagnosis of pityriasis versicolor: A comparison of Chicago Sky Blue 6B stain, potassium hydroxide mount and culture

    Directory of Open Access Journals (Sweden)

    Nikita Lodha

    2015-01-01

    Full Text Available Background: The mycological study of pityriasis versicolor is usually done by potassium hydroxide (KOH mount and culture. However, KOH mount lacks a color contrast and requires a trained eye to interpret, while culture is difficult to perform, time consuming and has low sensitivity. Chicago Sky Blue 6B (CSB is a new contrast stain that highlights the fungal hyphae and spores, blue against a purplish background. Aims and Objectives: This study was done to compare the utility of a novel contrast stain (CSB stain with KOH mount and culture. Materials and Methods: Skin scrapings from the lesions of 100 clinically diagnosed cases of P. versicolor were subjected to (1 KOH mount and CSB stain for direct microscopic examination and (2 culture using Sabouraud′s dextrose agar. The statistical analysis of CSB stain and culture was done using KOH mount as the reference method, as it is the most commonly performed and practical diagnostic test available for P. versicolor. An interrater reliability analysis using the Cohen′s Kappa statistic was performed to determine consistency (agreement among the different modalities. Observations and Results: Direct microscopy with CSB stain, KOH mount and mycological culture showed positive results in 98 (98%, 92 (92% and 56 (56% patients, respectively. Using KOH mount as the reference method, CSB stain had a sensitivity of 100% which was significantly higher than culture (60.9%. Statistically significant fair agreement was found between CSB stain and KOH mount (94% with κ=0.38, P < 0.001. Negligible agreement was found between CSB stain and culture (66%, κ=0.199, P = 0.001 as well as between KOH mount and culture (64%, κ=0.051, P = 0.107. Conclusion: CSB staining of skin scrapings is the most sensitive method for the diagnosis of pityriasis versicolor. Due to the distinct contrast provided by CSB, it is easy to perform, rapid and qualitatively superior to KOH mount.

  17. Morbidities in rapid eye movement sleep behavior disorder

    DEFF Research Database (Denmark)

    Jennum, Poul; Mayer, Geert; Ju, Yo-El

    2013-01-01

    Idiopathic rapid eye movement (REM) sleep behavior disorder (iRBD, RBD without any obvious comorbid major neurological disease), is strongly associated with numerous comorbid conditions. The most prominent is that with neurodegenerative disorders, especially synuclein-mediated disorders, above all...... function, neuropsychiatric manifestations and sleep complaints. Furthermore, patients with PD and RBD may have worse prognosis in terms of impaired cognitive function and overall morbidity/mortality; in dementia, the presence of RBD is strongly associated with clinical hallmarks and pathological findings...

  18. Rapid assessment methods in eye care: An overview

    Directory of Open Access Journals (Sweden)

    Srinivas Marmamula

    2012-01-01

    Full Text Available Reliable information is required for the planning and management of eye care services. While classical research methods provide reliable estimates, they are prohibitively expensive and resource intensive. Rapid assessment (RA methods are indispensable tools in situations where data are needed quickly and where time- or cost-related factors prohibit the use of classical epidemiological surveys. These methods have been developed and field tested, and can be applied across almost the entire gamut of health care. The 1990s witnessed the emergence of RA methods in eye care for cataract, onchocerciasis, and trachoma and, more recently, the main causes of avoidable blindness and visual impairment. The important features of RA methods include the use of local resources, simplified sampling methodology, and a simple examination protocol/data collection method that can be performed by locally available personnel. The analysis is quick and easy to interpret. The entire process is inexpensive, so the survey may be repeated once every 5-10 years to assess the changing trends in disease burden. RA survey methods are typically linked with an intervention. This article provides an overview of the RA methods commonly used in eye care, and emphasizes the selection of appropriate methods based on the local need and context.

  19. Rapid eye movement sleep behaviour disorder in patients with narcolepsy is associated with hypocretin-1 deficiency

    DEFF Research Database (Denmark)

    Knudsen, Stine; Gammeltoft, Steen; Jennum, Poul J

    2010-01-01

    Rapid eye movement sleep behaviour disorder is characterized by dream-enacting behaviour and impaired motor inhibition during rapid eye movement sleep. Rapid eye movement sleep behaviour disorder is commonly associated with neurodegenerative disorders, but also reported in narcolepsy with cataplexy....... Most narcolepsy with cataplexy patients lack the sleep-wake, and rapid eye movement sleep, motor-regulating hypocretin neurons in the lateral hypothalamus. In contrast, rapid eye movement sleep behaviour disorder and hypocretin deficiency are rare in narcolepsy without cataplexy. We hypothesized...... that rapid eye movement sleep behaviour disorder coexists with cataplexy in narcolepsy due to hypocretin deficiency. In our study, rapid eye movement sleep behaviour disorder was diagnosed by the International Classification of Sleep Disorders (2nd edition) criteria in 63 narcolepsy patients with or without...

  20. [Parkinson Disease With Rapid Eye Movement Sleep Behavior Disorder].

    Science.gov (United States)

    Hu, Yang; Zhang, Wei

    2015-06-01

    Rapid eye movement (REM) sleep behavior disorder (RBD) is characterized by lack of muscle atonia during REM sleep and enactment of dream content. RBD is associated with Parkinson disease (PD) and has high incidence in PD patients. PD patient with RBD mainly presents rigid type, has longer disease duration, more severe motor and non-motor symptoms and poorer activity of daily living and life quality. The pathophysiological mechanisms of RBD may be related to dysfunctions of pontine tegmentum, locus coeruleus/sub-locus coeruleus complex and related projections. The diagnosis of RBD depends on clinical histories and video-polysomnography (v-PSG). Besides treatment for PD, protective measures have to be taken for patients and their sleep partners. If abnormal behaviors during sleep cause distress and danger,patients should be given drug therapy.

  1. Rapid eye movement sleep disturbances in Huntington disease

    DEFF Research Database (Denmark)

    Arnulf, I.; Nielsen, J.; Lohmann, E.

    2008-01-01

    and shortened rapid eye movement (REM) sleep, and increased periodic leg movements. Three HD patients (12%) had REM sleep behavior disorders. No sleep abnormality correlated with CAG repeat length. Reduced REM sleep duration (but not REM sleep behavior disorders) was present in premanifest carriers and patients...... with very mild HD and worsened with disease severity. In contrast to narcoleptic patients, HD patients had no cataplexy, hypnagogic hallucinations, or sleep paralysis. Four HD patients had abnormally low (sleep latencies, but none had multiple sleep-onset REM periods. Conclusions......: The sleep phenotype of HD includes insomnia, advanced sleep phase, periodic leg movements, REM sleep behavior disorders, and reduced REM sleep but not narcolepsy. Reduced REM sleep may precede chorea. Mutant huntingtin may exert an effect on REM sleep and motor control during sleep Udgivelsesdato: 2008/4...

  2. Characteristics of rapid eye movement sleep behavior disorder in narcolepsy

    DEFF Research Database (Denmark)

    Jennum, Poul Jørgen; Frandsen, Rune Asger Vestergaard; Knudsen, Stine

    2013-01-01

    Rapid eye movement (REM) sleep behavior disorder (RBD) is characterized by dream-enacting behavior and impaired motor inhibition during REM sleep (REM sleep without atonia, RSWA). RBD is commonly associated with Parkinsonian disorders, but is also reported in narcolepsy. Most patients...... of hypocretin deficiency. Thus, hypocretin deficiency is linked to the two major disturbances of REM sleep motor regulation in narcolepsy: RBD and cataplexy. Moreover, it is likely that hypocretin deficiency independently predicts periodic limb movements in REM and NREM sleep, probably via involvement...... of the dopaminergic system. This supports the hypothesis that an impaired hypocretin system causes general instability of motor regulation during wakefulness, REM and NREM sleep in human narcolepsy. We propose that hypocretin neurons are centrally involved in motor tone control during wakefulness and sleep in humans...

  3. Neurophysiological basis of rapid eye movement sleep behavior disorder

    DEFF Research Database (Denmark)

    Jennum, Poul; Christensen, Julie Anja Engelhard; Zoetmulder, Marielle

    2016-01-01

    Rapid eye movement (REM) sleep behavior disorder (RBD) is a parasomnia characterized by a history of recurrent nocturnal dream enactment behavior and loss of skeletal muscle atonia and increased phasic muscle activity during REM sleep: REM sleep without atonia. RBD and associated comorbidities have...... recently been identified as one of the most specific and potentially sensitive risk factors for later development of any of the alpha-synucleinopathies: Parkinson's disease, dementia with Lewy bodies, and other atypical parkinsonian syndromes. Several other sleep-related abnormalities have recently been...... identified in patients with RBD/Parkinson's disease who experience abnormalities in sleep electroencephalographic frequencies, sleep-wake transitions, wake and sleep stability, occurrence and morphology of sleep spindles, and electrooculography measures. These findings suggest a gradual involvement...

  4. Rapid eye movement sleep behaviour disorder in patients with narcolepsy is associated with hypocretin-1 deficiency

    DEFF Research Database (Denmark)

    Knudsen, Stine; Gammeltoft, Steen; Jennum, Poul J

    2010-01-01

    variables were analysed in relation to cataplexy and hypocretin deficiency with uni- and multivariate logistic/linear regression models, controlling for possible rapid eye movement sleep behaviour disorder biasing factors (age, gender, disease duration, previous anti-cataplexy medication). Only hypocretin......Rapid eye movement sleep behaviour disorder is characterized by dream-enacting behaviour and impaired motor inhibition during rapid eye movement sleep. Rapid eye movement sleep behaviour disorder is commonly associated with neurodegenerative disorders, but also reported in narcolepsy with cataplexy....... Most narcolepsy with cataplexy patients lack the sleep-wake, and rapid eye movement sleep, motor-regulating hypocretin neurons in the lateral hypothalamus. In contrast, rapid eye movement sleep behaviour disorder and hypocretin deficiency are rare in narcolepsy without cataplexy. We hypothesized...

  5. Rapid micromotor-based naked-eye immunoassay.

    Science.gov (United States)

    de Ávila, Berta Esteban-Fernández; Zhao, Mingjiao; Campuzano, Susana; Ricci, Francesco; Pingarrón, José M; Mascini, Marcello; Wang, Joseph

    2017-05-15

    A dynamic micromotor-based immunoassay, exemplified by cortisol detection, based on the use of tubular micromotors functionalized with a specific antibody is described. The use of antibody-functionalized micromotors offers huge acceleration of both direct and competitive cortisol immunoassays, along with greatly enhanced sensitivity of direct and competitive immunoassays. The dramatically improved speed and sensitivity reflect the greatly increased likelihood of antibody-cortisol contacts and fluid mixing associated with the dynamic movement of these microtube motors and corresponding bubble generation that lead to a highly efficient and rapid recognition process. Rapid naked-eye detection of cortisol in the sample is achieved in connection to use of horseradish peroxidase (HRP) tag and TMB/H 2 O 2 system. Key parameters of the competitive immunoassay (e.g., incubation time and reaction volume) were optimized. This fast visual micromotor-based sensing approach enables "on the move" specific detection of the target cortisol down to 0.1μgmL -1 in just 2min, using ultrasmall (50µL) sample volumes. Copyright © 2017 Elsevier B.V. All rights reserved.

  6. A rapid method for whole mount preparations of mammalian oocytes and early embryos.

    Science.gov (United States)

    Moses, R M; Masui, Y

    1994-05-01

    Whole mounts of mouse oocytes and embryos are useful for observing intracellular structures while preserving morphological integrity. This method is inconvenient for rapid processing of a large number of specimens because washing each specimen in a protein-free solution is required prior to transfer into the fixative. We have developed a new fixative which does not cause protein precipitation which can be added directly to the culture medium. Specimens can be preserved in culture dishes for at least one month, and processed for cytological observation at a convenient time. When stained with hematoxylin, details of cellular structures such as nuclei, nucleoli, chromosomes and spindle microtubules can be observed while maintaining the organization of the organelles.

  7. Ictal SPECT in patients with rapid eye movement sleep behaviour disorder.

    Science.gov (United States)

    Mayer, Geert; Bitterlich, Marion; Kuwert, Torsten; Ritt, Philipp; Stefan, Hermann

    2015-05-01

    Rapid eye movement sleep behaviour disorder is a rapid eye movement parasomnia clinically characterized by acting out dreams due to disinhibition of muscle tone in rapid eye movement sleep. Up to 80-90% of the patients with rapid eye movement sleep behaviour disorder develop neurodegenerative disorders within 10-15 years after symptom onset. The disorder is reported in 45-60% of all narcoleptic patients. Whether rapid eye movement sleep behaviour disorder is also a predictor for neurodegeneration in narcolepsy is not known. Although the pathophysiology causing the disinhibition of muscle tone in rapid eye movement sleep behaviour disorder has been studied extensively in animals, little is known about the mechanisms in humans. Most of the human data are from imaging or post-mortem studies. Recent studies show altered functional connectivity between substantia nigra and striatum in patients with rapid eye movement sleep behaviour disorder. We were interested to study which regions are activated in rapid eye movement sleep behaviour disorder during actual episodes by performing ictal single photon emission tomography. We studied one patient with idiopathic rapid eye movement sleep behaviour disorder, one with Parkinson's disease and rapid eye movement sleep behaviour disorder, and two patients with narcolepsy and rapid eye movement sleep behaviour disorder. All patients underwent extended video polysomnography. The tracer was injected after at least 10 s of consecutive rapid eye movement sleep and 10 s of disinhibited muscle tone accompanied by movements registered by an experienced sleep technician. Ictal single photon emission tomography displayed the same activation in the bilateral premotor areas, the interhemispheric cleft, the periaqueductal area, the dorsal and ventral pons and the anterior lobe of the cerebellum in all patients. Our study shows that in patients with Parkinson's disease and rapid eye movement sleep behaviour disorder-in contrast to wakefulness

  8. Naked-eye sensor for rapid determination of mercury ion.

    Science.gov (United States)

    Liu, Jing; Wu, Dapeng; Yan, Xiaohui; Guan, Yafeng

    2013-11-15

    A naked-eye paper sensor for rapid determination of trace mercury ion in water samples was designed and demonstrated. The mercury-sensing rhodamine B thiolactone was immobilized in silica matrices and the silica matrices were impregnated firmly and uniformly in the filter paper. As water samples flow through the filter paper, the membrane color will change from white to purple red, which could be observed obviously with naked eye, when concentration of mercury ions equals to or exceeds 10nM, the maximum residue level in drinking water recommended by U.S. EPA. The color change can also be recorded by a flatbed scanner and then digitized, reducing the detection limit of Hg(2+) down to 1.2 nM. Moreover, this method is extremely specific for Hg(2+) and shows a high tolerance ratio of interferent coexisting ions. The presence of Na(+) (2 mM), K(+) (2 mM), Fe(3+) (0.1 mM), Zn(2+) (0.1 mM), Mg(2+) (0.1 mM), Ni(2+) (50 μM), Co(2+) (50 μM), Cd(2+) (50 μM), Pb(2+) (50 μM), Cu(2+) (50 μM) and Ag(+) (3.5 μM) did not interfere with the detection of Hg(2+) (25 nM). Finally, the present method was applied in the detection of Hg(2+) in mineral water, tap water and pond water. Copyright © 2013 Elsevier B.V. All rights reserved.

  9. Investigating rapid eye movement sleep without atonia in Parkinson's disease using the rapid eye movement sleep behavior disorder screening questionnaire.

    Science.gov (United States)

    Bolitho, Samuel J; Naismith, Sharon L; Terpening, Zoe; Grunstein, Ron R; Melehan, Kerri; Yee, Brendon J; Coeytaux, Alessandra; Gilat, Moran; Lewis, Simon J G

    2014-05-01

    Rapid eye movement (REM) sleep behavior disorder (RBD) is frequently observed in patients with Parkinson's disease (PD). Accurate diagnosis is essential for managing this condition. Furthermore, the emergence of idiopathic RBD in later life can represent a premotor feature, heralding the development of PD. Reliable, accurate methods for identifying RBD may offer a window for early intervention. This study sought to identify whether the RBD screening questionnaire (RBDSQ) and three questionnaires focused on dream enactment were able to correctly identify patients with REM without atonia (RWA), the neurophysiological hallmark of RBD. Forty-six patients with PD underwent neurological and sleep assessment in addition to completing the RBDSQ, the RBD single question (RBD1Q), and the Mayo Sleep Questionnaire (MSQ). The REM atonia index was derived for all participants as an objective measure of RWA. Patients identified to be RBD positive on the RBDSQ did not show increased RWA on polysomnography (80% sensitivity and 55% specificity). However, patients positive for RBD on questionnaires specific to dream enactment correctly identified higher degrees of RWA and improved the diagnostic accuracy of these questionnaires. This study suggests that the RBDSQ does not accurately identify RWA, essential for diagnosing RBD in PD. Furthermore, the results suggest that self-report measures of RBD need to focus questions on dream enactment behavior to better identify RWA and RBD. Further studies are needed to develop accurate determination and quantification of RWA in RBD to improve management of patients with PD in the future. © 2014 International Parkinson and Movement Disorder Society.

  10. Dopamine transporter imaging in rapid eye movement sleep behavior disorder

    Energy Technology Data Exchange (ETDEWEB)

    Kim, Yu Kyeong; Yoon, In Young; Kim, Jong Min; Jeong, Seok Hoon; Kim, Ji Sun; Lee, Byung Chul; Lee, Won Woo; Kim, Sang Eun [Seoul National Univ. College of Medicine, Seoul (Korea, Republic of)

    2007-07-01

    The pathogenesis of rapid eye movement (REM) sleep behavior disorder (RBD) is still unknown. However, involvement of dopaminergic system in RBD has been hypothesized because of frequent association with degenerative movement disorders such as Parkinson's disease. The purpose of this study was to examine the extent and pattern of loss of dopamine transporter in RBD using FP-CIT SPECT. Fourteen patient with idiopathic RBD (mean age:665 yrs, M:F=10:3) participated in this study. Polysonmography confirmed loss of REM atonia and determined RBD severities by amount of tonic/phasic muscle activity during REM sleep in all cases. To compare with RBD, 14 early idiopathic Parkinson's disease rated as Hoehn and Yahr stage 1 (IPD) and 12 healthy controls were also selected. All participants performed single-photon emission computed tomography (SPECT) imaging 3 hours after injection of [123I]FP-CIT. Regions of interest were drawn on bilateral caudate and putamen, whole striatum and occipital cortex. Specific binding for dopamine transporters (DAT) were calculated using region to occipital uptake ratio based on the transient equilibrium method. Overall mean of DAT density in the striatum was lower in RBD group than controls, and higher than IPD group, However, DAT density in most individual RBD was still within normal range, and total striatal DAT density was not correlated with severity of RBD. Meanwhile, the caudate to putamen uptake ratio (C/P ratio) in RBD group was insignificantly higher than those in healthy controls. Nevertheless, C/P ratio within RBD group was reversely correlated with the RBD severity. Our study suggested that nigrostriatal dopaminergic degeneration could be a part of the pathogenesis of RBD, but not essential for the development of RBD. Further longitudinal evaluation of presynaptic dopaminergic system in idiopathic RBD may guarantee the more understanding for RBD and associated neurodegenerative disease.

  11. Activation of inactivation process initiates rapid eye movement sleep.

    Science.gov (United States)

    Mallick, Birendra Nath; Singh, Abhishek; Khanday, Mudasir Ahmad

    2012-06-01

    Interactions among REM-ON and REM-OFF neurons form the basic scaffold for rapid eye movement sleep (REMS) regulation; however, precise mechanism of their activation and cessation, respectively, was unclear. Locus coeruleus (LC) noradrenalin (NA)-ergic neurons are REM-OFF type and receive GABA-ergic inputs among others. GABA acts postsynaptically on the NA-ergic REM-OFF neurons in the LC and presynaptically on the latter's projection terminals and modulates NA-release on the REM-ON neurons. Normally during wakefulness and non-REMS continuous release of NA from the REM-OFF neurons, which however, is reduced during the latter phase, inhibits the REM-ON neurons and prevents REMS. At this stage GABA from substantia nigra pars reticulate acting presynaptically on NA-ergic terminals on REM-ON neurons withdraws NA-release causing the REM-ON neurons to escape inhibition and being active, may be even momentarily. A working-model showing neurochemical-map explaining activation of inactivation process, showing contribution of GABA-ergic presynaptic inhibition in withdrawing NA-release and dis-inhibition induced activation of REM-ON neurons, which in turn activates other GABA-ergic neurons and shutting-off REM-OFF neurons for the initiation of REMS-generation has been explained. Our model satisfactorily explains yet unexplained puzzles (i) why normally REMS does not appear during waking, rather, appears following non-REMS; (ii) why cessation of LC-NA-ergic-REM-OFF neurons is essential for REMS-generation; (iii) factor(s) which does not allow cessation of REM-OFF neurons causes REMS-loss; (iv) the association of changes in levels of GABA and NA in the brain during REMS and its deprivation and associated symptoms; v) why often dreams are associated with REMS. Copyright © 2012 Elsevier Ltd. All rights reserved.

  12. Flurbiprofen in rapid eye movement sleep deprivation induced hyperalgesia.

    Science.gov (United States)

    Gürel, Elif Ezgi; Ural, Keremcan; Öztürk, Gülnur; Öztürk, Levent

    2014-04-10

    Rapid eye movement (REM) sleep deprivation induces hyperalgesia in healthy rats. Here, we evaluated the effects of flurbiprofen, an anti-inflammatory and neuroprotective agent, on the increased thermal responses observed in REM sleep deprived rats. Forty female rats were divided into four groups following 96-hour REM sleep deprivation: intraperitoneal injections of placebo, and flurbiprofen 5 mg/kg, 15 mg/kg and 40 mg/kg were made in CONT (n=10), FBP5, FBP15 and FBP40 groups respectively. Pain threshold measurements were performed three times at baseline (0.hour), at the end of REM sleep deprivation (96.hour) and at 1 h after injections (97.hour) by hot plate and tail-flick tests. REM sleep deprivation induced a significant decrease in pain thresholds of all rats (hotplate: 0.hour vs 96.hour, 9.75±2.85 vs 5.10±2.02, pFlurbiprofen in 15 mg/kg and 40 mg/kg doses significantly improved pain tolerance measured by tail flick test (tail flick in FBP15 and FBP40 groups: 96.hour vs 97.hour, 7.01±4.97 vs 8.34±3.61 and 5.06±1.57 vs 7.04±2.49, pFlurbiprofen was used for the first time in a rat model of REM sleep deprivation, and it provided anti-nociceptive effects in 15 mg/kg and 40 mg/kg doses. Flurbiprofen may have the potential for treatment of painful syndromes accompanying insomnia or sleep loss. Copyright © 2014 Elsevier Inc. All rights reserved.

  13. Dopamine transporter imaging in rapid eye movement sleep behavior disorder

    International Nuclear Information System (INIS)

    Kim, Yu Kyeong; Yoon, In Young; Kim, Jong Min; Jeong, Seok Hoon; Kim, Ji Sun; Lee, Byung Chul; Lee, Won Woo; Kim, Sang Eun

    2007-01-01

    The pathogenesis of rapid eye movement (REM) sleep behavior disorder (RBD) is still unknown. However, involvement of dopaminergic system in RBD has been hypothesized because of frequent association with degenerative movement disorders such as Parkinson's disease. The purpose of this study was to examine the extent and pattern of loss of dopamine transporter in RBD using FP-CIT SPECT. Fourteen patient with idiopathic RBD (mean age:665 yrs, M:F=10:3) participated in this study. Polysonmography confirmed loss of REM atonia and determined RBD severities by amount of tonic/phasic muscle activity during REM sleep in all cases. To compare with RBD, 14 early idiopathic Parkinson's disease rated as Hoehn and Yahr stage 1 (IPD) and 12 healthy controls were also selected. All participants performed single-photon emission computed tomography (SPECT) imaging 3 hours after injection of [123I]FP-CIT. Regions of interest were drawn on bilateral caudate and putamen, whole striatum and occipital cortex. Specific binding for dopamine transporters (DAT) were calculated using region to occipital uptake ratio based on the transient equilibrium method. Overall mean of DAT density in the striatum was lower in RBD group than controls, and higher than IPD group, However, DAT density in most individual RBD was still within normal range, and total striatal DAT density was not correlated with severity of RBD. Meanwhile, the caudate to putamen uptake ratio (C/P ratio) in RBD group was insignificantly higher than those in healthy controls. Nevertheless, C/P ratio within RBD group was reversely correlated with the RBD severity. Our study suggested that nigrostriatal dopaminergic degeneration could be a part of the pathogenesis of RBD, but not essential for the development of RBD. Further longitudinal evaluation of presynaptic dopaminergic system in idiopathic RBD may guarantee the more understanding for RBD and associated neurodegenerative disease

  14. [Electromyography Analysis of Rapid Eye Movement Sleep Behavior Disorder].

    Science.gov (United States)

    Nakano, Natsuko; Kinoshita, Fumiya; Takada, Hiroki; Nakayama, Meiho

    2018-01-01

    Polysomnography (PSG), which records physiological phenomena including brain waves, breathing status, and muscle tonus, is useful for the diagnosis of sleep disorders as a gold standard. However, measurement and analysis are complex for several specific sleep disorders, such as rapid eye movement (REM) sleep behavior disorder (RBD). Usually, brain waves during REM sleep indicate an awakening pattern under relaxed conditions of skeletal and antigravity muscles. However, these muscles are activated during REM sleep when patients suffer from RBD. These activated muscle movements during REM, so-called REM without atonia (RWA) recorded by PSG, may be related to a neurodegenerative disease such as Parkinson's disease. Thus, careful analysis of RWA is significant not only physically, but also clinically. Commonly, manual viewing measurement analysis of RWA is time-consuming. Therefore, quantitative studies on RWA are rarely reported. A software program, developed from Microsoft Office Excel ® , was used to semiautomatically analyze the RWA ratio extracted from PSG to compare with manual viewing measurement analysis. In addition, a quantitative muscle tonus study was carried out to evaluate the effect of medication on RBD patients. Using this new software program, we were able to analyze RWA on the same cases in approximately 15 min as compared with 60 min in the manual viewing measurement analysis. This software program can not only quantify RWA easily but also identify RWA waves for either phasic or tonic bursts. We consider that this software program will support physicians and scientists in their future research on RBD. We are planning to offer this software program for free to physicians and scientists.

  15. Mapping soil heterogeneity using RapidEye satellite images

    Science.gov (United States)

    Piccard, Isabelle; Eerens, Herman; Dong, Qinghan; Gobin, Anne; Goffart, Jean-Pierre; Curnel, Yannick; Planchon, Viviane

    2016-04-01

    In the frame of BELCAM, a project funded by the Belgian Science Policy Office (BELSPO), researchers from UCL, ULg, CRA-W and VITO aim to set up a collaborative system to develop and deliver relevant information for agricultural monitoring in Belgium. The main objective is to develop remote sensing methods and processing chains able to ingest crowd sourcing data, provided by farmers or associated partners, and to deliver in return relevant and up-to-date information for crop monitoring at the field and district level based on Sentinel-1 and -2 satellite imagery. One of the developments within BELCAM concerns an automatic procedure to detect soil heterogeneity within a parcel using optical high resolution images. Such heterogeneity maps can be used to adjust farming practices according to the detected heterogeneity. This heterogeneity may for instance be caused by differences in mineral composition of the soil, organic matter content, soil moisture or soil texture. Local differences in plant growth may be indicative for differences in soil characteristics. As such remote sensing derived vegetation indices may be used to reveal soil heterogeneity. VITO started to delineate homogeneous zones within parcels by analyzing a series of RapidEye images acquired in 2015 (as a precursor for Sentinel-2). Both unsupervised classification (ISODATA, K-means) and segmentation techniques were tested. Heterogeneity maps were generated from images acquired at different moments during the season (13 May, 30 June, 17 July, 31 August, 11 September and 1 November 2015). Tests were performed using blue, green, red, red edge and NIR reflectances separately and using derived indices such as NDVI, fAPAR, CIrededge, NDRE2. The results for selected winter wheat, maize and potato fields were evaluated together with experts from the collaborating agricultural research centers. For a few fields UAV images and/or yield measurements were available for comparison.

  16. The Correlation between Clinical Variables and Sleep Onset Rapid Eye Movement Period Frequencies in Narcoleptic Patients

    Directory of Open Access Journals (Sweden)

    Jin Hwa Jeong

    2010-11-01

    Full Text Available Background and Objective A diagnosis of narcolepsy is defined by less than 8 minutes of mean sleep latency, and two or more sleep onset rapid eye movement periods on the Multiple Sleep Latency Test. This study examined the relationship between the sleep onset rapid eye movement period frequencies during Multiple Sleep Latency Test and narcoleptic symptom severity. Methods From March 2004 to August 2009, 126 patients suffering from excessive daytime sleepiness who visited the Sleep Disorders Clinic of St. Vincent’s Hospital at the Catholic University of Korea were tested by polysomnography and Multiple Sleep Latency Test. Subjects were divided into three groups according to the number of sleep onset rapid eye movement periods that appeared on the Multiple Sleep Latency Test. Symptom severity instruments included the Epworth Sleepiness Scale and the Stanford Center for Narcolepsy Sleep Inventory, and various sleep parameters. In addition, we performed human leukocyte antigen genotyping for human leukocyte antigen-DQB1*0602 on all patients. Results Among the three groups classified by the number of sleep onset rapid eye movement periods during Multiple Sleep Latency Test, we found no significant differences in demographic features, Epworth Sleepiness Scale, and most polysomnographic findings. However, we observed cataplexy, hypnagogic hallucination, sleep paralysis, and human leukocyte antigen-DQB1*0602 positivity more frequently in groups with higher sleep onset rapid eye movement period frequencies. In addition, the proportions of stage II sleep, REM sleep latency from polysomnography, and mean sleep latency and mean REM sleep latency from the Multiple Sleep Latency Test significantly decreased with increasing sleep onset rapid eye movement period frequency. Conclusions In this study, we demonstrated that sleep onset rapid eye movement period frequency during Multiple Sleep Latency Test correlated with sleep architecture, daytime symptom

  17. Quality of life in patients with an idiopathic rapid eye movement sleep behaviour disorder in Korea.

    Science.gov (United States)

    Kim, Keun Tae; Motamedi, Gholam K; Cho, Yong Won

    2017-08-01

    There have been few quality of life studies in patients with idiopathic rapid eye movement sleep behaviour disorder. We compared the quality of life in idiopathic rapid eye movement sleep behaviour disorder patients to healthy controls, patients with hypertension, type 2 diabetes mellitus without complication and idiopathic restless legs syndrome. Sixty patients with idiopathic rapid eye movement sleep behaviour disorder (24 female; mean age: 61.43 ± 8.99) were enrolled retrospectively. The diagnosis was established based on sleep history, overnight polysomnography, neurological examination and Mini-Mental State Examination to exclude secondary rapid eye movement sleep behavior disorder. All subjects completed questionnaires, including the Short Form 36-item Health Survey for quality of life. The total quality of life score in idiopathic rapid eye movement sleep behaviour disorder (70.63 ± 20.83) was lower than in the healthy control group (83.38 ± 7.96) but higher than in the hypertension (60.55 ± 24.82), diabetes mellitus (62.42 ± 19.37) and restless legs syndrome (61.77 ± 19.25) groups. The total score of idiopathic rapid eye movement sleep behaviour disorder patients had a negative correlation with the Pittsburg Sleep Quality Index (r = -0.498, P sleep behaviour disorder had a significant negative impact on quality of life, although this effect was less than that of other chronic disorders. This negative effect might be related to a depressive mood associated with the disease. © 2016 European Sleep Research Society.

  18. Role of norepinephrine in the regulation of rapid eye movement sleep

    Indian Academy of Sciences (India)

    Sleep and wakefulness are instinctive behaviours that are present across the animal species. Rapid eye movement (REM) sleep is a unique biological phenomenon expressed during sleep. It evolved about 300 million years ago and is noticed in the more evolved animal species. Although it has been objectively identified ...

  19. Extrastriatal monoaminergic dysfunction and enhanced microglial activation in idiopathic rapid eye movement sleep behaviour disorder

    DEFF Research Database (Denmark)

    Stokholm, Morten Gersel; Iranzo, Alex; Østergaard, Karen

    2018-01-01

    BACKGROUND: The majority of patients diagnosed with idiopathic rapid eye movement sleep behaviour disorder (iRBD) progress over time to a Lewy-type α-synucleinopathy such as Parkinson's disease or dementia with Lewy bodies. This in vivo molecular imaging study aimed to investigate if extrastriatal...

  20. Rapid eye movement sleep behavior disorder--diagnostik, årsager og behandling

    DEFF Research Database (Denmark)

    Zoetmulder, Marielle; Jennum, Poul Jørgen

    2009-01-01

    Rapid eye movement (REM) sleep behaviour disorder (RBD) is characterized by loss of REM sleep and related electromyographic atonia with marked muscular activity and dream enactment behaviour. RBD is seen in 0.5% of the population. It occurs in an idiopathic form and secondarily to medical and neu...

  1. Rapid eye movement sleep behavior disorder--diagnostik, årsager og behandling

    DEFF Research Database (Denmark)

    Zoetmulder, Marielle; Jennum, Poul Jørgen

    2009-01-01

    Rapid eye movement (REM) sleep behaviour disorder (RBD) is characterized by loss of REM sleep and related electromyographic atonia with marked muscular activity and dream enactment behaviour. RBD is seen in 0.5% of the population. It occurs in an idiopathic form and secondarily to medical...

  2. Disrupted rapid eye movement sleep predicts poor declarative memory performance in post-traumatic stress disorder.

    Science.gov (United States)

    Lipinska, Malgorzata; Timol, Ridwana; Kaminer, Debra; Thomas, Kevin G F

    2014-06-01

    Successful memory consolidation during sleep depends on healthy slow-wave and rapid eye movement sleep, and on successful transition across sleep stages. In post-traumatic stress disorder, sleep is disrupted and memory is impaired, but relations between these two variables in the psychiatric condition remain unexplored. We examined whether disrupted sleep, and consequent disrupted memory consolidation, is a mechanism underlying declarative memory deficits in post-traumatic stress disorder. We recruited three matched groups of participants: post-traumatic stress disorder (n = 16); trauma-exposed non-post-traumatic stress disorder (n = 15); and healthy control (n = 14). They completed memory tasks before and after 8 h of sleep. We measured sleep variables using sleep-adapted electroencephalography. Post-traumatic stress disorder-diagnosed participants experienced significantly less sleep efficiency and rapid eye movement sleep percentage, and experienced more awakenings and wake percentage in the second half of the night than did participants in the other two groups. After sleep, post-traumatic stress disorder-diagnosed participants retained significantly less information on a declarative memory task than controls. Rapid eye movement percentage, wake percentage and sleep efficiency correlated with retention of information over the night. Furthermore, lower rapid eye movement percentage predicted poorer retention in post-traumatic stress disorder-diagnosed individuals. Our results suggest that declarative memory consolidation is disrupted during sleep in post-traumatic stress disorder. These data are consistent with theories suggesting that sleep benefits memory consolidation via predictable neurobiological mechanisms, and that rapid eye movement disruption is more than a symptom of post-traumatic stress disorder. © 2014 European Sleep Research Society.

  3. Relevance of new multispectral imagery for assessing tropical forest disturbance: RapidEye and WorldView-2

    CSIR Research Space (South Africa)

    Cho, Moses A

    2012-11-01

    Full Text Available The aims of this study were to assess utility of RapidEye imagery for predicting leaf nitrogen concentration and evaluate the effects of forest fragmentation on leaf nitrogen distribution in the Dukuduku forest, KwaZulu Natal, South Africa. RapidEye...

  4. Rapid eye movements during sleep in mice: High trait-like stability qualifies rapid eye movement density for characterization of phenotypic variation in sleep patterns of rodents

    Directory of Open Access Journals (Sweden)

    Fulda Stephany

    2011-11-01

    Full Text Available Abstract Background In humans, rapid eye movements (REM density during REM sleep plays a prominent role in psychiatric diseases. Especially in depression, an increased REM density is a vulnerability marker for depression. In clinical practice and research measurement of REM density is highly standardized. In basic animal research, almost no tools are available to obtain and systematically evaluate eye movement data, although, this would create increased comparability between human and animal sleep studies. Methods We obtained standardized electroencephalographic (EEG, electromyographic (EMG and electrooculographic (EOG signals from freely behaving mice. EOG electrodes were bilaterally and chronically implanted with placement of the electrodes directly between the musculus rectus superior and musculus rectus lateralis. After recovery, EEG, EMG and EOG signals were obtained for four days. Subsequent to the implantation process, we developed and validated an Eye Movement scoring in Mice Algorithm (EMMA to detect REM as singularities of the EOG signal, based on wavelet methodology. Results The distribution of wakefulness, non-REM (NREM sleep and rapid eye movement (REM sleep was typical of nocturnal rodents with small amounts of wakefulness and large amounts of NREM sleep during the light period and reversed proportions during the dark period. REM sleep was distributed correspondingly. REM density was significantly higher during REM sleep than NREM sleep. REM bursts were detected more often at the end of the dark period than the beginning of the light period. During REM sleep REM density showed an ultradian course, and during NREM sleep REM density peaked at the beginning of the dark period. Concerning individual eye movements, REM duration was longer and amplitude was lower during REM sleep than NREM sleep. The majority of single REM and REM bursts were associated with micro-arousals during NREM sleep, but not during REM sleep. Conclusions Sleep

  5. Research progress on the pathogenesis of rapid eye movement sleep behavior disorder and neurodegenerative diseases

    Directory of Open Access Journals (Sweden)

    Hai-yang JIANG

    2017-10-01

    Full Text Available Rapid eye movement sleep behavior disorder (RBD is a sleep disorder characterized by the disappearance of muscle relaxation and enacting one's dreams during rapid eye movement (REM, with most of the dreams being violent or aggressive. Prevalence of RBD, based on population, is 0.38%-2.01%, but it becomes much higher in patients with neurodegenerative diseases, especially α - synucleinopathies. RBD may herald the emergence of α-synucleinopathies by decades, thus it may be used as an effective early marker of neurodegenerative diseases. In this review, we summarized the progress on the pathogenesis of RBD and its relationship with neurodegenerative diseases. DOI: 10.3969/j.issn.1672-6731.2017.10.003

  6. Predicting stem borer density in maize using RapidEye data and generalized linear models

    Science.gov (United States)

    Abdel-Rahman, Elfatih M.; Landmann, Tobias; Kyalo, Richard; Ong'amo, George; Mwalusepo, Sizah; Sulieman, Saad; Ru, Bruno Le

    2017-05-01

    Average maize yield in eastern Africa is 2.03 t ha-1 as compared to global average of 6.06 t ha-1 due to biotic and abiotic constraints. Amongst the biotic production constraints in Africa, stem borers are the most injurious. In eastern Africa, maize yield losses due to stem borers are currently estimated between 12% and 21% of the total production. The objective of the present study was to explore the possibility of RapidEye spectral data to assess stem borer larva densities in maize fields in two study sites in Kenya. RapidEye images were acquired for the Bomet (western Kenya) test site on the 9th of December 2014 and on 27th of January 2015, and for Machakos (eastern Kenya) a RapidEye image was acquired on the 3rd of January 2015. Five RapidEye spectral bands as well as 30 spectral vegetation indices (SVIs) were utilized to predict per field maize stem borer larva densities using generalized linear models (GLMs), assuming Poisson ('Po') and negative binomial ('NB') distributions. Root mean square error (RMSE) and ratio prediction to deviation (RPD) statistics were used to assess the models performance using a leave-one-out cross-validation approach. The Zero-inflated NB ('ZINB') models outperformed the 'NB' models and stem borer larva densities could only be predicted during the mid growing season in December and early January in both study sites, respectively (RMSE = 0.69-1.06 and RPD = 8.25-19.57). Overall, all models performed similar when all the 30 SVIs (non-nested) and only the significant (nested) SVIs were used. The models developed could improve decision making regarding controlling maize stem borers within integrated pest management (IPM) interventions.

  7. The golden age of rapid eye movement sleep discoveries. 1. Lucretius--1964.

    Science.gov (United States)

    Gottesmann, C

    2001-10-01

    Although there were several premonitory signs of a sleep stage with dreaming, it was only in 1953 that such a stage was identified with certainty. This paper analyses the observations and research related to this dreaming stage (rapid eye movement sleep) until 1964. During these 11 years of research, the main psychological and physiological characteristics of this sleep stage were first described. Where the few results or discussions were later questioned, today's current state of knowledge is briefly outlined.

  8. A single-question screen for rapid eye movement sleep behavior disorder

    DEFF Research Database (Denmark)

    Postuma, Ronald B; Arnulf, Isabelle; Hogl, Birgit

    2012-01-01

    Idiopathic rapid eye movement (REM) sleep behavior disorder (RBD) is a parasomnia that is an important risk factor for Parkinson's disease (PD) and Lewy body dementia. Its prevalence is unknown. One barrier to determining prevalence is that current screening tools are too long for large......-scale epidemiologic surveys. Therefore, we designed the REM Sleep Behavior Disorder Single-Question Screen (RBD1Q), a screening question for dream enactment with a simple yes/no response....

  9. Clinical features of Parkinson’s disease with and without rapid eye movement sleep behavior disorder

    OpenAIRE

    Liu, Ye; Zhu, Xiao-Ying; Zhang, Xiao-Jin; Kuo, Sheng-Han; Ondo, William G.; Wu, Yun-Cheng

    2017-01-01

    Background Rapid eye movement sleep behavior disorder (RBD) and Parkinson’s disease (PD) are two distinct clinical diseases but they share some common pathological and anatomical characteristics. This study aims to confirm the clinical features of RBD in Chinese PD patients. Methods One hundred fifty PD patients were enrolled from the Parkinson`s disease and Movement Disorders Center in  Department of Neurology, Shanghai General Hospital from January 2013 to August 2014. This study examined P...

  10. Crop Type Classification Using Vegetation Indices of RapidEye Imagery

    Science.gov (United States)

    Ustuner, M.; Sanli, F. B.; Abdikan, S.; Esetlili, M. T.; Kurucu, Y.

    2014-09-01

    Cutting-edge remote sensing technology has a significant role for managing the natural resources as well as the any other applications about the earth observation. Crop monitoring is the one of these applications since remote sensing provides us accurate, up-to-date and cost-effective information about the crop types at the different temporal and spatial resolution. In this study, the potential use of three different vegetation indices of RapidEye imagery on crop type classification as well as the effect of each indices on classification accuracy were investigated. The Normalized Difference Vegetation Index (NDVI), the Green Normalized Difference Vegetation Index (GNDVI), and the Normalized Difference Red Edge Index (NDRE) are the three vegetation indices used in this study since all of these incorporated the near-infrared (NIR) band. RapidEye imagery is highly demanded and preferred for agricultural and forestry applications since it has red-edge and NIR bands. The study area is located in Aegean region of Turkey. Radial Basis Function (RBF) kernel was used here for the Support Vector Machines (SVMs) classification. Original bands of RapidEye imagery were excluded and classification was performed with only three vegetation indices. The contribution of each indices on image classification accuracy was also tested with single band classification. Highest classification accuracy of 87, 46 % was obtained using three vegetation indices. This obtained classification accuracy is higher than the classification accuracy of any dual-combination of these vegetation indices. Results demonstrate that NDRE has the highest contribution on classification accuracy compared to the other vegetation indices and the RapidEye imagery can get satisfactory results of classification accuracy without original bands.

  11. Caffeine increases the velocity of rapid eye movements in unfatigued humans.

    Science.gov (United States)

    Connell, Charlotte J W; Thompson, Benjamin; Turuwhenua, Jason; Hess, Robert F; Gant, Nicholas

    2017-08-01

    Caffeine is a widely used dietary stimulant that can reverse the effects of fatigue on cognitive, motor and oculomotor function. However, few studies have examined the effect of caffeine on the oculomotor system when homeostasis has not been disrupted by physical fatigue. This study examined the influence of a moderate dose of caffeine on oculomotor control and visual perception in participants who were not fatigued. Within a placebo-controlled crossover design, 13 healthy adults ingested caffeine (5 mg·kg -1 body mass) and were tested over 3 h. Eye movements, including saccades, smooth pursuit and optokinetic nystagmus, were measured using infrared oculography. Caffeine was associated with higher peak saccade velocities (472 ± 60° s -1 ) compared to placebo (455 ± 62° s -1 ). Quick phases of optokinetic nystagmus were also significantly faster with caffeine, whereas pursuit eye movements were unchanged. Non-oculomotor perceptual tasks (global motion and global orientation processing) were unaffected by caffeine. These results show that oculomotor control is modulated by a moderate dose of caffeine in unfatigued humans. These effects are detectable in the kinematics of rapid eye movements, whereas pursuit eye movements and visual perception are unaffected. Oculomotor functions may be sensitive to changes in central catecholamines mediated via caffeine's action as an adenosine antagonist, even when participants are not fatigued.

  12. Rapid, low-cost photogrammetry to monitor volcanic eruptions: an example from Mount St. Helens, Washington, USA

    Science.gov (United States)

    Diefenbach, Angela K.; Crider, Juliet G.; Schilling, Steve P.; Dzurisin, Daniel

    2012-01-01

    We describe a low-cost application of digital photogrammetry using commercially available photogrammetric software and oblique photographs taken with an off-the-shelf digital camera to create sequential digital elevation models (DEMs) of a lava dome that grew during the 2004–2008 eruption of Mount St. Helens (MSH) volcano. Renewed activity at MSH provided an opportunity to devise and test this method, because it could be validated against other observations of this well-monitored volcano. The datasets consist of oblique aerial photographs (snapshots) taken from a helicopter using a digital single-lens reflex camera. Twelve sets of overlapping digital images of the dome taken during 2004–2007 were used to produce DEMs and to calculate lava dome volumes and extrusion rates. Analyses of the digital images were carried out using photogrammetric software to produce three-dimensional coordinates of points identified in multiple photos. The evolving morphology of the dome was modeled by comparing successive DEMs. Results were validated by comparison to volume measurements derived from traditional vertical photogrammetric surveys by the US Geological Survey Cascades Volcano Observatory. Our technique was significantly less expensive and required less time than traditional vertical photogrammetric techniques; yet, it consistently yielded volume estimates within 5% of the traditional method. This technique provides an inexpensive, rapid assessment tool for tracking lava dome growth or other topographic changes at restless volcanoes.

  13. Mapping Submerged Aquatic Vegetation Using RapidEye Satellite Data: The Example of Lake Kummerow (Germany

    Directory of Open Access Journals (Sweden)

    Christine Fritz

    2017-07-01

    Full Text Available Submersed aquatic vegetation (SAV is sensitive to changes in environmental conditions and plays an important role as a long-term indictor for the trophic state of freshwater lakes. Variations in water level height, nutrient condition, light availability and water temperature affect the growth and species composition of SAV. Detailed information about seasonal variations in littoral bottom coverage are still unknown, although these effects are expected to mask climate change-related long-term changes, as derived by snapshots of standard monitoring methods included in the European Water Framework Directive. Remote sensing offers concepts to map SAV quickly, within large areas, and at short intervals. This study analyses the potential of a semi-empirical method to map littoral bottom coverage by a multi-seasonal approach. Depth-invariant indices were calculated for four Atmospheric & Topographic Correction (ATCOR2 atmospheric corrected RapidEye data sets acquired at Lake Kummerow, Germany, between June and August 2015. RapidEye data evaluation was supported by in situ measurements of the diffuse attenuation coefficient of the water column and bottom reflectance. The processing chain was able to differentiate between SAV and sandy sediment. The successive increase of SAV coverage from June to August was correctly monitored. Comparisons with in situ and Google Earth imagery revealed medium accuracies (kappa coefficient = 0.61, overall accuracy = 72.2%. The analysed time series further revealed how water constituents and temporary surface phenomena such as sun glint or algal blooms influence the identification success of lake bottom substrates. An abundant algal bloom biased the interpretability of shallow water substrate such that a differentiation of sediments and SAV patches failed completely. Despite the documented limitations, mapping of SAV using RapidEye seems possible, even in eutrophic lakes.

  14. Relationships between Rapid Eye Movement Sleep Behavior Disorder and Neurodegenerative Diseases: Clinical Assessments, Biomarkers, and Treatment

    Science.gov (United States)

    Li, Min; Wang, Li; Liu, Jiang-Hong; Zhan, Shu-Qin

    2018-01-01

    Objective: Rapid eye movement sleep behavior disorder (RBD) is characterized by dream enactment and loss of muscle atonia during rapid eye movement sleep. RBD is closely related to α-synucleinopathies including Parkinson's disease, dementia with Lewy bodies, and multiple system atrophy. Many studies have investigated the markers of imaging and neurophysiological, genetic, cognitive, autonomic function of RBD and their predictive value for neurodegenerative diseases. This report reviewed the progress of these studies and discussed their limitations and future research directions. Data Sources: Using the combined keywords: “RBD”, “neurodegenerative disease”, “Parkinson disease”, and “magnetic resonance imaging”, the PubMed/MEDLINE literature search was conducted up to January 1, 2018. Study Selection: A total of 150 published articles were initially identified citations. Of the 150 articles, 92 articles were selected after further detailed review. This study referred to all the important English literature in full. Results: Single-nucleotide polymorphisms in SCARB2 (rs6812193) and MAPT (rs12185268) were significantly associated with RBD. The olfactory loss, autonomic dysfunction, marked electroencephalogram slowing during both wakefulness and rapid eye movement sleep, and cognitive impairments were potential predictive markers for RBD conversion to neurodegenerative diseases. Traditional structural imaging studies reported relatively inconsistent results, whereas reduced functional connectivity between the left putamen and substantia nigra and dopamine transporter uptake demonstrated by functional imaging techniques were relatively consistent findings. Conclusions: More longitudinal studies should be conducted to evaluate the predictive value of biomarkers of RBD. Moreover, because the glucose and dopamine metabolisms are not specific for assessing cognitive cognition, the molecular metabolism directly related to cognition should be investigated

  15. Rapid eye movement sleep behavior disorder--diagnostik, årsager og behandling

    DEFF Research Database (Denmark)

    Zoetmulder, Marielle; Jennum, Poul Jørgen

    2009-01-01

    Rapid eye movement (REM) sleep behaviour disorder (RBD) is characterized by loss of REM sleep and related electromyographic atonia with marked muscular activity and dream enactment behaviour. RBD is seen in 0.5% of the population. It occurs in an idiopathic form and secondarily to medical...... and neurological disease. RBD is related to brainstem pathology. Furthermore, it is increasingly recognized that RBD is frequently related to Parkinsonian disorders and narcolepsy. This article reviews recent knowledge about RBD with focus on the diagnostic process and management....

  16. Rapid Eye Movement Sleep Behavior Disorder in Paraneoplastic Cerebellar Degeneration: Improvement with Immunotherapy.

    Science.gov (United States)

    Vale, Thiago Cardoso; Fernandes do Prado, Lucila Bizari; do Prado, Gilmar Fernandes; Povoas Barsottini, Orlando Graziani; Pedroso, José Luiz

    2016-01-01

    To report two female patients with paraneoplastic cerebellar degeneration (PCD) related to breast cancer that presented with rapid eye movement-sleep behavior disorder (RBD) and improved sleep symptoms with immunotherapy. The two patients were evaluated through clinical scale and polysomnography before and after therapy with intravenous immunoglobulin. RBD was successfully treated with immunotherapy in both patients. Score on the RBD screening questionnaire dropped from 10 to 1 or 0, allied with the normalization of polysomnographic findings. A marked improvement in RBD after immunotherapy in PCD raises the hypothesis that secondary RBD may be an immune-mediated sleep disorder. © 2016 Associated Professional Sleep Societies, LLC.

  17. RapidEye constellation relative radiometric accuracy measurement using lunar images

    Science.gov (United States)

    Steyn, Joe; Tyc, George; Beckett, Keith; Hashida, Yoshi

    2009-09-01

    The RapidEye constellation includes five identical satellites in Low Earth Orbit (LEO). Each satellite has a 5-band (blue, green, red, red-edge and near infrared (NIR)) multispectral imager at 6.5m GSD. A three-axes attitude control system allows pointing the imager of each satellite at the Moon during lunations. It is therefore possible to image the Moon from near identical viewing geometry within a span of 80 minutes with each one of the imagers. Comparing the radiometrically corrected images obtained from each band and each satellite allows a near instantaneous relative radiometric accuracy measurement and determination of relative gain changes between the five imagers. A more traditional terrestrial vicarious radiometric calibration program has also been completed by MDA on RapidEye. The two components of this program provide for spatial radiometric calibration ensuring that detector-to-detector response remains flat, while a temporal radiometric calibration approach has accumulated images of specific dry dessert calibration sites. These images are used to measure the constellation relative radiometric response and make on-ground gain and offset adjustments in order to maintain the relative accuracy of the constellation within +/-2.5%. A quantitative comparison between the gain changes measured by the lunar method and the terrestrial temporal radiometric calibration method is performed and will be presented.

  18. Regional estimation of savanna grass nitrogen using the red-edge band of the RapidEye sensor

    CSIR Research Space (South Africa)

    Ramoelo, Abel

    2012-10-01

    Full Text Available recent high resolution spaceborne multispectral sensor (i.e. RapidEye) in the Kruger National Park (KNP) and its surrounding areas, South Africa. The RapidEyesensor contains five spectral bands in the visible-to-near infrared (VNIR), including a red...

  19. Using a slit lamp-mounted digital high-speed camera for dynamic observation of phakic lenses during eye movements: a pilot study

    Directory of Open Access Journals (Sweden)

    Leitritz MA

    2014-07-01

    Full Text Available Martin Alexander Leitritz, Focke Ziemssen, Karl Ulrich Bartz-Schmidt, Bogomil Voykov Centre for Ophthalmology, University Eye Hospital, Eberhard Karls University of Tübingen, Tübingen, Germany Purpose: To evaluate a digital high-speed camera combined with digital morphometry software for dynamic measurements of phakic intraocular lens movements to observe kinetic influences, particularly in fast direction changes and at lateral end points. Materials and methods: A high-speed camera taking 300 frames per second observed movements of eight iris-claw intraocular lenses and two angle-supported intraocular lenses. Standardized saccades were performed by the patients to trigger mass inertia with lens position changes. Freeze images with maximum deviation were used for digital software-based morphometry analysis with ImageJ.Results: Two eyes from each of five patients (median age 32 years, range 28–45 years without findings other than refractive errors were included. The high-speed images showed sufficient usability for further morphometric processing. In the primary eye position, the median decentrations downward and in a lateral direction were -0.32 mm (range -0.69 to 0.024 and 0.175 mm (range -0.37 to 0.45, respectively. Despite the small sample size of asymptomatic patients, we found a considerable amount of lens dislocation. The median distance amplitude during eye movements was 0.158 mm (range 0.02–0.84. There was a slight positive corrlation (r=0.39, P<0.001 between the grade of deviation in the primary position and the distance increase triggered by movements.Conclusion: With the use of a slit lamp-mounted high-speed camera system and morphometry software, observation and objective measurements of iris-claw intraocular lenses and angle-supported intraocular lenses movements seem to be possible. Slight decentration in the primary position might be an indicator of increased lens mobility during kinetic stress during eye movements

  20. The inappropriate occurrence of rapid eye movement sleep in narcolepsy is not due to a defect in homeostatic regulation of rapid eye movement sleep.

    Science.gov (United States)

    Roman, Alexis; Meftah, Soraya; Arthaud, Sébastien; Luppi, Pierre-Hervé; Peyron, Christelle

    2018-06-01

    Narcolepsy type 1 is a disabling disorder with four primary symptoms: excessive-daytime-sleepiness, cataplexy, hypnagogic hallucinations, and sleep paralysis. The later three symptoms together with a short rapid eye movement (REM) sleep latency have suggested impairment in REM sleep homeostatic regulation with an enhanced propensity for (i.e. tendency to enter) REM sleep. To test this hypothesis, we challenged REM sleep homeostatic regulation in a recognized model of narcolepsy, the orexin knock-out (Orex-KO) mice and their wild-type (WT) littermates. We first performed 48 hr of REM sleep deprivation using the classic small-platforms-over-water method. We found that narcoleptic mice are similarly REM sleep deprived to WT mice. Although they had shorter sleep latency, Orex-KO mice recovered similarly to WT during the following 10 hr of recovery. Interestingly, Orex-KO mice also had cataplexy episodes immediately after REM sleep deprivation, anticipating REM sleep rebound, at a time of day when cataplexy does not occur in baseline condition. We then evaluated REM sleep propensity using our new automated method of deprivation that performs a specific and efficient REM sleep deprivation. We showed that REM sleep propensity is similar during light phase in Orex-KO and WT mice. However, during the dark phase, REM sleep propensity was not suppressed in Orex-KO mice when hypocretin/orexin neuropeptides are normally released. Altogether our data suggest that in addition to the well-known wake-promoting role of hypocretin/orexin, these neuropeptides would also suppress REM sleep. Therefore, hypocretin/orexin deficiency would facilitate the occurrence of REM sleep at any time of day in an opportunistic manner as seen in human narcolepsy.

  1. The improvement of movement and speech during rapid eye movement sleep behaviour disorder in multiple system atrophy.

    Science.gov (United States)

    De Cock, Valérie Cochen; Debs, Rachel; Oudiette, Delphine; Leu, Smaranda; Radji, Fatai; Tiberge, Michel; Yu, Huan; Bayard, Sophie; Roze, Emmanuel; Vidailhet, Marie; Dauvilliers, Yves; Rascol, Olivier; Arnulf, Isabelle

    2011-03-01

    Multiple system atrophy is an atypical parkinsonism characterized by severe motor disabilities that are poorly levodopa responsive. Most patients develop rapid eye movement sleep behaviour disorder. Because parkinsonism is absent during rapid eye movement sleep behaviour disorder in patients with Parkinson's disease, we studied the movements of patients with multiple system atrophy during rapid eye movement sleep. Forty-nine non-demented patients with multiple system atrophy and 49 patients with idiopathic Parkinson's disease were interviewed along with their 98 bed partners using a structured questionnaire. They rated the quality of movements, vocal and facial expressions during rapid eye movement sleep behaviour disorder as better than, equal to or worse than the same activities in an awake state. Sleep and movements were monitored using video-polysomnography in 22/49 patients with multiple system atrophy and in 19/49 patients with Parkinson's disease. These recordings were analysed for the presence of parkinsonism and cerebellar syndrome during rapid eye movement sleep movements. Clinical rapid eye movement sleep behaviour disorder was observed in 43/49 (88%) patients with multiple system atrophy. Reports from the 31/43 bed partners who were able to evaluate movements during sleep indicate that 81% of the patients showed some form of improvement during rapid eye movement sleep behaviour disorder. These included improved movement (73% of patients: faster, 67%; stronger, 52%; and smoother, 26%), improved speech (59% of patients: louder, 55%; more intelligible, 17%; and better articulated, 36%) and normalized facial expression (50% of patients). The rate of improvement was higher in Parkinson's disease than in multiple system atrophy, but no further difference was observed between the two forms of multiple system atrophy (predominant parkinsonism versus cerebellar syndrome). Video-monitored movements during rapid eye movement sleep in patients with multiple system

  2. Older drivers and rapid deceleration events: Salisbury Eye Evaluation Driving Study.

    Science.gov (United States)

    Keay, Lisa; Munoz, Beatriz; Duncan, Donald D; Hahn, Daniel; Baldwin, Kevin; Turano, Kathleen A; Munro, Cynthia A; Bandeen-Roche, Karen; West, Sheila K

    2013-09-01

    Drivers who rapidly change speed while driving may be more at risk for a crash. We sought to determine the relationship of demographic, vision, and cognitive variables with episodes of rapid decelerations during five days of normal driving in a cohort of older drivers. In the Salisbury Eye Evaluation Driving Study, 1425 older drivers aged 67-87 were recruited from the Maryland Motor Vehicle Administration's rolls for licensees in Salisbury, Maryland. Participants had several measures of vision tested: visual acuity, contrast sensitivity, visual fields, and the attentional visual field. Participants were also tested for various domains of cognitive function including executive function, attention, psychomotor speed, and visual search. A custom created driving monitoring system (DMS) was used to capture rapid deceleration events (RDEs), defined as at least 350 milli-g deceleration, during a five day period of monitoring. The rate of RDE per mile driven was modeled using a negative binomial regression model with an offset of the logarithm of the number of miles driven. We found that 30% of older drivers had one or more RDE during a five day period, and of those, about 1/3 had four or more. The rate of RDE per mile driven was highest for those drivers drivingRDE's were more likely to have better scores in cognitive tests of psychomotor speed and visual search, and have faster brake reaction time. Further, greater average speed and maximum speed per driving segment was protective against RDE events. In conclusion, contrary to our hypothesis, older drivers who perform rapid decelerations tend to be more "fit", with better measures of vision and cognition compared to those who do not have events of rapid deceleration. Copyright © 2012 Elsevier Ltd. All rights reserved.

  3. Rapid Eye Movements (REMs) and visual dream recall in both congenitally blind and sighted subjects

    Science.gov (United States)

    Bértolo, Helder; Mestre, Tiago; Barrio, Ana; Antona, Beatriz

    2017-08-01

    Our objective was to evaluate rapid eye movements (REMs) associated with visual dream recall in sighted subjects and congenital blind. During two consecutive nights polysomnographic recordings were performed at subjects home. REMs were detected by visual inspection on both EOG channels (EOG-H, EOG-V) and further classified as occurring isolated or in bursts. Dream recall was defined by the existence of a dream report. The two groups were compared using t-test and also the two-way ANOVA and a post-hoc Fisher test (for the features diagnosis (blind vs. sighted) and dream recall (yes or no) as a function of time). The average of REM awakenings per subject and the recall ability were identical in both groups. CB had a lower REM density than CS; the same applied to REM bursts and isolated eye movements. In the two-way ANOVA, REM bursts and REM density were significantly different for positive dream recall, mainly for the CB group and for diagnosis; furthermore for both features significant results were obtained for the interaction of time, recall and diagnosis; the interaction of recall and time was however, stronger. In line with previous findings the data show that blind have lower REMs density. However the ability of dream recall in congenitally blind and sighted controls is identical. In both groups visual dream recall is associated with an increase in REM bursts and density. REM bursts also show differences in the temporal profile. REM visual dream recall is associated with increased REMs activity.

  4. Urotensin II modulates rapid eye movement sleep through activation of brainstem cholinergic neurons

    DEFF Research Database (Denmark)

    Huitron-Resendiz, Salvador; Kristensen, Morten Pilgaard; Sánchez-Alavez, Manuel

    2005-01-01

    administration of UII into the PPT nucleus increases REM sleep without inducing changes in the cortical blood flow. Intracerebroventricular injection of UII enhances both REM sleep and wakefulness and reduces slow-wave sleep 2. Intracerebroventricular, but not local, administration of UII increases cortical...... dorsal tegmental nuclei. This distribution suggests that the UII system is involved in functions regulated by acetylcholine, such as the sleep-wake cycle. Here, we tested the hypothesis that UII influences cholinergic PPT neuron activity and alters rapid eye movement (REM) sleep patterns in rats. Local...... synaptic transmission because it persisted in the presence of TTX and antagonists of ionotropic glutamate, GABA, and glycine receptors. Collectively, these results suggest that UII plays a role in the regulation of REM sleep independently of its cerebrovascular actions by directly activating cholinergic...

  5. Rapid eye movement sleep behavior disorder as an outlier detection problem

    DEFF Research Database (Denmark)

    Kempfner, Jacob; Sørensen, Gertrud Laura; Nikolic, M.

    2014-01-01

    OBJECTIVE: Idiopathic rapid eye movement (REM) sleep behavior disorder is a strong early marker of Parkinson's disease and is characterized by REM sleep without atonia and/or dream enactment. Because these measures are subject to individual interpretation, there is consequently need...... for quantitative methods to establish objective criteria. This study proposes a semiautomatic algorithm for the early detection of Parkinson's disease. This is achieved by distinguishing between normal REM sleep and REM sleep without atonia by considering muscle activity as an outlier detection problem. METHODS......: Sixteen healthy control subjects, 16 subjects with idiopathic REM sleep behavior disorder, and 16 subjects with periodic limb movement disorder were enrolled. Different combinations of five surface electromyographic channels, including the EOG, were tested. A muscle activity score was automatically...

  6. Human regional cerebral blood flow during rapid-eye-movement sleep

    DEFF Research Database (Denmark)

    Madsen, P L; Holm, S; Vorstrup, S

    1991-01-01

    Owing to the coupling between CBF and neuronal activity, regional CBF is a reflection of neural activity in different brain regions. In this study we measured regional CBF during polysomnographically well-defined rapid-eye-movement (REM) sleep by the use of single photon emission computerized...... tomography and the new tracer 99mTc-dl-hexamethylpropyleneamine. Eleven healthy volunteers aged between 22 and 27 years were studied. CBF was measured on separate nights during REM sleep and during EEG-verified wakefulness. On awakening from REM sleep, all subjects reported visual dreams. During REM sleep...... dream experiences. On the other hand, the reduced involvement of the inferior frontal cortex observed during REM sleep might explain the poor temporal organization and bizarreness often experienced in dreams....

  7. Remifentanil inhibits rapid eye movement sleep but not the nocturnal melatonin surge in humans.

    Science.gov (United States)

    Bonafide, Christopher P; Aucutt-Walter, Natalie; Divittore, Nicole; King, Tonya; Bixler, Edward O; Cronin, Arthur J

    2008-04-01

    Postoperative patients are sleep deprived. Opioids, commonly administered for postoperative pain control, are often mistakenly considered inducers of naturally occurring sleep. This study describes the effect of the opioid remifentanil on nocturnal sleep in healthy volunteers. In addition, this study tests the hypothesis that opioid-induced sleep disturbance is caused by a circadian pacemaker disturbance, reflected by suppressed nocturnal plasma concentration of melatonin. Polysomnography was performed in 10 volunteers from 11:00 pm to 7:00 am for four nights at 6-day intervals. On two nights, remifentanil (0.01-0.04 microg x kg x min) was infused from 10:30 pm to 7:00 am, and either a placebo capsule or 3.0 mg melatonin was administered at 10:30 pm. On two additional nights, saline was infused, and the placebo or melatonin capsules were administered at 10:30 pm. Blood was drawn at 12:00 am, 3:00 am, and 6:00 am to measure the plasma concentration of melatonin and cortisol. A repeated-measures analysis of variance model was used to determine the effect of remifentanil on sleep stages, the effect of remifentanil on the plasma concentration of melatonin, and the effect of exogenous melatonin on remifentanil-induced sleep disturbance. Remifentanil inhibited rapid eye movement sleep (14.1 +/- 7.2% to 3.9 +/- 6.9%). The amount of slow wave sleep decreased from 6.8 +/- 7.6% to 3.2 +/- 6.1%, but this decrease was not statistically significant. Remifentanil did not decrease melatonin concentration. Melatonin administration did not prevent remifentanil-induced sleep disturbance. An overnight constant infusion of remifentanil inhibits rapid eye movement sleep without suppressing the nocturnal melatonin surge.

  8. Electroencephalographic findings related with mild cognitive impairment in idiopathic rapid eye movement sleep behavior disorder.

    Science.gov (United States)

    Sasai, Taeko; Matsuura, Masato; Inoue, Yuichi

    2013-12-01

    Mild cognitive impairment (MCI) and electroencephalographic (EEG) slowing have been reported as common findings of idiopathic rapid eye movement (REM) sleep behavior disorder (iRBD) and α-synucleinopathies. The objective of this study is to clarify the relation between MCI and physiological markers in iRBD. Cross-sectional study. Yoyogi Sleep Disorder Center. Thirty-one patients with iRBD including 17 younger patients with iRBD (younger than 70 y) and 17 control patients for the younger patients with iRBD. N/A. Montreal Cognitive Assessment (MoCA) and n-polysomnogram (PSG) were conducted of all participants. In patients with iRBD, the factors associated with MCI were explored among parameters of REM sleep without atonia (RWA), score of Sniffin' Sticks Test (threshold-discrimination-identification [TDI] score), RBD morbidity, and RBD severity evaluated with the Japanese version of the RBD questionnaire (RBDQ-JP). The younger iRBD group showed significantly lower alpha power during wake and lower MoCA score than the age-matched control group. MCI was detected in 13 of 17 patients (76.5%) on MoCA in this group. Among patients wtih iRBD, the MoCA score negatively correlated with age, proportion of slow wave sleep, TDI score, and EEG spectral power. Multiple regression analysis provided the following equation: MoCA score = 50.871-0.116*age -5.307*log (δ power during REM sleep) + 0.086*TDI score (R² = 0.598, P sleep), and 0.357 for TDI score (F = 9.900, P sleep and olfactory dysfunction, was revealed to be associated with cognitive decline in idiopathic rapid eye movement sleep behavior disorder.

  9. Maize Cropping Systems Mapping Using RapidEye Observations in Agro-Ecological Landscapes in Kenya.

    Science.gov (United States)

    Richard, Kyalo; Abdel-Rahman, Elfatih M; Subramanian, Sevgan; Nyasani, Johnson O; Thiel, Michael; Jozani, Hosein; Borgemeister, Christian; Landmann, Tobias

    2017-11-03

    Cropping systems information on explicit scales is an important but rarely available variable in many crops modeling routines and of utmost importance for understanding pests and disease propagation mechanisms in agro-ecological landscapes. In this study, high spatial and temporal resolution RapidEye bio-temporal data were utilized within a novel 2-step hierarchical random forest (RF) classification approach to map areas of mono- and mixed maize cropping systems. A small-scale maize farming site in Machakos County, Kenya was used as a study site. Within the study site, field data was collected during the satellite acquisition period on general land use/land cover (LULC) and the two cropping systems. Firstly, non-cropland areas were masked out from other land use/land cover using the LULC mapping result. Subsequently an optimized RF model was applied to the cropland layer to map the two cropping systems (2nd classification step). An overall accuracy of 93% was attained for the LULC classification, while the class accuracies (PA: producer's accuracy and UA: user's accuracy) for the two cropping systems were consistently above 85%. We concluded that explicit mapping of different cropping systems is feasible in complex and highly fragmented agro-ecological landscapes if high resolution and multi-temporal satellite data such as 5 m RapidEye data is employed. Further research is needed on the feasibility of using freely available 10-20 m Sentinel-2 data for wide-area assessment of cropping systems as an important variable in numerous crop productivity models.

  10. Maize Cropping Systems Mapping Using RapidEye Observations in Agro-Ecological Landscapes in Kenya

    Directory of Open Access Journals (Sweden)

    Kyalo Richard

    2017-11-01

    Full Text Available Cropping systems information on explicit scales is an important but rarely available variable in many crops modeling routines and of utmost importance for understanding pests and disease propagation mechanisms in agro-ecological landscapes. In this study, high spatial and temporal resolution RapidEye bio-temporal data were utilized within a novel 2-step hierarchical random forest (RF classification approach to map areas of mono- and mixed maize cropping systems. A small-scale maize farming site in Machakos County, Kenya was used as a study site. Within the study site, field data was collected during the satellite acquisition period on general land use/land cover (LULC and the two cropping systems. Firstly, non-cropland areas were masked out from other land use/land cover using the LULC mapping result. Subsequently an optimized RF model was applied to the cropland layer to map the two cropping systems (2nd classification step. An overall accuracy of 93% was attained for the LULC classification, while the class accuracies (PA: producer’s accuracy and UA: user’s accuracy for the two cropping systems were consistently above 85%. We concluded that explicit mapping of different cropping systems is feasible in complex and highly fragmented agro-ecological landscapes if high resolution and multi-temporal satellite data such as 5 m RapidEye data is employed. Further research is needed on the feasibility of using freely available 10–20 m Sentinel-2 data for wide-area assessment of cropping systems as an important variable in numerous crop productivity models.

  11. Memory Reactivation during Rapid Eye Movement Sleep Promotes Its Generalization and Integration in Cortical Stores

    Science.gov (United States)

    Sterpenich, Virginie; Schmidt, Christina; Albouy, Geneviève; Matarazzo, Luca; Vanhaudenhuyse, Audrey; Boveroux, Pierre; Degueldre, Christian; Leclercq, Yves; Balteau, Evelyne; Collette, Fabienne; Luxen, André; Phillips, Christophe; Maquet, Pierre

    2014-01-01

    Study Objectives: Memory reactivation appears to be a fundamental process in memory consolidation. In this study we tested the influence of memory reactivation during rapid eye movement (REM) sleep on memory performance and brain responses at retrieval in healthy human participants. Participants: Fifty-six healthy subjects (28 women and 28 men, age [mean ± standard deviation]: 21.6 ± 2.2 y) participated in this functional magnetic resonance imaging (fMRI) study. Methods and Results: Auditory cues were associated with pictures of faces during their encoding. These memory cues delivered during REM sleep enhanced subsequent accurate recollections but also false recognitions. These results suggest that reactivated memories interacted with semantically related representations, and induced new creative associations, which subsequently reduced the distinction between new and previously encoded exemplars. Cues had no effect if presented during stage 2 sleep, or if they were not associated with faces during encoding. Functional magnetic resonance imaging revealed that following exposure to conditioned cues during REM sleep, responses to faces during retrieval were enhanced both in a visual area and in a cortical region of multisensory (auditory-visual) convergence. Conclusions: These results show that reactivating memories during REM sleep enhances cortical responses during retrieval, suggesting the integration of recent memories within cortical circuits, favoring the generalization and schematization of the information. Citation: Sterpenich V, Schmidt C, Albouy G, Matarazzo L, Vanhaudenhuyse A, Boveroux P, Degueldre C, Leclercq Y, Balteau E, Collette F, Luxen A, Phillips C, Maquet P. Memory reactivation during rapid eye movement sleep promotes its generalization and integration in cortical stores. SLEEP 2014;37(6):1061-1075. PMID:24882901

  12. Chronic escitalopram treatment attenuated the accelerated rapid eye movement sleep transitions after selective rapid eye movement sleep deprivation: a model-based analysis using Markov chains.

    Science.gov (United States)

    Kostyalik, Diána; Vas, Szilvia; Kátai, Zita; Kitka, Tamás; Gyertyán, István; Bagdy, Gyorgy; Tóthfalusi, László

    2014-11-19

    Shortened rapid eye movement (REM) sleep latency and increased REM sleep amount are presumed biological markers of depression. These sleep alterations are also observable in several animal models of depression as well as during the rebound sleep after selective REM sleep deprivation (RD). Furthermore, REM sleep fragmentation is typically associated with stress procedures and anxiety. The selective serotonin reuptake inhibitor (SSRI) antidepressants reduce REM sleep time and increase REM latency after acute dosing in normal condition and even during REM rebound following RD. However, their therapeutic outcome evolves only after weeks of treatment, and the effects of chronic treatment in REM-deprived animals have not been studied yet. Chronic escitalopram- (10 mg/kg/day, osmotic minipump for 24 days) or vehicle-treated rats were subjected to a 3-day-long RD on day 21 using the flower pot procedure or kept in home cage. On day 24, fronto-parietal electroencephalogram, electromyogram and motility were recorded in the first 2 h of the passive phase. The observed sleep patterns were characterized applying standard sleep metrics, by modelling the transitions between sleep phases using Markov chains and by spectral analysis. Based on Markov chain analysis, chronic escitalopram treatment attenuated the REM sleep fragmentation [accelerated transition rates between REM and non-REM (NREM) stages, decreased REM sleep residence time between two transitions] during the rebound sleep. Additionally, the antidepressant avoided the frequent awakenings during the first 30 min of recovery period. The spectral analysis showed that the SSRI prevented the RD-caused elevation in theta (5-9 Hz) power during slow-wave sleep. Conversely, based on the aggregate sleep metrics, escitalopram had only moderate effects and it did not significantly attenuate the REM rebound after RD. In conclusion, chronic SSRI treatment is capable of reducing several effects on sleep which might be the consequence

  13. Morning rapid eye movement sleep naps facilitate broad access to emotional semantic networks.

    Science.gov (United States)

    Carr, Michelle; Nielsen, Tore

    2015-03-01

    The goal of the study was to assess semantic priming to emotion and nonemotion cue words using a novel measure of associational breadth for participants who either took rapid eye movement (REM) or nonrapid eye movement (NREM) naps or who remained awake; assess relation of priming to REM sleep consolidation and REM sleep inertia effects. The associational breadth task was applied in both a priming condition, where cue-words were signaled to be memorized prior to sleep (primed), and a nonpriming condition, where cue words were not memorized (nonprimed). Cue words were either emotional (positive, negative) or nonemotional. Participants were randomly assigned to either an awake (WAKE) or a sleep condition, which was subsequently split into NREM or REM groups depending on stage at awakening. Hospital-based sleep laboratory. Fifty-eight healthy participants (22 male) ages 18 to 35 y (Mage = 23.3 ± 4.08 y). The REM group scored higher than the NREM or WAKE groups on primed, but not nonprimed emotional cue words; the effect was stronger for positive than for negative cue words. However, REM time and percent correlated negatively with degree of emotional priming. Priming occurred for REM awakenings but not for NREM awakenings, even when the latter sleep episodes contained some REM sleep. Associational breadth may be selectively consolidated during REM sleep for stimuli that have been tagged as important for future memory retrieval. That priming decreased with REM time and was higher only for REM sleep awakenings is consistent with two explanatory REM sleep processes: REM sleep consolidation serving emotional downregulation and REM sleep inertia. © 2015 Associated Professional Sleep Societies, LLC.

  14. Application of a regularized model inversion system (REGFLEC) to multi-temporal RapidEye imagery for retrieving vegetation characteristics

    KAUST Repository

    Houborg, Rasmus; McCabe, Matthew

    2015-01-01

    to time-series of 5 m resolution multi-spectral RapidEye data is demonstrated over an irrigated agricultural region in central Saudi Arabia, showcasing the value of satellite-derived crop information at this fine scale for precision management. Validation

  15. Exploiting machine learning algorithms for tree species classification in a semiarid woodland using RapidEye image

    CSIR Research Space (South Africa)

    Adelabu, S

    2013-11-01

    Full Text Available in semiarid environments. In this study, we examined the suitability of 5-band RapidEye satellite data for the classification of five tree species in mopane woodland of Botswana using machine leaning algorithms with limited training samples. We performed...

  16. Using RapidEye and MODIS Data Fusion to Monitor Vegetation Dynamics in Semi-Arid Rangelands in South Africa

    Directory of Open Access Journals (Sweden)

    Andreas Tewes

    2015-05-01

    Full Text Available Image time series of high temporal and spatial resolution capture land surface dynamics of heterogeneous landscapes. We applied the ESTARFM (Enhanced Spatial and Temporal Adaptive Reflectance Fusion Model algorithm to multi-spectral images covering two semi-arid heterogeneous rangeland study sites located in South Africa. MODIS 250 m resolution and RapidEye 5 m resolution images were fused to produce synthetic RapidEye images, from June 2011 to July 2012. We evaluated the performance of the algorithm by comparing predicted surface reflectance values to real RapidEye images. Our results show that ESTARFM predictions are accurate, with a coefficient of determination for the red band 0.80 < R2 < 0.92, and for the near-infrared band 0.83 < R2 < 0.93, a mean relative bias between 6% and 12% for the red band and 4% to 9% in the near-infrared band. Heterogeneous vegetation at sub-MODIS resolution is captured adequately: A comparison of NDVI time series derived from RapidEye and ESTARFM data shows that the characteristic phenological dynamics of different vegetation types are reproduced well. We conclude that the ESTARFM algorithm allows us to produce synthetic remote sensing images at high spatial combined with high temporal resolution and so provides valuable information on vegetation dynamics in semi-arid, heterogeneous rangeland landscapes.

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

    Directory of Open Access Journals (Sweden)

    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.

  18. Impulse control disorder and rapid eye movement sleep behavior disorder in Parkinson's disease.

    Science.gov (United States)

    Bayard, Sophie; Dauvilliers, Yves; Yu, Huan; Croisier-Langenier, Muriel; Rossignol, Alexia; Charif, Mahmoud; Geny, Christian; Carlander, Bertrand; Cochen De Cock, Valérie

    2014-12-01

    The relationship between ICD and RBD is still not yet understood and the results from the current literature are contradictory in PD. We aimed to explore the association between rapid eye movement (REM) sleep behavior disorder (RBD) and impulse control disorder in Parkinson's disease. Ninety-eight non-demented patients with Parkinson's disease underwent one night of video-polysomnography recording. The diagnosis of RBD was established according to clinical and polysomnographic criteria. Impulse control disorders were determined by a gold standard, semi-structured diagnostic interview. Half of the patients (n = 49) reported clinical history of RBD while polysomnographic diagnosis of RBD was confirmed in 31.6% of the patients (n = 31). At least one impulse control disorder was identified in 21.4% of patients, 22.6% with RBD and 20.9% without. Logistic regression controlling for potential confounders indicated that both clinical RBD (OR = 0.34, 95% CI = 0.07-1.48, P = 0.15) and polysomnographic confirmed RBD diagnoses (OR = 0.1.28, 95% CI = 0.31-5.33, P = 0.34) were not associated with impulse control disorder. In Parkinson's disease, REM Sleep Behavior Disorder is not associated with impulse control disorder. The results of our study do not support the notion that PSG-confirmed RBD and ICD share a common pathophysiology. Copyright © 2014 Elsevier Ltd. All rights reserved.

  19. Neurophysiological basis of rapid eye movement sleep behavior disorder: informing future drug development

    Directory of Open Access Journals (Sweden)

    Jennum P

    2016-04-01

    Full Text Available Poul Jennum, Julie AE Christensen, Marielle Zoetmulder Department of Clinical Neurophysiology, Faculty of Health Sciences, Danish Center for Sleep Medicine, Rigshospitalet, University of Copenhagen, Copenhagen, Denmark Abstract: Rapid eye movement (REM sleep behavior disorder (RBD is a parasomnia characterized by a history of recurrent nocturnal dream enactment behavior and loss of skeletal muscle atonia and increased phasic muscle activity during REM sleep: REM sleep without atonia. RBD and associated comorbidities have recently been identified as one of the most specific and potentially sensitive risk factors for later development of any of the alpha-synucleinopathies: Parkinson’s disease, dementia with Lewy bodies, and other atypical parkinsonian syndromes. Several other sleep-related abnormalities have recently been identified in patients with RBD/Parkinson’s disease who experience abnormalities in sleep electroencephalographic frequencies, sleep–wake transitions, wake and sleep stability, occurrence and morphology of sleep spindles, and electrooculography measures. These findings suggest a gradual involvement of the brainstem and other structures, which is in line with the gradual involvement known in these disorders. We propose that these findings may help identify biomarkers of individuals at high risk of subsequent conversion to parkinsonism. Keywords: motor control, brain stem, hypothalamus, hypocretin

  20. Rapid eye movement sleep behavior disorder in treatment-naïve Parkinson disease patients.

    Science.gov (United States)

    Plomhause, Lucie; Dujardin, Kathy; Duhamel, Alain; Delliaux, Marie; Derambure, Philippe; Defebvre, Luc; Monaca Charley, Christelle

    2013-10-01

    Rapid eye movement (REM) sleep behavior disorder (RBD) is a risk factor for dementia in Parkinson disease (PD) patients. The objectives of our study were to prospectively evaluate the frequency of RBD in a sample of treatment-naïve, newly diagnosed PD patients and compare sleep characteristics and cognition in RBD and non-RBD groups. Fifty-seven newly diagnosed PD patients were consecutively recruited in a university medical center. All patients underwent two overnight polysomnography (PSG) sessions and were diagnosed with RBD according to the International Classification of Sleep Disorders, Second Revision criteria. Daytime sleepiness was measured in a multiple sleep latency test (MSLT). Cognition was assessed in a standard neuropsychologic examination. Seventeen PD patients (30%) met the criteria for RBD. The RBD patients and non-RBD patients did not significantly differ in mean age, gender ratio, disease duration, motor symptom subtype and severity, total sleep time, percentage of REM sleep, apnea-hypopnea index, mean oxygen saturation, and importantly cognitive performance. However, non-RBD patients had a significantly shorter mean daytime sleep latency than RBD patients (15 vs. 18 min, respectively; P=.014). A high frequency of RBD was found in our sample of 57 newly diagnosed PD patients. At this stage in the disease, RBD was not found to be associated with other sleep disorders or cognitive decline. Follow-up is needed to assess the risk for developing dementia in early-stage PD patients with RBD. Copyright © 2013 Elsevier B.V. All rights reserved.

  1. Neurophysiological basis of rapid eye movement sleep behavior disorder: informing future drug development

    Science.gov (United States)

    Jennum, Poul; Christensen, Julie AE; Zoetmulder, Marielle

    2016-01-01

    Rapid eye movement (REM) sleep behavior disorder (RBD) is a parasomnia characterized by a history of recurrent nocturnal dream enactment behavior and loss of skeletal muscle atonia and increased phasic muscle activity during REM sleep: REM sleep without atonia. RBD and associated comorbidities have recently been identified as one of the most specific and potentially sensitive risk factors for later development of any of the alpha-synucleinopathies: Parkinson’s disease, dementia with Lewy bodies, and other atypical parkinsonian syndromes. Several other sleep-related abnormalities have recently been identified in patients with RBD/Parkinson’s disease who experience abnormalities in sleep electroencephalographic frequencies, sleep–wake transitions, wake and sleep stability, occurrence and morphology of sleep spindles, and electrooculography measures. These findings suggest a gradual involvement of the brainstem and other structures, which is in line with the gradual involvement known in these disorders. We propose that these findings may help identify biomarkers of individuals at high risk of subsequent conversion to parkinsonism. PMID:27186147

  2. Radiometric and geometric assessment of data from the RapidEye constellation of satellites

    Science.gov (United States)

    Chander, Gyanesh; Haque, Md. Obaidul; Sampath, Aparajithan; Brunn, A.; Trosset, G.; Hoffmann, D.; Roloff, S.; Thiele, M.; Anderson, C.

    2013-01-01

    To monitor land surface processes over a wide range of temporal and spatial scales, it is critical to have coordinated observations of the Earth's surface using imagery acquired from multiple spaceborne imaging sensors. The RapidEye (RE) satellite constellation acquires high-resolution satellite images covering the entire globe within a very short period of time by sensors identical in construction and cross-calibrated to each other. To evaluate the RE high-resolution Multi-spectral Imager (MSI) sensor capabilities, a cross-comparison between the RE constellation of sensors was performed first using image statistics based on large common areas observed over pseudo-invariant calibration sites (PICS) by the sensors and, second, by comparing the on-orbit radiometric calibration temporal trending over a large number of calibration sites. For any spectral band, the individual responses measured by the five satellites of the RE constellation were found to differ B2B) alignment of the image data sets. The position accuracy was assessed by comparing the RE imagery against high-resolution aerial imagery, while the B2B characterization was performed by registering each band against every other band to ensure that the proper band alignment is provided for an image product. The B2B results indicate that the internal alignments of these five RE bands are in agreement, with bands typically registered to within 0.25 pixels of each other or better.

  3. The rostromedial tegmental nucleus is essential for non-rapid eye movement sleep.

    Directory of Open Access Journals (Sweden)

    Su-Rong Yang

    2018-04-01

    Full Text Available The rostromedial tegmental nucleus (RMTg, also called the GABAergic tail of the ventral tegmental area, projects to the midbrain dopaminergic system, dorsal raphe nucleus, locus coeruleus, and other regions. Whether the RMTg is involved in sleep-wake regulation is unknown. In the present study, pharmacogenetic activation of rat RMTg neurons promoted non-rapid eye movement (NREM sleep with increased slow-wave activity (SWA. Conversely, rats after neurotoxic lesions of 8 or 16 days showed decreased NREM sleep with reduced SWA at lights on. The reduced SWA persisted at least 25 days after lesions. Similarly, pharmacological and pharmacogenetic inactivation of rat RMTg neurons decreased NREM sleep. Electrophysiological experiments combined with optogenetics showed a direct inhibitory connection between the terminals of RMTg neurons and midbrain dopaminergic neurons. The bidirectional effects of the RMTg on the sleep-wake cycle were mimicked by the modulation of ventral tegmental area (VTA/substantia nigra compacta (SNc dopaminergic neuronal activity using a pharmacogenetic approach. Furthermore, during the 2-hour recovery period following 6-hour sleep deprivation, the amount of NREM sleep in both the lesion and control rats was significantly increased compared with baseline levels; however, only the control rats showed a significant increase in SWA compared with baseline levels. Collectively, our findings reveal an essential role of the RMTg in the promotion of NREM sleep and homeostatic regulation.

  4. Tumor Necrosis Factor Antagonism Normalizes Rapid Eye Movement Sleep in Alcohol Dependence

    Science.gov (United States)

    Irwin, Michael R.; Olmstead, Richard; Valladares, Edwin M.; Breen, Elizabeth Crabb; Ehlers, Cindy L.

    2009-01-01

    Background In alcohol dependence, markers of inflammation are associated with increases in rapid eye movement (REM) sleep, which is thought to be a prognostic indicator of alcohol relapse. This study was undertaken to test whether blockade of biologically active tumor necrosis factor-α (TNF-α) normalizes REM sleep in alcohol-dependent adults. Methods In a randomized, placebo-controlled, double-blind, crossover trial, 18 abstinent alcohol-dependent male adults received a single dose of etanercept (25 mg) versus placebo in a counterbalanced order. Polysomnographic sleep was measured at baseline and for 3 nights after the acute dose of etanercept or placebo. Results Compared with placebo, administration of etanercept produced significant decreases in the amount and percentage of REM sleep. Decreases in REM sleep were robust and approached low levels typically found in age-comparable control subjects. Individual differences in biologically active drug as indexed by circulating levels of soluble tumor necrosis factor receptor II negatively correlated with the percentage of REM sleep. Conclusions Pharmacologic neutralization of TNF-α activity is associated with significant reductions in REM sleep in abstinent alcohol-dependent patients. These data suggest that circulating levels of TNF-α may have a physiologic role in the regulation of REM sleep in humans. PMID:19185287

  5. Do patients with rapid eye movement sleep behavior disorder have a disease-specific personality?

    Science.gov (United States)

    Sasai, Taeko; Inoue, Yuichi; Matsuura, Masato

    2012-06-01

    Rapid eye movement sleep behavior disorder (RBD) occurs idiopathically (iRBD), frequently representing a prodromal phase of Parkinson's disease (PD). Previous reports have described that patients with PD have premorbid personality profiles such as industriousness, inflexibility, cautiousness, and lack of novelty seeking. As well, psychological stress often aggravates RBD symptoms. These phenomena encouraged us to investigate personality profiles in iRBD patients. In this study, 53 patients with iRBD and 49 age and sex-matched healthy controls (HC) were enrolled. We used the revised version of the NEO Personality Inventory (NEO-PIR) to measure the personality of these subjects, and the 5 domains and the 30 facets of the NEO-PIR were compared between the two groups. Within the iRBD group, we investigated the association between RBD variables, e.g. the proportion of REM sleep without atonia (RWA/REM), length of RBD morbidity, frequency of vocalization or abnormal behavior, and the variables of NEO-PIR. In the patients, olfactory function was significantly lower than that of healthy controls, but the inventory differences were not significant. The inventory showed no association with any RBD variable, or the existence of aggravation of these symptoms triggered by psychological stress, or olfactory dysfunction. These results suggest that RBD patients do not have a personality profile that might predict PD development. The personality profile itself cannot explain the psychological-stress-dependent aggravation of RBD symptoms. Copyright © 2011 Elsevier Ltd. All rights reserved.

  6. Rapid eye movement sleep behaviour disorder and striatal dopamine depletion in patients with Parkinson's disease.

    Science.gov (United States)

    Chung, S J; Lee, Y; Lee, J J; Lee, P H; Sohn, Y H

    2017-10-01

    Rapid eye movement sleep behaviour disorder (RBD) is related to striatal dopamine depletion. This study was performed to confirm whether clinically probable RBD (cpRBD) in patients with Parkinson's disease (PD) is associated with a specific pattern of striatal dopamine depletion. A prospective survey was conducted using the RBD Screening Questionnaire (RBDSQ) in 122 patients with PD who had undergone dopamine transporter (DAT) positron emission tomography scan. Patients with cpRBD (RBDSQ ≥ 7) exhibited greater motor deficits, predominantly in the less-affected side and axial symptoms, and were prescribed higher levodopa-equivalent doses at follow-up than those without cpRBD (RBDSQ ≤ 4), despite their similar disease and treatment durations. Compared to patients without cpRBD, those with cpRBD showed lower DAT activities in the putamen, particularly in the less-affected side in all putaminal subregions, and a tendency to be lower in the ventral striatum. In addition, greater motor deficits in patients with cpRBD than in those without cpRBD remained significant after controlling for DAT binding in the putamen and other confounding variables. These results demonstrated that the presence of RBD in patients with PD is associated with different patterns of both motor deficit distribution and striatal DAT depletion, suggesting that the presence of RBD represents a distinct PD subtype with a malignant motor parkinsonism. © 2017 EAN.

  7. Sleep alterations in mammals: did aquatic conditions inhibit rapid eye movement sleep?

    Science.gov (United States)

    Madan, Vibha; Jha, Sushil K

    2012-12-01

    Sleep has been studied widely in mammals and to some extent in other vertebrates. Higher vertebrates such as birds and mammals have evolved an inimitable rapid eye movement (REM) sleep state. During REM sleep, postural muscles become atonic and the temperature regulating machinery remains suspended. Although REM sleep is present in almost all the terrestrial mammals, the aquatic mammals have either radically reduced or completely eliminated REM sleep. Further, we found a significant negative correlation between REM sleep and the adaptation of the organism to live on land or in water. The amount of REM sleep is highest in terrestrial mammals, significantly reduced in semi-aquatic mammals and completely absent or negligible in aquatic mammals. The aquatic mammals are obligate swimmers and have to surface at regular intervals for air. Also, these animals live in thermally challenging environments, where the conductive heat loss is approximately ~90 times greater than air. Therefore, they have to be moving most of the time. As an adaptation, they have evolved unihemispheric sleep, during which they can rove as well as rest. A condition that immobilizes muscle activity and suspends the thermoregulatory machinery, as happens during REM sleep, is not suitable for these animals. It is possible that, in accord with Darwin's theory, aquatic mammals might have abolished REM sleep with time. In this review, we discuss the possibility of the intrinsic role of aquatic conditions in the elimination of REM sleep in the aquatic mammals.

  8. Normal Morning Melanin-Concentrating Hormone Levels and No Association with Rapid Eye Movement or Non-Rapid Eye Movement Sleep Parameters in Narcolepsy Type 1 and Type 2

    DEFF Research Database (Denmark)

    Schrölkamp, Maren; Jennum, Poul J; Gammeltoft, Steen

    2017-01-01

    in rapid eye movement (REM) and non-rapid eye movement (NREM) sleep regulation. Hypocretin neurons reciprocally interact with MCH neurons. We hypothesized that altered MCH secretion contributes to the symptoms and sleep abnormalities of narcolepsy and that this is reflected in morning cerebrospinal fluid...... MCH levels. CONCLUSIONS: Our study shows that MCH levels in CSF collected in the morning are normal in narcolepsy and not associated with the clinical symptoms, REM sleep abnormalities, nor number of muscle movements during REM or NREM sleep of the patients. We conclude that morning lumbar CSF MCH......STUDY OBJECTIVES: Other than hypocretin-1 (HCRT-1) deficiency in narcolepsy type 1 (NT1), the neurochemical imbalance of NT1 and narcolepsy type 2 (NT2) with normal HCRT-1 levels is largely unknown. The neuropeptide melanin-concentrating hormone (MCH) is mainly secreted during sleep and is involved...

  9. Validation of an integrated software for the detection of rapid eye movement sleep behavior disorder.

    Science.gov (United States)

    Frauscher, Birgit; Gabelia, David; Biermayr, Marlene; Stefani, Ambra; Hackner, Heinz; Mitterling, Thomas; Poewe, Werner; Högl, Birgit

    2014-10-01

    Rapid eye movement sleep without atonia (RWA) is the polysomnographic hallmark of REM sleep behavior disorder (RBD). To partially overcome the disadvantages of manual RWA scoring, which is time consuming but essential for the accurate diagnosis of RBD, we aimed to validate software specifically developed and integrated with polysomnography for RWA detection against the gold standard of manual RWA quantification. Academic referral center sleep laboratory. Polysomnographic recordings of 20 patients with RBD and 60 healthy volunteers were analyzed. N/A. Motor activity during REM sleep was quantified manually and computer assisted (with and without artifact detection) according to Sleep Innsbruck Barcelona (SINBAR) criteria for the mentalis ("any," phasic, tonic electromyographic [EMG] activity) and the flexor digitorum superficialis (FDS) muscle (phasic EMG activity). Computer-derived indices (with and without artifact correction) for "any," phasic, tonic mentalis EMG activity, phasic FDS EMG activity, and the SINBAR index ("any" mentalis + phasic FDS) correlated well with the manually derived indices (all Spearman rhos 0.66-0.98). In contrast with computerized scoring alone, computerized scoring plus manual artifact correction (median duration 5.4 min) led to a significant reduction of false positives for "any" mentalis (40%), phasic mentalis (40.6%), and the SINBAR index (41.2%). Quantification of tonic mentalis and phasic FDS EMG activity was not influenced by artifact correction. The computer algorithm used here appears to be a promising tool for REM sleep behavior disorder detection in both research and clinical routine. A short check for plausibility of automatic detection should be a basic prerequisite for this and all other available computer algorithms. © 2014 Associated Professional Sleep Societies, LLC.

  10. Phenomapping of rangelands in South Africa using time series of RapidEye data

    Science.gov (United States)

    Parplies, André; Dubovyk, Olena; Tewes, Andreas; Mund, Jan-Peter; Schellberg, Jürgen

    2016-12-01

    Phenomapping is an approach which allows the derivation of spatial patterns of vegetation phenology and rangeland productivity based on time series of vegetation indices. In our study, we propose a new spatial mapping approach which combines phenometrics derived from high resolution (HR) satellite time series with spatial logistic regression modeling to discriminate land management systems in rangelands. From the RapidEye time series for selected rangelands in South Africa, we calculated bi-weekly noise reduced Normalized Difference Vegetation Index (NDVI) images. For the growing season of 2011⿿2012, we further derived principal phenology metrics such as start, end and length of growing season and related phenological variables such as amplitude, left derivative and small integral of the NDVI curve. We then mapped these phenometrics across two different tenure systems, communal and commercial, at the very detailed spatial resolution of 5 m. The result of a binary logistic regression (BLR) has shown that the amplitude and the left derivative of the NDVI curve were statistically significant. These indicators are useful to discriminate commercial from communal rangeland systems. We conclude that phenomapping combined with spatial modeling is a powerful tool that allows efficient aggregation of phenology and productivity metrics for spatially explicit analysis of the relationships of crop phenology with site conditions and management. This approach has particular potential for disaggregated and patchy environments such as in farming systems in semi-arid South Africa, where phenology varies considerably among and within years. Further, we see a strong perspective for phenomapping to support spatially explicit modelling of vegetation.

  11. Apnea-induced rapid eye movement sleep disruption impairs human spatial navigational memory.

    Science.gov (United States)

    Varga, Andrew W; Kishi, Akifumi; Mantua, Janna; Lim, Jason; Koushyk, Viachaslau; Leibert, David P; Osorio, Ricardo S; Rapoport, David M; Ayappa, Indu

    2014-10-29

    Hippocampal electrophysiology and behavioral evidence support a role for sleep in spatial navigational memory, but the role of particular sleep stages is less clear. Although rodent models suggest the importance of rapid eye movement (REM) sleep in spatial navigational memory, a similar role for REM sleep has never been examined in humans. We recruited subjects with severe obstructive sleep apnea (OSA) who were well treated and adherent with continuous positive airway pressure (CPAP). Restricting CPAP withdrawal to REM through real-time monitoring of the polysomnogram provides a novel way of addressing the role of REM sleep in spatial navigational memory with a physiologically relevant stimulus. Individuals spent two different nights in the laboratory, during which subjects performed timed trials before and after sleep on one of two unique 3D spatial mazes. One night of sleep was normally consolidated with use of therapeutic CPAP throughout, whereas on the other night, CPAP was reduced only in REM sleep, allowing REM OSA to recur. REM disruption via this method caused REM sleep reduction and significantly fragmented any remaining REM sleep without affecting total sleep time, sleep efficiency, or slow-wave sleep. We observed improvements in maze performance after a night of normal sleep that were significantly attenuated after a night of REM disruption without changes in psychomotor vigilance. Furthermore, the improvement in maze completion time significantly positively correlated with the mean REM run duration across both sleep conditions. In conclusion, we demonstrate a novel role for REM sleep in human memory formation and highlight a significant cognitive consequence of OSA. Copyright © 2014 the authors 0270-6474/14/3414571-07$15.00/0.

  12. Rapid-Eye-Movement-Sleep (REM Associated Enhancement of Working Memory Performance after a Daytime Nap.

    Directory of Open Access Journals (Sweden)

    Esther Yuet Ying Lau

    Full Text Available The main objective was to study the impact of a daytime sleep opportunity on working memory and the mechanism behind such impact. This study adopted an experimental design in a sleep research laboratory. Eighty healthy college students (Age:17-23, 36 males were randomized to either have a polysomnography-monitored daytime sleep opportunity (Nap-group, n=40 or stay awake (Wake-group, n=40 between the two assessment sessions. All participants completed a sleep diary and wore an actigraph-watch for 5 days before and one day after the assessment sessions. They completed the state-measurement of sleepiness and affect, in addition to a psychomotor vigilance test and a working memory task before and after the nap/wake sessions. The two groups did not differ in their sleep characteristics prior to and after the lab visit. The Nap-group had higher accuracy on the working memory task, fewer lapses on the psychomotor vigilance test and lower state-sleepiness than the Wake-group. Within the Nap-group, working memory accuracy was positively correlated with duration of rapid eye movement sleep (REM and total sleep time during the nap. Our findings suggested that "sleep gain" during a daytime sleep opportunity had significant positive impact on working memory performance, without affecting subsequent nighttime sleep in young adult, and such impact was associated with the duration of REM. While REM abnormality has long been noted in pathological conditions (e.g. depression, which are also presented with cognitive dysfunctions (e.g. working memory deficits, this was the first evidence showing working memory enhancement associated with REM in daytime napping in college students, who likely had habitual short sleep duration but were otherwise generally healthy.

  13. Clinical features of Parkinson's disease with and without rapid eye movement sleep behavior disorder.

    Science.gov (United States)

    Liu, Ye; Zhu, Xiao-Ying; Zhang, Xiao-Jin; Kuo, Sheng-Han; Ondo, William G; Wu, Yun-Cheng

    2017-01-01

    Rapid eye movement sleep behavior disorder (RBD) and Parkinson's disease (PD) are two distinct clinical diseases but they share some common pathological and anatomical characteristics. This study aims to confirm the clinical features of RBD in Chinese PD patients. One hundred fifty PD patients were enrolled from the Parkinson`s disease and Movement Disorders Center in  Department of Neurology, Shanghai General Hospital from January 2013 to August 2014. This study examined PD patients with or without RBD as determined by the REM Sleep Behavior Disorder Screening Questionnaire (RBDSQ), assessed motor subtype by Unified PD Rating Scale (UPDRS) III at "on" state, and compared the sub-scale scores representing tremor, rigidity, appendicular and axial. Investigators also assessed the Hamilton Anxiety Scale (HAMA), Hamilton Depression Scale (HAMD), Mini-Mental State Examination (MMSE), Clinical Dementia Rating (CDR), and Parkinson's disease Sleep Scale (PDSS). One hundred fourty one PD patients entered the final study. 30 (21.28%) PD patients had probable RBD (pRBD) diagnosed with a RBDSQ score of 6 or above. There were no significant differences for age, including age of PD onset and PD duration, gender, smoking status, alcohol or coffee use, presence of anosmia or freezing, UPDRS III, and H-Y stages between the pRBD + and pRBD - groups. pRBD + group had lower MMSE scores, higher PDSS scores, and pRBD + PD patients had more prominent proportion in anxiety, depression, constipation, hallucination and a greater prevalence of orthostatic hypotension. pRBD + PD patients exhibited greater changes in non-motor symptoms. However, there was no increase in motor deficits.

  14. Quantitative assessment of motor speech abnormalities in idiopathic rapid eye movement sleep behaviour disorder.

    Science.gov (United States)

    Rusz, Jan; Hlavnička, Jan; Tykalová, Tereza; Bušková, Jitka; Ulmanová, Olga; Růžička, Evžen; Šonka, Karel

    2016-03-01

    Patients with idiopathic rapid eye movement sleep behaviour disorder (RBD) are at substantial risk for developing Parkinson's disease (PD) or related neurodegenerative disorders. Speech is an important indicator of motor function and movement coordination, and therefore may be an extremely sensitive early marker of changes due to prodromal neurodegeneration. Speech data were acquired from 16 RBD subjects and 16 age- and sex-matched healthy control subjects. Objective acoustic assessment of 15 speech dimensions representing various phonatory, articulatory, and prosodic deviations was performed. Statistical models were applied to characterise speech disorders in RBD and to estimate sensitivity and specificity in differentiating between RBD and control subjects. Some form of speech impairment was revealed in 88% of RBD subjects. Articulatory deficits were the most prominent findings in RBD. In comparison to controls, the RBD group showed significant alterations in irregular alternating motion rates (p = 0.009) and articulatory decay (p = 0.01). The combination of four distinctive speech dimensions, including aperiodicity, irregular alternating motion rates, articulatory decay, and dysfluency, led to 96% sensitivity and 79% specificity in discriminating between RBD and control subjects. Speech impairment was significantly more pronounced in RBD subjects with the motor score of the Unified Parkinson's Disease Rating Scale greater than 4 points when compared to other RBD individuals. Simple quantitative speech motor measures may be suitable for the reliable detection of prodromal neurodegeneration in subjects with RBD, and therefore may provide important outcomes for future therapy trials. Copyright © 2015 Elsevier B.V. All rights reserved.

  15. Rapid-Eye-Movement-Sleep (REM) Associated Enhancement of Working Memory Performance after a Daytime Nap

    Science.gov (United States)

    Lau, Kristy Nga Ting; Hui, Florence Wai Ying; Tseng, Chia-huei

    2015-01-01

    The main objective was to study the impact of a daytime sleep opportunity on working memory and the mechanism behind such impact. This study adopted an experimental design in a sleep research laboratory. Eighty healthy college students (Age:17-23, 36 males) were randomized to either have a polysomnography-monitored daytime sleep opportunity (Nap-group, n=40) or stay awake (Wake-group, n=40) between the two assessment sessions. All participants completed a sleep diary and wore an actigraph-watch for 5 days before and one day after the assessment sessions. They completed the state-measurement of sleepiness and affect, in addition to a psychomotor vigilance test and a working memory task before and after the nap/wake sessions. The two groups did not differ in their sleep characteristics prior to and after the lab visit. The Nap-group had higher accuracy on the working memory task, fewer lapses on the psychomotor vigilance test and lower state-sleepiness than the Wake-group. Within the Nap-group, working memory accuracy was positively correlated with duration of rapid eye movement sleep (REM) and total sleep time during the nap. Our findings suggested that “sleep gain” during a daytime sleep opportunity had significant positive impact on working memory performance, without affecting subsequent nighttime sleep in young adult, and such impact was associated with the duration of REM. While REM abnormality has long been noted in pathological conditions (e.g. depression), which are also presented with cognitive dysfunctions (e.g. working memory deficits), this was the first evidence showing working memory enhancement associated with REM in daytime napping in college students, who likely had habitual short sleep duration but were otherwise generally healthy. PMID:25970511

  16. [Syndrome of rapid eye movement sleep behavior disorder and nocturia in Parkinson's disease].

    Science.gov (United States)

    Nodel, M R; Ukraintseva, Yu V; Yakhno, N N

    Parasomnia, a syndrome of rapid eye movement sleep behavior disorder (RBD), is a common non-motor impairment in patients with Parkinson's disease (PD). The relationship between RBD with other symptoms of PD affecting night sleep, in particular, nocturia, is understudied. An aim of the study was to determine the symptoms related to night sleep disturbances in PD patients with RBD and assess the dynamics of these disturbances with the disease progression taking into account RBD onset. One hundred and forty patients (72 male and 68 female) with PD without dementia (mean age 61.98±0.79 years, PD stage - 2.35±0.05, duration 5.82±90.65 years) were examined. Motor disorders were assessed with the unified Parkinson's disease rating scale (UPDRS), sleep disturbances and frequent night urinations were evaluated with the Parkinson's Disease Sleep Scale (PDSS). The diagnosis of probable RBD was based on reports of patients or their relatives on the dream-related motor activity and vocalization. Quality-of-life was evaluated with the Parkinson's Disease Questionnaire (PDQ-39). Patients were followed up after 2.5 years. Probable RBD was diagnosed in 46.43% of patients, including 30.77%, who developed the syndrome before the manifestation of motor symptoms, 16.92% patients with simultaneous development of RBD and motor symptoms and 52.31% with RBD development >2 years after motor disorders. Patients with RBD differed from those without parasomnia by the higher severity of nocturia. After 2.5 years of follow-up, the severity of disease was greater in patients with RBD assessed by UPDRS, quality-of-life indices, severity of nocturia and episodes of nocturia. The highest frequency of episodes of nocturia was noted in patients with early onset of RBD before the manifestation of motor symptoms. RBD in patients with PD is associated with the rapid progress of nocturia, higher degree of worsening of daily activities and deterioration of quality of life. The relationship between RBD

  17. Non-Rapid Eye Movement Sleep Parasomnias and Migraine: A Role of Orexinergic Projections

    Directory of Open Access Journals (Sweden)

    Antonietta Messina

    2018-02-01

    Full Text Available IntroductionSleep and migraine share a common pathophysiological substrate, although the underlying mechanisms are unknown. The serotonergic and orexinergic systems are both involved in the regulation of sleep/wake cycle, and numerous studies show that both are involved in the migraine etiopathogenesis. These two systems are anatomically and functionally interconnected. Our hypothesis is that in migraine a dysfunction of orexinergic projections on the median raphe (MR nuclei, interfering with serotonergic regulation, may cause Non-Rapid Eye Movement parasomnias, such as somnambulism.Hypothesis/theoryActing on the serotonergic neurons of the raphe nuclei, the dysfunction of orexinergic neurons would lead to a higher release of serotonin. The activation of serotonergic receptors located on the walls of large cerebral vessels would lead to abnormal vasodilatation and consequently increase transmural pressure. This process could activate the trigeminal nerve terminals that innervate vascular walls. As a consequence, there is activation of sensory nerve endings at the level of hard vessels in the meninges, with release of pro-inflammatory peptides (e.g., substance P and CGRP. Within this hypothetical frame, the released serotonin could also interact with trigeminovascular afferents to activate and/or facilitate the release of the neuropeptide at the level of the trigeminal ganglion. The dysregulation of the physiological negative feedback of serotonin on the orexinergic neurons, in turn, would contribute to an alteration of the whole system, altering the sleep–wake cycle.ConclusionSerotonergic neurons of the MR nuclei receive an excitatory input from hypothalamic orexin/hypocretin neurons and reciprocally inhibit orexin/hypocretin neurons through the serotonin 1A receptor (or 5-HT1A receptor. Considering this complex system, if there is an alteration it may facilitate the pathophysiological mechanisms involved in the migraine, while it may produce

  18. Rapid eye movement sleep deprivation induces an increase in acetylcholinesterase activity in discrete rat brain regions

    Directory of Open Access Journals (Sweden)

    Benedito M.A.C.

    2001-01-01

    Full Text Available Some upper brainstem cholinergic neurons (pedunculopontine and laterodorsal tegmental nuclei are involved in the generation of rapid eye movement (REM sleep and project rostrally to the thalamus and caudally to the medulla oblongata. A previous report showed that 96 h of REM sleep deprivation in rats induced an increase in the activity of brainstem acetylcholinesterase (Achase, the enzyme which inactivates acetylcholine (Ach in the synaptic cleft. There was no change in the enzyme's activity in the whole brain and cerebrum. The components of the cholinergic synaptic endings (for example, Achase are not uniformly distributed throughout the discrete regions of the brain. In order to detect possible regional changes we measured Achase activity in several discrete rat brain regions (medulla oblongata, pons, thalamus, striatum, hippocampus and cerebral cortex after 96 h of REM sleep deprivation. Naive adult male Wistar rats were deprived of REM sleep using the flower-pot technique, while control rats were left in their home cages. Total, membrane-bound and soluble Achase activities (nmol of thiocholine formed min-1 mg protein-1 were assayed photometrically. The results (mean ± SD obtained showed a statistically significant (Student t-test increase in total Achase activity in the pons (control: 147.8 ± 12.8, REM sleep-deprived: 169.3 ± 17.4, N = 6 for both groups, P<0.025 and thalamus (control: 167.4 ± 29.0, REM sleep-deprived: 191.9 ± 15.4, N = 6 for both groups, P<0.05. Increases in membrane-bound Achase activity in the pons (control: 171.0 ± 14.7, REM sleep-deprived: 189.5 ± 19.5, N = 6 for both groups, P<0.05 and soluble enzyme activity in the medulla oblongata (control: 147.6 ± 16.3, REM sleep-deprived: 163.8 ± 8.3, N = 6 for both groups, P<0.05 were also observed. There were no statistically significant differences in the enzyme's activity in the other brain regions assayed. The present findings show that the increase in Achase activity

  19. STOP-Bang Questionnaire in Patients with Rapid Eye Movement Sleep Behavior Disorder

    Directory of Open Access Journals (Sweden)

    Ki-Hwan Ji

    2017-12-01

    Full Text Available Background and Objective The snoring, tiredness, observed apnea, and high blood pressure– body mass index, age, neck circumference, and gender (STOP-Bang questionnaire is known as a simple but useful tool for the diagnosis of high-risk obstructive sleep apnea (OSA. However, the utility of STOP-Bang questionnaire in rapid eye movement (REM sleep behavior disorder (RBD populations is not validated. This study aimed to determine the diagnostic value of the STOP-Bang questionnaire in patients with RBD at high risk for OSA. Methods We collected data from 65 consecutive patients who were diagnosed with RBD in a tertiary sleep center (20 women; mean age, 64.3 ± 12.5 years. All the patients visited sleep center with complaints of abnormal behavior during sleep, and underwent testing with STOP-Bang questionnaire and polysomnography. The diagnosis of RBD was based on the International Classification of Sleep Disorders, second edition. We diagnosed OSA when apnea-hypopnea index (AHI was at least 5/h. The receiver operating characteristic (ROC curves were plotted. Results The mean AHI was 18.2 ± 16.5/h, and 75.4% (n = 49 had an AHI ≥ 5. The STOP-Bang (threshold ≥ 3 identified 70.7% of patients as high risk for OSA, and sensitivity, specificity, positive and negative predictive values were 81.6, 62.5, 87, and 52.6%, respectively. The area under the ROC curve (AUC was 0.79 (p < 0.001. The STOP (threshold ≥ 2 identified 70.7% of patients at high risk for OSA, and sensitivity, specificity, positive and negative predictive values were 75.5, 87.5, 94.9, and 53.8%, respectively. The AUC was 0.86 (p < 0.001. A pairwise comparison of ROC curve between STOP-Bang and STOP was insignificant (p = 0.145. Conclusions In RBD population, the STOP-Bang or STOP questionnaire is a useful screening tool to identify patients at high risk for OSA.

  20. The Use of Surveillance Cameras for the Rapid Mapping of Lava Flows: An Application to Mount Etna Volcano

    Directory of Open Access Journals (Sweden)

    Mauro Coltelli

    2017-02-01

    Full Text Available In order to improve the observation capability in one of the most active volcanic areas in the world, Mt. Etna, we developed a processing method to use the surveillance cameras for a quasi real-time mapping of syn-eruptive processes. Following an evaluation of the current performance of the Etna permanent ground NEtwork of Thermal and Visible Sensors (Etna_NETVIS, its possible implementation and optimization was investigated to determine the locations of additional observation sites to be rapidly set up during emergencies. A tool was then devised to process time series of ground-acquired images and extract a coherent multi-temporal dataset of georeferenced map. The processed datasets can be used to extract 2D features such as evolution maps of active lava flows. The tool was validated on ad-hoc test fields and then adopted to map the evolution of two recent lava flows. The achievable accuracy (about three times the original pixel size and the short processing time makes the tool suitable for rapidly assessing lava flow evolutions, especially in the case of recurrent eruptions, such as those of the 2011–2015 Etna activity. The tool can be used both in standard monitoring activities and during emergency phases (eventually improving the present network with additional mobile stations when it is mandatory to carry out a quasi-real-time mapping to support civil protection actions. The developed tool could be integrated in the control room of the Osservatorio Etneo, thus enabling the Etna_NETVIS for mapping purposes and not only for video surveillance.

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

    Science.gov (United States)

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

    2013-07-01

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

  2. Fragmentation of Rapid Eye Movement and Nonrapid Eye Movement Sleep without Total Sleep Loss Impairs Hippocampus-Dependent Fear Memory Consolidation.

    Science.gov (United States)

    Lee, Michael L; Katsuyama, Ângela M; Duge, Leanne S; Sriram, Chaitra; Krushelnytskyy, Mykhaylo; Kim, Jeansok J; de la Iglesia, Horacio O

    2016-11-01

    Sleep is important for consolidation of hippocampus-dependent memories. It is hypothesized that the temporal sequence of nonrapid eye movement (NREM) sleep and rapid eye movement (REM) sleep is critical for the weakening of nonadaptive memories and the subsequent transfer of memories temporarily stored in the hippocampus to more permanent memories in the neocortex. A great body of evidence supporting this hypothesis relies on behavioral, pharmacological, neural, and/or genetic manipulations that induce sleep deprivation or stage-specific sleep deprivation. We exploit an experimental model of circadian desynchrony in which intact animals are not deprived of any sleep stage but show fragmentation of REM and NREM sleep within nonfragmented sleep bouts. We test the hypothesis that the shortening of NREM and REM sleep durations post-training will impair memory consolidation irrespective of total sleep duration. When circadian-desynchronized animals are trained in a hippocampus-dependent contextual fear-conditioning task they show normal short-term memory but impaired long-term memory consolidation. This impairment in memory consolidation is positively associated with the post-training fragmentation of REM and NREM sleep but is not significantly associated with the fragmentation of total sleep or the total amount of delta activity. We also show that the sleep stage fragmentation resulting from circadian desynchrony has no effect on hippocampus-dependent spatial memory and no effect on hippocampus-independent cued fear-conditioning memory. Our findings in an intact animal model, in which sleep deprivation is not a confounding factor, support the hypothesis that the stereotypic sequence and duration of sleep stages play a specific role in long-term hippocampus-dependent fear memory consolidation. © 2016 Associated Professional Sleep Societies, LLC.

  3. Dopamine agonist suppression of rapid-eye-movement sleep is secondary to sleep suppression mediated via limbic structures

    International Nuclear Information System (INIS)

    Miletich, R.S.

    1985-01-01

    The effects of pergolide, a direct dopamine receptor agonist, on sleep and wakefulness, motor behavior and 3 H-spiperone specific binding in limbic structures and striatum in rats was studied. The results show that pergolide induced a biphasic dose effect, with high doses increasing wakefulness and suppressing sleep while low dose decreased wakefulness, but increased sleep. It was shown that pergolide-induced sleep suppression was blocked by α-glupenthixol and pimozide, two dopamine receptor antagonists. It was further shown that pergolide merely delayed the rebound resulting from rapid-eye-movement (REM) sleep deprivation, that dopamine receptors stimulation had no direct effect on the period, phase or amplitude of the circadian rhythm of REM sleep propensity and that there was no alteration in the coupling of REM sleep episodes with S 2 episodes. Rapid-eye-movement sleep deprivation resulted in increased sensitivity to the pergolide-induced wakefulness stimulation and sleep suppression and pergolide-induced motor behaviors of locomotion and head bobbing. 3 H-spiperone specific binding to dopamine receptors was shown to be altered by REM sleep deprivation in the subcortical limbic structures. It is concluded that the REM sleep suppressing action of dopamine receptor stimulation is secondary to sleep suppression per se and not secondary to a unique effect on the REM sleep. Further, it is suggested that the wakefulness stimulating action of dopamine receptor agonists is mediated by activation of the dopamine receptors in the terminal areas of the mesolimbocortical dopamine projection system

  4. Shorter duration of non-rapid eye movement sleep slow waves in EphA4 knockout mice.

    Science.gov (United States)

    Freyburger, Marlène; Poirier, Gaétan; Carrier, Julie; Mongrain, Valérie

    2017-10-01

    Slow waves occurring during non-rapid eye movement sleep have been associated with neurobehavioural performance and memory. In addition, the duration of previous wakefulness and sleep impacts characteristics of these slow waves. However, molecular mechanisms regulating the dynamics of slow-wave characteristics remain poorly understood. The EphA4 receptor regulates glutamatergic transmission and synaptic plasticity, which have both been linked to sleep slow waves. To investigate if EphA4 regulates slow-wave characteristics during non-rapid eye movement sleep, we compared individual parameters of slow waves between EphA4 knockout mice and wild-type littermates under baseline conditions and after a 6-h sleep deprivation. We observed that, compared with wild-type mice, knockout mice display a shorter duration of positive and negative phases of slow waves under baseline conditions and after sleep deprivation. However, the mutation did not change slow-wave density, amplitude and slope, and did not affect the sleep deprivation-dependent changes in slow-wave characteristics, suggesting that EphA4 is not involved in the response to elevated sleep pressure. Our present findings suggest a role for EphA4 in shaping cortical oscillations during sleep that is independent from sleep need. © 2017 European Sleep Research Society.

  5. Fight or flight? Dream content during sleepwalking/sleep terrors vs. rapid eye movement sleep behavior disorder.

    Science.gov (United States)

    Uguccioni, Ginevra; Golmard, Jean-Louis; de Fontréaux, Alix Noël; Leu-Semenescu, Smaranda; Brion, Agnès; Arnulf, Isabelle

    2013-05-01

    Dreams enacted during sleepwalking or sleep terrors (SW/ST) may differ from those enacted during rapid eye movement sleep behavior disorder (RBD). Subjects completed aggression, depression, and anxiety questionnaires. The mentations associated with SW/ST and RBD behaviors were collected over their lifetime and on the morning after video polysomnography (PSG). The reports were analyzed for complexity, length, content, setting, bizarreness, and threat. Ninety-one percent of 32 subjects with SW/ST and 87.5% of 24 subjects with RBD remembered an enacted dream (121 dreams in a lifetime and 41 dreams recalled on the morning). These dreams were more complex and less bizarre, with a higher level of aggression in the RBD than in SW/ST subjects. In contrast, we found low aggression, anxiety, and depression scores during the daytime in both groups. As many as 70% of enacted dreams in SW/ST and 60% in RBD involved a threat, but there were more misfortunes and disasters in the SW/ST dreams and more human and animal aggressions in the RBD dreams. The response to these threats differed, as the sleepwalkers mostly fled from a disaster (and 25% fought back when attacked), while 75% of RBD subjects counterattacked when assaulted. The dreams setting included their bedrooms in 42% SW/ST dreams, though this finding was exceptional in the RBD dreams. Different threat simulations and modes of defense seem to play a role during dream-enacted behaviors (e.g., fleeing a disaster during SW/ST, counterattacking a human or animal assault during RBD), paralleling and exacerbating the differences observed between normal dreaming in nonrapid eye movement (NREM) vs rapid eye movement (REM) sleep. Copyright © 2013 Elsevier B.V. All rights reserved.

  6. Chess players' eye movements reveal rapid recognition of complex visual patterns: Evidence from a chess-related visual search task.

    Science.gov (United States)

    Sheridan, Heather; Reingold, Eyal M

    2017-03-01

    To explore the perceptual component of chess expertise, we monitored the eye movements of expert and novice chess players during a chess-related visual search task that tested anecdotal reports that a key differentiator of chess skill is the ability to visualize the complex moves of the knight piece. Specifically, chess players viewed an array of four minimized chessboards, and they rapidly searched for the target board that allowed a knight piece to reach a target square in three moves. On each trial, there was only one target board (i.e., the "Yes" board), and for the remaining "lure" boards, the knight's path was blocked on either the first move (the "Easy No" board) or the second move (i.e., "the Difficult No" board). As evidence that chess experts can rapidly differentiate complex chess-related visual patterns, the experts (but not the novices) showed longer first-fixation durations on the "Yes" board relative to the "Difficult No" board. Moreover, as hypothesized, the task strongly differentiated chess skill: Reaction times were more than four times faster for the experts relative to novices, and reaction times were correlated with within-group measures of expertise (i.e., official chess ratings, number of hours of practice). These results indicate that a key component of chess expertise is the ability to rapidly recognize complex visual patterns.

  7. Cerebral O2 metabolism and cerebral blood flow in humans during deep and rapid-eye-movement sleep

    DEFF Research Database (Denmark)

    Madsen, P L; Schmidt, J F; Wildschiødtz, Gordon

    1991-01-01

    on examination of this question. We have now measured CBF and CMRO2 in young healthy volunteers using the Kety-Schmidt technique with 133Xe as the inert gas. Measurements were performed during wakefulness, deep sleep (stage 3/4), and rapid-eye-movement (REM) sleep as verified by standard polysomnography...... associated with light anesthesia. During REM sleep (dream sleep) CMRO2 was practically the same as in the awake state. Changes in CBF paralleled changes in CMRO2 during both deep and REM sleep.......It could be expected that the various stages of sleep were reflected in variation of the overall level of cerebral activity and thereby in the magnitude of cerebral metabolic rate of oxygen (CMRO2) and cerebral blood flow (CBF). The elusive nature of sleep imposes major methodological restrictions...

  8. Vasoactive intestinal polypeptide excites medial pontine reticular formation neurons in the brainstem rapid eye movement sleep-induction zone

    DEFF Research Database (Denmark)

    Kohlmeier, Kristi Anne; Reiner, P B

    1999-01-01

    Although it has long been known that microinjection of the cholinergic agonist carbachol into the medial pontine reticular formation (mPRF) induces a state that resembles rapid eye movement (REM) sleep, it is likely that other transmitters contribute to mPRF regulation of behavioral states. A key...... candidate is the peptide vasoactive intestinal polypeptide (VIP), which innervates the mPRF and induces REM sleep when injected into this region of the brainstem. To begin understanding the cellular mechanisms underlying this phenomenon, we examined the effects of VIP on mPRF cells using whole-cell patch...... conclude that VIP excites mPRF neurons by activation of a sodium current. This effect is mediated at least in part by G-protein stimulation of adenylyl cyclase, cAMP, and protein kinase A. These data suggest that VIP may play a physiological role in REM induction by its actions on mPRF neurons....

  9. Automated analysis of connected speech reveals early biomarkers of Parkinson's disease in patients with rapid eye movement sleep behaviour disorder.

    Science.gov (United States)

    Hlavnička, Jan; Čmejla, Roman; Tykalová, Tereza; Šonka, Karel; Růžička, Evžen; Rusz, Jan

    2017-02-02

    For generations, the evaluation of speech abnormalities in neurodegenerative disorders such as Parkinson's disease (PD) has been limited to perceptual tests or user-controlled laboratory analysis based upon rather small samples of human vocalizations. Our study introduces a fully automated method that yields significant features related to respiratory deficits, dysphonia, imprecise articulation and dysrhythmia from acoustic microphone data of natural connected speech for predicting early and distinctive patterns of neurodegeneration. We compared speech recordings of 50 subjects with rapid eye movement sleep behaviour disorder (RBD), 30 newly diagnosed, untreated PD patients and 50 healthy controls, and showed that subliminal parkinsonian speech deficits can be reliably captured even in RBD patients, which are at high risk of developing PD or other synucleinopathies. Thus, automated vocal analysis should soon be able to contribute to screening and diagnostic procedures for prodromal parkinsonian neurodegeneration in natural environments.

  10. Dopamine agonist suppression of rapid-eye-movement sleep is secondary to sleep suppression mediated via limbic structures

    Energy Technology Data Exchange (ETDEWEB)

    Miletich, R.S.

    1985-01-01

    The effects of pergolide, a direct dopamine receptor agonist, on sleep and wakefulness, motor behavior and /sup 3/H-spiperone specific binding in limbic structures and striatum in rats was studied. The results show that pergolide induced a biphasic dose effect, with high doses increasing wakefulness and suppressing sleep while low dose decreased wakefulness, but increased sleep. It was shown that pergolide-induced sleep suppression was blocked by ..cap alpha..-glupenthixol and pimozide, two dopamine receptor antagonists. It was further shown that pergolide merely delayed the rebound resulting from rapid-eye-movement (REM) sleep deprivation, that dopamine receptors stimulation had no direct effect on the period, phase or amplitude of the circadian rhythm of REM sleep propensity and that there was no alteration in the coupling of REM sleep episodes with S/sub 2/ episodes. Rapid-eye-movement sleep deprivation resulted in increased sensitivity to the pergolide-induced wakefulness stimulation and sleep suppression and pergolide-induced motor behaviors of locomotion and head bobbing. /sup 3/H-spiperone specific binding to dopamine receptors was shown to be altered by REM sleep deprivation in the subcortical limbic structures. It is concluded that the REM sleep suppressing action of dopamine receptor stimulation is secondary to sleep suppression per se and not secondary to a unique effect on the REM sleep. Further, it is suggested that the wakefulness stimulating action of dopamine receptor agonists is mediated by activation of the dopamine receptors in the terminal areas of the mesolimbocortical dopamine projection system.

  11. Research on the Features of Chlorophyll-a Derived from RapidEye and EOS/MODIS Data in Chaohu Lake

    International Nuclear Information System (INIS)

    Wen, X; Chen, B; Li, Z; Zhou, Z; Tang, X

    2014-01-01

    Chaohu Lake is one of the largest freshwater lakes in China, however, with the rapid expansion of Hefei, the water environment of Chaohu Lake shows significantly deterioration. In this paper, RapidEye and MODIS imagery were used to monitor the chlorophyll alpha (Chla) distribution in Chaohu Lake. After analyzing the correlation between in-situ measured Chla concentrations and each channel of RapidEye and MODIS imagery, the optimal band combination for the establishment of Chla concentration was determined. For RapidEye imagery, the red edge channel and near infrared channel are relatively more sensitive than other channels. The inversion model using the feature of (B5+B4)/(B2+B1) worked the best with the square value of correlation coefficient reaching up to 0.745. A similar procedure was applied to MODIS imagery. The experiments show that RapidEye with its red edge channel is an effective data source for water environment monitoring, it could provide high spatial resolution of Chla distribution thematic map, MODIS with its higher temporal resolution is also an effective data source in dynamically monitoring water environment. The Chla concentration in the western half of Chao Lake is higher than that in the eastern half

  12. Baseline Levels of Rapid Eye Movement Sleep May Protect Against Excessive Activity in Fear-Related Neural Circuitry.

    Science.gov (United States)

    Lerner, Itamar; Lupkin, Shira M; Sinha, Neha; Tsai, Alan; Gluck, Mark A

    2017-11-15

    Sleep, and particularly rapid eye movement sleep (REM), has been implicated in the modulation of neural activity following fear conditioning and extinction in both human and animal studies. It has long been presumed that such effects play a role in the formation and persistence of posttraumatic stress disorder, of which sleep impairments are a core feature. However, to date, few studies have thoroughly examined the potential effects of sleep prior to conditioning on subsequent acquisition of fear learning in humans. Furthermore, these studies have been restricted to analyzing the effects of a single night of sleep-thus assuming a state-like relationship between the two. In the current study, we used long-term mobile sleep monitoring and functional neuroimaging (fMRI) to explore whether trait-like variations in sleep patterns, measured in advance in both male and female participants, predict subsequent patterns of neural activity during fear learning. Our results indicate that higher baseline levels of REM sleep predict reduced fear-related activity in, and connectivity between, the hippocampus, amygdala and ventromedial PFC during conditioning. Additionally, skin conductance responses (SCRs) were weakly correlated to the activity in the amygdala. Conversely, there was no direct correlation between REM sleep and SCRs, indicating that REM may only modulate fear acquisition indirectly. In a follow-up experiment, we show that these results are replicable, though to a lesser extent, when measuring sleep over a single night just before conditioning. As such, baseline sleep parameters may be able to serve as biomarkers for resilience, or lack thereof, to trauma. SIGNIFICANCE STATEMENT Numerous studies over the past two decades have established a clear role of sleep in fear-learning processes. However, previous work has focused on the effects of sleep following fear acquisition, thus neglecting the potential effects of baseline sleep levels on the acquisition itself. The

  13. Impacts of dust aerosol and adjacency effects on the accuracy of Landsat 8 and RapidEye surface reflectances

    KAUST Repository

    Houborg, Rasmus; McCabe, Matthew

    2017-01-01

    The atmospheric correction of satellite data is challenging over desert agricultural systems, due to the relatively high aerosol optical thicknesses (τ550), bright soils, and a heterogeneous surface reflectance field. Indeed, the contribution of reflected radiation from adjacent pixels scattered into the field of view of a target pixel is considerable and can significantly affect the fidelity of retrieved reflectances. In this study, uncertainties and quantitative errors associated with the atmospheric correction of multi-spectral Landsat 8 and RapidEye data were characterized over a desert agricultural landscape in Saudi Arabia. Surface reflectances were retrieved using an implementation of the 6SV atmospheric correction code, and validated against field collected spectroradiometer measurements over desert, cultivated soil, and vegetated surface targets. A combination of satellite and Aerosol Robotic Network (AERONET) data were used to parameterize aerosol properties and atmospheric state parameters. With optimal specification of τ550 and aerosol optical properties and correction for adjacency effects, the relative Mean Absolute Deviation (MAD) for all bands combined was 5.4% for RapidEye and 6.8% for Landsat 8. However uncertainties associated with satellite-based τ550 retrievals were shown to introduce significant error into the reflectance estimates. With respect to deriving common vegetation indices from corrected reflectance data, the Normalized Difference Vegetation Index (NDVI) was associated with the smallest errors (3–8% MAD). Surface reflectance errors were highest for bands in the visible part of the spectrum, particularly the blue band (5–16%), while there was more consistency within the red-edge (~ 5%) and near-infrared (5–7%). Results were generally better constrained when a τ550-dependent aerosol model for desert dust particles, parameterized on the basis of nearby AERONET site data, was used in place of a generic rural or background

  14. Impacts of dust aerosol and adjacency effects on the accuracy of Landsat 8 and RapidEye surface reflectances

    KAUST Repository

    Houborg, Rasmus

    2017-03-29

    The atmospheric correction of satellite data is challenging over desert agricultural systems, due to the relatively high aerosol optical thicknesses (τ550), bright soils, and a heterogeneous surface reflectance field. Indeed, the contribution of reflected radiation from adjacent pixels scattered into the field of view of a target pixel is considerable and can significantly affect the fidelity of retrieved reflectances. In this study, uncertainties and quantitative errors associated with the atmospheric correction of multi-spectral Landsat 8 and RapidEye data were characterized over a desert agricultural landscape in Saudi Arabia. Surface reflectances were retrieved using an implementation of the 6SV atmospheric correction code, and validated against field collected spectroradiometer measurements over desert, cultivated soil, and vegetated surface targets. A combination of satellite and Aerosol Robotic Network (AERONET) data were used to parameterize aerosol properties and atmospheric state parameters. With optimal specification of τ550 and aerosol optical properties and correction for adjacency effects, the relative Mean Absolute Deviation (MAD) for all bands combined was 5.4% for RapidEye and 6.8% for Landsat 8. However uncertainties associated with satellite-based τ550 retrievals were shown to introduce significant error into the reflectance estimates. With respect to deriving common vegetation indices from corrected reflectance data, the Normalized Difference Vegetation Index (NDVI) was associated with the smallest errors (3–8% MAD). Surface reflectance errors were highest for bands in the visible part of the spectrum, particularly the blue band (5–16%), while there was more consistency within the red-edge (~ 5%) and near-infrared (5–7%). Results were generally better constrained when a τ550-dependent aerosol model for desert dust particles, parameterized on the basis of nearby AERONET site data, was used in place of a generic rural or background

  15. Acute administration of fluoxetine normalizes rapid eye movement sleep abnormality, but not depressive behaviors in olfactory bulbectomized rats.

    Science.gov (United States)

    Wang, Yi-Qun; Tu, Zhi-Cai; Xu, Xing-Yuan; Li, Rui; Qu, Wei-Min; Urade, Yoshihiro; Huang, Zhi-Li

    2012-01-01

    In humans, depression is associated with altered rapid eye movement (REM) sleep. However, the exact nature of the relationship between depressive behaviors and sleep abnormalities is debated. In this study, bilateral olfactory bulbectomy (OBX) was carried out to create a model of depression in rats. The sleep-wake profiles were assayed using a cutting-edge sleep bioassay system, and depressive behaviors were evaluated by open field and forced swimming tests. The monoamine content and monoamine metabolite levels in the brain were determined by a HPLC-electrochemical detection system. OBX rats exhibited a significant increase in REM sleep, especially between 15:00 and 18:00 hours during the light period. Acute treatment with fluoxetine (10 mg/kg, i.p.) immediately abolished the OBX-induced increase in REM sleep, but hyperactivity in the open field test and the time spent immobile in the forced swimming test remained unchanged. Neurochemistry studies revealed that acute administration of fluoxetine increased serotonin (5-HT) levels in the hippocampus, thalamus, and midbrain and decreased levels of the 5-HT metabolite 5-hydroxyindoleacetic acid (5-HIAA). The ratio of 5-HIAA to 5-HT decreased in almost all regions of the brain. These results indicate that acute administration of fluoxetine can reduce the increase in REM sleep but does not change the depressive behaviors in OBX rats, suggesting that there was no causality between REM sleep abnormalities and depressive behaviors in OBX rats. © 2011 The Authors. Journal of Neurochemistry © 2011 International Society for Neurochemistry.

  16. Comparison of rhythmic masticatory muscle activity during non-rapid eye movement sleep in guinea pigs and humans.

    Science.gov (United States)

    Kato, Takafumi; Toyota, Risa; Haraki, Shingo; Yano, Hiroyuki; Higashiyama, Makoto; Ueno, Yoshio; Yano, Hiroshi; Sato, Fumihiko; Yatani, Hirofumi; Yoshida, Atsushi

    2017-09-27

    Rhythmic masticatory muscle activity can be a normal variant of oromotor activity, which can be exaggerated in patients with sleep bruxism. However, few studies have tested the possibility in naturally sleeping animals to study the neurophysiological mechanisms of rhythmic masticatory muscle activity. This study aimed to investigate the similarity of cortical, cardiac and electromyographic manifestations of rhythmic masticatory muscle activity occurring during non-rapid eye movement sleep between guinea pigs and human subjects. Polysomnographic recordings were made in 30 freely moving guinea pigs and in eight healthy human subjects. Burst cycle length, duration and activity of rhythmic masticatory muscle activity were compared with those for chewing. The time between R-waves in the electrocardiogram (RR interval) and electroencephalogram power spectrum were calculated to assess time-course changes in cardiac and cortical activities in relation to rhythmic masticatory muscle activity. In animals, in comparison with chewing, rhythmic masticatory muscle activity had a lower burst activity, longer burst duration and longer cycle length (P motor activation in comparison to human subjects. © 2017 European Sleep Research Society.

  17. Rapid eye movement sleep deprivation disrupts consolidation but not reconsolidation of novel object recognition memory in rats.

    Science.gov (United States)

    Chen, Lin; Tian, Shaowen; Ke, Jie

    2014-03-20

    There is increasing evidence that sleep plays a critical role in memory consolidation. However, there are comparatively few studies that have assessed the relationship between sleep and memory reconsolidation. In the present study, we explored the effects of rapid eye movement sleep deprivation (RSD) on the consolidation (experiment 1) and reconsolidation (experiment 2) of novel object recognition memory in rats. In experiment 1 behavioral procedure involved two training phases: sample and test. Rats were subjected to 6h RSD starting either immediately after sample (exposed to 2 objects) or 6h later. In experiment 2 behavioral procedure involved three training phases: sample, reactivation and test. Rats were subjected to 6h RSD starting either immediately after reactivation (exposed to the same 2 sample objects to reactivate the memory trace) or 6h later. Results from experiment 1 showed that post-sample RSD from 0 to 6h but not 6 to 12h disrupted novel object recognition memory consolidation. However, we found that post-reactivation RSD whether from 0 to 6h or 6 to 12h had no effect on novel object recognition memory reconsolidation in experiment 2. The results indicated that RSD selectively disrupted consolidation of novel object recognition memory, suggesting a dissociation effect of RSD on consolidation and reconsolidation. Copyright © 2014 Elsevier Ireland Ltd. All rights reserved.

  18. Why are seizures rare in rapid eye movement sleep? Review of the frequency of seizures in different sleep stages.

    Science.gov (United States)

    Ng, Marcus; Pavlova, Milena

    2013-01-01

    Since the formal characterization of sleep stages, there have been reports that seizures may preferentially occur in certain phases of sleep. Through ascending cholinergic connections from the brainstem, rapid eye movement (REM) sleep is physiologically characterized by low voltage fast activity on the electroencephalogram, REMs, and muscle atonia. Multiple independent studies confirm that, in REM sleep, there is a strikingly low proportion of seizures (~1% or less). We review a total of 42 distinct conventional and intracranial studies in the literature which comprised a net of 1458 patients. Indexed to duration, we found that REM sleep was the most protective stage of sleep against focal seizures, generalized seizures, focal interictal discharges, and two particular epilepsy syndromes. REM sleep had an additional protective effect compared to wakefulness with an average 7.83 times fewer focal seizures, 3.25 times fewer generalized seizures, and 1.11 times fewer focal interictal discharges. In further studies REM sleep has also demonstrated utility in localizing epileptogenic foci with potential translation into postsurgical seizure freedom. Based on emerging connectivity data in sleep, we hypothesize that the influence of REM sleep on seizures is due to a desynchronized EEG pattern which reflects important connectivity differences unique to this sleep stage.

  19. Effects of partial sleep deprivation on slow waves during non-rapid eye movement sleep: A high density EEG investigation.

    Science.gov (United States)

    Plante, David T; Goldstein, Michael R; Cook, Jesse D; Smith, Richard; Riedner, Brady A; Rumble, Meredith E; Jelenchick, Lauren; Roth, Andrea; Tononi, Giulio; Benca, Ruth M; Peterson, Michael J

    2016-02-01

    Changes in slow waves during non-rapid eye movement (NREM) sleep in response to acute total sleep deprivation are well-established measures of sleep homeostasis. This investigation utilized high-density electroencephalography (hdEEG) to examine topographic changes in slow waves during repeated partial sleep deprivation. Twenty-four participants underwent a 6-day sleep restriction protocol. Spectral and period-amplitude analyses of sleep hdEEG data were used to examine changes in slow wave energy, count, amplitude, and slope relative to baseline. Changes in slow wave energy were dependent on the quantity of NREM sleep utilized for analysis, with widespread increases during sleep restriction and recovery when comparing data from the first portion of the sleep period, but restricted to recovery sleep if the entire sleep episode was considered. Period-amplitude analysis was less dependent on the quantity of NREM sleep utilized, and demonstrated topographic changes in the count, amplitude, and distribution of slow waves, with frontal increases in slow wave amplitude, numbers of high-amplitude waves, and amplitude/slopes of low amplitude waves resulting from partial sleep deprivation. Topographic changes in slow waves occur across the course of partial sleep restriction and recovery. These results demonstrate a homeostatic response to partial sleep loss in humans. Copyright © 2015 International Federation of Clinical Neurophysiology. Published by Elsevier Ireland Ltd. All rights reserved.

  20. Rapid eye movement sleep behavior disorder: devising controlled active treatment studies for symptomatic and neuroprotective therapy--a consensus statement from the International Rapid Eye Movement Sleep Behavior Disorder Study Group.

    Science.gov (United States)

    Schenck, C H; Montplaisir, J Y; Frauscher, B; Hogl, B; Gagnon, J-F; Postuma, R; Sonka, K; Jennum, P; Partinen, M; Arnulf, I; Cochen de Cock, V; Dauvilliers, Y; Luppi, P-H; Heidbreder, A; Mayer, G; Sixel-Döring, F; Trenkwalder, C; Unger, M; Young, P; Wing, Y K; Ferini-Strambi, L; Ferri, R; Plazzi, G; Zucconi, M; Inoue, Y; Iranzo, A; Santamaria, J; Bassetti, C; Möller, J C; Boeve, B F; Lai, Y Y; Pavlova, M; Saper, C; Schmidt, P; Siegel, J M; Singer, C; St Louis, E; Videnovic, A; Oertel, W

    2013-08-01

    We aimed to provide a consensus statement by the International Rapid Eye Movement Sleep Behavior Disorder Study Group (IRBD-SG) on devising controlled active treatment studies in rapid eye movement sleep behavior disorder (RBD) and devising studies of neuroprotection against Parkinson disease (PD) and related neurodegeneration in RBD. The consensus statement was generated during the fourth IRBD-SG symposium in Marburg, Germany in 2011. The IRBD-SG identified essential methodologic components for a randomized trial in RBD, including potential screening and diagnostic criteria, inclusion and exclusion criteria, primary and secondary outcomes for symptomatic therapy trials (particularly for melatonin and clonazepam), and potential primary and secondary outcomes for eventual trials with disease-modifying and neuroprotective agents. The latter trials are considered urgent, given the high conversion rate from idiopathic RBD (iRBD) to Parkinsonian disorders (i.e., PD, dementia with Lewy bodies [DLB], multiple system atrophy [MSA]). Six inclusion criteria were identified for symptomatic therapy and neuroprotective trials: (1) diagnosis of RBD needs to satisfy the International Classification of Sleep Disorders, second edition, (ICSD-2) criteria; (2) minimum frequency of RBD episodes should preferably be ⩾2 times weekly to allow for assessment of change; (3) if the PD-RBD target population is included, it should be in the early stages of PD defined as Hoehn and Yahr stages 1-3 in Off (untreated); (4) iRBD patients with soft neurologic dysfunction and with operational criteria established by the consensus of study investigators; (5) patients with mild cognitive impairment (MCI); and (6) optimally treated comorbid OSA. Twenty-four exclusion criteria were identified. The primary outcome measure for RBD treatment trials was determined to be the Clinical Global Impression (CGI) efficacy index, consisting of a four-point scale with a four-point side-effect scale. Assessment of

  1. A phenolic acid based colourimetric 'naked-eye' chemosensor for the rapid detection of Cu(II) ions

    Science.gov (United States)

    Sengupta, Priti; Ganguly, Aniruddha; Bose, Adity

    2018-06-01

    The crucial role of chemosensor for the immediate recognition of environment pollutant motivates the researchers to develop variety of sensing protocols. Of various chemosensory protocols, the colour change observed by the naked eye is considered to be a conceivable and on-site way to indicate the presence of an analyte. We herein report a colourimetric and commercially available absorption probe, sinapic acid (SA) that is completely ready to use for "on-site" visual determination of copper ions. The molecule, SA is well-known phenolic acid, often utilized for its antibacterial activity. In this work, for the first time, we are exploring its ability to work as an efficient Cu2+ sensor. This sensor molecule selectively detected Cu2+ ions by changing its colour from colourless to pink within detection limit of 64.5 nM, which is much lower than other reported sensor molecules and the suggested limit by World Health Organization (WHO) and U. S. Environmental Protection Agency (EPA) guidelines. The sensing mechanism was investigated through UV-vis and 1H NMR titration along with ESI-MS spectroscopy and further confirmed by DFT computational studies. Studies revealed the participation of hydroxyl group (sbnd OH) and methoxy group (sbnd OMe) of SA in complexation with Cu2+. The binding stoichiometry of SA to Cu2+ was found to be 1:2 through Job's plot and ESI-MS analysis. Importantly, paper strips of SA were prepared which could be used for a rapid "on-site" determination of Cu2+ containing samples.

  2. Magnetic Resonance Imaging Biomarkers to Assess Substantia Nigra Damage in Idiopathic Rapid Eye Movement Sleep Behavior Disorder.

    Science.gov (United States)

    Pyatigorskaya, Nadya; Gaurav, Rahul; Arnaldi, Dario; Leu-Semenescu, Smaranda; Yahia-Cherif, Lydia; Valabregue, Romain; Vidailhet, Marie; Arnulf, Isabelle; Lehéricy, Stephane

    2017-11-01

    Idiopathic rapid eye movement sleep behavior disorder (iRBD) is considered to be a prodromal stage of Parkinson's disease (PD). At PD onset, 40 to 70% of the dopaminergic neurons in the substantia nigra (SN) are already lost. Thus, milder SN damage is expected in participants with iRBD. We aimed to quantify SN damage in participants with iRBD using multimodal magnetic resonance imaging (MRI) and to determine biomarker efficacy in preclinical Parkinsonism. Nineteen participants with iRBD and 18 controls underwent 3-Tesla MRI, including diffusion tensor imaging, neuromelanin (NM)-sensitive imaging, and T2* mapping. Regions of interest in the SN area were drawn in NM-sensitive and T2-weighted images. The volume and normalized signal intensity in NM-sensitive images, R2*, and diffusion tensor measures were quantified in the SN. Additionally, two raters performed visual analysis of the SN using the NM-sensitive images. Participants with iRBD showed a reduction in the NM-sensitive volume and signal intensity and a decrease in fractional anisotropy (FA) versus controls, but showed no differences in axial, radial, or mean diffusivity or in R2*. For NM-sensitive volume and signal intensity, the receiver operating characteristic analysis discriminated between participants with iRBD and controls with a diagnostic accuracy of 0.86 and 0.79, respectively, whereas the accuracy was 0.77 for FA. The three biomarkers had a combined accuracy of 0.92. The fraction of participants correctly characterized by visual assessment was 0.81. NM-sensitive imaging and FA allowed for the detection of SN damage in participants with iRBD with good diagnostic accuracy. These measures may represent valuable biomarkers for prodromal Parkinsonism. © Sleep Research Society 2017. Published by Oxford University Press on behalf of the Sleep Research Society. All rights reserved. For permissions, please e-mail journals.permissions@oup.com.

  3. Time-of-night variations in the story-like organization of dream experience developed during rapid eye movement sleep.

    Science.gov (United States)

    Cipolli, Carlo; Guazzelli, Mario; Bellucci, Claudia; Mazzetti, Michela; Palagini, Laura; Rosenlicht, Nicholas; Feinberg, Irwin

    2015-04-01

    This study aimed to investigate the cycles (2nd/4th) and duration-related (5/10 min) variations in the story-like organization of dream experience elaborated during rapid eye movement (REM) sleep. Dream reports were analysed using story grammar rules. Reports were provided by those subjects (14 of 22) capable of reporting a dream after each of the four awakenings provoked in 2 consecutive nights during REM sleep of the 2nd and 4th cycles, after periods of either 5 or 10 min, counterbalanced across the nights. Two researchers who were blind as to the sleep condition scored the dream reports independently. The values of the indicators of report length (measured as value of total word count) and of story-like organization of dream reports were matched taking time-of-night (2nd and 4th cycles) and REM duration (5 versus 10 min) as factors. Two-way analyses of variance showed that report length increased significantly in 4th-cycle REM sleep and nearly significantly for longer REM duration, whereas the number of dream-stories per report did not vary. The indices of sequential (number of statements describing the event structure developed in the story) and hierarchical (number of episodes per story) organization increased significantly only in dream-stories reported after 10 min of 4th-cycle REM sleep. These findings indicate that the characteristics of structural organization of dream-stories vary along with time of night, and suggest that the elaboration of a long and complex dream-story requires a fairly long time and the availability of a great amount of cognitive resources to maintain its continuity and coherence. © 2014 European Sleep Research Society.

  4. Study on microstructure of corpus striatum in patients with idiopathic rapid eye movement sleep behavior disorder using magnetic resonance imaging

    Directory of Open Access Journals (Sweden)

    Ya-meng ZHANG

    2017-07-01

    Full Text Available Objective To investigate the structure of corpus striatum and the integrity of white matter fiber in patients with Parkinson's disease (PD and idiopathic rapid eye movement sleep behavior disorder (iRBD.  Methods Twelve patients with iRBD, 12 patients with PD and 10 healthy subjects that were well matched in gender, age and education were enrolled in this study. Head MRI examination was performed to all subjects to observe the changes of corpus striatum structure (the gray matter volume and the integrity of white matter fiber [fractional anisotropy (FA] by combining voxel?based morphometry (VBM and diffusion tensor imaging (DTI.  Results Compared with healthy subjects, the gray matter volume of left caudate nucleus was significantly decreased (P < 0.005, and FA values of left caudate nucleus (P < 0.005, right caudate nucleus (P < 0.001 and right putamen (P < 0.05 were all significantly reduced in iRBD patients; FA value of right putamen was significantly decreased in PD patients (P < 0.05. Compared with PD patients, the gray matter volume of left caudate nucleus of iRBD patients was significantly reduced (P < 0.001, FA values of left caudate nucleus (P < 0.01 and right caudate nucleus (P < 0.005 of iRBD patients were significantly reduced.  Conclusions There is atrophy of gray matter volume and extensive white matter fiber impairment in corpus striatum of patients with iRBD, and the white matter fiber impairment was similar to PD, which provides an anatomical evidence for iRBD being presymptom of PD. DOI: 10.3969/j.issn.1672-6731.2017.05.008

  5. Prevalence of rapid eye movement sleep behavior disorder (RBD) in Parkinson's disease: a meta and meta-regression analysis.

    Science.gov (United States)

    Zhang, Xiaona; Sun, Xiaoxuan; Wang, Junhong; Tang, Liou; Xie, Anmu

    2017-01-01

    Rapid eye movement sleep behavior disorder (RBD) is thought to be one of the most frequent preceding symptoms of Parkinson's disease (PD). However, the prevalence of RBD in PD stated in the published studies is still inconsistent. We conducted a meta and meta-regression analysis in this paper to estimate the pooled prevalence. We searched the electronic databases of PubMed, ScienceDirect, EMBASE and EBSCO up to June 2016 for related articles. STATA 12.0 statistics software was used to calculate the available data from each research. The prevalence of RBD in PD patients in each study was combined to a pooled prevalence with a 95 % confidence interval (CI). Subgroup analysis and meta-regression analysis were performed to search for the causes of the heterogeneity. A total of 28 studies with 6869 PD cases were deemed eligible and included in our meta-analysis based on the inclusion and exclusion criteria. The pooled prevalence of RBD in PD was 42.3 % (95 % CI 37.4-47.1 %). In subgroup analysis and meta-regression analysis, we found that the important causes of heterogeneity were the diagnosis criteria of RBD and age of PD patients (P = 0.016, P = 0.019, respectively). The results indicate that nearly half of the PD patients are suffering from RBD. Older age and longer duration are risk factors for RBD in PD. We can use the minimal diagnosis criteria for RBD according to the International Classification of Sleep Disorders to diagnose RBD patients in our daily work if polysomnography is not necessary.

  6. Honokiol promotes non-rapid eye movement sleep via the benzodiazepine site of the GABA(A) receptor in mice.

    Science.gov (United States)

    Qu, Wei-Min; Yue, Xiao-Fang; Sun, Yu; Fan, Kun; Chen, Chang-Rui; Hou, Yi-Ping; Urade, Yoshihiro; Huang, Zhi-Li

    2012-10-01

    Decoctions of the Chinese herb houpu contain honokiol and are used to treat a variety of mental disorders, including depression. Depression commonly presents alongside sleep disorders and sleep disturbances, which appear to be a major risk factor for depression. Here, we have evaluated the somnogenic effect of honokiol and the mechanisms involved. Honokiol was administered i.p. at 20:00 h in mice. Flumazenil, an antagonist at the benzodiazepine site of the GABA(A) receptor, was administered i.p. 15 min before honokiol. The effects of honokiol were measured by EEG and electromyogram (EMG), c-Fos expression and in vitro electrophysiology. Honokiol (10 and 20 mg·kg⁻¹) significantly shortened the sleep latency to non-rapid eye movement (non-REM, NREM) sleep and increased the amount of NREM sleep. Honokiol increased the number of state transitions from wakefulness to NREM sleep and, subsequently, from NREM sleep to wakefulness. However, honokiol had no effect on either the amount of REM sleep or EEG power density of both NREM and REM sleep. Honokiol increased c-Fos expression in ventrolateral preoptic area (VLPO) neurons, as examined by immunostaining, and excited sleep-promoting neurons in the VLPO by whole-cell patch clamping in the brain slice. Pretreatment with flumazenil abolished the somnogenic effects and activation of the VLPO neurons by honokiol. Honokiol promoted NREM sleep by modulating the benzodiazepine site of the GABA(A) receptor, suggesting potential applications in the treatment of insomnia, especially for patients who experience difficulty in falling and staying asleep. © 2012 The Authors. British Journal of Pharmacology © 2012 The British Pharmacological Society.

  7. Application of a regularized model inversion system (REGFLEC) to multi-temporal RapidEye imagery for retrieving vegetation characteristics

    KAUST Repository

    Houborg, Rasmus

    2015-10-14

    Accurate retrieval of canopy biophysical and leaf biochemical constituents from space observations is critical to diagnosing the functioning and condition of vegetation canopies across spatio-temporal scales. Retrieved vegetation characteristics may serve as important inputs to precision farming applications and as constraints in spatially and temporally distributed model simulations of water and carbon exchange processes. However significant challenges remain in the translation of composite remote sensing signals into useful biochemical, physiological or structural quantities and treatment of confounding factors in spectrum-trait relations. Bands in the red-edge spectrum have particular potential for improving the robustness of retrieved vegetation properties. The development of observationally based vegetation retrieval capacities, effectively constrained by the enhanced information content afforded by bands in the red-edge, is a needed investment towards optimizing the benefit of current and future satellite sensor systems. In this study, a REGularized canopy reFLECtance model (REGFLEC) for joint leaf chlorophyll (Chll) and leaf area index (LAI) retrieval is extended to sensor systems with a band in the red-edge region for the first time. Application to time-series of 5 m resolution multi-spectral RapidEye data is demonstrated over an irrigated agricultural region in central Saudi Arabia, showcasing the value of satellite-derived crop information at this fine scale for precision management. Validation against in-situ measurements in fields of alfalfa, Rhodes grass, carrot and maize indicate improved accuracy of retrieved vegetation properties when exploiting red-edge information in the model inversion process. © (2015) COPYRIGHT Society of Photo-Optical Instrumentation Engineers (SPIE).

  8. Probable rapid eye movement sleep behavior disorder, nocturnal disturbances and quality of life in patients with Parkinson’s disease: a case-controlled study using the rapid eye movement sleep behavior disorder screening questionnaire

    Directory of Open Access Journals (Sweden)

    Suzuki Keisuke

    2013-02-01

    Full Text Available Abstract Background Increasing evidence provides a clear association between rapid eye movement sleep behavior disorders (RBD and Parkinson’s disease (PD, but the clinical features that determine the co-morbidity of RBD and PD are not yet fully understood. Methods We evaluated the characteristics of nocturnal disturbances and other motor and non-motor features related to RBD in patients with PD and the impact of RBD on their quality of life. Probable RBD (pRBD was evaluated using the Japanese version of the RBD screening questionnaire (RBDSQ-J. Results A significantly higher frequency of pRBD was observed in PD patients than in the controls (RBDSQ-J ≥ 5 or ≥ 6: 29.0% vs. 8.6%; 17.2% vs. 2.2%, respectively. After excluding restless legs syndrome and snorers in the PD patients, the pRBD group (RBDSQ-J≥5 showed higher scores compared with the non-pRBD group on the Parkinson’s disease sleep scale-2 (PDSS-2 total and three-domain scores. Early morning dystonia was more frequent in the pRBD group. The Parkinson’s Disease Questionnaire (PDQ-39 domain scores for cognition and emotional well-being were higher in the patients with pRBD than in the patients without pRBD. There were no differences between these two groups with respect to the clinical subtype, disease severity or motor function. When using a cut-off of RBDSQ-J = 6, a similar trend was observed for the PDSS-2 and PDQ-39 scores. Patients with PD and pRBD had frequent sleep onset insomnia, distressing dreams and hallucinations. The stepwise linear regression analysis showed that the PDSS-2 domain “motor symptoms at night”, particularly the PDSS sub-item 6 “distressing dreams”, was the only predictor of RBDSQ-J in PD. Conclusion Our results indicate a significant impact of RBD co-morbidity on night-time disturbances and quality of life in PD, particularly on cognition and emotional well-being. RBDSQ may be a useful tool for not only screening RBD in PD patients

  9. A novel non-rapid-eye movement and rapid-eye-movement parasomnia with sleep breathing disorder associated with antibodies to IgLON5: a case series, characterisation of the antigen, and post-mortem study.

    Science.gov (United States)

    Sabater, Lidia; Gaig, Carles; Gelpi, Ellen; Bataller, Luis; Lewerenz, Jan; Torres-Vega, Estefanía; Contreras, Angeles; Giometto, Bruno; Compta, Yaroslau; Embid, Cristina; Vilaseca, Isabel; Iranzo, Alex; Santamaría, Joan; Dalmau, Josep; Graus, Francesc

    2014-06-01

    Autoimmunity might be associated with or implicated in sleep and neurodegenerative disorders. We aimed to describe the features of a novel neurological syndrome associated with prominent sleep dysfunction and antibodies to a neuronal antigen. In this observational study, we used clinical and video polysomnography to identify a novel sleep disorder in three patients referred to the Sleep Unit of Hospital Clinic, University of Barcelona, Spain, for abnormal sleep behaviours and obstructive sleep apnoea. These patients had antibodies against a neuronal surface antigen, which were also present in five additional patients referred to our laboratory for antibody studies. These five patients had been assessed with polysomnography, which was done in our sleep unit in one patient and the recording reviewed in a second patient. Two patients underwent post-mortem brain examination. Immunoprecipitation and mass spectrometry were used to characterise the antigen and develop an assay for antibody testing. Serum or CSF from 298 patients with neurodegenerative, sleep, or autoimmune disorders served as control samples. All eight patients (five women; median age at disease onset 59 years [range 52-76]) had abnormal sleep movements and behaviours and obstructive sleep apnoea, as confirmed by polysomnography. Six patients had chronic progression with a median duration from symptom onset to death or last visit of 5 years (range 2-12); in four the sleep disorder was the initial and most prominent feature, and in two it was preceded by gait instability followed by dysarthria, dysphagia, ataxia, or chorea. Two patients had a rapid progression with disequilibrium, dysarthria, dysphagia, and central hypoventilation, and died 2 months and 6 months, respectively, after symptom onset. In five of five patients, video polysomnography showed features of obstructive sleep apnoea, stridor, and abnormal sleep architecture (undifferentiated non-rapid-eye-movement [non-REM] sleep or poorly structured

  10. The Clinical Phenotype of Idiopathic Rapid Eye Movement Sleep Behavior Disorder at Presentation: A Study in 203 Consecutive Patients.

    Science.gov (United States)

    Fernández-Arcos, Ana; Iranzo, Alex; Serradell, Mónica; Gaig, Carles; Santamaria, Joan

    2016-01-01

    To describe the clinical phenotype of idiopathic rapid eye movement (REM) sleep behavior disorder (IRBD) at presentation in a sleep center. Clinical history review of 203 consecutive patients with IRBD identified between 1990 and 2014. IRBD was diagnosed by clinical history plus video-polysomnographic demonstration of REM sleep with increased electromyographic activity linked to abnormal behaviors. Patients were 80% men with median age at IRBD diagnosis of 68 y (range, 50-85 y). In addition to the already known clinical picture of IRBD, other important features were apparent: 44% of the patients were not aware of their dream-enactment behaviors and 70% reported good sleep quality. In most of these cases bed partners were essential to convince patients to seek medical help. In 11% IRBD was elicited only after specific questioning when patients consulted for other reasons. Seven percent did not recall unpleasant dreams. Leaving the bed occurred occasionally in 24% of subjects in whom dementia with Lewy bodies often developed eventually. For the correct diagnosis of IRBD, video-polysomnography had to be repeated in 16% because of insufficient REM sleep or electromyographic artifacts from coexistent apneas. Some subjects with comorbid obstructive sleep apnea reported partial improvement of RBD symptoms following continuous positive airway pressure therapy. Lack of therapy with clonazepam resulted in an increased risk of sleep related injuries. Synucleinopathy was frequently diagnosed, even in patients with mild severity or uncommon IRBD presentations (e.g., patients who reported sleeping well, onset triggered by a life event, nocturnal ambulation) indicating that the development of a neurodegenerative disease is independent of the clinical presentation of IRBD. We report the largest IRBD cohort observed in a single center to date and highlight frequent features that were not reported or not sufficiently emphasized in previous publications. Physicians should be aware of

  11. Rapid eye movement (REM sleep deprivation reduces rat frontal cortex acetylcholinesterase (EC 3.1.1.7 activity

    Directory of Open Access Journals (Sweden)

    Camarini R.

    1997-01-01

    Full Text Available Rapid eye movement (REM sleep deprivation induces several behavioral changes. Among these, a decrease in yawning behavior produced by low doses of cholinergic agonists is observed which indicates a change in brain cholinergic neurotransmission after REM sleep deprivation. Acetylcholinesterase (Achase controls acetylcholine (Ach availability in the synaptic cleft. Therefore, altered Achase activity may lead to a change in Ach availability at the receptor level which, in turn, may result in modification of cholinergic neurotransmission. To determine if REM sleep deprivation would change the activity of Achase, male Wistar rats, 3 months old, weighing 250-300 g, were deprived of REM sleep for 96 h by the flower-pot technique (N = 12. Two additional groups, a home-cage control (N = 6 and a large platform control (N = 6, were also used. Achase was measured in the frontal cortex using two different methods to obtain the enzyme activity. One method consisted of the obtention of total (900 g supernatant, membrane-bound (100,000 g pellet and soluble (100,000 g supernatant Achase, and the other method consisted of the obtention of a fraction (40,000 g pellet enriched in synaptic membrane-bound enzyme. In both preparations, REM sleep deprivation induced a significant decrease in rat frontal cortex Achase activity when compared to both home-cage and large platform controls. REM sleep deprivation induced a significant decrease of 16% in the membrane-bound Achase activity (nmol thiocholine formed min-1 mg protein-1 in the 100,000 g pellet enzyme preparation (home-cage group 152.1 ± 5.7, large platform group 152.7 ± 24.9 and REM sleep-deprived group 127.9 ± 13.8. There was no difference in the soluble enzyme activity. REM sleep deprivation also induced a significant decrease of 20% in the enriched synaptic membrane-bound Achase activity (home-cage group 126.4 ± 21.5, large platform group 127.8 ± 20.4, REM sleep-deprived group 102.8 ± 14.2. Our results

  12. Dissociating the contributions of slow-wave sleep and rapid eye movement sleep to emotional item and source memory.

    Science.gov (United States)

    Groch, S; Zinke, K; Wilhelm, I; Born, J

    2015-07-01

    Sleep benefits the consolidation of emotional memories, and this influence is commonly attributed to the rapid eye movement (REM) stage of sleep. However, the contributions of sleep stages to memory for an emotional episode may differ for the event per se (i.e., item memory), and the context in which it occurred (source memory). Here, we examined the effects of slow wave sleep (SWS) and REM sleep on the consolidation of emotionally negative and neutral item (picture recognition) and source memory (recall of picture-location and picture-frame color association) in humans. In Study 1, the participants (n=18) learned 48 negative and 48 neutral pictures which were presented at specific locations and preceded by colored frames that had to be associated with the picture. In a within-subject design, learning was either followed by a 3-h early-night SWS-rich or by a late-night REM sleep-rich retention interval, then retrieval was tested. Only after REM-rich sleep, and not after SWS-rich sleep, was there a significant emotional enhancement, i.e., a significantly superior retention of emotional over neutral pictures. On the other hand, after SWS-rich sleep the retention of picture-frame color associations was better than after REM-rich sleep. However, this benefit was observed only for neutral pictures; and it was completely absent for the emotional pictures. To examine whether this absent benefit reflected a suppressive effect of emotionality on associations of minor task relevance, in Study 2 we manipulated the relevance of the picture-frame color association by combining it with information about monetary reward, following otherwise comparable procedures. Here, rewarded picture-frame color associations were equally well retained over SWS-rich early sleep no matter if the frames were associated with emotional or neutral pictures. Results are consistent with the view that REM sleep favors the emotional enhancement of item memory whereas SWS appears to contribute primarily

  13. The relative timing between eye and hand rapid sequential pointing is affected by time pressure, but not by advance knowledge

    NARCIS (Netherlands)

    Deconinck, F.; van Polanen, V.; Savelsbergh, G.J.P.; Bennett, S.

    2011-01-01

    The present study examined the effect of timing constraints and advance knowledge on eye-hand coordination strategy in a sequential pointing task. Participants were required to point at two successively appearing targets on a screen while the inter-stimulus interval (ISI) and the trial order were

  14. Avoidance of a moving threat in the common chameleon (Chamaeleo chamaeleon): rapid tracking by body motion and eye use.

    Science.gov (United States)

    Lev-Ari, Tidhar; Lustig, Avichai; Ketter-Katz, Hadas; Baydach, Yossi; Katzir, Gadi

    2016-08-01

    A chameleon (Chamaeleo chamaeleon) on a perch responds to a nearby threat by moving to the side of the perch opposite the threat, while bilaterally compressing its abdomen, thus minimizing its exposure to the threat. If the threat moves, the chameleon pivots around the perch to maintain its hidden position. How precise is the body rotation and what are the patterns of eye movement during avoidance? Just-hatched chameleons, placed on a vertical perch, on the side roughly opposite to a visual threat, adjusted their position to precisely opposite the threat. If the threat were moved on a horizontal arc at angular velocities of up to 85°/s, the chameleons co-rotated smoothly so that (1) the angle of the sagittal plane of the head relative to the threat and (2) the direction of monocular gaze, were positively and significantly correlated with threat angular position. Eye movements were role-dependent: the eye toward which the threat moved maintained a stable gaze on it, while the contralateral eye scanned the surroundings. This is the first description, to our knowledge, of such a response in a non-flying terrestrial vertebrate, and it is discussed in terms of possible underlying control systems.

  15. Estimation and Validation of RapidEye-Based Time-Series of Leaf Area Index for Winter Wheat in the Rur Catchment (Germany

    Directory of Open Access Journals (Sweden)

    Muhammad Ali

    2015-03-01

    Full Text Available Leaf Area Index (LAI is an important variable for numerous processes in various disciplines of bio- and geosciences. In situ measurements are the most accurate source of LAI among the LAI measuring methods, but the in situ measurements have the limitation of being labor intensive and site specific. For spatial-explicit applications (from regional to continental scales, satellite remote sensing is a promising source for obtaining LAI with different spatial resolutions. However, satellite-derived LAI measurements using empirical models require calibration and validation with the in situ measurements. In this study, we attempted to validate a direct LAI retrieval method from remotely sensed images (RapidEye with in situ LAI (LAIdestr. Remote sensing LAI (LAIrapideye were derived using different vegetation indices, namely SAVI (Soil Adjusted Vegetation Index and NDVI (Normalized Difference Vegetation Index. Additionally, applicability of the newly available red-edge band (RE was also analyzed through Normalized Difference Red-Edge index (NDRE and Soil Adjusted Red-Edge index (SARE. The LAIrapideye obtained from vegetation indices with red-edge band showed better correlation with LAIdestr (r = 0.88 and Root Mean Square Devation, RMSD = 1.01 & 0.92. This study also investigated the need to apply radiometric/atmospheric correction methods to the time-series of RapidEye Level 3A data prior to LAI estimation. Analysis of the the RapidEye Level 3A data set showed that application of the radiometric/atmospheric correction did not improve correlation of the estimated LAI with in situ LAI.

  16. The dream-lag effect: selective processing of personally significant events during Rapid Eye Movement sleep, but not during Slow Wave Sleep

    OpenAIRE

    van Rijn, E.; Eichenlaub, J.-B.; Lewis, Penelope A.; Walker, M.P.; Gaskell, M.G.; Malinowski, J.E.; Blagrove, M.

    2015-01-01

    Incorporation of details from waking life events into Rapid Eye Movement (REM) sleep dreams has been found to be highest on the night after, and then 5-7 nights after events (termed, respectively, the day-residue and dream-lag effects). In experiment 1, 44 participants kept a daily log for 10. days, reporting major daily activities (MDAs), personally significant events (PSEs), and major concerns (MCs). Dream reports were collected from REM and Slow Wave Sleep (SWS) in the laboratory, or from ...

  17. In vivo evaluation and in-depth pharmaceutical characterization of a rapidly dissolving solid ocular matrix for the topical delivery of timolol maleate in the rabbit eye model.

    Science.gov (United States)

    Moosa, Raeesa M; Choonara, Yahya E; du Toit, Lisa C; Tomar, Lomas K; Tyagi, Charu; Kumar, Pradeep; Carmichael, Trevor R; Pillay, Viness

    2014-05-15

    The purpose of this study was to investigate the in-depth pharmaceutical properties and in vivo behavior of a novel lyophilized rapidly dissolving solid ocular matrix (RD-SOM) as a 'solid eye drop' formulation comprising timolol maleate as the model drug. Thermal and molecular transition analysis displayed similar findings with no incompatibility between formulation components. Porositometric studies confirmed the presence of interconnecting pores across the matrix surface. The HETCAM test indicated an irritation score of 0 with the inference of good tolerability for the RD-SOM in the New Zealand White albino rabbit eye model. Ex vivo permeation across excised rabbit cornea showed an improved steady state drug flux (0.00052 mg cm(-2)min(-1)) and permeability co-efficient (1.7 × 10(-4)cmmin(-1)) for the RD-SOM compared to pure drug and a marketed eye drop preparation. UPLC analysis quantitatively separated timolol maleate and the internal standard (diclofenac sodium) and gamma irradiation was used as a terminal sterilization procedure. In vivo results revealed a peak concentration of timolol was reached at 104.9 min. In the case of a typical eye drop formulation a lower Cmax was obtained (1.97 ug/mL). Level A point-to-point IVIVC plots via the Wagner-Nelson method revealed a satisfactory R(2) value of 0.84. In addition, the biodegradability and ocular compatibility of the RD-SOM was confirmed by histopathological toxicity studies. Copyright © 2014 Elsevier B.V. All rights reserved.

  18. PV module mounting method and mounting assembly

    Science.gov (United States)

    Lenox, Carl J.S.; Johnson, Kurt M.

    2013-04-23

    A method for mounting PV modules to a deck includes selecting PV module layout pattern so that adjacent PV module edges are spaced apart. PV mounting and support assemblies are secured to the deck according to the layout pattern using fasteners extending into the deck. The PV modules are placed on the PV mounting and support assemblies. Retaining elements are located over and secured against the upper peripheral edge surfaces of the PV modules so to secure them to the deck with the peripheral edges of the PV modules spaced apart from the deck. In some examples a PV module mounting assembly, for use on a shingled deck, comprises flashing, a base mountable on the flashing, a deck-penetrating fastener engageable with the base and securable to the deck so to secure the flashing and the base to the shingled deck, and PV module mounting hardware securable to the base.

  19. Magnetic core mounting system

    Science.gov (United States)

    Ronning, Jeffrey J.

    2002-01-01

    A mounting apparatus for an electromagnetic device such as a transformer of inductor includes a generally planar metallic plate as a first heat sink, and a metallic mounting cup as a second heat sink. The mounting cup includes a cavity configured to receive the electromagnetic device, the cavity being defined by a base, and an axially-extending annular sidewall extending from the base to a flange portion of the mounting cup. The mounting cup includes first and second passages for allowing the leads of first and second windings of the electromagnetic device to be routed out of the cavity. The cavity is filled with a polyurethane potting resin, and the mounting cup, including the potted electromagnetic device, is mounted to the plate heat sink using fasteners. The mounting cup, which surrounds the electromagnetic device, in combination with the potting resin provides improved thermal transfer to the plate heat sink, as well as providing resistance to vibration and shocks.

  20. Dry Eye

    Science.gov (United States)

    ... Eye » Facts About Dry Eye Listen Facts About Dry Eye Fact Sheet Blurb The National Eye Institute (NEI) ... and their families search for general information about dry eye. An eye care professional who has examined the ...

  1. The King-Devick (K-D) test of rapid eye movements: a bedside correlate of disability and quality of life in MS.

    Science.gov (United States)

    Moster, Stephen; Wilson, James A; Galetta, Steven L; Balcer, Laura J

    2014-08-15

    We investigated the King-Devick (K-D) test of rapid number naming as a visual performance measure in a cohort of patients with multiple sclerosis (MS). In this cross-sectional study, 81 patients with MS and 20 disease-free controls from an ongoing study of visual outcomes underwent K-D testing. A test of rapid number naming, K-D requires saccadic eye movements as well as intact vision, attention and concentration. To perform the K-D test, participants are asked to read numbers aloud as quickly as possible from three test cards; the sum of the three test card times in seconds constitutes the summary score. High-contrast visual acuity (VA), low-contrast letter acuity (1.25% and 2.5% levels), retinal nerve fiber layer (RNFL) thickness by optical coherence tomography (OCT), MS Functional Composite (MSFC) and vision-specific quality of life (QOL) measures (25-Item NEI Visual Functioning Questionnaire [NEI-VFQ-25] and 10-Item Neuro-Ophthalmic Supplement) were also assessed. K-D time scores in the MS cohort (total time to read the three test cards) were significantly higher (worse) compared to those for disease-free controls (P=0.003, linear regression, accounting for age). Within the MS cohort, higher K-D scores were associated with worse scores for the NEI-VFQ-25 composite (Paccounting for age and within-patient, inter-eye correlations). Patients with a history of optic neuritis (ON) had increased (worse) K-D scores. Patients who classified their work disability status as disabled (receiving disability pension) did worse on K-D testing compared to those working full-time (P=0.001, accounting for age). The K-D test, a work disability as well as structural changes as measured by OCT imaging. History of ON and abnormal binocular acuities were associated with worse K-D scores, suggesting that abnormalities detected by K-D may go along with afferent dysfunction in MS patients. A brief test that requires saccadic eye movements, K-D should be considered for future MS trials as

  2. Photovoltaic module mounting system

    Science.gov (United States)

    Miros, Robert H. J. [Fairfax, CA; Mittan, Margaret Birmingham [Oakland, CA; Seery, Martin N [San Rafael, CA; Holland, Rodney H [Novato, CA

    2012-04-17

    A solar array mounting system having unique installation, load distribution, and grounding features, and which is adaptable for mounting solar panels having no external frame. The solar array mounting system includes flexible, pedestal-style feet and structural links connected in a grid formation on the mounting surface. The photovoltaic modules are secured in place via the use of attachment clamps that grip the edge of the typically glass substrate. The panel mounting clamps are then held in place by tilt brackets and/or mid-link brackets that provide fixation for the clamps and align the solar panels at a tilt to the horizontal mounting surface. The tilt brackets are held in place atop the flexible feet and connected link members thus creating a complete mounting structure.

  3. An efficient probe for rapid detection of cyanide in water at parts per billion levels and naked-eye detection of endogenous cyanide.

    Science.gov (United States)

    Kumari, Namita; Jha, Satadru; Bhattacharya, Santanu

    2014-03-01

    A new molecular probe based on an oxidized bis-indolyl skeleton has been developed for rapid and sensitive visual detection of cyanide ions in water and also for the detection of endogenously bound cyanide. The probe allows the "naked-eye" detection of cyanide ions in water with a visual color change from red to yellow (Δλmax =80 nm) with the immediate addition of the probe. It shows high selectivity towards the cyanide ion without any interference from other anions. The detection of cyanide by the probe is ratiometric, thus making the detection quantitative. A Michael-type addition reaction of the probe with the cyanide ion takes place during this chemodosimetric process. In water, the detection limit was found to be at the parts per million level, which improved drastically when a neutral micellar medium was employed, and it showed a parts-per-billion-level detection, which is even 25-fold lower than the permitted limits of cyanide in water. The probe could also efficiently detect the endogenously bound cyanide in cassava (a staple food) with a clear visual color change without requiring any sample pretreatment and/or any special reaction conditions such as pH or temperature. Thus the probe could serve as a practical naked-eye probe for "in-field" experiments without requiring any sophisticated instruments. Copyright © 2014 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

  4. A rapid, naked-eye detection of hypochlorite and bisulfite using a robust and highly-photostable indicator dye Quinaldine Red in aqueous medium

    Science.gov (United States)

    Dutta, Tanoy; Chandra, Falguni; Koner, Apurba L.

    2018-02-01

    A ;naked-eye; detection of health hazardous bisulfite (HSO3-) and hypochlorite (ClO-) using an indicator dye (Quinaldine Red, QR) in a wide range of pH is demonstrated. The molecule contains a quinoline moiety linked to an N,N-dimethylaniline moiety with a conjugated double bond. Treatment of QR with HSO3- and ClO-, in aqueous solution at near-neutral pH, resulted in a colorless product with high selectivity and sensitivity. The detection limit was 47.8 μM and 0.2 μM for HSO3- and ClO- respectively. However, ClO- was 50 times more sensitive and with 2 times faster response compared to HSO3-. The detail characterization and related analysis demonstrate the potential of QR for a rapid, robust and highly efficient colorimetric sensor for the practical applications to detect hypochlorite in water samples.

  5. Contrasting expressions of aggressive behavior released by lesions of the central nucleus of the amygdala during wakefulness and rapid eye movement sleep without atonia in cats.

    Science.gov (United States)

    Zagrodzka, J; Hedberg, C E; Mann, G L; Morrison, A R

    1998-06-01

    Whether damage to the central nucleus of the amygdala (Ace) contributes to the predatorylike attack sometimes observed in rapid eye movement sleep without atonia (REM-A), created in cats by bilateral pontine lesions, was examined. Such lesions eliminate REM sleep skeletal muscle atonia and release elaborate behavior. Unilateral damage to the Ace alone increased affective defensive aggressive behavior toward humans and conspecifics without altering predatory behavior in wakefulness. Pontine lesions added at loci normally not leading to aggression induced predatorylike attacks in REM-A as well as the waking affective defense. Alterations of autonomic activity, the absence of relevant environmental stimuli in REM-A, or both may explain the state-related differences.

  6. Integration of TerraSAR-X, RapidEye and airborne lidar for remote sensing of intertidal bedforms on the upper flats of Norderney (German Wadden Sea)

    Science.gov (United States)

    Adolph, Winny; Jung, Richard; Schmidt, Alena; Ehlers, Manfred; Heipke, Christian; Bartholomä, Alexander; Farke, Hubert

    2017-04-01

    The Wadden Sea is a large coastal transition area adjoining the southern North Sea uniting ecological key functions with an important role in coastal protection. The region is strictly protected by EU directives and national law and is a UNESCO World Heritage Site, requiring frequent quality assessments and regular monitoring. In 2014 an intertidal bedform area characterised by alternating crests and water-covered troughs on the tidal flats of the island of Norderney (German Wadden Sea sector) was chosen to test different remote sensing methods for habitat mapping: airborne lidar, satellite-based radar (TerraSAR-X) and electro-optical sensors (RapidEye). The results revealed that, although sensitive to different surface qualities, all sensors were able to image the bedforms. A digital terrain model generated from the lidar data shows crests and slopes of the bedforms with high geometric accuracy in the centimetre range, but high costs limit the operation area. TerraSAR-X data enabled identifying the positions of the bedforms reflecting the residual water in the troughs also with a high resolution of up to 1.1 m, but with larger footprints and much higher temporal availability. RapidEye data are sensitive to differences in sediment moisture employed to identify crest areas, slopes and troughs, with high spatial coverage but the lowest resolution (6.5 m). Monitoring concepts may differ in their remote sensing requirements regarding areal coverage, spatial and temporal resolution, sensitivity and geometric accuracy. Also financial budgets limit the selection of sensors. Thus, combining differing assets into an integrated concept of remote sensing contributes to solving these issues.

  7. Comparing the Dry Season In-Situ Leaf Area Index (LAI Derived from High-Resolution RapidEye Imagery with MODIS LAI in a Namibian Savanna

    Directory of Open Access Journals (Sweden)

    Manuel J. Mayr

    2015-04-01

    Full Text Available The Leaf Area Index (LAI is one of the most frequently applied measures to characterize vegetation and its dynamics and functions with remote sensing. Satellite missions, such as NASA’s Moderate Resolution Imaging Spectroradiometer (MODIS operationally produce global datasets of LAI. Due to their role as an input to large-scale modeling activities, evaluation and verification of such datasets are of high importance. In this context, savannas appear to be underrepresented with regards to their heterogeneous appearance (e.g., tree/grass-ratio, seasonality. Here, we aim to examine the LAI in a heterogeneous savanna ecosystem located in Namibia’s Owamboland during the dry season. Ground measurements of LAI are used to derive a high-resolution LAI model with RapidEye satellite data. This model is related to the corresponding MODIS LAI/FPAR (Fraction of Absorbed Photosynthetically Active Radiation scene (MOD15A2 in order to evaluate its performance at the intended annual minimum during the dry season. Based on a field survey we first assessed vegetation patterns from species composition and elevation for 109 sites. Secondly, we measured in situ LAI to quantitatively estimate the available vegetation (mean = 0.28. Green LAI samples were then empirically modeled (LAImodel with high resolution RapidEye imagery derived Difference Vegetation Index (DVI using a linear regression (R2 = 0.71. As indicated by several measures of model performance, the comparison with MOD15A2 revealed moderate consistency mostly due to overestimation by the aggregated LAImodel. Model constraints aside, this study may point to important issues for MOD15A2 in savannas concerning the underlying MODIS Land Cover product (MCD12Q1 and a potential adjustment by means of the MODIS Burned Area product (MCD45A1.

  8. A rapid method of ferromanganese nodule mounting

    Digital Repository Service at National Institute of Oceanography (India)

    Mukhopadhyay, S.; Banerjee, R.

    (Fig. 1). Then the mixture in the cast (5) with nodules inside, is kept undisturbed for 30 minutes in sunlight or at room temperature to cure and to allow it to get very hard. Once hardened, the sample can be sawed to the required size by any normal...

  9. Rapid evolution of troglomorphic characters suggests selection rather than neutral mutation as a driver of eye reduction in cave crabs.

    Science.gov (United States)

    Klaus, Sebastian; Mendoza, José C E; Liew, Jia Huan; Plath, Martin; Meier, Rudolf; Yeo, Darren C J

    2013-04-23

    This study asked whether reductive traits in cave organisms evolve at a slower pace (suggesting neutral evolution under relaxed selection) than constructive changes, which are likely to evolve under directional selection. We investigated 11 subterranean and seven surface populations of Sundathelphusa freshwater crabs on Bohol Island, Philippines, and examined constructive traits associated with improved food finding in darkness (increased leg and setae length) and reductive traits (reduced cornea size and eyestalk length). All changes occurred rapidly, given that the age of the most recent common ancestor was estimated to be 722-271 ka based on three mitochondrial markers. In order to quantify the speed of character change, we correlated the degree of morphological change with genetic distances between surface and subterranean individuals. The temporal pattern of character change following the transition to subterranean life was indistinguishable for constructive and reductive traits, characterized by an immediate onset and rapid evolutionary change. We propose that the evolution of these reductive traits-just like constructive traits-is most likely driven by strong directional selection.

  10. Dry eyes : a commonly missed eye condition

    OpenAIRE

    Vella, Mario;

    2014-01-01

    Tears are an important component in providing moisture and lubrication for the eyes, thereby maintaining vision and comfort. Dry eyes (keratoconjunctivitis sicca) result when there is either decreased production of tears or by poor tear quality which in turn lead to more rapid evaporation.

  11. Liner mounting assembly

    Science.gov (United States)

    Halila, Ely E. (Inventor)

    1994-01-01

    A mounting assembly includes an annular supporting flange disposed coaxially about a centerline axis which has a plurality of circumferentially spaced apart supporting holes therethrough. An annular liner is disposed coaxially with the supporting flange and includes a plurality of circumferentially spaced apart mounting holes aligned with respective ones of the supporting holes. Each of a plurality of mounting pins includes a proximal end fixedly joined to the supporting flange through a respective one of the supporting holes, and a distal end disposed through a respective one of the liner mounting holes for supporting the liner to the supporting flange while unrestrained differential thermal movement of the liner relative to the supporting flange.

  12. 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? Leer en Español: ¿Qué son las alergias de ...

  13. Optoelectronic Mounting Structure

    Science.gov (United States)

    Anderson, Gene R.; Armendariz, Marcelino G.; Baca, Johnny R. F.; Bryan, Robert P.; Carson, Richard F.; Chu, Dahwey; Duckett, III, Edwin B.; McCormick, Frederick B.; Peterson, David W.; Peterson, Gary D.; Reber, Cathleen A.; Reysen, Bill H.

    2004-10-05

    An optoelectronic mounting structure is provided that may be used in conjunction with an optical transmitter, receiver or transceiver module. The mounting structure may be a flexible printed circuit board. Thermal vias or heat pipes in the head region may transmit heat from the mounting structure to the heat spreader. The heat spreader may provide mechanical rigidity or stiffness to the heat region. In another embodiment, an electrical contact and ground plane may pass along a surface of the head region so as to provide an electrical contact path to the optoelectronic devices and limit electromagnetic interference. In yet another embodiment, a window may be formed in the head region of the mounting structure so as to provide access to the heat spreader. Optoelectronic devices may be adapted to the heat spreader in such a manner that the devices are accessible through the window in the mounting structure.

  14. Design, Sensing and Control of a Robotic Prosthetic Eye for Natural Eye Movement

    OpenAIRE

    J. J. Gu; M. Meng; A. Cook; P. X. Liu

    2006-01-01

    Loss of an eye is a tragedy for a person, who may suffer psychologically and physically. This paper is concerned with the design, sensing and control of a robotic prosthetic eye that moves horizontally in synchronization with the movement of the natural eye. Two generations of robotic prosthetic eye models have been developed. The first generation model uses an external infrared sensor array mounted on the frame of a pair of eyeglasses to detect the natural eye movement and to feed the contro...

  15. Quantitative assessment of isolated rapid eye movement (REM) sleep without atonia without clinical REM sleep behavior disorder: clinical and research implications.

    Science.gov (United States)

    Sasai-Sakuma, Taeko; Frauscher, Birgit; Mitterling, Thomas; Ehrmann, Laura; Gabelia, David; Brandauer, Elisabeth; Inoue, Yuichi; Poewe, Werner; Högl, Birgit

    2014-09-01

    Rapid eye movement (REM) sleep without atonia (RWA) is observed in some patients without a clinical history of REM sleep behavior disorder (RBD). It remains unknown whether these patients meet the refined quantitative electromyographic (EMG) criteria supporting a clinical RBD diagnosis. We quantitatively evaluated EMG activity and investigated its overnight distribution in patients with isolated qualitative RWA. Fifty participants with an incidental polysomnographic finding of RWA (isolated qualitative RWA) were included. Tonic, phasic, and 'any' EMG activity during REM sleep on PSG were quantified retrospectively. Referring to the quantitative cut-off values for a polysomnographic diagnosis of RBD, 7/50 (14%) and 6/50 (12%) of the patients showed phasic and 'any' EMG activity in the mentalis muscle above the respective cut-off values. No patient was above the cut-off value for tonic EMG activity or phasic EMG activity in the anterior tibialis muscles. Patients with RWA above the cut-off value showed higher amounts of RWA during later REM sleep periods. This is the first study showing that some subjects with incidental RWA meet the refined quantitative EMG criteria for a diagnosis of RBD. Future longitudinal studies must investigate whether this subgroup with isolated qualitative RWA is at an increased risk of developing fully expressed RBD and/or neurodegenerative disease. Copyright © 2014 Elsevier B.V. All rights reserved.

  16. Essential roles of GABA transporter-1 in controlling rapid eye movement sleep and in increased slow wave activity after sleep deprivation.

    Directory of Open Access Journals (Sweden)

    Xin-Hong Xu

    Full Text Available GABA is the major inhibitory neurotransmitter in the mammalian central nervous system that has been strongly implicated in the regulation of sleep. GABA transporter subtype 1 (GAT1 constructs high affinity reuptake sites for GABA and regulates GABAergic transmission in the brain. However, the role of GAT1 in sleep-wake regulation remains elusive. In the current study, we characterized the spontaneous sleep-wake cycle and responses to sleep deprivation in GAT1 knock-out (KO mice. GAT1 KO mice exhibited dominant theta-activity and a remarkable reduction of EEG power in low frequencies across all vigilance stages. Under baseline conditions, spontaneous rapid eye movement (REM sleep of KO mice was elevated both during the light and dark periods, and non-REM (NREM sleep was reduced during the light period only. KO mice also showed more state transitions from NREM to REM sleep and from REM sleep to wakefulness, as well as more number of REM and NREM sleep bouts than WT mice. During the dark period, KO mice exhibited more REM sleep bouts only. Six hours of sleep deprivation induced rebound increases in NREM and REM sleep in both genotypes. However, slow wave activity, the intensity component of NREM sleep was briefly elevated in WT mice but remained completely unchanged in KO mice, compared with their respective baselines. These results indicate that GAT1 plays a critical role in the regulation of REM sleep and homeostasis of NREM sleep.

  17. Abnormal Gray Matter Shape, Thickness, and Volume in the Motor Cortico-Subcortical Loop in Idiopathic Rapid Eye Movement Sleep Behavior Disorder: Association with Clinical and Motor Features.

    Science.gov (United States)

    Rahayel, Shady; Postuma, Ronald B; Montplaisir, Jacques; Bedetti, Christophe; Brambati, Simona; Carrier, Julie; Monchi, Oury; Bourgouin, Pierre-Alexandre; Gaubert, Malo; Gagnon, Jean-François

    2018-02-01

    Idiopathic rapid eye movement sleep behavior disorder (iRBD) is a major risk factor for Parkinson's disease and dementia with Lewy bodies. Anatomical gray matter abnormalities in the motor cortico-subcortical loop areas remain under studied in iRBD patients. We acquired T1-weighted images and administrated quantitative motor tasks in 41 patients with polysomnography-confirmed iRBD and 41 healthy subjects. Cortical thickness and voxel-based morphometry (VBM) analyses were performed to investigate local cortical thickness and gray matter volume changes, vertex-based shape analysis to investigate shape of subcortical structures, and structure-based volumetric analyses to investigate volumes of subcortical and brainstem structures. Cortical thickness analysis revealed thinning in iRBD patients in bilateral medial superior frontal, orbitofrontal, anterior cingulate cortices, and the right dorsolateral primary motor cortex. VBM results showed lower gray matter volume in iRBD patients in the frontal lobes, anterior cingulate gyri, and caudate nucleus. Shape analysis revealed extensive surface contraction in the external and internal segments of the left pallidum. Clinical and motor impaired features in iRBD were associated with anomalies of the motor cortico-subcortical loop. In summary, iRBD patients showed numerous gray matter structural abnormalities in the motor cortico-subcortical loop, which are associated with lower motor performance and clinical manifestations of iRBD. © The Author 2017. Published by Oxford University Press. All rights reserved. For Permissions, please e-mail: journals.permissions@oup.com.

  18. Radiometric Cross-Calibration of the Chilean Satellite FASat-C Using RapidEye and EO-1 Hyperion Data and a Simultaneous Nadir Overpass Approach

    Directory of Open Access Journals (Sweden)

    Carolina Barrientos

    2016-07-01

    Full Text Available The absolute radiometric calibration of a satellite sensor is the critical factor that ensures the usefulness of the acquired data for quantitative applications on remote sensing. This work presents the results of the first cross-calibration of the sensor on board the Sistema Satelital de Observación de la Tierra (SSOT Chilean satellite or Air Force Satellite FASat-C. RapidEye-MSI was chosen as the reference sensor, and a simultaneous Nadir Overpass Approach (SNO was applied. The biases caused by differences in the spectral responses of both instruments were compensated through an adjustment factor derived from EO-1 Hyperion data. Through this method, the variations affecting the radiometric response of New AstroSat Optical Modular Instrument (NAOMI-1, have been corrected based on collections over the Frenchman Flat calibration site. The results of a preliminary evaluation of the pre-flight and updated coefficients have shown a significant improvement in the accuracy of at-sensor radiances and TOA reflectances: an average agreement of 2.63% (RMSE was achieved for the multispectral bands of both instruments. This research will provide a basis for the continuity of calibration and validation tasks of future Chilean space missions.

  19. An improved loopless mounting method for cryocrystallography

    International Nuclear Information System (INIS)

    Jian-Xun, Qi; Fan, Jiang

    2010-01-01

    Based on a recent loopless mounting method, a simplified loopless and bufferless crystal mounting method is developed for macromolecular crystallography. This simplified crystal mounting system is composed of the following components: a home-made glass capillary, a brass seat for holding the glass capillary, a flow regulator, and a vacuum pump for evacuation. Compared with the currently prevalent loop mounting method, this simplified method has almost the same mounting procedure and thus is compatible with the current automated crystal mounting system. The advantages of this method include higher signal-to-noise ratio, more accurate measurement, more rapid flash cooling, less x-ray absorption and thus less radiation damage to the crystal. This method can be extended to the flash-freeing of a crystal without or with soaking it in a lower concentration of cryoprotectant, thus it may be the best option for data collection in the absence of suitable cryoprotectant. Therefore, it is suggested that this mounting method should be further improved and extensively applied to cryocrystallographic experiments. (general)

  20. An improved loopless mounting method for cryocrystallography

    Science.gov (United States)

    Qi, Jian-Xun; Jiang, Fan

    2010-01-01

    Based on a recent loopless mounting method, a simplified loopless and bufferless crystal mounting method is developed for macromolecular crystallography. This simplified crystal mounting system is composed of the following components: a home-made glass capillary, a brass seat for holding the glass capillary, a flow regulator, and a vacuum pump for evacuation. Compared with the currently prevalent loop mounting method, this simplified method has almost the same mounting procedure and thus is compatible with the current automated crystal mounting system. The advantages of this method include higher signal-to-noise ratio, more accurate measurement, more rapid flash cooling, less x-ray absorption and thus less radiation damage to the crystal. This method can be extended to the flash-freeing of a crystal without or with soaking it in a lower concentration of cryoprotectant, thus it may be the best option for data collection in the absence of suitable cryoprotectant. Therefore, it is suggested that this mounting method should be further improved and extensively applied to cryocrystallographic experiments.

  1. Internally Mounting Strain Gages

    Science.gov (United States)

    Jett, J. R., Jr.

    1984-01-01

    Technique for mounting strain gages inside bolt or cylinder simultaneously inserts gage, attached dowel segment, and length of expandable tubing. Expandable tubing holds gage in place while adhesive cures, assuring even distribution of pressure on gage and area gaged.

  2. Mounting for ceramic scroll

    Science.gov (United States)

    Petty, Jack D.

    1993-01-01

    A mounting for a ceramic scroll on a metal engine block of a gas turbine engine includes a first ceramic ring and a pair of cross key connections between the first ceramic ring, the ceramic scroll, and the engine block. The cross key connections support the scroll on the engine block independent of relative radial thermal growth and for bodily movement toward an annular mounting shoulder on the engine. The scroll has an uninterrupted annular shoulder facing the mounting shoulder on the engine block. A second ceramic ring is captured between mounting shoulder and the uninterrupted shoulder on the scroll when the latter is bodily shifted toward the mouting shoulder to define a gas seal between the scroll and the engine block.

  3. Connecting eye to eye

    DEFF Research Database (Denmark)

    Dau, Susanne; Rask, Anders Bindslev

    2017-01-01

    Computer Supported Collaborative Learning (CSCL) is used a frame for supporting online and blended learning in educations. The online communication and collaboration are afforded by the social collaboration. However, the social collaboration is based on the establishment of direct eye contact...... (Khalid, Deska & Hugenberg, 2016), but direct eye contact is challenged by the position of the digital devices and thus CSCL. Lack of eye contact is the chief contributor to the negative effects of online disinhibition (Lapidot-Lefler & Barak, 2012) and the problem is the location of the web camera...... at the computer. Eye contact is challenged by the displacement between the senders´ and receivers´ focus on the screen picture and the camera's location at the top or bottom of screens on all digital devices. The aim of this paper is accordingly to investigate the influence of the displacement in eye contact...

  4. Google Glass Glare: disability glare produced by a head-mounted visual display.

    Science.gov (United States)

    Longley, Chris; Whitaker, David

    2016-03-01

    Head mounted displays are a type of wearable technology - a market that is projected to expand rapidly over the coming years. Probably the most well known example is the device Google Glass (or 'Glass'). Here we investigate the extent to which the device display can interfere with normal visual function by producing monocular disability glare. Contrast sensitivity was measured in two normally sighted participants, 32 and 52 years of age. Data were recorded for the right eye, the left eye and then again in a binocular condition. Measurements were taken both with and without the Glass in place, across a range of stimulus luminance levels using a two-alternative forced-choice methodology. The device produced a significant reduction in contrast sensitivity in the right eye (>0.5 log units). The level of disability glare increased as stimulus luminance was reduced in a manner consistent with intraocular light scatter, resulting in a veiling retinal illuminance. Sensitivity in the left eye was unaffected. A significant reduction in binocular contrast sensitivity occurred at lower luminance levels due to a loss of binocular summation, although binocular sensitivity was not found to fall below the sensitivity of the better monocular level (binocular inhibition). Head mounted displays such as Google Glass have the potential to cause significant disability glare in the eye exposed to the visual display, particularly under conditions of low luminance. They can also cause a more modest binocular reduction in sensitivity by eliminating the benefits of binocular summation. © 2015 The Authors Ophthalmic & Physiological Optics © 2015 The College of Optometrists.

  5. Photovoltaic mounting/demounting unit

    DEFF Research Database (Denmark)

    2014-01-01

    The present invention relates to a photovoltaic arrangement comprising a photovoltaic assembly comprising a support structure defining a mounting surface onto which a photovoltaic module is detachably mounted; and a mounting/demounting unit comprising at least one mounting/demounting apparatus...... which when the mounting/demounting unit is moved along the mounting surface, causes the photovoltaic module to be mounted or demounted to the support structure; wherein the photovoltaic module comprises a carrier foil and wherein a total thickness of the photo voltaic module is below 500 muiotaeta....... The present invention further relates to an associated method for mounting/demounting photovoltaic modules....

  6. Quantification of forest carbon degradation in Nicaragua using RapidEye remote sensing data: El Cuá and Wiwili case studies

    Science.gov (United States)

    Argoty, F. N.; Cifuentes, M.; Imbach, P. A.; Vilchez, S.; Casanoves, F.; Ibrahim, M.; Vierling, L. A.

    2012-12-01

    Forest degradation and deforestation affect ecosystem function and climate regulation services such as carbon storage. Historically, Central America has been a deforestation and forest degradation hotspot. Wiwili and El Cuá municipalities in northern Nicaragua are no exception, where subsistence agriculture and cattle ranch expansion have driven deforestation and other wood extraction activities, leading to various levels of forest degradation. Reduction of Emissions from forest Degradation and Deforestation (REDD) projects are proposed as a tool to slow the degradation and loss of carbon stocks by restoring carbon to its natural levels in order to mitigate carbon dioxide emissions that cause global warming. REDD projects require baseline estimations of current carbon stocks and forest degradation status. We estimated carbon stocks across a forest degradation gradient based on common biophysical variables and commercially available (RapidEye) remote sensing data. We measured 80 temporary forest plots (50x20m) for aboveground biomass to sample a gradient of forest degradation at two municipalities (El Cuá and Wiwili) in northern Nicaragua. We measured biomass in trees (≥10 cm DBH), saplings (5-9.9 cm DBH), other growth forms (ferns, palms and woody vines), and large detritus (snags and downed wood). Biomass was estimated by a range of allometric models and a constant conversion factor (0.47) was applied to calculate aboveground carbon stocks. Remote sensing data from a RapidEye scene for 02/2010 provided data for 5 spectral bands and 19 vegetation indexes at 6 m spatial resolution. Precipitation, temperature, altitude, slope, canopy cover, and aspect were also used as input variables for carbon modeling. We tested linear mixed models, generalized additive mixed models and regression tree approaches to explain carbon stocks based on vegetation indexes and biophysical variables. Additionally, we grouped plots into low (17-168 Mg C ha-1), medium (168-302 Mg C ha-1

  7. The lateral paragigantocellular nucleus modulates parasympathetic cardiac neurons: a mechanism for rapid eye movement sleep-dependent changes in heart rate.

    Science.gov (United States)

    Dergacheva, Olga; Wang, Xin; Lovett-Barr, Mary R; Jameson, Heather; Mendelowitz, David

    2010-08-01

    Rapid eye movement (REM) sleep is generally associated with a withdrawal of parasympathetic activity and heart rate increases; however, episodic vagally mediated heart rate decelerations also occur during REM sleep. This alternating pattern of autonomic activation provides a physiological basis for REM sleep-induced cardiac arrhythmias. Medullary neurons within the lateral paragigantocellular nucleus (LPGi) are thought to be active after REM sleep recovery and play a role in REM sleep control. In proximity to the LPGi are parasympathetic cardiac vagal neurons (CVNs) within the nucleus ambiguus (NA), which are critical for controlling heart rate. This study examined brain stem pathways that may mediate REM sleep-related reductions in parasympathetic cardiac activity. Electrical stimulation of the LPGi evoked inhibitory GABAergic postsynaptic currents in CVNs in an in vitro brain stem slice preparation in rats. Because brain stem cholinergic mechanisms are involved in REM sleep regulation, we also studied the role of nicotinic neurotransmission in modulation of GABAergic pathway from the LGPi to CVNs. Application of nicotine diminished the GABAergic responses evoked by electrical stimulation. This inhibitory effect of nicotine was prevented by the alpha7 nicotinic receptor antagonist alpha-bungarotoxin. Moreover, hypoxia/hypercapnia (H/H) diminished LPGi-evoked GABAergic current in CVNs, and this inhibitory effect was also prevented by alpha-bungarotoxin. In conclusion, stimulation of the LPGi evokes an inhibitory pathway to CVNs, which may constitute a mechanism for the reduced parasympathetic cardiac activity and increase in heart rate during REM sleep. Inhibition of this pathway by nicotinic receptor activation and H/H may play a role in REM sleep-related and apnea-associated bradyarrhythmias.

  8. White and gray matter abnormalities in idiopathic rapid eye movement sleep behavior disorder: a diffusion-tensor imaging and voxel-based morphometry study.

    Science.gov (United States)

    Scherfler, Christoph; Frauscher, Birgit; Schocke, Michael; Iranzo, Alex; Gschliesser, Viola; Seppi, Klaus; Santamaria, Joan; Tolosa, Eduardo; Högl, Birgit; Poewe, Werner

    2011-02-01

    We applied diffusion-tensor imaging (DTI) including measurements of mean diffusivity (MD), a parameter of brain tissue integrity, fractional anisotropy (FA), a parameter of neuronal fiber integrity, as well as voxel-based morphometry (VBM), a measure of gray and white matter volume, to detect brain tissue changes in patients with idiopathic rapid eye movement (REM) sleep behavior disorder (iRBD). Magnetic resonance imaging (MRI) was performed in 26 patients with iRBD (mean disease duration, 9.2 ± 6.4 years) and 14 age-matched healthy control subjects. Statistical parametric mapping (SPM) was applied to objectively identify focal changes of MRI parameters throughout the entire brain volume. SPM localized significant decreases of FA in the tegmentum of the midbrain and rostral pons and increases of MD within the pontine reticular formation overlapping with a cluster of decreased FA in the midbrain (p < 0.001). VBM revealed increases of gray matter densities in both hippocampi of iRBD patients (p < 0.001). The observed changes in the pontomesencephalic brainstem localized 2 areas harboring key neuronal circuits believed to be involved in the regulation of REM sleep and overlap with areas of structural brainstem damage causing symptomatic RBD in humans. Bilateral increases in gray matter density of the hippocampus suggest functional neuronal reorganization in this brain area in iRBD. This study indicates that DTI detects distinct structural brainstem tissue abnormalities in iRBD in the regions where REM is modulated. Further studies should explore the relationship between MRI pathology and the risk of patients with iRBD of developing alpha-synuclein-related neurodegenerative diseases like Parkinson disease. Copyright © 2010 American Neurological Association.

  9. Study on the relation of brain functional connectivity to movement disorders and cognitive impairment in patients with rapid eye movement sleep behavior disorder

    Directory of Open Access Journals (Sweden)

    Hong-ju ZHANG

    2017-09-01

    Full Text Available Objective To explore the relation between abnormal functional connectivity of substantia nigra and impairment of movement and cognition in patients with rapid eye movement sleep behavior disorder (RBD. Methods A total of 22 subjects, including 14 patients with RBD and 8 sex, age, education-matched healthy controls, were enrolled in this study according to international diagnostic criteria. Unified Parkinson's Disease Rating Scale Ⅲ (UPDRS Ⅲ and Hoehn-Yahr Stage were used to evaluate motor function. Digit Ordering Test - Attention (DOT - A, Symbol Digit Modalities Test (SDMT, Stroop Color-Word Test (SCWT, Trail Making Test (TMT, Rey-Osterrieth Complex Figure Test (ROCFT, Clock Drawing Test (CDT, Boston Naming Test (BNT and Auditory Verbal Learning Test (AVLT were used to evaluate cognitive function. The functional connectivity from left and right substantia nigra to brain region were examined. Results There were no statistical differences of UPDRSⅢ and Hoehn?Yahr Stage between 2 groups (P > 0.05, for all. In comparison with control group, SDMT (P = 0.001, ROCFT-copy (P = 0.013 and AVLT-N2 (P = 0.032 were significantly lower, while TMT-B test was significantly higher (P =0.005 in RBD group. Compared with control group, the functional connectivity of right substantia nigra to left precentral gyrus (P < 0.005 and right angular gyrus (P < 0.005 were all decreased in RBD group. Conclusions The results suggest that cognitive impairment occurs earlier than movement disorders in RBD, and there are abnormal functional connectivity from right substantia nigra to left precentral gyrus and right angular gyrus, proving that abnormal functional connectivity is the base of behavior disorders in RBD. DOI: 10.3969/j.issn.1672-6731.2017.09.005

  10. Dreaming furiously? A sleep laboratory study on the dream content of people with Parkinson's disease and with or without rapid eye movement sleep behavior disorder.

    Science.gov (United States)

    Valli, Katja; Frauscher, Birgit; Peltomaa, Taina; Gschliesser, Viola; Revonsuo, Antti; Högl, Birgit

    2015-03-01

    Rapid eye movement (REM) sleep behavior disorder (RBD) has been related to altered, action-filled, vivid, and aggressive dream content, but research comparing the possible differences in dreams of Parkinson's disease (PD) patients with and without RBD is scarce. The dream content of PD patients with and without RBD was analyzed with specific focus on action-filledness, vividness, emotional valence, and threats. A total of 69 REM and NREM dream reports were collected in the sleep laboratory, 37 from nine PD patients with RBD and 32 from six PD patients without RBD. A content analysis of (1) action-filledness (actions and environmental events); (2) vividness (emotions and cognitive activity); (3) intensity of actions, events and emotions; (4) emotional valence, and (5) threatening events was performed on the transcripts. Altogether 563 dream elements expressing action-filledness and vividness were found. There were no significant between-group differences in the number or distribution of elements reflecting action-filledness or vividness, emotional valence or threats. In within-group analyses, PD patients with RBD had significantly more negative compared to positive dreams (p = 0.012) and compared to PD patients without RBD, a tendency to have more intense actions in their dreams (p = 0.066). Based on the results of this study, there are no major between-group differences in the action-filledness, vividness, or threat content of dreams of PD patients with and without RBD. However, within-group analyses revealed that dreams were more often negatively than positively toned in PD patients with RBD. Copyright © 2014 Elsevier B.V. All rights reserved.

  11. The dream-lag effect: Selective processing of personally significant events during Rapid Eye Movement sleep, but not during Slow Wave Sleep.

    Science.gov (United States)

    van Rijn, E; Eichenlaub, J-B; Lewis, P A; Walker, M P; Gaskell, M G; Malinowski, J E; Blagrove, M

    2015-07-01

    Incorporation of details from waking life events into Rapid Eye Movement (REM) sleep dreams has been found to be highest on the night after, and then 5-7 nights after events (termed, respectively, the day-residue and dream-lag effects). In experiment 1, 44 participants kept a daily log for 10 days, reporting major daily activities (MDAs), personally significant events (PSEs), and major concerns (MCs). Dream reports were collected from REM and Slow Wave Sleep (SWS) in the laboratory, or from REM sleep at home. The dream-lag effect was found for the incorporation of PSEs into REM dreams collected at home, but not for MDAs or MCs. No dream-lag effect was found for SWS dreams, or for REM dreams collected in the lab after SWS awakenings earlier in the night. In experiment 2, the 44 participants recorded reports of their spontaneously recalled home dreams over the 10 nights following the instrumental awakenings night, which thus acted as a controlled stimulus with two salience levels, high (sleep lab) and low (home awakenings). The dream-lag effect was found for the incorporation into home dreams of references to the experience of being in the sleep laboratory, but only for participants who had reported concerns beforehand about being in the sleep laboratory. The delayed incorporation of events from daily life into dreams has been proposed to reflect REM sleep-dependent memory consolidation. However, an alternative emotion processing or emotional impact of events account, distinct from memory consolidation, is supported by the finding that SWS dreams do not evidence the dream-lag effect. Copyright © 2015 The Authors. Published by Elsevier Inc. All rights reserved.

  12. Slow oscillating transcranial direct current stimulation during non-rapid eye movement sleep improves behavioral inhibition in attention-deficit/ hyperactivity disorder

    Directory of Open Access Journals (Sweden)

    Manuel Tobias Munz

    2015-08-01

    Full Text Available Background: Behavioral inhibition, which is a later-developing executive function (EF and anatomically located in prefrontal areas, is impaired in attention-deficit and hyperactivity disorder (ADHD. While optimal EFs have been shown to depend on efficient sleep in healthy subjects, the impact of sleep problems, frequently reported in ADHD, remains elusive. Findings of macroscopic sleep changes in ADHD are inconsistent, but there is emerging evidence for distinct microscopic changes with a focus on prefrontal cortical regions and non-rapid eye movement (non-REM slow-wave sleep. Recently, slow oscillations (SO during non-REM sleep were found to be less functional and, as such, may be involved in sleep-dependent memory impairments in ADHD. Objective: By augmenting slow-wave power through bilateral, slow oscillating transcranial direct current stimulation (so-tDCS, frequency = 0.75 Hz during non-REM sleep, we aimed to improve daytime behavioral inhibition in children with ADHD. Methods: 14 boys (10-14 yrs diagnosed with ADHD were included. In a randomized, double-blind, cross-over design, patients received so-tDCS either in the first or in the second experimental sleep night. Inhibition control was assessed with a visuomotor go/no-go task. Intrinsic alertness was assessed with a simple stimulus response task. To control for visuomotor performance, motor memory was assessed with a finger sequence tapping task. Results: SO-power was enhanced during early non-REM sleep, accompanied by slowed reaction times and decreased standard deviations of reaction times, in the go/no-go task after so-tDCS. In contrast, intrinsic alertness and motor memory performance were not improved by so-tDCS. Conclusion: Since behavioral inhibition but not intrinsic alertness or motor memory was improved by so-tDCS, our results suggest that lateral prefrontal slow oscillations during sleep might play a specific role for executive functioning in ADHD.

  13. Blood RNA biomarkers in prodromal PARK4 and rapid eye movement sleep behavior disorder show role of complexin 1 loss for risk of Parkinson's disease

    Directory of Open Access Journals (Sweden)

    Suna Lahut

    2017-05-01

    Full Text Available Parkinson's disease (PD is a frequent neurodegenerative process in old age. Accumulation and aggregation of the lipid-binding SNARE complex component α-synuclein (SNCA underlies this vulnerability and defines stages of disease progression. Determinants of SNCA levels and mechanisms of SNCA neurotoxicity have been intensely investigated. In view of the physiological roles of SNCA in blood to modulate vesicle release, we studied blood samples from a new large pedigree with SNCA gene duplication (PARK4 mutation to identify effects of SNCA gain of function as potential disease biomarkers. Downregulation of complexin 1 (CPLX1 mRNA was correlated with genotype, but the expression of other Parkinson's disease genes was not. In global RNA-seq profiling of blood from presymptomatic PARK4 indviduals, bioinformatics detected significant upregulations for platelet activation, hemostasis, lipoproteins, endocytosis, lysosome, cytokine, Toll-like receptor signaling and extracellular pathways. In PARK4 platelets, stimulus-triggered degranulation was impaired. Strong SPP1, GZMH and PLTP mRNA upregulations were validated in PARK4. When analysing individuals with rapid eye movement sleep behavior disorder, the most specific known prodromal stage of general PD, only blood CPLX1 levels were altered. Validation experiments confirmed an inverse mutual regulation of SNCA and CPLX1 mRNA levels. In the 3′-UTR of the CPLX1 gene we identified a single nucleotide polymorphism that is significantly associated with PD risk. In summary, our data define CPLX1 as a PD risk factor and provide functional insights into the role and regulation of blood SNCA levels. The new blood biomarkers of PARK4 in this Turkish family might become useful for PD prediction.

  14. Effects of Optogenetic inhibition of BLA on Sleep Brief Optogenetic Inhibition of the Basolateral Amygdala in Mice Alters Effects of Stressful Experiences on Rapid Eye Movement Sleep.

    Science.gov (United States)

    Machida, Mayumi; Wellman, Laurie L; Fitzpatrick Bs, Mairen E; Hallum Bs, Olga; Sutton Bs, Amy M; Lonart, György; Sanford, Larry D

    2017-04-01

    Stressful events can directly produce significant alterations in subsequent sleep, in particular rapid eye movement sleep (REM); however, the neural mechanisms underlying the process are not fully known. Here, we investigated the role of the basolateral nuclei of the amygdala (BLA) in regulating the effects of stressful experience on sleep. We used optogenetics to briefly inhibit glutamatergic cells in BLA during the presentation of inescapable footshock (IS) and assessed effects on sleep, the acute stress response, and fear memory. c-Fos expression was also assessed in the amygdala and the medial prefrontal cortex (mPFC), both regions involved in coping with stress, and in brain stem regions implicated in the regulation of REM. Compared to control mice, peri-shock inhibition of BLA attenuated an immediate reduction in REM after IS and produced a significant overall increase in REM. Moreover, upon exposure to the shock context alone, mice receiving peri-shock inhibition of BLA during training showed increased REM without altered freezing (an index of fear memory) or stress-induced hyperthermia (an index of acute stress response). Inhibition of BLA during REM under freely sleeping conditions enhanced REM only when body temperature was high, suggesting the effect was influenced by stress. Peri-shock inhibition of BLA also led to elevated c-Fos expression in the central nucleus of the amygdala and mPFC and differentially altered c-Fos activity in the selected brain stem regions. Glutamatergic cells in BLA can modulate the effects of stress on REM and can mediate effects of fear memory on sleep that can be independent of behavioral fear. © Sleep Research Society 2017. Published by Oxford University Press on behalf of the Sleep Research Society. All rights reserved. For permissions, please e-mail journals.permissions@oup.com.

  15. Binocular Rivalry in Helmet-Mounted Display Applications

    Science.gov (United States)

    1975-06-01

    research apparatus. 31 ., simple magnifying ophthalmic lenses were used, mounted in eyeglass frames. These were 2. 5 diopter lenses for both eyes to...wear eyeglasses with 2. 5 diopter lenses. The focal length of these lenses was 15. 5 inches and the eye waa accommodated at infinity when objects were...HMD luminance is positively related to I-I•D visibility, while ambient scene luminance bears an inverse relation- ship to HMD visibility. Scene

  16. Housing And Mounting Structure

    Science.gov (United States)

    Anderson, Gene R.; Armendariz, Marcelino G.; Baca, Johnny R.F.; Bryan, Robert P.; Carson, Richard F.; Duckett, III, Edwin B.; McCormick, Frederick B.; Miller, Gregory V.; Peterson, David W.; Smith, Terrance T.

    2005-03-08

    This invention relates to an optical transmitter, receiver or transceiver module, and more particularly, to an apparatus for connecting a first optical connector to a second optical connector. The apparatus comprises: (1) a housing having at least a first end and at least a second end, the first end of the housing capable of receiving the first optical connector, and the second end of the housing capable of receiving the second optical connector; (2) a longitudinal cavity extending from the first end of the housing to the second end of the housing; and (3) an electromagnetic shield comprising at least a portion of the housing. This invention also relates to an apparatus for housing a flexible printed circuit board, and this apparatus comprises: (1) a mounting structure having at least a first surface and a second surface; (2) alignment ridges along the first and second surfaces of the mounting structure, the alignment ridges functioning to align and secure a flexible printed circuit board that is wrapped around and attached to the first and second surfaces of the mounting structure; and (3) a series of heat sink ridges adapted to the mounting structure, the heat sink ridges functioning to dissipate heat that is generated from the flexible printed circuit board.

  17. Transducer-Mounting Fixture

    Science.gov (United States)

    Spiegel, Kirk W.

    1990-01-01

    Transducer-mounting fixture holds transducer securely against stud. Projects only slightly beyond stud after installation. Flanged transducer fits into fixture when hinged halves open. When halves reclosed, fixture tightened onto threaded stud until stud makes contact with transducer. Knurled area on fixture aids in tightening fixture on stud.

  18. An Object-Based Image Analysis Method for Monitoring Land Conversion by Artificial Sprawl Use of RapidEye and IRS Data

    Directory of Open Access Journals (Sweden)

    Maud Balestrat

    2012-02-01

    Full Text Available In France, in the peri-urban context, urban sprawl dynamics are particularly strong with huge population growth as well as a land crisis. The increase and spreading of built-up areas from the city centre towards the periphery takes place to the detriment of natural and agricultural spaces. The conversion of land with agricultural potential is all the more worrying as it is usually irreversible. The French Ministry of Agriculture therefore needs reliable and repeatable spatial-temporal methods to locate and quantify loss of land at both local and national scales. The main objective of this study was to design a repeatable method to monitor land conversion characterized by artificial sprawl: (i We used an object-based image analysis to extract artificial areas from satellite images; (ii We built an artificial patch that consists of aggregating all the peripheral areas that characterize artificial areas. The “artificialized” patch concept is an innovative extension of the urban patch concept, but differs in the nature of its components and in the continuity distance applied; (iii The diachronic analysis of artificial patch maps enables characterization of artificial sprawl. The method was applied at the scale of four departments (similar to provinces along the coast of Languedoc-Roussillon, in the South of France, based on two satellite datasets, one acquired in 1996–1997 (Indian Remote Sensing and the other in 2009 (RapidEye. In the four departments, we measured an increase in artificial areas of from 113,000 ha in 1997 to 133,000 ha in 2009, i.e., an 18% increase in 12 years. The package comes in the form of a 1/15,000 valid cartography, usable at the scale of a commune (the smallest territorial division used for administrative purposes in France that can be adapted to departmental and regional scales. The method is reproducible in homogenous spatial-temporal terms, so that it could be used periodically to assess changes in land conversion

  19. Scintillation crystal mounting apparatus

    International Nuclear Information System (INIS)

    Engdahl, L.W.; Deans, A.J.

    1982-01-01

    An improved detector head for a gamma camera is disclosed. The detector head includes a housing and a detector assembly mounted within the housing. Components of the detector assembly include a crystal sub-assembly, a phototube array, and a light pipe between the phototube array and crystal sub-assembly. The invention provides a unique structure for maintaining the phototubes in optical relationship with the light pipe and preventing the application of forces that would cause the camera's crystal to crack

  20. Characterization of Engine Mount Elastomers

    National Research Council Canada - National Science Library

    Szabo, Jeffrey P

    2005-01-01

    As part of a project to develop methods for modelling the performance of engine mounts, several oil resistant alternative materials were prepared, and compared to conventional materials from mounts...

  1. Eye Protection

    OpenAIRE

    Pashby, Tom

    1986-01-01

    Eye injuries frequently occur in the home, at work and at play. Many result in legally blind eyes, and most are preventable. Awareness of potential hazards is essential to preventing eye injuries, particularly in children. In addition, protective devices must be used appropriately. We have developed eye protectors that have proved effective in reducing both the overall incidence and the severity of sports eye injuries.

  2. Design of a head phantom produced on a 3D rapid prototyping printer and comparison with a RANDO and 3M lucite head phantom in eye dosimetry applications.

    Science.gov (United States)

    Homolka, Peter; Figl, Michael; Wartak, Andreas; Glanzer, Mathias; Dünkelmeyer, Martina; Hojreh, Azadeh; Hummel, Johann

    2017-04-21

    An anthropomorphic head phantom including eye inserts allowing placement of TLDs 3 mm below the cornea has been produced on a 3D printer using a photo-cured acrylic resin to best allow tissue equivalence. Thus H p (3) can be determined in radiological and interventional photon radiation fields. Eye doses and doses to the forehead have been compared to an Alderson RANDO head and a 3M Lucite skull phantom in terms of surface dose per incident air kerma for frontal irradiation since the commercial phantoms do not allow placement of TLDs 3 mm below the corneal surface. A comparison of dose reduction factors (DRFs) of a common lead glasses model has also been performed. Eye dose per incident air kerma were comparable between all three phantoms (printed phantom: 1.40, standard error (SE) 0.04; RANDO: 1.36, SE 0.03; 3M: 1.37, SE 0.03). Doses to the forehead were identical to eye surface doses for the printed phantom and the RANDO head (ratio 1.00 SE 0.04, and 0.99 SE 0.03, respectively). In the 3M Lucite skull phantom dose on the forehead was 15% lower than dose to the eyes attributable to phantom properties. DRF of a sport frame style leaded glasses model with 0.75 mm lead equivalence measured were 6.8 SE 0.5, 9.3 SE 0.4 and 10.5 SE 0.5 for the RANDO head, the printed phantom, and the 3M Lucite head phantom, respectively, for frontal irradiation. A comparison of doses measured in 3 mm depth and on the surface of the eyes in the printed phantom revealed no difference larger than standard errors from TLD dosimetry. 3D printing offers an interesting opportunity for phantom design with increasing potential as printers allowing combinations of tissue substitutes will become available. Variations between phantoms may provide a useful indication of uncertainty budgets when using phantom measurements to estimate individual personnel doses.

  3. 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 ... and nerves. If the cancer starts inside the eyeball it's called intraocular cancer. The most common intraocular ...

  4. Black Eye

    Science.gov (United States)

    ... Your Eyes Sep 20, 2017 Eye Injuries from Laundry Packets On the Rise Jun 30, 2017 ... Medical Disclaimer Privacy Policy Terms of Service For Advertisers For Media Ophthalmology Job Center © American ...

  5. 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 ...

  6. Eye Emergencies

    Science.gov (United States)

    ... The Marfan Foundation Marfan & Related Disorders What is Marfan Syndrome? What are Related Disorders? What are the Signs? ... Emergencies Eye Emergencies Lung Emergencies Surgeries Eye Emergencies Marfan syndrome significantly increases your risk of retinal detachment, a ...

  7. Your Eyes

    Science.gov (United States)

    ... away? If you guessed the eye, you're right! Your eyes are at work from the moment you wake up to the ... the eye is seeing. A Muscle Makes It Work The lens is suspended in ... of the lens. That's right — the lens actually changes shape right inside your ...

  8. An Analysis of Eye Movements with Helmet Mounted Displays

    Science.gov (United States)

    2014-03-27

    correct the condition with the attendant risks of loss of the involved ovary, bleeding, infection, or death. d. Menstrual Flow - Prolonged exposures to...vibration could theoretically result in menstrual flow alterations. To date, female subjects at this facility have not reported any unusual problems...ICD Distribution: Original filed with protocol records by PI; copy 1, subjec Appendix C: Testing Checklist 74 An Investigation

  9. Resilient mounting systems in buildings

    NARCIS (Netherlands)

    Breeuwer, R.; Tukker, J.C.

    1976-01-01

    The basic elements of resilient mounting systems are described and various measures for quantifying the effect of such systems defined. Using electrical analogue circuits, the calculation of these measures is illustrated. With special reference to resilient mounting systems in buildings, under

  10. Measuring the eyes of trilobites: a motorized goniometer for macropaleontology

    Energy Technology Data Exchange (ETDEWEB)

    Cowen, R.; Cooper, J.H.

    1985-01-01

    The geometry of the trilobite visual surface is important in studies of trilobite taxonomy, paleoecology, and evolution. Unfortunately, methods for measuring visual surface features have been slow and laborious. The authors have built an apparatus which allows rapid, reliable measurement of angular relationships on the trilobite cephalon. A specimen is mounted on a set of turntables rotated by steeper motors driven by impulses from a computer terminal. As the turntables are rotated, their angular displacements from zero are automatically recorded to a repeatable accuracy of less than half a degree. Thus the angular positions of lens axes, spines, glabella, and other important features can be recorded directly into the computer for further processing and graphics display. The authors apparatus was designed to study the eyes of phacopid-trilobites, for two reasons. First, the Phacops rana group of trilobites is one of the type examples of punctuated speciation. Second, it has been suggested that phacopids had stereoscopic vision in each eye. The new apparatus will allow rapid and accurate study of suites of specimens, in order to test these hypotheses. Their new apparatus, essentially a motorized goniometer, could be used or modified to work with any specimens in which rapid goniometric measurements are useful. Such applications could include routine morphometric studies of molluscan or brachiopod shells or echinoderm tests, as well as specific projects dealing with spines, pores, plates, or septa in a wide variety of fossil invertebrates.

  11. Mount Rainier National Park

    Science.gov (United States)

    Hoffman, Robert; Woodward, Andrea; Haggerty, Patricia K.; Jenkins, Kurt J.; Griffin, Paul C.; Adams, Michael J.; Hagar, Joan; Cummings, Tonnie; Duriscoe, Dan; Kopper, Karen; Riedel, Jon; Samora, Barbara; Marin, Lelaina; Mauger, Guillaume S.; Bumbaco, Karen; Littell, Jeremy S.

    2014-01-01

    Natural Resource Condition Assessments (NRCAs) evaluate current conditions for a subset of natural resources and resource indicators in national parks. NRCAs also report on trends in resource condition (when possible), identify critical data gaps, and characterize a general level of confidence for study findings. The resources and indicators emphasized in a given project depend on the park’s resource setting, status of resource stewardship planning and science in identifying high-priority indicators, and availability of data and expertise to assess current conditions for a variety of potential study resources and indicators. Although the primary objective of NRCAs is to report on current conditions relative to logical forms of reference conditions and values, NRCAs also report on trends, when appropriate (i.e., when the underlying data and methods support such reporting), as well as influences on resource conditions. These influences may include past activities or conditions that provide a helpful context for understanding current conditions and present-day threats and stressors that are best interpreted at park, watershed, or landscape scales (though NRCAs do not report on condition status for land areas and natural resources beyond park boundaries). Intensive cause-andeffect analyses of threats and stressors, and development of detailed treatment options, are outside the scope of NRCAs. It is also important to note that NRCAs do not address resources that lack sufficient data for assessment. For Mount Rainier National Park, this includes most invertebrate species and many other animal species that are subject to significant stressors from climate change and other anthropogenic sources such as air pollutants and recreational use. In addition, we did not include an analysis of the physical hydrology associated with streams (such as riverine landforms, erosion and aggradation which is significant in MORA streams), due to a loss of staff expertise from the USGS

  12. Validation of mobile eye tracking as novel and efficient means for differentiating progressive supranuclear palsy from Parkinson’s disease

    Directory of Open Access Journals (Sweden)

    Svenja eMarx

    2012-12-01

    Full Text Available Background: The decreased ability to carry out vertical saccades is a key symptom of Progressive Supranuclear Palsy (PSP. Objective measurement devices can help to reliably detect subtle eye-movement disturbances to improve sensitivity and specificity of the clinical diagnosis. The present study aims at transferring findings from restricted stationary video-oculography to a wearable head-mounted device, which can be readily applied in clinical practice.Methods: We investigated the eye movements in 10 possible or probable PSP patients, 11 Parkinson’s disease (PD patients and 10 age-matched healthy controls (HC using a mobile, gaze-driven video camera setup (EyeSeeCam. Ocular movements were analyzed during a standardized fixation protocol and in an unrestricted real-life scenario while walking along a corridor.Results: The EyeSeeCam detected prominent impairment of both saccade velocity and amplitude in PSP patients, differentiating them from PD and HCs. Differences were particularly evident for saccades in the vertical plane, and stronger for saccades than for other eye movements. Differences were more pronounced during the standardized protocol than in the real-life scenario. Conclusions: Combined analysis of saccade velocity and saccade amplitude during the fixation protocol with the EyeSeeCam provides a simple, rapid (< 20s and reliable tool to differentiate clinically established PSP patients from PD and HCs. As such, our findings prepare the ground for using wearable eye-tracking in patients with uncertain diagnoses.

  13. Exploring Virtual Worlds With Head-Mounted Displays

    Science.gov (United States)

    Chung, James C.; Harris, Mark R.; Brooks, Frederick P.; Fuchs, Henry; Kelley, Michael T.; Hughes, John W.; Ouh-Young, Ming; Cheung, Clement; Holloway, Richard L.; Pique, Michael

    1989-09-01

    For nearly a decade the University of North Carolina at Chapel Hill has been conducting research in the use of simple head-mounted displays in "real-world" applications. Such units provide the user with non-holographic true three-dimensional information, since the kinetic depth effect, stereoscopy, and other visual cues combine to immerse the user in a "virtual world" which behaves like the real world in some respects. UNC's head-mounted display was built inexpensively from commercially available off-the-shelf components. Tracking of the the user's head position and orientation is performed by a Polhemus Navigation Sciences' 3SPACE* tracker. The host computer uses the tracking information to generate updated images corresponding to the user's new left eye and right eye views. The images are broadcast to two liquid crystal television screens (220x320 pixels) mounted on a horizontal shelf at the user's forehead. The user views these color screens through half-silvered mirrors, enabling the computer-generated image to be superimposed upon the user's real physical environment. The head-mounted display has been incorporated into existing molecular modeling and architectural applications being developed at UNC. In molecular structure studies, chemists are presented with a room-sized molecule with which they can interact in a manner more intuitive than that provided by conventional two-dimensional displays and dial boxes. Walking around and through the large molecule may provide quicker understanding of its structure, and such problems as drug-enzyme docking may be approached with greater insight. In architecture, the head-mounted display enables clients to better appreciate three-dimensional designs, which may be misinterpreted in their conventional two-dimensional form by untrained eyes. The addition of a treadmill to the system provides additional kinesthetic input into the understanding of building size and scale.

  14. 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 ...

  15. Detector Mount Design for IGRINS

    Directory of Open Access Journals (Sweden)

    Jae Sok Oh

    2014-06-01

    Full Text Available The Immersion Grating Infrared Spectrometer (IGRINS is a near-infrared wide-band high-resolution spectrograph jointly developed by the Korea Astronomy and Space Science Institute and the University of Texas at Austin. IGRINS employs three HAWAII-2RG Focal Plane Array (H2RG FPA detectors. We present the design and fabrication of the detector mount for the H2RG detector. The detector mount consists of a detector housing, an ASIC housing, a Field Flattener Lens (FFL mount, and a support base frame. The detector and the ASIC housing should be kept at 65 K and the support base frame at 130 K. Therefore they are thermally isolated by the support made of GFRP material. The detector mount is designed so that it has features of fine adjusting the position of the detector surface in the optical axis and of fine adjusting yaw and pitch angles in order to utilize as an optical system alignment compensator. We optimized the structural stability and thermal characteristics of the mount design using computer-aided 3D modeling and finite element analysis. Based on the structural and thermal analysis, the designed detector mount meets an optical stability tolerance and system thermal requirements. Actual detector mount fabricated based on the design has been installed into the IGRINS cryostat and successfully passed a vacuum test and a cold test.

  16. Rapid Linguistic Ambiguity Resolution in Young Children with Autism Spectrum Disorder: Eye Tracking Evidence for the Limits of Weak Central Coherence.

    Science.gov (United States)

    Hahn, Noemi; Snedeker, Jesse; Rabagliati, Hugh

    2015-12-01

    Individuals with autism spectrum disorders (ASD) have often been reported to have difficulty integrating information into its broader context, which has motivated the Weak Central Coherence theory of ASD. In the linguistic domain, evidence for this difficulty comes from reports of impaired use of linguistic context to resolve ambiguous words. However, recent work has suggested that impaired use of linguistic context may not be characteristic of ASD, and is instead better explained by co-occurring language impairments. Here, we provide a strong test of these claims, using the visual world eye tracking paradigm to examine the online mechanisms by which children with autism resolve linguistic ambiguity. To address concerns about both language impairments and compensatory strategies, we used a sample whose verbal skills were strong and whose average age (7; 6) was lower than previous work on lexical ambiguity resolution in ASD. Participants (40 with autism and 40 controls) heard sentences with ambiguous words in contexts that either strongly supported one reading or were consistent with both (John fed/saw the bat). We measured activation of the unintended meaning through implicit semantic priming of an associate (looks to a depicted baseball glove). Contrary to the predictions of weak central coherence, children with ASD, like controls, quickly used context to resolve ambiguity, selecting appropriate meanings within a second. We discuss how these results constrain the generality of weak central coherence. © 2015 International Society for Autism Research, Wiley Periodicals, Inc.

  17. Intra-and-Inter Species Biomass Prediction in a Plantation Forest: Testing the Utility of High Spatial Resolution Spaceborne Multispectral RapidEye Sensor and Advanced Machine Learning Algorithms

    Directory of Open Access Journals (Sweden)

    Timothy Dube

    2014-08-01

    Full Text Available The quantification of aboveground biomass using remote sensing is critical for better understanding the role of forests in carbon sequestration and for informed sustainable management. Although remote sensing techniques have been proven useful in assessing forest biomass in general, more is required to investigate their capabilities in predicting intra-and-inter species biomass which are mainly characterised by non-linear relationships. In this study, we tested two machine learning algorithms, Stochastic Gradient Boosting (SGB and Random Forest (RF regression trees to predict intra-and-inter species biomass using high resolution RapidEye reflectance bands as well as the derived vegetation indices in a commercial plantation. The results showed that the SGB algorithm yielded the best performance for intra-and-inter species biomass prediction; using all the predictor variables as well as based on the most important selected variables. For example using the most important variables the algorithm produced an R2 of 0.80 and RMSE of 16.93 t·ha−1 for E. grandis; R2 of 0.79, RMSE of 17.27 t·ha−1 for P. taeda and R2 of 0.61, RMSE of 43.39 t·ha−1 for the combined species data sets. Comparatively, RF yielded plausible results only for E. dunii (R2 of 0.79; RMSE of 7.18 t·ha−1. We demonstrated that although the two statistical methods were able to predict biomass accurately, RF produced weaker results as compared to SGB when applied to combined species dataset. The result underscores the relevance of stochastic models in predicting biomass drawn from different species and genera using the new generation high resolution RapidEye sensor with strategically positioned bands.

  18. Mount Oku, Cameroon Volcanic Line

    African Journals Online (AJOL)

    and continental sectors especially for trace elements in basalts. ... continental sector of the trend is a complex .... values higher than those of HIMU but is within ...... (Mount Cameroon, Central Africa): petrogenetic implications. Miner. Petrol.,.

  19. Solar panel parallel mounting configuration

    Science.gov (United States)

    Mutschler, Jr., Edward Charles (Inventor)

    1998-01-01

    A spacecraft includes a plurality of solar panels interconnected with a power coupler and an electrically operated device to provide power to the device when the solar cells are insolated. The solar panels are subject to bending distortion when entering or leaving eclipse. Spacecraft attitude disturbances are reduced by mounting each of the solar panels to an elongated boom made from a material with a low coefficient of thermal expansion, so that the bending of one panel is not communicated to the next. The boom may be insulated to reduce its bending during changes in insolation. A particularly advantageous embodiment mounts each panel to the boom with a single mounting, which may be a hinge. The single mounting prevents transfer of bending moments from the panel to the boom.

  20. Mounting clips for panel installation

    Science.gov (United States)

    Cavieres, Andres; Al-Haddad, Tristan; Goodman, Joseph

    2017-07-11

    A photovoltaic panel mounting clip comprising a base, central indexing tabs, flanges, lateral indexing tabs, and vertical indexing tabs. The mounting clip removably attaches one or more panels to a beam or the like structure, both mechanically and electrically. It provides secure locking of the panels in all directions, while providing guidance in all directions for accurate installation of the panels to the beam or the like structure.

  1. The head-mounted microscope.

    Science.gov (United States)

    Chen, Ting; Dailey, Seth H; Naze, Sawyer A; Jiang, Jack J

    2012-04-01

    Microsurgical equipment has greatly advanced since the inception of the microscope into the operating room. These advancements have allowed for superior surgical precision and better post-operative results. This study focuses on the use of the Leica HM500 head-mounted microscope for the operating phonosurgeon. The head-mounted microscope has an optical zoom from 2× to 9× and provides a working distance from 300 mm to 700 mm. The headpiece, with its articulated eyepieces, adjusts easily to head shape and circumference, and offers a focus function, which is either automatic or manually controlled. We performed five microlaryngoscopic operations utilizing the head-mounted microscope with successful results. By creating a more ergonomically favorable operating posture, a surgeon may be able to obtain greater precision and success in phonomicrosurgery. Phonomicrosurgery requires the precise manipulation of long-handled cantilevered instruments through the narrow bore of a laryngoscope. The head-mounted microscope shortens the working distance compared with a stand microscope, thereby increasing arm stability, which may improve surgical precision. Also, the head-mounted design permits flexibility in head position, enabling operator comfort, and delaying musculoskeletal fatigue. A head-mounted microscope decreases the working distance and provides better ergonomics in laryngoscopic microsurgery. These advances provide the potential to promote precision in phonomicrosurgery. Copyright © 2011 The American Laryngological, Rhinological, and Otological Society, Inc.

  2. Eye Injuries

    Science.gov (United States)

    ... that you could lose your vision. Most eye injuries are preventable. If you play sports or work in certain jobs, you may need protection. The most common type of injury happens when something irritates the ...

  3. Eyes - bulging

    Science.gov (United States)

    ... different ages. In: Lambert SR, Lyons CJ, eds. Taylor and Hoyt's Pediatric Ophthalmology and Strabismus . 5th ed. Philadelphia, PA: Elsevier; 2017:chap 96. Orge FH, Grigorian F. Examination and common problems of the neonatal eye. ...

  4. Evaluation of a remote webcam-based eye tracker

    DEFF Research Database (Denmark)

    Skovsgaard, Henrik; Agustin, Javier San; Johansen, Sune Alstrup

    2011-01-01

    In this paper we assess the performance of an open-source gaze tracker in a remote (i.e. table-mounted) setup, and compare it with two other commercial eye trackers. An experiment with 5 subjects showed the open-source eye tracker to have a significantly higher level of accuracy than one...

  5. What Is Dry Eye?

    Medline Plus

    Full Text Available ... Stories Español Eye Health / Eye Health A-Z Dry Eye Sections What Is Dry Eye? Dry Eye Symptoms ... of Dry Eye Dry Eye Treatment What Is Dry Eye? Leer en Español: ¿Qué es el ojo seco? ...

  6. 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? ...

  7. Solar panel truss mounting systems and methods

    Energy Technology Data Exchange (ETDEWEB)

    Al-Haddad, Tristan Farris; Cavieres, Andres; Gentry, Russell; Goodman, Joseph; Nolan, Wade; Pitelka, Taylor; Rahimzadeh, Keyan; Brooks, Bradley; Lohr, Joshua; Crooks, Ryan; Porges, Jamie; Rubin, Daniel

    2016-06-28

    An exemplary embodiment of the present invention provides a solar panel truss mounting system comprising a base and a truss assembly coupled to the base. The truss assembly comprises a first panel rail mount, second panel rail mount parallel to the first panel rail mount, base rail mount parallel to the first and second panel rail mounts, and a plurality of support members. A first portion of the plurality of support members extends between the first and second panel rail mounts. A second portion of the plurality of support members extends between the first panel rail mount and the base rail mount. A third portion of the plurality of support members extends between the second panel rail mount and the base rail mount. The system can further comprise a plurality of connectors for coupling a plurality of photovoltaic solar panels to the truss assembly.

  8. Solar panel truss mounting systems and methods

    Energy Technology Data Exchange (ETDEWEB)

    Al-Haddad, Tristan Farris; Cavieres, Andres; Gentry, Russell; Goodman, Joseph; Nolan, Wade; Pitelka, Taylor; Rahimzadeh, Keyan; Brooks, Bradley; Lohr, Joshua; Crooks, Ryan; Porges, Jamie; Rubin, Daniel

    2018-01-30

    An exemplary embodiment of the present invention provides a solar panel truss mounting system comprising a base and a truss assembly coupled to the base. The truss assembly comprises a first panel rail mount, second panel rail mount parallel to the first panel rail mount, base rail mount parallel to the first and second panel rail mounts, and a plurality of support members. A first portion of the plurality of support members extends between the first and second panel rail mounts. A second portion of the plurality of support members extends between the first panel rail mount and the base rail mount. A third portion of the plurality of support members extends between the second panel rail mount and the base rail mount. The system can further comprise a plurality of connectors for coupling a plurality of photovoltaic solar panels to the truss assembly.

  9. Solar panel truss mounting systems and methods

    Science.gov (United States)

    Al-Haddad, Tristan Farris; Cavieres, Andres; Gentry, Russell; Goodman, Joseph; Nolan, Wade; Pitelka, Taylor; Rahimzadeh, Keyan; Brooks, Bradley; Lohr, Joshua; Crooks, Ryan; Porges, Jamie; Rubin, Daniel

    2015-10-20

    An exemplary embodiment of the present invention provides a solar panel truss mounting system comprising a base and a truss assembly coupled to the base. The truss assembly comprises a first panel rail mount, second panel rail mount parallel to the first panel rail mount, base rail mount parallel to the first and second panel rail mounts, and a plurality of support members. A first portion of the plurality of support members extends between the first and second panel rail mounts. A second portion of the plurality of support members extends between the first panel rail mount and the base rail mount. A third portion of the plurality of support members extends between the second panel rail mount and the base rail mount. The system can further comprise a plurality of connectors for coupling a plurality of photovoltaic solar panels to the truss assembly.

  10. Eyewear Computing – Augmenting the Human with Head-mounted Wearable Assistants (Dagstuhl Seminar 16042)

    OpenAIRE

    Bulling, Andreas; Cakmakci, Ozan; Kunze, Kai; Rehg, James M.

    2016-01-01

    The seminar was composed of workshops and tutorials on head-mounted eye tracking, egocentric vision, optics, and head-mounted displays. The seminar welcomed 30 academic and industry researchers from Europe, the US, and Asia with a diverse background, including wearable and ubiquitous computing, computer vision, developmental psychology, optics, and human-computer interaction. In contrast to several previous Dagstuhl seminars, we used an ignite talk format to reduce the time of talks to...

  11. Mounting clips for panel installation

    Science.gov (United States)

    Cavieres, Andres; Al-Haddad, Tristan; Goodman, Joseph; Valdes, Francisco

    2017-02-14

    An exemplary mounting clip for removably attaching panels to a supporting structure comprises a base, spring locking clips, a lateral flange, a lever flange, and a spring bonding pad. The spring locking clips extend upwardly from the base. The lateral flange extends upwardly from a first side of the base. The lateral flange comprises a slot having an opening configured to receive at least a portion of one of the one or more panels. The lever flange extends outwardly from the lateral flange. The spring bonding flange extends downwardly from the lever flange. At least a portion of the first spring bonding flange comprises a serrated edge for gouging at least a portion of the one or more panels when the one or more panels are attached to the mounting clip to electrically and mechanically couple the one or more panels to the mounting clip.

  12. A Depth-Based Head-Mounted Visual Display to Aid Navigation in Partially Sighted Individuals

    Science.gov (United States)

    Hicks, Stephen L.; Wilson, Iain; Muhammed, Louwai; Worsfold, John; Downes, Susan M.; Kennard, Christopher

    2013-01-01

    Independent navigation for blind individuals can be extremely difficult due to the inability to recognise and avoid obstacles. Assistive techniques such as white canes, guide dogs, and sensory substitution provide a degree of situational awareness by relying on touch or hearing but as yet there are no techniques that attempt to make use of any residual vision that the individual is likely to retain. Residual vision can restricted to the awareness of the orientation of a light source, and hence any information presented on a wearable display would have to limited and unambiguous. For improved situational awareness, i.e. for the detection of obstacles, displaying the size and position of nearby objects, rather than including finer surface details may be sufficient. To test whether a depth-based display could be used to navigate a small obstacle course, we built a real-time head-mounted display with a depth camera and software to detect the distance to nearby objects. Distance was represented as brightness on a low-resolution display positioned close to the eyes without the benefit focussing optics. A set of sighted participants were monitored as they learned to use this display to navigate the course. All were able to do so, and time and velocity rapidly improved with practise with no increase in the number of collisions. In a second experiment a cohort of severely sight-impaired individuals of varying aetiologies performed a search task using a similar low-resolution head-mounted display. The majority of participants were able to use the display to respond to objects in their central and peripheral fields at a similar rate to sighted controls. We conclude that the skill to use a depth-based display for obstacle avoidance can be rapidly acquired and the simplified nature of the display may appropriate for the development of an aid for sight-impaired individuals. PMID:23844067

  13. A novel rapid genotyping technique for Collie eye anomaly: SYBR Green-based real-time polymerase chain reaction method applicable to blood and saliva specimens on Flinders Technology Associates filter paper.

    Science.gov (United States)

    Chang, Hye-Sook; Mizukami, Keijiro; Yabuki, Akira; Hossain, Mohammad A; Rahman, Mohammad M; Uddin, Mohammad M; Arai, Toshiro; Yamato, Osamu

    2010-09-01

    Collie eye anomaly (CEA) is a canine inherited ocular disease that shows a wide variety of manifestations and severity of clinical lesions. Recently, a CEA-associated mutation was reported, and a DNA test that uses conventional polymerase chain reaction (PCR) has now become available. The objective of the current study was to develop a novel rapid genotyping technique by using SYBR Green-based real-time PCR for future large-scale surveys as a key part in the strategy to eradicate CEA by selective breeding. First, a SYBR Green-based real-time PCR assay for genotyping of CEA was developed and evaluated by using purified DNA samples from normal, carrier, and affected Border Collies in which genotypes had previously been determined by conventional PCR. This real-time PCR assay demonstrated appropriate amplifications in all genotypes, and the results were consistent with those of conventional PCR. Second, the availability of Flinders Technology Associates filter paper (FTA card) as DNA templates for the real-time PCR assay was evaluated by using blood and saliva specimens to determine suitability for CEA screening. DNA-containing solution prepared from a disc of blood- or saliva-spotted FTA cards was available directly as templates for the real-time PCR assay when the volume of solution was 2.5% of the PCR mixture. In conclusion, SYBR Green-based real-time PCR combined with FTA cards is a rapid genotyping technique for CEA that can markedly shorten the overall time required for genotyping as well as simplify the sample preparation. Therefore, this newly developed technique suits large-scale screening in breeding populations of Collie-related breeds.

  14. Design, Sensing and Control of a Robotic Prosthetic Eye for Natural Eye Movement

    Directory of Open Access Journals (Sweden)

    J. J. Gu

    2006-01-01

    Full Text Available Loss of an eye is a tragedy for a person, who may suffer psychologically and physically. This paper is concerned with the design, sensing and control of a robotic prosthetic eye that moves horizontally in synchronization with the movement of the natural eye. Two generations of robotic prosthetic eye models have been developed. The first generation model uses an external infrared sensor array mounted on the frame of a pair of eyeglasses to detect the natural eye movement and to feed the control system to drive the artificial eye to move with the natural eye. The second generation model removes the impractical usage of the eye glass frame and uses the human brain EOG (electro-ocular-graph signal picked up by electrodes placed on the sides of a person's temple to carry out the same eye movement detection and control tasks as mentioned above. Theoretical issues on sensor failure detection and recovery, and signal processing techniques used in sensor data fusion, are studied using statistical methods and artificial neural network based techniques. In addition, practical control system design and implementation using micro-controllers are studied and implemented to carry out the natural eye movement detection and artificial robotic eye control tasks. Simulation and experimental studies are performed, and the results are included to demonstrate the effectiveness of the research project reported in this paper.

  15. Mounting power cables on SOLEIL

    CERN Multimedia

    Laurent Guiraud

    1999-01-01

    The power couplers are mounted on the SOLEIL cryomodule in a clean room. The cryomodule will allow superconducting technology to be used at SOLEIL, the French national synchrotron facility. This work is carried out as part of a collaboration between CERN and CEA Saclay, the French National Atomic Energy Commission.

  16. Shock Mounting for Heavy Machines

    Science.gov (United States)

    Thompson, A. R.

    1984-01-01

    Elastomeric bearings eliminate extraneous forces. Rocket thrust transmitted from motor to load cells via support that absorbs extraneous forces so they do not affect accuracy of thrust measurements. Adapter spoked cone fits over forward end of rocket motor. Shock mounting developed for rocket engines under test used as support for heavy machines, bridges, or towers.

  17. Mount St. Helens aerosol evolution

    Energy Technology Data Exchange (ETDEWEB)

    Oberbeck, V.R.; Farlow, N.H.

    1982-08-01

    Stratospheric aerosol samples were collected using a wire impactor during the year following the eruption of Mount St. Helens. Analysis of samples shows that aerosol volume increased for 6 months due to gas-to-particle conversion and then decreased to background levels in the following 6 months.

  18. Control of Wall Mounting Robot

    DEFF Research Database (Denmark)

    Sloth, Christoffer; Pedersen, Rasmus

    2017-01-01

    This paper presents a method for designing controllers for trajectory tracking with actuator constraints. In particular, we consider a joystick-controlled wall mounting robot called WallMo. In contrast to previous works, a model-free approach is taken to the control problem, where the path...

  19. Eye emergencies

    Science.gov (United States)

    ... eye can be caused by a work-related accident. It can also be caused by common household ... hammers, or other striking tools Working with toxic chemicals Cycling or when in windy and ... A.D.A.M.'s editorial policy , editorial process and privacy policy . A.D.A.M. is ...

  20. Eye Cancer

    Science.gov (United States)

    ... layer of tissue underneath the retina that contains connective tissue and melanocytes, which are pigmented (colored) cells, and nourishes the inside of the eye. The choroid is the most common site for a tumor. Types of intraocular cancer The most common intraocular cancer in adults is ...

  1. Eye trauma

    African Journals Online (AJOL)

    2011-02-02

    Feb 2, 2011 ... Note your findings in an orderly fashion: orbit, lids, conjunctiva, cornea, anterior chamber, iris, pupil reaction, lens, fundus. • Stain cornea with fluorescein. It is advisable to examine the eye as soon as possible since a delay will invariably lead to lid swelling, making the examination far more difficult. This can ...

  2. Mounting of Biomaterials for Use in Ophthalmic Cell Therapies.

    Science.gov (United States)

    Harkin, Damien G; Dunphy, Siobhan E; Shadforth, Audra M A; Dawson, Rebecca A; Walshe, Jennifer; Zakaria, Nadia

    2017-11-01

    When used as scaffolds for cell therapies, biomaterials often present basic handling and logistical problems for scientists and surgeons alike. The quest for an appropriate mounting device for biomaterials is therefore a significant and common problem. In this review, we provide a detailed overview of the factors to consider when choosing an appropriate mounting device including those experienced during cell culture, quality assurance, and surgery. By way of example, we draw upon our combined experience in developing epithelial cell therapies for the treatment of eye diseases. We discuss commercially available options for achieving required goals and provide a detailed analysis of 4 experimental designs developed within our respective laboratories in Australia, the United Kingdom, and Belgium.

  3. Preparation and mounting of adult Drosophila structures in Canada balsam.

    Science.gov (United States)

    Stern, David L; Sucena, Elio

    2012-03-01

    The Drosophila cuticle carries a rich array of morphological details. Thus, cuticle examination has had a central role in the history of genetics. To prepare fine "museum-quality," permanent slides, it is best to mount specimens in Canada Balsam. It is difficult to give precise recipes for Canada Balsam, because every user seems to prefer a slightly different viscosity. Dilute solutions spread easily and do not dry too rapidly while mounting specimens. The disadvantage is that there is actually less Balsam in a "drop" of the solution, and when dried, it can contract from the sides of the coverslip, sometimes disturbing the specimen. Unfortunately, there is no substitute for experience when using Canada Balsam. This protocol describes a procedure for mounting adult cuticles in Canada Balsam.

  4. Solar rotation measurements at Mount Wilson. Pt. 2

    International Nuclear Information System (INIS)

    Labonte, B.J.; Howard, R.; Carnegie Institution of Washington, Pasadena

    1981-01-01

    Possible sources of systematic error in solar Doppler rotational velocities are examined. Scattered light is shown to affect the Mount Wilson solar rotation results, but this effect is not enough to bring the spectroscopic results in coincidence with the sunspot rotation. Interference fringes at the spectrograph focus at Mount Wilson have in two intervals affected the rotation results. It has been possible to correlate this error with temperature and thus correct for it. A misalignment between the entrance and exit slits is a possible source of error, but for the Mount Wilson slit configuration the amplitude of this effect is negligibly small. Rapid scanning of the solar image also produces no measurable effect. (orig.)

  5. Diabetic Eye Disease

    Science.gov (United States)

    ... Disease, & Other Dental Problems Diabetes & Sexual & Urologic Problems Diabetic Eye Disease What is diabetic eye disease? Diabetic eye disease is a group ... eye diseases that can threaten your sight are Diabetic retinopathy The retina is the inner lining at ...

  6. 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- ...

  7. 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 "crossed eyes" or "walleye." Nystagmus - fast, uncontrollable movements of the eyes, sometimes called "dancing eyes" Some ...

  8. About the Eye

    Medline Plus

    Full Text Available ... for Kids >> About the Eye Listen All About Vision About the Eye Ask a Scientist Video Series ... Eye Health and Safety First Aid Tips Healthy Vision Tips Protective Eyewear Sports and Your Eyes Fun ...

  9. Why Do Eyes Water?

    Science.gov (United States)

    ... for Educators Search English Español Why Do Eyes Water? KidsHealth / For Kids / Why Do Eyes Water? What's ... coming out of your nose. Why Do Eyes Water? Eyes water for lots of different reasons besides ...

  10. Tension pneumocephalus: Mount Fuji sign

    Directory of Open Access Journals (Sweden)

    Pulastya Sanyal

    2015-01-01

    Full Text Available A 13-year-old male was operated for a space occupying lesion in the brain. A noncontrast computed tomography scan done in the late postoperative period showed massive subdural air collection causing compression of bilateral frontal lobes with widening of interhemispheric fissure and the frontal lobes acquiring a peak like configuration - causing tension pneumocephalus-"Mount Fuji sign." Tension pneumocephalus occurs when air enters the extradural or intradural spaces in sufficient volume to exert a mass or pressure effect on the brain, leading to brain herniation. Tension pneumocephalus is a surgical emergency, which needs immediate intervention in the form of decompression of the cranial cavity by a burr hole or needle aspiration. The Mount Fuji sign differentiates tension pneumocephalus from pneumocephalus.

  11. What Is Dry Eye?

    Medline Plus

    Full Text Available ... Eye Health A-Z Symptoms Glasses & Contacts Tips & Prevention News Ask an Ophthalmologist Patient Stories Español Eye ... Eye Symptoms Causes of Dry Eye Dry Eye Treatment What Is Dry Eye? Leer en Español: ¿Qué ...

  12. What Is Dry Eye?

    Medline Plus

    Full Text Available ... Eye? Dry Eye Symptoms Causes of Dry Eye Dry Eye Treatment What Is Dry Eye? Leer en Español: ¿Qué ... Inside of Your Eyelid Nov 29, 2017 New Dry Eye Treatment is a Tear-Jerker Jul 21, 2017 Three ...

  13. What Is Dry Eye?

    Science.gov (United States)

    ... Eye? Dry Eye Symptoms Causes of Dry Eye Dry Eye Treatment What Is Dry Eye? Leer en Español: ¿Qué ... Inside of Your Eyelid Nov 29, 2017 New Dry Eye Treatment is a Tear-Jerker Jul 21, 2017 Three ...

  14. Mounting support for a photovoltaic module

    Science.gov (United States)

    Brandt, Gregory Michael; Barsun, Stephan K.; Coleman, Nathaniel T.; Zhou, Yin

    2013-03-26

    A mounting support for a photovoltaic module is described. The mounting support includes a foundation having an integrated wire-way ledge portion. A photovoltaic module support mechanism is coupled with the foundation.

  15. Searching for the prototypic eye genetic network: Sine oculis is essential for eye regeneration in planarians

    Science.gov (United States)

    Pineda, D.; Gonzalez, J.; Callaerts, P.; Ikeo, K.; Gehring, W. J.; Salo, E.

    2000-01-01

    We have identified a sine oculis gene in the planarian Girardia tigrina (Platyhelminthes; Turbellaria; Tricladida). The planarian sine oculis gene (Gtso) encodes a protein with a sine oculis (Six) domain and a homeodomain that shares significant sequence similarity with so proteins assigned to the Six-2 gene family. Gtso is expressed as a single transcript in both regenerating and fully developed eyes. Whole-mount in situ hybridization studies show exclusive expression in photoreceptor cells. Loss of function of Gtso by RNA interference during planarian regeneration inhibits eye regeneration completely. Gtso is also essential for maintenance of the differentiated state of photoreceptor cells. These results, combined with the previously demonstrated expression of Pax-6 in planarian eyes, suggest that the same basic gene regulatory circuit required for eye development in Drosophila and mouse is used in the prototypic eye spots of platyhelminthes and, therefore, is truly conserved during evolution. PMID:10781056

  16. Flush Mounting Of Thin-Film Sensors

    Science.gov (United States)

    Moore, Thomas C., Sr.

    1992-01-01

    Technique developed for mounting thin-film sensors flush with surfaces like aerodynamic surfaces of aircraft, which often have compound curvatures. Sensor mounted in recess by use of vacuum pad and materials selected for specific application. Technique involves use of materials tailored to thermal properties of substrate in which sensor mounted. Together with customized materials, enables flush mounting of thin-film sensors in most situations in which recesses for sensors provided. Useful in both aircraft and automotive industries.

  17. Mounting Thin Samples For Electrical Measurements

    Science.gov (United States)

    Matus, L. G.; Summers, R. L.

    1988-01-01

    New method for mounting thin sample for electrical measurements involves use of vacuum chuck to hold a ceramic mounting plate, which holds sample. Contacts on mounting plate establish electrical connection to sample. Used to make electrical measurements over temperature range from 77 to 1,000 K and does not introduce distortions into magnetic field during Hall measurements.

  18. Communication Aid with Human Eyes Only

    Science.gov (United States)

    Arai, Kohei; Yajima, Kenro

    A communication aid with human eyes only is proposed. A set of candidate character is displayed onto computer screen of relatively small and light Head Mount Display: HMD that is mounted on glasses of which user wears on. When user looks at a candidate character with his/hers left eye while right eye picture is taken with small and light web camera that also is mounted on the glasses. The proposed system can selects 81 characters with two layers of 9 by 9 character candidate image. Other than these there is another selective image including control keys and frequently use of sentences. By using image matching between previously acquired template image for each candidate character and the currently acquired image, the proposed system realizes that which character in the candidates is selected. By using blinking and fix one's eye on combine together, the proposed system recognizes that user determines the selected key from the candidates. The blinking detection method employs a morphologic filter to avoid misunderstanding of dark eye detection due to eyebrows and shadows. Thus user can input sentences. User also may edit the sentences and then the sentences are read with Text to Speech: TTS software tool. Thus the system allows support conversations between handicapped and disabled persons without voice and the others peoples because only the function required for conversation is human eyes. Also the proposed system can be used as an input system for wearable computing systems. Test results by the 6 different able persons show that the proposed system does work with acceptable speed, around 1.5 second / character.

  19. 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.

  20. Passive method of eliminating accommodation/convergence disparity in stereoscopic head-mounted displays

    Science.gov (United States)

    Eichenlaub, Jesse B.

    2005-03-01

    The difference in accommodation and convergence distance experienced when viewing stereoscopic displays has long been recognized as a source of visual discomfort. It is especially problematic in head mounted virtual reality and enhanced reality displays, where images must often be displayed across a large depth range or superimposed on real objects. DTI has demonstrated a novel method of creating stereoscopic images in which the focus and fixation distances are closely matched for all parts of the scene from close distances to infinity. The method is passive in the sense that it does not rely on eye tracking, moving parts, variable focus optics, vibrating optics, or feedback loops. The method uses a rapidly changing illumination pattern in combination with a high speed microdisplay to create cones of light that converge at different distances to form the voxels of a high resolution space filling image. A bench model display was built and a series of visual tests were performed in order to demonstrate the concept and investigate both its capabilities and limitations. Results proved conclusively that real optical images were being formed and that observers had to change their focus to read text or see objects at different distances

  1. What Is Dry Eye?

    Medline Plus

    Full Text Available ... Tips & Prevention News Ask an Ophthalmologist Patient Stories Español Eye Health / Eye Health A-Z Dry Eye ... Eye Treatment What Is Dry Eye? Leer en Español: ¿Qué es el ojo seco? Written By: Kierstan ...

  2. What Is Dry Eye?

    Medline Plus

    Full Text Available ... Eye Symptoms Causes of Dry Eye Dry Eye Treatment What Is Dry Eye? Leer en Español: ¿Qué ... Your Eyelid Nov 29, 2017 New Dry Eye Treatment is a Tear-Jerker Jul 21, 2017 Three ...

  3. Bags Under Eyes

    Science.gov (United States)

    Bags under eyes Overview Bags under eyes — mild swelling or puffiness under the eyes — are common as you age. With aging, the tissues around your ... space below your eyes, adding to the swelling. Bags under eyes are usually a cosmetic concern and ...

  4. About the Eye

    Medline Plus

    Full Text Available ... Ask a Scientist Video Series Glossary The Visual System Your Eyes’ Natural Defenses Eye Health and Safety First Aid Tips Healthy Vision Tips Protective Eyewear Sports and Your Eyes Fun Stuff Cool Eye Tricks Links to More Information Optical Illusions Printables About the Eye Your eyes ...

  5. Rapid Eye Movement Sleep, Sleep Continuity and Slow Wave Sleep as Predictors of Cognition, Mood, and Subjective Sleep Quality in Healthy Men and Women, Aged 20–84 Years

    Directory of Open Access Journals (Sweden)

    Ciro della Monica

    2018-06-01

    Full Text Available Sleep and its sub-states are assumed to be important for brain function across the lifespan but which aspects of sleep associate with various aspects of cognition, mood and self-reported sleep quality has not yet been established in detail. Sleep was quantified by polysomnography, quantitative Electroencephalogram (EEG analysis and self-report in 206 healthy men and women, aged 20–84 years, without sleep complaints. Waking brain function was quantified by five assessments scheduled across the day covering objectively assessed performance across cognitive domains including sustained attention and arousal, decision and response time, motor and sequence control, working memory, and executive function as well as self-reports of alertness, mood and affect. Controlled for age and sex, self-reported sleep quality was negatively associated with number of awakenings and positively associated with the duration of Rapid Eye Movement (REM sleep, but no significant associations with Slow Wave Sleep (SWS measures were observed. Controlling only for age showed that associations between objective and subjective sleep quality were much stronger in women than in men. Analysis of 51 performance measures demonstrated that, after controlling for age and sex, fewer awakenings and more REM sleep were associated significantly with better performance on the Goal Neglect task, which is a test of executive function. Factor analysis of the individual performance measures identified four latent variables labeled Mood/Arousal, Response Time, Accuracy, and Visual Perceptual Sensitivity. Whereas Mood/Arousal improved with age, Response Times became slower, while Accuracy and Visual perceptual sensitivity showed little change with age. After controlling for sex and age, nominally significant association between sleep and factor scores were observed such that Response Times were faster with more SWS, and Accuracy was reduced where individuals woke more often or had less REM

  6. EyeAR: Refocusable Augmented Reality Content through Eye Measurements

    Directory of Open Access Journals (Sweden)

    Damien Constantine Rompapas

    2017-09-01

    Full Text Available Augmented Reality (AR superimposes computer graphics (CG onto a user’s view of the real world. A key quality problem in this field is to achieve coherence between reality and CG when the user’s eyes refocus or change pupil size. We designed and evaluated a display that improves coherence by measuring the user’s eye state and continuously adapting CG accordingly. Our tabletop prototype emulates an Optical See-Through Head-Mounted Display, a common AR display device. In our evaluation, participants observed three pillars at different depths. We then challenged them to identify a virtual pillar among the three while freely refocusing their eyes. Results show that our design significantly improved realism. Compared to Light Field Displays, our design aims to simplify display-optics while providing similar quality. We could only partially achieve this goal. We discuss the lessons we learned and how we plan to overcome the remaining challenges. The experimental protocol from our evaluation is useful for display developers as it can be used to measure the coherence of a display.

  7. Rapid world modeling

    International Nuclear Information System (INIS)

    Little, Charles; Jensen, Ken

    2002-01-01

    Sandia National Laboratories has designed and developed systems capable of large-scale, three-dimensional mapping of unstructured environments in near real time. This mapping technique is called rapid world modeling and has proven invaluable when used by prototype systems consisting of sensory detection devices mounted on mobile platforms. These systems can be deployed into previously unmapped environments and transmit real-time 3-D visual images to operators located remotely. This paper covers a brief history of the rapid world modeling system, its implementation on mobile platforms, and the current state of the technology. Applications to the nuclear power industry are discussed. (author)

  8. About the Eye

    Medline Plus

    Full Text Available ... your eye. It helps your eye focus light so things look sharp and clear. Sclera (SKLEH-ruh) ... the different parts of your eye work together so you can see and make sense of the ...

  9. About the Eye

    Medline Plus

    Full Text Available ... Glossary The Visual System Your Eyes’ Natural Defenses Eye Health and Safety First Aid Tips Healthy Vision ... to More Information Optical Illusions Printables About the Eye Your eyes are made up of many different ...

  10. Fluorescein eye stain

    Science.gov (United States)

    Abnormal results may point to: Abnormal tear production (dry eye) Blocked tear duct Corneal abrasion (a scratch on ... object in eye ) Infection Injury or trauma Severe dry eye associated with arthritis (keratoconjunctivitis sicca)

  11. What Is Dry Eye?

    Medline Plus

    Full Text Available ... Member Services Advocacy Foundation About Subspecialties & More Eye Health Home Annual Meeting Clinical Education Practice Management Member ... Center Redmond Ethics Center Global Ophthalmology Guide Eye Health Find an Ophthalmologist Academy Store Eye Health A- ...

  12. What Is Dry Eye?

    Medline Plus

    Full Text Available ... Ophthalmology/Strabismus Ocular Pathology/Oncology Oculoplastics/Orbit Refractive Management/Intervention Retina/Vitreous Uveitis Focus On ... Dry Eye Sections What Is Dry Eye? Dry Eye Symptoms Causes of ...

  13. What Is Dry Eye?

    Medline Plus

    Full Text Available ... Dry Eye Symptoms Related Ask an Ophthalmologist Answers Can a six-month dissolvable punctal plug be removed ... my eyes dry after LASIK? Jun 19, 2016 Can I be tested whether I close my eyes ...

  14. Eye Injuries at Work

    Science.gov (United States)

    ... National Standards Institute (ANSI) to meet their eye protection standards. If an eye injury occurs, see an ophthalmologist or go to the emergency room immediately, even if the eye injury appears minor. Delaying medical attention can result in permanent vision ...

  15. EyeGENE

    Data.gov (United States)

    U.S. Department of Health & Human Services — The eyeGENE® Biorepository and corresponding Database contain family history and clinical eye exam data from subjects enrolled in eyeGENE® Program coupled to...

  16. Ocean floor mounting of wave energy converters

    Science.gov (United States)

    Siegel, Stefan G

    2015-01-20

    A system for mounting a set of wave energy converters in the ocean includes a pole attached to a floor of an ocean and a slider mounted on the pole in a manner that permits the slider to move vertically along the pole and rotate about the pole. The wave energy converters can then be mounted on the slider to allow adjustment of the depth and orientation of the wave energy converters.

  17. Mounting and Alignment of IXO Mirror Segments

    Science.gov (United States)

    Chan, Kai-Wing; Zhang, William; Evans, Tyler; McClelland, Ryan; Hong, Melinda; Mazzarella, James; Saha, Timo; Jalota, Lalit; Olsen, Lawrence; Byron, Glenn

    2010-01-01

    A suspension-mounting scheme is developed for the IXO (International X-ray Observatory) mirror segments in which the figure of the mirror segment is preserved in each stage of mounting. The mirror, first fixed on a thermally compatible strongback, is subsequently transported, aligned and transferred onto its mirror housing. In this paper, we shall outline the requirement, approaches, and recent progress of the suspension mount processes.

  18. Recent advances in head-mounted light field displays for virtual and augmented reality (Conference Presentation)

    Science.gov (United States)

    Hua, Hong

    2017-02-01

    Head-mounted light field displays render a true 3D scene by sampling either the projections of the 3D scene at different depths or the directions of the light rays apparently emitted by the 3D scene and viewed from different eye positions. They are capable of rendering correct or nearly correct focus cues and addressing the very well-known vergence-accommodation mismatch problem in conventional virtual and augmented reality displays. In this talk, I will focus on reviewing recent advancements of head-mounted light field displays for VR and AR applications. I will demonstrate examples of HMD systems developed in my group.

  19. Development of a helmet-mounted PLZT thermal/flash protection system

    International Nuclear Information System (INIS)

    Harris, J.O. Jr.; Cutchen, J.T.; Pfoff, B.J.

    1976-01-01

    Sandia Laboratories is developing PLZT thermal/flash protective devices (TFPD's) goggles to prevent exposure and resultant eye damage from nuclear weapon detonations. The primary emphasis of the present program is to transfer technology and establish production capability for helmet-mounted PLZT/TFPD goggles for USAF flight crews, with a non-helmet-mounted configuration to follow. The first production units are anticipated in the fall of 1977. The operating principles of the PLZT/TFPD goggle device are briefly outlined, and the device configuration and operational characteristics are described

  20. Channel uranium-graphite reactor mounting

    International Nuclear Information System (INIS)

    Polushkin, K.K.; Kuznetsov, A.G.; Zheleznyakov, B.N.

    1981-01-01

    According to theoretical principles of general engineering technology the engineering experience of construction-mounting works at the NPP with channel uranium-graphite reactors is systematized. Main parameters and structural features of the 1000 MW channel uranium-graphite reactors are considered. The succession of mounting operations, premounting equipment and pipelines preparation and mounting works technique are described. The most efficient methods of fitting, welding and machining of reactor elements are recommended. Main problems of technical control service are discussed. A typical netted diagram of main equipment of channel uranium-graphite reactors mounting is given

  1. Amblyopia treatment of adults with dichoptic training using the virtual reality oculus rift head mounted display: preliminary results

    OpenAIRE

    Žiak, Peter; Holm, Anders; Halička, Juraj; Mojzis, Peter; Piñero, David P.

    2017-01-01

    Background The gold standard treatments in amblyopia are penalizing therapies, such as patching or blurring vision with atropine that are aimed at forcing the use of the amblyopic eye. However, in the last years, new therapies are being developed and validated, such as dichoptic visual training, aimed at stimulating the amblyopic eye and eliminating the interocular supression. Purpose To evaluate the effect of dichoptic visual training using a virtual reality head mounted display in a sample ...

  2. The auriferous placer at Mount Robert, Pietersburg Greenstone belt

    International Nuclear Information System (INIS)

    Saager, R.; Muff, R.

    1986-01-01

    The Mount Robert gold placer near Potgietersrus occurs in coarse, matrix-supported conglomerates of the Uitkyk Formation within the Pietersburg greenstone belt. Sedimentological and mineralogical investigations indicate that the conglomerates and the ore minerals were derived from a greenstone provenance, and that they were deposited in a braided river environment within a rapidly subsiding trough. Lack of sedimentological concentration of the heavy minerals is considered to be the main reason for the low and erratic gold grades encountered (usually below 1 g/t) and, thus, the failure of all past mining ventures. The mineralogical composition of the Mount Robert ore closely resembles that of the Witwatersrand deposits. However, uraninite is absent, probably as a result of its complete removal by weathering processes. Remaining small uranium concentrations can still be detected within the conglomerates where they occur associated with grains of carbonaceous matter, leucoxene aggregates, and secondary iron-hydroxides. U3O8 values found in the conglomerates are given

  3. Geologic Map of Mount Mazama and Crater Lake Caldera, Oregon

    Science.gov (United States)

    Bacon, Charles R.

    2008-01-01

    Crater Lake partly fills one of the most spectacular calderas of the world, an 8-by-10-km basin more than 1 km deep formed by collapse of the volcano known as Mount Mazama (fig. 1) during a rapid series of explosive eruptions about 7,700 years ago. Having a maximum depth of 594 m, Crater Lake is the deepest lake in the United States. Crater Lake National Park, dedicated in 1902, encompasses 645 km2 of pristine forested and alpine terrain, including the lake itself, virtually all of Mount Mazama, and most of the area of the geologic map. The geology of the area was first described in detail by Diller and Patton (1902) and later by Williams (1942), whose vivid account led to international recognition of Crater Lake as the classic collapse caldera. Because of excellent preservation and access, Mount Mazama, Crater Lake caldera, and the deposits formed by the climactic eruption constitute a natural laboratory for study of volcanic and magmatic processes. For example, the climactic ejecta are renowned among volcanologists as evidence for systematic compositional zonation within a subterranean magma chamber. Mount Mazama's climactic eruption also is important as the source of the widespread Mazama ash, a useful Holocene stratigraphic marker throughout the Pacific Northwest, adjacent Canada, and offshore. A detailed bathymetric survey of the floor of Crater Lake in 2000 (Bacon and others, 2002) provides a unique record of postcaldera eruptions, the interplay between volcanism and filling of the lake, and sediment transport within this closed basin. Knowledge of the geology and eruptive history of the Mount Mazama edifice, greatly enhanced by the caldera wall exposures, gives exceptional insight into how large volcanoes of magmatic arcs grow and evolve. Lastly, the many smaller volcanoes of the High Cascades beyond the limits of Mount Mazama are a source of information on the flux of mantle-derived magma through the region. General principles of magmatic and eruptive

  4. Head-Mounted Display Technology for Low Vision Rehabilitation and Vision Enhancement

    Science.gov (United States)

    Ehrlich, Joshua R.; Ojeda, Lauro V.; Wicker, Donna; Day, Sherry; Howson, Ashley; Lakshminarayanan, Vasudevan; Moroi, Sayoko E.

    2017-01-01

    Purpose To describe the various types of head-mounted display technology, their optical and human factors considerations, and their potential for use in low vision rehabilitation and vision enhancement. Design Expert perspective. Methods An overview of head-mounted display technology by an interdisciplinary team of experts drawing on key literature in the field. Results Head-mounted display technologies can be classified based on their display type and optical design. See-through displays such as retinal projection devices have the greatest potential for use as low vision aids. Devices vary by their relationship to the user’s eyes, field of view, illumination, resolution, color, stereopsis, effect on head motion and user interface. These optical and human factors considerations are important when selecting head-mounted displays for specific applications and patient groups. Conclusions Head-mounted display technologies may offer advantages over conventional low vision aids. Future research should compare head-mounted displays to commonly prescribed low vision aids in order to compare their effectiveness in addressing the impairments and rehabilitation goals of diverse patient populations. PMID:28048975

  5. 49 CFR 179.10 - Tank mounting.

    Science.gov (United States)

    2010-10-01

    ... 49 Transportation 2 2010-10-01 2010-10-01 false Tank mounting. 179.10 Section 179.10 Transportation Other Regulations Relating to Transportation PIPELINE AND HAZARDOUS MATERIALS SAFETY... Design Requirements § 179.10 Tank mounting. (a) The manner in which tanks are attached to the car...

  6. Low-Thermal-Resistance Baseplate Mounting

    Science.gov (United States)

    Perreault, W. T.

    1984-01-01

    Low-thermal-resistance mounting achieved by preloading baseplate to slight convexity with screws threaded through beam. As mounting bolts around edge of base-place tightened, baseplate and cold plate contact first in center, with region of intimate contact spreading outward as bolts tightened.

  7. Mount Athos: Between autonomy and statehood

    Directory of Open Access Journals (Sweden)

    Avramović Dragutin

    2013-01-01

    Full Text Available Legal status of the Mount Athos is characterized by many special features that make it internationally unique legal regime. The author analyzes peculiarities of Mount Athos territorial status, legal position of residents and visitors, as well as organization of Mount Athos authorities. The author concludes that the Mount Athos is characterized by a kind of para-sovereignty. Its autonomy involves not only the internal organization, autonomous governance and religious autonomy, but it also includes many elements of secular life of their visitors. Mount Athos has its own, separate legislative, administrative and judicial powers, while the Statute of the Mount Athos has greater legal force than all the other laws of the Greek state, because the state can not unilaterally change its provisions. Having in mind that the wide self-government is vested in church authorities and that the monks have very specific way of living, the author takes a position that the Mount Athos represent 'monastic state', but without statehood. The author also states that the Mount Athos will be faced with many challenges in the context of spreading of an assimilating, universal conception of human rights.

  8. Maxwellian Eye Fixation during Natural Scene Perception

    Directory of Open Access Journals (Sweden)

    Jean Duchesne

    2012-01-01

    Full Text Available When we explore a visual scene, our eyes make saccades to jump rapidly from one area to another and fixate regions of interest to extract useful information. While the role of fixation eye movements in vision has been widely studied, their random nature has been a hitherto neglected issue. Here we conducted two experiments to examine the Maxwellian nature of eye movements during fixation. In Experiment 1, eight participants were asked to perform free viewing of natural scenes displayed on a computer screen while their eye movements were recorded. For each participant, the probability density function (PDF of eye movement amplitude during fixation obeyed the law established by Maxwell for describing molecule velocity in gas. Only the mean amplitude of eye movements varied with expertise, which was lower in experts than novice participants. In Experiment 2, two participants underwent fixed time, free viewing of natural scenes and of their scrambled version while their eye movements were recorded. Again, the PDF of eye movement amplitude during fixation obeyed Maxwell’s law for each participant and for each scene condition (normal or scrambled. The results suggest that eye fixation during natural scene perception describes a random motion regardless of top-down or of bottom-up processes.

  9. Maxwellian Eye Fixation during Natural Scene Perception

    Science.gov (United States)

    Duchesne, Jean; Bouvier, Vincent; Guillemé, Julien; Coubard, Olivier A.

    2012-01-01

    When we explore a visual scene, our eyes make saccades to jump rapidly from one area to another and fixate regions of interest to extract useful information. While the role of fixation eye movements in vision has been widely studied, their random nature has been a hitherto neglected issue. Here we conducted two experiments to examine the Maxwellian nature of eye movements during fixation. In Experiment 1, eight participants were asked to perform free viewing of natural scenes displayed on a computer screen while their eye movements were recorded. For each participant, the probability density function (PDF) of eye movement amplitude during fixation obeyed the law established by Maxwell for describing molecule velocity in gas. Only the mean amplitude of eye movements varied with expertise, which was lower in experts than novice participants. In Experiment 2, two participants underwent fixed time, free viewing of natural scenes and of their scrambled version while their eye movements were recorded. Again, the PDF of eye movement amplitude during fixation obeyed Maxwell's law for each participant and for each scene condition (normal or scrambled). The results suggest that eye fixation during natural scene perception describes a random motion regardless of top-down or of bottom-up processes. PMID:23226987

  10. Drill cuttings mount formation study

    Science.gov (United States)

    Teh, Su Yean; Koh, Hock Lye

    2014-07-01

    Oil, Gas and Energy sector has been identified as an essential driving force in the Malaysian Economic Transformation Programs (ETP). Recently confirmed discovery of many offshore oil and gas deposits in Malaysian waters has ignited new confidence in this sector. However, this has also spurred intense interest on safeguarding the health and environment of coastal waters in Malaysia from adverse impact resulting from offshore oil and gas production operation. Offshore discharge of spent drilling mud and rock cuttings is the least expensive and simplest option to dispose of large volumes of drilling wastes. But this onsite offshore disposal may have adverse environmental impacts on the water column and the seabed. It may also pose occupational health hazards to the workers living in the offshore platforms. It is therefore important to model the transport and deposition of drilling mud and rock cuttings in the sea to enable proper assessment of their adverse impacts on the environment and the workers. Further, accumulation of drill particles on the seabed may impede proper operation of pipelines on the seabed. In this paper, we present an in-house application model TUNA-PT developed to cater to local oil and gas industry needs to simulate the dispersion and mount formation of drill cuttings by offshore oil and gas exploration and production platforms. Using available data on Malaysian coastal waters, simulation analyses project a pile formation on the seabed with a maximum height of about 1 m and pile radius of around 30 to 50 m. Simulated pile heights are not sensitive to the heights of release of the cuttings as the sensitivity has been mitigated by the depth of water.

  11. A Survey of Calibration Methods for Optical See-Through Head-Mounted Displays

    OpenAIRE

    Grubert, Jens; Itoh, Yuta; Moser, Kenneth; Swan II, J. Edward

    2017-01-01

    Optical see-through head-mounted displays (OST HMDs) are a major output medium for Augmented Reality, which have seen significant growth in popularity and usage among the general public due to the growing release of consumer-oriented models, such as the Microsoft Hololens. Unlike Virtual Reality headsets, OST HMDs inherently support the addition of computer-generated graphics directly into the light path between a user's eyes and their view of the physical world. As with most Augmented and Vi...

  12. Rotational symmetric HMD with eye-tracking capability

    Science.gov (United States)

    Liu, Fangfang; Cheng, Dewen; Wang, Qiwei; Wang, Yongtian

    2016-10-01

    As an important auxiliary function of head-mounted displays (HMDs), eye tracking has an important role in the field of intelligent human-machine interaction. In this paper, an eye-tracking HMD system (ET-HMD) is designed based on the rotational symmetric system. The tracking principle in this paper is based on pupil-corneal reflection. The ET-HMD system comprises three optical paths for virtual display, infrared illumination, and eye tracking. The display optics is shared by three optical paths and consists of four spherical lenses. For the eye-tracking path, an extra imaging lens is added to match the image sensor and achieve eye tracking. The display optics provides users a 40° diagonal FOV with a ״ 0.61 OLED, the 19 mm eye clearance, and 10 mm exit pupil diameter. The eye-tracking path can capture 15 mm × 15 mm of the users' eyes. The average MTF is above 0.1 at 26 lp/mm for the display path, and exceeds 0.2 at 46 lp/mm for the eye-tracking path. Eye illumination is simulated using LightTools with an eye model and an 850 nm near-infrared LED (NIR-LED). The results of the simulation show that the illumination of the NIR-LED can cover the area of the eye model with the display optics that is sufficient for eye tracking. The integrated optical system HMDs with eye-tracking feature can help improve the HMD experience of users.

  13. Eye movements of patients with tunnel vision while walking.

    Science.gov (United States)

    Vargas-Martín, Fernando; Peli, Eli

    2006-12-01

    To determine how severe peripheral field loss (PFL) affects the dispersion of eye movements relative to the head in patients walking in real environments. This information should help to define the visual field and clearance requirements for head-mounted mobility visual aids. Eye positions relative to the head were recorded in five patients with retinitis pigmentosa who had less than 15 degrees of visual field and in three normally sighted people, each walking in varied environments for more than 30 minutes. The eye-position recorder was made portable by modifying a head-mounted system (ISCAN, Burlington, MA). Custom data processing was implemented, to reject unreliable data. Sample standard deviations of eye position (dispersion) were compared across subject groups and environments. The patients with PFL exhibited narrower horizontal eye-position dispersions than did the normally sighted subjects (9.4 degrees vs. 14.2 degrees , P vision information. Their horizontal scanning was actually reduced, possibly because of lack of peripheral stimulation. The results suggest that a field of view as wide as 40 degrees may be needed for closed (immersive) head-mounted mobility aids, whereas a much narrower display, perhaps as narrow as 20 degrees , may be sufficient with an open design.

  14. The fly's eye camera system

    Science.gov (United States)

    Mészáros, L.; Pál, A.; Csépány, G.; Jaskó, A.; Vida, K.; Oláh, K.; Mezö, G.

    2014-12-01

    We introduce the Fly's Eye Camera System, an all-sky monitoring device intended to perform time domain astronomy. This camera system design will provide complementary data sets for other synoptic sky surveys such as LSST or Pan-STARRS. The effective field of view is obtained by 19 cameras arranged in a spherical mosaic form. These individual cameras of the device stand on a hexapod mount that is fully capable of achieving sidereal tracking for the subsequent exposures. This platform has many advantages. First of all it requires only one type of moving component and does not include unique parts. Hence this design not only eliminates problems implied by unique elements, but the redundancy of the hexapod allows smooth operations even if one or two of the legs are stuck. In addition, it can calibrate itself by observed stars independently from both the geographical location (including northen and southern hemisphere) and the polar alignment of the full mount. All mechanical elements and electronics are designed within the confines of our institute Konkoly Observatory. Currently, our instrument is in testing phase with an operating hexapod and reduced number of cameras.

  15. Flow distortion on boom mounted cup anemometers

    DEFF Research Database (Denmark)

    Lindelöw, Per Jonas Petter; Friis Pedersen, Troels; Gottschall, Julia

    In this report we investigate on wind direction dependent errors in the measurement of the horizontal wind speed by boom mounted cup anemometers. The boom mounting on the studied lattice tower is performed according to IEC standard design rules, yet, larger deviations than predicted by flow models...... are observed. The errors on the measurements are likely caused by an underestimation of the flow distortions around the tower. In this paper an experimental method for deriving a correction formula and an in-field calibration is suggested. The method is based on measurements with two cup anemometers mounted...

  16. Automated sample mounting and technical advance alignment system for biological crystallography at a synchrotron source

    International Nuclear Information System (INIS)

    Snell, Gyorgy; Cork, Carl; Nordmeyer, Robert; Cornell, Earl; Meigs, George; Yegian, Derek; Jaklevic, Joseph; Jin, Jian; Stevens, Raymond C.; Earnest, Thomas

    2004-01-01

    High-throughput data collection for macromolecular crystallography requires an automated sample mounting system for cryo-protected crystals that functions reliably when integrated into protein-crystallography beamlines at synchrotrons. Rapid mounting and dismounting of the samples increases the efficiency of the crystal screening and data collection processes, where many crystals can be tested for the quality of diffraction. The sample-mounting subsystem has random access to 112 samples, stored under liquid nitrogen. Results of extensive tests regarding the performance and reliability of the system are presented. To further increase throughput, we have also developed a sample transport/storage system based on 'puck-shaped' cassettes, which can hold sixteen samples each. Seven cassettes fit into a standard dry shipping Dewar. The capabilities of a robotic crystal mounting and alignment system with instrumentation control software and a relational database allows for automated screening and data collection to be developed

  17. Biodiversity of the flora of Mount Papa

    International Nuclear Information System (INIS)

    Yin-Yin-Kyi

    1995-07-01

    Even though Mount Papa is in the dry zone area, it is almost evergreen, due to its elevation of 4981 feet above the sea level and its fertile soil conditions. A has a rich biodiversity with vegetation of many types

  18. May 1980 Mount Saint Helens, USA Images

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — An earthquake occurred at 15 32 UT, only seconds before the explosion that began the eruption of Mount St. Helens volcano. This eruption and blast blew off the top...

  19. Photoelectric panel with equatorial mounting of drive

    Science.gov (United States)

    Kukhta, M. S.; Krauinsh, P. Y.; Krauinsh, D. P.; Sokolov, A. P.; Mainy, S. B.

    2018-03-01

    The relevance of the work is determined by the need to create effective models for sunny energy. The article considers a photoelectric panel equipped with a system for tracking the sun. Efficiency of the system is provided by equatorial mounting, which compensates for the rotation of the Earth by rotating the sunny panel in the plane of the celestial equator. The specificity of climatic and geographical conditions of Tomsk is estimated. The dynamics of power variations of photoelectric panels with equatorial mounting during seasonal fluctuations in Tomsk is calculated. A mobile photovoltaic panel with equatorial mounting of the drive has been developed. The methods of design strategy for placing photovoltaic panels in the architectural environment of the city are presented. Key words: sunny energy, photovoltaics, equatorial mounting, mechatronic model, wave reducer, electric drive.

  20. A model for investigating developmental eye repair in Xenopus laevis.

    Science.gov (United States)

    Kha, Cindy X; Son, Philip H; Lauper, Julia; Tseng, Kelly Ai-Sun

    2018-04-01

    Vertebrate eye development is complex and requires early interactions between neuroectoderm and surface ectoderm during embryogenesis. In the African clawed frog, Xenopus laevis, individual eye tissues such as the retina and lens can undergo regeneration. However, it has been reported that removal of either the specified eye field at the neurula stage or the eye during tadpole stage does not induce replacement. Here we describe a model for investigating Xenopus developmental eye repair. We found that tailbud embryos can readily regrow eyes after surgical removal of over 83% of the specified eye and lens tissues. The regrown eye reached a comparable size to the contralateral control by 5 days and overall animal development was normal. It contained the expected complement of eye cell types (including the pigmented epithelium, retina and lens), and is connected to the brain. Our data also demonstrate that apoptosis, an early mechanism that regulates appendage regeneration, is also required for eye regrowth. Treatment with apoptosis inhibitors (M50054 or NS3694) blocked eye regrowth by inhibiting caspase activation. Together, our findings indicate that frog embryos can undergo successful eye repair after considerable tissue loss and reveals a required role for apoptosis in this process. Furthermore, this Xenopus model allows for rapid comparisons of productive eye repair and developmental pathways. It can also facilitate the molecular dissection of signaling mechanisms necessary for initiating repair. Copyright © 2018 The Authors. Published by Elsevier Ltd.. All rights reserved.

  1. Eyes Wide Open

    Directory of Open Access Journals (Sweden)

    Zoi Manesi

    2016-04-01

    Full Text Available Research from evolutionary psychology suggests that the mere presence of eye images can promote prosocial behavior. However, the “eye images effect” is a source of considerable debate, and findings across studies have yielded somewhat inconsistent support. We suggest that one critical factor may be whether the eyes really need to be watching to effectively enhance prosocial behavior. In three experiments, we investigated the impact of eye images on prosocial behavior, assessed in a laboratory setting. Participants were randomly assigned to view an image of watching eyes (eyes with direct gaze, an image of nonwatching eyes (i.e., eyes closed for Study 1 and averted eyes for Studies 2 and 3, or an image of flowers (control condition. Upon exposure to the stimuli, participants decided whether or not to help another participant by completing a dull cognitive task. Three independent studies produced somewhat mixed results. However, combined analysis of all three studies, with a total of 612 participants, showed that the watching component of the eyes is important for decision-making in this context. Images of watching eyes led to significantly greater inclination to offer help as compared to images of nonwatching eyes (i.e., eyes closed and averted eyes or images of flowers. These findings suggest that eyes gazing at an individual, rather than any proxy to social presence (e.g., just the eyes, serve as a reminder of reputation. Taken together, we conclude that it is “eyes that pay attention” that can lift the veil of anonymity and potentially facilitate prosocial behavior.

  2. Isolation Mounting for Charge-Coupled Devices

    Science.gov (United States)

    Goss, W. C.; Salomon, P. M.

    1985-01-01

    CCD's suspended by wires under tension. Remote thermoelectric cooling of charge coupled device allows vibration isolating mounting of CCD assembly alone, without having to suspend entire mass and bulk of thermoelectric module. Mounting hardware simple and light. Developed for charge-coupled devices (CCD's) in infrared telescope support adaptable to sensors in variety of environments, e.g., sensors in nuclear reactors, engine exhausts and plasma chambers.

  3. "Split Cast Mounting: Review and New Technique".

    Science.gov (United States)

    Gundawar, S M; Pande, Neelam A; Jaiswal, Priti; Radke, U M

    2014-12-01

    For the fabrication of a prosthesis, the Prosthodontist meticulously performs all the steps. The laboratory technician then make every effort/strives to perform the remaining lab procedures. However when the processed dentures are remounted on the articulator, some changes are seen. These changes may be divided into two categories: Pre-insertion and post-insertion changes, which deal with the physical properties of the materials involved (Parker, J Prosthet Dent 31:335-342, 1974). Split cast mounting is the method of mounting casts on the articulator. It is essentially a maxillary cast constructed in two parts with a horizontal division. The procedure allows for the verification of the accuracy of the initial mounting and the ease of removal and replacement of the cast. This provides a precise means of correcting the changes in occlusion occurring as a result of the processing technique (Nogueira et al., J Prosthet Dent 91:386-388, 2004). Instability of the split mounting has always been a problem to the Prosthodontist thereby limiting its use. There are various materials mentioned in the literature. The new technique by using Dowel pins and twill thread is very easy, cheaper and simple way to stabilize the split mounting. It is useful and easy in day to day laboratory procedures. The article presents different methods of split cast mounting and the new procedure using easily available materials in prosthetic laboratory.

  4. Preliminary study of ergonomic behavior during simulated ultrasound-guided regional anesthesia using a head-mounted display.

    Science.gov (United States)

    Udani, Ankeet D; Harrison, T Kyle; Howard, Steven K; Kim, T Edward; Brock-Utne, John G; Gaba, David M; Mariano, Edward R

    2012-08-01

    A head-mounted display provides continuous real-time imaging within the practitioner's visual field. We evaluated the feasibility of using head-mounted display technology to improve ergonomics in ultrasound-guided regional anesthesia in a simulated environment. Two anesthesiologists performed an equal number of ultrasound-guided popliteal-sciatic nerve blocks using the head-mounted display on a porcine hindquarter, and an independent observer assessed each practitioner's ergonomics (eg, head turning, arching, eye movements, and needle manipulation) and the overall block quality based on the injectate spread around the target nerve for each procedure. Both practitioners performed their procedures without directly viewing the ultrasound monitor, and neither practitioner showed poor ergonomic behavior. Head-mounted display technology may offer potential advantages during ultrasound-guided regional anesthesia.

  5. Analysis of adjusting effects of mounting force on frequency conversion of mounted nonlinear optics.

    Science.gov (United States)

    Su, Ruifeng; Liu, Haitao; Liang, Yingchun; Lu, Lihua

    2014-01-10

    Motivated by the need to increase the second harmonic generation (SHG) efficiency of nonlinear optics with large apertures, a novel mounting configuration with active adjusting function on the SHG efficiency is proposed and mechanically and optically studied. The adjusting effects of the mounting force on the distortion and stress are analyzed by the finite element methods (FEM), as well as the contribution of the distortion and stress to the change in phase mismatch, and the SHG efficiency are theoretically stated. Further on, the SHG efficiency is calculated as a function of the mounting force. The changing trends of the distortion, stress, and the SHG efficiency with the varying mounting force are obtained, and the optimal ones are figured out. Moreover, the mechanism of the occurrence of the optimal values is studied and the adjusting strategy is put forward. Numerical results show the robust adjustment of the mounting force, as well as the effectiveness of the mounting configuration, in increasing the SHG efficiency.

  6. What Is Dry Eye?

    Medline Plus

    Full Text Available ... Kierstan Boyd Reviewed By: Brenda Pagan-Duran MD Sep. 01, 2017 Our eyes need tears to stay ... tear duct to insert a permanent punctal plug? Sep 12, 2017 Why are my eyes bloodshot when ...

  7. What Is Dry Eye?

    Medline Plus

    Full Text Available ... seasonal allergens and dry eye Apr 27, 2015 Choosing Wisely When It Comes to Eye Care, Part ... Name: Member ID: * Phone Number: * Email: * Enter code: * Message: Thank you Your feedback has been sent.

  8. About the Eye

    Medline Plus

    Full Text Available ... Disease Education Program Glaucoma Education Program Low Vision Education Program ... Eye Ask a Scientist Video Series Glossary The Visual System Your Eyes’ Natural Defenses Eye Health and Safety ...

  9. Pink Eye (Conjunctivitis)

    Science.gov (United States)

    ... or child care if you're not able to take time off — just stay consistent in practicing good hygiene. Preventing pink eye in newborns Newborns' eyes are susceptible to bacteria normally present in the mother's birth canal. ...

  10. About the Eye

    Medline Plus

    Full Text Available ... Ask a Scientist Video Series Glossary The Visual System Your Eyes’ Natural Defenses Eye Health and Safety ... much as it does on your eyes. ... of Health | USA.gov NIH…Turning Discovery Into Health ®

  11. About the Eye

    Medline Plus

    Full Text Available ... Eye Institute’s mission is to “conduct and support research, training, health information dissemination, and other programs with respect to blinding eye diseases, visual disorders, mechanisms of visual function, preservation of sight, and the ...

  12. Preventing Eye Injuries

    Science.gov (United States)

    ... Your Eyes Sep 20, 2017 Eye Injuries from Laundry Packets On the Rise Jun 30, 2017 ... Medical Disclaimer Privacy Policy Terms of Service For Advertisers For Media Ophthalmology Job Center © American ...

  13. About the Eye

    Medline Plus

    Full Text Available ... National Eye Institute’s mission is to “conduct and support research, training, health information dissemination, and other programs with respect to blinding eye diseases, visual disorders, mechanisms of visual function, preservation of sight, ...

  14. What Is Dry Eye?

    Medline Plus

    Full Text Available ... Eye Health Home Annual Meeting Clinical Education Practice Management Member Services Advocacy Foundation About Subspecialties & More Academy Publications EyeNet Ophthalmology Ophthalmology Retina Information for: International Ophthalmologists Media Medical Students Patients and ...

  15. What Is Dry Eye?

    Medline Plus

    Full Text Available ... right type of tears or tear film . How do tears work? When you blink, a film of ... layer cleans the eye, washing away particles that do not belong in the eye. This layer comes ...

  16. About the Eye

    Medline Plus

    Full Text Available ... The Visual System Your Eyes’ Natural Defenses Eye Health and Safety First Aid ... Your eyes are made up of many different parts that work together to help you see. Check out the ...

  17. About the Eye

    Medline Plus

    Full Text Available ... Vision Education Program Hispanic/Latino Program Vision and Aging Program African American Program Training and Jobs Fellowships ... Defenses Eye Health and Safety First Aid Tips Healthy Vision Tips Protective Eyewear Sports and Your Eyes ...

  18. About the Eye

    Medline Plus

    Full Text Available ... Clinical Director Laboratories, Sections and Units Division of Epidemiology and Clinical Applications eyeGENE Research Directors Office Office ... Diabetic Eye Disease Education Program Glaucoma Education Program Low Vision Education Program Hispanic/Latino Program Vision and ...

  19. About the Eye

    Medline Plus

    Full Text Available ... Home » NEI for Kids » About the Eye Listen All About Vision About the Eye Ask a Scientist ... you can see and make sense of the world around you. Did You Know? Vision depends on ...

  20. About the Eye

    Medline Plus

    Full Text Available ... search for current job openings visit HHS USAJobs Home >> NEI for Kids >> About the Eye Listen All ... much as it does on your eyes. NEI Home Contact Us A-Z Site Map NEI on ...

  1. About the Eye

    Medline Plus

    Full Text Available ... NIH), the National Eye Institute’s mission is to “conduct and support research, training, health information dissemination, and other programs with respect to blinding eye diseases, visual disorders, mechanisms of visual function, preservation of ...

  2. Eye Involvement in TSC

    Science.gov (United States)

    ... eye involvement. Nonretinal and Retinal Eye Findings Facial angiofibromas may involve the eyelids of individuals with TSC, ... the hamartomas have many blood vessels (as are angiofibromas of the skin). Less than half of the ...

  3. What Is Dry Eye?

    Medline Plus

    Full Text Available ... removed or pushed down the tear duct to insert a permanent punctal plug? Sep 12, 2017 Why ... Eye from Jennifer Aniston Sep 02, 2016 The link between seasonal allergens and dry eye Apr 27, ...

  4. What Is Dry Eye?

    Medline Plus

    Full Text Available ... Services Advocacy Foundation About Subspecialties & More Eye Health Home Annual Meeting Clinical Education Practice Management Member Services Advocacy Foundation About Subspecialties & More Academy Publications EyeNet ...

  5. About the Eye

    Medline Plus

    Full Text Available ... First Aid Tips Healthy Vision Tips Protective Eyewear Sports and Your Eyes Fun Stuff Cool Eye Tricks ... website is maintained by the NEI Office of Science Communications, Public Liaison, and Education. Technical questions about ...

  6. About the Eye

    Medline Plus

    Full Text Available ... search for current job openings visit HHS USAJobs Home » NEI for Kids » About the Eye Listen All ... much as it does on your eyes. NEI Home Contact Us A-Z Site Map NEI on ...

  7. About the Eye

    Medline Plus

    Full Text Available ... the special health problems and requirements of the blind.” News & Events Events Calendar NEI Press Releases News ... First Aid Tips Healthy Vision Tips Protective Eyewear Sports and Your Eyes Fun Stuff Cool Eye Tricks ...

  8. Immunology of the eye

    OpenAIRE

    Weronika Ratajczak; Beata Tokarz-Deptuła; Wiesław Deptuła

    2018-01-01

    The eye is an organ of sight characterized by unusual immunological properties, resulting from its anatomical structure and physiology, as well as the presence of specific elements that, through the mechanisms of innate and adaptive immunity, provide homeostasis of the eyeball. This article reviews the defensive elements of individual eye structures: conjunctiva, cornea, lacrimal gland, anterior chamber of the eye, uvea, retina and eye-associated lymphoid tissue (EALT), where we distinguish a...

  9. Technical preparation of the Yuzhteploehnergomontazh trust for technological equipment mounting

    International Nuclear Information System (INIS)

    Zayats, A.I.

    1982-01-01

    Measures of technical preparation for equipment mounting at the Zaporozhe NPP developed with the Yuzhteploehnergomontazh trust experts are considered. These measures envisage the construction of mounting base of heat facilities, calculation of labour contents and determination of necessary quantity of mounters, development of optimal flowsheet of mounting control, improvement of mounting qualification and creation of stable collective body, improvement of technical level of mounting and welding works, organizational-technical measures on mounting logistics. Factors affecting negatively technical preparation quality of equipment mounting at the Zaporozhe NPP are discussed. The flowsheet of mounting control is presented

  10. The all seeing eye?

    NARCIS (Netherlands)

    Koenderink, Jan J.

    2014-01-01

    The All Seeing Eye? Did you know that you are probably a believer in the All Seeing Eye? The odds are that I’m right—why? Well, the bulk of mainstream vision literature blindly relies on the All Seeing Eye. It is written all over papers, albeit between the lines. Understandably so, for scientists

  11. About the Eye

    Medline Plus

    Full Text Available ... other programs with respect to blinding eye diseases, visual disorders, mechanisms of visual function, preservation of sight, and the special health ... Eye Ask a Scientist Video Series Glossary The Visual System Your Eyes’ Natural Defenses Eye Health and ...

  12. Dwarf Eye Disorder

    Science.gov (United States)

    Science Teacher, 2005

    2005-01-01

    Johns Hopkins researchers at the Wilmer Eye Institute have discovered what appears to be the first human gene mutation that causes extreme farsightedness. The researchers report that nanophthalmos, Greek for "dwarf eye," is a rare, potentially blinding disorder caused by an alteration in a gene called MFRP that helps control eye growth and…

  13. Fish eye optics

    Science.gov (United States)

    Hudec, R.; Michalova, S.

    2017-07-01

    We report on small student (high—school) project of the Czech Academy of Sciences dealing with animal (fish) eyes and possible application in science and technology. Albeit most fishes have refractive eyes, the recent discoveries confirm that some fishes have reflective eyes with strange arrangements as well.

  14. Eye and orbital cavity

    International Nuclear Information System (INIS)

    Panfilova, G.V.; Koval', G.Yu.

    1984-01-01

    Radioanatomy of eyes and orbit is described. Diseases of the orbit (developmental anomalies, inflammatory diseases, lacrimal apparatus deseases, toxoplasmosis, tumors and cysts et al.), methods of foreign body localization in the eye are considered. Roentgenograms of the orbit and calculation table for foreign body localization in spherical eyes of dissimilar diameter are presented

  15. Recognizing and Treating Eye Injuries

    Science.gov (United States)

    ... Eye Injuries First Aid for Eye Scratches Protective Eyewear Children’s Eye Injuries: Prevention and Care Eye Injuries ... Academy Jobs at the Academy Financial Relationships with Industry Medical Disclaimer Privacy Policy Terms of Service For ...

  16. EYE GAZE TRACKING

    DEFF Research Database (Denmark)

    2017-01-01

    This invention relates to a method of performing eye gaze tracking of at least one eye of a user, by determining the position of the center of the eye, said method comprising the steps of: detecting the position of at least three reflections on said eye, transforming said positions to spanning...... a normalized coordinate system spanning a frame of reference, wherein said transformation is performed based on a bilinear transformation or a non linear transformation e.g. a möbius transformation or a homographic transformation, detecting the position of said center of the eye relative to the position...... of said reflections and transforming this position to said normalized coordinate system, tracking the eye gaze by tracking the movement of said eye in said normalized coordinate system. Thereby calibration of a camera, such as knowledge of the exact position and zoom level of the camera, is avoided...

  17. Diquafosol ophthalmic solution for dry eye treatment.

    Science.gov (United States)

    Nakamura, Masatsugu; Imanaka, Takahiro; Sakamoto, Asuka

    2012-07-01

    There has been rapid progress in our understanding of dry eye pathogenesis, as well as the development of improved diagnostic clinical tests. Various types of dry eye treatment drugs have been developed. This review summarizes the basic and clinical research carried out in the development of diquafosol for ophthalmic use. Diquafosol is a dinucleotide, purinoreceptor P2Y(2) receptor agonist. Basic pharmacological studies have shown that it acts on P2Y(2) receptors at the ocular surface, to promote tear and mucin secretion via elevated intracellular Ca(2+) concentrations. Diquafosol also improves tear and mucin secretion in experimental dry eye models. Based on the results of laboratory experiments, the authors conducted a series of clinical studies in patients with dry eye disease. Diquafosol was effective in the treatment of dry eye disease at an optimal dose of 3% six times a day. In comparison to commercially available 0.1% sodium hyaluronate ophthalmic solution, 3% diquafosol ophthalmic solution showed non-inferiority in improving corneal fluorescein staining scores and superiority in improving keratoconjunctival Rose Bengal staining scores. Diquafosol ophthalmic solution has a novel mechanism of action that is characterized by its stimulatory effects on tear and mucin secretion. This drug has the potential to be effective in patients with tear film instability and short break-up time type of dry eye, which are essential factors in dry eye pathogenesis.

  18. 76 FR 76689 - Cibola National Forest, Mount Taylor Ranger District, NM, Mount Taylor Combined Exploratory Drilling

    Science.gov (United States)

    2011-12-08

    ... National Forest, Mount Taylor Ranger District, NM, Mount Taylor Combined Exploratory Drilling AGENCY... proposed action is to approve two Plans of Operations for exploratory uranium drilling on the Cibola... San Mateo. In total, there are up to 279 drill holes that would be drilled over a period not to exceed...

  19. Eye Contact Facilitates Awareness of Faces during Interocular Suppression

    Science.gov (United States)

    Stein, Timo; Senju, Atsushi; Peelen, Marius V.; Sterzer, Philipp

    2011-01-01

    Eye contact captures attention and receives prioritized visual processing. Here we asked whether eye contact might be processed outside conscious awareness. Faces with direct and averted gaze were rendered invisible using interocular suppression. In two experiments we found that faces with direct gaze overcame such suppression more rapidly than…

  20. Ball mounting fixture for a roundness gage

    Science.gov (United States)

    Gauler, Allen L.; Pasieka, Donald F.

    1983-01-01

    A ball mounting fixture for a roundness gage is disclosed. The fixture includes a pair of chuck assemblies oriented substantially transversely with respect to one another and mounted on a common base. Each chuck assembly preferably includes a rotary stage and a wobble plate affixed thereto. A ball chuck affixed to each wobble plate is operable to selectively support a ball to be measured for roundness, with the wobble plate permitting the ball chuck to be tilted to center the ball on the axis of rotation of the rotary stage. In a preferred embodiment, each chuck assembly includes a vacuum chuck operable to selectively support the ball to be measured for roundness. The mounting fixture enables a series of roundness measurements to be taken with a conventional rotating gagehead roundness instrument, which measurements can be utilized to determine the sphericity of the ball.

  1. Mounting system for optical frequency reference cavities

    Science.gov (United States)

    Notcutt, Mark (Inventor); Hall, John L. (Inventor); Ma, Long-Sheng (Inventor)

    2008-01-01

    A technique for reducing the vibration sensitivity of laser-stabilizing optical reference cavities is based upon an improved design and mounting method for the cavity, wherein the cavity is mounted vertically. It is suspended at one plane, around the spacer cylinder, equidistant from the mirror ends of the cavity. The suspension element is a collar of an extremely low thermal expansion coefficient material, which surrounds the spacer cylinder and contacts it uniformly. Once the collar has been properly located, it is cemented in place so that the spacer cylinder is uniformly supported and does not have to be squeezed at all. The collar also includes a number of cavities partially bored into its lower flat surface, around the axial bore. These cavities are support points, into which mounting base pins will be inserted. Hence the collar is supported at a minimum of three points.

  2. Reading strategies in mild to moderate strabismic amblyopia: an eye movement investigation.

    Science.gov (United States)

    Kanonidou, Evgenia; Proudlock, Frank A; Gottlob, Irene

    2010-07-01

    PURPOSE. To investigate oculomotor strategies in strabismic amblyopia and evaluate abnormalities during monocular and binocular reading. METHODS. Eye movements were recorded with a head-mounted infrared video eye-tracker (250 Hz, amblyopia, reading is impaired, not only during monocular viewing with the amblyopic eye, but also with the nonamblyopic eye and binocularly, even though normal visual acuity pertains to the latter two conditions. The impaired reading performance is associated with differences in both the saccadic and fixational patterns, most likely as adaptation strategies to abnormal sensory experiences such as crowding and suppression.

  3. 14 CFR 33.23 - Engine mounting attachments and structure.

    Science.gov (United States)

    2010-01-01

    ... 14 Aeronautics and Space 1 2010-01-01 2010-01-01 false Engine mounting attachments and structure... mounting attachments and structure. (a) The maximum allowable limit and ultimate loads for engine mounting attachments and related engine structure must be specified. (b) The engine mounting attachments and related...

  4. Robotic mounting of ATLAS barrel SCT modules

    International Nuclear Information System (INIS)

    Nickerson, R.B.; Viehhauser, G.; Wastie, R.; Terada, S.; Unno, Y.; Kohriki, T.; Ikegami, Y.; Hara, K.; Kobayashi, H.; Barbier, G.; Clark, A.G.; Perrin, E.; Carter, A.A.; Mistry, J.; Morris, J.

    2006-01-01

    The 2112 silicon detector modules of the barrel part of the ATLAS SemiConductor Tracker (SCT) have been mounted on their carbon fibre support structure. Module insertion, placement and fixing were performed by robotic assembly tooling. We report on our experience with this assembly method. Part of the mounting sequence involves a partial survey of elements of the support structure which is needed to align the modules properly during insertion. An analysis of these data is used to estimate the positional accuracy of the robots

  5. Sensor mount assemblies and sensor assemblies

    Science.gov (United States)

    Miller, David H [Redondo Beach, CA

    2012-04-10

    Sensor mount assemblies and sensor assemblies are provided. In an embodiment, by way of example only, a sensor mount assembly includes a busbar, a main body, a backing surface, and a first finger. The busbar has a first end and a second end. The main body is overmolded onto the busbar. The backing surface extends radially outwardly relative to the main body. The first finger extends axially from the backing surface, and the first finger has a first end, a second end, and a tooth. The first end of the first finger is disposed on the backing surface, and the tooth is formed on the second end of the first finger.

  6. Organization of eye bank

    International Nuclear Information System (INIS)

    Reddy, S.C.

    1999-01-01

    Comeal transplantation is the only method of combating the blindness due to corneal opacity caused by infections, malnutrition, trauma and hereditary diseases. Comeal blindness is more prevalent in the developing countries. The availability of the donor cornea, trained ophthalmic surgeons and microsurgery facilities are the key factors in restoring vision in-patients with comeal blindness. The eye bank organization is somewhat similar to that of blood bank. The eye bank should be located in a hospital or a medical centre in which a laboratory may be established for the evaluation and storage of donor tissue. The medical director (Ophthalmologist), technician, secretary and public relation officer are the persons who play an important role in the successful organization of eye bank. The function of the eye bank are procurement, assessment, processing, distribution of donor eyes/corneas, training of technicians/doctors, and conducting research related to storage of donor tissue and corneal transplantation. The necessary infrastructure required for the organization of an eye bank include separate accommodation area for the personnel and the laboratory, telephone, computer, refrigerator, laminar air flow hood. Slitlamp, specular microscope, storage media and equipment, instrument for enucleation of donor eyes, and a motor vehicle. The details of responsibilities of the staff of eye bank, source of donor eyes, suitability of donor material, procurement of the donor cornea, tissue assessment, storage and preservation, distribution of donor tissue, and limitation of eye bank will be discussed at the time of presentation

  7. Exaggerated displays do not improve mounting success in male seaweed flies Fucellia tergina (Diptera: Anthomyiidae).

    Science.gov (United States)

    Memmott, Ruth; Briffa, Mark

    2015-11-01

    Signals of individual quality are assumed to be difficult to exaggerate, either because they are directly linked to underlying traits (indices) or because they are costly to perform (handicaps). In practise advertisement displays may consist of conventional and costly components, for instance where a morphological structure related to body size is used in visual displays. In this case, there is the potential for dishonest displays, due to the population level variance around the relationship between body size and display structures. We examine the use of wing flicking displays that we observed in situ in a strandline dwelling seaweed fly Fucellia tergina, using overall body size and the size of their eyes as underlying indicators of condition. Males displayed far more frequently than females, and were also observed to frequently mount other flies, a behaviour that was rare in females. The rate of display was greater for males that had positive residual values from relationships between wing length and body length. In other words those males with larger than expected wings for their underlying quality displayed more frequently, indicating that these displays are open to exaggeration. Males with larger than expected wings (for the size of their body or eyes), however, mounted less frequently. We suggest that small bodied males are less successful in terms of mounting, but that those small males with relatively large wings may attempt to compensate for this through increased display effort. Copyright © 2015 Elsevier B.V. All rights reserved.

  8. EyeMusic: Making Music with the Eyes

    OpenAIRE

    Hornof, Anthony J.; Sato, Linda

    2004-01-01

    Though musical performers routinely use eye movements to communicate with each other during musical performances, very few performers or composers have used eye tracking devices to direct musical compositions and performances. EyeMusic is a system that uses eye movements as an input to electronic music compositions. The eye movements can directly control the music, or the music can respond to the eyes moving around a visual scene. EyeMusic is implemented so that any composer using established...

  9. Fixture For Mounting A Pressure Sensor

    Science.gov (United States)

    Cagle, Christopher M.

    1995-01-01

    Fixture for mounting pressure sensor in aerodynamic model simplifies task of removal and replacement of sensor in event sensor becomes damaged. Makes it unnecessary to dismantle model. Also minimizes any change in aerodynamic characteristics of model in event of replacement. Removable pressure sensor installed in fixture in wall of model. Wires from sensor pass through channel under surface.

  10. Creating Gaze Annotations in Head Mounted Displays

    DEFF Research Database (Denmark)

    Mardanbeigi, Diako; Qvarfordt, Pernilla

    2015-01-01

    To facilitate distributed communication in mobile settings, we developed GazeNote for creating and sharing gaze annotations in head mounted displays (HMDs). With gaze annotations it possible to point out objects of interest within an image and add a verbal description. To create an annota- tion...

  11. Flush-mounting technique for composite beams

    Science.gov (United States)

    Harman, T. C.; Kay, B. F.

    1980-01-01

    Procedure permits mounting of heavy parts to surface of composite beams without appreciably weakening beam web. Web is split and held apart in region where attachment is to be made by lightweight precast foam filler. Bolt hole penetrates foam rather than web, and is secured by barrelnut in transverse bushing through web.

  12. Bearing-Mounting Concept Accommodates Thermal Expansion

    Science.gov (United States)

    Nespodzany, Robert; Davis, Toren S.

    1995-01-01

    Pins or splines allow radial expansion without slippage. Design concept for mounting rotary bearing accommodates differential thermal expansion between bearing and any structure(s) to which bearing connected. Prevents buildup of thermal stresses by allowing thermal expansion to occur freely but accommodating expansion in such way not to introduce looseness. Pin-in-slot configuration also maintains concentricity.

  13. Motion planning for gantry mounted manipulators

    DEFF Research Database (Denmark)

    Olsen, Anders Lau; Petersen, Henrik Gordon

    2007-01-01

    We present a roadmap based planner for finding robot motions for gantry mounted manipulators for a line welding application at Odense Steel Shipyard (OSS). The robot motions are planned subject to constraints on when the gantry may be moved. We show that random sampling of gantry configurations...

  14. Photovoltaic module mounting clip with integral grounding

    Science.gov (United States)

    Lenox, Carl J.

    2010-08-24

    An electrically conductive mounting/grounding clip, usable with a photovoltaic (PV) assembly of the type having an electrically conductive frame, comprises an electrically conductive body. The body has a central portion and first and second spaced-apart arms extending from the central portion. Each arm has first and second outer portions with frame surface-disrupting element at the outer portions.

  15. Mounting LHCb hadron calorimeter scintillating tiles

    CERN Multimedia

    Maximilien Brice

    2004-01-01

    Scintillating tiles are carefully mounted in the hadronic calorimeter for the LHCb detector. These calorimeters measure the energy of particles that interact via the strong force, called hadrons. The detectors are made in a sandwich-like structure where these scintillator tiles are placed between metal sheets.

  16. Solidly Mounted Resonator with Optimized Acoustic Reflector

    NARCIS (Netherlands)

    Jose, Sumy; Jansman, Andreas; Hueting, Raymond Josephus Engelbart

    2009-01-01

    The quality factor (Q) of the Solidly Mounted Resonator is limited by acoustic losses caused by waves leaking through the mirror stack. Traditionally employed acoustic mirror reflects only longitudinal waves and not shear waves. Starting with the stop-band theory and the principle of spacer layers

  17. Dynamic characteristics of mirrors' kinematic mount

    International Nuclear Information System (INIS)

    Wu Wenkai; Du Qiang; Li Jingze; Chen Gang; Chen Xiaojuan; Xu Yuanli

    2002-01-01

    Applying exact constrain design principles, kinematic mount for precision positioning large aperture mirrors is designed; theoretical method is introduced to analyze its dynamic characteristics and the result of the experiment for mirrors, stability; accordingly, the methods to improve design are put forward

  18. Making sense of Mount St. Helens

    Science.gov (United States)

    Steve Nash

    2010-01-01

    The eruption of Mount St. Helens in 1980 resulted in "a grand experiment that you could never have gotten anybody to fund," says Forest Service ecologist Charles Crisafulli. "Everything's new. It's a new landform." Unlike most misbehaving volcanoes, this one provided an accessible laboratory right along the Interstate-5 corridor, with the...

  19. June 1992 Mount Spurr, USA Images

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — Following 39 years of inactivity, Crater Peak vent on the south flank of Mount Spurr volcano burst into eruption at 7:04 a.m. Alaska daylight time (ADT) on June 27,...

  20. 49 CFR 587.19 - Mounting.

    Science.gov (United States)

    2010-10-01

    ... Other Regulations Relating to Transportation (Continued) NATIONAL HIGHWAY TRAFFIC SAFETY ADMINISTRATION, DEPARTMENT OF TRANSPORTATION (CONTINUED) DEFORMABLE BARRIERS Offset Deformable Barrier § 587.19 Mounting. (a) The deformable face is rigidly attached to the edge of the fixed rigid barrier or to some rigid...

  1. Eye Disease and Development

    DEFF Research Database (Denmark)

    Andersen, Thomas Barnebeck; Dalgaard, Carl-Johan Lars; Selaya, Pablo

    This research advances the hypothesis that cross-country variation in the historical incidence of eye disease has influenced the current global distribution of per capita income. The theory is that pervasive eye disease diminished the incentive to accumulate skills, thereby delaying the fertility...... transition and the take-off to sustained economic growth. In order to estimate the influence from eye disease incidence empirically, we draw on an important fact from the field of epidemiology: Exposure to solar ultraviolet B radiation (UVB-R) is an underlying determinant of several forms of eye disease...

  2. Inflammation in dry eye.

    Science.gov (United States)

    Stern, Michael E; Pflugfelder, Stephen C

    2004-04-01

    Dry eye is a condition of altered tear composition that results from a diseased or dysfunctional lacrimal functional unit. Evidence suggests that inflammation causes structural alterations and/or functional paralysis of the tear-secreting glands. Changes in tear composition resulting from lacrimal dysfunction, increased evaporation and/or poor clearance have pro-inflammatory effects on the ocular surface. This inflammation is responsible in part for the irritation symptoms, ocular surface epithelial disease, and altered corneal epithelial barrier function in dry eye. Anti-inflammatory therapies for dry eye target one or more of the inflammatory mediators/pathways that have been identified in dry eye.

  3. LASIK eye surgery

    Science.gov (United States)

    ... Assisted In Situ Keratomileusis; Laser vision correction; Nearsightedness - Lasik; Myopia - Lasik ... cornea (curvature) and the length of the eye. LASIK uses an excimer laser (an ultraviolet laser) to ...

  4. What Is Dry Eye?

    Medline Plus

    Full Text Available ... Ophthalmology Education Center Oculofacial Plastic Surgery Center Laser Surgery Education Center Redmond Ethics ... Services Advocacy Foundation About Subspecialties & More Eye ...

  5. Prevention of Eye Injuries

    OpenAIRE

    Pashby, Tom

    1981-01-01

    In Canada 30,000 people are registered as blind; in one third of these, blindness might have been avoided. Prevention is the key to reducing the number of eye injuries and blind eyes. The role of the family physician in early identification of treatable conditions and in the education of patients is discussed, but responsibility for prevention belongs to all physicians. The success of prevention is seen in the great reduction in eye injuries in industry and sports since eye protectors have be...

  6. What Is Dry Eye?

    Medline Plus

    Full Text Available ... Education Center Oculofacial Plastic Surgery Center Laser Surgery Education Center Redmond Ethics Center Global Ophthalmology Guide Academy Publications EyeNet Ophthalmology ...

  7. Bilateral Saccadic Eye Movements and Tactile Stimulation, but Not Auditory Stimulation, Enhance Memory Retrieval

    Science.gov (United States)

    Nieuwenhuis, Sander; Elzinga, Bernet M.; Ras, Priscilla H.; Berends, Floris; Duijs, Peter; Samara, Zoe; Slagter, Heleen A.

    2013-01-01

    Recent research has shown superior memory retrieval when participants make a series of horizontal saccadic eye movements between the memory encoding phase and the retrieval phase compared to participants who do not move their eyes or move their eyes vertically. It has been hypothesized that the rapidly alternating activation of the two hemispheres…

  8. Looking at vision : Eye/face/head tracking of consumers for improved marketing decisions

    NARCIS (Netherlands)

    Wedel, M.; Pieters, R.; Moutinho, L.; Bigné, E.; Manrai (eds.), A.K.

    Against the backdrop of the rapid growth of the use eye tracking and facial recognition methodology, this chapter discusses the measurement of eye movements, facial expression of emotions, pupil dilation, eye blinks and head movements. After discussing some of the main research findings in the

  9. Shoulder-Mounted Robot for MRI-guided arthrography: Accuracy and mounting study.

    Science.gov (United States)

    Monfaredi, R; Wilson, E; Sze, R; Sharma, K; Azizi, B; Iordachita, I; Cleary, K

    2015-08-01

    A new version of our compact and lightweight patient-mounted MRI-compatible 4 degree-of-freedom (DOF) robot for MRI-guided arthrography procedures is introduced. This robot could convert the traditional two-stage arthrography procedure (fluoroscopy-guided needle insertion followed by a diagnostic MRI scan) to a one-stage procedure, all in the MRI suite. The results of a recent accuracy study are reported. A new mounting technique is proposed and the mounting stability is investigated using optical and electromagnetic tracking on an anthropomorphic phantom. Five volunteer subjects including 2 radiologists were asked to conduct needle insertion in 4 different random positions and orientations within the robot's workspace and the displacement of the base of the robot was investigated during robot motion and needle insertion. Experimental results show that the proposed mounting method is stable and promising for clinical application.

  10. What Is Dry Eye?

    Medline Plus

    Full Text Available ... Ophthalmologists Young Ophthalmologists Tools and Services EyeCare America Help IRIS Registry Medicare Physician Payment Meetings and Deadlines ... Ophthalmologists Young Ophthalmologists Tools and Services EyeCare America Help IRIS Registry Medicare Physician Payment Meetings and Deadlines ...

  11. Eye tracking social preferences

    NARCIS (Netherlands)

    Jiang, Ting; Potters, Jan; Funaki, Yukihiko

    We hypothesize that if people are motivated by a particular social preference, then choosing in accordance with this preference will lead to an identifiable pattern of eye movements. We track eye movements while subjects make choices in simple three-person distribution experiments. We characterize

  12. XI. THE WATERING EYE

    African Journals Online (AJOL)

    cause a watering eye; this condition is.called epiphora. Clearly, then, in investigating ... blockage is a common disease in the middle age-groups seen in hospital .... a dry eye, and this is so much worse than a wet one that the procedure is only ...

  13. Dry eye syndrome

    Science.gov (United States)

    ... this page: //medlineplus.gov/ency/article/000426.htm Dry eye syndrome To use the sharing features on this page, ... second-hand smoke exposure Cold or allergy medicines Dry eye can also be caused by: Heat or ... Symptoms may include: Blurred vision Burning, itching, ...

  14. What Is Dry Eye?

    Medline Plus

    Full Text Available ... is also when your eyes do not make the right type of tears or tear film . How do tears work? When you blink, a film of tears spreads over the eye. This keeps the eye’s surface smooth and ...

  15. Photorefraction of the Eye

    Science.gov (United States)

    Colicchia, Giuseppe; Wiesner, Hartmut; Zollman, Dean

    2015-01-01

    Photorefraction is a method to easily estimate the refractive state of the eye. The principle of photorefraction involves projecting light into the eye during flash photography and then examining the paths of light that emerge from the pupil after scattering on the back portion of the interior of the eyeball (fundus). We will explain the optical…

  16. Lasik eye surgery - slideshow

    Science.gov (United States)

    ... this page: //medlineplus.gov/ency/presentations/100206.htm Lasik eye surgery - series—Normal anatomy To use the ... A.M. Editorial team. Related MedlinePlus Health Topics Laser Eye Surgery A.D.A.M., Inc. is accredited by ...

  17. About the Eye

    Medline Plus

    Full Text Available ... luh) is the small, sensitive area of the retina needed for central vision. It contains the fovea. Lens is the clear part of the eye behind the iris that helps to focus light on the retina. It allows the eye to focus on both ...

  18. LASIK Eye Surgery

    Science.gov (United States)

    ... at the front of your eye — to improve vision. Normally, images are clearly focused on the retina in the back of your eye because the ... sharply, light rays focus in front of the retina and blur distant vision. You can see objects that are close fairly ...

  19. About the Eye

    Medline Plus

    Full Text Available ... NIH), the National Eye Institute’s mission is to “conduct and support research, training, health information dissemination, and other programs with respect to blinding eye diseases, visual disorders, mechanisms of visual function, preservation of sight, and ...

  20. What Is Dry Eye?

    Medline Plus

    Full Text Available ... Services EyeCare America Help IRIS Registry Medicare Physician Payment Meetings and Deadlines Museum of Vision Ophthalmology Job ... Services EyeCare America Help IRIS Registry Medicare Physician Payment Meetings and Deadlines Museum of Vision Ophthalmology Job ...

  1. What Is Dry Eye?

    Medline Plus

    Full Text Available ... also when your eyes do not make the right type of tears or tear film . How do tears work? When you blink, a film of tears spreads over the eye. This keeps the eye’s surface smooth and clear. The tear film is important for good vision. The tear film is made of three ...

  2. What Is Dry Eye?

    Medline Plus

    Full Text Available ... Medicare Physician Payment Meetings and Deadlines Museum of Vision Ophthalmology Job Center Our Sites EyeWiki International Society ... Medicare Physician Payment Meetings and Deadlines Museum of Vision Ophthalmology Job Center Our Sites EyeWiki International Society ...

  3. Smoking and Eye Health

    Science.gov (United States)

    ... Patient Stories Español Eye Health / Tips & Prevention Sections Smoking and Eye Disease Leer en Español: El cigarrillo ... By: Brenda Pagan-Duran MD Apr. 27, 2017 Smoking contributes to a number of major health problems, ...

  4. What Is Dry Eye?

    Medline Plus

    Full Text Available ... Payment Meetings and Deadlines Museum of Vision Ophthalmology Job Center Our Sites EyeWiki International Society of Refractive ... Payment Meetings and Deadlines Museum of Vision Ophthalmology Job Center Our Sites EyeWiki International Society of Refractive ...

  5. About the Eye

    Medline Plus

    Full Text Available ... Learn how the different parts of your eye work together so you can see and make sense of the world around you. Did You Know? Vision depends on your brain as much as it does on your eyes. NEI Home Contact Us A-Z Site Map NEI on ...

  6. What Is Dry Eye?

    Medline Plus

    Full Text Available ... Media Medical Students Patients and Public Technicians and Nurses Senior Ophthalmologists Young Ophthalmologists Tools and Services EyeCare ... Media Medical Students Patients and Public Technicians and Nurses Senior Ophthalmologists Young Ophthalmologists Tools and Services EyeCare ...

  7. BullsEye

    DEFF Research Database (Denmark)

    Klokmose, Clemens Nylandsted; Kristensen, Janus Bager; Bagge, Rolf

    2014-01-01

    implemented primarily in shaders on the GPU. The techniques are realized in the BullsEye computer vision software. We demonstrate experimentally that BullsEye provides sub-pixel accuracy down to a tenth of a pixel, which is a significant improvement compared to the commonly used reacTIVision software....

  8. What Is Dry Eye?

    Medline Plus

    Full Text Available ... Young Ophthalmologists Tools and Services EyeCare America Help IRIS Registry Medicare Physician Payment Meetings and Deadlines Museum ... Young Ophthalmologists Tools and Services EyeCare America Help IRIS Registry Medicare Physician Payment Meetings and Deadlines Museum ...

  9. What Is Dry Eye?

    Medline Plus

    Full Text Available ... Senior Ophthalmologists Young Ophthalmologists Tools and Services EyeCare America Help IRIS Registry Medicare Physician Payment Meetings and ... Senior Ophthalmologists Young Ophthalmologists Tools and Services EyeCare America Help IRIS Registry Medicare Physician Payment Meetings and ...

  10. What Is Dry Eye?

    Medline Plus

    Full Text Available ... Public Technicians and Nurses Senior Ophthalmologists Young Ophthalmologists Tools and Services EyeCare America Help IRIS Registry Medicare ... Public Technicians and Nurses Senior Ophthalmologists Young Ophthalmologists Tools and Services EyeCare America Help IRIS Registry Medicare ...

  11. What Is Dry Eye?

    Medline Plus

    Full Text Available ... bloodshot when I wake up? Jun 26, 2016 Why are my eyes dry after LASIK? Jun 19, 2016 Can I be tested whether I close my eyes when I sleep? Feb 10, 2016 Can light sensitivity from Parkinson’s ...

  12. Apoptosis in the eye.

    OpenAIRE

    Chahory , Sabine; Torriglia , Alicia

    2006-01-01

    Apoptosis is a normal component of the development and health of multicellular organisms. Cells die during apoptosis in a controlled, regulated fashion. This form of cell death is very important in eye development as well as in eye pathology. We review in this chapter our current knowledge in this topic.

  13. What Is Dry Eye?

    Medline Plus

    Full Text Available ... Medical Students Patients and Public Technicians and Nurses Senior Ophthalmologists Young Ophthalmologists Tools and Services EyeCare America ... Medical Students Patients and Public Technicians and Nurses Senior Ophthalmologists Young Ophthalmologists Tools and Services EyeCare America ...

  14. Eyes, Bulging (Proptosis)

    Science.gov (United States)

    ... Early Breast Cancer to Avoid Chemo Could a Blood Test Spot Lung Cancer Early? Experimental Drug Shows 'Modest' Benefit ... often done when bulging affects only one eye. Blood tests to measure how well the thyroid is working are done when ... When bulging leads to severe dry eyes, lubrication with artificial tears is needed to ...

  15. Systems and methods for mirror mounting with minimized distortion

    Science.gov (United States)

    Antonille, Scott R. (Inventor); Wallace, Thomas E. (Inventor); Content, David A. (Inventor); Wake, Shane W. (Inventor)

    2012-01-01

    A method for mounting a mirror for use in a telescope includes attaching the mirror to a plurality of adjustable mounts; determining a distortion in the mirror caused by the plurality adjustable mounts, and, if the distortion is determined to be above a predetermined level: adjusting one or more of the adjustable mounts; and determining the distortion in the mirror caused by the adjustable mounts; and in the event the determined distortion is determined to be at or below the predetermined level, rigidizing the adjustable mounts.

  16. New Academic Partnerships in Global Health: Innovations at Mount Sinai School of Medicine

    Science.gov (United States)

    Landrigan, Philip J.; Ripp, Jonathan; Murphy, Ramon J. C.; Claudio, Luz; Jao, Jennifer; Hexom, Braden; Bloom, Harrison G.; Shirazian, Taraneh; Elahi, Ebby; Koplan, Jeffrey P.

    2011-01-01

    Global health has become an increasingly important focus of education, research, and clinical service in North American universities and academic health centers. Today there are at least 49 academically based global health programs in the United States and Canada, as compared with only one in 1999. A new academic society, the Consortium of Universities for Global Health, was established in 2008 and has grown significantly. This sharp expansion reflects convergence of 3 factors: (1) rapidly growing student and faculty interest in global health; (2) growing realization–powerfully catalyzed by the acquired immune deficiency syndrome epidemic, the emergence of other new infections, climate change, and globalization–that health problems are interconnected, cross national borders, and are global in nature; and (3) rapid expansion in resources for global health. This article examines the evolution of the concept of global health and describes the driving forces that have accelerated interest in the field. It traces the development of global health programs in academic health centers in the United States. It presents a blueprint for a new school-wide global health program at Mount Sinai School of Medicine. The mission of that program, Mount Sinai Global Health, is to enhance global health as an academic field of study within the Mount Sinai community and to improve the health of people around the world. Mount Sinai Global Health is uniting and building synergies among strong, existing global health programs within Mount Sinai; it is training the next generation of physicians and health scientists to be leaders in global health; it is making novel discoveries that translate into blueprints for improving health worldwide; and it builds on Mount Sinai’s long and proud tradition of providing medical and surgical care in places where need is great and resources few. PMID:21598272

  17. The research on a novel type of the solar-blind UV head-mounted displays

    Science.gov (United States)

    Zhao, Shun-long

    2011-08-01

    Ultraviolet technology of detecting is playing a more and more important role in the field of civil application, especially in the corona discharge detection, in modern society. Now the UV imaging detector is one of the most important equipments in power equipment flaws detection. And the modern head-mounted displays (HMDs) have shown the applications in the fields of military, industry production, medical treatment, entertainment, 3D visualization, education and training. We applied the system of head-mounted displays to the UV image detection, and a novel type of head-mounted displays is presented: the solar-blind UV head-mounted displays. And the structure is given. By the solar-blind UV head-mounted displays, a real-time, isometric and visible image of the corona discharge is correctly displayed upon the background scene where it exists. The user will see the visible image of the corona discharge on the real scene rather than on a small screen. Then the user can easily find out the power equipment flaws and repair them. Compared with the traditional UV imaging detector, the introducing of the HMDs simplifies the structure of the whole system. The original visible spectrum optical system is replaced by the eye in the solar-blind UV head-mounted displays. And the optical image fusion technology would be used rather than the digital image fusion system which is necessary in traditional UV imaging detector. That means the visible spectrum optical system and digital image fusion system are not necessary. This makes the whole system cheaper than the traditional UV imaging detector. Another advantage of the solar-blind UV head-mounted displays is that the two hands of user will be free. So while observing the corona discharge the user can do some things about it. Therefore the solar-blind UV head-mounted displays can make the corona discharge expose itself to the user in a better way, and it will play an important role in corona detection in the future.

  18. Increased earthquake safety through optimised mounting concept

    International Nuclear Information System (INIS)

    Kollmann, Dieter; Senechal, Holger

    2013-01-01

    Since Fukushima, there has been intensive work on earthquake safety in all nuclear power plants. A large part of these efforts aim at the earthquake safety of safety-relevant pipeline systems. The problem with earthquake safety here is not the pipeline system itself but rather its mountings and connections to components. This is precisely the topic that the KAE dealt with in years of research and development work. It has developed an algorithm that determines the optimal mounting concept with a few iteration steps depending on arbitrary combinations of loading conditions whilst maintaining compliance with relevant regulations for any pipeline systems. With this tool at hand, we are now in a position to plan and realise remedial measures accurately with minimum time and hardware expenditure, and so distinctly improve the earthquake safety of safety-relevant systems. (orig.)

  19. Micro-inverter solar panel mounting

    Science.gov (United States)

    Morris, John; Gilchrist, Phillip Charles

    2016-02-02

    Processes, systems, devices, and articles of manufacture are provided. Each may include adapting micro-inverters initially configured for frame-mounting to mounting on a frameless solar panel. This securement may include using an adaptive clamp or several adaptive clamps secured to a micro-inverter or its components, and using compressive forces applied directly to the solar panel to secure the adaptive clamp and the components to the solar panel. The clamps can also include compressive spacers and safeties for managing the compressive forces exerted on the solar panels. Friction zones may also be used for managing slipping between the clamp and the solar panel during or after installation. Adjustments to the clamps may be carried out through various means and by changing the physical size of the clamps themselves.

  20. Mapping the Spread of Mounted Warfare

    Directory of Open Access Journals (Sweden)

    Peter Turchin

    2016-12-01

    Full Text Available Military technology is one of the most important factors affecting the evolution of complex societies. In particular, mounted warfare, the use of horse-riders in military operations, revolutionized war as it spread to different parts of Eurasia and Africa during the Ancient and Medieval eras, and to the Americas during the Early Modern period. Here we use a variety of sources to map this spread.

  1. New mounting improves solar-cell efficiency

    Science.gov (United States)

    Shepard, N. F., Jr.

    1980-01-01

    Method boosts output by about 20 percent by trapping and redirecting solar radiation without increasing module depth. Mounted solar-cell array is covered with internally reflecting plate. Plate is attached to each cell by transparent adhesive, and space between cells is covered with layer of diffusely reflecting material. Solar energy falling on space between cells is diffused and reflected internally by plate until it is reflected onto solar cell.

  2. Customer Satisfaction Level in Mount Sherpa Restaurant

    OpenAIRE

    Shrestha, Sameer

    2015-01-01

    Customer satisfaction is the key to every successful business in the sense of profit motive, as well as in the long run. It is the desire of every business to be able to understand their customers’ need. Many businesses, especially related with the service industry, carry out different surveys and conduct research in order to know what their customers really want. This research was carried out to measure the customer satisfaction level in Mount Sherpa restaurant. The results and findings ...

  3. Conceptual design for PSP mounting bracket

    Energy Technology Data Exchange (ETDEWEB)

    Ransom, G.; Stein, R. [Martin Marietta Energy Systems, Inc., Piketon, OH (United States)

    1991-12-31

    Protective structural packages (PSP`s or overpacks) used to ship 2 1/2-ton UF{sub 6} product cylinders are bolted to truck trailers. All bolts penetrate two longitudinal rows of wooden planks. Removal and replacement is required at various intervals for maintenance and routine testing. A conceptual design is presented for mounting brackets which would securely attach PSP`s to trailer frames, reduce removal and replacement time, and minimize risk of personnel injury.

  4. Registration of an on-axis see-through head-mounted display and camera system

    Science.gov (United States)

    Luo, Gang; Rensing, Noa M.; Weststrate, Evan; Peli, Eli

    2005-02-01

    An optical see-through head-mounted display (HMD) system integrating a miniature camera that is aligned with the user's pupil is developed and tested. Such an HMD system has a potential value in many augmented reality applications, in which registration of the virtual display to the real scene is one of the critical aspects. The camera alignment to the user's pupil results in a simple yet accurate calibration and a low registration error across a wide range of depth. In reality, a small camera-eye misalignment may still occur in such a system due to the inevitable variations of HMD wearing position with respect to the eye. The effects of such errors are measured. Calculation further shows that the registration error as a function of viewing distance behaves nearly the same for different virtual image distances, except for a shift. The impact of prismatic effect of the display lens on registration is also discussed.

  5. Advocacy for eye care

    Directory of Open Access Journals (Sweden)

    Thulasiraj D Ravilla

    2012-01-01

    Full Text Available The effectiveness of eye care service delivery is often dependant on how the different stakeholders are aligned. These stakeholders range from the ministries of health who have the capacity to grant government subsidies for eye care, down to the primary healthcare workers who can be enrolled to screen for basic eye diseases. Advocacy is a tool that can help service providers draw the attention of key stakeholders to a particular area of concern. By enlisting the support, endorsement and participation of a wider circle of players, advocacy can help to improve the penetration and effectiveness of the services provided. There are several factors in the external environmental that influence the eye care services - such as the availability of trained manpower, supply of eye care consumables, government rules and regulations. There are several instances where successful advocacy has helped to create an enabling environment for eye care service delivery. Providing eye care services in developing countries requires the support - either for direct patient care or for support services such as producing trained manpower or for research and dissemination. Such support, in the form of financial or other resources, can be garnered through advocacy.

  6. Aquaporins in the Eye

    DEFF Research Database (Denmark)

    Tran, Thuy Linh; Hamann, Steffen; Heegaard, Steffen

    2017-01-01

    The major part of the eye consists of water . Continuous movement of water and ions between the ocular compartments and to the systemic circulation is pivotal for many physiological functions in the eye. The movement of water facilitates removal of the many metabolic products of corneal-, ciliary...... pressure. In the retina, water is transported into the vitreous body and across the retinal pigment epithelium to regulate the extracellular environment and the hydration of the retina. Aquaporins (AQPs ) take part in the water transport throughout the eye....

  7. Mounting apparatus for a nozzle guide vane assembly

    Science.gov (United States)

    Boyd, Gary L.; Shaffer, James E.

    1995-01-01

    The present invention provides a ceramic nozzle guide assembly with an apparatus for mounting it to a metal nozzle case that includes an intermediate ceramic mounting ring. The mounting ring includes a plurality of projections that are received within a plurality of receptacles formed in the nozzle case. The projections of the mounting ring are secured within the receptacles by a ceramic retainer that allows contact between the two components only along arcuate surfaces thus eliminating sliding contact between the components.

  8. 46 CFR 61.05-15 - Boiler mountings and attachments.

    Science.gov (United States)

    2010-10-01

    ... 46 Shipping 2 2010-10-01 2010-10-01 false Boiler mountings and attachments. 61.05-15 Section 61.05... TESTS AND INSPECTIONS Tests and Inspections of Boilers § 61.05-15 Boiler mountings and attachments. (a....05-10. (b) Each stud or bolt for each boiler mounting that paragraph (c) of this section requires to...

  9. Organization and processes of the BN-600 reactor mounting

    International Nuclear Information System (INIS)

    Dubrovin, E.Z.; Karpenko, V.N.; Takhtaulov, V.M.

    1982-01-01

    Structural peculiarities of the BN-600 reactor plant are considered. Experience of metal structure mounting inside the reactor vessel has been analysed. Recommendations on the improvements on the organization of the thermal mechanical equipment mounting are given. It is concluded that the consideration of these recommendations will permit to reduce expenditures of labour by 10-40% for the mounting

  10. [The controversy of routine articulator mounting in orthodontics].

    Science.gov (United States)

    Wang, Li; Han, Xianglong; Bai, Ding

    2013-06-01

    Articulators have been widely used by clinicians of dentistry. But routine articulator mounting is still controversial in orthodontics. Orthodontists oriented by gnathology approve routine articulator mounting while nongnathologic orthodontists disapprove it. This article reviews the thoughts of orthodontist that they agree or disagree with routine articulator mounting based on the considerations of biting, temporomandibular disorder (TMD), periodontitis, and so on.

  11. 49 CFR 571.212 - Standard No. 212; Windshield mounting.

    Science.gov (United States)

    2010-10-01

    ... 49 Transportation 6 2010-10-01 2010-10-01 false Standard No. 212; Windshield mounting. 571.212... Motor Vehicle Safety Standards § 571.212 Standard No. 212; Windshield mounting. S1. Scope. This standard..., under the conditions of S6, the windshield mounting of the vehicle shall retain not less than the...

  12. Eye Carduino: A Car Control System using Eye Movements

    Science.gov (United States)

    Kumar, Arjun; Nagaraj, Disha; Louzardo, Joel; Hegde, Rajeshwari

    2011-12-01

    Modern automotive systems are rapidly becoming highly of transportation, but can be a web integrated media centre. This paper explains the implementation of a vehicle control defined and characterized by embedded electronics and software. With new technologies, the vehicle industry is facing new opportunities and also new challenges. Electronics have improved the performance of vehicles and at the same time, new more complex applications are introduced. Examples of high level applications include adaptive cruise control and electronic stability programs (ESP). Further, a modern vehicle does not have to be merely a means using only eye movements. The EyeWriter's native hardware and software work to return the co-ordinates of where the user is looking. These co-ordinates are then used to control the car. A centre-point is defined on the screen. The higher on the screen the user's gaze is, the faster the car will accelerate. Braking is done by looking below centre. Steering is done by looking left and right on the screen.

  13. About the Eye

    Medline Plus

    Full Text Available ... programs with respect to blinding eye diseases, visual disorders, mechanisms of visual function, preservation of sight, and the special health problems and ... It sends electrical impulses through the optic nerve to the brain. Watch ...

  14. Diabetic Eye Problems

    Science.gov (United States)

    ... damage your eyes. The most common problem is diabetic retinopathy. It is a leading cause of blindness ... You need a healthy retina to see clearly. Diabetic retinopathy damages the tiny blood vessels inside your ...

  15. About the Eye

    Medline Plus

    Full Text Available ... of many different parts that work together to help you see. Check out the diagrams below to ... part of the eye behind the iris that helps to focus light on the retina. It allows ...

  16. About the Eye

    Medline Plus

    Full Text Available ... to blinding eye diseases, visual disorders, mechanisms of visual function, preservation of sight, and the special health problems and requirements of the blind.” ... Clinical Studies Publications Catalog Photos ...

  17. About the Eye

    Medline Plus

    Full Text Available ... Stuff Cool Eye Tricks Links to More Information Optical Illusions Printables ... Optic nerve (OP-tic nurv) is the bundle of more than 1 million nerve fibers that carry visual messages from the retina to ...

  18. What Is Dry Eye?

    Medline Plus

    Full Text Available ... month dissolvable punctal plug be removed or pushed down the tear duct to insert a permanent punctal ... Your Eyelid Nov 29, 2017 New Dry Eye Treatment is a Tear-Jerker Jul 21, 2017 Three ...

  19. About the Eye

    Medline Plus

    Full Text Available ... the Scientific Director Office of the Clinical Director Laboratories, Sections and Units Division of Epidemiology and Clinical ... System Your Eyes’ Natural Defenses Eye Health and Safety First Aid Tips Healthy Vision Tips Protective Eyewear ...

  20. Eye Involvement in TSC

    Science.gov (United States)

    ... 50% of the individuals with TSC have normal intelligence, and inasmuch as these individuals may become parents, ... of vision may be difficult or impossible. Since growth and change of TSC lesions in the eye ...

  1. What Is Dry Eye?

    Medline Plus

    Full Text Available ... EyeCare America Help IRIS Registry Medicare Physician Payment Meetings and Deadlines Museum of Vision Ophthalmology Job Center ... Ophthalmology Guide Find an Ophthalmologist Advanced Search Annual Meeting Clinical Education Practice Management Member Services Advocacy Foundation ...

  2. About the Eye

    Medline Plus

    Full Text Available ... Units Division of Epidemiology and Clinical Applications eyeGENE Research Directors Office Office of the Scientific Director Sheldon S. ... Fellowships NEI Summer Intern Program Diversity In Vision Research & Ophthalmology (DIVRO) Student Training Programs To search for ...

  3. Amblyopia: Lazy Eye Treatment

    Science.gov (United States)

    ... with Myopia Aug 31, 2017 Eye Injuries from Laundry Packets On the Rise Jun 30, 2017 Combating ... with Industry Medical Disclaimer Privacy Policy Terms of Service For Advertisers For Media Ophthalmology Job Center © American ...

  4. Amblyopia: Lazy Eye Diagnosis

    Science.gov (United States)

    ... with Myopia Aug 31, 2017 Eye Injuries from Laundry Packets On the Rise Jun 30, 2017 Combating ... with Industry Medical Disclaimer Privacy Policy Terms of Service For Advertisers For Media Ophthalmology Job Center © American ...

  5. What Is Dry Eye?

    Medline Plus

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  14. About the Eye

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    Full Text Available ... about each part of your eye and what it does. Macula (MACK-yoo-luh) is the small, ... area of the retina needed for central vision. It contains the fovea. Lens is the clear part ...

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  18. Using Eye Makeup

    Science.gov (United States)

    ... harmful chemicals. Before applying makeup, be sure your face and eyelids are very clean. Always apply makeup outside the lash line, away from the eye, to avoid blocking the oil glands of the upper or lower ...

  19. About the Eye

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  20. About the Eye

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  1. About the Eye

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    Full Text Available ... part of your eye and what it does. Macula (MACK-yoo-luh) is the small, sensitive area ... FOH-vee-uh) is the center of the macula, where your vision is sharpest. Optic nerve (OP- ...

  2. What Is Dry Eye?

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  4. Eye and orbit ultrasound

    Science.gov (United States)

    ... Images Head and eye echoencephalogram References Coleman DJ, Silverman RH, Lloyd HO, Daly S. Evaluation of the posterior ... Vision Institute, La Jolla, CA. Also reviewed by David Zieve, MD, MHA, Medical Director, Brenda Conaway, Editorial ...

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    Full Text Available ... System Your Eyes’ Natural Defenses Eye Health and Safety First Aid Tips Healthy Vision Tips Protective Eyewear ... Social Media Policies and Other Important Links NEI Employee Emergency Information NEI Intranet (Employees Only) *PDF files ...

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  13. Eye Injuries at Home

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    ... by the Numbers — Infographic Five Steps to Safer Champagne Celebrations Eye Injuries at Home Leer en Español: ... that can splatter hot grease or oil. Opening champagne bottles during a celebration. Drilling or hammering screws ...

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  17. Fish eye optics

    Czech Academy of Sciences Publication Activity Database

    Hudec, René; Michalová, S.

    2017-01-01

    Roč. 47, č. 2 (2017), s. 94-99 ISSN 1335-1842. [INTEGRAL/BART Workshop /14./. Karlovy Vary, 03.04.2017-07.04.2017] Grant - others:GA ČR(CZ) GA13-33324S Institutional support: RVO:67985815 Keywords : fish eye optics * lobster eye optics * X-ray monitoring Subject RIV: BN - Astronomy, Celestial Mechanics, Astrophysics OBOR OECD: Astronomy (including astrophysics,space science) Impact factor: 0.336, year: 2016

  18. Combat vehicle crew helmet-mounted display: next generation high-resolution head-mounted display

    Science.gov (United States)

    Nelson, Scott A.

    1994-06-01

    The Combat Vehicle Crew Head-Mounted Display (CVC HMD) program is an ARPA-funded, US Army Natick Research, Development, and Engineering Center monitored effort to develop a high resolution, flat panel HMD for the M1 A2 Abrams main battle tank. CVC HMD is part of the ARPA High Definition Systems (HDS) thrust to develop and integrate small (24 micrometers square pels), high resolution (1280 X 1024 X 6-bit grey scale at 60 frame/sec) active matrix electroluminescent (AMEL) and active matrix liquid crystal displays (AMLCD) for head mounted and projection applications. The Honeywell designed CVC HMD is a next generation head-mounted display system that includes advanced flat panel image sources, advanced digital display driver electronics, high speed (> 1 Gbps) digital interconnect electronics, and light weight, high performance optical and mechanical designs. The resulting dramatic improvements in size, weight, power, and cost have already led to program spin offs for both military and commercial applications.

  19. Danish Rural Eye Study

    DEFF Research Database (Denmark)

    Høeg, Tracy Beth; Ellervik, Christina; Buch, Helena

    2016-01-01

    , Danish Rural Eye Study (DRES). All DRES participants received a comprehensive general health examination preceding their eye examination, including measurement of best-corrected visual acuity (BCVA) for each eye, bilateral 45° retinal fundus photographs and further ophthalmological examination where...... indicated. RESULTS: Overall, 3826 of 3843 participants (99.6%) had bilateral visual acuity measurements. The overall frequency of VI (BCVA eye) was 0.4% (95% confidence interval, CI, 0.2-0.7%; n = 15) among all DRES participants, 0.6% (95% CI 0.3-1.0%; n = 15) among participants...... >50 years and 3.7% (95% CI 2.1-6.5%; n = 11) in participants >80 years. The primary causes of VI in the better-seeing eye were age-related macular degeneration (AMD) in 46.7% (7/15) and cataract in 26.7% (4/15). A total of 43.3% (n = 115) of participants >80 years were pseudophakic in one or both eyes...

  20. ATST telescope mount: telescope of machine tool

    Science.gov (United States)

    Jeffers, Paul; Stolz, Günter; Bonomi, Giovanni; Dreyer, Oliver; Kärcher, Hans

    2012-09-01

    The Advanced Technology Solar Telescope (ATST) will be the largest solar telescope in the world, and will be able to provide the sharpest views ever taken of the solar surface. The telescope has a 4m aperture primary mirror, however due to the off axis nature of the optical layout, the telescope mount has proportions similar to an 8 meter class telescope. The technology normally used in this class of telescope is well understood in the telescope community and has been successfully implemented in numerous projects. The world of large machine tools has developed in a separate realm with similar levels of performance requirement but different boundary conditions. In addition the competitive nature of private industry has encouraged development and usage of more cost effective solutions both in initial capital cost and thru-life operating cost. Telescope mounts move relatively slowly with requirements for high stability under external environmental influences such as wind buffeting. Large machine tools operate under high speed requirements coupled with high application of force through the machine but with little or no external environmental influences. The benefits of these parallel development paths and the ATST system requirements are being combined in the ATST Telescope Mount Assembly (TMA). The process of balancing the system requirements with new technologies is based on the experience of the ATST project team, Ingersoll Machine Tools who are the main contractor for the TMA and MT Mechatronics who are their design subcontractors. This paper highlights a number of these proven technologies from the commercially driven machine tool world that are being introduced to the TMA design. Also the challenges of integrating and ensuring that the differences in application requirements are accounted for in the design are discussed.

  1. A trolley mounted magazine for reactor maintenance

    Energy Technology Data Exchange (ETDEWEB)

    Brennan, P.J.; Madani, M.; Ridgway, G.H. [GE Hitachi Nuclear Energy Canada, Peterborough, Ontario (Canada)], E-mail: patrick1.brennan@ge.com, mehdi.madani@ge.com, guy.ridgway@ge.com; Lundy, E.; Knight, D. [IM and CS (Inspection, Maintenance and Commerical Services), Ontario Power Generation, Ajax, Ontario (Canada)], E-mail: erroll.lundy@opg.com, david.knight@opg.com

    2009-03-15

    This paper describes the design of a mechanism incorporating a rotary magazine to be mounted on a fuelling machine transport trolley for use at a Darlington reactor during a feeder replacement or maintenance outage. The magazine stores reactor channel maintenance components, such as channel isolation plugs and vented closure plugs, in twelve available magazine channels. Use of the magazine rather than a fuelling machine reduces the time required to transfer such components between the Central Service Area and reactor channels. Component transfers are accomplished by locking the fuelling machine onto one of the magazine channels and using a local controller to execute commands received from the fuel handling control system. (author)

  2. A trolley mounted magazine for reactor maintenance

    Energy Technology Data Exchange (ETDEWEB)

    Brennan, P.J.; Madani, M.; Ridgway, G.H., E-mail: patrick1.brennan@ge.com, E-mail: mehdi.madani@ge.com, E-mail: guy.ridgway@ge.com [GE Hitachi Nuclear Energy Canada, Peterborough, Ontario (Canada); Lundy, E.; Knight, D., E-mail: erroll.lundy@opg.com, E-mail: david.knight@opg.com [Ontario Power Generation, Inspection, Maintenance and Commercial Services, Ajax, Ontario (Canada)

    2008-07-01

    This paper describes the design of a mechanism incorporating a rotary magazine to be mounted on a fuelling machine transport trolley for use at a Darlington reactor during a feeder replacement or maintenance outage. The magazine stores reactor channel maintenance components, such as channel isolation plugs and vented closure plugs, in twelve available magazine channels. Use of the magazine rather than a fuelling machine reduces the time required to transfer such components between the Central Service Area and reactor channels. Component transfers are accomplished by locking the fuelling machine onto one of the magazine channels and using a local controller to execute commands received from the fuel handling control system. (author)

  3. A trolley mounted magazine for reactor maintenance

    International Nuclear Information System (INIS)

    Brennan, P.J.; Madani, M.; Ridgway, G.H.; Lundy, E.; Knight, D.

    2009-01-01

    This paper describes the design of a mechanism incorporating a rotary magazine to be mounted on a fuelling machine transport trolley for use at a Darlington reactor during a feeder replacement or maintenance outage. The magazine stores reactor channel maintenance components, such as channel isolation plugs and vented closure plugs, in twelve available magazine channels. Use of the magazine rather than a fuelling machine reduces the time required to transfer such components between the Central Service Area and reactor channels. Component transfers are accomplished by locking the fuelling machine onto one of the magazine channels and using a local controller to execute commands received from the fuel handling control system. (author)

  4. Mount Zirkel Wilderness and vicinity, Colorado

    International Nuclear Information System (INIS)

    Snyder, G.L.; Patten, L.L.

    1984-01-01

    Several areas of metallic and nonmetallic mineralization have been identified from surface occurrences within the Mount Zirkel Wilderness and vicinity, Colorado. Three areas of probable copper-lead-zinc-silver-gold resource potential, two areas of probable chrome-platinum resource potential, four areas of probable uranium-thorium resource potential, two areas of probable molybdenum resource potential, and one area of probable fluorspar potential were identified by studies in 1965-1973 by the USGS and USBM. No potential for fossil fuel or geothermal resources was identified

  5. A trolley mounted magazine for reactor maintenance

    International Nuclear Information System (INIS)

    Brennan, P.J.; Madani, M.; Ridgway, G.H.; Lundy, E.; Knight, D.

    2008-01-01

    This paper describes the design of a mechanism incorporating a rotary magazine to be mounted on a fuelling machine transport trolley for use at a Darlington reactor during a feeder replacement or maintenance outage. The magazine stores reactor channel maintenance components, such as channel isolation plugs and vented closure plugs, in twelve available magazine channels. Use of the magazine rather than a fuelling machine reduces the time required to transfer such components between the Central Service Area and reactor channels. Component transfers are accomplished by locking the fuelling machine onto one of the magazine channels and using a local controller to execute commands received from the fuel handling control system. (author)

  6. Cotton phenotyping with lidar from a track-mounted platform

    Science.gov (United States)

    French, Andrew N.; Gore, Michael A.; Thompson, Alison

    2016-05-01

    High-Throughput Phenotyping (HTP) is a discipline for rapidly identifying plant architectural and physiological responses to environmental factors such as heat and water stress. Experiments conducted since 2010 at Maricopa, Arizona with a three-fold sensor group, including thermal infrared radiometers, active visible/near infrared reflectance sensors, and acoustic plant height sensors, have shown the validity of HTP with a tractor-based system. However, results from these experiments also show that accuracy of plant phenotyping is limited by the system's inability to discriminate plant components and their local environmental conditions. This limitation may be overcome with plant imaging and laser scanning which can help map details in plant architecture and sunlit/shaded leaves. To test the capability for mapping cotton plants with a laser system, a track-mounted platform was deployed in 2015 over a full canopy and defoliated cotton crop consisting of a scanning LIDAR driven by Arduinocontrolled stepper motors. Using custom Python and Tkinter code, the platform moved autonomously along a pipe-track at 0.1 m/s while collecting LIDAR scans at 25 Hz (0.1667 deg. beam). These tests showed that an autonomous LIDAR platform can reduce HTP logistical problems and provide the capability to accurately map cotton plants and cotton bolls. A prototype track-mounted platform was developed to test the use of LIDAR scanning for High- Throughput Phenotyping (HTP). The platform was deployed in 2015 at Maricopa, Arizona over a senescent cotton crop. Using custom Python and Tkinter code, the platform moved autonomously along a pipe-track at cotton bolls.

  7. Research on Measurement Accuracy of Laser Tracking System Based on Spherical Mirror with Rotation Errors of Gimbal Mount Axes

    Science.gov (United States)

    Shi, Zhaoyao; Song, Huixu; Chen, Hongfang; Sun, Yanqiang

    2018-02-01

    This paper presents a novel experimental approach for confirming that spherical mirror of a laser tracking system can reduce the influences of rotation errors of gimbal mount axes on the measurement accuracy. By simplifying the optical system model of laser tracking system based on spherical mirror, we can easily extract the laser ranging measurement error caused by rotation errors of gimbal mount axes with the positions of spherical mirror, biconvex lens, cat's eye reflector, and measuring beam. The motions of polarization beam splitter and biconvex lens along the optical axis and vertical direction of optical axis are driven by error motions of gimbal mount axes. In order to simplify the experimental process, the motion of biconvex lens is substituted by the motion of spherical mirror according to the principle of relative motion. The laser ranging measurement error caused by the rotation errors of gimbal mount axes could be recorded in the readings of laser interferometer. The experimental results showed that the laser ranging measurement error caused by rotation errors was less than 0.1 μm if radial error motion and axial error motion were within ±10 μm. The experimental method simplified the experimental procedure and the spherical mirror could reduce the influences of rotation errors of gimbal mount axes on the measurement accuracy of the laser tracking system.

  8. Pink Eye: What To Do

    Centers for Disease Control (CDC) Podcasts

    In this podcast, CDC's Adam Cohen, MD, a pediatrician and parent, discusses conjunctivitis (pink eye), a common eye condition in children and adults. He reviews pink eye causes and treatment, suggestions on when to call or visit a doctor, and practical tips to prevent pink eye from spreading.

  9. Prediction of Human Eye Fixations using Symmetry

    OpenAIRE

    Kootstra, Gert; Schomaker, Lambert R. B.

    2009-01-01

    Humans are very sensitive to symmetry in visual patterns. Reaction time experiments show that symmetry is detected and recognized very rapidly. This suggests that symmetry is a highly salient feature. Existing computational models of saliency, however, have mainly focused on contrast as a measure of saliency. In this paper, we discuss local symmetry as a measure of saliency. We propose a number of symmetry models and perform an eye-tracking study with human participants viewing photographic i...

  10. Hybrid diffractive-refractive optical system design of head-mounted display for augmented reality

    Science.gov (United States)

    Zhang, Huijuan

    2005-02-01

    An optical see-through head-mounted display for augmented reality is designed in this paper. Considering the factors, such as the optical performance, the utilization ratios of energy of real world and virtual world, the feelings of users when he wears it and etc., a structure of the optical see-through is adopted. With the characteristics of the particular negative dispersive and the power of realizing random-phase modulation, the diffractive surface is helpful for optical system of reducing weight, simplifying structure and etc., and a diffractive surface is introduced in our optical system. The optical system with 25 mm eye relief, 12 mm exit pupil and 20° (H)x15.4° (V) field-of-view is designed. The utilization ratios of energy of real world and virtual world are 1/4 and 1/2, respectively. The angular resolution of display is 0.27 mrad and it less than that of the minimum of human eyes. The diameter of this system is less than 46mm, and it applies the binocular. This diffractive-refractive optical system of see-through head-mounted display not only satisfies the demands of user"s factors in structure, but also with high resolution, very small chromatic aberration and distortion, and satisfies the need of augmented reality. In the end, the parameters of the diffractive surface are discussed.

  11. Research on LQR optimal control method of active engine mount

    Science.gov (United States)

    Huan, Xie; Yu, Duan

    2018-04-01

    In this paper, the LQR control method is applied to the active mount of the engine, and a six-cylinder engine excitation model is established. Through the joint simulation of AMESim and MATLAB, the vibration isolation performance of the active mount system and the passive mount system is analyzed. Excited by the multi-engine operation, the simulation results of the vertical displacement, acceleration and dynamic deflection of the vehicle body show that the vibration isolation capability of the active mount system is superior to that of the passive mount system. It shows that compared with the passive mount, LQR active mount can greatly improve the vibration isolation performance, which proves the feasibility and effectiveness of the LQR control method.

  12. Cross-axis adaptation improves 3D vestibulo-ocular reflex alignment during chronic stimulation via a head-mounted multichannel vestibular prosthesis

    Science.gov (United States)

    Dai, Chenkai; Fridman, Gene Y.; Chiang, Bryce; Davidovics, Natan; Melvin, Thuy-Anh; Cullen, Kathleen E.; Della Santina, Charles C.

    2012-01-01

    By sensing three-dimensional (3D) head rotation and electrically stimulating the three ampullary branches of a vestibular nerve to encode head angular velocity, a multichannel vestibular prosthesis (MVP) can restore vestibular sensation to individuals disabled by loss of vestibular hair cell function. However, current spread to afferent fibers innervating non-targeted canals and otolith endorgans can distort the vestibular nerve activation pattern, causing misalignment between the perceived and actual axis of head rotation. We hypothesized that over time, central neural mechanisms can adapt to correct this misalignment. To test this, we rendered five chinchillas vestibular-deficient via bilateral gentamicin treatment and unilaterally implanted them with a head mounted MVP. Comparison of 3D angular vestibulo-ocular reflex (aVOR) responses during 2 Hz, 50°/s peak horizontal sinusoidal head rotations in darkness on the first, third and seventh days of continual MVP use revealed that eye responses about the intended axis remained stable (at about 70% of the normal gain) while misalignment improved significantly by the end of one week of prosthetic stimulation. A comparable time course of improvement was also observed for head rotations about the other two semicircular canal axes and at every stimulus frequency examined (0.2–5 Hz). In addition, the extent of disconjugacy between the two eyes progressively improved during the same time window. These results indicate that the central nervous system rapidly adapts to multichannel prosthetic vestibular stimulation to markedly improve 3D aVOR alignment within the first week after activation. Similar adaptive improvements are likely to occur in other species, including humans. PMID:21374081

  13. A novel approach to patient self-monitoring of sonographic examinations using a head-mounted display.

    Science.gov (United States)

    Inoue, Masaharu; Kihara, Kazunori; Yoshida, Soichiro; Ito, Masaya; Takeshita, Hideki; Ishioka, Junichiro; Matsuoka, Yoh; Numao, Noboru; Saito, Kazutaka; Fujii, Yasuhisa

    2015-01-01

    Patients' use of a head-mounted display during their sonographic examinations could provide them with information about their diseases in real time and might help improve "patient-centered care." We conducted this prospective study to evaluate the feasibility of a modern head-mounted display for patient self-monitoring of sonographic examinations. In November and December 2013, 58 patients were enrolled. Patients wore a head-mounted display (HMZ-T2; Sony Corporation, Tokyo, Japan) during their sonographic examinations and watched their own images in real time. After the sonographic examinations, the patients completed a questionnaire, in which they evaluated the utility of the head-mounted display, their understanding of their diseases, their satisfaction with using the head-mounted display, and any adverse events. Until November 26, 2013, patients' names were requested on the questionnaire; after that date, the questionnaire was changed to be anonymous. Of the 58 patients, 56 (97%) elected to participate in this study. The head-mounted display was reported to have good image quality by 42 patients (75%) and good wearability by 39 (70%). Thirty-six patients (64%) reported they had deepened their understanding of their diseases. There were no major complications, and only 2 patients (4%) had mild eye fatigue. There was no significant association between questionnaire results and patient characteristics. None of the questionnaire results changed significantly after the questionnaire was made anonymous. The use of a modern head-mounted display by patients during sonographic examinations provided good image quality with acceptable wearability. It could deepen their understanding of their diseases and help develop patient-centered care. © 2015 by the American Institute of Ultrasound in Medicine.

  14. Evaluation of shear mounted elastomeric damper

    Science.gov (United States)

    Zorzi, E.; Walton, J.

    1982-01-01

    Viton-70 elastomeric shear mounted damper was built and tested on a T-55 power turbine spool in the rotor's high speed balancing rig. This application of a shear mounted elastomeric damper demonstrated for the first time, the feasibility of using elastomers as the primary rotor damping source in production turbine engine hardware. The shear damper design was selected because it was compatible with actual gas turbine engine radial space constraints, could accommodate both the radial and axial thrust loads present in gas turbine engines, and was capable of controlled axial preload. The shear damper was interchangeable with the production T-55 power turbine roller bearing support so that a direct comparison between the shear damper and the production support structure could be made. Test results show that the Viton-70 elastomer damper operated successfully and provided excellent control of both synchronous and nonsynchronous vibrations through all phases of testing up to the maximum rotor speed of 16,000 rpm. Excellent correlation between the predicted and experienced critical speeds, mode shapes and log decrements for the power turbine rotor and elastomer damper assembly was also achieved.

  15. Experience with HEP analysis on mounted filesystems

    International Nuclear Information System (INIS)

    Fuhrmann, Patrick; Gasthuber, Martin; Kemp, Yves; Ozerov, Dmitry

    2012-01-01

    We present results on different approaches on mounted filesystems in use or under investigation at DESY. dCache, established since long as a storage system for physics data has implemented the NFS v4.1/pNFS protocol. New performance results will be shown with the most current version of the dCache server. In addition to the native usage of the mounted filesystem in a LAN environment, the results are given for the performance of the dCache NFS v4.1/pNFS in WAN case. Several commercial vendors are currently in alpha or beta phase of adding the NFS v4.1/pNFS protocol to their storage appliances. We will test some of these vendor solutions for their readiness for HEP analysis. DESY has recently purchased an IBM Sonas system. We will present the result of a thorough performance evaluation using the native protocols NFS (v3 or v4) and GPFS. As the emphasis is on the usability for end user analysis, we will use latest ROOT versions and current end user analysis code for benchmark scenarios.

  16. A head-mounted display system for augmented reality: Initial evaluation for interventional MRI

    International Nuclear Information System (INIS)

    Wendt, M.; Wacker, F.K.

    2003-01-01

    Purpose: To discuss the technical details of a head mounted display with an augmented reality (AR) system and to describe a first pre-clinical evaluation in interventional MRI. Method: The AR system consists of a video-see-through head mounted display (HMD), mounted with a mini video camera for tracking and a stereo pair of mini cameras that capture live images of the scene. The live video view of the phantom/patient is augmented with graphical representations of anatomical structures from MRI image data and is displayed on the HMD. The application of the AR system with interventional MRI was tested using a MRI data set of the head and a head phantom. Results: The HMD enables the user to move around and observe the scene dynamically from various viewpoints. Within a short time the natural hand-eye coordination can easily be adapted to the slightly different view. The 3D perception is based on stereo and kinetic depth cues. A circular target with a diameter of 0.5 square centimeter was hit in 19 of 20 attempts. In a first evaluation the MRI image data augmented reality scene of a head phantom allowed good planning and precise simulation of a puncture. Conclusion: The HMD in combination with AR provides a direct, intuitive guidance for interventional MR procedures. (orig.) [de

  17. NASA's "Eyes" Focus on Education

    Science.gov (United States)

    Hussey, K.

    2016-12-01

    NASA's "Eyes on…" suite of products continues to grow in capability and popularity. The "Eyes on the Earth", "Eyes on the Solar System" and "Eyes on Exoplanets" real-time, 3D interactive visualization products have proven themselves as highly effective demonstration and communication tools for NASA's Earth and Space Science missions. This presentation will give a quick look at the latest updates to the "Eyes" suite plus what is being done to make them tools for STEM Education.

  18. Autologous serum eye drops for dry eye

    Science.gov (United States)

    Pan, Qing; Angelina, Adla; Marrone, Michael; Stark, Walter J; Akpek, Esen K

    2017-01-01

    Background Theoretically, autologous serum eye drops (AS) offer a potential advantage over traditional therapies on the assumption that AS not only serve as a lacrimal substitute to provide lubrication but contain other biochemical components that allow them to mimic natural tears more closely. Application of AS has gained popularity as second-line therapy for patients with dry eye. Published studies on this subject indicate that autologous serum could be an effective treatment for dry eye. Objectives We conducted this review to evaluate the efficacy and safety of AS given alone or in combination with artificial tears as compared with artificial tears alone, saline, placebo, or no treatment for adults with dry eye. Search methods We searched CENTRAL (which contains the Cochrane Eyes and Vision Trials Register) (2016, Issue 5), Ovid MEDLINE, Ovid MEDLINE In-Process and Other Non-Indexed Citations, Ovid MEDLINE Daily, Ovid OLDMEDLINE (January 1946 to July 2016), Embase (January 1980 to July 2016), Latin American and Caribbean Literature on Health Sciences (LILACS) (January 1982 to July 2016), the ISRCTN registry (www.isrctn.com/editAdvancedSearch), ClinicalTrials.gov (www.clinicaltrials.gov) and the World Health Organization (WHO) International Clinical Trials Registry Platform (ICTRP) (www.who.int/ictrp/search/en). We also searched the Science Citation Index Expanded database (December 2016) and reference lists of included studies. We did not use any date or language restrictions in the electronic searches for trials. We last searched the electronic databases on 5 July 2016. Selection criteria We included randomized controlled trials (RCTs) that compared AS versus artificial tears for treatment of adults with dry eye. Data collection and analysis Two review authors independently screened all titles and abstracts and assessed full-text reports of potentially eligible trials. Two review authors extracted data and assessed risk of bias and characteristics of included

  19. MR-eyetracker: a new method for eye movement recording in functional magnetic resonance imaging.

    Science.gov (United States)

    Kimmig, H; Greenlee, M W; Huethe, F; Mergner, T

    1999-06-01

    We present a method for recording saccadic and pursuit eye movements in the magnetic resonance tomograph designed for visual functional magnetic resonance imaging (fMRI) experiments. To reliably classify brain areas as pursuit or saccade related it is important to carefully measure the actual eye movements. For this purpose, infrared light, created outside the scanner by light-emitting diodes (LEDs), is guided via optic fibers into the head coil and onto the eye of the subject. Two additional fiber optical cables pick up the light reflected by the iris. The illuminating and detecting cables are mounted in a plastic eyepiece that is manually lowered to the level of the eye. By means of differential amplification, we obtain a signal that covaries with the horizontal position of the eye. Calibration of eye position within the scanner yields an estimate of eye position with a resolution of 0.2 degrees at a sampling rate of 1000 Hz. Experiments are presented that employ echoplanar imaging with 12 image planes through visual, parietal and frontal cortex while subjects performed saccadic and pursuit eye movements. The distribution of BOLD (blood oxygen level dependent) responses is shown to depend on the type of eye movement performed. Our method yields high temporal and spatial resolution of the horizontal component of eye movements during fMRI scanning. Since the signal is purely optical, there is no interaction between the eye movement signals and the echoplanar images. This reasonably priced eye tracker can be used to control eye position and monitor eye movements during fMRI.

  20. Improved resolution by mounting of tissue sections for laser microdissection.

    Science.gov (United States)

    van Dijk, M C R F; Rombout, P D M; Dijkman, H B P M; Ruiter, D J; Bernsen, M R

    2003-08-01

    Laser microbeam microdissection has greatly facilitated the procurement of specific cell populations from tissue sections. However, the fact that a coverslip is not used means that the morphology of the tissue sections is often poor. To develop a mounting method that greatly improves the morphological quality of tissue sections for laser microbeam microdissection purposes so that the identification of target cells can be facilitated. Fresh frozen tissue and formalin fixed, paraffin wax embedded tissue specimens were used to test the morphological quality of mounted and unmounted tissue. The mounting solution consisted of an adhesive gum and blue ink diluted in water. Interference of the mounting solution with DNA quality was analysed by the polymerase chain reaction using 10-2000 cells isolated by microdissection from mounted and unmounted tissue. The mounting solution greatly improved the morphology of tissue sections for laser microdissection purposes and had no detrimental effects on the isolation and efficiency of amplification of DNA. One disadvantage was that the mounting solution reduced the cutting efficiency of the ultraviolet laser. To minimise this effect, the mounting solution should be diluted as much as possible. Furthermore, the addition of blue ink to the mounting medium restores the cutting efficiency of the laser. The mounting solution is easy to prepare and apply and can be combined with various staining methods without compromising the quality of the DNA extracted.

  1. Eruptive history of Mount Katmai, Alaska

    Science.gov (United States)

    Hildreth, Edward; Fierstein, Judith

    2012-01-01

    Mount Katmai has long been recognized for its caldera collapse during the great pyroclastic eruption of 1912 (which vented 10 km away at Novarupta in the Valley of Ten Thousand Smokes), but little has previously been reported about the geology of the remote ice-clad stratovolcano itself. Over several seasons, we reconnoitered all parts of the edifice and sampled most of the lava flows exposed on its flanks and caldera rim. The precipitous inner walls of the 1912 caldera remain too unstable for systematic sampling; so we provide instead a photographic and interpretive record of the wall sequences exposed. In contrast to the several andesite-dacite stratovolcanoes nearby, products of Mount Katmai range from basalt to rhyolite. Before collapse in 1912, there were two overlapping cones with separate vent complexes and craters; their products are here divided into eight sequences of lava flows, agglutinates, and phreatomagmatic ejecta. Latest Pleistocene and Holocene eruptive units include rhyodacite and rhyolite lava flows along the south rim; a major 22.8-ka rhyolitic plinian fall and ignimbrite deposit; a dacite-andesite zoned scoria fall; a thick sheet of dacite agglutinate that filled a paleocrater and draped the west side of the edifice; unglaciated leveed dacite lava flows on the southeast slope; and the Horseshoe Island dacite dome that extruded on the caldera floor after collapse. Pre-collapse volume of the glaciated Katmai edifice was ∼30 km3, and eruptive volume is estimated to have been 57±13 km3. The latter figure includes ∼40±6 km3 for the edifice, 5±2 km3 for off-edifice dacite pyroclastic deposits, and 12±5 km3 for the 22.8-ka rhyolitic pyroclastic deposits. To these can be added 13.5 km3 of magma that erupted at Novarupta in 1912, all or much of which is inferred to have been withdrawn from beneath Mount Katmai. The oldest part of the edifice exposed is a basaltic cone, which gave a 40Ar/39Ar plateau age of 89 ± 25 ka.

  2. Assembling surface mounted components on ink-jet printed double sided paper circuit board

    International Nuclear Information System (INIS)

    Andersson, Henrik A; Manuilskiy, Anatoliy; Haller, Stefan; Sidén, Johan; Nilsson, Hans-Erik; Hummelgård, Magnus; Olin, Håkan; Hummelgård, Christine

    2014-01-01

    Printed electronics is a rapidly developing field where many components can already be manufactured on flexible substrates by printing or by other high speed manufacturing methods. However, the functionality of even the most inexpensive microcontroller or other integrated circuit is, at the present time and for the foreseeable future, out of reach by means of fully printed components. Therefore, it is of interest to investigate hybrid printed electronics, where regular electrical components are mounted on flexible substrates to achieve high functionality at a low cost. Moreover, the use of paper as a substrate for printed electronics is of growing interest because it is an environmentally friendly and renewable material and is, additionally, the main material used for many packages in which electronics functionalities could be integrated. One of the challenges for such hybrid printed electronics is the mounting of the components and the interconnection between layers on flexible substrates with printed conductive tracks that should provide as low a resistance as possible while still being able to be used in a high speed manufacturing process. In this article, several conductive adhesives are evaluated as well as soldering for mounting surface mounted components on a paper circuit board with ink-jet printed tracks and, in addition, a double sided Arduino compatible circuit board is manufactured and programmed. (paper)

  3. Assembling surface mounted components on ink-jet printed double sided paper circuit board.

    Science.gov (United States)

    Andersson, Henrik A; Manuilskiy, Anatoliy; Haller, Stefan; Hummelgård, Magnus; Sidén, Johan; Hummelgård, Christine; Olin, Håkan; Nilsson, Hans-Erik

    2014-03-07

    Printed electronics is a rapidly developing field where many components can already be manufactured on flexible substrates by printing or by other high speed manufacturing methods. However, the functionality of even the most inexpensive microcontroller or other integrated circuit is, at the present time and for the foreseeable future, out of reach by means of fully printed components. Therefore, it is of interest to investigate hybrid printed electronics, where regular electrical components are mounted on flexible substrates to achieve high functionality at a low cost. Moreover, the use of paper as a substrate for printed electronics is of growing interest because it is an environmentally friendly and renewable material and is, additionally, the main material used for many packages in which electronics functionalities could be integrated. One of the challenges for such hybrid printed electronics is the mounting of the components and the interconnection between layers on flexible substrates with printed conductive tracks that should provide as low a resistance as possible while still being able to be used in a high speed manufacturing process. In this article, several conductive adhesives are evaluated as well as soldering for mounting surface mounted components on a paper circuit board with ink-jet printed tracks and, in addition, a double sided Arduino compatible circuit board is manufactured and programmed.

  4. Assembling surface mounted components on ink-jet printed double sided paper circuit board

    Energy Technology Data Exchange (ETDEWEB)

    Andersson, Henrik A; Manuilskiy, Anatoliy; Haller, Stefan; Sidén, Johan; Nilsson, Hans-Erik [Department of Electronics Design, Mid Sweden University, SE-851 70 Sundsvall (Sweden); Hummelgård, Magnus; Olin, Håkan [Department of Natural Science, Mid Sweden University, SE-851 70 Sundsvall (Sweden); Hummelgård, Christine [Acreo Swedish ICT AB, Håstaholmen 4, SE-824 42 Hudiksvall (Sweden)

    2014-03-07

    Printed electronics is a rapidly developing field where many components can already be manufactured on flexible substrates by printing or by other high speed manufacturing methods. However, the functionality of even the most inexpensive microcontroller or other integrated circuit is, at the present time and for the foreseeable future, out of reach by means of fully printed components. Therefore, it is of interest to investigate hybrid printed electronics, where regular electrical components are mounted on flexible substrates to achieve high functionality at a low cost. Moreover, the use of paper as a substrate for printed electronics is of growing interest because it is an environmentally friendly and renewable material and is, additionally, the main material used for many packages in which electronics functionalities could be integrated. One of the challenges for such hybrid printed electronics is the mounting of the components and the interconnection between layers on flexible substrates with printed conductive tracks that should provide as low a resistance as possible while still being able to be used in a high speed manufacturing process. In this article, several conductive adhesives are evaluated as well as soldering for mounting surface mounted components on a paper circuit board with ink-jet printed tracks and, in addition, a double sided Arduino compatible circuit board is manufactured and programmed. (paper)

  5. Freeze-thaw decellularization of the trabecular meshwork in an ex vivo eye perfusion model

    Directory of Open Access Journals (Sweden)

    Yalong Dang

    2017-08-01

    Full Text Available Objective The trabecular meshwork (TM is the primary substrate of outflow resistance in glaucomatous eyes. Repopulating diseased TM with fresh, functional TM cells might be a viable therapeutic approach. Decellularized TM scaffolds have previously been produced by ablating cells with suicide gene therapy or saponin, which risks incomplete cell removal or dissolution of the extracellular matrix, respectively. We hypothesized that improved trabecular meshwork cell ablation would result from freeze-thaw cycles compared to chemical treatment. Materials and Methods We obtained 24 porcine eyes from a local abattoir, dissected and mounted them in an anterior segment perfusion within two hours of sacrifice. Intraocular pressure (IOP was recorded continuously by a pressure transducer system. After 72 h of IOP stabilization, eight eyes were assigned to freeze-thaw (F ablation (−80 °C × 2, to 0.02% saponin (S treatment, or the control group (C, respectively. The TM was transduced with an eGFP expressing feline immunodeficiency viral (FIV vector and tracked via fluorescent microscopy to confirm ablation. Following treatment, the eyes were perfused with standard tissue culture media for 180 h. TM histology was assessed by hematoxylin and eosin staining. TM viability was evaluated by a calcein AM/propidium iodide (PI assay. The TM extracellular matrix was stained with Picro Sirius Red. We measured IOP and modeled it with a linear mixed effects model using a B-spline function of time with five degrees of freedom. Results F and S experienced a similar IOP reduction of 30% from baseline (P = 0.64. IOP reduction of about 30% occurred in F within 24 h and in S within 48 h. Live visualization of eGFP demonstrated that F conferred a complete ablation of all TM cells and only a partial ablation in S. Histological analysis and Picro Sirius staining confirmed that no TM cells survived in F while the extracellular matrix remained. The viability assay showed

  6. Rack assembly for mounting solar modules

    Science.gov (United States)

    Plaisted, Joshua Reed; West, Brian

    2010-12-28

    A rack assembly is provided for mounting solar modules over an underlying body. The rack assembly may include a plurality of rail structures that are arrangeable over the underlying body to form an overall perimeter for the rack assembly. One or more retention structures may be provided with the plurality of rail structures, where each retention structure is configured to support one or more solar modules at a given height above the underlying body. At least some of the plurality of rail structures are adapted to enable individual rail structures o be sealed over the underlying body so as to constrain air flow underneath the solar modules. Additionally, at least one of (i) one or more of the rail structures, or (ii) the one or more retention structures are adjustable so as to adapt the rack assembly to accommodate solar modules of varying forms or dimensions.

  7. Article mounting and position adjustment stage

    Science.gov (United States)

    Cutburth, Ronald W.; Silva, Leonard L.

    1988-01-01

    An improved adjustment and mounting stage of the type used for the detection of laser beams is disclosed. A ring sensor holder has locating pins on a first side thereof which are positioned within a linear keyway in a surrounding housing for permitting reciprocal movement of the ring along the keyway. A rotatable ring gear is positioned within the housing on the other side of the ring from the linear keyway and includes an oval keyway which drives the ring along the linear keyway upon rotation of the gear. Motor-driven single-stage and dual (x, y) stage adjustment systems are disclosed which are of compact construction and include a large laser transmission hole.

  8. MOUNT HOOD WILDERNESS AND ADJACENT AREAS, OREGON.

    Science.gov (United States)

    Keith, T.E.C.; Causey, J.D.

    1984-01-01

    A mineral survey of the Mount Hood Wilderness, Oregon, was conducted. Geochemical data indicate two areas of substantiated mineral-resource potential containing weak epithermal mineralization: an area of the north side of Zigzag Mountain where vein-type lead-zinc-silver deposits occur and an area of the south side of Zigzag Mountain, where the upper part of a quartz diorite pluton has propylitic alteration associated with mineralization of copper, gold, silver, lead, and zinc in discontinuous veins. Geothermal-resource potential for low- to intermediate-temperature (less than 248 degree F) hot-water systems in the wilderness is probable in these areas. Part of the wilderness is classified as a Known Geothermal Resource Area (KGRA), which is considered to have probable geothermal-resource potential, and two parts of the wilderness have been included in geothermal lease areas.

  9. Photovoltaic array mounting apparatus, systems, and methods

    Science.gov (United States)

    West, John Raymond; Atchley, Brian; Hudson, Tyrus Hawkes; Johansen, Emil

    2014-12-02

    An apparatus for mounting a photovoltaic (PV) module on a surface, including a support with an upper surface, a lower surface, tabs, one or more openings, and a clip comprising an arm and a notch, where the apparatus resists wind forces and seismic forces and creates a grounding electrical bond between the PV module, support, and clip. The invention further includes a method for installing PV modules on a surface that includes arranging supports in rows along an X axis and in columns along a Y axis on a surface such that in each row the distance between two neighboring supports does not exceed the length of the longest side of a PV module and in each column the distance between two neighboring supports does not exceed the length of the shortest side of a PV module.

  10. Insectivore Plants Nepenthes sp. at Mount Merbabu

    Directory of Open Access Journals (Sweden)

    AHMAD DWI SETYAWAN

    2000-07-01

    Full Text Available The aims of the research were to know the existence of the Nepenthes at mount Merbabu, variations of its morphology, associated plants, and ecological conditions. Nepenthes are one of plants that were categorized as conserved plant by Indonesian government as indicated in PPRI No. 7/1999. Many researchers attracted to study this unique plant since it’s distinct feature and the way to get nutrient by trapping insects at its sac. Samples were taken randomly along the path for climbing from Selo, Boyolali to the top of the mountain between April to May 2000. The results show that the plants were found at the altitude of around 1500 to 2000 tsl. There were two forms of the sacs, long and short at the same individual plants. The plants grow coiling on Myristica trees and shrubs of Thunbergia fragrans Roxb., and also could grow at the stoned-soil.

  11. Robotized Surface Mounting of Permanent Magnets

    Directory of Open Access Journals (Sweden)

    Erik Hultman

    2014-10-01

    Full Text Available Using permanent magnets on a rotor can both simplify the design and increase the efficiency of electric machines compared to using electromagnets. A drawback, however, is the lack of existing automated assembly methods for large machines. This paper presents and motivates a method for robotized surface mounting of permanent magnets on electric machine rotors. The translator of the Uppsala University Wave Energy Converter generator is used as an example of a rotor. The robot cell layout, equipment design and assembly process are presented and validated through computer simulations and experiments with prototype equipment. A comparison with manual assembly indicates substantial cost savings and an improved work environment. By using the flexibility of industrial robots and a scalable equipment design, it is possible for this assembly method to be adjusted for other rotor geometries and sizes. Finally, there is a discussion on the work that remains to be done on improving and integrating the robot cell into a production line.

  12. MOUNT PELE, AN ECOCLIMATIC GRADIENT GENERATOR

    Directory of Open Access Journals (Sweden)

    PHILIPPE JOSEPH

    2013-05-01

    Full Text Available Generally, mountains determine the characteristics of particular areas, because of the island phenomenon they cause. However, the geological origins of mountains are multiple and they are located in different climatic regions. Nevertheless, in all aspects they reflect the basic elements of the local biologic unit. The shapes, climates, diverse water resources, biocenoses and the generated soils are the different components that determine, through their dynamic interaction, the “Mountain” ecosystem. Tectonic subduction processes lead to the development of islands such as Martinique, whose basic structure consists of a series of mountains (among them Mount Pele. Like the topographic divisions, the local micro-climates, water courses, different soils (themselves the consequences of the presence of the mountain itself and successive volcanic eruptions determine, over time, the organization of the diverse vegetal entities.

  13. King and Eye

    DEFF Research Database (Denmark)

    Suwannakij, Sing

    King and Eye explores the visual formation of kingship in Siam in its multifarious aspects. This dissertation identifies the leitmotifs in the dynamics between seeing the king and being seen by him, which burst forth in different eras. The visual sense has been a repository for the ontologization...... devices, most significantly the photographic and the cine cameras, but also encompassing other ocular apparatuses. The images produced through the contraptions were brought together under the royal eye at the apex, which in turn claimed its supremacy over space, time, and the vast and diverse population...

  14. Danish Rural Eye Study

    DEFF Research Database (Denmark)

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

    2015-01-01

    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. 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...

  15. Mental Fatigue Monitoring Using a Wearable Transparent Eye Detection System

    Directory of Open Access Journals (Sweden)

    Kota Sampei

    2016-01-01

    Full Text Available We propose mental fatigue measurement using a wearable eye detection system. The system is capable of acquiring movement of the pupil and blinking from the light reflected from the eye. The reflection is detected by dye-sensitized photovoltaic cells. Since these cells are patterned onto the eyeglass and do not require external input power, the system is notable for its lightweight and low power consumption and can be combined with other wearable devices, such as a head mounted display. We performed experiments to correlate information obtained by the eye detection system with the mental fatigue of the user. Since it is quite difficult to evaluate mental fatigue objectively and quantitatively, we assumed that the National Aeronautics and Space Administration Task Load Index (NASA-TLX had a strong correlation with te mental fatigue. While a subject was requested to conduct calculation tasks, the eye detection system collected his/her information that included position, velocity and total movement of the eye, and amount and frequency of blinking. Multiple regression analyses revealed the correlation between NASA-TLX and the information obtained for 3 out of 5 subjects.

  16. Sex-selective QT prolongation during rapid eye movement sleep

    Czech Academy of Sciences Publication Activity Database

    Lanfranchi, P.; Shamsuzzaman, A. S.; Ackerman, M. J.; Kára, T.; Jurák, Pavel; Wolk, R.; Somers, V.

    2002-01-01

    Roč. 106, č. 12 (2002), s. 1488 - 1492 ISSN 0009-7322 R&D Projects: GA ČR GA102/95/0467; GA ČR GA102/02/1339 Institutional research plan: CEZ:AV0Z2065902 Keywords : sleep * sex * nervous system Subject RIV: FA - Cardiovascular Diseases incl. Cardiotharic Surgery Impact factor: 10.255, year: 2002

  17. Causes of blindness in rural Myanmar (Burma: Mount Popa Taung-Kalat Blindness Prevention Project

    Directory of Open Access Journals (Sweden)

    Arie Y Nemet

    2009-07-01

    Full Text Available Arie Y Nemet1, Pinhas Nemet2, Geoff Cohn3, Gina Sutton, Gerald Sutton4, Richard Rawson41Department of Ophthalmology, Sydney Hospital and Sydney Eye Hospital, Sydney, Australia; 2Sackler School of Medicine, Tel-Aviv University, Israel; 3Departments of Ophthalmology, University of New South Wales, Sydney, Australia; 4Department of Ophthalmology, University of Sydney, AustraliaPurpose: This study is a review of the major causes of visual impairment (VI and severe visual impairment/blindness (SVI/BL in Mount Popa Taung-Kalat, a rural region in Myanmar (Burma.Methods: A review of our clinical records of consecutive patients attending clinics was conducted. Participants of all ages (n = 650 of the population of Mount Popa Taung-Kalat and villages in its vicinity underwent ophthalmic interview and a detailed dilated ocular evaluation by trained Australian ophthalmologists and ophthalmic nurses. This evaluation included anterior segment examination with a slit lamp, intraocular pressure recording, and direct or indirect ophthalmoscopy. VI and SVI/BL were defined by the World Health Organization (WHO criteria. Results: Six hundred fifty subjects were screened, with a mean age of 49.0 ± 20.6 years (range, 1–99. One hundred five patients (16.2% were children (ages 1–18. Five hundred thirty-one eyes of the total 1,300 eyes (39.5% had VI/SVI/BL, and 40 eyes of the children (38.1% (average age 15.3 ± 13.3 had VI/SVI/BL. The leading causes of VI/SVI/BL were cataract with 288 cases (54.2%, glaucoma with 84 cases (15.8%, and corneal pathology with 78 cases (14.7%. Of all the VI/SVI/BL cases, 8.4% were preventable, 81.9% were treatable, and total of 90.5% were avoidable.Conclusions: In the current study, cataracts were the major cause of blindness and visual impairment, and most of the ophthalmic pathology causing blindness is avoidable. These results highlight the lack of basic ophthalmologist eye care and optician resources in rural regions in Myanmar

  18. Glaucoma: Eye-to-Eye with Dr. Rachel Bishop

    Science.gov (United States)

    ... of this page please turn JavaScript on. Feature: Glaucoma Eye-to-Eye with Dr. Rachel Bishop Past ... nerves are pale and cupped—signs of advanced glaucoma. Yet the patient wasn't aware of any ...

  19. Scleral Biomechanics in the Aging Monkey Eye

    Science.gov (United States)

    Girard, Michaël J. A.; Suh, J-K. Francis; Bottlang, Michael; Burgoyne, Claude F.; Downs, J. Crawford

    2010-01-01

    Purpose To investigate the age-related differences in the inhomogeneous, anisotropic, nonlinear biomechanical properties of posterior sclera from old (22.9 ± 5.3 years) and young (1.5 ± 0.7 years) rhesus monkeys. Methods The posterior scleral shell of each eye was mounted on a custom-built pressurization apparatus, then intraocular pressure (IOP) was elevated from 5 to 45 mmHg while the 3D displacements of the scleral surface were measured using speckle interferometry. Each scleral shell geometry was digitally reconstructed from data generated by a 3D digitizer (topography) and 20 MHz ultrasounds (thickness). An inverse finite element (FE) method incorporating a fiber-reinforced constitutive model was used to extract a unique set of biomechanical properties for each eye. Displacements, thickness, stress, strain, tangent modulus, structural stiffness, and preferred collagen fiber orientation were mapped for each posterior sclera. Results The model yielded 3-D deformations of posterior sclera that matched well with those observed experimentally. The posterior sclera exhibited inhomogeneous, anisotropic, nonlinear mechanical behavior. The sclera was significantly thinner (p = 0.038), and tangent modulus and structural stiffness were significantly higher in old monkeys (p biomechanics, and potentially contribute to age-related susceptibility to glaucomatous vision loss. PMID:19494203

  20. [Emphasis on standardization and refinement in the diagnosis and treatment of dry eye].

    Science.gov (United States)

    Liu, Z G

    2017-09-11

    Dry eye is the second most common ocular disease. In China, the incidence rate of dry eye has reached 21% to 30%, and dry eye patients have accounted for more than 30% of the total ophthalmology outpatients. Dry eye has become a common health problem that affects the working efficiency and life quality of Chinese people. Over the past decade, due to the rapid development of diagnostic equipments and new treatments for dry eye, dry eye has become one of the areas with greatest concerns in ophthalmology, and many eye institutions have set up their dry eye clinics. Although the diagnosis and treatment of dry eye has been improved in recent years, the awareness of dry eye in Chinese ophthalmologists is still too simple. In the diagnosis, the interrogation and basic examination are not given enough attention, and we are over-relying on equipments. Clinical examination and instrument operation also have not been standardized. This article emphasizes that we should pay attention to the interrogation, basic examination and standardization of clinical examination and equipment operation in diagnosing dry eye. The treatment regimen should be mostly refined and optimized to be individualized and comprehensive based on the causes, types and severity of dry eye. In addition, the physical and adjuvant therapy of dry eye should be given sufficient attention and applied reasonably. (Chin J Ophthalmol, 2017, 53: 641-644) .

  1. About the Eye

    Medline Plus

    Full Text Available ... programs with respect to blinding eye diseases, visual disorders, mechanisms of visual function, preservation of sight, and the special health problems and ... is the center of the macula, where your vision is sharpest. Optic nerve (OP-tic nurv) is the bundle of more than 1 ...

  2. Eye Injuries in Construction

    Science.gov (United States)

    ... cold helps keep down pain and swelling. If pain continues or your vision is blurry, get to a doctor right away. ! If you get hit in the eye with flying metal, wood, or material from a power tool (like a drill or wheel) , OR ! If ...

  3. Robustifying eye interaction

    DEFF Research Database (Denmark)

    Hansen, Dan Witzner; Hansen, John Paulin

    2006-01-01

    This paper presents a gaze typing system based on consumer hardware. Eye tracking based on consumer hardware is subject to several unknown factors. We propose methods using robust statistical principles to accommodate uncertainties in image data as well as in gaze estimates to improve accuracy. We...

  4. About the Eye

    Medline Plus

    Full Text Available ... Accomplishments Budget and Congress About the NEI Director History of the NEI NEI 50th Anniversary NEI Women Scientists Advisory Committee (WSAC) Board of Scientific Counselors National Advisory Eye Council (NAEC) Donating to the NEI Contact Us Visiting the NIH Campus Mission Statement As part ...

  5. About the Eye

    Medline Plus

    Full Text Available ... Institute’s mission is to “conduct and support research, training, health information dissemination, and other programs with respect ... Emily Y. Chew, M.D., Deputy Clinical Director Education Programs National Eye Health Education Program (NEHEP) Diabetic ...

  6. About the Eye

    Medline Plus

    Full Text Available ... of Epidemiology and Clinical Applications eyeGENE Research Directors Office Office of the Scientific Director Sheldon S. Miller, Ph.D., ... David M. Schneeweis, Ph.D., Deputy Scientific Director Office of the Clinical Director Brian P. Brooks, M. ...

  7. What Is Dry Eye?

    Medline Plus

    Full Text Available ... type of tears or tear film . How do tears work? When you blink, a film of tears spreads over the eye. This keeps the eye’s surface smooth and clear. The tear film is important for good vision. The tear ...

  8. LASIK - Laser Eye Surgery

    Science.gov (United States)

    ... Refractive Surgery Procedures What Is Photorefractive Keratectomy (PRK)? LASIK — Laser Eye Surgery Leer en Español: LASIK—Cirugía ocular con láser ... loss of close-up focusing power. How the LASIK procedure works LASIK is performed while the patient ...

  9. What Is Dry Eye?

    Medline Plus

    Full Text Available ... make the right type of tears or tear film . How do tears work? When you blink, a film of tears spreads over the eye. This keeps the eye’s surface smooth and clear. The tear film is important for good vision. The tear film ...

  10. About the Eye

    Medline Plus

    Full Text Available ... Ask a Scientist Video Series Glossary The Visual System Your Eyes’ Natural Defenses Eye Health and Safety ... Employee Emergency Information NEI Intranet (Employees Only) *PDF files require the free Adobe® Reader® software for viewing. ...

  11. Eyes on the Road

    Centers for Disease Control (CDC) Podcasts

    One of the first lessons new drivers learn is to keep their eyes on the road. Unfortunately, cell phones and other electronic devices are causing many drivers to lose their focus, and sometimes their lives. In this podcast, Rebecca Naumann discusses the dangers of distracted driving.

  12. The Learned Eye

    NARCIS (Netherlands)

    Doel, van den Marieke; Eck, van Natasja; Korevaar, Gerbrand; Tummers, Anna; Weststeijn, Thijs

    2005-01-01

    The 'learned eye' or oculus eruditus was a concept used by seventeenth-century writers on painting. It illustrated their view that the ideal artist was not only skilled in painting techniques, but also had knowledge of the history of art and an interest in poetry and literature.In this book,

  13. About the Eye

    Medline Plus

    Full Text Available ... Units Division of Epidemiology and Clinical Applications eyeGENE Research Directors Office Office of the Scientific Director Sheldon S. ... NEI Intranet (Employees Only) *PDF files require the free Adobe® Reader® software for viewing. This website is ...

  14. Laser photocoagulation - eye

    Science.gov (United States)

    ... an eye disorder that slowly destroys sharp, central vision A tear in the retina A blockage of the small veins that carry ... Since parts of the retina are burned, you may develop: Mild loss ... vision If not treated, diabetic retinopathy can cause permanent ...

  15. About the Eye

    Medline Plus

    Full Text Available ... with respect to blinding eye diseases, visual disorders, mechanisms of visual function, preservation of sight, and the ... Contact Us A-Z Site Map NEI on Social Media Information in Spanish (Información en español) Website, ...

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    Full Text Available ... to blinding eye diseases, visual disorders, mechanisms of visual function, preservation of sight, and the special health problems and requirements of ... Pressroom Contacts Dustin Hays - Chief, Science Communication dustin.hays@nih.gov Kathryn DeMott, Media Relations ...

  17. Eye Cosmetic Safety

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    ... you're wearing? In the United States, the use of color additives is strictly regulated. A number of color ... to color additives that are not approved for use in the area of the eye. Avoid color additives that are not approved for use in ...

  18. About the Eye

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    Full Text Available ... programs with respect to blinding eye diseases, visual disorders, mechanisms of visual function, preservation of sight, and the special health ... Pressroom Contacts Dustin Hays - Chief, Science Communication dustin.hays@nih.gov Kathryn DeMott, Media Relations ...

  19. About the Eye

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    Full Text Available ... blinding eye diseases, visual disorders, mechanisms of visual function, preservation of sight, and the special health problems and requirements of the blind.” ... DeMott, Media Relations Kathryn.DeMott@nih.gov NEI Office of Communications ( ...

  20. About the Eye

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    Full Text Available ... the white outer coating of the eye. Vitreous humor (VIT-ree-us HYOO-mer) is the clear ... in Spanish (Información en español) Website, Social Media Policies and Other Important Links NEI Employee Emergency Information ...