WorldWideScience
 
 
1

Three-dimensional system integration for HUD placement on a new tactical airlift platform: design eye point vs. HUD eye box with accommodation and perceptual implications  

Science.gov (United States)

The retrofitting of a cockpit with a Head-Up-Display (HUD) raises potential accommodation and perceptual issues for pilots that must be addressed. For maximum optical efficiency, the goal is to be able to place every pilot's eye into the HUD Eye Motion Box (EMB) given a seat adjustment range. Initially, the Eye Reference Point (ERP) of the EMB should theoretically be located on the aircraft's original cockpit Design Eye Point (DEP), but human postures vary, and HUD systems may not be optimally placed. In reality, there is a distribution of pilot eyes around the DEP (which is dominant eye dependent); therefore, this must be accounted for in order to obtain appropriate visibility of all of the symbology based on photonic characteristics of the HUD. Pilot size and postural variation need to be taken into consideration when positioning the HUD system to ensure proper vision of all HUD symbology in addition to meeting the basic physical accommodation requirements of the cockpit. The innovative process and data collection methods for maximizing accommodation and pilot perception on a new "tactical airlift" platform are discussed as well as the related neurocognitive factors and the effects of information display design on cognitive phenomena.

Harbour, Steven D.; Hudson, Jeffery A.; Zehner, Gregory F.

2012-05-01

2

Eye tracking in user experience design  

CERN Document Server

Eye Tracking for User Experience Design explores the many applications of eye tracking to better understand how users view and interact with technology. Ten leading experts in eye tracking discuss how they have taken advantage of this new technology to understand, design, and evaluate user experience. Real-world stories are included from these experts who have used eye tracking during the design and development of products ranging from information websites to immersive games. They also explore recent advances in the technology which tracks how users interact with mobile devices, large-screen displays and video game consoles. Methods for combining eye tracking with other research techniques for a more holistic understanding of the user experience are discussed. This is an invaluable resource to those who want to learn how eye tracking can be used to better understand and design for their users. * Includes highly relevant examples and information for those who perform user research and design interactive experi...

Romano Bergstorm, Jennifer

2014-01-01

3

Characterizing the point spread function of retinal OCT devices with a model eye-based phantom  

Digital Repository Infrastructure Vision for European Research (DRIVER)

We have designed, fabricated, and tested a nanoparticle-embedded phantom (NEP) incorporated into a model eye in order to characterize the point spread function (PSF) of retinal optical coherence tomography (OCT) devices in three dimensions under realistic imaging conditions. The NEP comprises a sparse distribution of highly backscattering silica-gold nanoshells embedded in a transparent UV-curing epoxy. The commercially-available model eye replicates the key optical structures and focusing po...

Agrawal, Anant; Connors, Megan; Beylin, Alexander; Liang, Chia-pin; Barton, David; Chen, Yu; Drezek, Rebekah A.; Pfefer, T. Joshua

2012-01-01

4

Achromatic Interaction Point Design  

Energy Technology Data Exchange (ETDEWEB)

Designers of high-luminosity energy-frontier muon colliders must provide strong beam focusing in the interaction regions. However, the construction of a strong, aberration-free beam focus is difficult and space consuming, and long straight sections generate an off-site radiation problem due to muon decay neutrinos that interact as they leave the surface of the earth. Without some way to mitigate the neutrino radiation problem, the maximum c.m. energy of a muon collider will be limited to about 3.5 TeV. A new concept for achromatic low beta design is being developed, in which the interaction region telescope and optical correction elements, are installed in the bending arcs. The concept, formulated analytically, combines space economy, a preventative approach to compensation for aberrations, and a reduction of neutrino flux concentration. An analytical theory for the aberration-free, low beta, spatially compact insertion is being developed.

Guimei Wang,, Yaroslav Derbenev, S.Alex Bogacz, P. Chevtsov, Andre Afanaciev, Charles Ankenbrandt, Valentin Ivanov, Rolland P. Johnson

2009-05-01

5

Turning points in reactor design  

International Nuclear Information System (INIS)

This article provides some historical aspects on nuclear reactor design, beginning with PWR development for Naval Propulsion and the first commercial application at Yankee Rowe. Five turning points in reactor design and some safety problems associated with them are reviewed: (1) stability of Dresden-1, (2) ECCS, (3) PRA, (4) TMI-2, and (5) advanced passive LWR designs. While the emphasis is on the thermal-hydraulic aspects, the discussion is also about reactor systems

1995-09-01

6

Turning points in reactor design  

Energy Technology Data Exchange (ETDEWEB)

This article provides some historical aspects on nuclear reactor design, beginning with PWR development for Naval Propulsion and the first commercial application at Yankee Rowe. Five turning points in reactor design and some safety problems associated with them are reviewed: (1) stability of Dresden-1, (2) ECCS, (3) PRA, (4) TMI-2, and (5) advanced passive LWR designs. While the emphasis is on the thermal-hydraulic aspects, the discussion is also about reactor systems.

Beckjord, E.S.

1995-09-01

7

Optimization of Eye End Design of a Single Leaf Spring  

Directory of Open Access Journals (Sweden)

Full Text Available This paper is focused on determination of better eye end design and better material among Titanium and Steel for a single leaf spring. The procedure of this work is to carry out computer aided design and analysis of conventional single leaf spring with actual design considerations and loading conditions. This conventional 65Si7 spring steel leaf spring model and Titanium alloy (Ti 6Al 7Nb with standard eye end, centred eye end and Inverted eye end are considered. The CAD model of the leaf springs is prepared in PRO-E and analysed using ANSYS. Static testing and finite element analysis have been carried out to obtain the characteristics of the spring. The standard eye and centred eye leaf springs are subjected to similar loading conditions. The CAE analysis of the leaf spring is performed for various parameters like Total deflection, von-misses stress and normal stress. The main objective of this work is to determine the better eye end design and select the best material among Steel and Titanium alloy and to reduce the time and cost related to actual experimental testing by providing a CAE solution.

Jayanaidu

2014-05-01

8

Pointing with the eyes: The role of gaze in communicating danger  

Digital Repository Infrastructure Vision for European Research (DRIVER)

Facial expression and direction of gaze are two important sources of social information, and what message each conveys may ultimately depend on how the respective information interacts in the eye of the perceiver. Direct gaze signals an interaction with the observer but averted gaze amounts to "pointing with the eyes", and in combination with a fearful facial expression may signal the presence of environmental danger. We used fMRI to examine how gaze direction influences brain processing of f...

Hadjikhani, Nouchine; Hoge, Rick; Snyder, Josh; Gelder, Beatrice

2008-01-01

9

Innovativeness in design investigated by eye movements and pupillometry  

Directory of Open Access Journals (Sweden)

Full Text Available Innovative designs often break common visual habits by integrating more or less familiar parts into a new concept (Leder & Carbon, 2005. When design innovation is realized in an overly advanced way, the resulting designs tend to be rejected by perceivers at first glance, but seem to be favored when perceivers become more familiar with them (Carbon & Leder, 2005b. In the present study, we investigated the properties of innovative car interior designs by analyzing eye movements and the dilatation of the pupil when evaluating these designs. The analysis of eye movements indicates that innovative designs may be interpreted as more balanced in their conceptual structure. This was shown by an increased number of eye movements directed at the focus areas in car designs. Moreover, pupillometry data demonstrated that innovative designs are cognitively more demanding, thus evoking more interest. Such effects of innovativeness were particularly strong after participants had been exposed to and had elaborately dealt with the material during a phase of familiarization realized by the repeated evaluation technique.

CLAUS-CHRISTIAN CARBON

2006-06-01

10

Complete Phase Diagram of DNA Unzipping: Eye, Y-fork and triple point  

CERN Document Server

We study the unzipping of double stranded DNA (dsDNA) by applying a pulling force at a fraction $s$ $(0 \\le s \\le 1)$ from the anchored end. From exact analytical and numerical results, the complete phase diagram is presented. The phase diagram shows a strong ensemble dependence for various values of $s$. In addition, we show the existence of an ``eye'' phase and a triple point.

Kapri, R; Seno, F; Kapri, Rajeev; Bhattacharjee, Somendra M.; Seno, Flavio

2004-01-01

11

Novel POMGNT1 point mutations and intragenic rearrangements associated with muscle-eye-brain disease  

Science.gov (United States)

Congenital muscular dystrophies due to defects in genes encoding proteins involved in ?-dystroglycan (?-DG) glycosylation are a heterogeneous group of muscle disorders variably associated with central nervous system and eye abnormalities. One of the more severe is muscle-eye-brain disease (MEB). Mutations in genes coding for proven or putative glycosyltransferases (POMT1, POMT2, POMGnT1, fukutin, FKRP, and LARGE), the DPM3 gene encoding a DOL-P-Man synthase subunit, and the DAG1 gene encoding ?-dystroglycan, have been associated with altered ?-DG glycosylation. We report new POMGnT1 mutations and evaluate protein expression in 3 patients and 2 foetuses with variably severe MEB features. We identify two new point mutations (c.643 C > T, c.1863delC), one new intragenic rearrangement (deletion of exons 2–8), and a new intron retention (between exons 21 and 22) resulting from a known point mutation c.1895 + 1 G > T. Our study provides further evidence that rearrangements of the POMGnT1 gene are relatively common. Importantly, if heterozygous, they can be missed on standard genomic DNA sequencing. POMGNT1 protein analysis in 3 patients showed that the severity of the phenotype does not correlate with protein expression. Cerebral MRI is important for identifying MEB and ?-dystroglycanopathy phenotypes in children and foetuses, and hence for directing the genetic analysis.

Saredi, S.; Ardissone, A.; Ruggieri, A.; Mottarelli, E.; Farina, L.; Rinaldi, R.; Silvestri, E.; Gandioli, C.; D'Arrigo, S.; Salerno, F.; Morandi, L.; Grammatico, P.; Pantaleoni, C.; Moroni, I.; Mora, M.

2012-01-01

12

Novel POMGNT1 point mutations and intragenic rearrangements associated with muscle-eye-brain disease.  

Science.gov (United States)

Congenital muscular dystrophies due to defects in genes encoding proteins involved in ?-dystroglycan (?-DG) glycosylation are a heterogeneous group of muscle disorders variably associated with central nervous system and eye abnormalities. One of the more severe is muscle-eye-brain disease (MEB). Mutations in genes coding for proven or putative glycosyltransferases (POMT1, POMT2, POMGnT1, fukutin, FKRP, and LARGE), the DPM3 gene encoding a DOL-P-Man synthase subunit, and the DAG1 gene encoding ?-dystroglycan, have been associated with altered ?-DG glycosylation. We report new POMGnT1 mutations and evaluate protein expression in 3 patients and 2 foetuses with variably severe MEB features. We identify two new point mutations (c.643C>T, c.1863delC), one new intragenic rearrangement (deletion of exons 2-8), and a new intron retention (between exons 21 and 22) resulting from a known point mutation c.1895+1G>T. Our study provides further evidence that rearrangements of the POMGnT1 gene are relatively common. Importantly, if heterozygous, they can be missed on standard genomic DNA sequencing. POMGNT1 protein analysis in 3 patients showed that the severity of the phenotype does not correlate with protein expression. Cerebral MRI is important for identifying MEB and ?-dystroglycanopathy phenotypes in children and foetuses, and hence for directing the genetic analysis. PMID:22554691

Saredi, S; Ardissone, A; Ruggieri, A; Mottarelli, E; Farina, L; Rinaldi, R; Silvestri, E; Gandioli, C; D'Arrigo, S; Salerno, F; Morandi, L; Grammatico, P; Pantaleoni, C; Moroni, I; Mora, M

2012-07-15

13

Inclusive Assessment at Point-of-Design  

Science.gov (United States)

Recognising assessment as a driver for learning and a key part of the student learning experience, this case study considers the impact of opening the assessment process to active student engagement as well as placing inclusivity at the heart of the assessment task at point-of-design. This case study presents an approach to assessment that both…

Keating, Neil; Zybutz, Tanya; Rouse, Karl

2012-01-01

14

Noncontact detection of dry eye using a custom designed IR thermal image system  

Science.gov (United States)

Dry eye syndrome is a common irritating eye disease. Current clinical diagnostic methods are invasive and uncomfortable to patients. A custom designed noncontact infrared (IR) thermal image system was developed to measure the spatial and temporal variation of the ocular surface temperature over a 6-second eye-opening period. We defined two parameters: the temperature difference value and the compactness value to represent the degree of the temperature change and irregularity of the temperature distribution on the tear film. By using these two parameters, in this study, a linear discrimination result for the dry eye and the normal eye groups; the sensitivity is 0.9, the specificity is 0.86 and the receiver operating characteristic (ROC) area is 0.91. The result suggests that the custom designed IR thermal image system may be used as an effective tool for noncontact detection of dry eye.

Su, Tai Yuan; Chen, Kerh Hwa; Liu, Po Hsuan; Wu, Ming Hong; Chang, David O.; Chiang, Huihua

2011-02-01

15

Noncontact detection of dry eye using a custom designed infrared thermal image system  

Science.gov (United States)

Dry eye syndrome is a common irritating eye disease. Current clinical diagnostic methods are invasive and uncomfortable for patients. This study developed a custom designed noncontact infrared (IR) thermal image system to measure the spatial and temporal variation of the ocular surface temperature over a 6-second eye-open period. This research defined two parameters: the temperature difference value and the compactness value to represent the temperature change and the irregularity of the temperature distribution on the tear film. Using these two parameters, this study achieved discrimination results for the dry eye and the normal eye groups; the sensitivity is 0.84, the specificity is 0.83, and the receiver operating characteristic area is 0.87. The results suggest that the custom designed IR thermal image system may be used as an effective tool for noncontact detection of dry eye.

Su, Tai Yuan; Hwa, Chen Kerh; Liu, Po Hsuan; Wu, Ming Hong; Chang, David O.; Su, Po Fang; Chang, Shu Wen; Chiang, Huihua Kenny

2011-04-01

16

Design of Eye Movement Interactive Interface and Example Development  

Digital Repository Infrastructure Vision for European Research (DRIVER)

With the unceasing development of HCI (Human Computer Interaction) technology, natural interactive products are valued by more and more people. The next generation of man-machine interface may use touch, hearing or vision, etc. Among them, the visual sense is the most important channel to get information, but researches are mostly focused on the measurement of eye movement or data processing. In the future, the interaction of eyes with machines will have a very wide prospect. After concluding...

Fang Zhi-Gang; Kong Xiang-Zong; Xu Jie

2013-01-01

17

Design of 3D eye-safe middle range vibrometer  

Science.gov (United States)

Laser Doppler Vibrometer and Range Meter (3D-MRV) is designed for middle range distances [1-100 meters]. 3D-MRV combines more than one laser in one device for a simultaneous real time measuring the distance and movement of the targets. The first laser has a short pulse (t˜30psec) and low energy (E˜200nJ) for distance measurement and the second one is a CW (continuous wave) single frequency laser for the velocity measurement with output power (P˜30mW). Both lasers perform on the eye-safe wavelength 1.5 ?m. 3D-MRV uses the same mono-static optical transmitting and receiving channel for both lasers including an output telescope and a scanning angular system. 3D-MRV has an optical polarization switch to combine linear polarized laser beams from two lasers into one optical channel. The laser beams from both lasers by turns illuminate the target and the scattered laser radiation is collected by the telescope on a photo detector. The electrical signal from photo detector is used for measuring the distance to the target and its movement. For distance measurement the time of flight method is employed. For targets movement the optical heterodyne method is employed. The received CW laser radiation is mixed on a photo detector with the frequency-shifted laser radiation that is taken from CW laser and passed through an acousto-optic cell. The electrical signal from a photo detector on the difference frequency and phase has information about movement of the scattered targets. 3D-MVR may be used for the real time picturing of vibration of the extensive targets like bridges or aircrafts.

Polulyakh, Valeriy; Poutivski, Iouri

2014-05-01

18

Interior Point Methods for Computing Optimal Designs  

CERN Multimedia

In this paper we study interior point (IP) methods for solving optimal design problems. In particular, we propose a primal IP method for solving the problems with general convex optimality criteria and establish its global convergence. In addition, we reformulate the problems with A-, D- and E-criterion into linear or log-determinant semidefinite programs (SDPs) and apply standard primal-dual IP solvers such as SDPT3 [21,25] to solve the resulting SDPs. We also compare the IP methods with the widely used multiplicative algorithm introduced by Silvey et al. [18]. The computational results show that the IP methods generally outperform the multiplicative algorithm both in speed and solution quality. Moreover, our primal IP method theoretically converges for general convex optimal design problems while the multiplicative algorithm is only known to converge under some assumptions.

Lu, Zhaosong

2010-01-01

19

Design of customizable automated low cost eye testing system.  

Science.gov (United States)

Background and Objectives: In many underdeveloped and third world countries, eye care is often neglected due to illiteracy. Particularly people in rural areas suffer with eye problems due to mal nutrition. The government is spending lot of money and efforts in screening the people at periodic intervals. One of the challenges faced by the doctors is screening the school children. Materials and Methods: The standard Snellen letter chart based diagnostic system does not work always. There are instances where the first few students who undergo this diagnostic system, memorize the letter sequence of the Snellen letter chart and convey the same to other fellow students. Hence other students simply read out the Snellen letter sequence from their memory, not by looking at the Snellen letter chart. Thus there is a need of randomizing the sequence of letters being displayed on the Snellen letter chart for every student to be diagnosed for eye testing. Conclusion: In the present paper we are proposing a customizable, software based, cost effective solution which involves a standard personal computer (PC) fitted with a camera, headphone and speaker system. The envisaged system can be administered even by the trained persons. The proposed system is also suitable for remote diagnosis of patients, particularly in the field of telemedicine. PMID:24783089

K, Ganesan; D, Shalini

2014-03-01

20

Novel POMGNT1 point mutations and intragenic rearrangements associated with muscle-eye-brain disease  

Digital Repository Infrastructure Vision for European Research (DRIVER)

Congenital muscular dystrophies due to defects in genes encoding proteins involved in ?-dystroglycan (?-DG) glycosylation are a heterogeneous group of muscle disorders variably associated with central nervous system and eye abnormalities. One of the more severe is muscle-eye-brain disease (MEB). Mutations in genes coding for proven or putative glycosyltransferases (POMT1, POMT2, POMGnT1, fukutin, FKRP, and LARGE), the DPM3 gene encoding a DOL-P-Man synthase subunit, and the DAG1 gene encodi...

Saredi, S.; Ardissone, A.; Ruggieri, A.; Mottarelli, E.; Farina, L.; Rinaldi, R.; Silvestri, E.; Gandioli, C.; D Arrigo, S.; Salerno, F.; Morandi, L.; Grammatico, P.; Pantaleoni, C.; Moroni, I.; Mora, M.

2012-01-01

 
 
 
 
21

Design of integrated eye tracker-display device for head mounted systems  

Science.gov (United States)

We propose an Eye Tracker/Display system, based on a novel, dual function device termed ETD, which allows sharing the optical paths of the Eye tracker and the display and on-chip processing. The proposed ETD design is based on a CMOS chip combining a Liquid-Crystal-on-Silicon (LCoS) micro-display technology with near infrared (NIR) Active Pixel Sensor imager. The ET operation allows capturing the Near IR (NIR) light, back-reflected from the eye's retina. The retinal image is then used for the detection of the current direction of eye's gaze. The design of the eye tracking imager is based on the "deep p-well" pixel technology, providing low crosstalk while shielding the active pixel circuitry, which serves the imaging and the display drivers, from the photo charges generated in the substrate. The use of the ETD in the HMD Design enables a very compact design suitable for Smart Goggle applications. A preliminary optical, electronic and digital design of the goggle and its associated ETD chip and digital control, are presented.

David, Y.; Apter, B.; Thirer, N.; Baal-Zedaka, I.; Efron, U.

2009-08-01

22

High Pulse Repetition Rate, Eye Safe, Visible Wavelength Lidar Systems: Design, Results and Potential  

Science.gov (United States)

In 1993 the first of the eye safe visible wavelength lidar systems known now as Micro Pulse Lidar (MPL) became operational. Since that time there have been several dozen of these systems produced and applied for full time profiling of atmospheric cloud and aerosol structure. There is currently an observational network of MPL sites to support global climate research. In the course of application of these instruments there have been significant improvements in understanding, design and performance of the systems. There are addition potential and applications beyond current practice for the high repetition rate, eye safe designs. The MPL network and the current capability, design and future potential of MPL systems are described.

Spinhirne, James; Berkoff, Timothy; Welton, Elsworth; Campbell, James; OCStarr, David (Technical Monitor)

2002-01-01

23

Dynamics and mission design near libration points  

CERN Multimedia

It is well known that the restricted three-body problem has triangular equilibrium points. These points are linearly stable for values of the mass parameter, µ , below Routh's critical value, µ 1 . It is also known that in the spatial case they are nonlinearly stable, not for all the initial conditions in a neighborhood of the equilibrium points L 4 , L 5 but for a set of relatively large measures. This follows from the celebrated Kolmogorov-Arnold-Moser theorem. In fact there are neighborhoods of computable size for which one obtains "practical stability" in the sense that the massless partic

Gómez, G; Llibre, J; Martínez, R

2001-01-01

24

Dynamics and mission design near libration points  

CERN Document Server

The aim of this book is to explain, analyze and compute the kinds of motions that appear in an extended vicinity of the geometrically defined equilateral points of the Earth-Moon system, as a source of possible nominal orbits for future space missions. The methodology developed here is not specific to astrodynamics problems. The techniques are developed in such a way that they can be used to study problems that can be modeled by dynamical systems. Contents: Global Stability Zones Around the Triangular Libration Points; The Normal Form Around L 5 in the Three-dimensional RTBP; Normal Form of th

Gómez, G; Jorba, A; Masdemont, J

2001-01-01

25

Deep Water Single Point Mooring Design.  

Science.gov (United States)

This report presents the results of a feasibility study of single point mooring (SPM) systems for the Mobile Offshore Base, a very large semi-submerged platform, in up to 10,000 ft (3000 m) water depth. The MOB will use the mooring in mild environments. T...

H. A. McKenna J. F. Flory

1997-01-01

26

Aalto University Design Factory in the eyes of its community  

Digital Repository Infrastructure Vision for European Research (DRIVER)

This report concerns Aalto University Design Factory (ADF), one of the spearhead projects and first physical manifestations of Aalto University. ADF aims to be a platform for integrative interdisciplinary education, research and industrial collaboration, as well as a catalyst for a culture of experimental and problem-based education to promote better learning outcomes. Since opening its doors in November 2008, ADF has strived to achieve these by providing a non-hierarchical, constantly develo...

Bjo?rklund, Tua; Clavert, Maria; Kirjavainen, Senni; Laakso, Miko; Luukkonen, Satu

2011-01-01

27

Factor Xa: simulation studies with an eye to inhibitor design.  

Science.gov (United States)

Factor Xa is a serine protease which activates thrombin and plays a key regulatory role in the blood-coagulation cascade. Factor Xa is at the crossroads of the extrinsic and intrinsic pathways of coagulation and, hence, has become an important target for the design of anti-thrombotics (inhibitors). It is not known to be involved in other processes than hemostasis and its binding site is different to that of other serine proteases, thus facilitating selective inhibition. The design of high-affinity selective inhibitors of factor Xa requires knowledge of the structural and dynamical characteristics of its active site. The three-dimensional structure of factor Xa was resolved by X-ray crystallography and refined at 2.2 A resolution by Padmanabhan and collaborators. In this article we present results from molecular dynamics simulations of the catalytic domain of factor Xa in aqueous solution. The simulations were performed to characterise the mobility and flexibility of the residues delimiting the unoccupied binding site of the enzyme, and to determine hydrogen bonding propensities (with protein and with solvent atoms) of those residues in the active site that could interact with a substrate or a potential inhibitor. The simulation data is aimed at facilitating the design of high-affinity selective inhibitors of factor Xa. PMID:10921769

Daura, X; Haaksma, E; van Gunsteren, W F

2000-08-01

28

Laser designation for improving payload pointing accuracy  

Science.gov (United States)

The US armed forces will plan and conduct operational maneuvers from the sea and sustained operations ashore. These deployments will require accurate target acquisition and designation beyond line-of-sight, under limited visibility, and during day or night engagements. A laser target designator/rangefinder boresighted to a FLIR or day camera can perform accurate ranging and target acquisition from an unmanned aerial vehicle (UAV) platform. To meet the mission needs of the US Marine Expeditionary Warfighters, the US Army's and Navy's need for precision targeting for Hellfire, Copper Head, and other laser guided ordinance, the UAV Joint Project Office is evaluating NDI laser designator payloads for UAV application. During the upcoming laser designator evaluation on the Hunter UAV, critical laser parameters will be measured: beam dispersion, energy level, pulse width, stability, amplitude, jitter and payload autotrack performance. The purpose of this and future demonstrations/evaluations is to characterize the laser designators/rangefinders performance on various targets at various ranges. These tests will determine the maximum effective range versus target types and UAV stability parameters. Test data will provide valuable information for future laser designator/rangefinder demonstrations on the Tactical UAV, Predator, and Pioneer.

Dixon, Walter

1996-05-01

29

Design and DSP Implementation of Fixed-Point Systems  

Digital Repository Infrastructure Vision for European Research (DRIVER)

This article is an introduction to the FRIDGE design environment which supports the design and DSP implementation of fixed-point digital signal processing systems. We present the tool-supported transformation of signal processing algorithms coded in floating-point ANSI C to a fixed-point representation in SystemC. We introduce the novel approach to control and data flow analysis, which is necessary for the transformation. The design environment enables fast bit-true simulation by mapping the ...

Heinrich Meyr; Olaf Lüthje; Holger Keding; Martin Coors

2002-01-01

30

NIF Ignition Target 3D Point Design  

Energy Technology Data Exchange (ETDEWEB)

We have developed an input file for running 3D NIF hohlraums that is optimized such that it can be run in 1-2 days on parallel computers. We have incorporated increasing levels of automation into the 3D input file: (1) Configuration controlled input files; (2) Common file for 2D and 3D, different types of capsules (symcap, etc.); and (3) Can obtain target dimensions, laser pulse, and diagnostics settings automatically from NIF Campaign Management Tool. Using 3D Hydra calculations to investigate different problems: (1) Intrinsic 3D asymmetry; (2) Tolerance to nonideal 3D effects (e.g. laser power balance, pointing errors); and (3) Synthetic diagnostics.

Jones, O; Marinak, M; Milovich, J; Callahan, D

2008-11-05

31

Some points of advanced alarm system design  

International Nuclear Information System (INIS)

A description of some of the more relevant questions relating to advanced alarm systems for nuclear power plant installations. The development of such alarm systems embodies three main tasks: development of formal alarm handling methods, design of alarm patterns, development of alarm analysis systems. The major aspects of these tests are dealt with and the close relation between the alarm analysis and the plant disturbance analysis procedure is emphasized. (author)

1977-01-01

32

ARIES-ST design point selection  

International Nuclear Information System (INIS)

The spherical tokamak (ST) regime of low-aspect-ratio (LAR) tokamak operation has provided an opportunity to consider a 1000-MWe(net) D-T power plant conceptual design, designated ARIES-ST. Physics attributes include high beta (?50%) together with high bootstrap current contribution (?95%). Neutral-beam current drive (?28 MW) supports steady-state operation. The plasma aspect ratio was selected to be A?1.6 leading to the choice of major plasma toroidal radius, RT=3.2 m and plasma half-width, a=2.0 m. The usual engineering considerations of providing an efficient thermal power cycle (gross efficiency ?45%), while handling first-wall (?1 MW/m2) and divertor-plate (?5 MW/m2) surface heat fluxes, leads to 14-MeV neutron wall loads near 4.1 MW/m2 (average) and 5.6 MW/m2 (peak at outboard mid-plane) in a dual (PbLi and He) coolant system. The water-cooled toroidal-field-coil (TFC) centerpost is protected by a 20-cm (inboard) shield that does not breed tritium. Joule dissipation in the TFC system provides the major contribution to the plant recirculating power; specifically, Cu centerpost (222 MW), Al outboard shell (47 MW), Cu leads (27 MW), and power supplies (33 MW). The overall plant recirculating power fraction is an uncomfortable 34%. For a plant capacity factor ?76%, consistent with earlier ARIES studies, the COE is projected to be ?84 mill/kWe h (1992 constant $), using similar unit-cost assumptions and some passive-safety cost credits. Inclusion of additional credits for advanced, low-unit-cost manufacturing based on plasma spray and related techniques (as applied to the TFC centerpost and outboard TFC shell only) lowers this COE estimate to ?79 mill/kWe h

2003-02-01

33

The Age-Related Eye Disease Study (AREDS): Design Implications AREDS Report No. 1  

Digital Repository Infrastructure Vision for European Research (DRIVER)

The Age-Related Eye Disease Study (AREDS) was initially conceived as a long-term multicenter, prospective study of the clinical course of age-related macular degeneration (AMD) and age-related cataract. Data on progression rates and risk factors from the study will increase understanding of the clinical course of both conditions, generate hypotheses about etiology, and aid in the design of clinical trials of potential interventions. In addition to collecting natural history data, AREDS includ...

1999-01-01

34

Customized schematic eye model for refraction correction design based on ocular wavefront and corneal topography measurements  

Science.gov (United States)

The subject of this paper relates to the ocular optical design and vision analysis of refractive correction of the eye. After the purpose statement and the assumption list, the concept of the schematic eye matching a particular (measured) wavefront is introduced. This concept is based on the fact that the ocular wavefront, together with the corneal topography, can be seen as the mathematical global representation of the eye working in monochromatic light and having a foveal vision. The discussed design technique, including an iterative optimization method, could be applied in any ocular correction that utilizes cornea topography and/or ocular wavefront, e.g. contact lens or intra-corneal implant. However, the application this paper refers to is the ocular refractive correction by a procedure using the LADARVISION. It consists of surgical removal and subsequent replacement of a corneal flap on a stromal surface whose shape has been changed by laser ablation of the tissue. Subsequent sections of this paper are dedicated to establishing the limits of possible refractive correction, the influences of the flap and corneal topography into the refractive correction calculation. Finally a realistic evaluation of the results and a list of possible developments of this new optical design method are discussed.

Curatu, Eugene O.; Pettit, George H.; Campin, John A.

2002-06-01

35

An updated point design for heavy ion fusion  

International Nuclear Information System (INIS)

An updated, self-consistent point design for a heavy ion fusion (HIF) power plant based on an induction linac driver, indirect-drive targets, and a thick liquid wall chamber has been completed. Conservative parameters were selected to allow each design area to meet its functional requirements in a robust manner, and thus this design is referred to as the Robust Point Design (RPD-2002). This paper provides a top-level summary of the major characteristics and design parameters for the target, driver, final focus magnet layout and shielding, chamber, beam propagation to the target, and overall power plant

2002-11-17

36

Frequency of secondary cataract development in pseudophakic eyes with posterior chamber IOL of current designs in case of axial myopia  

Directory of Open Access Journals (Sweden)

Full Text Available ABSTRACT Purpose. To evaluate a frequency of secondary cataract development in different periods of postoperative follow-up after cataract phacoemulsification depending on the degree of axial myopia and the implanted IOL design. Material and methods. A retrospective analysis of secondary cataract formation in the long-term follow-up after cataract phacoemulsification with foldable intraocular lens implantation was performed in 16575 eyes out of 8722 patients with emmetropia and axial myopia. The average age of patients was 74±7 years, and the follow-up period was 5 years. The eyes with associated pathology such as glaucoma, diabetic retinopathy etc, were excluded from the study. Depending on the design of implanted IOL all eyes were divided into 3 groups. The first group included 5527 eyes with the implanted B-lens IOL (Hanita, Israel. The second group included 5629 eyes with the implanted Idea IOL (XCELENS, Switzerland. The third group consisted of 5419 eyes with the implanted Acrysof natural, SA60AT IOL (Alcon, USA. In every case the degree of myopia was evaluated using axial length of an eye that was measured instrumentally. The incidence of secondary cataract formation was evaluated on quantity of YAG-laser posterior capsule dissection within the 5-year follow-up after phacoemulsification with IOL implantation. Conclusion. According to our results the incidence of PCO is directly dependent on the axial length of the eye, strongly increasing in eyes with high axial myopia. The design and material of implanted IOL played an important role in PCO formation too. The eyes with the Acrysof natural, SA60AT IOL (Alcon, USA had the lowest incidence of PCO in the long-term follow-up.

G.V. Sorokoletov

2013-02-01

37

Accuracy Constraint Determination in Fixed-Point System Design  

Directory of Open Access Journals (Sweden)

Full Text Available Most of digital signal processing applications are specified and designed with floatingpoint arithmetic but are finally implemented using fixed-point architectures. Thus, the design flow requires a floating-point to fixed-point conversion stage which optimizes the implementation cost under execution time and accuracy constraints. This accuracy constraint is linked to the application performances and the determination of this constraint is one of the key issues of the conversion process. In this paper, a method is proposed to determine the accuracy constraint from the application performance. The fixed-point system is modeled with an infinite precision version of the system and a single noise source located at the system output. Then, an iterative approach for optimizing the fixed-point specification under the application performance constraint is defined and detailed. Finally the efficiency of our approach is demonstrated by experiments on an MP3 encoder.

Serizel R

2008-01-01

38

Accuracy Constraint Determination in Fixed-Point System Design  

Directory of Open Access Journals (Sweden)

Full Text Available Most of digital signal processing applications are specified and designed with floatingpoint arithmetic but are finally implemented using fixed-point architectures. Thus, the design flow requires a floating-point to fixed-point conversion stage which optimizes the implementation cost under execution time and accuracy constraints. This accuracy constraint is linked to the application performances and the determination of this constraint is one of the key issues of the conversion process. In this paper, a method is proposed to determine the accuracy constraint from the application performance. The fixed-point system is modeled with an infinite precision version of the system and a single noise source located at the system output. Then, an iterative approach for optimizing the fixed-point specification under the application performance constraint is defined and detailed. Finally the efficiency of our approach is demonstrated by experiments on an MP3 encoder.

O. Sentieys

2008-10-01

39

Design of a reversible single precision floating point subtractor.  

Science.gov (United States)

In recent years, Reversible logic has emerged as a major area of research due to its ability to reduce the power dissipation which is the main requirement in the low power digital circuit design. It has wide applications like low power CMOS design, Nano-technology, Digital signal processing, Communication, DNA computing and Optical computing. Floating-point operations are needed very frequently in nearly all computing disciplines, and studies have shown floating-point addition/subtraction to be the most used floating-point operation. However, few designs exist on efficient reversible BCD subtractors but no work on reversible floating point subtractor. In this paper, it is proposed to present an efficient reversible single precision floating-point subtractor. The proposed design requires reversible designs of an 8-bit and a 24-bit comparator unit, an 8-bit and a 24-bit subtractor, and a normalization unit. For normalization, a 24-bit Reversible Leading Zero Detector and a 24-bit reversible shift register is implemented to shift the mantissas. To realize a reversible 1-bit comparator, in this paper, two new 3x3 reversible gates are proposed The proposed reversible 1-bit comparator is better and optimized in terms of the number of reversible gates used, the number of transistor count and the number of garbage outputs. The proposed work is analysed in terms of number of reversible gates, garbage outputs, constant inputs and quantum costs. Using these modules, an efficient design of a reversible single precision floating point subtractor is proposed. Proposed circuits have been simulated using Modelsim and synthesized using Xilinx Virtex5vlx30tff665-3. The total on-chip power consumed by the proposed 32-bit reversible floating point subtractor is 0.410 W. PMID:24455466

Anantha Lakshmi, Av; Sudha, Gf

2014-01-01

40

Design and Implementation of Complex Floating Point Processor Using FPGA  

Directory of Open Access Journals (Sweden)

Full Text Available This paper presents complete processor hardware with three arithmetic units. The first arithmetic unit canperform 32-bit integer arithmetic operations. The second unit can perform arithmetic operations such asaddition, subtraction, multiplication, division, and square root on 32-bit floating point numbers. The thirdunit can perform arithmetic operations such as addition, subtraction, multiplication on complex numbers.The specific advancement in this processor is the new architecture introduced for complex arithmetic unit.In general complex floating point arithmetic hardware consists of floating to fixed and fixed to floatingconversions. But using such hardware will lead to compromise between accuracy and number of bits usedto represent the fixed point equivalent of floating point numbers. The proposed architecture avoids thatcompromise and it is implemented with less number of look-up tables to save around 5500 logic gates. Thecomplex numbers are represented using a subset of IEEE754 standard floating point format, 16-bits forreal part and 16-bits for imaginary part. The floating point arithmetic unit works on 32-bit IEEE754 singleprecision numbers. The instruction set is specially designed to support integer, floating point and complexfloating point arithmetic operations. The on-chip RAM is 8kBytes and is extendable up to 64kBytes. As theprocessor is designed to implement on FPGA, the embedded block RAMs are utilized as RAM.

Murali Krishna Pavuluri

2013-10-01

 
 
 
 
41

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

Directory of Open Access Journals (Sweden)

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

Dandona Rakhi

1997-01-01

42

Design of a population-based study of visual impairment in India: The Andhra Pradesh Eye Disease Study.  

Science.gov (United States)

Reliable population-based epidemiologic data regarding vision and ocular morbidity, as well as those about the perceptions of people regarding visual impairment and eye care, are lacking for the most part in the developing world including India. These data are the basis on which effective eye care services can be developed. To meet this need we designed the Andhra Pradesh Eye Disease Study, a population-based epidemiology study of 10,000 people in the Indian state of Andhra Pradesh. The design of this study is described in this paper. Various options for the sample size, study areas, sampling procedure, and recruitment of subjects were considered. A sample size of 10,000 people, 5,000 each in the 30 years age groups, was determined to obtain reasonable confidence in estimating the prevalence of diseases and odds ratios for risk factors of interest. A multistage sampling strategy was chosen for the study which was assumed to give a design effect of 1.5 for the estimates. One urban area, Hyderabad, and three rural areas, West Godavari, Adilabad and Mahbubnagar districts, were selected in Andhra Pradesh. Interview instruments were developed to obtain detailed information about demographic data, diet, ocular and systemic history, risk factors for eye diseases, visual function, quality of life, barriers to eye care, and knowledge about eye diseases. A detailed examination procedure was devised to obtain a broad range of normative and abnormal data related to eyes and vision. A protocol was developed for doing automated visual fields, slitlamp and fundus photography. Computer databases were made in FoxPro for data entry and subsequent analysis with SPSS. Pilot studies were done to test the instruments, procedures, and logistics of the study in urban and rural areas. Information from the Andhra Pradesh Eye Disease Study is expected to help in planning and implementation of effective long-term preventive, curative, and rehabilitative eye care services in Andhra Pradesh. PMID:9567024

Dandona, R; Dandona, L; Naduvilath, T J; Nanda, A; McCarty, C A

1997-12-01

43

Professional SharePoint 2010 Branding and User Interface Design  

CERN Document Server

A must have guide for creating engaging and usable SharePoint 2010 brandingWith SharePoint 2010, Microsoft has provided a more robust environment for creating collaboration and content management sites that rival any of the popular websites on the internet. Creating a branded SharePoint site involves understanding both traditional web design techniques as well as topics that are typically reserved for developers. This book bridges that gap by not only providing expert guidance for creating beautiful public facing and internal intranet sites but it also addresses the needs of those readers that

Drisgill, Randy; Sanford, Jacob J; Stubbs, Paul; Riemann, Larry

2010-01-01

44

End points and clinical trial design in pulmonary arterial hypertension.  

Science.gov (United States)

New and emerging therapies might provide benefit in patients with pulmonary arterial hypertension. Their efficacy and safety will be compared with existing combination therapies in randomized clinical trials. Appropriate end points for these trials need to be identified: these will include exercise testing, the composite end point of time to clinical worsening, and hemodynamic markers, including advanced imaging modalities and biomarkers. Quality-of-life questionnaires are useful and important secondary end points; pulmonary arterial hypertension-specific questionnaires are currently being developed. Advantages and disadvantages of various trial designs, including placebo-controlled monotherapy or add-on trials, noninferiority studies, and withdrawal trials are also discussed. PMID:19555863

McLaughlin, Vallerie V; Badesch, David B; Delcroix, Marion; Fleming, Thomas R; Gaine, Sean P; Galiè, Nazzareno; Gibbs, J Simon R; Kim, Nick H; Oudiz, Ronald J; Peacock, Andrew; Provencher, Steeve; Sitbon, Olivier; Tapson, Victor F; Seeger, Werner

2009-06-30

45

Optimum design point for a closed-cycle OTEC system  

Energy Technology Data Exchange (ETDEWEB)

Performance analysis is performed for optimum design point of a closed-cycle Ocean Thermal Energy Conversion (OTEC) system. Calculations are made for an OTEC model plant with a gross power of 100 MW, which was designed by the optimization method proposed by Uehara and Ikegami for the design conditions of 21 C--29 C warm sea water temperature and 4 C cold sea water temperature. Ammonia is used as working fluid. Plate type evaporator and condenser are used as heat exchangers. The length of the cold sea water pipe is 1,000 m. This model plant is a floating-type OTEC plant. The objective function of optimum design point is defined as the total heat transfer area of heat exchangers per the annual net power.

Ikegami, Yasuyuki; Uehara, Haruo [Saga Univ. (Japan)

1994-12-31

46

Eye movement  

International Nuclear Information System (INIS)

This is a special lecture at the 96th Annual Congress of the Japanese Ophthalmological Society in 1992, presenting studies on eye movement using magnetic resonance imaging (MRI). Using cine mode MRI technology, two methods for producing a series of photographs have been invented: (1) the moving eye method or dynamic method in which the subjects were asked to perform 256 or 512 vertical and horizontal eye movements in synchronization with a sound trigger; and (2) the fixed eye method or static method in which the subjects were asked to gaze at individual points in a 5 to 7 point sequence as indicated by the investigator. MRI data was generated and the resulting series of photographs were observed in cine mode on a televisin monitor. Displaying the MRI-generated photographs in cine mode enables direct observation of eye movement, optic nerve and extraocular muscles within the orbit. Although the moving eye method is more accurate in its portrayal of the actual eye movement, at least 256 eye movements are required for about 5 minutes, causing physical and mental load for the subjects. The fixed eye method was thus used to examine ophthalmoplegia, including abducens palsy, oculomotor palsy, fracture of the orbital wall, foreign bodies in the orbit, Duane's syndrome, endocrine myopathy, esotropia and exotropia. This allowed the investigation of anatomical changes, such as atrophy or hypertrophy, and the functional state caused by contraction and relaxation of the extraocular muscles. Transposition of the extraocular muscles for paralytic squint was reexamined and a new surgical procedure was developed for abducens palsy. The measurement of the length, thickness and weight of the extraocular muscles from the MRI-generated photographs allowed more accurate analysis. Three dimensional reconstructive method of MRI provided a valuable tool for evaluating the orbit. (N.K.) 67 refs

1992-12-01

47

Design of Point Focusing Total-Reflection Zone Plate  

International Nuclear Information System (INIS)

We designed point focusing total-reflection zone plates (TRZPs): a double linear type TRZP in Kirkpatrick-Baez arrangement, a conical TRZP, and an open conical TRZP. In this paper, we show detail characteristics of the open conical TRZP, which is the most promising candidate for practical use, and evaluate the effect of fabrication error and misalignment on focused beam profiles by calculation

2013-10-25

48

Calibration of a Shack-Hartmann Sensor (SHS) with a point diffraction interferometer (PDI) to measure the wavefront aberrations of the human eye  

Science.gov (United States)

To measure the wavefront aberrations of human eyes, a Shack-Hartmann Sensor (SHS) was developed at UNAM-CCADET. Usually, for calibrating the SHS a well corrected collimated beam is used, so the evaluation of the aberrations depends on this calibration. We propose to use a Point Diffraction Interferometer (PDI) in parallel with the SHS, in order to be able to check for aberrations in the calibration beam at any time. This allows reducing the delay between the calibration and measurement of the aberrations of the eye made with the SHS. In addition, both measurements are made without moving components, so the evaluation made through the SHS can be compensated with the reference beam measurement made by the PDI. The results of the quantitative evaluation of the wavefront aberrations of a human eye are presented in this paper.

García-Flores, P.; Díaz-Uribe, R.

2011-08-01

49

Eye Safe, Visible Wavelength Lidar Systems: Design and Operational Advances, Results and Potential  

Science.gov (United States)

In the early nineties the first of the eye safe visible wavelength lidar systems known now as Micro Pulse Lidar (MPL) became operational. The important advance of the design was a system that, unlike most existing lidar, operated at eye safe energy densities and could thus operate unattended for full time monitoring. Since that time there have been many dozens of these systems produced and applied for full time profiling of atmospheric cloud and aerosol structure. There is currently an observational network of MPL sites to support global climate research. In thc course of application of these instruments there have been significant improvements in the, design and performance of the systems. In the last half decade particularly there has been significant application and technical development of MPL systems. In this paper we review progress. The current MPL systems in use are all single wavelength systems designed for cloud and aerosol applications. For the cloud and aerosol applications, both lidar depolarization and multi wavelength measurements have significant applications. These can be accomplished with the MPL, approach. The main current challenge for the lidar network activity are in the area of the reliability, repeatability and efficiency of data processing. The network makes use of internet data downloads and automated processing. The heights of all cloud and aerosol layers are needed. The recent emphasis has been in operationally deriving aerosol extinction cross section. Future emphasis will include adding cirrus optical parameters. For operational effectiveness, improvements to simplify routine data signal calibration are being researched. Overall the MPL systems have proven very effective. A large data base of results from globally distributed sites can be easily accessed through the internet. Applications have included atmospheric model development. Validation of current global satellite observations of aerosol and clouds, including now orbital lidar observations, was a primary goal for NASA. Although sampling issues require careful consideration, results have proven useful.

Spinhirne, James; Welton, Ellsworth J.; Berkoff, Timothy; Campbell, James

2007-01-01

50

An iodine-125 applicator designed for irradiating blood vessels growing into the cornea of the eye  

International Nuclear Information System (INIS)

The invasion of the traumatized cornea by blood vessels is a well known complication is often associated with graft rejection. Graft acceptance may be improved by the induction of endarteritis with ? radiation but the corneal stroma may be so changed by the necessary dose of radiation (commonly 4500-5000 cGy in three or four fractions) as to significantly increase the risk of sloughing (Macfaul and Bedford, 1970). To overcome this problem, the authors have designed and made an 125I eye applicator to produce an extremely narrow radiation field for treating the vascularization at the base of the cornea only. The anterior part of the cornea receives a very small dose of about 11% of that given to the base and is sufficiently large to receive a 6mm corneal transplant. (author)

1989-01-01

51

Computing Optimal Experimental Designs via Interior Point Method  

Digital Repository Infrastructure Vision for European Research (DRIVER)

In this paper, we study optimal experimental design problems with a broad class of smooth convex optimality criteria, including the classical A-, D- and p th mean criterion. In particular, we propose an interior point (IP) method for them and establish its global convergence. Furthermore, by exploiting the structure of the Hessian matrix of the aforementioned optimality criteria, we derive an explicit formula for computing its rank. Using this result, we then show that the N...

Lu, Zhaosong; Pong, Ting Kei

2010-01-01

52

Oil-points - Designers means to evaluate sustainability of concepts  

DEFF Research Database (Denmark)

Designers have an essential influence on product design and are therefore one target group for environmental evaluation methods. This implies, that such evaluation methods have to meet designers requirements. Evaluation of sustainability of products is often done using formal Life Cycle Assessment (LCA) methods. The different LCA based methodologies consider different environmental exchanges and are often rather complex.In this context, the authors raise the question, whether a simplified LCA method which is only based on energy considerations can be used as a tool for quick overviews. This is investigated by means of three case studies where environmental impact is estimated using the EDIP method, the Eco-indicator 95 method, and the Oil Point method proposed by the authors. It is found that the results obtained using Oil Points are in acceptable conformity with the results obtained with more complex methods. This, however, is only valid as long as chemical substances can be neglected in the considered life cycle systems. Comments from workshops with designers, where the cases were presented, are included in the paper.

Bey, Niki; Lenau, Torben Anker

1998-01-01

53

The Evonik-Mainz-Eye-Care-Study (EMECS): Design and Execution of the Screening Investigation  

Science.gov (United States)

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

Barleon, Lorenz; Wahl, Jochen; Morfeld, Peter; Deters, Claudia; Lichtme?, Andrea; Haas-Brahler, Sibylle; Muller, Uta; Breitstadt, Rolf; Pfeiffer, Norbert

2014-01-01

54

Fixed-point multiplier evaluation and design with FPGA  

Science.gov (United States)

The hardware implementation of fixed-point multiplication has become a standard feature in almost all processors and computing systems. Though many researchers have studied various multiplication techniques for ASIC technology, the same techniques may not yield the same performance for FPGA- based multipliers. In this paper, we investigate the costs and speed performances associated with various multiplication techniques implemented on a single XC4010PQ160-5 device. The investigation reveals the significant performance influencing factors for effective design of FPGA-based multipliers. Based on the understanding of the revealed performance influencing factors, we propose a parallel multiplication technique appropriate for FPGA implementations. The implementation results demonstrate that the proposed technique is valid and effective. This paper offers useful references for FPGA-based computing unit designs, and provides an important groundwork for effective design and development of FPGA-based computing systems.

Yu, William W.; Xing, Shanzhen

1999-08-01

55

Dynamic changes in corneal topography and its influence on the point-spread function of the eye  

Science.gov (United States)

The dynamic changes of the anterior surface of the eye are investigated. A Twyman-Green interferometer is used to record topographic images at 40 ms intervals. A method of analysis of the dynamic changes in topography by use of Zernike polynomials enables a general distinction to be made between dynamic alterations in the shape of the cornea itself and the changes in the layer of the tears. The influence of deviations in the shape of the anterior surface of the eye on the retinal image is estimated.

Siedlecki, Damian; Kasprzak, Henryk; Pierscionek, Barbara K.

2007-03-01

56

Black Eye  

Science.gov (United States)

... Eye Health News Consumer Alerts What Is a Black Eye? Tweet Black eye is a phrase used to describe bruising ... dark bruising in the tissue. What Is a Black Eye? Black Eye Symptoms What Causes a Black ...

57

Change-point in stochastic design regression and the bootstrap  

CERN Document Server

In this paper we study the consistency of different bootstrap procedures for constructing confidence intervals (CIs) for the unique jump discontinuity (change-point) in an otherwise smooth regression function in a stochastic design setting. This problem exhibits nonstandard asymptotics and we argue that the standard bootstrap procedures in regression fail to provide valid confidence intervals for the change-point. We propose a version of smoothed bootstrap, illustrate its remarkable finite sample performance in our simulation study, and prove the consistency of the procedure. The $m$ out of $n$ bootstrap procedure is also considered and shown to be consistent. We also provide sufficient conditions for any bootstrap procedure to be consistent in this scenario.

Seijo, Emilio

2011-01-01

58

Design and implementation of a real time and train less eye state recognition system  

Science.gov (United States)

Eye state recognition is one of the main stages of many image processing systems such as driver drowsiness detection system and closed-eye photo correction. Driver drowsiness is one of the main causes in the road accidents around the world. In these circumstances, a fast and accurate driver drowsiness detection system can prevent these accidents. In this article, we proposed a fast algorithm for determining the state of an eye, based on the difference between iris/pupil color and white area of the eye. In the proposed method, vertical projection is used to determine the eye state. This method is suitable for hardware implementation to be used in a fast and online drowsiness detection system. The proposed method, along with other needed preprocessing stages, is implemented on Field Programmable Gate Array chips. The results show that the proposed low-complex algorithm has sufficient speed and accuracy, to be used in real-world conditions.

Dehnavi, Mohammad; Eshghi, Mohammad

2012-12-01

59

Change point analysis and assessment : An integrated methodological design  

DEFF Research Database (Denmark)

The aim of this article is to develop an analytical framework for studying processes such as continuous innovation and business development in high-tech SME clusters that transcends the traditional qualitative-quantitative divide. The article's key contribution is the conceptual integration of four existing and well-recognised but separate approaches to studying events, processes, and change, namely change-point analysis (CPA), event-history analysis (EHA), critical-incident technique (CIT), and sequence analysis (SA) into a single design framework which is especially useful for studying complex and long-term or ongoing processes.

Müller, Sabine; Neergaard, Helle

2011-01-01

60

The Tromsø Eye Study : study design, methodology and results on visual acuity and refractive errors  

DEFF Research Database (Denmark)

Purpose:â?? To describe the study design and methodology of the Tromsø Eye Study (TES), and to describe visual acuity and refractive error in the study population. Methods:â?? The Tromsø Eye Study is a sub-study of the Tromsø Study, a population-based multipurpose longitudinal study in the municipality of Tromsø, Norway. The Tromsø Eye Study was a part of the sixth survey of the Tromsø Study, conducted from October 2007 through December 2008. The eye examination included information on self-reported eye diseases, assessment of visual acuity and refractive errors, retinal photography and optical coherence tomography. Retinal images were graded for diabetic retinopathy and age-related macular degeneration, and with computer-assisted measurements of arteriolar and venular diameters. In addition, TES researchers have access to the large comprehensive Tromsø Study database including physical examination results, carotid artery ultrasound, electrocardiogram, bone densitometry, cognitive tests, questionnaires, DNA, blood and urine samples and more from the present and the five previous surveys. Results:â?? Visual acuity was assessed in 6459 subjects and refraction in 6566 subjects aged 38-87â??years. Snellen visual acuity

Bertelsen, Geir; Erke, Maja G

2013-01-01

 
 
 
 
61

Pointing and spectral assignemnt design and control for MERTIS  

Science.gov (United States)

The development of MERTIS, a miniaturized thermal infrared imaging spectrometer onboard of ESA's cornerstone mission BepiColombo to Mercury has been completed. Qualification of the design is followed by the calibration of the instrument showing up first results of the technology used. Based on subsequent viewing of different targets including on-board calibration sources the push-broom instrument will use a 2-dimensional bolometer detector to provide spatial and spectral information. Here repetition accuracy of pointing and spectral assignment is supported by the design of instrument components under the restriction of limited resources. Additionally a concept of verification after launch and cruise phase of the mission was developed. The article describes how this has been implemented and what the results under environment testing are.

Walter, I.; Säuberlich, T.; Lieder, M.; Rataj, M.; Driescher, H.; Helbert, J.; Hiesinger, H.

2013-09-01

62

Design considerations for optical pointing and scanning mechanisms  

Science.gov (United States)

Optical pointing and scanning mechanisms require inter-related optical, mechanical and electrical engineering and manufacturing disciplines. Such devices are employed in extremely diversified fields of photographic imaging, forward looking infrared (FLIR) systems, laser projection displays (LPD), target acquisition, aerial reconnaissance, remote sensing, and free space laser telecom. The degrees of freedom commonly applied include rotary scanning, raster and vector scanning, and limited angle gimbals. Support systems include flexures, ball bearings, and gas bearings. The performance of the optical payload supported by the pointing or scanning mechanism is paramount and dominates the process of materials selection, structural analysis, actuator selection, and control system development. This paper introduces the tradeoffs among range and type of motion, actuator types, angular sensor types, bearing types, and control systems applied to these types of systems. Actual product design and performance data is presented for a high-speed rotary scanner, a fast "nodding" scanner for a FLIR, a flexure supported fast steering mirror (FSM), and several ball bearing and a gas bearing gimbal designs.

Sweeney, Michael N.; Erdelyi, Emery; Ketabchi, Mehrdad; Kent, Blanche

2003-10-01

63

Fast ignition integrated experiments and high-gain point design  

Science.gov (United States)

Integrated fast ignition experiments were performed at ILE, Osaka, and LLE, Rochester, in which a nanosecond driver laser implodes a deuterated plastic shell in front of the tip of a hollow metal cone and an intense ultrashort-pulse laser is injected through the cone to heat the compressed plasma. Based on the initial successful results of fast electron heating of cone-in-shell targets, large-energy short-pulse laser beam lines were constructed and became operational: OMEGA-EP at Rochester and LFEX at Osaka. Neutron enhancement due to heating with a ?kJ short-pulse laser has been demonstrated in the integrated experiments at Osaka and Rochester. The neutron yields are being analysed by comparing the experimental results with simulations. Details of the fast electron beam transport and the electron energy deposition in the imploded fuel plasma are complicated and further studies are imperative. The hydrodynamics of the implosion was studied including the interaction of the imploded core plasma with the cone tip. Theory and simulation studies are presented on the hydrodynamics of a high-gain target for a fast ignition point design.

Shiraga, H.; Nagatomo, H.; Theobald, W.; Solodov, A. A.; Tabak, M.

2014-05-01

64

The Modular Point Design for Heavy Ion Fusion  

International Nuclear Information System (INIS)

We report on an ongoing study on modular Heavy Ion Fusion drivers. The modular driver is characterized by tens (? 20) nearly identical induction linacs, each carrying a single high current beam. In this scheme, the Integrated Research Experiment (IRE) can be one of the full size induction linacs. Hence, this approach offers significant advantages in terms of driver development path. For beam transport, these modules use solenoids which are capable of carrying high line charge densities, even at low energies. A new injector concept allows compression of the beam to high line densities right at the source. The final drift compression is performed in a plasma, in which the large repulsive space charge effects are neutralized. Finally, the beam is transversely compressed onto the target, using either external solenoids or current-carrying channels (in the Assisted Pinch Mode of beam propagation). We will report on progress towards a self-consistent point design from injector to target. Considerations of driver architecture, chamber environment as well as the methodology for meeting target requirements of spot size, pulse shape and symmetry will also be described. Finally, some near-term experiments to address the key scientific issues will be discussed

2005-01-01

65

Trajectory design for space missions to libration point L2.  

Science.gov (United States)

This work is focused on the detection and computation of "free" transfer trajectories from parking orbits around the Earth to quasiperiodic orbits around the collinear libration point L(2), in the Sun-Earth system; no correction or insertion maneuvers into the final orbits have been considered. The circular restricted three-body problem is the mathematical model used to describe the motion of a spacecraft, in the gravitational field of the two primaries, computed by integrating the nonlinearized equations of motion. A shooting method has been designed and developed to determine the increment of velocity required for the perigee maneuver, which injects a spacecraft into its transfer trajectory: first the velocity boundary for the Earth escape/capture condition is detected and then an iterative bisection method is applied until the burnout velocity, tangential to the parking orbit, leads the spacecraft to its final Lissajous orbit. For a launch from Kourou at local noon, Ariane5 GTO and Soyuz GTO "equivalent" have been studied and compared, considering fuel minimization for the transfer maneuver and general mission constraints, as maximum excursion of the final Lissajous orbit from the ecliptic plane and eclipses avoidance during the mission. This analysis highlights advantages and drawbacks of various parking orbits. Mission goals are the key factor for the tradeoff among orbit selection, launch options, and the other constraints, fixed by mission requirements. PMID:16510417

Di Salvo, Alessio

2005-12-01

66

LED eye safety considerations in the design of iris capture systems  

Science.gov (United States)

We have developed a standoff iris biometrics system for improved usability in access-control applications. The system employs an eye illuminator, which is composed of an array of encapsulated near-infrared light emitting diodes (NIRLEDs), which are triggered at the camera frame rate for reduced motion blur and ambient light effects. Neither the standards / recommendations for NIR laser and lamp safety, nor the LED-specific literature address all the specific aspects of LED eye-safety measurement. Therefore, we established exposure limit criteria based on a worst-case scenario combining the following: the CIE/ANSI standard/recommendations for exposure limits; concepts for maximum irradiance level and for strobing from the laser safety standards; and ad-hoc rules minimizing irradiance on the fovea, for handling LED arrays, and for LED mounting density. Although our system was determined as eye safe, future variants may require higher exposure levels and lower safety margins. We therefore discuss system configuration for accurate LED radiometric measurement that will ensure reliable eye-safety evaluation. The considerations and ad hoc rules described in this paper are not, and should not be treated as safety recommendations.

Abramovich, Gil; Wheeler, Frederick W.

2011-05-01

67

Design for Optimum Wave Conditions, Dana Point Harbor, Dana Point, California. Hydraulic Model Investigation.  

Science.gov (United States)

The entire Dana Point area that will be enclosed by Dana Point Harbor and sufficient adjacent coastline and offshore bathymetry to permit accurate simulation of storm-wave action were reproduced in a 1:100-scale hydraulic model equipped with wave-generati...

H. B. Wilson

1966-01-01

68

Studying nanostructured nipple arrays of moth eye facets helps to design better thin film solar cells.  

Science.gov (United States)

Nipples on the surface of moth eye facets exhibit almost perfect broadband anti-reflection properties. We have studied the facet surface micro-protuberances, known as corneal nipples, of the chestnut leafminer moth Cameraria ohridella by atomic force microscopy, and simulated the optics of the nipple arrays by three-dimensional electromagnetic simulation. The influence of the dimensions and shapes of the nipples on the optics was studied. In particular, the shape of the nipples has a major influence on the anti-reflection properties. Furthermore, we transferred the structure of the almost perfect broadband anti-reflection coatings to amorphous silicon thin film solar cells. The coating that imitates the moth-eye array allows for an increase of the short circuit current and conversion efficiency of more than 40%. PMID:22155981

Dewan, Rahul; Fischer, Stefan; Meyer-Rochow, V Benno; Özdemir, Yasemin; Hamraz, Saeed; Knipp, Dietmar

2012-03-01

69

Studying nanostructured nipple arrays of moth eye facets helps to design better thin film solar cells  

International Nuclear Information System (INIS)

Nipples on the surface of moth eye facets exhibit almost perfect broadband anti-reflection properties. We have studied the facet surface micro-protuberances, known as corneal nipples, of the chestnut leafminer moth Cameraria ohridella by atomic force microscopy, and simulated the optics of the nipple arrays by three-dimensional electromagnetic simulation. The influence of the dimensions and shapes of the nipples on the optics was studied. In particular, the shape of the nipples has a major influence on the anti-reflection properties. Furthermore, we transferred the structure of the almost perfect broadband anti-reflection coatings to amorphous silicon thin film solar cells. The coating that imitates the moth-eye array allows for an increase of the short circuit current and conversion efficiency of more than 40%.

2012-03-01

70

Dynamics and mission design near libration points, advanced methods for triangular points  

Digital Repository Infrastructure Vision for European Research (DRIVER)

The final objective of this work is to understand, analyze and compute the kinds of motion that appear on a vicinity (may be a large vicinity) of the geometrically defined equilateral points of the Earth-Moon system, as a source of possible nominal orbits for future space missions.

Go?mez, Gerard; Jorba, Angel; Masdemont Soler, Josep; Simo? Torres, Carlos

2000-01-01

71

PORTRAYING THE NORDIC DESIGN FROM AN INSIDE POINT OF VIEW  

Directory of Open Access Journals (Sweden)

Full Text Available Scandinavian Design. Alternative Histories is a rather technical but an easy-to-read academic work, focusing mainly on the often ignored complexity of the theme, introducing various fresh perspectives to the subject. The authors try to provide the reader with a radically different vision, constructed by clarifying many of the persistent myths of Scandinavian design.

Aida Puente Toraño

2012-01-01

72

Eye Examinations  

Science.gov (United States)

... eye care professional to examine the retina and optic nerve. Credit: National Eye Institute, National Institutes of Health Ref#: EE70 72 dpi ( ... eye care professional to examine the retina and optic nerve. Credit: National Eye Institute, National Institutes of Health Ref#: EE69 72 dpi ( ...

73

Eyes, Bulging  

Science.gov (United States)

... eye pain In people who have recently had eye surgery or an eye injury or who have a bleeding disorder CT ... and pupil). Sometimes if lubrication is not sufficient, surgery to provide better coverage of the eye surface or to reduce bulging may be needed. ...

74

Design and Implementation of IEEE-754 Addition and Subtraction for Floating Point Arithmetic Logic Unit  

Directory of Open Access Journals (Sweden)

Full Text Available This paper describes the FPGA implementation of a Decimal Floating Point (DFP adder/subtractor using IEEE 754-2008 format. In this paper we describe an efficient implementation of an IEEE 754 single precision Standard for Binary Floating-Point Arithmetic to include specifications for decimal floating-point arithmetic. As processor support for decimal floating-point arithmetic emerges, it is important to investigate efficient algorithms and hardware designs for common decimal floating-point arithmetic algorithms. This paper presents novel designs for a decimal floating-point addition and subtraction. They are fully synthesizable hardware descriptions in VERILOG. Each one is presented for high speed computing.

V.VINAY CHAMKUR , Chetana.R

2012-06-01

75

Comparison of refractive error in eyes with vitrectomy, silicone oil tamponade finished phacoemulsification and intraocular lens implantation in different time point  

Directory of Open Access Journals (Sweden)

Full Text Available AIM: To compare the refractive error in eyes with vitrectomy and silicone oil tamponade finished phacoemulsification and intraocular lens(IOLimplantation in different time point. METHODS: Fifty-one patients(51 eyeswith vitrectomy and silicone oil tamponade performed phacoemulsification and IOL implantation were retrospectively analysed during 2009-01/2011-12 and divided into three groups by different time point of phacoemulsification and IOL implantation. There were 17 cases in A group performed silicone oil tamponade after vitrectomy combined with phacoemulsification and intraocular lens IOL implantation, silicone oil removal was performed after 3-6 months; 13 cases in B group performed silicone oil removal combined with phacoemulsification and IOL implantation; 21 cases in C group of scheduled phacoemulsification and IOL implantation after silicone oil removal, refractive error was compared 3months postoperatively. RESULTS: The average absolute value of refractive error was 0.873±0.256D in A group, 0.828±0.134D in B group, 0.473±0.121D in C group. There was no statistical significant difference compared with A group and B group(P>0.05, but there was statistical significant difference compared with C group and A, B group(PCONCLUSION: Axial length was measured by A Scan ultrasonograph. The refractive error was small in group of phacoemulsification and IOL implantation after silicone oil removal relatively.

Qian Shi

2013-06-01

76

Design and development of a ferroelectric micro photo detector for the bionic eye  

Science.gov (United States)

Driven by no effective therapy for Retinitis Pigmentosa and Age Related Macular Degeneration, artificial vision through the development of an artificial retina that can be implanted into the human eye, is being addressed by the Bionic Eye. This dissertation focuses on the study of a photoferroelectric micro photo detector as an implantable retinal prosthesis for vision restoration in patients with above disorders. This implant uses an electrical signal to trigger the appropriate ocular cells of the vision system without resorting to wiring or electrode implantation. The research work includes fabrication of photoferroelectric thin film micro detectors, characterization of these photoferroelectric micro devices as photovoltaic cells, and Finite Element Method (FEM) modeling of the photoferroelectrics and their device-neuron interface. A ferroelectric micro detector exhibiting the photovoltaic effect (PVE) directly adds electrical potential to the neuron membrane outer wall at the focal adhesion regions. The electrical potential then generates a retinal cell membrane potential deflection through a newly developed Direct-Electric-Field-Coupling (DEFC) model. This model is quite different from the traditional electric current model because instead of current directly working on the cell membrane, the PVE current is used to generate a localized high electric potential in the focal adhesion region by working together with the anisotropic high internal impedance of ferroelectric thin films. General electrodes and silicon photodetectors do not have such anisotropy and high impedance, and thus they cannot generate DEFC. This mechanism investigation is very valuable, because it clearly shows that our artificial retina works in a way that is totally different from the traditional current stimulation methods.

Song, Yang

77

THE INFLUENCE OF EYES AND BRAIN BEHIND "ARTERMA TOOL" IN FIRST PERSON POINT OF VIEW INTERFACE OF GAMES  

Directory of Open Access Journals (Sweden)

Full Text Available The application of point of view (POV in electronic games has been vastly applied and fast becoming a favorite among electronic games (EG players particularly in games of action genre like warfare games. While allowing the users to experience the character first-hand, POV has its limitations for users. One example of the problems is the difficulty to anticipate the direction an attack by the enemy from a POV blindspot. Another problem is the difficulty to prepare a strategy. Some players become “somewhat dizzy” and eventually give up the game. This paper elaborates on the development of a framework for interactive montage on EG software interface using ArTerma tools and how the ArTerma tool works in the POV interface. Therefore, to accomplish the development of ArTerma tools, (A1(DDI2E3 model is used. In (A1(DDI2E3 model usage, ADDIE model is combined with other model concept such as “Diegesis Spatiality” concept Model, Frame concept model, and Mental concept model has been employed along side an elaboration on case studies. The study hopes that the developed a new model as well as support tool can help improve future EGs.

Irma Shayana Samaden

2014-10-01

78

Eye Protection  

Digital Repository Infrastructure Vision for European Research (DRIVER)

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.

Pashby, Tom

1986-01-01

79

Designing Low-Cost Cryptographic Hardware for Wired- or Wireless Point-to-Point Connections  

Science.gov (United States)

Science and industry consider non classical cryptographic technologies to provide alternative security solutions. They are motivated by strong restrictions as they are often present in embedded security scenarios and in application such as battery powered embedded systems and RFID devices with often severe resource limitations. We investigate the implementation of a low hardware complexity cryptosystem for lightweight (authenticated) symmetric key exchange, based on two new Tree Parity Machine Rekeying Architectures (TPMRAs). This work significantly extends and optimizes (number of gates) previously published results on TPMRAs. We evaluate characteristics of standardcell ASIC design realizations as IP-core in 0.18-CMOS technology and an implementation into a standard bus controller with security features.

Wallner, Sebastian

80

Application of two procedures for dual-point design of transonic airfoils  

Science.gov (United States)

Two dual-point design procedures were developed to reduce the objective function of a baseline airfoil at two design points. The first procedure to develop a redesigned airfoil used a weighted average of the shapes of two intermediate airfoils redesigned at each of the two design points. The second procedure used a weighted average of two pressure distributions obtained from an intermediate airfoil redesigned at each of the two design points. Each procedure was used to design a new airfoil with reduced wave drag at the cruise condition without increasing the wave drag or pitching moment at the climb condition. Two cycles of the airfoil shape-averaging procedure successfully designed a new airfoil that reduced the objective function and satisfied the constraints. One cycle of the target (desired) pressure-averaging procedure was used to design two new airfoils that reduced the objective function and came close to satisfying the constraints.

Mineck, Raymond E.; Campbell, Richard L.; Allison, Dennis O.

1994-01-01

 
 
 
 
81

Dry Eye  

Science.gov (United States)

... in thyroid disease when the eye protrudes forward; cosmetic surgery, if the eyelids are opened too widely. Frequently ... disease when the eye protrudes forward or after cosmetic surgery if the eyelids are opened too widely, dry ...

82

Eye Coordination  

Science.gov (United States)

... Good Vision For Life Infants Children Adults Seniors Caring for Your Vision Eye & Vision Exams Contact Lenses Diet and Nutrition UV Protection Resources for Teachers 3D Vision & Eye Health Classroom Exercises How Your ...

83

Dry eyes  

Science.gov (United States)

... often rheumatoid arthritis or other joint disorder Previous eye surgery ... taking any medications? Which ones? Have you had surgery or an injury to your eyes or nose? Do you have allergies? Have you ...

84

Amblyopia: Lazy Eye Treatment  

Science.gov (United States)

... Eyes & the Sun Eye Health News Consumer Alerts Amblyopia: Lazy Eye Treatment Tweet Lazy eye correction or treatment should ... Amblyopia: Lazy Eye Diagnosis Amblyopia: Lazy Eye Treatment Lazy eye patch treatment If refractive amblyopia is a problem, ...

85

Design and Analysis of Lightweight Pointing Mirror Used in Space Camera  

Energy Technology Data Exchange (ETDEWEB)

Pointing mirror is one of the critical components of space camera to get earth images. Lightweighting design and simulation analysis of mirror play a major role in weight minimization and performance optimization of camera. Based on concept of design of experiments, this paper introduces a method combined curve fit with finite element simulation analysis and optimization to the lightweighting design of pointing mirror, as well as demonstrates design procedure, performance analysis and checkout of mirror. The results indicate that this method has good maneuverability and utility. This technique could be applied to lightweighting design of mirror which has a regular topological structure.

Guo, S W; Zhang, G Y; Wang, W Y; Zhao, X Z [School of Mechanical and Electrical Engineering, Harbin Institute of Technology, Harbin 150001 (China)

2006-10-15

86

Design and construction progress on Gentilly 2, Cordoba, Point Lepreau, and Wolsung projects  

International Nuclear Information System (INIS)

Gentilly 2, Point Lepreau, Cordoba and Wolsung are the first 600 MW CANDU nuclear generating stations to be built. Progress in their construction and in the remaining design work for these stations is discussed. (LL)

1980-06-18

87

New Approach to Design Networks Having a Prescribed Driving-Point Impedance in Brune Fashion.  

Science.gov (United States)

The design of networks having a prescribed driving-point impedance as a Brune one-port is well known and discussed in almost any textbook on linear and passive network synthesis. However, this classical design procedure is tedious, the more the degrees of...

K. H. Haase

1970-01-01

88

Design and development of injection molded Fresnel lenses for point-focus photovoltaic systems  

Energy Technology Data Exchange (ETDEWEB)

A summary of work performed on a method of injection molding an 80% efficient point-focus Fresnel lens is presented. A current optical design for compression molded lenses yields a 68.5% efficiency when translated directly to injection molding. An optical design optimized for injection molding, with a mold and process developed for high efficiency Fresnel lenses, yields an 82% efficiency.

Grendol, C.L.

1987-05-01

89

Elimination of less informative design points in regression models with a known or parametrized covariance function  

Digital Repository Infrastructure Vision for European Research (DRIVER)

We consider a regression model E[y(x)] = eta(theta, x) where x is a design point taken from a finite design space X. The covariance of observations is Cov[y(x), y(x*)] = C(x, x*, beta). Here, theta, beta are unknown vector parameters. The quality of the ML estimators of and is measured by optimality criteria applied on the Fisher information matrix taken at a fixed theta, beta (= local optimality). In this paper we give formulae to identify the design points which have little influence on thi...

2005-01-01

90

Shielding of the Final Focusing System in the Robust Point Design  

International Nuclear Information System (INIS)

The Heavy Ion Fusion Virtual National Laboratory (HIF-VNL) recently initiated an effort to reach an updated, self-consistent, integrated point design for a thick-liquid inertial fusion energy power plant. We call this design the Robust Point Design. As part of this effort, the shielding design of the final focusing system has been evaluated, in an iterative fashion, with other elements of the design. The present work reports on the status of the shielding design from the perspectives of superconductor/insulator radiation lifetimes, recirculating power needed to counter nuclear heating, and neutron activation, which affects both system maintainability and waste management. Models used herein include the last three focusing magnets, and a full, three-dimensional model for the target chamber. Analyses have been performed for 9-by-9 beam arrays, with a total of 120 beams (60 per side). Results and directions for future work are presented

2003-09-01

91

Eye pain  

Science.gov (United States)

... irritation, or injury such as a corneal abrasion ) Eye surgery Glaucoma Migraines Sinus problems Stye Viral infections such ... an immune system deficiency You have had recent surgery You have ... pressure in the eyes that does not go away -- particularly if it ...

92

Reliability of impingement sampling designs: An example from the Indian Point station  

International Nuclear Information System (INIS)

A 4-year data base (1976-1979) of daily fish impingement counts at the Indian Point electric power station on the Hudson River was used to compare the precision and reliability of three random-sampling designs: (1) simple random, (2) seasonally stratified, and (3) empirically stratified. The precision of daily impingement estimates improved logarithmically for each design as more days in the year were sampled. Simple random sampling was the least, and empirically stratified sampling was the most precise design, and the difference in precision between the two stratified designs was small. Computer-simulated sampling was used to estimate the reliability of the two stratified-random-sampling designs. A seasonally stratified sampling design was selected as the most appropriate reduced-sampling program for Indian Point station because: (1) reasonably precise and reliable impingement estimates were obtained using this design for all species combined and for eight common Hudson River fish by sampling only 30% of the days in a year (110 d); and (2) seasonal strata may be more precise and reliable than empirical strata if future changes in annual impingement patterns occur. The seasonally stratified design applied to the 1976-1983 Indian Point impingement data showed that selection of sampling dates based on daily species-specific impingement variability gave results that were more precise, but not more consistently reliable, than sampling allocations based on the variability of all fish species combined. 14 refs., 1 fig., 6 tabs

1988-01-01

93

Design and evaluation of aircraft heat source systems for use with high-freezing point fuels  

Science.gov (United States)

The objectives were the design, performance and economic analyses of practical aircraft fuel heating systems that would permit the use of high freezing-point fuels on long-range aircraft. Two hypothetical hydrocarbon fuels with freezing points of -29 C and -18 C were used to represent the variation from current day jet fuels. A Boeing 747-200 with JT9D-7/7A engines was used as the baseline aircraft. A 9300 Km mission was used as the mission length from which the heat requirements to maintain the fuel above its freezing point was based.

Pasion, A. J.

1979-01-01

94

Using eye-tracking methodology in consumer science  

DEFF Research Database (Denmark)

Eye-tracking methodology will soon be mature enough to become a standard tool in consumer science. The workshop will begin with a short overview of the perceptual and attention processes that can be measured by eye-tracking. The available hardware and software will be compared, and typical experimental designs will be discussed that can be recommended for eye-tracking studies in consumer science. The application potential will then be demonstrated in four case presentations, focusing on different product categories (from dairy products to alcoholic beverages), measurement contexts (laboratory versus point of purchase) and study goals (appearance studies, package design, identification of food choice motives). Furthermore, the presentations will discuss how different components of attention can be distinguished based on eye-tracking data (stimulus-driven versus task-driven processes) and how the explanatory power of eye-tracking studies can be boosted by combining eye-tracking with other methodologies (shelf simulations, choice experiments, neuroimaging techniques). The workshop will conclude with an open discussion in which participants can consult the presenters on the applicability of eye-tracking methods in their own research.

Bialkova, S.; Mueller Loose, Simone

95

Eye dilation  

Science.gov (United States)

The iris is the colored part of the eye. The pupil is the dark circle in the middle of the iris. The iris causes the pupil to expand or contract depending on the amount of light in a given area. Once light passes through the pupil, a structure called the lens that is directly behind the pupil focuses the light at the back of the eye. The optic nerve, located at the back of the eye, takes the focused message and relays it to the brain where it is processed into an image.

Greyson Orlando (None;)

2006-12-11

96

Thyroid Eye Disease: Protruding, Irritated Eyes  

Science.gov (United States)

... eyes and double vision can be improved with eye muscle surgery to reposition the enlarged muscles that control eye ... completely eliminate all of the consequences of thyroid eye disease, surgery to correct these conditions is generally successful in ...

97

Unbalanced and Minimal Point Equivalent Estimation Second-Order Split-Plot Designs  

Science.gov (United States)

Restricting the randomization of hard-to-change factors in industrial experiments is often performed by employing a split-plot design structure. From an economic perspective, these designs minimize the experimental cost by reducing the number of resets of the hard-to- change factors. In this paper, unbalanced designs are considered for cases where the subplots are relatively expensive and the experimental apparatus accommodates an unequal number of runs per whole-plot. We provide construction methods for unbalanced second-order split- plot designs that possess the equivalence estimation optimality property, providing best linear unbiased estimates of the parameters; independent of the variance components. Unbalanced versions of the central composite and Box-Behnken designs are developed. For cases where the subplot cost approaches the whole-plot cost, minimal point designs are proposed and illustrated with a split-plot Notz design.

Parker, Peter A.; Kowalski, Scott M.; Vining, G. Geoffrey

2007-01-01

98

Your Eyes  

Science.gov (United States)

... with a clear, jelly-like material called the vitreous humor. Ever touch toy eyeballs in a store? Sometimes ... made to feel like they're filled with vitreous humor. In a real eye, after light passes through ...

99

An integrated mechanical design concept for the final focusingregion for the HIF point design  

Energy Technology Data Exchange (ETDEWEB)

A design study was undertaken to develop a ''first cut'' integrated mechanical design concept of the final focusing region for a conceptual IFE power plant that considers the major issues which must be addressed in an integrated driver and chamber system. The conceptual design in this study requires a total of 120 beamlines located in two conical arrays attached on the sides of the target chamber 180 degrees apart. Each beamline consists of four large-aperture superconducting quadrupole magnets and a dipole magnet. The major interface issues include radiation shielding and thermal insulation of the superconducting magnets; reaction of electromagnetic loads between the quadrupoles; alignment of the magnets; isolation of the vacuum regions in the target chamber from the beamline, and assembly and maintenance.

Brown, T.; Sabbi, G.-L.; Barnard, J.J.; Heitzenroeder, P.; Chun,J.; Schmidt, J.; Yu, S.S.; Peterson, P.F.; Abbott, R.P.; Callahan, D.A.; Latkowski, J.F.; Logan, B.G.; Meier, W.R.; Pemberton, S.J.; Rose, D.V.; Sharp, W.M.; Welch, D.R.

2002-11-21

100

The design, development and qualification of a lightweight antenna pointing mechanism  

Science.gov (United States)

This paper describes the design, development, and qualification of a new lightweight and compact Antenna Pointing Mechanism (APM). The APM was specially designed to meet the stringent mass, envelope, and environmental requirements of OFFEQ experimental satellite. During the development phase, some problems were encountered with the brushless DC motors, slip ring contact resistance, and bearing drag torque. All of these problems were resolved, and two APM units have been operating successfully in orbit since April, 1995.

Shmulevitz, M.; Halsband, A.

1996-01-01

 
 
 
 
101

Design of 16-point Radix-4 Fast Fourier Transform in 0.18µm CMOS Technology  

Directory of Open Access Journals (Sweden)

Full Text Available This paper introduces detail design of semi-custom CMOS Fast Fourier Transform (FFT architecture for computing 16-point radix-4 FFT. FFT is one of the most widely used algorithms in digital signal processing. It is used in many signal processing and communication application as an important block for various multi-carrier systems such as for WLAN (Wireless local area network. This paper describes the design of an ASIC (Application Specific Integrated Circuit CMOS FFT processor for 16-point radix-4 complex FFT computation, realized utilizing 0.18µm standard CMOS technology. Fixed point data format is preferred in comparison of floating point data format for a shorter dynamic range and reduced hardware utilization; thus, catering to the needs of portability. Furthermore, computations results at particular stage are rounded to avoid overflow issue and to be stored in register. The computation speed of the design is observed to be 50MHz after the synthesis process. Compared to traditional radix-4 algorithm the architecture proposed for 16-point FFT results in 1.73% of power saving and 5.5% of area reduction.

Siva K. Palaniappan

2007-01-01

102

Hinkley Point 'C' power station public inquiry: proof of evidence on design and safety  

International Nuclear Information System (INIS)

A public inquiry has been set up to examine the planning application made by the Central Electricity Generating Board (CEGB) for the construction of a 1200 MW Pressurized Water Reactor power station at Hinkley Point (Hinkley Point ''C'') in the United Kingdom. The policy is to replicate the Sizewell ''B'' PWR design. The Hinkley Point ''C'' design is described indicating where changes in the Sizewell ''B'' design have been made to accommodate site differences. These are associated with the civil engineering construction and some of the electrical systems and do not affect the safety case. External hazards differ from site to site and the effect on the safety case of those specific to Hinkley Point are examined. The Chernobyl accident and the assessment of the United Kingdom PWR which was carried out subsequently are reviewed. The assessment indicated that no changes in the Sizewell ''B'' design and safety case were called for as a result of this accident; accident management developments are also reviewed, however. The CEGB's approach to minimizing occupational radiation doses is described. (UK)

1988-01-01

103

Design and Principles of Linear Accelerators and Colliders: Focusing at Interaction Point  

CERN Document Server

This document is part of Subvolume C 'Accelerators and Colliders' of Volume 21 'Elementary Particles' of Landolt-Börnstein - Group I 'Elementary Particles, Nuclei and Atoms'. It contains the the Section '7.7 Focusing at Interaction Point' of the Chapter '7 Design and Principles of Linear Accelerators and Colliders'.

Seryi, A

2013-01-01

104

Fuzzy Controller Design Using FPGA for Photovoltaic Maximum Power Point Tracking  

Directory of Open Access Journals (Sweden)

Full Text Available The cell has optimum operating point to be able to get maximum power. To obtain Maximum Power from photovoltaic array, photovoltaic power system usually requires Maximum Power Point Tracking (MPPT controller. This paper provides a small power photovoltaic control system based on fuzzy control with FPGA technology design and implementation for MPPT. The system composed of photovoltaic module, buck converter and the fuzzy logic controller implemented on FPGA for controlling on/off time of MOSFET switch of a buck converter. The proposed maximum power point tracking controller for photovoltaic system is tested using model designed by Matlab/Simulink program with graphical user interface (GUI for entering the parameters of any array model using information from its datasheet, Simulation and experimental results show that performance of the fuzzy controller with FPGA in a maximum power tracking of a photovoltaic array can be made use of in several photovoltaic products and obtain satisfied result.

Basil M Hamed

2012-06-01

105

LASIK - Laser Eye Surgery  

Medline Plus

Full Text Available Eye Health Lifestyle Topics Preventing Eye Injuries Healthy Eyes During Pregnancy Computer Usage & Eye Strain Maintaining Your ... Next Page: Alternative Refractive Surgery Procedures Find An Eye M.D. Enter zip code here Search by ...

106

Smoking and Eye Health  

Science.gov (United States)

... Eyes & the Sun Eye Health News Consumer Alerts Smoking and Eye Health Tweet Eye Health Lifestyle Topics ... prevent pollen from getting in your eyes. No Smoking Smoking increases the risk of developing cataracts – quit ...

107

What Is Dry Eye?  

Medline Plus

Full Text Available ... Sun Eye Health News Consumer Alerts What Is Dry Eye? Tweet When you blink, a film of tears ... good vision would not be possible. What Is Dry Eye? Causes of Dry Eye Dry Eye Symptoms Who ...

108

LASIK - Laser Eye Surgery  

Medline Plus

Full Text Available ... Eye Injuries Healthy Eyes During Pregnancy Computer Usage & Eye Strain Maintaining Your Sight with Diabetes Sports and Eye Protection Eyesight Risks for Smokers Veterans & Eye Health ...

109

Compact reversed-field pinch reactors (CRFPR): sensitivity study and design-point determination  

International Nuclear Information System (INIS)

If the costing assumptions upon which the positive assessment of conventional large superconducting fusion reactors are based proves overly optimistic, approaches that promise considerably increased system power density and reduced mass utilization will be required. These more compact reactor embodiments generally must operate with reduced shield thickness and resistive magnets. Because of the unique, magnetic topology associated with the Reversed-Field Pinch (RFP), the compact reactor embodiment for this approach is particularly attractive from the viewpoint of low-field resistive coils operating with Ohmic losses that can be made small relative to the fusion power. A comprehensive system model is developed and described for a steady-state, compact RFP reactor (CRFPR). This model is used to select a unique cost-optimized design point that will be used for a conceptual engineering design. The cost-optimized CRFPR design presented herein would operate with system power densities and mass utilizations that are comparable to fission power plants and are an order of magnitude more favorable than the conventional approaches to magnetic fusion power. The sensitivity of the base-case design point to changes in plasma transport, profiles, beta, blanket thickness, normal vs superconducting coils, and fuel cycle (DT vs DD) is examined. The RFP approach is found to yield a point design for a high-power-density reactor that is surprisingly resilient to changes in key, but relatively unknown, physics and systems parameters

1982-01-01

110

Design status of ITER visible/IR outer strike point view  

International Nuclear Information System (INIS)

For ITER visible/IR imaging of the outer strike point from the six upper ports currently assigned, we show an optical design that provides a 4 mm Airy disk at 5 ?m wavelength at the farthest point in the field of view (much smaller in the visible), with as complete toroidal coverage of the vertical target as possible. Plasma and optical effects provide fundamental limits on the performance and design of the system. Some effects involve interactions of the surfaces with the plasma, such as plasma transport and deposition of material on the surfaces to be viewed, plasma damage to those surfaces, and molecular emission by the plasma at IR wavelengths. We discuss a detailed optical design including the endoscope concept, entrance aperture and collection head, relay optics, and camera specifications and performance. We assess integration times for capture of IR emission from surfaces and visible line emission predicted by boundary modeling.

2009-06-15

111

Design status of ITER visible/IR outer strike point view  

Energy Technology Data Exchange (ETDEWEB)

For ITER visible/IR imaging of the outer strike point from the six upper ports currently assigned, we show an optical design that provides a 4 mm Airy disk at 5 mum wavelength at the farthest point in the field of view (much smaller in the visible), with as complete toroidal coverage of the vertical target as possible. Plasma and optical effects provide fundamental limits on the performance and design of the system. Some effects involve interactions of the surfaces with the plasma, such as plasma transport and deposition of material on the surfaces to be viewed, plasma damage to those surfaces, and molecular emission by the plasma at IR wavelengths. We discuss a detailed optical design including the endoscope concept, entrance aperture and collection head, relay optics, and camera specifications and performance. We assess integration times for capture of IR emission from surfaces and visible line emission predicted by boundary modeling.

Lasnier, C.J., E-mail: Lasnier@llnl.go [Lawrence Livermore National Laboratory, Livermore, CA 94550 (United States); Seppala, L.G.; Morris, K.; Fenstermacher, M.E.; Groth, M. [Lawrence Livermore National Laboratory, Livermore, CA 94550 (United States)

2009-06-15

112

Web Design for Multiple Platforms in Microsoft SharePoint 2013  

Digital Repository Infrastructure Vision for European Research (DRIVER)

As mobile devices become more common when surfing the web there is an increasing demand of making web sites adjusted to other devices than computers. One common platform on the web is Microsoft SharePoint. In this report I look into one method of how to develop web sites that work on multiple devices in Microsoft SharePoint. I will be looking into different techniques as separate web sites compared to responsive web design. By exploring the approach of mobile first I try to find a working sol...

Claug, Erik

2013-01-01

113

Design and characterization of an Antenna Pointing Mechanism for on-orbit servicing missions  

Science.gov (United States)

The goal of this work was to (1) define parameters to characterize a pointing mechanism, (2) design a setup to test these parameters and, (3) verify the test methods by comparing the results to the theoretically calculated or independently verified numbers. The verification of the test results was conducted with an in-house built Antenna Pointing Mechanism for on-orbit servicing applications. The test setup was developed to find a method to measure the behavior of a pointing mechanism. This was realized by mounting a Laser pointer on the antenna interface of the mechanism and pointing it towards a two-dimensional Position Sensitive Detector, providing means to resolve small motions, and to derive velocity and acceleration of the mechanism. The results show good correlation for characteristic parameters such as pointing velocity and acceleration, repeatability, resolution and pointing accuracy of the mechanism. In future work this test method will be qualified for and used to compare the performance of the mechanism at different environmental conditions such as vacuum, temperature and microgravity.

Purschke, R.; Hoehn, A.

114

Animals Eyes  

Science.gov (United States)

The Web site from BioMedia (1) is a fascinating look (no pun intended) at the eyes of other animals. Various images of eyeballs link to essays that explain such questions as how animals can see underwater and how many times the eye independently evolved in the animal kingdom. The next site (2) is based on a PBS Nova documentary about nocturnal animals. Visitors can click on an image of an eye to learn more about the animal that uses it to see in the dark. The San Diego Natural History Museum provides the kid-friendly Web site, which does a terrific job of explaining the anatomy and function of different types of eyes (3). The next site, provided by Tufts University, offers photos of how squirrels, sharks, turtles, and bees might see the world compared with human vision (4). Andrew Giger, a neuroscientist working on bee vision at the Australian National University, wrote the program B-EYE for his research. Visitors to his Web site (5) can see what a selection of grey-scale images might look like from a bee's perspective. The next site (6) is provided by about.com, offering a detailed article about bird vision. Similarly, the next Web site from the North American Hunting Retriever Association contains an extensive review of an article that appeared in the Journal of the Veterinary Medical Association about dog vision (7). Finally, the last site is a page from Micscape - the online monthly magazine of Microscopy UK - showing how the eyes of various mollusks look under the microscope (8).

Sohmer, Rachel.

2002-01-01

115

LASIK - Laser Eye Surgery  

Medline Plus

Full Text Available Eye Health Lifestyle Topics Preventing Eye Injuries Healthy Eyes During Pregnancy Computer Usage & Eye Strain Maintaining Your Sight with ... Eye Protection Eyesight Risks for Smokers Veterans & Eye Health More Lifestyle Topics > EyeSmart Tips Smoking and AMD ...

116

LASIK - Laser Eye Surgery  

Medline Plus

Full Text Available Eye Health Lifestyle Topics Preventing Eye Injuries Healthy Eyes During Pregnancy Computer Usage & Eye Strain Maintaining Your Sight with ... Eye Protection Eyesight Risks for Smokers Veterans & Eye Health More Lifestyle Topics > EyeSmart Tips Preserve Your Child's ...

117

At-sea test system point design for a one-third scale cold water pipe  

Energy Technology Data Exchange (ETDEWEB)

One step in the development of the technology for Ocean Thermal Energy Conversion (OTEC) Cold Water Pipes (CWP) is the at-sea testing of a fiberglass reinforced plastic nominal 10-foot diameter pipe. A design procedure and criteria for developing test hardware by scaling down a 30-foot diameter OTEC 10/40 MW Pilot Plant CWP design are presented. An example point design for the pipe, instrumentation to be used during the at-sea tests, and methods for selecting the support platform and mooring are described. The design considered starts with a scale model of a larger prototype, and then is modified to address the problems of fabrication and of survivability and handling during the 1/3rd scale model tests.

Sutherland, W.H. (ed.)

1979-12-01

118

Design and development of a laminated Fresnel lens for point-focus PV systems. Phase II  

Energy Technology Data Exchange (ETDEWEB)

A laminated glass-plastic lens parquet using injection molded point focus Fresnel lenses is described. The second phase of a program aimed at investigating the cost effectiveness of a glass-plastic concentrator lens assembly is reported. The first phase dealt with the development of a first generation lens design, the selection of the preferred glass coverplate and glass-to-lens adhesive and initial injection molding lens molding trials. The second phase has dealt with the development of an improved lens design, a full size parquet lamination process, and a second group of injection molding lens molding trials.

Hodge, R.C.

1982-12-01

119

Partially coherent ambiguity functions for depth-variant point spread function design  

Digital Repository Infrastructure Vision for European Research (DRIVER)

The ambiguity function (AF) provides a convenient way to model how a camera with a modified aperture responds to defocus. We use the AF to design an optimal aperture distribution, which creates a depth-variant point spread function (PSF) from a sparse set of desired intensity patterns at different focal depths. Prior knowledge of the coherence state of the light is used to constrain the optimization in the mutual intensity domain. We use an assumption of spatially coherent light to design a f...

Horstmeyer, Roarke; Oh, Se Baek; Gupta, Otkrist; Raskar, Ramesh

2011-01-01

120

The Design Of Speech-Control Power Point Presentation Tool Using Arm7  

Directory of Open Access Journals (Sweden)

Full Text Available This paper was mainly exploring the important tool for many people who were exchanging knowledge especially proceeding power-point presentation as one auxiliary tool. The lecturer’s most proper position should be between the audience and screen of power-point and this location is far away the mouse or keyboard and also if he want go for particular slide using mouse or keyboard is long process, so if we have designed one facility with wireless control and could be controlled with speech-recognition function so that users need not rush between the screen and computer and also he can easily go for particular slide. Today some identical products with RF [1] and push function on the power-point pen that needs users to pre-learn the functions and those usage often caused errors especially in the dark environment, so in this paper we combined WSN ZigBee modules [2] with speech-recognition function and ARM7 based LPC2148 microcontroller to design the creative product, so to called “Hi-TEC ZigBee remotecontroller of Power-Point presentation”.

P.Vishnu Kumar, Dr.T.JayaChandra Prasad

2012-08-01

 
 
 
 
121

Design and development of a laminated Fresnel lens for point focus pv systems  

Energy Technology Data Exchange (ETDEWEB)

The design and fabrication of a laminated Fresnel lens for point focus photovoltaic concentrators systems is described. The lens consists of a glass superstrate to which a thin 6.7 inch square Fresnel lens is bonded. A key aim of the program was to investigate the technical feasibility of injection molding acceptable quality Fresnel lenses. Significant progress was made in demonstrating this feasibility and is reported.

Hobbs, R.B. Jr.

1981-01-01

122

Design and development of a laminated glass-plastic Fresnel lens for point focus photovoltaic systems  

Energy Technology Data Exchange (ETDEWEB)

The design and development of a laminated glass-plastic Fresnel lens for point focus photovoltaic systems use is described. The objective of this development was to examine the feasibility of producing lenses with a cost effectiveness superior to that of lenses made by casting of acrylic. The procedure used in executing this development, the method used in cost effectiveness evaluation, results obtained and recommendations for further work are presented.

Matalon, L. A.

1982-08-01

123

Design and Simulation of PV System with Incremental Conductance Method for Maximum Power Point Tracking  

Directory of Open Access Journals (Sweden)

Full Text Available This paper presents a complete design and simulation of a Photovoltaic System (PVS with capable of Maximum Power Point Tracking (MPPT.In this paper Incremental Conductance Method (ICM is adopted for the MPPT technique. The proposed PV System is modelled and simulated in MATLAB/Simulink GUI environment. Finally, dynamic performance of the proposed PV System with ICM is presented to demonstrate its capability of MPPT, which has a better tracking performance.

Uma Maheswara Rao Ch., Bala Murali Krishna V., A. Srihari Babu, Suman S.

2014-05-01

124

Eye Problems in Radiologists  

Directory of Open Access Journals (Sweden)

Full Text Available In recent years, technologic advances (including the"nintroduction of MDCT coupled with an increasing"nnumber of unfilled radiology positions have led to an"nincreasing workload for radiologists. In fact radiologists"nworking under a heavy workload potentially face"na range of health issues, including musculoskeletal"ninjuries, eye strain and other problems. Eye strain is"na well-recognized consequence of computer overuse"nand it may be a particular issue for radiologists."nPosterior subcapsular cataract (PSC is common"namong interventional radiologists. Visual acuity is"neasily measured and corrected, but very little has"nbeen written regarding its importance to practicing"nradiologists. Eye strain is common in radiologists and"nit does not vary significantly between those using"nPACS and film. Improving the ergonomic design"nof workstations and modifying the work habits of"ncomputer users (with supplementary breaks have"nbeen shown to have positive effects on eye strain"nin these workers. Interventional radiologists are at"nhigh risk of radiation-induced eye injury and should"nconsider eye protection to avoid posterior subcapsular"n(PSC cataract formation. There is a progressive"nnormal deterioration in visual acuity with age which"nwill affect all radiologists, and in addition, there may"nbe an increased effect from the non-stochastic effect of"nionising radiation on the lens. According to abundance"nof eye problems related to over-use of computers in"nradiologists recognition and proper prevention of"nthem is necessary for radiologists.

Morteza Tahmasebi

2011-05-01

125

Star Tracker Based ATP System Conceptual Design and Pointing Accuracy Estimation  

Science.gov (United States)

A star tracker based beaconless (a.k.a. non-cooperative beacon) acquisition, tracking and pointing concept for precisely pointing an optical communication beam is presented as an innovative approach to extend the range of high bandwidth (> 100 Mbps) deep space optical communication links throughout the solar system and to remove the need for a ground based high power laser as a beacon source. The basic approach for executing the ATP functions involves the use of stars as the reference sources from which the attitude knowledge is obtained and combined with high bandwidth gyroscopes for propagating the pointing knowledge to the beam pointing mechanism. Details of the conceptual design are presented including selection of an orthogonal telescope configuration and the introduction of an optical metering scheme to reduce misalignment error. Also, estimates are presented that demonstrate that aiming of the communications beam to the Earth based receive terminal can be achieved with a total system pointing accuracy of better than 850 nanoradians (3 sigma) from anywhere in the solar system.

Orfiz, Gerardo G.; Lee, Shinhak

2006-01-01

126

Highly effective and accurate weak point monitoring method for advanced design rule (1x nm) devices  

Science.gov (United States)

Historically when we used to manufacture semiconductor devices for 45 nm or above design rules, IC manufacturing yield was mainly determined by global random variations and therefore the chip manufacturers / manufacturing team were mainly responsible for yield improvement. With the introduction of sub-45 nm semiconductor technologies, yield started to be dominated by systematic variations, primarily centered on resolution problems, copper/low-k interconnects and CMP. These local systematic variations, which have become decisively greater than global random variations, are design-dependent [1, 2] and therefore designers now share the responsibility of increasing yield with manufacturers / manufacturing teams. A widening manufacturing gap has led to a dramatic increase in design rules that are either too restrictive or do not guarantee a litho/etch hotspot-free design. The semiconductor industry is currently limited to 193 nm scanners and no relief is expected from the equipment side to prevent / eliminate these systematic hotspots. Hence we have seen a lot of design houses coming up with innovative design products to check hotspots based on model based lithography checks to validate design manufacturability, which will also account for complex two-dimensional effects that stem from aggressive scaling of 193 nm lithography. Most of these hotspots (a.k.a., weak points) are especially seen on Back End of the Line (BEOL) process levels like Mx ADI, Mx Etch and Mx CMP. Inspecting some of these BEOL levels can be extremely challenging as there are lots of wafer noises or nuisances that can hinder an inspector's ability to detect and monitor the defects or weak points of interest. In this work we have attempted to accurately inspect the weak points using a novel broadband plasma optical inspection approach that enhances defect signal from patterns of interest (POI) and precisely suppresses surrounding wafer noises. This new approach is a paradigm shift in wafer inspection by leveraging systematic defect locations for high sensitivity inspection, thereby enhancing the discovery and monitoring of yield-limiting defects at traditional optical inspection throughput.

Ahn, Jeongho; Seong, ShiJin; Yoon, Minjung; Park, Il-Suk; Kim, HyungSeop; Ihm, Dongchul; Chin, Soobok; Sivaraman, Gangadharan; Li, Mingwei; Babulnath, Raghav; Lee, Chang Ho; Kurada, Satya; Brown, Christine; Galani, Rajiv; Kim, JaeHyun

2014-04-01

127

What Is Dry Eye?  

Medline Plus

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128

What Is Dry Eye?  

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Full Text Available ... approved information from EyeSmart Causes of Dry Eye - Eye M.D.-approved information from EyeSmart Related Answers Is surgery to remove pterygia and pingueculae safe? Can floaters ...

129

What Is Dry Eye?  

Medline Plus

Full Text Available ... Dry Eye Floaters & Flashes Glaucoma Hyperopia (Farsightedness) Low Vision Myopia (Nearsightedness) Pink Eye (Conjunctivitis) Presbyopia (Aging Eye) ... Symptoms Blurriness Dark Curtain Dark Spots Discharge Double Vision Drooping Eyelid Eye Pain Eyelash Crusting Eyelid Lump ...

130

Point Selection for Triangular 2-D Mesh Design Using Adaptive Forward Tracking Algorithm  

Directory of Open Access Journals (Sweden)

Full Text Available Two-dimensional mesh-based motion tracking preserves neighboring relations (through connectivity of the mesh and also allows warping transformations between pairs of frames; thus, it effectively eliminates blocking artifacts that are common in motion compensation by block matching. However, available uniform 2-D mesh model enforces connec-tivity everywhere within a frame, which is clearly not suitable across occlusion boundaries. To overcome this limitation, BTBC (background to be covered detection and MF (model failure detection algorithms are being used. In this algorithm, connectivity of the mesh elements (patches across covered and uncovered region boundaries are broken. This is achieved by allowing no node points within the background to be covered and refining the mesh structure within the model failure region at each frame. We modify the occlusion-adaptive, content-based mesh design and forward tracking algorithm used by Yucel Altunbasak for selection of points for triangular 2-D mesh design. Then, we propose a new triangulation procedure for mesh structure and also a new algorithm to justify connectivity of mesh structure after motion vector estimation of the mesh points. The modified content-based mesh is adaptive which eliminates the necessity of transmission of all node locations at each frame.

Nastaran Borjian

2011-02-01

131

Design and Implementation of Floating Point Multiplier for Better Timing Performance  

Directory of Open Access Journals (Sweden)

Full Text Available IEEE Standard 754 floating point is the most common representation today for real numbers on computers. This paper gives a brief overview of IEEE floating point and its representation. This paper describes a single precision floating point multiplier for better timing performance. The main object of this paper is to reduce the power consumption and to increase the speed of execution by implementing certain algorithm for multiplying two floating point numbers. In order to design this VHDL is the hardware description language is used and targeted on a Xilinx Spartan-3 FPGA. The implementation’s tradeoffs are area speed and accuracy. This multiplier also handles overflow and underflow cases. For high accuracy of the results normalization is also applied. By the use of pipelining process this multiplier is very good at speed and accuracy compared with the previous multipliers. This pipelined architecture is described in VHDL and is implemented on Xilinx Spartan 3 FPGA. Timing performance is measured with Xilinx Timing Analyzer. Timing performance is compared with standard multipliers.

B.Sreenivasa Ganesh,J.E.N.Abhilash, G. Rajesh Kumar

2012-09-01

132

Nonistropic point spread function as a result of collimator design and manufacturing defects.  

Science.gov (United States)

A point spread function (PSF) which was of an unusual form was observed when using a low energy collimator and a 99mTc point source. A lack of radial symmetry and the detection of events over 20 cm away from the center of the source were noted. The major quantitative effect of this was a variation in the resolution of the system with direction. The consequences of this are likely to be of importance especially for single photon emission computed tomographic (SPECT) imaging. The effect was produced by a combination of faults in the design and manufacture of the low energy collimators. It demonstrates the importance of making quantitative measurements of collimator performance in the quality control assessment of gamma camera systems. For SPECT imaging the replacement of lead foil collimators with cast collimators should be considered. PMID:3259626

Gillen, G J; Hilditch, T E; Elliott, A T

1988-06-01

133

Critical Points of Contact : Exploring networked relations in urban mobility and service design  

DEFF Research Database (Denmark)

In contemporary urban societies multiple networks and systems interact, overlap, exist in parallel, converge, conflict etc. creating unforeseen complexity and less transparency. By exploring how layered networks of physical movement, service information, goods delivery, commercial communication etc. are connected (and disconnected) we get a much better understanding of how to design and intervene regardless if we are thinking about public spaces in the city or new systems of service design. The many networks orchestrating and facilitating contemporary everyday life are dependent on the strategic sites where the networks meet and establish contact. Thus we argue for the usefulness of the notion of Critical Point of Contact (CPC) to deepen our understanding of the actual life within networks. En route to this notion we draw upon theories within as diverse realms such as interaction design, service design, geography, and mobility studies. After the introduction in section we develop and define the notion of CPC based upon a broad set of disciplines and theories. We illustrate the usefulness of the notion within the field of mobility in the network city and within the field of service design. The paper ends with concluding remarks and perspectives for further theoretical as well as empirical work in prolongation of this beginning research effort.

Jensen, Ole B.; Morelli, Nicola

2011-01-01

134

Design point variation of 3-D loss and deviation for axial compressor middle stages  

Science.gov (United States)

The available data on middle-stage research compressors operating near design point are used to derive simple empirical models for the spanwise variation of three-dimensional viscous loss coefficients for middle-stage axial compressor blading. The models make it possible to quickly estimate the total loss and deviation across the blade span when the three-dimensional distribution is superimposed on the two-dimensional variation calculated for each blade element. It is noted that extrapolated estimates should be used with caution since the correlations have been derived from a limited data base.

Roberts, William B.; Serovy, George K.; Sandercock, Donald M.

1988-01-01

135

Fixed-Point Design of Generalized Comb Filters: A Statistical Approach  

CERN Multimedia

This paper is concerned with the problem of designing computationally efficient Generalized Comb Filters (GCF). Basically, GCF filters are anti-aliasing filters that guarantee superior performance in terms of selectivity and quantization noise rejection compared to classical comb filters, when used as decimation filters in multistage architectures. Upon employing a partial polyphase (PP) architecture proposed in a companion paper, we develop a sensitivity analysis in order to investigate the effects of the coefficients' quantization on the frequency response of the designed filters. We show that the sensitivity of the filter response to errors in the coefficients is dependent on the particular split of the decimation factor between the two sub-filters constituting the PP architecture. The sensitivity analysis is then used for developing a fixed-point implementation of a sample filter from the class of GCF filters, used as reference filter throughout the paper. Finally, we present computer simulations in order...

Laddomada, Massimiliano

2008-01-01

136

Design and Evaluation of Large-Aperture Gallium Fixed-Point Blackbody  

Science.gov (United States)

To complement existing water bath blackbodies that now serve as NIST primary standard sources in the temperature range from 15 °C to 75 °C, a gallium fixed-point blackbody has been recently built. The main objectives of the project included creating an extended-area radiation source with a target emissivity of 0.9999 capable of operating either inside a cryo-vacuum chamber or in a standard laboratory environment. A minimum aperture diameter of 45 mm is necessary for the calibration of radiometers with a collimated input geometry or large spot size. This article describes the design and performance evaluation of the gallium fixed-point blackbody, including the calculation and measurements of directional effective emissivity, estimates of uncertainty due to the temperature drop across the interface between the pure metal and radiating surfaces, as well as the radiometrically obtained spatial uniformity of the radiance temperature and the melting plateau stability. Another important test is the measurement of the cavity reflectance, which was achieved by using total integrated scatter measurements at a laser wavelength of 10.6 ?m. The result allows one to predict the performance under the low-background conditions of a cryo-chamber. Finally, results of the spectral radiance comparison with the NIST water-bath blackbody are provided. The experimental results are in good agreement with predicted values and demonstrate the potential of our approach. It is anticipated that, after completion of the characterization, a similar source operating at the water triple point will be constructed.

Khromchenko, V. B.; Mekhontsev, S. N.; Hanssen, L. M.

2009-02-01

137

Constrained LQR Design Using Interior-Point Arc-Search Method for Convex Quadratic Programming with Box Constraints  

Digital Repository Infrastructure Vision for European Research (DRIVER)

Although the classical LQR design method has been very successful in real world engineering designs, in some cases, the classical design method needs modifications because of the saturation in actuators. This modified problem is sometimes called the constrained LQR design. For discrete systems, the constrained LQR design problem is equivalent to a convex quadratic programming problem with box constraints. We will show that the interior-point method is very efficient for this...

Yang, Yaguang

2013-01-01

138

Designing DOKK1 from a childâ??s point of view  

DEFF Research Database (Denmark)

Designing DOKK1 from a childâ??s point of view By Aviaja Borup Lynggaard & Birgitte Geert Jensen This poster presents a design case of collaborative innovation between design students from Aarhus School of Architecture and pupils from the public school, Samsøgades School in Aarhus, facilitated by the research project Kids nâ??Tweens Lifestyle. The scope of collaborating was to design the content for DOKK1, the new Mediaspace center in Aarhus, where design students took offset from the childrenâ??s world in a creative workshop as inspiration for the final design proposals. The task was carried out in collaboration with the working group on the new Dokk1 and the goal was to create a library that makes sense for the whole family. Some of the questions that the students wanted to answer was: â?¢ How can you create a library where there are joint activities that makes sense for the whole family? â?¢ How to create fun for families in the library? â?¢ How can play help to promote interaction and communication? The students worked with the space in Dokk1 as the â??third placeâ?, which is identified by Oldenburg (1999) as â??great good placesâ?, being public places on neutral ground where people can gather and interact. The cooperative design workshop led to a range of insights and inspiration for the students to implement in their design solutions. An issue that the workshop revealed concerned a variety of interests and requirements when designing across ages. The age difference between users calls for variations in the use of space and design. The workshop also showed that the â??third placeâ? is achieved today in existing places around the city, such as in shops and banks. Therefore, several of the solutions showed that there is need to create a residence that can accommodate the versatility and give space for user participation. The workshop was facilitated by Kids nâ??Tweens Lifestyle, as part of method development when engaging children in the design process. 8 groups were formed and a range of creative methods was tested. The methods varied from: Model making, lego prototyping, mood boards/blocks, inspirational pictures, future scenarios (library in 500 years), thinking out loud, body storming and sketching. The outcome led to new insights about the end users and an ideacatalogue for the students to elaborate from. The poster will present two design results â?? â??Bookscapeâ? and â??Tumbleâ?. Bookscape took offset from the childrenâ??s aspiration to create small and private spaces, as the shelves can be moved and thus act as space makers. The storage of the books provides a platform where new activities can take place. Tumble took offset from the pupilsâ?? request towards being able to perform multiple activities in DOKK1. This led to the design of transformative furniture that can be rolled around on 4 different edges that each enables different activities. We presented an innovative collaboration between design students and pupils from a public school. A creative workshop led to manifold projects, where two are presented in this poster to exemplify how the inputs from children can feed a creative design process.

Geert Jensen, Birgitte; Borup Lynggaard, Aviaja

139

Experimental Investigation of a Point Design Optimized Arrow Wing HSCT Configuration  

Science.gov (United States)

The M2.4-7A Arrow Wing HSCT configuration was optimized for straight and level cruise at a Mach number of 2.4 and a lift coefficient of 0.10. A quasi-Newton optimization scheme maximized the lift-to-drag ratio (by minimizing drag-to-lift) using Euler solutions from FL067 to estimate the lift and drag forces. A 1.675% wind-tunnel model of the Opt5 HSCT configuration was built to validate the design methodology. Experimental data gathered at the NASA Langley Unitary Plan Wind Tunnel (UPWT) section #2 facility verified CFL3D Euler and Navier-Stokes predictions of the Opt5 performance at the design point. In turn, CFL3D confirmed the improvement in the lift-to-drag ratio obtained during the optimization, thus validating the design procedure. A data base at off-design conditions was obtained during three wind-tunnel tests. The entry into NASA Langley UPWT section #2 obtained data at a free stream Mach number, M(sub infinity), of 2.55 as well as the design Mach number, M(sub infinity)=2.4. Data from a Mach number range of 1.8 to 2.4 was taken at UPWT section #1. Transonic and low supersonic Mach numbers, M(sub infinity)=0.6 to 1.2, was gathered at the NASA Langley 16 ft. Transonic Wind Tunnel (TWT). In addition to good agreement between CFD and experimental data, highlights from the wind-tunnel tests include a trip dot study suggesting a linear relationship between trip dot drag and Mach number, an aeroelastic study that measured the outboard wing deflection and twist, and a flap scheduling study that identifies the possibility of only one leading-edge and trailing-edge flap setting for transonic cruise and another for low supersonic acceleration.

Narducci, Robert P.; Sundaram, P.; Agrawal, Shreekant; Cheung, S.; Arslan, A. E.; Martin, G. L.

1999-01-01

140

Mixed-flow vertical tubular hydraulic turbine. Determination of proper design duty point  

Energy Technology Data Exchange (ETDEWEB)

A new vertical single-regulated mixed-flow turbine with conical guide apparatus and without spiral casing is presented in this paper. Runner blades are fixed to the hub and runner band and resemble to the Francis type runner of extremely high specific speed. Due to lack of information and guidelines for the design of a new turbine, a theoretical model was developed in order to determinate the design duty point, i.e. to determine the optimum narrow operation range of the turbine. It is not necessary to know the kinematic conditions at the runner inlet, but only general information on the geometry of turbine flow-passage, meridional contour of the runner and blading, the number of blades and the turbine speed of rotation. The model is based on the integral tangential lift coefficient, which is the average value over the entire runner blading. The results are calculated for the lift coefficient 0.5 and 0.6, for the flow coefficient range from 0.2 to 0.36, for the number of the blades between 5 and 13, and are finally presented in the Cordier diagram (specific speed vs. specific diameter). Calculated results of the turbine optimum operation in Cordier diagram correspond very well to the adequate area of Kaplan turbines with medium and low specific speed and extends into the area of Francis turbines with high specific speed. Presented model clearly highlights the parameters that affect specific load of the runner blade row and therefore the optimum turbine operation (discharge - turbine head). The presented method is not limited to a specific reaction type of the hydraulic turbine. The method can therefore be applied to a wide range from mixed-flow (radial-axial) turbines to the axial turbines. Applicability of the method may be considered as a tool in the first stage of the turbine design i.e. when designing the meridional geometry and selecting the number of blades according to calculated operating point. Geometric and energy parameters are generally defined to an extent that these parameters are considered in detailed design using turbulent viscous flow CFD solver. (orig.)

Sirok, B. [Ljubljana Univ. (Slovenia). Faculty of Mechanical Engineering; Bergant, A. [Litostroj Power, d.o.o., Ljubljana (Slovenia); Hoefler, E.

2011-12-15

 
 
 
 
141

Simulation of eye-safe imaging laser radar for advanced range estimation and improved design process using VRML  

Science.gov (United States)

Eye-safe laser radar systems based on gated viewing use narrow infrared laser pulses to illuminate a whole scene for direct (incoherent) detection. Due to the time of flight principle and a very fast shutter with precisely controlled delay time, only light reflected in a certain range slice is detected. Due to the lack of off-shelf components, the development of such systems is difficult. Also, comparison of different systems is complicated, since atmospheric transmission, target reflectivity, polarization, and different noise effects have great influence on the system performance. The laser radar equation is used to estimate range performance in a a general manner. In this paper we discuss improvements in the system modelling of our laser radar system. Pixel wise simulation in combination with three dimensional scenes, generated with Virtual Reality Markup Language (VRML) is used to generate realistic range images. Changing to a pixel oriented approach and three dimensional modelled scenes, we are now able to study the system response for targets with arbitrary form and even different reflectivity. Also, we take into account the gaussian nature of the illuminating laser spot and different noise sources. Hence it is possible to simulate gray value images and calculate range images.

Schael, Ulrich; Rothe, Hendrik

2003-10-01

142

Performance comparison of liquid metal and gas cooled ATW system point designs  

International Nuclear Information System (INIS)

As part of the Advanced Accelerator Application (AAA) program in the U.S., preliminary design studies have been performed at Argonne National Laboratory (ANL) and Los Alamos National Laboratory (LANL) to define and compare candidate Accelerator Transmutation of Waste (ATW) systems. The studies at ANL have focused primarily on the transmutation blanket component of the overall system. Lead-bismuth eutectic (LBE), sodium, and gas cooled systems are among the blanket technology options currently under consideration. This paper summarizes the results from neutronics trade studies performed at ANL. Core designs have been developed for LBE and sodium cooled 840 MWt fast spectrum accelerator driven systems employing re-cycle. Additionally, neutronics analyses have been performed for a helium-cooled 600 MWt hybrid thermal and fast spectrum system proposed by General Atomics (GA), which is operated in the critical mode for three cycles and in a subcritical accelerator driven mode for a subsequent single cycle. For these three point designs, isotopic inventories, consumption rates, and annual burnup rates are compared. The mass flows and the ultimate loss of transuranic (TRU) isotopes to the waste stream per unit of heat generated during transmutation are also compared on a consistent basis. (author)

2001-04-08

143

Design of Neutral-Point Voltage Controller of a Three-level NPC Inverter with Small DC-Link Capacitors  

DEFF Research Database (Denmark)

A Neutral-Point-Clamped (NPC) three-level inverter with small dc-link capacitors is presented in this paper. The inverter requires zero average neutral-point current for stable neutral-point voltage. The small dc-link capacitors may not maintain capacitor voltage balance, even with zero neutral-point current. This may happen due to nonlinearities present in the circuit. This requires a fast control of the neutral-point voltage. A simple carrier based modulation strategy which allows modeling of the neutral-point voltage dynamics as a continuous function of power drawn from the inverter is proposed. This continuous model shows that the neutral-point current is proportional to the power drawn from the inverter, and it enables the use of well established classical control theory for the neutral-point voltage controller design. A simple PI (proportional integral) controller is designed for the neutral-point voltage control on the basis of the continuous model. The design method for optimum performance is discussed. The implementation of the proposed modulation strategy and the controller is very simple. The controller is implemented in a 7.5 kW induction machine based drive with only 14 ìF dc-link capacitors. Also, the experimental results show that fast and stable performance of the neutral-point voltage controller are achieved and thus verify the validity of the proposed control approach.

Maheshwari, Ram Krishan; Munk-Nielsen, Stig

2013-01-01

144

Acupuncture for dry eye: a randomised controlled trial protocol  

Directory of Open Access Journals (Sweden)

Full Text Available Abstract Background Dry eye is usually managed by conventional medical interventions such as artificial tears, anti-inflammatory drugs and surgical treatment. However, since dry eye is one of the most frequent ophthalmologic disorders, safer and more effective methods for its treatment are necessary, especially for vulnerable patients. Acupuncture has been widely used to treat patients with dry eye. Our aim is to evaluate the effectiveness and safety of acupuncture for this condition. Methods/Design A randomised, patient-assessor blinded, sham (non-acupuncture point, shallow acupuncture controlled study was established. Participants allocated to verum acupuncture and sham acupuncture groups will be treated three times weekly for three weeks for a total of nine sessions per participant. Seventeen points (GV23; bilateral BL2, GB4, TE23, Ex1 (Taiyang, ST1 and GB20; and left SP3, LU9, LU10 and HT8 for men, right for women have been selected for the verum acupuncture; for the sham acupuncture, points have been selected that do not coincide with a classical acupuncture point and that are located close to the verum points, except in the case of the rim of the eye. Ocular surface disease index, tear film breakup time, the Schirmer I test, medication quantification scale and general assessment of improvement will be used as outcome variables for evaluating the effectiveness of acupuncture. Safety will also be assessed at every visit. Primary and secondary outcomes will be assessed four weeks after screening. All statistical analyses will be performed using analysis of covariance. Discussion The results of this trial will be used as a basis for clarifying the efficacy of acupuncture for dry eye. Trial registration ClinicalTrials.gov NCT00969280.

Kim Ae-Ran

2009-12-01

145

Design and Development of Intracavity Optical Parametric Oscillator-based Eye Safe Laser Operating at 20 Hz without Forced Air Cooling  

Directory of Open Access Journals (Sweden)

Full Text Available In this paper we report\tthe design and development of an electro-optically\tQ-switched diode\tpumped\tNd:YAG\tlaser with intracavity optical parametric oscillator, generating ~ 5 ns laser pulses of ~8 mJ energy at eye safe wavelength of 1534 nm. A\tZ-shaped laser resonator has\tbeen designed with porro prism\tend\treflector in Q-switch arm containing\tRTP\tQ-Switch\tand\ta suitably oriented waveplate. The gain arm consists of a Ø3\tx 72\tmm\tNd:\tYAG laser\trod,\tpumped\tfrom\tone\tside\tby 3\tx 5 bar laser diode array stack\temitting\ttotal\toptical peak\tpower of\t740\tW at 804 nm at 38 °C. Thermoelectric coolers (TECs have been employed to maintain the optimum temperature of laser diode arrays and the combined heat load from the pump chamber and TECs is distributed over the system base plate with embedded\theat\tpipes. Such cooling mechanism\thas\teliminated the requirement\tof fins and fans in\tthe laser\tsystem.\tEye\tsafe\tradiation\tis out-coupled through\tintra\tcavity KTA OPO\t(5 x\t5\tx 20\tmm3 placed in the gain arm. Laser was operated at 20 Hz for several duty cycles of 10 min on and 10 min off and output energy remained\tstable\twithin\t±0.5\tmJ\twithout\tany\tforced\tair/liquid\tcooling.

Atul\tBhardwaj

2013-11-01

146

What Is Dry Eye?  

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Full Text Available Español Media Inquiries find an eye M.D. ask an eye M.D. Search GetEyeSmart.org Diseases & ... to blindness? Featured Video Norm Abram on Eye Safety 0:31 Subscribe for Eye Health Info Sign ...

147

LASIK - Laser Eye Surgery  

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Full Text Available Eye Health Lifestyle Topics Preventing Eye Injuries Healthy Eyes During Pregnancy Computer Usage & Eye Strain Maintaining Your Sight with ... Video LASIK (Femtosecond) 0:50 Subscribe for Eye Health Info Sign up for our monthly e-mail ...

148

Design of multi-point automatic positioning pre-programmed crane control system  

International Nuclear Information System (INIS)

This automatic positioning system is designed for the crane which is in common use. The crane hall is cut into several parts, the position is detected by the photoelectric switches, and the PLC and inverter are used for the control devices. The automatic positioning control of the crane is completed by means of the timing movement. The positioning error is less than 2.1 cm, the swing range when lifting object is less than 5.7 cm, and the average speed of the crane is more than 90% of the rated speed. This paper gives further description in the positioning control, direction control, speed control and the identification of the starting point. Finally it gives an analysis of the automatic positioning performance. (authors)

2010-02-01

149

Charge density distributions derived from smoothed electrostatic potential functions: design of protein reduced point charge models.  

Science.gov (United States)

To generate reduced point charge models of proteins, we developed an original approach to hierarchically locate extrema in charge density distribution functions built from the Poisson equation applied to smoothed molecular electrostatic potential (MEP) functions. A charge fitting program was used to assign charge values to the so-obtained reduced representations. In continuation to a previous work, the Amber99 force field was selected. To easily generate reduced point charge models for protein structures, a library of amino acid templates was designed. Applications to four small peptides, a set of 53 protein structures, and four KcsA ion channel models, are presented. Electrostatic potential and solvation free energy values generated by the reduced models are compared with the corresponding values obtained using the original set of atomic charges. Results are in closer agreement with the original all-atom electrostatic properties than those obtained with a previous reduced model that was directly built from the smoothed MEP functions [Leherte and Vercauteren in J Chem Theory Comput 5:3279-3298, 2009]. PMID:21915750

Leherte, Laurence; Vercauteren, Daniel P

2011-10-01

150

From Takeoff to Landing: Looking at the Design Process for the Development of NASA Blast at Thanksgiving Point  

Directory of Open Access Journals (Sweden)

Full Text Available In this article we discuss the process of design used to develop and design the NASA Blast exhibition at Thanksgiving Point, a museum complex in Lehi, Utah. This was a class project for the Advanced Instructional Design Class at Brigham Young University. In an attempt to create a new discourse (Krippendorff, 2006 for Thanksgiving Point visitors and staff members, the design class used a very fluid design approach by utilizing brainstorming, researching, class member personas, and prototyping to create ideas for the new exhibition. Because of the nature of the experience, the design class developed their own techniques to enhance the process of their design. The result of the design was a compelling narrative that brought all the elements of the exhibition together in a cohesive piece.

Stephen Ashton

2011-01-01

151

Computational design and biophysical characterization of aggregation-resistant point mutations for ?D crystallin illustrate a balance of conformational stability and intrinsic aggregation propensity.  

Science.gov (United States)

?D crystallin is a natively monomeric eye-lens protein that is associated with hereditary juvenile cataract formation. It is an attractive model system as a multidomain Greek-key protein that aggregates through partially folded intermediates. Point mutations M69Q and S130P were used to test (1) whether the protein-design algorithm RosettaDesign would successfully predict mutants that are resistant to aggregation when combined with informatic sequence-based predictors of peptide aggregation propensity and (2) how the mutations affected relative unfolding free energies (??G(un)) and intrinsic aggregation propensity (IAP). M69Q was predicted to have ??G(un) ? 0, without significantly affecting IAP. S130P was predicted to have ??G(un) ? 0 but with reduced IAP. The stability, conformation, and aggregation kinetics in acidic solution were experimentally characterized and compared for the variants and wild-type (WT) protein using circular dichroism and intrinsic fluorescence spectroscopy, calorimetric and chemical unfolding, thioflavin-T binding, chromatography, static laser light scattering, and kinetic modeling. Monomer secondary and tertiary structures of both variants were indistinguishable from WT, while ??G(un) > 0 for M69Q and ??G(un) < 0 for S130P. Surprisingly, despite being the least conformationally stable, S130P was the most resistant to aggregation, indicating a significant decrease of its IAP compared to WT and M69Q. PMID:21184609

Sahin, Erinc; Jordan, Jacob L; Spatara, Michelle L; Naranjo, Andrea; Costanzo, Joseph A; Weiss, William F; Robinson, Anne Skaja; Fernandez, Erik J; Roberts, Christopher J

2011-02-01

152

Prostaglandins and the eye.  

Science.gov (United States)

Prostaglandins are present in the iris and cilliary body and are synthesized in these tissues. Prostaglandins are released into the aqueous following a variety of insults to the eye, and the results of such trauma can be reproduced by the application of prostaglandins to the eye. Prostaglandins have been detected in the aqueous of patients suffering from endogenous uveitis and it is probable that the anti-inflammatory effects of drugs such as aspirin and indomethacin are due to their prostaglandin antagonistic actions. little is known yet concerning the physiological role of prostaglandins in the eye, but their association with adrenergic mechanisms, which is now being studied, may produce some clarification. The relationship between prostaglandins and antidromic stimulation of sensory nerves and the so-called axon reflex is still obscure and it would be ironic if the miosis following stimulation of the Vth nerve, which was the starting-point for the discovery of irin and its subsequent identification with prostaglandins, is not in fact due to prostaglandin but to some other chemical mediator. PMID:1130238

Perkins, E S

1975-01-01

153

What Is Dry Eye?  

Medline Plus

Full Text Available ... By producing tears at a slow and steady rate, the eye stays moist and comfortable. The eye ... It can make tears at a slow, steady rate to maintain normal eye lubrication. It can also ...

154

Diabetic Eye Problems  

Science.gov (United States)

... is a cloud over the lens of your eye. Surgery helps you see clearly again. Glaucoma happens when ... up in the eye, damaging the main nerve. Eye drops or surgery can help. If you have diabetes, you should ...

155

Dry eye syndrome  

Science.gov (United States)

... be caused by: Heat or chemical burns Previous eye surgery A rare autoimmune disorder in which the glands ... eye symptoms are due to sleeping with the eyes slightly open. ... sleep. Surgery may be helpful if symptoms are because the ...

156

Diabetes - Eye Complications  

Medline Plus

Full Text Available ... further bleeding. When bleeding in the vitreous occurs, eye surgery to remove the vitreous is also available. Other Eye Problems Diabetic patients can have other eye problems ...

157

Eye muscle repair  

Science.gov (United States)

... The condition is more commonly known as "crossed eyes." Surgery may be recommended when strabismus does not improve ... Eye muscle surgery does not fix the poor vision of a lazy (amblyopic) eye. The child may have to ...

158

A stochastic point rainfall model of design storms based on 2-copula and dimensionless hyetograph  

Science.gov (United States)

In this study a stochastic model to derive synthetic design storms at a point is presented. Generated rainfall events are totally stochastic but with characteristics in terms of shape, duration and average intensity have to satisfy the parameters derived by statistical analyses of the available historic records. The main advantage of this kind of approach is its applicability when few years of sub-hourly rainfall records, not necessary continuous, are available. The events are derived on the basis of a fixed inter-event time, and selected if their average intensity is bigger than a critical fixed one. In order to characterize the shape, dimensionless events are considered. The probability function to describe the hyetograph shape chosen in this study is the Beta cumulative distribution. Storm duration and average intensity of the observed events are modelled separately by fitting several probability distribution and selecting the best one using several statistical criteria. Finally, their correlation is modelled using the Frank Copula. In order to test the methodology, two sites placed in Sicily, Italy, were sub-hourly rainfall data were available, have been analyzed. The considered raingauges stations are: Monreale, placed in North-West part of Sicily, and Palazzolo Acreide, placed in South-East part of Sicily, where 10 minutes recorded rainfall data were available. The good performance of the model has been tested by comparing the statistics of the simulated events with those of the measured data, and the obtained results confirm the effectiveness of the methodology.

Brigandì, Giuseppina; Tito Aronica, Giuseppe

2013-04-01

159

Comparison of the most common HRV computation algorithms from the systems designer point of view.  

Science.gov (United States)

In this paper we examine the most commonly used algorithms for the computation of heart rate variability as well as some other interesting approaches. The aim of the paper is to study the problem from a different point of view, that of the systems designer. The selected algorithms are compared to each other through experimental analysis and theoretical study. The comparison criteria are efficiency, complexity, size of the object code, memory requirements, power consumption, parallel complexity and speedup achieved, ability to response in real time, simplicity of the interface and implementation in hardware. The motivation is strong since heart rate variability is an interesting problem which finds application not only in conventional computing systems, but also in small, even wearable devices implemented using embedded systems technology or directly in hardware. The computation of heart rate variability for a set of signal recordings and the classification achieved for these signals with each examined method are also presented. Signals have been recorded from young and elderly subjects and the examined methods are used to classify them into these two distinct groups. PMID:19205990

Manis, G

2009-01-01

160

NGNP Point Design - Results of the Initial Neutronics and Thermal-Hydraulic Assessments During FY-03, Rev. 1  

Energy Technology Data Exchange (ETDEWEB)

This report presents the preliminary preconceptual designs for two possible versions of the Next Generation Nuclear Plant (NGNP), one for a prismatic fuel type helium gas-cooled reactor and one for a pebble bed fuel helium gas reactor. Both designs are to meet three basic requirements: a coolant outlet temperature of 1000 °C, passive safety, and a total power output consistent with that expected for commercial high-temperature gas-cooled reactors. The two efforts are discussed separately below. The analytical results presented in this report are very promising, however, we wish to caution the reader that future, more detailed, design work will be needed to provide final answers to a number of key questions including the allowable power level, the inlet temperature, the power density, the optimum fuel form, and others. The point design work presented in this report provides a starting point for other evaluations, and directions for the detailed design, but not final answers.

Philip E. MacDonald; James W. Sterbentz; Robert L. Sant; P. Bayless; H. D. Gougar; R. L. Moore; A. M. Ougouag; W. K. Terry

2003-09-01

 
 
 
 
161

Design of Multi-point Wireless Temperature and Humidity Sensor Network Based on NRF24l01  

Directory of Open Access Journals (Sweden)

Full Text Available Many fields need to use the multi-point data acquisition and transmission system to overcome the weakness of wired data transmission system. Based on the single chip transceiver nRF24L01 and favorite microprocessor STM32F107, designed the multi-point wireless sensor network. The system used the 1-wire temperature and humidity sensor DHT22 as Data acquisition components. The paper studied the hardware construction and the software design in details. Designed the circuit diagram, made the PCB plate, programmed software by Keil C and debugged with Keil uVision4 MDK V4.10. Results show that, the multi-point wireless sensor network can work more efficiently and more flexibility. It meets the performance requirements of high real-time, low power consumption and low cost.

Jin Gang

2013-01-01

162

Design of a Floating-Point Fused Add-Subtract Unit Using Verilog  

Directory of Open Access Journals (Sweden)

Full Text Available A floating-point (FP fused add-subtract unit is presented that performs simultaneous floating-point operation of add-subtract on a common pair of single-precision data at the same time that it takes to perform in a single addition with a conventional floating-point adder. The system was placed and routed in 45nm process so that there will be less consumption of memory as well as power.

Mayank Sharma,

2013-06-01

163

Design and Implementation of Numerical Linear Algebra Algorithms on Fixed Point DSPs  

Digital Repository Infrastructure Vision for European Research (DRIVER)

Numerical linear algebra algorithms use the inherent elegance of matrix formulations and are usually implemented using C/C++ floating point representation. The system implementation is faced with practical constraints because these algorithms usually need to run in real time on fixed point digital signal processors (DSPs) to reduce total hardware costs. Converting the simulation model to fixed point arithmetic and then porting it to a target DSP device is a difficult and time-consuming proce...

Zoran Nikoli?; Ha Thai Nguyen; Gene Frantz

2007-01-01

164

Imaging techniques for non invasive analysis of eye blinking dynamics  

Digital Repository Infrastructure Vision for European Research (DRIVER)

Our proposal consists of using of a fast camera attached to a slit lamp to record eye blinking. The corneal border and eye-lid are automatically detected. The images are ordered in a temporal stack which can be re-sliced thus allowing direct inspection of the variation of any point of the anterior's eye segment.

Mas Candela, David; Dome?nech Amigot, Begon?a; Espinosa Toma?s, Julia?n; Pe?rez Rodri?guez, Jorge; Herna?ndez Poveda, Consuelo; Illueca Contri, Carlos

2010-01-01

165

Hand-Eye Calibration Using Active Vision  

Science.gov (United States)

The project described in this paper designed and implemented a hand-eye calibration method for manipulators under observation by stereo cameras. This method has been utilized on Johnson Space Center's Robonaut, and on a planetary manipulator mock-up at the Jet Propulsion Laboratory. The intent of this calibration is to improve the manipulator's hand-eye coordination.

Nickels, Kevin; Huber, Eric; DiCicco, Matthew

2007-01-01

166

The use of a new design irrigator for the emergency treatment of chemical eye injuries in an accident and emergency department.  

Digital Repository Infrastructure Vision for European Research (DRIVER)

The introduction of a hand-held drench hose into a district general hospital accident and emergency department, for the emergency irrigation of chemically injured eyes is reported. The hose is described, together with the technique of irrigation. The advantages that a high-flow, low pressure system affords over conventional irrigation methods are discussed. The system appears to offer a simple, immediately available, effective tool for emergency eye care, which is suitable for use by a variet...

Watts, M. T.; Mulira, A.

1989-01-01

167

Sensitivity of Design Optimality Criteria to Second-order Response SurfaceModel Restrictions and Center Point Replications  

Directory of Open Access Journals (Sweden)

Full Text Available

Abstract In this work, we investigate the role of several model characteristics and center point replications on the properties of A-, D-, G-, and IV- optimality for four –factor second-order response surface design. It was discovered that A-, D-, and G- efficiencies tend to reduce as the center points are replicated while the effect on scaled average prediction variance tends to be very insignificant. Among the restricted models considered, the pure linear model (model1 turns out to be the best in terms of quality of estimation and model prediction.

Key words: Design optimality criteria; Center point replications; Response surface methodology

Angela U. Chukwu

2012-02-01

168

Design and Implementation of a Digital Controller for a Vibration Isolation and Vernier Pointing System  

Science.gov (United States)

This paper discusses the recommissioning of the Annular Suspension and Pointing System (ASPS), originally developed in the mid 1970's for pointing and vibration isolation of space experiments. The hardware was developed for NASA Langley Research Center by Sperry Flight Systems (now Honeywell Satellite Systems), was delivered to NASA in 1983. Recently, the hardware was loaned to Old Dominion University (ODU). The ASPS includes coarse gimbal assemblies and a Vernier Pointing Assembly (VPA) that utilize magnetic suspension to provide noncontacting vibration isolation and vernier pointing of the payload. The VPA is the main focus of this research. At ODU, the system has been modified such that it can now be operated in a l-g environment without a gravity offload. Suspension of the annular iron rotor in five degrees-of-freedom has been achieved with the use of modern switching power amplifiers and a digital controller implemented on a 486-class PC.

Neff, Daniel J.; Britcher, Colin P.

1996-01-01

169

Point- To- Point Protocol  

Directory of Open Access Journals (Sweden)

Full Text Available The telephone line provides a physical link, but to control and manage the transfer of data, there is a need for point-to-point connection. The first protocol devised for this purpose was serial line internet protocol (SLIP. However, SLIP has some deficiencies: it does not support protocols other than internet protocol (IP. It does not allow the IP addresses to be assigned dynamically, and it does not support authentication of the user. The POINT-TO-POINT (PPP is a protocol designed to respond to respond to the deficiencies. Today the PPP protocol standard finds wide use in asynchronous and synchronous connections between computers, bridges, routers and other intermediate devices.PPP is gaining acceptance as a standard for Integrated Services Digital Network(ISDN, and many implementations of X.25 also support PPP connection.

Immadisetty L V Chandrika,

2012-11-01

170

Space tug point design study. Volume 3: Design definition. Part 1: Propulsion and mechanical, avionics, thermal control and electrical power subsystems  

Science.gov (United States)

A study was conducted to determine the configuration and performance of a space tug. Details of the space tug systems are presented to include: (1) propulsion systems, (2) avionics, (3) thermal control, and (4) electric power subsystems. The data generated include engineering drawings, schematics, subsystem operation, and component description. Various options investigated and the rational for the point design selection are analyzed.

1973-01-01

171

MCNP-REN - A Monte Carlo Tool for Neutron Detector Design Without Using the Point Model  

Energy Technology Data Exchange (ETDEWEB)

The development of neutron detectors makes extensive use of the predictions of detector response through the use of Monte Carlo techniques in conjunction with the point reactor model. Unfortunately, the point reactor model fails to accurately predict detector response in common applications. For this reason, the general Monte Carlo N-Particle code (MCNP) was modified to simulate the pulse streams that would be generated by a neutron detector and normally analyzed by a shift register. This modified code, MCNP - Random Exponentially Distributed Neutron Source (MCNP-REN), along with the Time Analysis Program (TAP) predict neutron detector response without using the point reactor model, making it unnecessary for the user to decide whether or not the assumptions of the point model are met for their application. MCNP-REN is capable of simulating standard neutron coincidence counting as well as neutron multiplicity counting. Measurements of MOX fresh fuel made using the Underwater Coincidence Counter (UWCC) as well as measurements of HEU reactor fuel using the active neutron Research Reactor Fuel Counter (RRFC) are compared with calculations. The method used in MCNP-REN is demonstrated to be fundamentally sound and shown to eliminate the need to use the point model for detector performance predictions.

Abhold, M.E.; Baker, M.C.

1999-07-25

172

Diabetes - Eye Complications  

Medline Plus

Full Text Available ... eye problems such as blurred vision, cataract, and glaucoma. People with diabetes may have blurry vision when ... vision. Cataract can be fixed by minor surgery. Glaucoma is another disease of the eye that is ...

173

LASIK - Laser Eye Surgery  

Medline Plus

Full Text Available ... Computer Usage & Eye Strain Maintaining Your Sight with Diabetes Sports and Eye Protection Eyesight Risks for Smokers ... you have LASIK. If these materials raise any questions for you, be sure to discuss these questions ...

174

LASIK - Laser Eye Surgery  

Medline Plus

Full Text Available ... contacts, even with "no rub" solutions. Eye Protection at Home Every household should have at least one ... for your condition or treatment. Are You Fit at 40? A baseline eye exam is recommended at ...

175

What Is Dry Eye?  

Medline Plus

Full Text Available ... tears. By producing tears at a slow and steady rate, the eye stays moist and comfortable. The ... tears. It can make tears at a slow, steady rate to maintain normal eye lubrication. It can ...

176

LASIK - Laser Eye Surgery  

Medline Plus

Full Text Available ... eye care provider for your condition or treatment. Are You Fit at 40? A baseline eye exam ... where it heals in place. For people who are nearsighted, LASIK is used to flatten a cornea ...

177

Diabetes - Eye Complications  

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Full Text Available ... more likely to have eye problems that can lead to blindness. Many of these eye diseases can ... the retina can also get completely clogged and lead to the death of parts of the retina. ...

178

LASIK - Laser Eye Surgery  

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Full Text Available ... Page: Alternative Refractive Surgery Procedures Find An Eye M.D. Enter zip code here Search by Name, City, State or Subspecialty > Ask An Eye M.D. Enter your question here... Browse Top Answers > ...

179

Diagnostics of dry eye  

Directory of Open Access Journals (Sweden)

Full Text Available Introduction. Dry eye is a multi-factorial disease of tears and ocular surface resulting in symptoms of discomforts, vision disabilities, unstable tear film and possible damage to the ocular surface. The final diagnosis of dry eye results from collecting various data obtained in the course of several diagnostic procedures. Dry eye - diagnostic methods. Diagnosis of dry eye involves performing a series of clinical methods and laboratory tests. This paper presents some of the procedures used in the diagnosis of dry eye. Biomicroscopy of the eye with objective tests to check the tear film (Schirmer I, rose bengal, time break up precorneal tear film, verification of corneal sensitivity and impression cytology of the conjunctiva, are the optimum dry eye diagnostic routine procedures. Conclusion. The combination of clinical and histopathological methods of examination of the anterior ocular surface is the basis for a quality and precise diagnosis of dry eye.

Stankovi?-Babi? Gordana

2011-01-01

180

Healthy Eyes, Healthy Body  

Science.gov (United States)

... bodies and especially eyes. But what are they? • Lutein and Zeaxanthin: are carotenoids? that is, natural coloring ... vitamin A in the small intestine. Carotenoids like lutein and zeaxathin are naturally found in our eyes ...

 
 
 
 
181

Eye Cosmetic Safety  

Science.gov (United States)

... Vaccines, Blood & Biologics Animal & Veterinary Cosmetics Tobacco Products Cosmetics Print this page Share this page E-mail ... Contact Lenses Import Alerts Related to Cosmetics Eye Cosmetic Safety Most eye cosmetics are safe when used ...

182

New pediatric vision screener employing polarization-modulated, retinal-birefringence-scanning-based strabismus detection and bull's eye focus detection with an improved target system: opto-mechanical design and operation.  

Science.gov (United States)

ABSTRACT. Amblyopia ("lazy eye") is a major public health problem, caused by misalignment of the eyes (strabismus) or defocus. If detected early in childhood, there is an excellent response to therapy, yet most children are detected too late to be treated effectively. Commercially available vision screening devices that test for amblyopia's primary causes can detect strabismus only indirectly and inaccurately via assessment of the positions of external light reflections from the cornea, but they cannot detect the anatomical feature of the eyes where fixation actually occurs (the fovea). Our laboratory has been developing technology to detect true foveal fixation, by exploiting the birefringence of the uniquely arranged Henle fibers delineating the fovea using retinal birefringence scanning (RBS), and we recently described a polarization-modulated approach to RBS that enables entirely direct and reliable detection of true foveal fixation, with greatly enhanced signal-to-noise ratio and essentially independent of corneal birefringence (a confounding variable with all polarization-sensitive ophthalmic technology). Here, we describe the design and operation of a new pediatric vision screener that employs polarization-modulated, RBS-based strabismus detection and bull's eye focus detection with an improved target system, and demonstrate the feasibility of this new approach. PMID:24911020

Irsch, Kristina; Gramatikov, Boris I; Wu, Yi-Kai; Guyton, David L

2014-06-01

183

The ARIES-III D-3He tokamak reactor: Design-point determination and parametric studies  

International Nuclear Information System (INIS)

The multi-institutional ARIES study has generated a conceptual design of another tokamak fusion reactor in a series that varies the assumed advances in technology and physics. The ARIES-3 design uses a D-3He fuel cycle and requires advances in technology and physics for economical attractiveness. The optimal design was characterized through systems analyses for eventual conceptual engineering design. Results from the systems analysis are summarized, and a comparison with the high-field, D-T fueled ARIES-1 is included. 11 refs., 5 figs

1991-10-03

184

Anatomy of the Eye  

Science.gov (United States)

... the eye. A gelatinous substance known as the vitreous humor fills the cavity. This plays an important role in nourishing the inner structures of the eye. Light comes into the eye through the pupil and passes through the vitreous to be projected on the retina. Retina: The ...

185

Amblyopia: Lazy Eye Symptoms  

Science.gov (United States)

... Glasses, Contacts & LASIK Contact Lenses Colored Contact Lenses Eyeglasses IOLs Refractive Surgery & LASIK Sunglasses Living EyeSmart About Ophthalmologists Adults Under 40 Adults 40 to 60 Adults Over 60 Babies & Children Computer Usage Diabetes Diet & Nutrition Eye Injuries Eye Screening ...

186

Preventing Eye Injuries  

Science.gov (United States)

... Glasses, Contacts & LASIK Contact Lenses Colored Contact Lenses Eyeglasses IOLs Refractive Surgery & LASIK Sunglasses Living EyeSmart About Ophthalmologists Adults Under 40 Adults 40 to 60 Adults Over 60 Babies & Children Computer Usage Diabetes Diet & Nutrition Eye Injuries Eye Screening ...

187

Using Eye Makeup  

Science.gov (United States)

... Glasses, Contacts & LASIK Contact Lenses Colored Contact Lenses Eyeglasses IOLs Refractive Surgery & LASIK Sunglasses Living EyeSmart About Ophthalmologists Adults Under 40 Adults 40 to 60 Adults Over 60 Babies & Children Computer Usage Diabetes Diet & Nutrition Eye Injuries Eye Screening ...

188

Eye Injuries at Home  

Science.gov (United States)

... Glasses, Contacts & LASIK Contact Lenses Colored Contact Lenses Eyeglasses IOLs Refractive Surgery & LASIK Sunglasses Living EyeSmart About Ophthalmologists Adults Under 40 Adults 40 to 60 Adults Over 60 Babies & Children Computer Usage Diabetes Diet & Nutrition Eye Injuries Eye Screening ...

189

Eye and orbital cavity  

International Nuclear Information System (INIS)

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

1984-01-01

190

Lasik eye surgery - discharge  

Science.gov (United States)

LASIK is eye surgery that permanently changes the shape of the cornea (the clear covering on the front of the eye) in ... improves. At the first doctor visit after the surgery, the eye shield will be removed and the doctor will ...

191

Numerical investigation of the cavitational behaviour into a storage pump at off design operating points  

International Nuclear Information System (INIS)

The paper presents a new method for the analysis of the cavitational behaviour of hydraulic turbomachines. This new method allows determining the coefficient of the cavitation inception and the cavitation sensitivity of the turbomachines. We apply this method to study the cavitational behaviour of a large storage pump. By plotting in semi-logarithmic coordinates the vapour volume versus the cavitation coefficient, we show that all numerical data collapse in an exponential manner. This storage pump is located in a power plant and operating without the presence of the developed cavitation is vital. We investigate the behaviour of the pump from the cavitational point of view while the pump is operating for variable discharge. A distribution of the vapour volume upon the blade of the impeller is presented for all the four operating points. It can be seen how the volume of vapour evolves from one operating point to another. In order to study the influence of the cavitation phenomena upon the pump, the evolution of the pumping head against the cavitation coefficient is presented. That will show how the pumping head drops while the cavitation coefficient decreases. From analysing the data obtained from the numerical simulation it results that the cavitation phenomena is present for all the investigated operating points. By analysis of the slope of the curve describing the evolution of the vapour volume against the cavitation coefficient we determine the cavitation sensitivity of the pump for each operating point. It is showed that the cavitation sensitivity of the investigated storage pump increases while the flow rate decreases.

2010-08-01

192

Financial Aid for Eye Care  

Science.gov (United States)

Home » Health Information » Financial Aid for Eye Care Financial Aid for Eye Care Financial Aid for Eye Care PDF* Many state and national ... care. However, if you are in need of financial aid to assess or treat an eye problem, ...

193

General Didactics and Instructional Design: eyes like twins A transatlantic dialogue about similarities and differences, about the past and the future of two sciences of learning and teaching.  

Science.gov (United States)

Although General Didactics (GD) and Instructional Design (ID) have not shown many points of contact in the past, there are some obvious parellels from the perspective of their historical development. This will be examined in detail in this article. More specifically, we speak about model building, which has characterized General Didactics and Instructional Design for some decades. However, the models of General Didactics and Instructional Design are not problem-free with regard to the continuity and advancement of both disciplines. First, we will describe the historical roots of both disciplines and examine which elements of theory are of central importance. Second, we will try to answer the question of which kind of model building could be considered as predominant and what problems result from this predominance. In order to do this, we will describe empirical studies on the use of instructional models and discuss these studies from the perspective of the philosophy of science. Third, we will draw inferences for future processes of model building in order to prevent the same problems that happened in the past from happening again. Finally, we will discuss the issue of what General Didactics can learn from Instructional Design and vice versa. PMID:23961346

Zierer, Klaus; Seel, Norbert M

2012-01-01

194

Transportation of Bombay High crude: design considerations for pour point depressants  

Energy Technology Data Exchange (ETDEWEB)

Pour point depressants are ashless polymeric additives used for depression of pour point and viscosity of petroleum oils to facilitate their low temperature handling. In spite of the specificity associated with these additives with respect to crude oils, some of the common structural requirements of these additives prompted an investigation of these common requirements in relation to crude oils. X-ray diffraction studies of both the additives and the wax mixtures of crude oils indicated, apart from percentage crystallinity (100-amorphicity), conformational freedom of the backbone of the additive is essential for its activity. Such conformational freedom is, of course, also related to the degree of crystallinity. The solid waxes of the crude oils with carbon Nos. greater than 18 essentially pack in a hexagonal pattern and so do these long side chain polymeric additives. This results in c-crystallization but deliberate introduction of certain groups in the molecule lead to imperfections in the crystal lattice which destroy the gel strength.

Rao, V.S.B.; Thyagarajan, G.

1985-12-01

195

Design and Evaluation of Cell Phone Pointing Interface for Robot Control  

Digital Repository Infrastructure Vision for European Research (DRIVER)

In this work a pointing interface based on human gestures using a mobile phone accelerometer for interaction with robots is proposed. Through this interface the user can sketch stroke gestures on a computer screen using the cell phone accelerometer to make a selection and instruct a robot to perform a task. Selection, cancelation and movement, as well as some additional commands such as stop, pause and resume are supported. All the projected gestures are processed using known image analysis a...

Saso Koceski; Natasa Koceska; Ivica Kocev

2012-01-01

196

The Next Generation Nuclear Plant - Insights Gained from the INEEL Point Design Studies  

Energy Technology Data Exchange (ETDEWEB)

This paper provides the results of an assessment of two possible versions of the Next Generation Nuclear Plant (NGNP), a prismatic fuel type helium gas-cooled reactor and a pebble-bed fuel helium gas reactor. Insights gained regarding the strengths and weaknesses of the two designs are also discussed. Both designs will meet the three basic requirements that have been set for the NGNP: a coolant outlet temperature of 1000 C, passive safety, and a total power output consistent with that expected for commercial high-temperature gas-cooled reactors. Two major modifications of the current Gas Turbine- Modular Helium Reactor (GT-MHR) design were needed to obtain a prismatic block design with a 1000 C outlet temperature: reducing the bypass flow and better controlling the inlet coolant flow distribution to the core. The total power that could be obtained for different core heights without exceeding a peak transient fuel temperature of 1600 °C during a high or low-pressure conduction cooldown event was calculated. With a coolant inlet temperature of 490 °C and 10% nominal core bypass flow, it is estimated that the peak power for a 10-block high core is 686 MWt, for a 12-block high core is 786 MWt, and for a 14-block core is about 889 MWt. The core neutronics calculations showed that the NGNP will exhibit strongly negative Doppler and isothermal temperature coefficients of reactivity over the burnup cycle. In the event of rapid loss of the helium gas, there is negligible core reactivity change. However, water or steam ingress into the core coolant channels can produce a relatively large reactivity effect. Two versions of an annular pebble-bed NGNP have also been developed, a 300 and a 600 MWt module. From this work we learned how to design passively safe pebble bed reactors that produce more than 600 MWt. We also found a way to improve both the fuel utilization and safety by modifying the pebble design (by adjusting the fuel zone radius in the pebble to optimize the fuel-to-moderator ratio). We also learned how to perform design optimization calculations by using a genetic algorithm that automatically selects a sequence of design parameter sets to meet specified fitness criteria increasingly well. In the pebble-bed NGNP design work, we use the genetic algorithm to direct the INEEL’s PEBBED code to perform hundreds of code runs in less than a day to find optimized design configurations. And finally, we learned how to calculate cross sections more accurately for pebble bed reactors, and we identified research needs for the further refinement of the cross section calculations.

Philip E. MacDonald; A. M. Baxter; P. D. Bayless; J. M. Bolin; H. D. Gougar; R. L. Moore; A. M. Ougouag; M. B. Richards; R. L. Sant; J. W. Sterbentz; W. K. Terry

2004-08-01

197

Starting points and objectives for a design study of a radioactive waste repository to be mined in a salt dome  

International Nuclear Information System (INIS)

In close cooperation with Prof.Ir. P.Th. Velzeboer, Professor in Mining of the University of Technology in Delft, a design study has been made of a radioactive waste repository to be mined in a medium size salt dome. This article focuses on the starting points and objectives that formed the basis of this design study. The prime objective was a high degree of radiological and of conventional safety during the construction and operation of the disposal mine and a long-term isolation of the buried radionuclides once the facility was closed down and sealed. (Auth.)

1980-08-01

198

Dyslexic and normal readers' eye movements  

Digital Repository Infrastructure Vision for European Research (DRIVER)

Dyslexic and normal readers' eye movements were compared while tracking a moving fixation point and in reading. Contrary to previous reports, the dyslexic and normal readers did not differ in their number of saccades, percentage of regressions, or stability of fixations in the tracking task. Thus, defective oculomotor control was not associated with or a causal factor in dyslexia, and the dyslexics' abnormal eye movements in reading must be related to differences in higher cognitive processes...

Olson, Richard K.; Kliegl, Reinhold; Davidson, Brian J.

1983-01-01

199

Determination of eye movements from pupil tracking  

Digital Repository Infrastructure Vision for European Research (DRIVER)

The human eye is constantly moving even when it is maintaining a stable fixation point. Stable images on the retina rapidly saturate the photoreceptors and fade. The visual system needs of constant stimulation to which it adapts. These constant changes are achieved by fixation micromovements consisting of microtremors, drifts and microsaccades. Thus, accurate determination of pupil center is useful for precise eye tracking. We present a technique for pupil segmentation and contour analysis wh...

Roig Herna?ndez, Ana Bele?n; Espinosa Toma?s, Julia?n; Pe?rez Rodri?guez, Jorge; Mas Candela, David; Va?zquez Ferri, Carmen; Dome?nech Amigot, Begon?a; Herna?ndez Poveda, Consuelo; Miret Mari?, Juan Jose?; Illueca Contri, Carlos

2010-01-01

200

Through Our Parents' Eyes  

Science.gov (United States)

How does an institution help tell the story of the community it is located in? This type of endeavor can take many approaches, and the University of Arizona seems to have found a fantastic way to do so. Working with a variety of organizations and individuals throughout the greater Tucson and Southern Arizona community. Through Our Parents' Eyes: History & Culture of Southern Arizona was started in the mid-1990s. The project was designed to bring together the diverse human experiences of the region by drawing on a wide range of documents, oral histories, historic images, and video clips. The project and this website feature a number of teaching resources, regional histories, and primary documents for use by anyone interested in the region. Some of these resources have been collected into thematic presentations, including "Words & Place: Native Literature of the American Southwest" and "War Relocation Authority Camps in Arizona, 1942-1946".

 
 
 
 
201

A conceptual design study of point focusing thin-film solar concentrators  

Science.gov (United States)

Candidates for reflector panel design concepts, including materials and configurations, were identified. The large list of candidates was screened and reduced to the five most promising ones. Cost and technical factors were used in making the final choices for the panel conceptual design, which was a stiffened steel skin substrate with a bonded, acrylic overcoated, aluminized polyester film reflective surface. Computer simulations were run for the concentrator optics using the selected panel design, and experimentally determined specularity and reflectivity values. Intercept factor curves and energy to the aperture curves were produced. These curves indicate that surface errors of 2 mrad (milliradians) or less would be required to capture the desired energy for a Brayton cycle 816 C case. Two test panels were fabricated to demonstrate manufacturability and optically tested for surface error. Surface errors in the range of 1.75 mrad and 2.2 mrad were measured.

1981-11-01

202

Deployment Design of Wireless Sensor Network for Simple Multi-Point Surveillance of a Moving Target  

Digital Repository Infrastructure Vision for European Research (DRIVER)

In this paper, we focus on the problem of tracking a moving target in a wireless sensor network (WSN), in which the capability of each sensor is relatively limited, to construct large-scale WSNs at a reasonable cost. We first propose two simple multi-point surveillance schemes for a moving target in a WSN and demonstrate that one of the schemes can achieve high tracking probability with low power consumption. In addition, we examine the relationship between tracking probability and sensor den...

Kazuya Tsukamoto; Hirofumi Ueda; Hitomi Tamura; Kenji Kawahara; Yuji Oie

2009-01-01

203

Design and realization of a handheld vibrometer system for noncontact in-vivo detection of microvibrations of the human eye to determine the intraocular pressure (IOP)  

Science.gov (United States)

To allow measurements of the intraocular pressure (IOP) by glaucoma patients themselves (self-tonometry) a handheld-interferometer system for non-contact in vivo measurements of microvibrations of the human eye was realized. The measurement principle is based on the dependence of the resonance frequencies of the human eye on the IOP. To analyze this, the human eye is stimulated by ultrasonic waves and the induced microvibrations are measured with a vibrometer and processed by a DSP unit. Beside a stabilized diode laser and a low noise photodetector an exact three-dimensional positioning system had to be developed to guarantee reliable measurements. To investigate the corresponding requirements a camera-based system for the detection of human eye movements was developed and test series with several persons were made. Based on these results an adjustment unit was integrated in a miniaturized interferometer system: After a short self-adjusting procedure lateral to the setup by overlaying two targets of a highly sensitive optical system the correct measuring distance between the cornea and the vibrometer parallel to the optical axis is determined automatically by an astigmatic auto-focus system. With this handheld-vibrometer in vivo measurements with several test persons were made with very good results concerning the reliability and handling capability.

Gundlach, Arnd; Rawer, Rainer; Hey, Stefan; Stork, Wilhelm; Mueller-Glaser, Klaus-Dieter

2002-06-01

204

Design of intelligent distributed control systems: a dependability point of view  

Energy Technology Data Exchange (ETDEWEB)

The use of fieldbuses and the emergence of intelligent sensors and actuators are opening up new possibilities for distributed control systems, but are also introducing additional constraints in terms of achieving dependability objectives. The type of production environment will greatly determine the predominant criterion for an automatic control system, i.e. reliability, availability, maintainability, safety, etc. On the other hand, the choice of a fieldbus system will also depend on factors such as application size, data throughput, and integration of time considerations. Other important criteria include cost, confidentiality, and compatibility with existing equipment. Therefore, it appears essential that designers be given the means to assess dependability at each design step by integrating feedback from experience. Assessing dependability is too often limited to an evaluation at the end of the design process, which often involves reselecting previous choices. The main topic of this paper is to focus on the communication function which is a pivotal of intelligent distributed control systems. So this article is a synthesis of different aspects linked to the design of fieldbus based applications thanks to the contributors, who come from various fields. Consequently it highlights the main problem and give some ways to solve them.

Cauffriez, Laurent; Ciccotelli, Joseph; Conrard, Blaise; Bayart, Mireille

2004-04-01

205

Deployment Design of Wireless Sensor Network for Simple Multi-Point Surveillance of a Moving Target  

Directory of Open Access Journals (Sweden)

Full Text Available In this paper, we focus on the problem of tracking a moving target in a wireless sensor network (WSN, in which the capability of each sensor is relatively limited, to construct large-scale WSNs at a reasonable cost. We first propose two simple multi-point surveillance schemes for a moving target in a WSN and demonstrate that one of the schemes can achieve high tracking probability with low power consumption. In addition, we examine the relationship between tracking probability and sensor density through simulations, and then derive an approximate expression representing the relationship. As the results, we present guidelines for sensor density, tracking probability, and the number of monitoring sensors that satisfy a variety of application demands.

Yuji Oie

2009-05-01

206

Translation of Stem Cell Research: Points to Consider in Designing Preclinical Animal Studies  

Science.gov (United States)

Summary Stem cell-based therapies hold tremendous promise for the treatment of serious diseases and injuries. Although hematopoietic stem cell transplantation is routinely used as part of the treatment regime for some malignancies and genetic diseases, most stem cell-based therapeutic products are investigational and still require preclinical and clinical studies to support their many novel therapeutic uses. Because of the multiple sources of stem cells, the plethora of potential applications, and the novel mechanism of action of stem cell-based therapies, there is no single set of universal guidance documents that can be used to inform the preclinical development path for these therapeutics. Specific technical issues relating to the transplantation of human cells in animals, new delivery procedures, and laborious methods to characterize transplanted cells can present further challenges in the design and execution of preclinical animal studies for stem cell-based therapeutic products. In this article, we outline important parameters to guide the design of preclinical studies for stem cell-based therapeutics. In addition, we review the types of preclinical studies that should be considered depending on the nature and specific use of the intended stem cell therapeutic product. Finally, we describe important considerations in the design and execution of specific studies to monitor the efficacy, toxicity, biodistribution, and tumorigenicity of stem cell-based therapeutics.

Frey-Vasconcells, Joyce; Baum, Elona; Feigal, Ellen G.

2012-01-01

207

Robot design from a neuro-ethological point of view. Shinkei kodogaku kara mita robot  

Energy Technology Data Exchange (ETDEWEB)

The science concerning the method of obtaining the desirable information by adjusting the controllable quantity based on the measurement of the uncontrollable quantity is called cybernetics. The cybernetics is the most ideal image of the robot. The instinct of animals is supported by the nervous system. The science which deals with the nervous system of animals as a function of its instinct is called the neuro-ethology. In this sense, the neuro-ethology is identical to the cybernetics. The fundamental basis of robot design the design of the robot is therefore the neuro-ethology. The treatment of the dependent information about space and time in the auditory nervous system of animals was reviewed. The petuliarity of the auditory system, auditory as an interferometry, and the evolution of the auditory system was explained by taking the sonner system in bats as a prototype of the auditory system of animal. For further explanation of auditory system, the correspondence to the phonetic recognition of Homo-sapiens was also reviewed. It is important for design of the robot to investigate the mechanism to extract informations of the auditory nervous system in animals including Homo-sapiens. 19 refs., 10 figs.

Shimozawa, T. (Hokkaido Univ., Sapporo (Japan). Research Inst. of Applied Electricity)

1991-11-01

208

Individual eye model based on wavefront aberration  

Science.gov (United States)

Based on the widely used Gullstrand-Le Grand eye model, the individual human eye model has been established here, which has individual corneal data, anterior chamber depth and the eyeball depth. Furthermore, the foremost thing is that the wavefront aberration calculated from the individual eye model is equal to the eye's wavefront aberration measured with the Hartmann-shack wavefront sensor. There are four main steps to build the model. Firstly, the corneal topography instrument was used to measure the corneal surfaces and depth. And in order to input cornea into the optical model, high-order aspheric surface-Zernike Fringe Sag surface was chosen to fit the corneal surfaces. Secondly, the Hartmann-shack wavefront sensor, which can offer the Zernike polynomials to describe the wavefront aberration, was built to measure the wavefront aberration of the eye. Thirdly, the eye's axial lengths among every part were measured with A-ultrasonic technology. Then the data were input into the optical design software-ZEMAX and the crystalline lens's shapes were optimized with the aberration as the merit function. The individual eye model, which has the same wavefront aberrations with the real eye, is established.

Guo, Huanqing; Wang, Zhaoqi; Zhao, Qiuling; Quan, Wei; Wang, Yan

2005-03-01

209

Transform designs to chips, an end user point of view on mask making  

Science.gov (United States)

Mask is a tool required to replicate a set of complicated IC geometries numerous times producing chips in large volume. It is absolutely crucial to achieve high quality mask in accuracy and perfection. This paper focuses on technology needs which challenge mask-making capabilities including data preparation and Optical Proximity Correction (OPC), Critical Dimension (CD) / Line Edge Roughness (LER) control, alignment and defect elimination. The impact of lithography and mask making on the design and manufacturing of new products is discussed from an end user perspective. The paper emphasizes performance, precision and perfection and the necessity of the three p's for the continuation of Moore's law.

Chen, John Y.

2012-11-01

210

Teamwork for eye care  

Directory of Open Access Journals (Sweden)

Full Text Available Human resource development (HRD – the development of the people who deliver health care – has been identified as one of the key pillars of eye health delivery. HRD is one of the essential building blocks of the World Health Organization (WHO Global Action Plan: ‘Towards universal eye health’. The importance of HRD is also recognised beyond eye care, as can be seen in the WHO Health Systems approach.

M Babar Qureshi

2014-04-01

211

Improvements in packages comprising eye baths and eye lotions  

International Nuclear Information System (INIS)

A new packaged assembly comprising an eye bath and eye lotion is described. The eye bath is shaped for application to the eye; it has a rim portion formed so as to provide a smooth skin-contacting surface and is sealed to a lid at a position removed from the skin-contacting area. The eye bath is formed in a sterile condition and aseptically filled to an appropriate level with eye lotion by a blow moulding process. The eye bath and its contents are sterilised after sealing by radioactive sterilsation. This packaged assembly is an improvement over previous eye bath assemblies in that it allows the eye bath to be used in a sterile form. It is also more comfortable and convenient to use than other sterile forms of eye treatment such as eye drops or jets of eye wash. Furthermore, bathing the eye provides a more prolonged treatment. (U.K.)

1979-09-12

212

Design and simulation of 64 point FFT using Radix 4 algorithm for FPGA Implementation  

Directory of Open Access Journals (Sweden)

Full Text Available The Fast Fourier Transform (FFT is one of the rudimentary operations in field of digital signal, image processing and FFT processor is a critical block in all multicarrier systems used primarily in the mobile environment. Fast Fourier transform (FFT is an efficient implementation of the discrete Fourier transform (DFT. The portability requirement of these systems is mainly responsible for the need of low power FFT architectures. . In this study, the development of 64 point FFT, based on Decimation-In- Time (DIT domain using Radix-4 algorithm. The complex multiplier is one of the most power consuming blocks in the FFT processor. A significant property of the proposed method is that the critical path of the address generator is independent from the FFT transform length N, making it extremely efficient for large FFT transforms. The results confirm the speed and area advantages for large FFTs. Although only radix-4 FFT address generation is presented in the paper, it can be used for higher radix FFT

K.Sreekanth Yadav

2013-02-01

213

Design and Analysis of an Extended Mission of CE-2: From Lunar orbit to Sun-Earth L2 point  

Science.gov (United States)

Being a part of Chinese Lunar Exploration Program, CE-2 was launched on 1 Oct.2010. CE-2 probe left lunar orbit for the Sun-Earth Lagrangian point L2 to test the tracking and control network after completing its primary objective. It entered orbit around Sun-Earth L2 on 25 August 2011, and is expected to remain there until the end of 2012. In this paper, we systematically discuss the trajectory design problem of this mission, and present the target Lissajous orbit of Sun-Earth L2 point based on the full ephemeris model. For complicated dynamics system of Sun-Earth-Moon-spacecraft, we decouple it in two different restricted three-body problems: Sun-Earth+Moon RTBP and the Earth-Moon one. We design the low-energy transfer trajectory in double three-body systems of Sun-Earth and Earth-Moon model by using invariant manifolds theory. Finally, we propose the basic correction strategy of transfer trajectory on basis of engineering constraints and mission requirements. The results of flight test show that the tajectory design of CE-2 mission is accurate and feasible.

Dong, Qiao

2012-07-01

214

Point of View: Intelligent Design: Jonathan Wells and the Tree of Life  

Science.gov (United States)

In recent years, the intelligent design (ID) movement has been very successful in attracting the attention of the general public. The ID movement is centered predominantly at the Center for Science and Culture in the very conservative think tank, the Discovery Institute, of Seattle, Washington. It has gained this attention by completely bypassing scientific channels and going directly to the general public, primarily in the form of op-ed articles, talk-show and TV appearances, and by making their anti-evolution books and video documentaries widely available, especially to school administrators, school boards, teachers, and legislators. The defeat of ID in the highly publicized Dover, Pennsylvania trial will not slow the movement down.

Gregg, Thomas

2007-07-01

215

A novel approach for designing simple point charge models for liquid water with three interaction sites.  

Science.gov (United States)

A simultaneous improvement of the diffusion and dielectric properties of the simple point charge (SPC) model for liquid water appears to be very difficult with conventional reparametrization of the commonly used Lennard-Jones and Coulomb interaction functions and without including a self-energy correction in the effective pair-potential as is done in the SPC/E model. Here, a different approach to circumvent this problem is presented. A short-range interaction term, which corrects the oxygen-oxygen energy at small distances by small amounts of energy, was introduced in the nonbonded interaction function. This additional force-field term allows to derive new parameter sets for SPC-like water models that yield better agreement with experimental data on liquid water. Based on previous investigations of the force-field parameter dependence of the water properties of SPC-like models, the necessary parameter changes to obtain a lower diffusion coefficient and a larger dielectric permittivity were specified and accordingly six new models were developed. They all represent an improvement over SPC in terms of structural and diffusional properties, four of them show better dielectric properties also. One model, SPC/S, has been characterized in more detail, and represents most properties of liquid water better than SPC while avoiding the larger discrepancies with experimental values regarding density, thermal compressibility, energy, and free energy of the SPC/E model. We conclude that the use of a simple, short-ranged additional oxygen-oxygen interaction term makes a simultaneous improvement of the diffusion coefficient and the dielectric properties of water feasible. PMID:12759908

Glättli, Alice; Daura, Xavier; Van Gunsteren, Wilfred F

2003-07-15

216

Super-resolution imaging using multi- electrode CMUTs: theoretical design and simulation using point targets.  

Science.gov (United States)

This paper investigates a low computational cost, super-resolution ultrasound imaging method that leverages the asymmetric vibration mode of CMUTs. Instead of focusing on the broadband received signal on the entire CMUT membrane, we utilize the differential signal received on the left and right part of the membrane obtained by a multi-electrode CMUT structure. The differential signal reflects the asymmetric vibration mode of the CMUT cell excited by the nonuniform acoustic pressure field impinging on the membrane, and has a resonant component in immersion. To improve the resolution, we propose an imaging method as follows: a set of manifold matrices of CMUT responses for multiple focal directions are constructed off-line with a grid of hypothetical point targets. During the subsequent imaging process, the array sequentially steers to multiple angles, and the amplitudes (weights) of all hypothetical targets at each angle are estimated in a maximum a posteriori (MAP) process with the manifold matrix corresponding to that angle. Then, the weight vector undergoes a directional pruning process to remove the false estimation at other angles caused by the side lobe energy. Ultrasound imaging simulation is performed on ring and linear arrays with a simulation program adapted with a multi-electrode CMUT structure capable of obtaining both average and differential received signals. Because the differential signals from all receiving channels form a more distinctive temporal pattern than the average signals, better MAP estimation results are expected than using the average signals. The imaging simulation shows that using differential signals alone or in combination with the average signals produces better lateral resolution than the traditional phased array or using the average signals alone. This study is an exploration into the potential benefits of asymmetric CMUT responses for super-resolution imaging. PMID:24158286

You, Wei; Cretu, Edmond; Rohling, Robert

2013-11-01

217

Improving eye care in the primary health care setting  

Directory of Open Access Journals (Sweden)

Full Text Available One of the challenges facing primary health care in South Africa is the delivery of quality eye care to all South Africans. In this regard the role of the primary health care worker, as the first point of contact, is crucial. This paper reports on the problems primary health care workers experience in providing quality eye care in Region B of the Free State. Problems identified by those involved in the study include the cumbersome referral system, the unavailability of appropriate medicine at clinics, the insufficient knowledge of primary health care workers regarding eye conditions and the lack of communication between the various eye care service providers. Suggestions to address the problems identified included more in-service training of primary health care workers regarding eye conditions, liaison with NGO’s providing eye care, decentralisation of services and the establishment of an eye care committee in the region.

M de Wet

2000-09-01

218

Initial Scaling Studies and Conceptual Thermal Fluids Experiments for the Prismatic NGNP Point Design  

Energy Technology Data Exchange (ETDEWEB)

The objective of this report is to document the initial high temperature gas reactor scaling studies and conceptual experiment design for gas flow and heat transfer. The general approach of the project is to develop new benchmark experiments for assessment in parallel with CFD and coupled CFD/ATHENA/RELAP5-3D calculations for the same geometry. Two aspects of the complex flow in an NGNP are being addressed: (1) flow and thermal mixing in the lower plenum ("hot streaking" issue) and (2) turbulence and resulting temperature distributions in reactor cooling channels ("hot channel" issue). Current prismatic NGNP concepts are being examined to identify their proposed flow conditions and geometries over the range from normal operation to decay heat removal in a pressurized cooldown. Approximate analyses are being applied to determine key non-dimensional parameters and their magnitudes over this operating range. For normal operation, the flow in the coolant channels can be considered to be dominant forced convection with slight transverse property variation. The flow in the lower plenum can locally be considered to be a situation of multiple buoyant jets into a confined density-stratified crossflow -- with obstructions. Experiments are needed for the combined features of the lower plenum flows. Missing from the typical jet experiments are interactions with nearby circular posts and with vertical posts in the vicinity of vertical walls - with near stagnant surroundings at one extreme and significant crossflow at the other. Two heat transfer experiments are being considered. One addresses the "hot channel" problem, if necessary. The second experiment will treat heated jets entering a model plenum. Unheated MIR (Matched-Index-of-Refraction) experiments are first steps when the geometry is complicated. One does not want to use a computational technique which will not even handle constant properties properly. The MIR experiment will simulate flow features of the paths of jets as they mix in flowing through the array of posts in a lower plenum en route to the single exit duct. Initial conceptual designs for such experiments are described.

D. M. McEligot; G. E. McCreery

2004-09-01

219

What Is Dry Eye?  

Medline Plus

Full Text Available ... Glasses, Contacts & LASIK Contact Lenses Colored Contact Lenses Eyeglasses IOLs Refractive Surgery & LASIK Sunglasses Living EyeSmart About Ophthalmologists Adults Under 40 Adults 40 to 60 Adults Over 60 Babies & Children Computer Usage Diabetes Diet & Nutrition Eye Screening Guidelines Home ...

220

What Is Dry Eye?  

Science.gov (United States)

... Glasses, Contacts & LASIK Contact Lenses Colored Contact Lenses Eyeglasses IOLs Refractive Surgery & LASIK Sunglasses Living EyeSmart About Ophthalmologists Adults Under 40 Adults 40 to 60 Adults Over 60 Babies & Children Computer Usage Diabetes Diet & Nutrition Eye Screening Guidelines Home ...

 
 
 
 
221

The Liminal Eye.  

Science.gov (United States)

Discusses interrelations between painting and video art. Argues that once the surface of the painting is thought of in relation to the membrane of the eye as if the painting's surface were part of the eye itself, the painting's surface would have to be thought of as a membrane of visible excitation that is hard to separate from vision. (SR)

Rapaport, Herman

1995-01-01

222

Eye-Tracking  

Digital Repository Infrastructure Vision for European Research (DRIVER)

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

2006-01-01

223

LASIK - Laser Eye Surgery  

Medline Plus

Full Text Available ... Surgery Procedures Find An Eye M.D. Enter zip code here Search by Name, City, State or ... Subscribe for Eye Health Info Sign up for our monthly e-mail newsletter with tips and information on preserving your ...

224

LASIK - Laser Eye Surgery  

Medline Plus

Full Text Available ... may need this information if you have other eye surgery later, such as cataract surgery. Bring this "K ... eyeglasses or contact lenses. Next Page: Alternative Refractive Surgery Procedures Find An Eye M.D. Enter zip code here Search by ...

225

Medicare Benefits and Your Eyes  

Science.gov (United States)

Medicare benefits and your eyes Eye Health is Important! As you age, your risk for vision impairment ... on the arrows below for detailed information about Medicare benefits and your eyes. Request a Free Copy ...

226

Finding an Eye Care Professional  

Science.gov (United States)

... an Eye Care Professional Finding an Eye Care Professional Finding an Eye Care Professional PDF* The National ... website can be addressed to the NEI Website Manager . NIH...Turning Discovery Into Health ®

227

The Dkk1 dose is critical for eye development  

DEFF Research Database (Denmark)

During mammalian ocular development, several signaling pathways control the spatiotemporal highly defined realization of the three-dimensional eye architecture. Given the complexity of these inductive signals, the developing eye is a sensitive organ for several diseases. In this study, we investigated a Dkk1+/- haploinsufficiency during eye development, resulting in coloboma and anterior eye defects, two common developmental eye disorders. Dkk1 impacts eye development from a defined developmental time point on, and is critical for lens separation from the surface ectoderm via β-catenin mediated Pdgfrα and E-cadherin expression. Dkk1 does not impact the dorso ventral retina patterning in general but is critical for Shh dependent Pax2 extension into the midline region. The described results also indicate that the retinal Dkk1 dose is critical for important steps during eye development, such as optic fissure closure and cornea formation. Further analysis of the relationship between Dkk1 and Shh signaling revealed that Dkk1 and Shh coordinatively control anterior head formation and eye induction. During eye development itself, retinal Dkk1 activation is depending on cilia mediated Gli3 regulation. Therefore, our data essentially improve the knowledge of coloboma and anterior eye defects, which are common human eye developmental defects.

Dr Lieven, Oliver Wilm; Rüther, Ulrich

2011-01-01

228

The role of Pax genes in eye evolution.  

Science.gov (United States)

Anatomically widely different designs of animal eyes have long been thought to arise independently multiple times during evolution. This morphology-based view has been challenged by the identification of a highly conserved transcription factor Pax6 that plays a key role in eye development in both flies and mammals. The origin of Pax genes predates the origin of eyes and the nervous system since a PaxB-like gene, belonging to the Pax2/5/8 gene subfamily, was identified in sponge lacking nervous system. Structurally similar PaxB gene is implicated in visual system development in jellyfish, the most basal organism possessing complex eyes. The widespread use of Pax genes in the genetic program underlying eye formation throughout the animal kingdom raises a question why certain transcription factors have been frequently redeployed to build eyes. A model is proposed that provides a plausible explanation for the apparently ancient role of Pax genes in eye evolution. PMID:18331895

Kozmik, Zbynek

2008-03-18

229

Data eye monitor method and apparatus  

Science.gov (United States)

An apparatus and method for providing a data eye monitor. The data eye monitor apparatus utilizes an inverter/latch string circuit and a set of latches to save the data eye for providing an infinite persistent data eye. In operation, incoming read data signals are adjusted in the first stage individually and latched to provide the read data to the requesting unit. The data is also simultaneously fed into a balanced XOR tree to combine the transitions of all incoming read data signals into a single signal. This signal is passed along a delay chain and tapped at constant intervals. The tap points are fed into latches, capturing the transitions at a delay element interval resolution. Using XORs, differences between adjacent taps and therefore transitions are detected. The eye is defined by segments that show no transitions over a series of samples. The eye size and position can be used to readjust the delay of incoming signals and/or to control environment parameters like voltage, clock speed and temperature.

Gara, Alan G. (Mount Kisco, NY); Marcella, James A. (Rochester, MN); Ohmacht, Martin (Yorktown Heights, NY)

2012-01-31

230

Design and Integration of an All-Magnetic Attitude Control System for FASTSAT-HSV01's Multiple Pointing Objectives  

Science.gov (United States)

The FASTSAT-HSV01 spacecraft is a microsatellite with magnetic torque rods as it sole attitude control actuator. FASTSAT s multiple payloads and mission functions require the Attitude Control System (ACS) to maintain Local Vertical Local Horizontal (LVLH)-referenced attitudes without spin-stabilization, while the pointing errors for some attitudes be significantly smaller than the previous best-demonstrated for this type of control system. The mission requires the ACS to hold multiple stable, unstable, and non-equilibrium attitudes, as well as eject a 3U CubeSat from an onboard P-POD and recover from the ensuing tumble. This paper describes the Attitude Control System, the reasons for design choices, how the ACS integrates with the rest of the spacecraft, and gives recommendations for potential future applications of the work.

DeKock, Brandon; Sanders, Devon; Vanzwieten, Tannen; Capo-Lugo, Pedro

2011-01-01

231

Investigation of the SQUBIC phase mask design for depth-invariant widefield microscopy point-spread function engineering  

Science.gov (United States)

Point-spread function engineering (PSF), achieved by placing a phase mask at the pupil plane of the imaging lens to encode the wavefront emerging from an imaging system, can be employed to reduce the impact of spherical aberration (SA) in 3D microscopy. In a previous study, the effect of SA on a confocal scanning microscope using a squared cubic phase mask (SQUBIC) was investigated using computer simulations. Here the effect of the SQUBIC design parameter on the insensitivity of the engineered PSF to SA is investigated using a metric based on the second-order moment of the axial variability of the PSF. We show that it is possible to find the optimum SQUBIC for the insensitization to SA.

Doblas, Ana; King, Sharon V.; Patwary, Nurmohammed; Saavedra, Genaro; Martínez-Corral, Manuel; Preza, Chrysanthe

2014-03-01

232

The construction of individual eye model based on eye's wavefront aberration measurement  

Science.gov (United States)

Based on the widely used Gullstrand-Le Grand eye model, the individual human eye model has been established here, which has individual corneal data, anterior chamber depth and the eyeball depth. Furthermore the foremost thing is that the wavefront aberration calculated from the individual eye model is equal to the eye's wavefront aberration measured with the Hartmann-shack wavefront sensor. There were four main steps to build the model. Firstly, the corneal topography instrument was used to measure the corneal surfaces and depth. And in order to input cornea into the optical model, high order aspheric surface-Zernike Fringe Sag surface was chosen to fit the corneal surfaces. Secondly, the Hartmann-shack wavefront sensor, which can offer the Zernike polynomials to describe the wavefront aberration, was built to measure the wavefront aberration of the eye. Thirdly, the eye's axial lengths among every part were measured with A-ultrasonic technology. Then the data were input into the optical design software -ZEMAX and the crystalline lens's shapes were optimized with the aberration as the merit function. The individual eye model, which has the same wavefront aberrations with the real eye, is established.

Wang, Zhao-Qi; Guo, Huan-Qing

2005-08-01

233

LASIK - Laser Eye Surgery  

Medline Plus

Full Text Available ... effects to go away. LASIK risks and side effects LASIK, like any surgery, has potential risks and ... Alternative Refractive Surgery Procedures Find An Eye M.D. Enter zip code here Search by Name, City, ...

234

LASIK eye surgery  

Science.gov (United States)

... objects may appear fuzzy or gray Dry eyes Glare or haloes Light sensitivity Night driving problems Patches ... it may not relieve other symptoms such as glare, haloes, or problems with night driving. Often, these ...

235

Toxoplasmosis (and the Eye)  

Science.gov (United States)

Toxoplasmosis Read in Chinese What is toxoplasmosis? Toxoplasmosis is an infection with the protozoan intracellular parasite Toxoplasma gondii. In the eye, Toxoplasma infections frequently cause significant inflammation and subsequent ...

236

Normal Eye Anatomy  

Science.gov (United States)

... 4M, TIFF) 300 dpi (1.4M, TIFF) Description: Normal adult lens in cross section (slit lamp picture). ... TIFF) 300 dpi (250K, TIFF) Description: Fundus photograph-normal retina Credit: National Eye Institute, National Institutes of ...

237

Diabetes - Eye Complications  

Medline Plus

Full Text Available ... become blocked. Diabetic Retinopathy The weakening of the blood vessels of the eyes is known as diabetic retinopathy. “Retinopathy” means disease of the retina. It is the most serious ...

238

LASIK - Laser Eye Surgery  

Medline Plus

Full Text Available ... even with "no rub" solutions. Eye Protection at Home Every household should have at least one pair ... plan to have someone drive him or her home after the procedure and then take a nap ...

239

Diabetes - Eye Complications  

Medline Plus

Full Text Available ... material, it may become out of date over time. It is important that you rely on the advice of a ... glaucoma. Prevention through successful management of diabetes helps prevent and delay these eye ...

240

LASIK - Laser Eye Surgery  

Medline Plus

Full Text Available ... Maintaining Your Sight with Diabetes Sports and Eye Protection Eyesight Risks for ... change may be all you need to improve your vision with early-stage cataracts. Protect your ...

 
 
 
 
241

What Is Dry Eye?  

Medline Plus

Full Text Available ... Reduced Vision Tearing See all Symptoms > Glasses, Contacts & LASIK Contact Lenses Colored Contact Lenses Eyeglasses IOLs Refractive Surgery & LASIK Sunglasses Living EyeSmart About Ophthalmologists Adults Under 40 ...

242

Diabetes - Eye Complications  

Medline Plus

Full Text Available ... have other eye problems such as blurred vision, cataract, and glaucoma. People with diabetes may have blurry ... is back to normal. All people can get cataract, especially when they get older. However, diabetic patients ...

243

Multimodal eye recognition  

Science.gov (United States)

Multimodal biometrics use more than one means of biometric identification to achieve higher recognition accuracy, since sometimes a unimodal biometric is not good enough used to do identification and classification. In this paper, we proposed a multimodal eye recognition system, which can obtain both iris and sclera patterns from one color eye image. Gabor filter and 1-D Log-Gabor filter algorithms have been applied as the iris recognition algorithms. In sclera recognition, we introduced automatic sclera segmentation, sclera pattern enhancement, sclera pattern template generation, and sclera pattern matching. We applied kernelbased matching score fusion to improve the performance of the eye recognition system. The experimental results show that the proposed eye recognition method can achieve better performance compared to unimodal biometric identification, and the accuracy of our proposed kernel-based matching score fusion method is higher than two classic linear matching score fusion methods: Principal Component Analysis (PCA) and Linear Discriminant Analysis (LDA).

Zhou, Zhi; Du, Yingzi; Thomas, N. L.; Delp, Edward J., III

2010-04-01

244

LASIK - Laser Eye Surgery  

Medline Plus

Full Text Available ... your contacts, even with "no rub" solutions. Eye Protection at Home Every household should have at least ... the age-related loss of close-up focusing power. How the LASIK procedure works LASIK is performed ...

245

Diabetes - Eye Complications  

Medline Plus

Full Text Available ... eyes are small. When they become weak, they leak, burst, or become blocked. Diabetic Retinopathy The weakening ... by diabetes. Blood vessels of the retina may leak if they are weak. This can cause swelling ...

246

Unusual eye injuries  

Directory of Open Access Journals (Sweden)

Full Text Available Purpose: The analysis of ten unusual eye injuries, and the discussion of appropriate preventive measures. Case outline: Ten patients hospitalized at the Clinic of Eye Diseases, Clinical Center of Serbia, Belgrade, in the period from January 2000. to December 2009. were presented. Following data were taken in account: sex and age of the patient, injured eye, the mechanism of injury, type of the injury, applied treatment and final visual acuity. The circumstances of the eye injuring of ten patients were described. The eye injuries in all cases occurred in a bizarre way and they were severe enough to require hospital admission. The surgery was necessary in seven patients. Three injured eyes resulted in blindness, and two additional had subnormal vision. Conclusion: In three quarters of discussed cases injuries can be avoided. It is necessary to implement protective measures constantly and consistently and to think about the possible consequences of certain activities. Particular attention should be paid on safety of children. The iatrogenic injuries require special consideration.

Jovanovi? Miloš

2012-01-01

247

Dose effects of gamma radiation sterilization on antibiotic eye ointment  

International Nuclear Information System (INIS)

Radiation effects of Co-60 gamma rays on some eye ointment base such as plastibase, cetyl alcohol, liquid paraffin, vaselin album, adeps lanae and tetracycline eye ointment in plastibase were examined by physico-chemical determinations. Parameters observed were color changes, pH, melting point, viscosity, iodine value, acid value and TLC, uv-spectrophotometric examination. Microbiological examinations were carried out to determine the degree of initial contamination of unirradiated eye ointment. Radiation dose used were radiation sterilization doses of 2 and 4 Mrad and storage time was 3 and 6 months. The results showed that the iodine value of tetracycline eye ointment in plastibase and eye ointment bases such as plastibase, vaselin album, liquid paraffin, cetyl alcohol, adeps lanae, changed significantly. Viscosity examination showed non-significant results, except for vaselin album and liquid paraffin irradiated at 4 Mrad. Microbiological examinations showed that some unirradiated eye ointment were contaminated by a few kinds of microbes. (author)

1980-07-01

248

Investigation of non-quarter wave design on multilayer optical thin film coatings from a heat transfer point of view  

Science.gov (United States)

In this study multilayer thin film optical coatings, which are indispensable parts of optical systems are investigated from a heat transfer point of view. Laser irradiation induced temperature distribution on a multilayer coating stack is obtained by discretizing the heat diffusion equation using the finite volume method. In order to obtain mathematical representation of the energy flow and Electric Field Intensity (EFI) through the stack, Maxwell equations are solved by using the commercial software MacLeod®. Laser energy, which is absorbed by the multilayer stack in terms of heat, is calculated as a function of space and time by using the computed EFI, coating materials' optical properties and Gaussian laser beam parameters. Computed heat load is used in the finite volume solver ANSYS FLUENT® through a user defined function. Temperature distribution on a 19 layer HR multilayer coating stack irradiated by 1064 nm laser beam are obtained for both quarter wave and non-quarter wave designed configurations. Results of numerical simulations show that maximum temperature rise is seen in the first high index layer for quarter wave design (QWD). In addition to that, high temperatures are also seen in film/film interfaces, which is associated to both EFI distribution on the stack and wide differences in material properties between high and low index film layers. Non-quarter wave design (NQWD) is seen to be successful in decreasing temperatures at high index layers and at film/film interfaces. But it also changes the EFI distribution inside the multilayer stack, increasing absorbed laser energy and resulting in higher temperatures at modified low index layers.

Ocak, Mustafa; Sert, Cüneyt; Okutucu, Tuba Ö.

2013-11-01

249

Case study: improving the management of eye care programmes  

Digital Repository Infrastructure Vision for European Research (DRIVER)

Nigeria is a federation of 36 administrative States, which each have a mandate to deliver health care to their population. Sightsavers International has been supporting four State ministries of health (Cross River, Kaduna, Kwara, and Sokoto) in implementing programmes designed to provide comprehensive eye care services.Previously, eye care had been limited to services in big hospitals in the largest cities, which were inaccessible to the general population.These new eye care programmes have b...

2008-01-01

250

Red eye unresponsive to treatment.  

Digital Repository Infrastructure Vision for European Research (DRIVER)

Red eyes that fail to respond quickly and completely to topical antibiotic treatment require more extensive evaluation to relieve the symptoms and avert possible sight-threatening complications. The initial differential diagnosis of red eye, which includes iritis, acute glaucoma, keratitis and corneal ulcer, and rarer disorders, must be reexamined. A commonly misdiagnosed cause of red eye is the dry eye syndrome. As a primary or secondary problem, the dry eye syndrome must be treated appropri...

Michelson, P. E.

1997-01-01

251

Identification system by eye retinal pattern  

International Nuclear Information System (INIS)

Identification system by eye retinal pattern is introduced from the view-point of history of R and D, measurement, apparatus, evaluation tests, safety and application. According to our evaluation tests, enrolling time is approximately less than 1 min, verification time is a few seconds and false accept rate is 0 %. Evaluation tests at Sandia National Laboratories in USA show the comparison data of false accept rates such as 0 % for eye retinal pattern, 10.5 % for finger-print, 5.8 % for signature dynamics and 17.7 % for speaker voice. The identification system by eye retinal pattern has only three applications in Japan, but there has been a number of experience in USA. This fact suggests that the system will become an important means for physical protections not only in nuclear field but also in other industrial fields in Japan. (author)

1987-01-01

252

A randomised controlled trial investigating the effect of nutritional supplementation on visual function in normal, and age-related macular disease affected eyes: design and methodology [ISRCTN78467674  

Directory of Open Access Journals (Sweden)

Full Text Available Abstract Background Age-related macular disease is the leading cause of blind registration in the developed world. One aetiological hypothesis involves oxidation, and the intrinsic vulnerability of the retina to damage via this process. This has prompted interest in the role of antioxidants, particularly the carotenoids lutein and zeaxanthin, in the prevention and treatment of this eye disease. Methods The aim of this randomised controlled trial is to determine the effect of a nutritional supplement containing lutein, vitamins A, C and E, zinc, and copper on measures of visual function in people with and without age-related macular disease. Outcome measures are distance and near visual acuity, contrast sensitivity, colour vision, macular visual field, glare recovery, and fundus photography. Randomisation is achieved via a random number generator, and masking achieved by third party coding of the active and placebo containers. Data collection will take place at nine and 18 months, and statistical analysis will employ Student's t test. Discussion A paucity of treatment modalities for age-related macular disease has prompted research into the development of prevention strategies. A positive effect on normals may be indicative of a role of nutritional supplementation in preventing or delaying onset of the condition. An observed benefit in the age-related macular disease group may indicate a potential role of supplementation in prevention of progression, or even a degree reversal of the visual effects caused by this condition.

Eperjesi Frank

2003-10-01

253

Effect of Education Sessions of a Structured School Eye Screening Programme on Indian Schoolteachers' Knowledge and Responsibility for Children's Eye Health  

Science.gov (United States)

Objective: To evaluate the effect of education sessions on Indian schoolteacher awareness of childhood eye health issues, responsibility for children's eye health, and successful participation in a teacher-led eye screening health intervention programme in primary schools aimed at addressing avoidable childhood blindness in India. Design

Thummalapalli, Rohit; Williams, Jachin D.; Khoshnood, Kaveh; Salchow, Daniel J.; Forster, Susan H.

2013-01-01

254

Powered wheelchair controlled by eye-tracking system  

Digital Repository Infrastructure Vision for European Research (DRIVER)

In this paper, we use the optical-type eye tracking system to control powered wheelchair. The userís eye movements are translated to screen position using the optical-type eye tracking system. The pupil-tracking goggles with a video CCD camera and a frame grabber analyzes a series of human pupil images when the user is gazing at the screen. A new calibration algorithm is then used to determine the direction of the eye gaze in real time. We design an interface with nine command zones to...

2006-01-01

255

A 99 Dollar Head-Mounted Eye Tracker  

Digital Repository Infrastructure Vision for European Research (DRIVER)

Head-mounted eye-trackers are powerful research tools to study attention processes in various contexts. Most existing commercial solutions are still very expensive, limiting the current use of this technology. We present a hardware design to build, at low cost, a camera-based head-mounted eye tracker using two cameras and one infrared LED. A Playstation Eye camera (PEye) is fixed on an eyeglasses frame and positioned under one eye to track its movements. The filter of the PEye is replaced by ...

Marko, Youri; Mazzei, Andrea; Kaplan, Fre?de?ric; Dillenbourg, Pierre

2011-01-01

256

Dynamic Eye Model.  

Science.gov (United States)

Instructions (with diagrams and parts list) are provided for constructing an eye model with a pliable lens made from a plastic bottle which can vary its convexity to accommodate changing positions of an object being viewed. Also discusses concepts which the model can assist in developing. (Author/SK)

Journal of Science and Mathematics Education in Southeast Asia, 1981

1981-01-01

257

Diabetes - Eye Complications  

Medline Plus

Full Text Available ... for your specific condition. ©1995-2012, The Patient Education Institute, Inc. www.X-Plain.com db010105 Last reviewed: 11/29/2012 3 Summary People with diabetes are more likely to develop eye problems such as retinopathy, cataract, and glaucoma. Prevention through ...

258

Pursuit Eye Movements  

Science.gov (United States)

When viewing objects, primates use a combination of saccadic and pursuit eye movements to stabilize the retinal image of the object of regard within the high-acuity region near the fovea. Although these movements involve widespread regions of the nervous system, they mix seamlessly in normal behavior. Saccades are discrete movements that quickly direct the eyes toward a visual target, thereby translating the image of the target from an eccentric retinal location to the fovea. In contrast, pursuit is a continuous movement that slowly rotates the eyes to compensate for the motion of the visual target, minimizing the blur that can compromise visual acuity. While other mammalian species can generate smooth optokinetic eye movements - which track the motion of the entire visual surround - only primates can smoothly pursue a single small element within a complex visual scene, regardless of the motion elsewhere on the retina. This ability likely reflects the greater ability of primates to segment the visual scene, to identify individual visual objects, and to select a target of interest.

Krauzlis, Rich; Stone, Leland; Null, Cynthia H. (Technical Monitor)

1998-01-01

259

The Eyes Have It.  

Science.gov (United States)

Describes a lesson in which students drew their own self-portraits following three criteria: (1) use mixed media; (2) emphasize expressiveness of facial features; and (3) focus on the eyes. Asserts that students were not allowed to use an opaque projector or copy from photographs. Reports the students had difficulty drawing the planes of their…

Greenman, Geri

1998-01-01

260

LASIK - Laser Eye Surgery  

Medline Plus

Full Text Available ... you have LASIK. If these materials raise any questions for you, be sure to discuss these questions with your Eye M.D. Is LASIK For ... it completed and keep it for future use. Questions to Ask When Considering LASIK If you are ...

 
 
 
 
261

What Is Dry Eye?  

Medline Plus

Full Text Available ... information on preserving your healthy vision. Privacy Policy Email address © 2014 American Academy of Ophthalmology medical disclaimer privacy policy sponsorship & advertising policies about us For Medical Providers EyeWiki contact us sitemap Reproducing text or images from this ...

262

LASIK - Laser Eye Surgery  

Medline Plus

Full Text Available ... contact lenses. If sharp, detailed 20/20 vision is essential for your job or leisure activities, consider whether 20/40 ... M.D. Enter zip code here Search by Name, City, State or Subspecialty > Ask An Eye M.D. Enter your question here... Browse Top Answers > Privacy Policy > Featured ...

263

Practical evaluation of an interior point three-D filter line search method using engineering design problems  

Digital Repository Infrastructure Vision for European Research (DRIVER)

We present a primal-dual interior point method for nonlinear optimization that relies on a line search filter strategy to allow convergence from poor starting points. The filter technique has already been adapted to interior point methods in different ways. Our filter relies on three components. Each entry in the filter includes the feasibility measure, the centrality measure and the barrier objective function value as the optimality measure. Numerical experiments carried...

Costa, M. Fernanda P.; Fernandes, Edite Manuela Da G. P.

2009-01-01

264

Operational procedure for computer program for design point characteristics of a gas generator or a turbojet lift engine for V/STOL applications  

Science.gov (United States)

The computer program described calculates the design-point characteristics of a gas generator or a turbojet lift engine for V/STOL applications. The program computes the dimensions and mass, as well as the thermodynamic performance of the model engine and its components. The program was written in FORTRAN 4 language. Provision has been made so that the program accepts input values in either SI Units or U.S. Customary Units. Each engine design-point calculation requires less than 0.5 second of 7094 computer time.

Krebs, R. P.

1972-01-01

265

If I Had - Dry Eyes  

Medline Plus

Full Text Available ... Adults with Severe COPD VIDEO: If I Had - Dry Eyes - Dr. Penny Asbell, MD, FACS, MBA, Professor of ... Back to Home Page VIDEO: If I Had - Dry Eyes - Dr. Penny Asbell, MD, FACS, MBA, Professor of ...

266

Childhood Eye Diseases and Conditions  

Science.gov (United States)

... to Z Age-related Macular Degeneration (AMD) Allergies Amblyopia (Lazy Eye) Astigmatism Bacterial Keratitis Bell's Palsy Blepharitis Cataracts Contact ... be examined by an ophthalmologist (Eye M.D.). Amblyopia What it is: Amblyopia is a term used ...

267

If I Had - Dry Eyes  

Medline Plus

Full Text Available ... COPD VIDEO: If I Had - Dry Eyes - Dr. Penny Asbell, MD, FACS, MBA, Professor of Ophthalmology, Mount ... Page VIDEO: If I Had - Dry Eyes - Dr. Penny Asbell, MD, FACS, MBA, Professor of Ophthalmology, Mount ...

268

Eye Bank Association of America  

Science.gov (United States)

... to content Skip to Navigation Find an Eye Bank Near You MEMBER LOGIN ALERT (April 11, 2014): ... is the nationally-recognized accrediting body for eye banks. Since 1961, EBAA member banks have restored sight ...

269

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.  Created: 10/12/2010 by National Center for Immunization and Respiratory Diseases (NCIRD).   Date Released: 10/13/2010.

2010-10-12

270

Gaze estimation for off-angle iris recognition based on the biometric eye model  

Science.gov (United States)

Iris recognition is among the highest accuracy biometrics. However, its accuracy relies on controlled high quality capture data and is negatively affected by several factors such as angle, occlusion, and dilation. Non-ideal iris recognition is a new research focus in biometrics. In this paper, we present a gaze estimation method designed for use in an off-angle iris recognition framework based on the ORNL biometric eye model. Gaze estimation is an important prerequisite step to correct an off-angle iris images. To achieve the accurate frontal reconstruction of an off-angle iris image, we first need to estimate the eye gaze direction from elliptical features of an iris image. Typically additional information such as well-controlled light sources, head mounted equipment, and multiple cameras are not available. Our approach utilizes only the iris and pupil boundary segmentation allowing it to be applicable to all iris capture hardware. We compare the boundaries with a look-up-table generated by using our biologically inspired biometric eye model and find the closest feature point in the look-up-table to estimate the gaze. Based on the results from real images, the proposed method shows effectiveness in gaze estimation accuracy for our biometric eye model with an average error of approximately 3.5 degrees over a 50 degree range.

Karakaya, Mahmut; Barstow, Del; Santos-Villalobos, Hector; Thompson, Joseph; Bolme, David; Boehnen, Christopher

2013-05-01

271

Gaze Estimation for Off-Angle Iris Recognition Based on the Biometric Eye Model  

Energy Technology Data Exchange (ETDEWEB)

Iris recognition is among the highest accuracy biometrics. However, its accuracy relies on controlled high quality capture data and is negatively affected by several factors such as angle, occlusion, and dilation. Non-ideal iris recognition is a new research focus in biometrics. In this paper, we present a gaze estimation method designed for use in an off-angle iris recognition framework based on the ANONYMIZED biometric eye model. Gaze estimation is an important prerequisite step to correct an off-angle iris images. To achieve the accurate frontal reconstruction of an off-angle iris image, we first need to estimate the eye gaze direction from elliptical features of an iris image. Typically additional information such as well-controlled light sources, head mounted equipment, and multiple cameras are not available. Our approach utilizes only the iris and pupil boundary segmentation allowing it to be applicable to all iris capture hardware. We compare the boundaries with a look-up-table generated by using our biologically inspired biometric eye model and find the closest feature point in the look-up-table to estimate the gaze. Based on the results from real images, the proposed method shows effectiveness in gaze estimation accuracy for our biometric eye model with an average error of approximately 3.5 degrees over a 50 degree range.

Karakaya, Mahmut [ORNL; Barstow, Del R [ORNL; Santos-Villalobos, Hector J [ORNL; Thompson, Joseph W [ORNL; Bolme, David S [ORNL; Boehnen, Chris Bensing [ORNL

2013-01-01

272

45 Mbps cat's eye modulating retro-reflector link over 7 Km  

Science.gov (United States)

Modulating retro-reflectors (MRR) allow free space optical links with no need for pointing, tracking or a laser on one end of the link. They work by coupling a passive optical retro-reflector with an optical modulator. The most common kind of MRR uses a corner cube retro-reflector. These devices must have a modulator whose active area is as large as the area of the corner cube. This limits the ability to close longer range high speed links because the large aperture need to return sufficient light implies a large modulator capacitance. To overcome this limitation we developed the concept of a cat's eye MRR. Cat's eye MRRs place the modulator in the focal plane of a lens system designed to passively retro-reflect light. Because the light focuses onto the modulator, a small, low capacitance, modulator can be used with a large optical aperture. However, the position of the focal spot varies with the angle of incidence so an array of modulators must be placed in the focal plane, In addition, to avoid having to drive all the modulator pixels, an angle of arrival sensor must be used. We discuss several cat's eye MRR systems with near diffraction limited performance and bandwidths of 45 Mbps. We also discuss a link to a cat's eye MRR over a 7 Km range.

Rabinovich, W. S.; Mahon, R.; Goetz, P. G.; Swingen, L.; Murphy, J.; Ferraro, M.; Burris, R.; Suite, M.; Moore, C. I.; Gilbreath, G. C.; Binari, S.

2006-09-01

273

Shushkakshipaka (dry eye syndrome): A case study  

Digital Repository Infrastructure Vision for European Research (DRIVER)

Ashru-tear secretion is an integral component of the ocular surface physiology; when compromised (quantitatively or qualitatively) lead to shushkakshipaka (dry eye syndrome) with various ocular discomfort symptoms and ultimately the patient may land in corneal blindness.Local, systemic and environmental factors play a major role in its pathogenisis. Vata& Pitta/Rakta vitiation as per Ayurvedic view point are the major contributing pathological factors in its manifestation. Contrary to the ava...

Dhiman, K. S.

2011-01-01

274

Are 3-D Movies Bad for Your Eyes?  

Medline Plus

Full Text Available ... D Movies Bad for Your Eyes? Tweet Eye Health Lifestyle Topics Preventing Eye Injuries Healthy Eyes During ... Eye Protection Eyesight Risks for Smokers Veterans & Eye Health More Lifestyle Topics > EyeSmart Tips Smoking and AMD ...

275

Are 3-D Movies Bad for Your Eyes?  

Medline Plus

Full Text Available ... Problems Medical Marijuana for Glaucoma Pregnancy Preventing Eye Injuries Smokers Sports Teenagers Using Eye Makeup Veterans What ... Eyes? Tweet Eye Health Lifestyle Topics Preventing Eye Injuries Healthy Eyes During Pregnancy Computer Usage & Eye Strain ...

276

Are 3-D Movies Bad for Your Eyes?  

Medline Plus

Full Text Available ... D Movies Bad for Your Eyes? Tweet Eye Health Lifestyle Topics Preventing Eye Injuries Healthy Eyes During ... Eye Protection Eyesight Risks for Smokers Veterans & Eye Health More Lifestyle Topics > EyeSmart Tips Preserve Your Child's ...

277

Enhancing eye donation rates. Training students to be motivators  

Directory of Open Access Journals (Sweden)

Full Text Available Purpose: Medical professionals could enhance eye donation rates by reminding relatives during grief counseling at the time of patient?s death. This study was designed to assess the knowledge and attitudes of final year medical students (future doctors towards eye donation, prior to instruction in eye banking. Methods: The responses of 49 final-year medical students to a questionnaire on eye donation were compared with 24 non-medical students (controls. The results were analysed statistically using the chi-square test. Results: More than one-third of students and controls were unaware that eyes are removed within six hours of death. Eight (16.3% students and 6 (25.0% controls felt that a close relative?s eyes could be donated after death only if he had indicated willingness (P=0.05. Three (6.1% students and 3 (12.5% controls were undecided about donating their own eyes. Nineteen (38.8% students and 6 (25% controls did not know where to go in order to pledge/donate eyes. The controls had poorer knowledge of ocular and systemic contraindications, and they did not know that storage could be prolonged (PConclusions: Controls were poorly informed about various aspects of eye donation suggesting inadequate dissemination of information by the media. Students and controls alike had misconceptions regarding donation of relatives? eyes and hesitation regarding their own. These aspects should be emphasized during undergraduate teaching to dispel misgivings regarding wastage of donor eyes and to encourage future doctors to promote eye donation.

Dhaliwal Upreet

2002-01-01

278

A nanoparticle formulation reduces the corneal toxicity of indomethacin eye drops and enhances its corneal permeability.  

Science.gov (United States)

Indomethacin (IMC) has been shown to reduce post-operative inflammation and to decrease intraocular irritation after cataract extraction and in cystoid macular edema; however, the clinical use of its most commonly used eye drops is limited due to topical side-effects that include burning sensation, irritation and epithelial keratitis. It is known that decreasing direct cell stimulation and reducing the amount applied via increasing bioavailability are useful for improving these issues. In this study, we designed ophthalmic formulations containing 0.5% IMC nanoparticles using zirconia beads and Bead Smash 12 (IMCnano eye drops; particle size 76±59nm, mean±S.D.), and investigated the corneal toxicity of these IMCnano eye drops. IMCnano eye drops are tolerated better by a human cornea epithelial cell line (HCE-T) than commercially available NDSAIDs preparations (IMC, pranoprofen, diclofenac, bromfenac and nepafenac eye drops), and corneal wound healing in rat eyes with debrided corneal epithelium instilled with IMCnano eye drops is significantly better than that of eyes instilled with commercially available IMC eye drops. In addition, the accumulation of IMC in HCE-T cells treated with the IMCnano eye drops for 30min was 19.9% that of the accumulation from commercially available IMC eye drops. On the other hand, the corneal penetration of IMC from IMCnano eye drops was significantly greater than in the case of the commercially available IMC eye drops in both in vivo and in vitro studies using rabbit corneas. Taken together, we hypothesize that a nanoparticle formulation reduces the corneal toxicity of IMC eye drops, probably because the accumulation of IMC from IMCnano eye drops in the eye is lower than that from commercially available IMC eye drops. In addition, the nanoparticle formulation may allow a decrease in the amount of IMC used due to the increase in bioavailability, resulting in reduced drug toxicity. These findings provide significant information that can be used to design further studies aimed at developing less toxic eye drops. PMID:24598350

Nagai, Noriaki; Ito, Yoshimasa; Okamoto, Norio; Shimomura, Yoshikazu

2014-05-01

279

Antioxidants and Age-Related Eye Disease  

Science.gov (United States)

... Your Vision > Nutrition > Antioxidants & Age-Related Eye Disease Antioxidants & Age-Related Eye Disease Cataracts and age-related ... of protecting the eyes from these diseases. Research - Antioxidants and AMD The Age-Related Eye Disease Study ...

280

Problems associated with the use of beryllium in a fusion ceramic blanket. A designer point of view  

International Nuclear Information System (INIS)

Compatibility problems of beryllium with various structural and ceramic breeder materials are being investigated in Europe, both in-pile and out-of-pile. There are, however, three other problems which needs more work: 1. Beryllium swells under neutron irradiation. Extrapolation of experimental data indicates that at a fluence of 3 MWa/m2, foreseen for ITER, and a temperature of 500deg C the swelling is about 4.5%, while for the Demo-reactor (5 MWa/m2 and 600deg C) the swelling could be in excess of 12%. 2. Beryllium becomes very brittle under irradiation. Experimental data show that elongation is reduced practically to zero for temperatures up to 600deg C after a relatively low neutron fluence (1.5 x 1021 cm-2, E > 1 MeV). 3. Recent tritium release experiments from beryllium irradiated at 5 x 1022 n/cm2 (E > 1 MeV) and 75deg C (Baldwin et al.) show that, below 600deg C, a small amount of tritium (? 2%) is released by a process controlled by temperature dependent trapping and diffusivity. The rest (98%) is release for temperatures slightly above 600deg C, whereby this release seems to be connected with the formation of helium bubbles. This phenomenon is probably connected with beryllium swelling as well. The first two points make a design with beryllium very difficult, the third may have not so good safety implications. The data mentioned above refer to beryllium fabricated 25-35 years ago. Futhermore, most irradiations at high fluences have been performed a low temperatures (< 100deg C). This of course is not the case for the blanket application, where beryllium is typically irradiated in the temperature range 250 ./. 600deg C. New fabrication methods are available today, where a more isotropic material is manufactured. This, together with the reduction of the oxygen content, may improve the situation quite considerably. There are already indications that this new kinds of beryllium are less brittle when irradiated at high temperatures. (orig./KP)

1991-08-01

 
 
 
 
281

Computer-Assisted Eye Examination: Background and Prospects.  

Science.gov (United States)

REport describes the research and development that resulted in the frist clinically tested computerized subjective refractor. In addition to engineering descriptions and flow charts the report includes background history of eye-refractor design and other ...

E. Marg

1982-01-01

282

Eye movement abnormalities.  

Science.gov (United States)

Generation and control of eye movements requires the participation of the cortex, basal ganglia, cerebellum and brainstem. The signals of this complex neural network finally converge on the ocular motoneurons of the brainstem. Infarct or hemorrhage at any level of the oculomotor system (though more frequent in the brain-stem) may give rise to a broad spectrum of eye movement abnormalities (EMAs). Consequently, neurologists and particularly stroke neurologists are routinely confronted with EMAs, some of which may be overlooked in the acute stroke setting and others that, when recognized, may have a high localizing value. The most complex EMAs are due to midbrain stroke. Horizontal gaze disorders, some of them manifesting unusual patterns, may occur in pontine stroke. Distinct varieties of nystagmus occur in cerebellar and medullary stroke. This review summarizes the most representative EMAs from the supratentorial level to the brainstem. PMID:22377853

Moncayo, Jorge; Bogousslavsky, Julien

2012-01-01

283

Eye preferences in captive chimpanzees.  

Science.gov (United States)

Over the last century, the issue of brain lateralization in primates has been extensively investigated and debated, yet no previous study has reported eye preference in great apes. This study examined eye preference in 45 captive chimpanzees (Pan troglodytes) in response to various stimuli. Eye preference was assessed when animals looked through a hole that only accommodated one eye at an empty box, a mirror, a picture of a dog, a rubber snake, food biscuits, bananas, a rubber duck, and a video camera. Main effects of stimulus type were found for direction of eye preference, number of looks, and looking duration, but not for strength of eye preference. A left-eye bias was found for viewing the rubber snake and a right-eye bias was found for viewing the bananas, supporting theories that emotional valence may affect lateralized behaviors. In addition, a significant shift in eye preference took place from the initial look to subsequent looks when viewing the snake. These results are not consistent with previous reports of human eye preference and may reflect lateralization differences for emotional processing. No relationship between eye preference and previously recorded hand preference was found. PMID:22733385

Braccini, Stephanie N; Lambeth, Susan P; Schapiro, Steven J; Fitch, W Tecumseh

2012-09-01

284

Equivalence is in the Eye of the Beholder  

CERN Multimedia

In a recent provocative paper, Lamport points out "the insubstantiality of processes" by proving the equivalence of two different decompositions of the same intuitive algorithm by means of temporal formulas. We point out that the correct equivalence of algorithms is itself in the eye of the beholder. We discuss a number of related issues and, in particular, whether algorithms can be proved equivalent directly.

Gurevich, Yu G; Gurevich, Yuri; Huggins, James K.

1997-01-01

285

Incorporation of intraocular scattering in schematic eye models  

Energy Technology Data Exchange (ETDEWEB)

Beckmann's theory of scattering from rough surfaces is applied to obtain, from the experimental veiling glare functions, a diffuser that when placed at the pupil plane would produce the same scattering halo as the ocular media. This equivalent diffuser is introduced in a schematic eye model, and its influence on the point-spread function and the modulation-transfer function of the eye is analyzed.

Navarro, R.

1985-11-01

286

Incorporation of intraocular scattering in schematic eye models  

International Nuclear Information System (INIS)

Beckmann's theory of scattering from rough surfaces is applied to obtain, from the experimental veiling glare functions, a diffuser that when placed at the pupil plane would produce the same scattering halo as the ocular media. This equivalent diffuser is introduced in a schematic eye model, and its influence on the point-spread function and the modulation-transfer function of the eye is analyzed

1985-01-01

287

Improving eye care in the primary health care setting  

Digital Repository Infrastructure Vision for European Research (DRIVER)

One of the challenges facing primary health care in South Africa is the delivery of quality eye care to all South Africans. In this regard the role of the primary health care worker, as the first point of contact, is crucial. This paper reports on the problems primary health care workers experience in providing quality eye care in Region B of the Free State. Problems identified by those involved in the study include the cumbersome referral system, the unavailability of appropriate medicine at...

Wet, M.; Ackermann, L.

2000-01-01

288

Genetic analyses of the human eye colours using a novel objective method for eye colour classification  

DEFF Research Database (Denmark)

In this study, we present a new objective method for measuring the eye colour on a continuous scale that allows researchers to associate genetic markers with different shades of eye colour. With the use of the custom designed software Digital Iris Analysis Tool (DIAT), the iris was automatically identified and extracted from high resolution digital images. DIAT was made user friendly with a graphical user interface. The software counted the number of blue and brown pixels in the iris image and calculated a Pixel Index of the Eye (PIE-score) that described the eye colour quantitatively. The PIE-score ranged from â??1 to 1 (brown to blue). The software eliminated the need for user based interpretation and qualitative eye colour categories. In 94% (570) of 605 analyzed eye images, the iris region was successfully extracted and a PIE-score was calculated. A very high correlation between the PIE-score and the human perception of eye colour was observed. The correlations between the PIE-scores and the six IrisPlexSNPs (HERC2 rs12913832, OCA2 rs1800407, SLC24A4 rs12896399, TYR rs1393350, SLC45A2 rs16891982 and IRF4 rs12203592) were analyzed in 570 individuals. Significant differences (p < 10â??6) in the PIE-scores of the individuals typed as HERC2 rs12913832 G (PIE = 0.99) and rs12913832 GA (PIE = â??0.71) or A (PIE = â??0.87) were observed. We adjusted for the effect of HERC2 rs12913832 and showed that the quantitative PIE-scores were significantly associated with SNPs with minor effects (OCA2 rs1800407, SLC24A4 rs12896399 and TYR rs1393350) on the eye colour. We evaluated the two published prediction models for eye colour (IrisPlex [1] and Snipper[2]) and compared the predictions with the PIE-scores. We found good concordance with the prediction from individuals typed as HERC2 rs12913832 G. However, both methods had difficulties in categorizing individuals typed as HERC2 rs12913832 GA because of the large variation in eye colour in HERC2 rs12913832 GA individuals. With the use of the DIAT software and the PIE-score, it will be possible to automatically compare the iris colour of large numbers of iris images obtained by different studies and to perform large meta-studies that may reveal loci with small effects on the eye colour.

Andersen, Jeppe D.; Johansen, Peter

2013-01-01

289

Comparison of Dry Eye and Corneal Sensitivity between Small Incision Lenticule Extraction and Femtosecond LASIK for Myopia  

Science.gov (United States)

Purpose To investigate the changes in dry eye symptoms and clinical signs and corneal sensitivity after small incision lenticule extraction (SMILE) and femtosecond LASIK (femto-LASIK). Design Prospective, non-randomized comparative study. Methods The study included a total of 71 eyes of 71 patients; the SMILE group comprised 38 eyes of 38 patients, and the femto-LASIK group comprised 33 eyes of 33 patients. Ocular Surface Disease Index (OSDI), Tear film breakup time (TBUT), the Schirmer test without anesthesia (S1T), corneal fluorescein staining, and central corneal sensation were evaluated before surgery and at 1 week, 1 month, 3 months, and 6 months after surgery. Results OSDI scores in both groups were increased immediately and returned to preoperative level at 1 month after surgeries. The TBUT values in both groups were reduced after surgeries relative to their preoperative scores. Patients in SMILE group were less likely to have corneal staining compared with those in the femto-LASIK group ([odds ratio] OR?=?0.50, 95% [confidence interval] CI 0.28 to 0.93, P?=?0.03). Central corneal sensitivity was decreased at all postoperative time points in both groups. However, the central corneal sensation scores in the SMILE group were greater than that in the femto-LASIK group at all of the postoperative time points (all PLASIK in lower risk of postoperative corneal staining and less reduction of corneal sensation.

Li, Meiyan; Zhao, Jing; Shen, Yang; Li, Tao; He, Li; Xu, Hailin; Yu, Yongfu; Zhou, Xingtao

2013-01-01

290

ECEM (Eye Closure, Eye Movements): application to depersonalization disorder.  

Science.gov (United States)

Eye Closure, Eye Movements (ECEM) is a hypnotically-based approach to treatment that incorporates eye movements adapted from the Eye Movement Desensitization and Reprocessing (EMDR) protocol in conjunction with hypnosis for the treatment of depersonalization disorder. Depersonalization Disorder has been differentiated from post-traumatic stress disorders and has recently been conceptualized as a subtype of panic disorder (Baker et al., 2003; David, Phillips, Medford, & Sierra, 2004; Segui et. al., 2000). During ECEM, while remaining in a hypnotic state, clients self-generated six to seven trials of eye movements to reduce anticipatory anxiety associated with depersonalization disorder. Eye movements were also used to process triggers that elicited breath holding, often followed by episodes of depersonalization. Hypnotic suggestions were used to reverse core symptoms of depersonalization, subjectively described as "feeling unreal" (Simeon et al., 1997). PMID:19862896

Harriet, E Hollander

2009-10-01

291

Eye movement; Experimental and clinical study using cine mode MRI  

Energy Technology Data Exchange (ETDEWEB)

This is a special lecture at the 96th Annual Congress of the Japanese Ophthalmological Society in 1992, presenting studies on eye movement using magnetic resonance imaging (MRI). Using cine mode MRI technology, two methods for producing a series of photographs have been invented: (1) the moving eye method or dynamic method in which the subjects were asked to perform 256 or 512 vertical and horizontal eye movements in synchronization with a sound trigger; and (2) the fixed eye method or static method in which the subjects were asked to gaze at individual points in a 5 to 7 point sequence as indicated by the investigator. MRI data was generated and the resulting series of photographs were observed in cine mode on a televisin monitor. Displaying the MRI-generated photographs in cine mode enables direct observation of eye movement, optic nerve and extraocular muscles within the orbit. Although the moving eye method is more accurate in its portrayal of the actual eye movement, at least 256 eye movements are required for about 5 minutes, causing physical and mental load for the subjects. The fixed eye method was thus used to examine ophthalmoplegia, including abducens palsy, oculomotor palsy, fracture of the orbital wall, foreign bodies in the orbit, Duane's syndrome, endocrine myopathy, esotropia and exotropia. This allowed the investigation of anatomical changes, such as atrophy or hypertrophy, and the functional state caused by contraction and relaxation of the extraocular muscles. Transposition of the extraocular muscles for paralytic squint was reexamined and a new surgical procedure was developed for abducens palsy. The measurement of the length, thickness and weight of the extraocular muscles from the MRI-generated photographs allowed more accurate analysis. Three dimensional reconstructive method of MRI provided a valuable tool for evaluating the orbit. (N.K.) 67 refs.

Inatomi, Akihiro (Shiga University of Medical Science, Otsu (Japan)); Kaji, Kazutaka; Sasaki, Kenji (and others)

1992-12-01

292

Does eye tremor provide the hyperacuity phenomenon?  

International Nuclear Information System (INIS)

This paper is devoted to a study of the role of the fluctuations that the eye is subject to, from the point of view of noise-enhanced processing. To this end, a basic model of the retina is considered, namely a regular sampler subject to space and time fluctuations that model the random sampling and the involuntary eye tremor respectively. The filtering that can be done by the photoreceptor is also taken into account and the study focuses on a stochastic model of a natural scene. To quantify the effect of the noise, a coefficient of correlation between the signal acquired by a given photoreceptor and a given point of the scene that the eye is looking at is considered. It is shown both for academic examples and for a more realistic case that the fluctuations which affect the retina can induce noise-enhanced processing effects. The observed effect is then interpreted as a stochastic control of the retina via the random tremor

2009-01-01

293

Eye Gaze Tracking using Correlation Filters  

Energy Technology Data Exchange (ETDEWEB)

In this paper, we studied a method for eye gaze tracking that provide gaze estimation from a standard webcam with a zoom lens and reduce the setup and calibration requirements for new users. Specifically, we have developed a gaze estimation method based on the relative locations of points on the top of the eyelid and eye corners. Gaze estimation method in this paper is based on the distances between top point of the eyelid and eye corner detected by the correlation filters. Advanced correlation filters were found to provide facial landmark detections that are accurate enough to determine the subjects gaze direction up to angle of approximately 4-5 degrees although calibration errors often produce a larger overall shift in the estimates. This is approximately a circle of diameter 2 inches for a screen that is arm s length from the subject. At this accuracy it is possible to figure out what regions of text or images the subject is looking but it falls short of being able to determine which word the subject has looked at.

Karakaya, Mahmut [ORNL; Boehnen, Chris Bensing [ORNL; Bolme, David S [ORNL; Mahallesi, Mevlana [Meliksah University, Turkey; Kayseri, Talas [Meliksah University, Turkey

2014-01-01

294

Gradient Index (GRIN) Lens Multimode Fiber Probe for Laser Induced Breakdown in the Eye. (Reannouncement with New Availability Information).  

Science.gov (United States)

A model laser surgical probe was designed and built to employ laser induced breakdown (LIB) in cutting fibrovascular membranes within the vitreous cavity of the eye. Current surgical techniques for removing such membranes from eyes with severe proliferati...

C. A. Toth D. X. Hammer K. Slawinski

1994-01-01

295

A push-pull treatment for strengthening the 'lazy eye' in amblyopia.  

Science.gov (United States)

Almost all individuals exhibit sensory eye dominance, one neural basis of which is unequal interocular inhibition. Sensory eye dominance can impair binocular functions that depend on both excitatory and inhibitory mechanisms. We developed a 'push-pull' perceptual learning protocol that simultaneously affects the excitatory and inhibitory networks to reduce sensory eye dominance and improve stereopsis in adults with otherwise normal vision. The push-pull protocol provides a promising clinical paradigm for treating the extreme sensory eye dominance in amblyopia ('lazy eye'). The prevailing standard of care does not directly treat sensory eye dominance; instead, selected excitatory functions in the amblyopic eye are stimulated while the strong eye is patched, on the assumption that recovery of the weak eye's excitatory functions rebalances the eyes. Patching the strong eye does not directly address interocular inhibition; in contrast, the push-pull protocol by design excites the weak eye, while completely inhibiting the strong eye's perception to recalibrate the interocular balance of excitatory and inhibitory interactions. Here, we show that three adult amblyopes who trained on the push-pull protocol gained longstanding improvements in interocular balance and stereopsis. Our findings provide a proof-of-concept and evidence that push-pull learning leads to long-term plasticity. PMID:23618663

Ooi, Teng Leng; Su, Yong R; Natale, Danielle M; He, Zijiang J

2013-04-22

296

Modular DIPS, 2.5-kWe modules for lunar/Mars surface applications, design point selection summary  

International Nuclear Information System (INIS)

This paper reports that the Dynamic Isotope Power System (DIPS) Demonstration Program is currently focused on the development of a standardized 2.5-kWe portable generator for multiple applications on the lunar or Martian surface. An optimum system configuration has been developed for the 2.5-kWe DIPS module that provides a system with a radiator area which is small and manageable without significantly impacting the system mass, efficiency, and technological risk. The 2.5-kWe DIPS module configuration was developed based on a systematic series of studies. Initially, technology breakpoints in the DIPS component and subsystem designs were identified. Based on the technology assessments, the maximum design temperature for the system was selected and various system and subsystem configurations were evaluated. Finally, the subsystem and system designs for the selected configuration were optimized using a detailed system design optimization computer code

1992-08-03

297

The software design of multi-branch, multi-point remote monitoring system for temperature measurement based on MSP430 and DS18B20  

International Nuclear Information System (INIS)

This paper present that the system can acquire the remote temperature measurement data of 40 monitoring points, through the RS-232 serial port and the Intranet. System's hardware is consist of TI's MSP430F149 mixed-signal processor and UA7000A network module. Using digital temperature sensor DS18B20, the structure is simple and easy to expand, the sensors directly send out the temperature data, MSP430F149 has the advantage of ultra-low-power and high degree of integration. Using msp430F149, the multi-branch multi-point temperature measurement system is powerful, simple structure, high reliability, strong anti-interference capability. The client software is user-friendly and easy to use, it is designed in Microsoft Visual C+ +6.0 environment. The monitoring system is able to complete a total of 4 branches of the 40-point temperature measurements in real-time remote monitoring. (authors)

2009-01-01

298

New eye phantom for ophthalmic surgery.  

Science.gov (United States)

ABSTRACT. In this work, we designed and realized a new phantom able to mimic the principal mechanical, rheological, and physical cues of the human eye and that can be used as a common benchmark to validate new surgical procedures, innovative vitrectomes, and as a training system for surgeons. This phantom, in particular its synthetic humor vitreous, had the aim of reproducing diffusion properties of the natural eye and can be used as a system to evaluate the pharmacokinetics of drugs and optimization of their dose, limiting animal experiments. The eye phantom was built layer-by-layer starting from the sclera up to the retina, using low cost and easy to process polymers. The validation of the phantom was carried out by mechanical characterization of each layer, by diffusion test with commercial drugs into a purposely developed apparatus, and finally by a team of ophthalmic surgeons. Experiments demonstrated that polycaprolactone, polydimethylsiloxane, and gelatin, properly prepared, are the best materials to mimic the mechanical properties of sclera, choroid, and retina, respectively. A polyvinyl alcohol-gelatin polymeric system is the best for mimicking the viscosity of the human humor vitreous, even if the bevacizumab half-life is lower than in the human eye. PMID:24887746

Fogli, Gessica; Orsi, Gianni; De Maria, Carmelo; Montemurro, Francesca; Palla, Michele; Rizzo, Stanislao; Vozzi, Giovanni

2014-06-01

299

Assessing and managing eye injuries  

Digital Repository Infrastructure Vision for European Research (DRIVER)

njuries to the eye are common. Many are minor but, if not treated quickly and appropriately, can lead to sight-threatening complications. Other injuries are severe, and even with expert management sight can be lost. Prevention of blindness from eye injuries requires: * injury prevention (health promotion including advocacy) * early presentation by the patient (health promotion and health worker training) * accurate assessment (good primary eye care and first aid) * prompt refe...

Karin Lecuona

2005-01-01

300

Look beyond the red eyes!  

Science.gov (United States)

This is a case of a 63-year-old gentleman who presented with persistent red eyes to the eye clinic for several months. He had been seen in the eye department on several visits when he was noted to have red ears too. This led to further review in the rheumatology and ear, nose and throat clinic to confirm the diagnosis of relapsing polychondritis. He was treated successfully with systemic steroids.

Kumar, Anupma

2011-01-01

 
 
 
 
301

Assessing and managing eye injuries  

Directory of Open Access Journals (Sweden)

Full Text Available njuries to the eye are common. Many are minor but, if not treated quickly and appropriately, can lead to sight-threatening complications. Other injuries are severe, and even with expert management sight can be lost. Prevention of blindness from eye injuries requires: * injury prevention (health promotion including advocacy * early presentation by the patient (health promotion and health worker training * accurate assessment (good primary eye care and first aid * prompt referral of serious injuries requiring specialist management.

Karin Lecuona

2005-10-01

302

Aging and dry eye disease  

Digital Repository Infrastructure Vision for European Research (DRIVER)

Dry eye disease is a prevalent eye disorder that in particular affects the elderly population. One of the major causes of dry eye, meibomian gland dysfunction (MGD), shows increased prevalence with aging. MGD is caused by hyperkeratinization of the ductal epithelium of meibomian gland and reduced quantity and/or quality of meibum, the holocrine product that stabilizes and prevents the evaporation of the tear film. Of note, retinoids which are used in current anti-aging cosmetics may promote t...

Ding, Juan; Sullivan, David A.

2012-01-01

303

Eye dialect: translating the untranslatable  

Digital Repository Infrastructure Vision for European Research (DRIVER)

The term ‘eye dialect’ was first coined in 1925 by George P. Krapp in The English Language in America (McArthur 1998). The term was used to describe the phenomenon of unconventional spelling used to reproduce colloquial usage. When one encounters such spellings “the convention violated is one of the eyes, and not of the ear”. Furthermore, eye dialect would be used by writers “not to indicate a genuine difference in pronunciation, but the spelling is a friend...

Brett, David Finbar

2009-01-01

304

The eye and the heart  

Digital Repository Infrastructure Vision for European Research (DRIVER)

The vasculature of the eye and the heart share several common characteristics. The easily accessible vessels of the eye are therefore-to some extent-a window to the heart. There is interplay between cardiovascular functions and risk factors and the occurrence and progression of many eye diseases. In particular, arteriovenous nipping, narrowing of retinal arteries, and the dilatation of retinal veins are important signs of increased cardiovascular risk. The pressure in the dilated veins is oft...

2013-01-01

305

The eye and the heart  

Digital Repository Infrastructure Vision for European Research (DRIVER)

The vasculature of the eye and the heart share several common characteristics. The easily accessible vessels of the eye are therefore—to some extent—a window to the heart. There is interplay between cardiovascular functions and risk factors and the occurrence and progression of many eye diseases. In particular, arteriovenous nipping, narrowing of retinal arteries, and the dilatation of retinal veins are important signs of increased cardiovascular risk. The pressure in the dilated veins is...

2013-01-01

306

Can the Hazard Assessment and Critical Control Points (HACCP) system be used to design process-based hygiene concepts?  

Digital Repository Infrastructure Vision for European Research (DRIVER)

Recently, the HACCP (Hazard Analysis and Critical Control Points) concept was proposed as possible way to implement process-based hygiene concepts in clinical practice, but the extent to which this food safety concept can be transferred into the health care setting is unclear. We therefore discuss possible ways for a translation of the principles of the HACCP for health care settings. While a direct implementation of food processing concepts into health care is not very likely to be feasible ...

Hu?bner, N. -o; Fleßa, S.; Haak, J.; Wilke, F.; Hu?bner, C.; Dahms, C.; Hoffmann, W.; Kramer, A.

2011-01-01

307

Eye Surgery Light  

Science.gov (United States)

During eye surgery, the surgeon uses an illuminating instrument called an opthalmoscope for close examination of the retina or the interior of the eye. Ordinarily, electric power for the head-mounted light is supplied through a cord from an overhead swivel arm or a floor pedestal. Within limits of cord length and swivel arm movement, the surgeon has considerable freedom of motion. But when more than one opthalmoscope is involved, tangling and interference of the power cords becomes a problem. St. Luke's Hospital, Cleveland, Ohio asked Lewis Research Center for assistance in finding a solution. Lewis responded with a battery-powered system that totally frees the surgeon of attached cords and swivels. Borrowing from space technology, Lewis used small, lightweight nickel-cadmium batteries that can deliver high intensity light for an hour and can be recharged overnight. The Opthalmoscope Powerpack consists of eight batteries in three containers affixed to a webbed belt, and a novel on-off switch equipped with a springloaded plexiglass "flapper." The belt pack is worn underneath the surgical gown and the flapper permits the doctor to activate the switch by elbow pressure. Lewis built five units and they have been in service at St. Luke's Hospital for a year. Used for routine examinations as well as for surgery, they have demonstrated excellent reliability.

1978-01-01

308

Technical evaluation of the electrical, instrumentation, and control design aspects of the low temperature overpressure protection system for the Point Beach Nuclear Power Plant, Units 1 and 2  

International Nuclear Information System (INIS)

The technical evaluation is presented for the electrical, instrumentation, and control design aspects of the low temperature overpressure protection system for the Point Beach nuclear power plant, Units 1 and 2. Design basis criteria used to evaluate the acceptability of the system included operator action, system testability, single failure criterion, and seismic Category I and IEEE Std-279-1971 criteria. This report is supplied as part of the Selected Electrical, Instrumentation, and Control Systems Issues Support Program being conducted for the U.S. Nuclear Regulatory Commission by Lawrence Livermore Laboratory

1979-01-01

309

Human eye modelling for ophthalmic simulators project for clinic applications  

International Nuclear Information System (INIS)

Most of eye tumors are treated by surgical means, which involves the enucleation of affected eyes. In terms of treatment and control of diseases, there is brachytherapy, which often utilizes small applicator of Co-60, I-125, Ru-106, Ir-192, etc. These methods are shown to be very efficient but highly cost. The objective of this work is propose a detailed simulator modelling for eye characterization. Additionally, this study can contribute to design and build a new applicator in order to reduce the cost and to allow more patients to be treated

2002-08-11

310

Are 3-D Movies Bad for Your Eyes?  

Medline Plus

Full Text Available ... Bad for Your Eyes? Tweet Eye Health Lifestyle Topics Preventing Eye Injuries Healthy Eyes During Pregnancy Computer ... Risks for Smokers Veterans & Eye Health More Lifestyle Topics > EyeSmart Tips "No Rub" a No Go To ...

311

Are 3-D Movies Bad for Your Eyes?  

Medline Plus

Full Text Available ... for Simple Eye Problems Medical Marijuana for Glaucoma Pregnancy Preventing Eye Injuries Smokers Sports Teenagers Using Eye ... Lifestyle Topics Preventing Eye Injuries Healthy Eyes During Pregnancy Computer Usage & Eye Strain Maintaining Your Sight with ...

312

Are 3-D Movies Bad for Your Eyes?  

Medline Plus

Full Text Available ... Movies Bad for Your Eyes? Tweet Eye Health Lifestyle Topics Preventing Eye Injuries Healthy Eyes During Pregnancy ... Eyesight Risks for Smokers Veterans & Eye Health More Lifestyle Topics > EyeSmart Tips "No Rub" a No Go ...

313

A self-calibrating, camera-based eye tracker for the recording of rodent eye movements  

Directory of Open Access Journals (Sweden)

Full Text Available Much of neurophysiology and vision science relies on careful measurement of a human or animal subject’s gaze direction. Video-based eye trackers have emerged as an especially popular option for gaze tracking, because they are easy to use and are completely non-invasive. However, video eye trackers typically require a calibration procedure in which the subject must look at a series of points at known gaze angles. While it is possible to rely on innate orienting behaviors for calibration in some nonhuman species, other species, such as rodents, do not reliably saccade to visual targets, making this form of calibration impossible. To overcome this problem, we developed a fully-automated infrared video eye-tracking system that is able to quickly and accurately calibrate itself without requiring cooperation from the subject. This technique relies on the optical geometry of the cornea and uses computer controlled motorized stages to rapidly estimate the geometry of the eye relative to the camera. The accuracy and precision of our system was carefully measured using an artificial eye, and its capability to monitor the gaze of rodents was verified by tracking spontaneous saccades and evoked oculomotor reflexes in head-fixed rats (in both cases, we obtained measurements that are consistent with those found in the literature. Overall, given its fully-automated nature and its intrinsic robustness against operator errors, we believe that our eye-tracking system enhances the utility of existing approaches to gaze-tracking in rodents and represents a valid tool for rodent vision studies.

DavideZoccolan

2010-11-01

314

[Priority trends in the sphere of eye injuries].  

Science.gov (United States)

Comprehensive recent research of eye traumatism is described, aspects related with changes in the trauma structure are defined and advanced methods of diagnostics as well as of therapeutic and surgical treatment in eye trauma are elucidated in the paper. It is pointed out that the above study results are valuable for rehabilitation of victims during peacetime, in emergency situations and in calamities; the contribution of civil ophthalmologic institutions to rendering a specialized medical care to victims of military conflicts is equally important. The case study comprises extensive research findings that can be used in the below cases requiring a specialized medical care: penetrating eye injuries, contusion, burn injuries of the eye, splintered trauma etc.; the current micro-surgery standards must be adhered to and the latest technologies must be used. Finally, the important role of and valuable contributions to the above research made by the Calamity Medicine Center ("Zashchita") are underlined. PMID:15017770

Gundorova, R A

2004-01-01

315

Sun, UV Radiation and Your Eyes  

Science.gov (United States)

... Is an Ophthalmologist? Your Eyes & the Sun Eye Health News Consumer Alerts The Sun, UV Radiation and Your Eyes Tweet Keep an ... them good habits for a lifetime of eye health. Next Page: Summer Sun Eye Safety Page updated: Apr. 29, 2014 UV & ...

316

Eye vision system using programmable micro-optics and micro-electronics  

Science.gov (United States)

Proposed is a novel eye vision system that combines the use of advanced micro-optic and microelectronic technologies that includes programmable micro-optic devices, pico-projectors, Radio Frequency (RF) and optical wireless communication and control links, energy harvesting and storage devices and remote wireless energy transfer capabilities. This portable light weight system can measure eye refractive powers, optimize light conditions for the eye under test, conduct color-blindness tests, and implement eye strain relief and eye muscle exercises via time sequenced imaging. Described is the basic design of the proposed system and its first stage system experimental results for vision spherical lens refractive error correction.

Riza, Nabeel A.; Amin, M. Junaid; Riza, Mehdi N.

2014-02-01

317

Trilobite eyes and the optics of Des Cartes and Huygens.  

Science.gov (United States)

The thick lenses in the aggregate eyes of a group of trilobites were double structures designed to eliminate spherical aberration. The shape of the optically correcting interface is in accord with constructions by Des Cartes and Huygens and is dictated by a fundamental law of physics. Trilobites may have evolved such sophisticated eye-lenses to maximise optic neurone response in a dimly lit environment. PMID:1091864

Clarkson, E N; Levi-Setti, R

1975-04-24

318

Gray Eye Traffic Surveillance  

Directory of Open Access Journals (Sweden)

Full Text Available Gray Eye Traffic Surveillance (GETS is a system based on image processing technology and database processing for the purpose of Traffic Surveillance. This system is built specifically for India, where standard fonts and scripts for the number plates are rarely followed and corruption is a menace.This paper attempts to present a system to automate the entire process of traffic surveillance and curb corruption at the same time. A two way approach of developing a desktop and a web based mobile application is proposed. The desktop based application uses image processing technology to recognize the license number from image of vehicles captured by surveillance cameras and maintain a track log. The web based mobile application can be used by authorized traffic police to file complaints. The general public can log into this application to view their log and file complaints in case of any discrepancies. Different database schemas are used for various purpose like authentication, crime details, tracking system.

Ayesha Butalia #1, Durgesh Maru*2, Kuldeep Baheti*3, Avais Mohammad*4, Ankit Bagdiya*5

2011-06-01

319

Dry eye disease after LASIK  

Digital Repository Infrastructure Vision for European Research (DRIVER)

LASIK is a surgical tehnique for the correction of refractive errors (myopia, hyperopia, astygmatism). It results in a reshape of the cornea with ocular surface and especially tear film disease. It is a cause for a iatrogenic dry eye syndrome. Neurogenic and inflamatory theory explain this disease. The main therapy of dry eye is the replacement with artificial tears.

T?uru, L.; Alexandrescu, C.; Stana, D.; Tudosescu, R.

2012-01-01

320

Amblyopia--or lazy eye.  

Science.gov (United States)

An amblyopia, or lazy eye, is an eye that is healthy in all respects but which has defective vision, even after the fitting of correcting lenses for a refractive error. Amblyopia can be a strongly hereditary condition. The author describes the predisposing conditions and discusses methods of assessment and the effectiveness of its present treatment. PMID:7625935

Fraser, H

1995-06-01

 
 
 
 
321

Community Eye Health MSc dissertations  

Directory of Open Access Journals (Sweden)

Full Text Available All MSc students at the International Centre for Eye Health (ICEH carry out a dissertation project as part of the Community Eye Health MSc course. Most of the dissertations are excellent pieces of original and valuable research work, sometimes the first of their kind in their authors’ country or region.

Daksha Patel

2007-03-01

322

Photochemical injury to the foveomacula of the monkey eye following argon blue-green panretinal photocoagulation.  

Digital Repository Infrastructure Vision for European Research (DRIVER)

PURPOSE: Visual loss following panretinal photocoagulation was found in the Diabetic Retinopathy and the Early Treatment Diabetic Retinopathy Studies. This study was designed to test the hypothesis that light scattered in the monkey eye during a procedure designed to mimic a clinical panretinal photocoagulation (PRP) can produce a photochemical injury to the foveomacula. METHODS: Ten eyes of 5 adult cynomologous monkeys underwent a PRP using an argon blue-green laser. Three eyes in 2 monkeys ...

Parver, L. M.

2000-01-01

323

Fluorophotometry as a diagnostic tool for the evaluation of dry eye disease  

Digital Repository Infrastructure Vision for European Research (DRIVER)

Abstract Background Dry eye disease is a common debilitating ocular disease. Current diagnostic tests used in dry eye disease are often neither sensitive nor reproducible, making it difficult to accurately diagnose and determine end points for clinical trials, or evaluate the usefulness of different medications in the treatment of dry eye disease. The recently developed fluorophotometer can objectively detect changes in the corneal epithelium by quantitatively measuring its b...

Fahim Magid M; Haji Shamim; Koonapareddy Chakravarthy V; Fan Vincent C; Asbell Penny A

2006-01-01

324

Oxidative stress and its downstream signaling in aging eyes  

Science.gov (United States)

Background Oxidative stress (OS) and its biomarkers are the biochemical end point of the imbalance between reactive oxygen species (ROS) production and the ability of the antioxidant (AOX) biological systems to fight against oxidative injury. Objective We reviewed the role of OS and its downstream signaling in aging eyes. Methods A search of the literature and current knowledge on the physiological and pathological mechanisms of OS were revisited in relation to the eyes and the aging process. Most prevalent ocular diseases have been analyzed herein in relation to OS and nutraceutic supplements, such as dry-eye disorders, glaucoma, age-related macular degeneration, and diabetic retinopathy. Results Clinical, biochemical, and molecular data from anterior and posterior eye segment diseases point to OS as the common pathogenic mechanism in the majority of these ocular disorders, many of which are pathologies causing visual impairment, blindness, and subsequent loss of life quality. Studies with nutraceutic supplements in aging eye-related pathologies have also been reviewed. Conclusion OS, nutritional status, and nutraceutic supplements have to be considered within the standards of care of older ophthalmologic patients. OS biomarkers and surrogate end points may help in managing the aging population with ocular diseases.

Pinazo-Duran, Maria Dolores; Gallego-Pinazo, Roberto; Garcia-Medina, Jose Javier; Zanon-Moreno, Vicente; Nucci, Carlo; Dolz-Marco, Rosa; Martinez-Castillo, Sebastian; Galbis-Estrada, Carmen; Marco-Ramirez, Carla; Lopez-Galvez, Maria Isabel; Galarreta, David J; Diaz-Llopis, Manuel

2014-01-01

325

Can the Hazard Assessment and Critical Control Points (HACCP system be used to design process-based hygiene concepts?  

Directory of Open Access Journals (Sweden)

Full Text Available Recently, the HACCP (Hazard Analysis and Critical Control Points concept was proposed as possible way to implement process-based hygiene concepts in clinical practice, but the extent to which this food safety concept can be transferred into the health care setting is unclear. We therefore discuss possible ways for a translation of the principles of the HACCP for health care settings. While a direct implementation of food processing concepts into health care is not very likely to be feasible and will probably not readily yield the intended results, the underlying principles of process-orientation, in-process safety control and hazard analysis based counter measures are transferable to clinical settings. In model projects the proposed concepts should be implemented, monitored, and evaluated under real world conditions.

Hübner, N.-O.

2011-01-01

326

Design and Study on Sliding Mode Extremum Seeking Control of the Chaos Embedded Particle Swarm Optimization for Maximum Power Point Tracking in Wind Power Systems  

Directory of Open Access Journals (Sweden)

Full Text Available This paper proposes a sliding mode extremum seeking control (SMESC of chaos embedded particle swarm optimization (CEPSO Algorithm, applied to the design of maximum power point tracking in wind power systems. Its features are that the control parameters in SMESC are optimized by CEPSO, making it unnecessary to change the output power of different wind turbines, the designed in-repetition rate is reduced, and the system control efficiency is increased. The wind power system control is designed by simulation, in comparison with the traditional wind power control method, and the simulated dynamic response obtained by the SMESC algorithm proposed in this paper is better than the traditional hill-climbing search (HCS and extremum seeking control (ESC algorithms in the transient or steady states, validating the advantages and practicability of the method proposed in this paper.

Jui-Ho Chen

2014-03-01

327

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

Science.gov (United States)

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

Smith, Nicholas D.; Glen, Fiona C.; Monter, Vera M.; Crabb, David P.

2014-01-01

328

Awareness and perception regarding eye donation in students of a nursing college in Bangalore  

Directory of Open Access Journals (Sweden)

Full Text Available Context: Corneal diseases constitute a significant cause of visual impairment and blindness in the developing world. The number of corneal transplants done is far less than the actual requirement in India. This is largely due to the inadequate number of corneas collected. Well-informed nursing students could be expected to influence eye donation rates. Aims: To assess the awareness and perception of 188 first- and second-year nursing students towards eye donation in Bangalore. Settings and Design: Cross-sectional study design. Materials and Methods: A pretested, semi-structured questionnaire. Statistical Analysis Used: Data were analyzed using the Epi-Info software package, Version 6.04. Results: The majority (96.8% of students knew that eyes can be donated after death but only 38.2% knew that the ideal time of donation was within 6 hours of death. Most participants (85.1% were either willing or had already donated their eyes. Nobility in the act of eye donation was the main motivational force for eye donation according to 85.6% of students. Perceived reasons for not pledging eyes by the students were: the unacceptable idea of separating the eyes from the body (67.9%, lack of awareness (42.8%, objection by family members (28.5%, and unsuitability to donate because of health problem (10.7%. Conclusion: This study revealed that nursing students were well aware of eye donations and most of them were inclined to sign-up for eye donation. The perceived reasons for not donating eyes need to be considered while creating awareness about eye donation in the community. The nursing students could be actively involved as volunteers in eye donation campaigns and they can act as counsellors for eye donors. They can also contribute by participating in creating awareness and motivating people to become eye donors.

Gupta Anita

2009-01-01

329

Optimisation procedures using `eye` merit function  

Energy Technology Data Exchange (ETDEWEB)

An easy to use and versatile design tool, which reduces the risk of having undesired reflectance values at wavelengths not covered by conventional calculations, is suggested for the optimization of optical coatings. It consists of the use of a merit function combined with the simplex optimization method to simulate the action of the human eye evaluating how much a calculated optical coating performance curve approaches the desired curve. An illustrative example is given of the design of wide band antireflection coating for the infrared range.

Piegari, A.; Emiliani, G.

1992-12-31

330

Flood-Related Eye Care Precautions  

Science.gov (United States)

... for Your Vision > Flood-Related Eye Care Precautions Flood-Related Eye Care Precautions As flooding continues to ... for contact lens wearers to avoid exposure to flood-related eye infections and complications Avoid contact with ...

331

Characterizing dual wavelength polarimetry through the eye for monitoring glucose.  

Science.gov (United States)

Diabetes is an insidious disease that afflicts millions of people worldwide and typically requires the person with the disease to monitor their blood sugar level via finger or forearm sticks multiple times daily. Therefore, the ability to noninvasively measure glucose would be a significant advancement for the diabetic community. The use of optically polarized light passed through the anterior chamber of the eye is one proposed noninvasive approach for glucose monitoring. However, the birefringence of the cornea and the difficulty in coupling the light across the eye have been major drawbacks toward realizing this approach. A dual wavelength optical polarimetric approach has been proposed as a means to potentially overcome the birefringence noise but has never been fully characterized. Therefore, in this paper an optical model has been developed along with experiments performed on New Zealand White rabbit eyes for characterizing the light path and corneal birefringence at two different wavelengths as they are passed through the anterior chamber of the eye. The results show that, without index matching, it is possible to couple the light in and out of the eye but only across a very limited range otherwise the light does not come back out of the eye. It was also shown that there is potential to use a dual wavelength approach to accommodate the birefringence noise of the cornea in the presence of eye motion. These results will be used to help guide the final design of the polarimetric system for use in noninvasive monitoring of glucose in vivo. PMID:21258546

Malik, Bilal H; Coté, Gerard L

2010-01-01

332

Eyes on the LHC  

CERN Multimedia

"Particle physicists don't know for sure what explorations at the Large Hadron Collider will bring. But they do know that many mysteries in their field point toward solutions at the LHC's impressive TeV energy scale."

Gianotti, Fabiola

2007-01-01

333

Unoperated eyes with persistent fetal vasculature.  

Digital Repository Infrastructure Vision for European Research (DRIVER)

PURPOSE: To present a follow-up on children with persistent fetal vasculature (PFV) when surgery was not performed. METHODS: From January 1992 through June 2001, 31 infants (31 eyes) with PFV were evaluated to document the number of eyes operated on versus eyes not operated on to determine whether the latter group remained stationary or became worse. RESULTS: Seventeen of the 31 eyes underwent surgery. Of the 14 eyes not undergoing surgery, 7 were judged to be inoperable. The remaining 7 eyes...

Gulati, Nishi; Eagle, Ralph C.; Tasman, William

2003-01-01

334

Semi-automatic evaluation of intraocular lenses (IOL) using a mechanical eye model  

Science.gov (United States)

As cataracts are the most common reason for loss of vision with an age over 55, the implantation of intraocular intraocular lenses is one of the most common surgical interventions. The quality measurement and test instructions for the patients. Therefore more efforts are put into the individualization of IOL in order to achieve better imaging properties. Two examples of typical quality standards for IOL are the modulated transfer function (MTF) and the Strehl ratio which can be measured in vivo or also in mechanical eye models. A mechanical eye model in the scale 1:1 is presented. It has been designed to allow the measurement of the MTF and Strehl ratio and simultaneous evaluation of physiological imaging quality. The eye model allows the automatic analysis of the IOL especially focused on the tolerance for tilting and decentering. Cornea, iris aperture and IOL type are interchangeable, because all these parts are implemented by the use of separated holders. The IOL is mounted on a shift plate. Both are mounted on a tilt plate. This set-up guarantees an independent decentration and tilt of the IOL, both moved by electrical drives. This set-up allows a two-dimensional tolerance analysis of decentration and tilt effects. Different 100×100 point (decentration×tilt) analyzes for various iris apertures, needing only approximately 15 minutes, are presented.

Drauschke, A.; Rank, E.; Forjan, M.; Traxler, L.

2013-03-01

335

Process of Designing Robust, Dependable, Safe and Secure Software for Medical Devices: Point of Care Testing Device as a Case Study  

Directory of Open Access Journals (Sweden)

Full Text Available This paper presents a holistic methodology for the design of medical device software, which encompasses of a new way of eliciting requirements, system design process, security design guideline, cloud architecture design, combinatorial testing process and agile project management. The paper uses point of care diagnostics as a case study where the software and hardware must be robust, reliable to provide accurate diagnosis of diseases. As software and software intensive systems are becoming increasingly complex, the impact of failures can lead to significant property damage, or damage to the environment. Within the medical diagnostic device software domain such failures can result in misdiagnosis leading to clinical complications and in some cases death. Software faults can arise due to the interaction among the software, the hardware, third party software and the operating environment. Unanticipated environmental changes and latent coding errors lead to operation faults despite of the fact that usually a significant effort has been expended in the design, verification and validation of the software system. It is becoming increasingly more apparent that one needs to adopt different approaches, which will guarantee that a complex software system meets all safety, security, and reliability requirements, in addition to complying with standards such as IEC 62304. There are many initiatives taken to develop safety and security critical systems, at different development phases and in different contexts, ranging from infrastructure design to device design. Different approaches are implemented to design error free software for safety critical systems. By adopting the strategies and processes presented in this paper one can overcome the challenges in developing error free software for medical devices (or safety critical systems.

Sivanesan Tulasidas

2013-08-01

336

Curvature of visual space under vertical eye rotation: implications for spatial vision and visuomotor control.  

Science.gov (United States)

Most models of spatial vision and visuomotor control reconstruct visual space by adding a vector representing the site of retinal stimulation to another vector representing gaze angle. However, this scheme fails to account for the curvatures in retinal projection produced by rotatory displacements in eye orientation. In particular, our simulations demonstrate that even simple vertical eye rotation changes the curvature of horizontal retinal projections with respect to eye-fixed retinal landmarks. We confirmed the existence of such curvatures by measuring target direction in eye coordinates in which the retinotopic representation of horizontally displaced targets curved obliquely as a function of vertical eye orientation. We then asked subjects to point (open loop) toward briefly flashed targets at various points along these lines of curvature. The vector-addition model predicted errors in pointing trajectory as a function of eye orientation. In contrast, with only minor exceptions, actual subjects showed no such errors, showing a complete neural compensation for the eye position-dependent geometry of retinal curvatures. Rather than bolstering the traditional model with additional corrective mechanisms for these nonlinear effects, we suggest that the complete geometry of retinal projection can be decoded through a single multiplicative comparison with three-dimensional eye orientation. Moreover, because the visuomotor transformation for pointing involves specific parietal and frontal cortical processes, our experiment implicates specific regions of cortex in such nonlinear transformations. PMID:10704510

Crawford, J D; Henriques, D Y; Vilis, T

2000-03-15

337

Autologous Serum In Eye Disorders  

Directory of Open Access Journals (Sweden)

Full Text Available While pharmaceutical lubricants offer little to nonutrition, eye drops made from autologous serum havea tear like biochemical character and supply nutritionalcomponents. In vitro studies have shown that serumsupports viability, proliferation and migration of ocularsurface epithelial cells better than unpreservedpharmaceutical tear substitutes. The productionparameters should be optimized before a meaningfulrandomized, controlled clinical trial attempts toevaluate the real therapeutic potential of this approachin ocular surface disorder. Meanwhile, the use ofserum eye drops remains an experimental approach.Itis a cost effective way of treating dry eye syndromewith minimal side effects.

Priyanka Sodani Mahajan

2009-07-01

338

Hospital epidemiology of dry eye  

Directory of Open Access Journals (Sweden)

Full Text Available One hundred consecutive cases of dry eye were studied to comment upon its epidemiological aspects. The incidence of dry eye amongst ophthalmic outpatients was 0.46% with a male:female ratio of 1:1.22. Fifty seven percent of the patients were above 50 years of age. The incidence was higher amongst outdoor workers and people from rural areas with poor socioeconomic status. The influence of hot and dry climate and nutritional status on dry eye incidence is discussed.

Khurana A

1991-01-01

339

Eyes in the Sky  

Science.gov (United States)

These shape-shifting galaxies have taken on the form of a giant mask. The icy blue eyes are actually the cores of two merging galaxies, called NGC 2207 and IC 2163, and the mask is their spiral arms. The false-colored image consists of infrared data from NASA's Spitzer Space Telescope (red) and visible data from NASA's Hubble Space Telescope (blue/green). NGC 2207 and IC 2163 met and began a sort of gravitational tango about 40 million years ago. The two galaxies are tugging at each other, stimulating new stars to form. Eventually, this cosmic ball will come to an end, when the galaxies meld into one. The dancing duo is located 140 million light-years away in the Canis Major constellation. The infrared data from Spitzer highlight the galaxies' dusty regions, while the visible data from Hubble indicates starlight. In the Hubble-only image (not pictured here), the dusty regions appear as dark lanes. The Hubble data correspond to light with wavelengths of .44 and .55 microns (blue and green, respectively). The Spitzer data represent light of 8 microns.

2006-01-01

340

Case study: improving the management of eye care programmes  

Directory of Open Access Journals (Sweden)

Full Text Available Nigeria is a federation of 36 administrative States, which each have a mandate to deliver health care to their population. Sightsavers International has been supporting four State ministries of health (Cross River, Kaduna, Kwara, and Sokoto in implementing programmes designed to provide comprehensive eye care services.Previously, eye care had been limited to services in big hospitals in the largest cities, which were inaccessible to the general population.These new eye care programmes have been very successful. The Kwara eye care programme (KWECP, for example, has increased the cataract surgical rate from 196 cataract operations per million per year in 2003 to 932 in 2007.This article describes what we have learnt from our experience in managing these programmes and hopefully will provide you with suggestions to improve management.

Kolawole Olumide Ogundimu

2008-12-01

 
 
 
 
341

Designing a Minimum Data Set for Breast Cancer: a Starting Point for Breast Cancer Registration in Iran  

Science.gov (United States)

Background: Due to the high incidence of deaths from breast cancer, high cost of treatment and limited resources, the need to formulate and implement effective programs in reducing the burden of disease is obvious. Care, control and creation of cancer information system having an infrastructure from collection of minimum data sets (MDS) are the top priorities of research in Iran’s Ministry of Health. Methods: This is an applied descriptive research with comparative approach implemented in 2010. MDS for breast cancer on selected countries were searched and reviewed and proposed model based on the country’s need was designed. Research data were implemented in 2 stages; assessment of MDS on selected countries and the validation of the proposed model through several meetings that has been carried out by the Undersecretary for Research and Technology and several oncologists and pathologists. Results: The MDS is composed of 11 parameters in the form of fields in closed structured arrangements with consideration to coding responses. These parameters include: hospital data, demography, referral, physical examination and investigation, diagnostic information, pathology, treatment, palliative care, completion of primary treatment, clinical trials and follow-up. This form is available for use in the cancer registry database. Conclusion: MDS provides an opportunity to strengthen communication between performed researches and research results for the improvement of programs, policies and strategies and provides positive effect on equality in the health system. Although the stages of creating the MDS for breast cancer has been successful, but many challenges has been met until its completion.

Ghaneie, M; Rezaie, A; Ghorbani, N R; Heidari, RN; Arjomandi, M; Zare, M

2013-01-01

342

Retinal images in the human eye with implanted intraocular lens  

Science.gov (United States)

A typical proceeding in cataract is based on the removal of opaque crystalline lens and inserting in its place the artificial intraocular lens (IOL). The quality of retinal image after such procedure depends, among others, on the parameters of the IOL, so the design of the implanted lens is of great importance. An appropriate choice of the IOL material, especially in relation to its biocompatibility, is often considered. However the parameter, which is often omitted during the IOL design is its chromatic aberration. In particular lack of its adequacy to the chromatic aberration of a crystalline lens may cause problems. In order to fit better chromatic aberration of the eye with implanted IOL to that of the healthy eye we propose a hybrid - refractive-diffractive IOL. It can be designed in such way that the total longitudinal chromatic aberration of an eye with implanted IOL equals the total longitudinal chromatic aberration of a healthy eye. In this study we compare the retinal image quality calculated numerically on the basis of the well known Liou-Brennan eye model with typical IOL implanted with that obtained if the IOL is done as hybrid (refractive-diffractive) design.

Zaj?c, Marek; Siedlecki, Damian; Nowak, Jerzy

2007-05-01

343

Combined approaches for drug design points the way to novel proline racemase inhibitor candidates to fight Chagas' disease.  

Science.gov (United States)

Chagas' disease is caused by Trypanosoma cruzi, a protozoan transmitted to humans by blood-feeding insects, blood transfusion or congenitally. Previous research led us to discover a parasite proline racemase (TcPRAC) and to establish its validity as a target for the design of new chemotherapies against the disease, including its chronic form. A known inhibitor of proline racemases, 2-pyrrolecarboxylic acid (PYC), is water-insoluble. We synthesized soluble pyrazole derivatives, but they proved weak or inactive TcPRAC inhibitors. TcPRAC catalytic site is too small and constrained when bound to PYC to allow efficient search for new inhibitors by virtual screening. Forty-nine intermediate conformations between the opened enzyme structure and the closed liganded one were built by calculating a transition path with a method we developed. A wider range of chemical compounds could dock in the partially opened intermediate active site models in silico. Four models were selected for known substrates and weak inhibitors could dock in them and were used to screen chemical libraries. Two identified soluble compounds, (E)-4-oxopent-2-enoic acid (OxoPA) and its derivative (E)-5-bromo-4-oxopent-2-enoic acid (Br-OxoPA), are irreversible competitive inhibitors that presented stronger activity than PYC on TcPRAC. We show here that increasing doses of OxoPA and Br-OxoPA hamper T. cruzi intracellular differentiation and fate in mammalian host cells. Our data confirm that through to their binding mode, these molecules are interesting and promising as lead compounds for the development of chemotherapies against diseases where active proline racemases play essential roles. PMID:23613764

Berneman, Armand; Montout, Lory; Goyard, Sophie; Chamond, Nathalie; Cosson, Alain; d'Archivio, Simon; Gouault, Nicolas; Uriac, Philippe; Blondel, Arnaud; Minoprio, Paola

2013-01-01

344

Combined Approaches for Drug Design Points the Way to Novel Proline Racemase Inhibitor Candidates to Fight Chagas' Disease  

Science.gov (United States)

Chagas’ disease is caused by Trypanosoma cruzi, a protozoan transmitted to humans by blood-feeding insects, blood transfusion or congenitally. Previous research led us to discover a parasite proline racemase (TcPRAC) and to establish its validity as a target for the design of new chemotherapies against the disease, including its chronic form. A known inhibitor of proline racemases, 2-pyrrolecarboxylic acid (PYC), is water-insoluble. We synthesized soluble pyrazole derivatives, but they proved weak or inactive TcPRAC inhibitors. TcPRAC catalytic site is too small and constrained when bound to PYC to allow efficient search for new inhibitors by virtual screening. Forty-nine intermediate conformations between the opened enzyme structure and the closed liganded one were built by calculating a transition path with a method we developed. A wider range of chemical compounds could dock in the partially opened intermediate active site models in silico. Four models were selected for known substrates and weak inhibitors could dock in them and were used to screen chemical libraries. Two identified soluble compounds, (E)-4-oxopent-2-enoic acid (OxoPA) and its derivative (E)-5-bromo-4-oxopent-2-enoic acid (Br-OxoPA), are irreversible competitive inhibitors that presented stronger activity than PYC on TcPRAC. We show here that increasing doses of OxoPA and Br-OxoPA hamper T. cruzi intracellular differentiation and fate in mammalian host cells. Our data confirm that through to their binding mode, these molecules are interesting and promising as lead compounds for the development of chemotherapies against diseases where active proline racemases play essential roles.

Berneman, Armand; Montout, Lory; Goyard, Sophie; Chamond, Nathalie; Cosson, Alain; d'Archivio, Simon; Gouault, Nicolas; Uriac, Philippe; Blondel, Arnaud; Minoprio, Paola

2013-01-01

345

[Dry eye: etiopathogenesis and treatment].  

Science.gov (United States)

Dry eye is a multifactorial disease of tears and ocular surface that causes discomfort, visual disturbance and tear film instability. It is a common disorder that affects specially adults and women and can cause quality of life impairment comparable to migraine, shortness of breath and chronic renal insufficiency, depending on its symptoms or complications. New concepts regarding physiopathology, classification and treatment have been presented and should be known by ophthalmologists because of their relevance on day-by-day application. There are about 100 different medications currently in use for dry eye besides other methods of treatment, so it is necessary to establish what is really safe and effective for dry eye. This paper presents a review about Dry Eye Syndrome etiopathogenesis and treatment. PMID:20549055

Fonseca, Ellen Carrara; Arruda, Gustavo Viani; Rocha, Eduardo Melani

2010-01-01

346

What is Diabetic Eye Disease?  

Medline Plus

Full Text Available ... at least half will show signs of a diabetic eye disease and the most common of these by far is the disease diagnosed in Mary -- diabetic retinopathy. Doctor: This is a condition that affects ...

347

If I Had - Dry Eyes  

Medline Plus

Full Text Available ... eyes. Dr. Asbell is a Professor of Ophthalmology at Mount Sinai School of Medicine and Director of the Cornea Service and Refractive Surgery Center at the Mount Sinai Medical Center. In addition, she ...

348

Eye-based head gestures  

DEFF Research Database (Denmark)

A novel method for video-based head gesture recognition using eye information by an eye tracker has been proposed. The method uses a combination of gaze and eye movement to infer head gestures. Compared to other gesture-based methods a major advantage of the method is that the user keeps the gaze on the interaction object while interacting. This method has been implemented on a head-mounted eye tracker for detecting a set of predefined head gestures. The accuracy of the gesture classifier is evaluated and verified for gaze-based interaction in applications intended for both large public displays and small mobile phone screens. The user study shows that the method detects a set of defined gestures reliably.

Mardanbegi, Diako; Witzner Hansen, Dan

2012-01-01

349

If I Had - Dry Eyes  

Medline Plus

Full Text Available ... ophthalmologist is going to ask you about your problem. They're also going to take a look ... Dr. Asbell: Dry eye is probably a multifactorial problem, meaning there are many things that can lead ...

350

Eye Movements When Viewing Advertisements  

Directory of Open Access Journals (Sweden)

Full Text Available In this selective review, we examine key findings on eye movements when viewing advertisements. We begin with a brief, general introduction to the properties and neural underpinnings of saccadic eye movements. Next, we provide an overview of eye movement behavior during reading, scene perception, and visual search, since each of these activities is, at various times, involved in viewing ads. We then review the literature on eye movements when viewing print ads and warning labels (of the kind that appear on alcohol and tobacco ads, before turning to a consideration of advertisements in dynamic media (television and the Internet. Finally, we propose topics and methodological approaches that may prove to be useful in future research.

EmilyHiggins

2014-03-01

351

If I Had - Dry Eyes  

Medline Plus

Full Text Available ... its severity. We are beginning to get a feel for classify dry eye disease and how best ... out with the best opportunity to make you feel better. And that is what you are doing; ...

352

Conjunctivitis (Pink Eye) in Newborns  

Science.gov (United States)

... Smart: Know When Antibiotics Work Adenovirus Non-Polio Enterovirus Parent Portal Conjunctivitis (Pink Eye) in Newborns On ... Smart: Know When Antibiotics Work Adenovirus Non-Polio Enterovirus Parent Portal File Formats Help: How do I ...

353

Nutrition and the Aging Eye  

Science.gov (United States)

... participated in the Age-Related Eye Disease Study (AREDS), a nationwide clinical trial launched by the National ... results from which were published in 2001. The AREDS study showed that an experimental combination of three ...

354

What is Diabetic Eye Disease?  

Medline Plus

Full Text Available ... stages of diabetic retinopathy, these vessels weaken and break. The result is a leakage of fluid that ... stages, new and abnormally fragile vessels form and break which produces bleeding in the eye. Eventually this ...

355

Community Eye Health MSc dissertations  

Directory of Open Access Journals (Sweden)

Full Text Available The seven Exchange articles that follow are based on the dissertations of students at the International Centre for Eye Health, London School of Hygiene and Tropical Medicine, who graduated in 2008.

Osman L

2008-12-01

356

EyeSim--an ophthalmic response simulator.  

Science.gov (United States)

This paper pertains to the design, construction and development of an ophthalmic response simulator, intended to augment current neurological examination teaching practices in medical schools. Neurological examination of the eyes informs a practitioner of the functional state of certain cranial nerves (II, III, IV and VI) through the assessment of visual acuity, visual fields, ocular movements, external and internal eye structures and ophthalmoscopic examination. For the medical student, the interpretation of these indicators may be difficult, compounded by the infrequence with which such patients may be presented. As such, the need was identified for a simulator capable of replicating the ophthalmic response of patients with typical and a range of atypical neurologies. Such a simulator could be used as a stand-alone device or developed toward inclusion in pre-existing, life-size, hi-fidelity mannequins. Specifically, EyeSim will be able to track the movements of a pen-torch and vary the apparent dilation of an iris in response to changing levels of illumination. These responses can then be modulated to reflect certain deficits that neural pathologies may cause. At present the simulator comprises the electrical, electronic and mechanical components that replicate the pupillary response of the iris and the motility of the ocular muscles, a computer for the reception and analysis of a video signal and the micro-controller components, which determine the action of the physical components based on an array of inputs. PMID:16623227

Nelson, Tim; Reynolds, Karen; Owen, Harry

2006-03-01

357

B-EYE: The World Through the Eyes of a Honey Bee  

Science.gov (United States)

One of the great treats awaiting Scouts (or any others who learn to search the Web efficiently) is the large number of high quality science Websites put forth by Australian research institutions. B-EYE is yet another such wonderful site. Dr. Andrew Giger, a neuroscientist studying insect vision at the Centre for Visual Science (CVS) at Australian National University, put together this site so visitors could see the world "through the eyes of a honey bee." Although simplified to grayscale images (bees view colors differently than humans), the visual distortions (from human to bee) are fascinating and highly educational. The well-designed site takes the viewer through the specific elements of each visual distortion, offering descriptions, a gallery of pre-processed images, and several options for viewing. The most sophisticated option allows users to set parameters (distance to pattern, horizontal and vertical position, background intensity, etc.) to view a series of images through a human eye, a simulated projection, and eventually, a bee's eye.

Giger, Andrew.

1995-01-01

358

Perspectives on primary eye care  

Directory of Open Access Journals (Sweden)

Full Text Available We think of primary eye care (PEC, and any kind of primary health care (PHC, as a ‘frontline’ activity, providing care and identifying disease before it becomes a serious medical issue. However, as this course showed, even a cursory review of systems across the world reveals that there is no common understanding of what primary eye care means and there exists a wide variation both in its content and in the way in which it is delivered.

GVS Murthy

2009-03-01

359

Dry eye and Meige's syndrome  

Digital Repository Infrastructure Vision for European Research (DRIVER)

AIMS—To determine the relation between dry eye and Meige's syndrome.?METHODS—325 patients with dry eye were divided into those responsive to topical and other forms of treatment (n=276) and those who were not (n=49). A neuropsychiatric examination was performed to check for Meige's syndrome in the latter group.?RESULTS—Twenty eight (57%) of the treatment unresponsive patients were diagnosed with Meige's syndrome.?CONCLUSIONS—There is a subgroup of patients with dry e...

Tsubota, K.; Fujihara, T.; Kaido, M.; Mori, A.; Mimura, M.; Kato, M.

1997-01-01

360

Increased drift in amblyopic eyes.  

Digital Repository Infrastructure Vision for European Research (DRIVER)

Reports are conflicting on the presence of increased drift in amblyopic eyes. Furthermore, the individual effects of either amblyopia or strabismus alone on ocular drift have not been systematically investigated. We therefore used a photoelectric method to record horizontal eye position during monocular and binocular fixation in patients having amblyopia without strabismus, intermittent strabismus, or constant strabismus amblyopia. Our principal finding was increased drift amplitude (up to 3....

Ciuffreda, K. J.; Kenyon, R. V.; Stark, L.

1980-01-01

 
 
 
 
361

EYE TRACKING WITH WEB CAMERA  

Digital Repository Infrastructure Vision for European Research (DRIVER)

The diploma presents two methods for detection of eye position on digital images and extensive analysis of the results. First, the method for detecting faces and eyes is presented. Then, the algorithms for Hough transformation and radial symmetry are described. The emphasis is on radial symmetry, because the algorithm was implemented by us with help of the open source library Emgu.CV and the .NET framework.

2011-01-01

362

Post-LASIK dry eye  

Digital Repository Infrastructure Vision for European Research (DRIVER)

Laser-assisted in situ keratomileusis (LASIK) is a frequently performed corneal refractive surgery with excellent refractive outcomes. The most common complication of LASIK is dry eyes, with virtually all patients developing some degree of dryness in the immediate postoperative period. Identifying preoperative dry eyes, and conscientious attention and treatment in the perioperative time period, can lead to enhanced patient satisfaction and more accurate visual outcomes. Improved understanding...

Shtein, Roni M.

2011-01-01

363

Mitochondrial disorders and the eye  

Digital Repository Infrastructure Vision for European Research (DRIVER)

Nicole J Van Bergen, Rahul Chakrabarti, Evelyn C O'Neill, Jonathan G Crowston, Ian A TrounceCentre for Eye Research Australia, Department of Ophthalmology, University of Melbourne, Victoria, AustraliaAbstract: The clinical significance of disturbed mitochondrial function in the eye has emerged since mitochondrial DNA (mtDNA) mutation was described in Leber's hereditary optic neuropathy. The spectrum of mitochondrial dysfunction has become apparent through increased understanding of th...

2011-01-01

364

The interblink interval in normal and dry eye subjects  

Directory of Open Access Journals (Sweden)

Full Text Available Patrick R Johnston,1 John Rodriguez,1 Keith J Lane,1 George Ousler,1 Mark B Abelson1,21Ora, Inc, Andover, MA, USA; 2Schepens Eye Research Institute and Harvard Medical School, Boston, MA, USAPurpose: Our aim was to extend the concept of blink patterns from average interblink interval (IBI to other aspects of the distribution of IBI. We hypothesized that this more comprehensive approach would better discriminate between normal and dry eye subjects.Methods: Blinks were captured over 10 minutes for ten normal and ten dry eye subjects while viewing a standardized televised documentary. Fifty-five blinks were analyzed for each of the 20 subjects. Means, standard deviations, and autocorrelation coefficients were calculated utilizing a single random effects model fit to all data points and a diagnostic model was subsequently fit to predict probability of a subject having dry eye based on these parameters.Results: Mean IBI was 5.97 seconds for normal versus 2.56 seconds for dry eye subjects (ratio: 2.33, P = 0.004. IBI variability was 1.56 times higher in normal subjects (P < 0.001, and the autocorrelation was 1.79 times higher in normal subjects (P = 0.044. With regard to the diagnostic power of these measures, mean IBI was the best dry eye versus normal classifier using receiver operating characteristics (0.85 area under curve (AUC, followed by the standard deviation (0.75 AUC, and lastly, the autocorrelation (0.63 AUC. All three predictors combined had an AUC of 0.89. Based on this analysis, cutoffs of ?3.05 seconds for median IBI, and ?0.73 for the coefficient of variation were chosen to classify dry eye subjects.Conclusion: (1 IBI was significantly shorter for dry eye patients performing a visual task compared to normals; (2 there was a greater variability of interblink intervals in normal subjects; and (3 these parameters were useful as diagnostic predictors of dry eye disease. The results of this pilot study merit investigation of IBI parameters on a larger scale study in subjects with dry eye and other ocular surface disorders.Keywords: dry eye, interblink intervals, visual function, visual tasks, diagnostic model

Johnston PR

2013-02-01

365

Causes of eye removal: Analysis of 586 eyes  

Directory of Open Access Journals (Sweden)

Full Text Available Background/Aim. Eye enucleation is one of the oldest surgical procedures. The aim of the study was to determine the causes of enucleation as seen in a major reference eye center in Serbia. Methods. Retrospective case series involving a review of all enucleation procedures performed in the period between January 2000 and December 2008 at the Institute for Eye Diseases, Clinical Center of Serbia, Belgrade. The collected information included the basic demographic data and diagnosis of the affected eye. The diagnosis was made based on history, clinical and histological examinations. Clinical indications for enucleation were categorized as tumors, glaucoma, trauma, infections and other diseases. A statistical analysis was made using the Student's t-test. Results. There were 586 patients, 315 male and 271 female in our series. The mean age was 57.81, ranging from 3 months to 96 years. The most common cause of enucleations was tumor (76.11%, (p < 0.05. Choroid melanoma was the most common etiology leading to enucleation (81.18%, followed by retinoblastoma (12.34%. A total of 8.02% of enucleations were performed due to glaucoma that was primarily neovascular in 42.55% of cases or caused by trauma in 38.8% of cases. Trauma was the third common etiology of enucleation, and it was acute in 56.26% of cases or resulted in phthisis bulbi in 31.25% of cases. Enucleation caused by inflammation was performed in 2.90% of cases, out of which 52.94% of enucleations occurred after perforation of the cornea. In the group of other diseases the most common cause of enucleation was atrophy of the eye ball. Conclusion. Neoplasm, neovascular glaucoma, acute eye injury and atrophy of the eye ball are the most common causes of enucleation.

Kneževi? Miroslav

2013-01-01

366

Red eye: the role of primary care  

Directory of Open Access Journals (Sweden)

Full Text Available One of the most common eye problems to present to health workers is acute red eye(s. Approximately 40% of all outpatients seen in Bawku, Ghana, and in ten district hospitals in Pakistan, present with red eyes (Figure 1.

Allen Foster

2005-03-01

367

Are 3-D Movies Bad for Your Eyes?  

Medline Plus

Full Text Available ... Alerts Are 3-D Movies Bad for Your Eyes? Tweet Eye Health Lifestyle Topics Preventing Eye Injuries Healthy Eyes ... when viewing 3-D digital images. Find An Eye M.D. Enter zip code here Search by ...

368

Are 3-D Movies Bad for Your Eyes?  

Medline Plus

Full Text Available ... Eyes & the Sun Eye Health News Consumer Alerts Are 3-D Movies Bad for Your Eyes? Tweet ... eye care provider for your condition or treatment. Are You Fit at 40? A baseline eye exam ...

369

Are 3-D Movies Bad for Your Eyes?  

Medline Plus

Full Text Available ... 40 to 60 Adults Over 60 Babies & Children Computer Usage Diabetes Diet & Nutrition Eye Injuries Eye Screening ... Topics Preventing Eye Injuries Healthy Eyes During Pregnancy Computer Usage & Eye Strain Maintaining Your Sight with Diabetes ...

370

Are 3-D Movies Bad for Your Eyes?  

Medline Plus

Full Text Available ... Eye Injuries Healthy Eyes During Pregnancy Computer Usage & Eye Strain Maintaining Your Sight with Diabetes Sports and Eye Protection Eyesight Risks for Smokers Veterans & Eye Health ...

371

Are 3-D Movies Bad for Your Eyes?  

Medline Plus

Full Text Available ... D Movies Bad for Your Eyes? Tweet Eye Health Lifestyle Topics Preventing Eye Injuries Healthy Eyes During ... 31 Quiz Take a poll! Subscribe for Eye Health Info Sign up for our monthly e-mail ...

372

Eye-based head gestures for interaction in the car  

DEFF Research Database (Denmark)

In this paper we suggest using a new method for head gesture recognition in the automotive context. This method involves using only the eye tracker for measuring the head movements through the eye movements when the gaze point is fixed. It allows for identifying a wide range of head gestures that can be used as an alternative input in the multimodal interaction context. Two approaches are described for using this method for interaction with objects inside or outside the car. Some application examples are described where the discrete or continuous head movements in combination with the driverâ??s visual attention can be used for controlling the objects inside the car.

Mardanbeigi, Diako; Witzner Hansen, Dan

373

Fluorophotometry as a diagnostic tool for the evaluation of dry eye disease  

Directory of Open Access Journals (Sweden)

Full Text Available Abstract Background Dry eye disease is a common debilitating ocular disease. Current diagnostic tests used in dry eye disease are often neither sensitive nor reproducible, making it difficult to accurately diagnose and determine end points for clinical trials, or evaluate the usefulness of different medications in the treatment of dry eye disease. The recently developed fluorophotometer can objectively detect changes in the corneal epithelium by quantitatively measuring its barrier function or permeability. The purpose of the study is to investigate the use of corneal fluorescein penetration measured by the fluorophotometer as a diagnostic tool in the evaluation of dry eye patients. Methods Dry eye patients (16 eyes, who presented with a chief complaint of ocular irritation corresponding with dry eye, low Schirmer's one test ( Results Ten minutes after fluorescein installition, patients with dry eye disease averaged a five-fold increase in corneal tissue fluorescein concentration (mean = 375.26 ± 202.67 ng/ml compared with that of normal subjects (mean = 128.19 ± 85.84 ng/ml. Sixty minutes after dye installation, patients with dry eye disease still revealed higher corneal tissue fluorescein concentration (mean = 112.87 ± 52.83 ng/ml compared with that of controls (mean = 40.64 ± 7.96 ng/ml, averaging a three-fold increase. Conclusion Patients with dry eye disease demonstrated an increased corneal permeability and a slower rate of elimination to topically administered fluorescein when measured by the fluorophotometer. This suggests that fluorophotometry may serve as a valuable quantitative and objective tool for the diagnosis of dry eye disease, and in following patients' response to new treatment modalities. Fluorophotometry may serve as an objective non-invasive tool for end-point analysis in clinical trials of new treatments for dry eye disease.

Fan Vincent C

2006-05-01

374

Calibration of an eye oximeter with a dynamic eye phantom  

Science.gov (United States)

Measurements of oxygen saturation and flow in the retina can yield information about the eye health and the onset of eye pathologies such as Diabetic Retinopathy. Recently we have realized an instrument capable of measuring oxygenation in the retina using six different wavelengths and capable of measuring blood flow using speckle-based techniques. The calibration of such instrument is particularly difficult due to the layered structure of the eye and the lack of alternative measurement techniques. For this purpose we have realized an in vitro model of the human eye. The artificial eye is composed of four layers: the retina vessels, the choroids, the retinal pigmented epithelium (RPE), and the sclera. The retina vessels are modeled with 150 ?m tube connected to a micro-pump delivering 34 ?l/min. The micro-tube, the pump, and a blood reservoir were connected in a closed circulatory system; blood oxygenation in the vessel could be modified using an external oxygen reservoir. The optical properties of all other layers were mimicked using titanium dioxide as a scatterer and ink as an absorber. The absorption coefficient ?a and the scattering coefficient µs of these layers were independently measured using an integrating sphere. Absorption and scattering coefficient of all layers were modified before experimental measurements and a Monte Carlo program was finally used to model the experimental results.

Nabili, A.; Bardakci, D.; Helling, K.; Matyas, C.; Muro, S.; Ramella-Roman, J. C.

2008-02-01

375

On subwavelength imaging with Maxwell's fish eye lens  

CERN Multimedia

Both explicit analysis and FEM numerical simulation are used to analyze the field distribution of a line current in the so-called Maxwell's fish eye lens [bounded with a perfectly electrical conductor (PEC) boundary]. We show that such a 2D Maxwell's fish eye lens cannot give perfect imaging due to the fact that high order modes of the object field can hardly reach the image point in Maxwell's fish eye lens. If only zeroth order mode is excited, a subwavelength image of a sharp object may be achieved in some cases, however, its spot-size is larger than the spot size of the initial object field. The image resolution is determined by the field spot size of the image corresponding to the zeroth order component of the object field. Our explicit analysis consists very well with the FEM results for a fish eye lens. Time-domain simulation is also given to verify our conclusion. Multi-point imaging for a single object point is also demonstrated.

Sun, Fei

2010-01-01

376

Can Maxwell's fish eye lens really give perfect imaging?  

CERN Multimedia

Both explicit analysis and FEM numerical simulation are used to analyze the field distribution of a line current in the so-called Maxwell's fish eye lens [bounded with a perfectly electrical conductor (PEC) boundary]. We show that such a 2D Maxwell's fish eye lens cannot give perfect imaging due to the fact that high order modes of the object field can hardly reach the image point in Maxwell's fish eye lens. If only zeroth order mode is excited, a good image of a sharp object may be achieved in some cases, however, its spot-size is larger than the spot size of the initial object field. The image resolution is determined by the field spot size of the image corresponding to the zeroth order component of the object field. Our explicit analysis consists very well with the FEM results for a fish eye lens. Time-domain simulation is also given to verify our conclusion. Multi-point images for a single object point are also demonstrated.

Sun, Fei

2010-01-01

377

Trustworthy-Looking Face Meets Brown Eyes  

Digital Repository Infrastructure Vision for European Research (DRIVER)

We tested whether eye color influences perception of trustworthiness. Facial photographs of 40 female and 40 male students were rated for perceived trustworthiness. Eye color had a significant effect, the brown-eyed faces being perceived as more trustworthy than the blue-eyed ones. Geometric morphometrics, however, revealed significant correlations between eye color and face shape. Thus, face shape likewise had a significant effect on perceived trustworthiness but only for male faces, the eff...

Kleisner, Karel; Priplatova, Lenka; Frost, Peter; Flegr, Jaroslav

2013-01-01

378

Health claims database study of cyclosporine ophthalmic emulsion treatment patterns in dry eye patients  

Directory of Open Access Journals (Sweden)

Full Text Available Karl G Stonecipher,1 Jenny Chia,2 Ahunna Onyenwenyi,2 Linda Villanueva,2 David A Hollander2 1TLC Laser Eye Centers, Greensboro, NC, 2Allergan, Inc., Irvine, CA, USA Background: Dry eye is a multifactorial, symptomatic disease associated with ocular surface inflammation and tear film hyperosmolarity. This study was designed to assess patterns of topical cyclosporine ophthalmic emulsion 0.05% (Restasis® use in dry eye patients and determine if there were any differences in use based on whether dry eye is physician-coded as a primary or nonprimary diagnosis. Methods: Records for adult patients with a diagnosis of dry eye at an outpatient visit from January 1, 2008 to December 31, 2009 were selected from Truven Health MarketScan® Research Databases. The primary endpoint was percentage of patients with at least one primary versus no primary dry eye diagnosis who filled a topical cyclosporine prescription. Data analyzed included utilization of topical corticosteroids, oral tetracyclines, and punctal plugs. Results: The analysis included 576,416 patients, accounting for 875,692 dry eye outpatient visits: 74.7% were female, 64.2% were ages 40-69 years, and 84.4% had at least one primary dry eye diagnosis. During 2008–2009, 15.9% of dry eye patients with a primary diagnosis versus 6.5% with no primary diagnosis filled at least one cyclosporine prescription. For patients who filled at least one prescription, the mean months’ supply of cyclosporine filled over 12 months was 4.44. Overall, 33.9% of dry eye patients filled a prescription for topical cyclosporine, topical corticosteroid, or oral tetracycline over 2 years. Conclusion: Patients with a primary dry eye diagnosis were more likely to fill a topical cyclosporine prescription. Although inflammation is key to the pathophysiology of dry eye, most patients seeing a physician for dry eye may not receive anti-inflammatory therapies. Keywords: corticosteroids, cyclosporine, dry eye syndromes, inflammation, medication adherence

Stonecipher KG

2013-10-01

379

Design and fabrication of a miniaturization micro volume auto titrator coupled with electrochemical end-point detector for the determination of acidity of some fruit juice  

Directory of Open Access Journals (Sweden)

Full Text Available A miniaturization micro volume auto titrator coupled with electrochemical end-point detector was designed and fabricated for the determination of acidity of some Thai citrus fruit juices collected in the northern area of Thailand. The method was based on on-line potentiometric titration of the acid contents with sodium hydroxide. Conditions such as volume of fruit juice sample, volume and concentration of potassium chloride used as supporting electrolyte and flow rate of titrant were optimized by using univariate optimization. A sample throughput of 83 samples h-1 at 0.28 mL/min was achieved with satisfactory results. The results obtained by the proposed method agreed with those obtained by using the standard classical titration method.

Prinya Masawat

2008-06-01

380

Experimental correlation-based identification of X-ray CT point spread function. Part 2: Simulation and design of input signal.  

Science.gov (United States)

The preferred signals for non-parametric correlation-based point spread function identification are white noise or pseudo-random binary sequences (PRBSs). Given the difficulty of building a phantom based on either of these signals, a new input is devised that corresponds to pseudo-randomly located holes. The positions of the holes correspond to zeros in a 2-D PRBS. To optimise the design of the phantom and to ensure proper imaging procedure, a number of simulations are conducted. The effects of the following parameters on identification quality are investigated: the size of the holes and their minimum separation, the period of the PRBS, input-output translational and rotational mis-registration, pixel size and the presence of cupping. The factors affecting identification quality the most are rotational alignment, hole size and separation, as well as sequence length. During simulations, a point spread function offering characteristics similar to the Philips Tomoscan CX is identified. Optimal results are obtained when the signal consists of 0.6 mm holes, separated by 0.9 mm, whose position is based on a 32 x 32 PRBS generated with a ten-stage shift-register. When adequate rotational alignment is provided, it is shown that the pseudo-randomly located holes signal is a good substitute for a purely white signal when identifying the PSF of a CT scanner. PMID:9136184

Doré, S; Kearney, R E; De Guise, J A

1997-01-01

 
 
 
 
381

Severe dry-eye syndrome following external beam irradiation  

International Nuclear Information System (INIS)

There are limited data in the literature on the probability of dry-eye complications according to radiotherapy dose. This study investigates the risk of radiation-induced severe dry-eye syndrome in patients in whom an entire orbit was exposed to fractionated external beam irradiation. Between October 1964 and May 1989, 33 patients with extracranial head and neck tumors received irradiation of an entire orbit. Most patients were treated with 60Co. The dose to the lacrimal apparatus was calculated at a depth of 1 cm from the anterior skin surface, the approximate depth of the major lacrimal gland. The end point of the study was severe dry-eye syndrome sufficient to produce visual loss secondary to corneal opacification, ulceration, or vascularization. Twenty patients developed severe dry-eye syndrome. All 17 patients who received dose ?57Gy developed severe dry-eye syndrome. Three (19%) of 16 patients who received doses ?45 Gy developed severe dry-eye syndrome; injuries in the latter group were much more slower to develop (4 to 11 years) than in the higher dose group, in whom corneal vascularization and opacification were usually pronounced within 9-10 months. There were no data for the range of doses between 45.01 and 56.99 Gy. The data did not suggest an increased risk of severe dry-eye syndrome with increasing age. Data from the current series and the literature are combined to construct a sigmoid dose response curve. The incidence of injury increases from 0% reported after doses ?30 Gy to 100% after doses ?57 Gy. 13 refs., 3 figs., 5 tabs

1994-11-15

382

Monitoring the eye lens: which dose quantity is adequate?  

Energy Technology Data Exchange (ETDEWEB)

Recent epidemiological studies suggest a rather low dose threshold (below 0.5 Gy) for the induction of a cataract of the eye lens. Some other studies even assume that there is no threshold at all. Therefore, protection measures have to be optimized and current dose limits for the eye lens may be reduced in the future. The question of which personal dose equivalent quantity is appropriate for monitoring the dose to the eye lens arises from this situation. While in many countries dosemeters calibrated in terms of the dose equivalent quantity H{sub p}(0.07) have been seen as being adequate for monitoring the dose to the eye lens, this might be questionable in the case of reduced dose limits and, thus, it may become necessary to use the dose equivalent quantity H{sub p}(3) for this purpose. To discuss this question, the dose conversion coefficients for the equivalent dose of the eye lens (in the following eye lens dose) were determined for realistic photon and beta radiation fields and compared with the values of the corresponding conversion coefficients for the different operational quantities. The values obtained lead to the following conclusions: in radiation fields where most of the dose comes from photons, especially x-rays, it is appropriate to use dosemeters calibrated in terms of H{sub p}(0.07) on a slab phantom, while in other radiation fields (dominated by beta radiation or unknown contributions of photon and beta radiation) dosemeters calibrated in terms of H{sub p}(3) on a slab phantom should be used. As an alternative, dosemeters calibrated in terms of H{sub p}(0.07) on a slab phantom could also be used; however, in radiation fields containing beta radiation with the end point energy near 1 MeV, an overestimation of the eye lens dose by up to a factor of 550 is possible.

Behrens, R [Physikalisch-Technische Bundesanstalt, Bundesallee 100, D-38116 Braunschweig (Germany); Dietze, G, E-mail: rolf.behrens@ptb.d [Paracelsusstrasse 7, D-38116 Braunschweig (Germany)

2010-07-21

383

Choosing Wisely When It Comes to Eye Care: Antibiotics for Eye Injections  

Science.gov (United States)

... Lens-Related Infections Detached & Torn Retina Diabetic Retinopathy Dry Eye Floaters & Flashes Glaucoma Hyperopia (Farsightedness) Low Vision Myopia ( ... Antibiotics for eye injections; and Punctal plugs for dry eye . This is the fourth in a series of ...

384

Choosing Wisely When It Comes to Eye Care: Punctal Plugs for Dry Eye  

Science.gov (United States)

... of Our 5-Part Series: Punctal Plugs for Dry Eye Making healthy lifestyle choices can help you protect ... discuss each item in detail. Punctal Plugs for Dry Eye Dry eye is a condition that millions of ...

385

Videos from the National Eye Institute: Eye Diseases | NIH MedlinePlus the Magazine  

Science.gov (United States)

... this page please turn Javascript on. Feature: Vision Videos from the National Eye Institute: Eye Diseases Past ... the early detection of eye disease. Share these videos with friends, family and colleagues. www.nei.nih. ...

386

Evaluation of Corneal Deformation Analyzed with Scheimpflug Based Device in Healthy Eyes and Diseased Ones  

Science.gov (United States)

This study was designed to evaluate the correlation between corneal biomechanical and morphological data in healthy eyes, eyes that underwent myopic photorefractive keratectomy (PRK), keratoconus affected eyes, and keratoconus affected eyes that underwent corneal collagen crosslinking (CCC). Complete clinical eye examination of all eyes was followed by tomographic (Pentacam, Oculus, Wetzlar, Germany) and biomechanical (Corvis ST, Oculus, Wetzlar, Germany) evaluation. Differences among Corvis ST (CST) parameters in the different groups have been performed. Linear regression between central corneal thickness (CCT), intraocular pressure (IOP), and anterior corneal curvature measured with Sim'K (KM), versus corneal deformation parameters measured with Corvis ST in the different groups, has been run using SPSS software version 18.0. We evaluated 64 healthy eyes of 64 patients with a mean refractive error of ?0.65 ± 1.68?D (measured as spherical equivalent), 17 eyes of 17 patients that underwent myopic PRK for a mean refractive defect of ?4.91 ± 2.05?D (measured as spherical equivalent), 16 eyes of 16 patients affected by keratconus (stage 2-3 of Amsler Classification), and 13 eyes of 13 patients affected by keratoconus that underwent CCC. Our data suggest that corneal curvature would have a greater influence on corneal deformation than CCT; in fact KM values are more strongly associated with more CST parameters both about corneal change in shape and both about the corneal ability to come back at original shape.

Lanza, Michele; Cennamo, Michela; Iaccarino, Stefania; Irregolare, Carlo; Bifani, Mario; Gironi Carnevale, Ugo Antonello

2014-01-01

387

Eye gaze in intelligent user interfaces gaze-based analyses, models and applications  

CERN Multimedia

Remarkable progress in eye-tracking technologies opened the way to design novel attention-based intelligent user interfaces, and highlighted the importance of better understanding of eye-gaze in human-computer interaction and human-human communication. For instance, a user's focus of attention is useful in interpreting the user's intentions, their understanding of the conversation, and their attitude towards the conversation. In human face-to-face communication, eye gaze plays an important role in floor management, grounding, and engagement in conversation.Eye Gaze in Intelligent User Interfac

Nakano, Yukiko I; Bader, Thomas

2013-01-01

388

Patient Reported Differences in Dry Eye Disease between Men and Women: Impact, Management, and Patient Satisfaction  

Digital Repository Infrastructure Vision for European Research (DRIVER)

Purpose Dry eye disease affects women twice as often as men, but there is little information on whether dry eye treatments, treatment satisfaction, or the impact of dry eye disease on patients’ lives and vision might differ by sex. Design: Questionnaire survey of 4000 participants in the Women’s Health Study and the Physicians’ Health Studies I and II with a prior report of a diagnosis of DED. Methods: Among participants who re-confirmed a diagnosis of dry eye disease, we assessed sympt...

Schaumberg, Debra A.; Uchino, Miki; Christen, William G.; Semba, Richard D.; Buring, Julie E.; Li, Jim Z.

2013-01-01

389

Radiation effects on eye components  

Science.gov (United States)

The most important water-soluble components of the vertebrate eye (lens proteins, aqueous humor, vitreous, hyaluronic acid, ascorbic acid) have been investigated in aqueous solution, after preceding X- or UV-irradiation. Spectroscopic, chromatographic, electrophoretic, hydrodynamic and analytic techniques have been applied, to monitor several radiation damages such as destruction of aromatic and sulfur-containing amino acids, aggregation, crosslinking, dissociation, fragmentation, and partial unfolding. Various substances were found which were able to protect eye components effectively against radiation, some of them being also of medical relevance.

Durchschlag, H.; Fochler, C.; Abraham, K.; Kulawik, B.

1999-08-01

390

The cure for lazy eye.  

Science.gov (United States)

The use of the term lazy eye blurs the distinction between amblyopia and strabismus, often causing parents to confuse the two problems. Parents often infer a causal explanation from the descriptive term, lazy eye. This misunderstanding causes parents to believe the child may outgrow the disorder. Therefore, an opportunity for early treatment during the important formative years may be lost. The correctly informed and knowledgeable parent will be more active and responsible in making sure that the child, especially the noncompliant child, follows the advised treatment. PMID:2366252

Kaye, B

1990-01-01

391

Collie eye anomaly in Switzerland  

Digital Repository Infrastructure Vision for European Research (DRIVER)

In this retrospective study, the results of 3’527 eye examinations in 6 different breeds affected with Collie Eye Anomaly (CEA) over a period of 8 years (1999 - 2007) are described. CEA was divided into three main ophthalmoscopic features, a) choroidal hypoplasia (CRH), b) CRH and coloboma and c) coloboma alone. Of the 101 Smooth Collies 8.9 % showed signs of CRH, whereas 36.9 % of Rough Collies were affected with CRH, 2.8 % with CRH and coloboma and 0.38 % with coloboma alone. Choroidal hy...

Walser-reinhardt, L.; Ha?ssig, M.; Spiess, B. M.

2009-01-01

392

Experiment design for through-focus testing of intraocular lenses  

Science.gov (United States)

Eye models to test intraocular lenses (IOLs) in an optical bench are commonly designed in agreement with the ISO 11979-2 and 11979-9 standard requirements. However, modifications to the ISO eye model have been proposed to test IOLs in conditions closer to real human eye. Wavefront analysis and aberration characterization, wavelength dependence, efficiency, off-axis performance and imaging degradation under certain amount of misalignment can thus be measured in vitro. The main parts of the system to test IOLs are: the illumination system and object test, the eye model including the IOL immersed in a wet cell and a microscope assembled to a sensor that magnifies and captures the aerial image of the object formed by the eye model. A problem concerning the simultaneous variation of defocus and magnification arises when using the microscope to capture out-of-focus images in a through-focus study. Using the eye model, we study the problem of implementing a through-focus measurement of the imaging quality of an IOL. We find a solution based on geometrical optics and compare it with other proposals reported in the literature. The effects on the measurement of the Modulation Transfer Function and the Point Spread Function are predicted. Experimental results are obtained and discussed.

Millán, María. S.; Alba-Bueno, Francisco; Vega, Fidel

2013-11-01

393

Virtual pharmacokinetic model of human eye.  

Science.gov (United States)

A virtual pharmacokinetic 3D model of the human eye is built using Comsol Multiphysics® software, which is based on the Finite Element Method (FEM). The model considers drug release from a polymer patch placed on sclera. The model concentrates on the posterior part of the eye, retina being the target tissue, and comprises the choroidal blood flow, partitioning of the drug between different tissues and active transport at the retina pigment epithelium (RPE)-choroid boundary. Although most straightforward, in order to check the mass balance, no protein binding or metabolism is yet included. It appeared that the most important issue in obtaining reliable simulation results is the finite element mesh, while time stepping has hardly any significance. Simulations were extended to 100,000s. The concentration of a drug is shown as a function of time at various points of retina, as well as its average value, varying several parameters in the model. This work demonstrates how anybody with basic knowledge of calculus is able to build physically meaningful models of quite complex biological systems. PMID:24721554

Kotha, Sreevani; Murtomäki, Lasse

2014-07-01

394

Modeling and simulation of the human eye  

Science.gov (United States)

The computational modeling of the human eye has been wide studied for different sectors of the scientific and technological community. One of the main reasons for this increasing interest is the possibility to reproduce eye optic properties by means of computational simulations, becoming possible the development of efficient devices to treat and to correct the problems of the vision. This work explores this aspect still little investigated of the modeling of the visual system, considering a computational sketch that make possible the use of real data in the modeling and simulation of the human visual system. This new approach makes possible the individual inquiry of the optic system, assisting in the construction of new techniques used to infer vital data in medical investigations. Using corneal topography to collect real data from patients, a computational model of cornea is constructed and a set of simulations were build to ensure the correctness of the system and to investigate the effect of corneal abnormalities in retinal image formation, such as Plcido Discs, Point Spread Function, Wave front and the projection of a real image and it's visualization on retina.

Duran, R.; Ventura, L.; Nonato, L.; Bruno, O.

2007-02-01

395

Clinical evaluation of Vitamin A palmitate eye ophthalmic gel combined Ellie eye drops for treatment of eye surface trauma  

Directory of Open Access Journals (Sweden)

Full Text Available AIM: To observe and evaluate clinical effect of the combined use of vitamin A palmitate eye ophthalmic gel and Ellie eye drops for the treatment of various eye surface damage. METHODS:Totally 167 cases of corneal disease were randomly divided into Ellie eye drops treatment group(n=45, vitamin A palmitate eye ophthalmic gel(n=55in treatment group, the combined use group(n=67. Ellie eye drops were used to drop eye every 2 hours a day(daily 6 times. Vitamin A palmitate eye ophthalmic gel treatment group was used every 2 hours a day(daily 6 times, eye drops 1 time before sleeping in the evening. The combined use group was treated according to the above method of two medicines with 5 minutes interval. RESULTS: Cure rate and the total effective rate of vitamin A palmitate eye ophthalmic gel treatment group were 56.4% and 83.6% respectively. Cure rate and the total effective rate of Ellie eye drops group were 66.7% and 88.9% respectively. Cure rate and the total effective rate of combined use group were 83.6% and 97.0% respectively. Alone use of Ellie eye drops in various eye surface damage was more efficient than vitamin A palmitate eye ophthalmic gel. The efficacy of combined use group for the treatment of various eye surface damages was obviously higher than that of the single application group(PCONCLUSION: Ellie eye drops is more effective than vitamin A palmitate eye ophthalmic gel for the treatment of all kinds of ocular surface damage, but the two medicine combined application treatment is much safer and more specific than the alone application.

Dao-Yuan Jiang

2013-06-01

396

A two-step experimental design for a sediment bioassay using growth of the amphipod Hyalella azteca for the test end point  

Energy Technology Data Exchange (ETDEWEB)

The authors designed a sediment bioassay using 25% growth inhibition of Hyalella azteca as the end point. Hyalella azteca exhibits size-specific fecundity, so growth is a surrogate of reproductive production. They investigated density effects on growth to address whether crowding could affect test interpretation; amphipods in 14,000/m{sup 2} exposures were 16 to 20% smaller than those at 7,000/m{sup 2}. Using power analysis, the authors found that 20 to 25 samples are required to determine significance when {alpha} = 0.10 and 1 {minus} {beta} = 0.90. To minimize the need for laboratory resources, they designed a two-step bioassay, which they tested with field-collected sediments. The screening bioassay compared 11 sediments to a reference. Three sediments were toxic, five sediments were nontoxic, and three sediments were possibly toxic. In the confirmatory bioassay, three possibly toxic and two nontoxic samples were reevaluated. Two were toxic, and the remaining four samples were nontoxic. In summary, five sediments were toxic and six sediments were nontoxic. The two-step analysis used minimal laboratory resources but maximized statistical power, where needed, to discriminate growth effects.

Kubitz, J.A.; Giesy, J.P. [Michigan State Univ., East Lansing, MI (United States); Besser, J.M. [Michigan State Univ., East Lansing, MI (United States)]|[National Biological Service, Columbia, MO (United States). Midwest Science Center

1996-10-01

397

Microbial flora of the dog eyes  

Digital Repository Infrastructure Vision for European Research (DRIVER)

The purpose of this investigation was to isolate microbial flora of the normal dog eyes and eyes with clinical signs of external ocular disease. Samples were collected from 46 dog eyes (92 samples). Pathogens were isolated from 58 eye samples of dogs without clinical signs and 34 – from dogs with clinical signs of one or both eyes. Among the isolated pathogens from eyes of dogs without clinical signs were Staphylococcus spp. (55%), Pseudomonas spp. (11.4%) and Corynebacterium spp. (6.8%). A...

Kudirkiene?, Egle?; Z?ilinskas, Henrikas; S?iugz?daite?, Ju?rate?

2006-01-01

398

Ocular iontophoresis of EGP-437 (dexamethasone phosphate in dry eye patients: results of a randomized clinical trial  

Directory of Open Access Journals (Sweden)

Full Text Available Michael A Patane¹, Amy Cohen¹, Stephen From¹, Gail Torkildsen², Donna Welch³, George W Ousler III³¹Eyegate Pharmaceuticals, Inc, Waltham, MA, USA; ²Andover Eye Associates, Andover, MA, USA; ³Ora, Inc, Andover, MA, USAPurpose: To assess safety and efficacy of EGP-437 (dexamethasone phosphate 40 mg/mL [DP] in dry eye patients.Methods: The study employed a prospective, single-center, double-masked design utilizing a Controlled Adverse Environment (CAE. Patients (n = 103 with confirmed signs and symptoms of dry eye syndrome were randomized into 1 of 3 iontophoresis treatment groups: 7.5 mA-min at 2.5 mA (DP 7.5, n = 41; 10.5 mA-min at 3.5 mA (DP 10.5, n = 37; or 10.5 mA-min at 3.5 mA (placebo, n = 25. Three CAE visits and 4 follow-up visits occurred over 3 weeks. Patients meeting enrollment criteria received iontophoresis in both eyes after the second CAE exposure (visit 3 and before the third CAE exposure (visit 5. Primary efficacy endpoints were corneal staining and ocular discomfort. Secondary endpoints included tear film break-up time, ocular protection index (OPI, and symptomatology.Results: The DP 7.5 and DP 10.5 treatment groups showed statistically significant improvements in signs and symptoms of dry eye at various time points; however, the primary endpoints were not achieved. The DP 7.5 treatment group exhibited statistically significant improvements in corneal staining (when comparing the differences between study entry and exit, 3 weeks, P = 0.039, OPI (immediately following the second treatment, P = 0.048 and ocular discomfort at follow-up visits (a week after the first treatment, P = 0.032; 24 hours after the second treatment, P = 0.0032. Treatment-emergent adverse events (AEs were experienced by 87% of patients and were consistent across all treatment groups. Most AEs were mild and no severe AEs were observed.Conclusion: Ocular iontophoresis of EGP-437 demonstrated statistically and clinically significant improvements in signs and symptoms of dry eye syndrome within a CAE model.Keywords: iontophoresis, dry eye, Controlled Adverse Environment (CAE, ocular protection index (OPI

Patane MA

2011-05-01

399

Cyanoacrylate Adhesives in Eye Wounds.  

Science.gov (United States)

Three main sets of experiments are described in this report: (1) tolerance of cyanocacrylate adhesives in rabbit eyes; (2) in vitro tensile strength of corneal stroma-stroma and sclera-silicone rubber adhesive joints; and (3) sealing corneal and choroidal...

M. F. Refojo

1969-01-01

400

Clearing media for the eye.  

Digital Repository Infrastructure Vision for European Research (DRIVER)

Non-ionic radiological contrast media have a high refractive index and are not toxic to living cells. They can be used as clearing media for unfixed ocular tissues. Corneal opacities in the rabbit could be made transparent, on a temporary basis, by soaking the stroma in contrast media, and no ill effects on the eye were noted.

Maurice, D. M.

1987-01-01

 
 
 
 
401

Radiation effects on eye components  

International Nuclear Information System (INIS)

The radiation damage (X-ray, UV light) of the most important components of the vertebrate eye (crystallins and other proteins, hyaluronic acid, vitreous, aqueous humour, ascorbic acid) has been investigated by various methods of physical chemistry. UV absorption and fluorescence spectroscopy as well as circular dichroism unveiled changes of the chromophores/fluorophores of the constituent biopolymers and low-molecular components, together with alterations of helix content and the occurrence of aggregation. Size-exclusion chromatography, analytical ultracentrifugation, densimetry, viscometry and light scattering experiments monitored changes of the global structure of proteins and polysaccharides involved. Electrophoreses allowed conclusions on fragmentation, unfolding and crosslinking. Analytical methods provided information regarding the integrity of groups of special concern (SH, SS) and revealed the existence of stable noxious species (H_2O_2). By means of various measures and additives, manifold modifications of the impact of both ionizing and nonionizing radiation may be achieved. Caused by differences in the primary reactions, eye polymers are protected efficaciously by typical OH radical scavengers against X-irradiation, whereas compounds which exhibit absorption behavior in the UV range turn out to act as potent protectives ('chemical filters') against UV light. A few substances, such as ascorbate, are able to provide protection against both sorts of radiation and are even able to exhibit a slight chemical repair of already damaged particles. The results obtained are of importance for understanding pathological alterations of the eye (loss of transparency, cataractogenesis) and for developing new strategies for protection and repair of eye components. (author)

1998-09-03

402

If I Had - Dry Eyes  

Medline Plus

Full Text Available ... Dr. Penny Asbell, MD, FACS, MBA, discusses what she would do if she had dry eyes. Dr. Asbell is a Professor ... at the Mount Sinai Medical Center. In addition, she is currently on the Board of Directors of ...

403

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

Science.gov (United States)

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

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

2011-01-01

404

Multicentre ISI assignment and calibration of the INR measuring range of a new point-of-care system designed for home monitoring of oral anticoagulation therapy.  

Science.gov (United States)

The new CoaguChek XS system is designed for use in patient selftesting. It is the successor of the current CoaguChek S system. The detection principle is based on the amperometric measurement of the thrombin activity initiated by starting the coagulation cascade using a human recombinant thromboplastin. This study was performed to assign the International SEnsitivity Index (ISI) to the new test according to the WHO guidelines for thromboplastins and plasmas used to control anticoagulant therapy, and to establish the measuring range of the new system. At four study sites a total of 90 samples of normal donors and 291 samples of warfarin-, phenprocoumon- or acenocoumarol-treated patients were included in the study. The ISI value of the new test was assigned against the human recombinant reference thromboplastin rTF/95 at each site using the samples from stabilized patients in the International Normalized Ratio (INR) range between 1.5 and 4.5 only. The new point-of-care system's measuring range between 0.8 and 8 INR was calibrated against the mean INR of rTF/95 and AD149 using polynomial regression. ISIs were (CV of the slope): Site 1: ISI 0.99 (1.1%); Site 2: ISI 1.02 (2.0%); Site 3: ISI 1.03 (1.1%); Site 4: ISI 1.00 (1.4%). All regression lines calculated from patient-only data pass through the normal donor data points. All CVs of the slopes of the orthogonal regression lines are well below 3%, thus fulfilling the requirements of the WHO guidelines. The mean ISI for the new CoaguChek XS PT Test is 1.01. PMID:17479198

Leichsenring, Ingrid; Plesch, Winfried; Unkrig, Volker; Kitchen, Steve; Kitchen, Dianne P; Maclean, Rhona; Dikkeschei, Bert; van den Besselaar, Anton M H P

2007-05-01

405

Children's Eye Injuries: Prevention and Care  

Science.gov (United States)

... dangerous projectile in a crash. First Aid An Eye M.D. (ophthalmologist) , primary care doctor, school nurse or children’s health service should examine the eye as soon as possible, even if the injury ...

406

Prescriptions for Eye Glasses and Contact Lenses  

Science.gov (United States)

... Contact Lenses Related Items The Basics of LASIK Eye Surgery Buying Cosmetic Contact Lenses? Millions of Americans wear ... for the Common Cold The Basics of LASIK Eye Surgery Weight Loss & Fitness Jobs & Making Money Privacy & Identity ...

407

Anesthesia for Children Having Eye Surgery  

Science.gov (United States)

... kinds of anesthesia are available for children having eye surgery? Anesthesia is necessary during all kinds of surgery to reduce or eliminate pain. Eye surgery is no exception. General anesthesia, which puts the ...

408

What Is a Comprehensive Dilated Eye Exam?  

Science.gov (United States)

... of damage and other eye problems, such as diabetic retinopathy or age-related macular degeneration. A dilated eye ... NEI Office of Science Communications, Public Liaison, and Education. Technical questions about this website can be addressed ...

409

Prevent Diabetes Problems: Keep Your Eyes Healthy  

Science.gov (United States)

... eye care professional to check for signs of cataracts and glaucoma . See What other eye problems can ... to people with diabetes? to learn more about cataracts and glaucoma. If you are planning to get ...

410

Dry Eyes and Glaucoma: Double Trouble  

Science.gov (United States)

Dry Eyes and Glaucoma: Double Trouble email Send this article to a friend by filling out the fields below: Your name: Your friend's ... heating and cooling systems. Treating Dry Eye and Glaucoma Usually a combination of treatments is helpful, and ...

411

Simulations of Keratoconus Patient Vision with Optical Eye Modeling  

Science.gov (United States)

Keratoconus (KC) is an eye condition that involves progressive corneal thinning. Pushed by the intraocular pressure, the weakened cornea bulges outward and creates an irregular surface shape. The result is degraded vision that is difficult to correct with regular eye glasses or contact lens. In this study we use the optical lens design software, ZeMax, and patient data including cornea topography and refraction prescription to construct KC eye models. The variation of KC ``cone height'' on the cornea is used to simulate KC progression. The consequent patients' night vision and Snellen letter chart vision at 20 feet are simulated using these anatomically accurate 3-dimensional models. 100 million rays are traced for each image simulation. Animated results illustrate the change of KC visual acuity with the progression of disease. This simulation technique provides a comprehensive tool for medical training and patient consultation/education.

Tan, Bo; Chen, Ying-Ling; Lewis, J. W. L.; Shi, Lei; Wang, Ming

2007-11-01

412

Stereological estimation of eye volume using the Pappus method.  

Science.gov (United States)

The estimation of object volume from rotationally randomised sections relies on an ancient geometrical principle due to the Alexandrian mathematician Pappus. In this paper we describe two studies that make estimates of eye volume using a stereological version of the Pappus principle. The first study uses a design-based version of the Pappus theorem to make estimates of eye volume in Sprague-Dawley rats and the second uses a model-based implementation for estimating eye volume in juvenile Dover sole. In the sole study we compare the estimates of volume with estimates made using the Cavalieri method and show that the Pappus method gives identical volume estimates with a markedly lower coefficient of variation (2.5%) than the Cavalieri method (13.5%). PMID:11422669

Reed, M G; Shanks, E; Beech, D J; Barlow, L; Howard, C V

2001-06-01

413

Factors associated with second eye cataract surgery  

Digital Repository Infrastructure Vision for European Research (DRIVER)

AIMS—To analyse the clinical and sociodemographic characteristics associated with second eye cataract surgery.?METHODS—An observational, longitudinal study of patients scheduled for first eye cataract surgery that did not involve a combined procedure was carried at two teaching hospitals and one non-teaching hospital in Barcelona, Spain. Patients were followed for 2 years after first eye cataract surgery to assess whether and when they had undergone second eye cataract surgery. Cli...

Castells, X.; Alonso, J.; Ribo, C.; Nara, D.; Teixido, A.; Castilla, M.

2000-01-01

414

Impact of dry eye on work productivity  

Directory of Open Access Journals (Sweden)

Full Text Available Masakazu Yamada, Yoshinobu Mizuno, Chika ShigeyasuNational Institute of Sensory Organs, National Hospital Organization Tokyo Medical Center, Tokyo, JapanBackground: The purpose of this study was to evaluate the impact of dry eye on work productivity of office workers, especially in terms of presenteeism.Methods: A total of 396 individuals aged ?20 years (258 men and 138 women, mean age 43.4 ± 13.0 years were recruited through an online survey. Data from 355 responders who did not have missing values were included in the analysis. They were classified into the following four groups according to the diagnostic status and subjective symptoms of dry eye: a definite dry eye group; a marginal dry eye group; a self-reported dry eye group; and a control group. The impact of dry eye on work productivity was evaluated using the Japanese version of the Work Limitations Questionnaire. The cost of work productivity loss associated with dry eye and the economic benefits of providing treatment for dry eye were also assessed.Results: The degree of work performance loss was 5.65% in the definite dry eye group, 4.37% in the marginal dry eye group, 6.06% in the self-reported dry eye group, and 4.27% in the control group. Productivity in the self-reported dry eye group was significantly lower than that in the control group (P < 0.05. The annual cost of work productivity loss associated with dry eye was estimated to be USD 741 per person.Conclusion: Dry eye impairs work performance among office workers, which may lead to a substantial loss to industry. Management of symptoms of dry eye by providing treatment may contribute to improvement in work productivity.Keywords: burden of disease, dry eye, presenteeism, quality of life

Yamada M

2012-10-01

415

Ophthalmic Diagnostics Using Eye Tracking Technology  

Digital Repository Infrastructure Vision for European Research (DRIVER)

Human eyes directly reflect brain activity and cognition. The study of eye movements and gaze patterns can therefore say a lot about the human brain and human behavior. Today eye tracking technology is being used to measure acuity of toddlers, to rehabilitate patients in intensive care, to detect if a person is lying or not, and to understand the cognitive level of a non-verbal person. Current vision testing is mostly based on manual observation and subjective methods. With eye tracking techn...

Aldana Pulido, Rafael

2012-01-01

416

Eyeing the Sky's Water Vapor  

Science.gov (United States)

This image, and many like it, are one way NASA's Phoenix Mars Lander is measuring trace amounts of water vapor in the atmosphere over far-northern Mars. Phoenix's Surface Stereo Imager (SSI) uses solar filters, or filters designed to image the sun, to make these images. The camera is aimed at the sky for long exposures. SSI took this image as a test on June 9, 2008, which was the Phoenix mission's 15th Martian day, or sol, since landing, at 5:20 p.m. local solar time. The camera was pointed about 38 degrees above the horizon. The white dots in the sky are detector dark current that will be removed during image processing and analysis. The Phoenix Mission is led by the University of Arizona, Tucson, on behalf of NASA. Project management of the mission is by NASA's Jet Propulsion Laboratory, Pasadena, Calif. Spacecraft development is by Lockheed Martin Space

2008-01-01

417

Experiencing Light's Properties within Your Own Eye  

Science.gov (United States)

Seeing the reflection, refraction, dispersion, absorption, polarization, and scattering or diffraction of light within your own eye makes these properties of light truly personal. There are practical aspects of these within the eye phenomena, such as eye tracking for computer interfaces. They also offer some intriguing diversions, for example,…

Mauser, Michael

2011-01-01

418

Advances in Eye Tracking in Infancy Research  

Science.gov (United States)

In 2004, McMurray and Aslin edited for "Infancy" a special section on eye tracking. The articles in that special issue revealed the enormous promise of automatic eye tracking with young infants and demonstrated that eye-tracking procedures can provide significant insight into the emergence of cognitive, social, and emotional processing in infancy.…

Oakes, Lisa M.

2012-01-01

419

Eye Gaze in Creative Sign Language  

Science.gov (United States)

This article discusses the role of eye gaze in creative sign language. Because eye gaze conveys various types of linguistic and poetic information, it is an intrinsic part of sign language linguistics in general and of creative signing in particular. We discuss various functions of eye gaze in poetic signing and propose a classification of gaze…

Kaneko, Michiko; Mesch, Johanna

2013-01-01

420

21 CFR 878.4440 - Eye pad.  

Science.gov (United States)

...2009-04-01 2009-04-01 false Eye pad. 878.4440 Section 878...MEDICAL DEVICES GENERAL AND PLASTIC SURGERY DEVICES Surgical Devices § 878.4440 Eye pad. (a) Identification. An eye pad is a device that consists...

2009-04-01

 
 
 
 
421

Clinical light damage to the eye  

International Nuclear Information System (INIS)

This book contains four sections: The Nature of Light and of Light Damage to Biological Tissues; Light Damage to the Eye; Protecting the Eye from Light Damage; and Overview of Light Damage to the Eye. Some of the paper titles are: Ultraviolet-Absorbing Intraocular Lens Implants; Phototoxic Changes in the Retina; Light Damage to the Lens; and Radiation, Light, and Sight

1987-01-01

422

Design support at the front end of the New Service Development (NSD) process :the role of touch-points and service personality in supporting team work and innovation processes  

Digital Repository Infrastructure Vision for European Research (DRIVER)

This thesis explores the first stages of New Service Development, and focuses upon the role that design can play to improve the innovation performance of a development team. The work took a ”research by design” approach, that resulted in the design and evaluation of tools and process support, for two specific areas of service innovation. Firstly, how working with the touch-points of a service can improve innovation performance, and secondly the importance of aligning the customer experien...

Clatworthy, Simon

2013-01-01

423

Color and space through the eyes of the youngest  

Digital Repository Infrastructure Vision for European Research (DRIVER)

In my diploma Color And Space Through The Eyes Of The Youngest I focused on the creative field of spatial design in art education in 3rd grade of primary school. Through artistic tasks that were based on works of an artist and architect Friedenreicha Hundertwasser, I wanted to show that colour is an important element which in relation to spatial design creates interesting and original art works.

Logar, Tatjana

2012-01-01

424

Tolerance analysis of cross-eye jamming systems  

Digital Repository Infrastructure Vision for European Research (DRIVER)

The matching required between the two directions through a retrodirective cross-eye jammer is considered using both the traditional phase-front analysis and an extended analysis. The design parameters to achieve a specified tracking error are derived and an optimal design is proposed. The results for the extended analysis show that the tolerances required to induce large angular errors in a monopulse radar are not as strict as the traditional analysis suggests.

Du Plessis, W. P.; Odendaal, J. W.; Joubert, Johan

2011-01-01

425

Cataractogenesis after Cobalt-60 eye plaque radiotherapy  

International Nuclear Information System (INIS)

This study was designed to estimate the actuarial incidence of typical postirradiation cataracts and to identify prognostic factors related to their development in melanoma-containing eyes treated by Cobalt-60 plaque radiotherapy. A special interest was the impact of calculated radiation dose and dose-rate to the lens. The authors evaluated the actuarial occurrence of post-irradiation cataract in 365 patients with primary posterior uveal melanoma treated by Cobalt-60 plaque radiotherapy between 1976 and 1986. Only 22% (S.E. = 4.6%) of the patients who received a total dose of 6 to 20 Gy at the center of the lens developed a visually significant cataract attributable to the radiation within 5 years after treatment. Using multivariate Cox proportional hazards modeling, the authors identified thickness of the tumor, location of the tumor's anterior margin relative to the equatorward and the ora serrata, and diameter of the eye plaque used as the best combination of covariables for predicting length of time until development of cataract. Surprisingly, the dose of radiation delivered to the lens, which was strongly correlated to all of these covariables, was not a significant predictive factor in multivariate analysis. The results suggest that success of efforts to decrease the occurrence rate of post-irradiation cataracts by better treatment planning might be limited in patients with posterior uveal melanoma. 21 refs., 2 figs., 5 tabs

1993-07-15

426

Comment on 'Perfect drain for the Maxwell fish eye lens'  

CERN Document Server

The non-magnetic loss material has been proposed (2011 New J. Phys. 13 023038) to mimic a passive perfect drain in the Maxwell's fish eye lens (MFL). In this comment, we argue that this passive medium can only be treated as a perfect absorber which can totally absorb all incident radiation without scattering by it, but it cannot mimic a delta function at the image point. As a result, this passive medium cannot help to achieve a perfect focusing in MFL.

Sun, Fei

2012-01-01

427

Local skin and eye lens equivalent odses in interventional neuroradiology  

Digital Repository Infrastructure Vision for European Research (DRIVER)

Purpose  To assess patient skin and eye lens doses in interventional neuroradiology and to assess both stochastic and deterministic radiation risks. Methods  Kerma–area product (P KA) was recorded and skin doses measured using thermoluminescence dosimeters. Estimated dose at interventional reference point (IRP) was compared with measured absorbed doses. Results  The average and maximum fluoroscopy times were 32 and 189 min for coiling and 40 and 144 min for embolisation. The average...

Sandborg, Michael; Rossitti, Sandro; Pettersson, Ha?kan

2010-01-01

428

Visibility of wearable sensors as measured using eye tracking glasses  

Digital Repository Infrastructure Vision for European Research (DRIVER)

Sensor technologies can enable independent living for people with dementia by monitoring their behaviour and identifying points where support may be required. Wearable sensors can provide such support but may constitute a source of stigma for the user if they are perceived as visible and therefore obtrusive. This paper presents an empirical investigation exploring the extent to which wearable sensors are perceived as visible. 23 Participants wore eye tracking glasses, which superimposed the l...

King, Meggan; Hu, Feiyan; Mchugh, Joanna; Murphy, Emma; Newman, Eamonn; Irving, Kate; Smeaton, Alan F.

2013-01-01

429

Cloud point extraction for the determination of lead and cadmium in urine by graphite furnace atomic absorption spectrometry with multivariate optimization using Box-Behnken design  

Energy Technology Data Exchange (ETDEWEB)

Cloud point extraction (CPE) is proposed as a pre-concentration procedure for the determination of Pb and Cd in undigested urine by graphite furnace atomic absorption spectrometry (GF AAS). Aliquots of 0.5 mL urine were acidified with HCl and the chelating agent ammonium O,O-diethyl dithiophosphate (DDTP) was added along with the non-ionic surfactant Triton X-114 at the optimized concentrations. Phase separation was achieved by heating the mixture to 50 deg. C for 15 min. The surfactant-rich phase was analyzed by GF AAS, employing the optimized pyrolysis temperatures of 900 deg. C for Pb and 800 deg. C for Cd, using a graphite tube with a platform treated with 500 {mu}g Ru as permanent modifier. The reagent concentrations for CPE (HCl, DDTP and Triton X-114) were optimized using a Box-Behnken design. The response surfaces and the optimum values were very similar for aqueous solutions and for the urine samples, demonstrating that aqueous standards submitted to CPE could be used for calibration. Detection limits of 40 and 2 ng L{sup -1} for Pb and Cd, respectively, were obtained along with an enhancement factor of 16 for both analytes. Three control urine samples were analyzed using this approach, and good agreement was obtained at a 95% statistical confidence level between the certified and determined values. Five real samples have also been analyzed before and after spiking with Pb and Cd, resulting in recoveries ranging from 97 to 118%.

Maranhao, Tatiane de A; Martendal, Edmar; Borges, Daniel L.G.; Carasek, Eduardo [Departamento de Quimica, Universidade Federal de Santa Catarina, 88040-900, Florianopolis, SC (Brazil); Welz, Bernhard [Departamento de Quimica, Universidade Federal de Santa Catarina, 88040-900, Florianopolis, SC (Brazil); Grupo de Pesquisa em Quimica Analitica, Instituto de Quimica, Universidade Federal da Bahia, 40170-290, Salvador, BA (Brazil); Curtius, Adilson J. [Departamento de Quimica, Universidade Federal de Santa Catarina, 88040-900, Florianopolis, SC (Brazil)], E-mail: curtius@qmc.ufsc.br

2007-09-15

430

Cloud point extraction for the determination of lead and cadmium in urine by graphite furnace atomic absorption spectrometry with multivariate optimization using Box-Behnken design  

International Nuclear Information System (INIS)

Cloud point extraction (CPE) is proposed as a pre-concentration procedure for the determination of Pb and Cd in undigested urine by graphite furnace atomic absorption spectrometry (GF AAS). Aliquots of 0.5 mL urine were acidified with HCl and the chelating agent ammonium O,O-diethyl dithiophosphate (DDTP) was added along with the non-ionic surfactant Triton X-114 at the optimized concentrations. Phase separation was achieved by heating the mixture to 50 deg. C for 15 min. The surfactant-rich phase was analyzed by GF AAS, employing the optimized pyrolysis temperatures of 900 deg. C for Pb and 800 deg. C for Cd, using a graphite tube with a platform treated with 500 ?g Ru as permanent modifier. The reagent concentrations for CPE (HCl, DDTP and Triton X-114) were optimized using a Box-Behnken design. The response surfaces and the optimum values were very similar for aqueous solutions and for the urine samples, demonstrating that aqueous standards submitted to CPE could be used for calibration. Detection limits of 40 and 2 ng L-1 for Pb and Cd, respectively, were obtained along with an enhancement factor of 16 for both analytes. Three control urine samples were analyzed using this approach, and good agreement was obtained at a 95% statistical confidence level between the certified and determined values. Five real samples have also been analyzed before and after spiking with Pb and Cd, resulting in recoveries ranging from 97 to 118%

2007-09-01

431

Cloud point extraction for the determination of lead and cadmium in urine by graphite furnace atomic absorption spectrometry with multivariate optimization using Box Behnken design  

Science.gov (United States)

Cloud point extraction (CPE) is proposed as a pre-concentration procedure for the determination of Pb and Cd in undigested urine by graphite furnace atomic absorption spectrometry (GF AAS). Aliquots of 0.5 mL urine were acidified with HCl and the chelating agent ammonium O,O-diethyl dithiophosphate (DDTP) was added along with the non-ionic surfactant Triton X-114 at the optimized concentrations. Phase separation was achieved by heating the mixture to 50 °C for 15 min. The surfactant-rich phase was analyzed by GF AAS, employing the optimized pyrolysis temperatures of 900 °C for Pb and 800 °C for Cd, using a graphite tube with a platform treated with 500 ?g Ru as permanent modifier. The reagent concentrations for CPE (HCl, DDTP and Triton X-114) were optimized using a Box Behnken design. The response surfaces and the optimum values were very similar for aqueous solutions and for the urine samples, demonstrating that aqueous standards submitted to CPE could be used for calibration. Detection limits of 40 and 2 ng L- 1 for Pb and Cd, respectively, were obtained along with an enhancement factor of 16 for both analytes. Three control urine samples were analyzed using this approach, and good agreement was obtained at a 95% statistical confidence level between the certified and determined values. Five real samples have also been analyzed before and after spiking with Pb and Cd, resulting in recoveries ranging from 97 to 118%.

Maranhão, Tatiane De A.; Martendal, Edmar; Borges, Daniel L. G.; Carasek, Eduardo; Welz, Bernhard; Curtius, Adilson J.

2007-09-01

432

Eye-Hand Coordination in Children with High Functioning Autism and Asperger's Disorder Using a Gap-Overlap Paradigm  

Science.gov (United States)

We investigated eye-hand coordination in children with autism spectrum disorders (ASD) in comparison with age-matched normally developing peers. The eye-hand correlation was measured by putting fixation latencies in relation with pointing and key pressing responses in visual detection tasks where a gap-overlap paradigm was used and compared to…

Crippa, Alessandro; Forti, Sara; Perego, Paolo; Molteni, Massimo

2013-01-01

433

Are 3-D Movies Bad for Your Eyes?  

Medline Plus

Full Text Available ... the Sun Eye Health News Consumer Alerts Are 3-D Movies Bad for Your Eyes? Tweet Eye ... on computer use and your eyes . Children and 3-D Technology Following the lead of Nintendo, several ...

434

Are 3-D Movies Bad for Your Eyes?  

Medline Plus

Full Text Available ... Marijuana for Glaucoma Pregnancy Preventing Eye Injuries Smokers Sports Teenagers Using Eye Makeup Veterans What Is an ... Usage & Eye Strain Maintaining Your Sight with Diabetes Sports and Eye Protection Eyesight Risks for Smokers Veterans & ...

435

Are 3-D Movies Bad for Your Eyes?  

Medline Plus

Full Text Available ... Dry Eye Floaters & Flashes Glaucoma Hyperopia (Farsightedness) Low Vision Myopia (Nearsightedness) Pink Eye (Conjunctivitis) Presbyopia (Aging Eye) ... Symptoms Blurriness Dark Curtain Dark Spots Discharge Double Vision Drooping Eyelid Eye Pain Eyelash Crusting Eyelid Lump ...

436

Are 3-D Movies Bad for Your Eyes?  

Medline Plus

Full Text Available ... 40 to 60 Adults Over 60 Babies & Children Computer Usage Diabetes Diet & Nutrition Eye Screening Guidelines Home ... Topics Preventing Eye Injuries Healthy Eyes During Pregnancy Computer Usage & Eye Strain Maintaining Your Sight with Diabetes ...

437

Focal Points  

Digital Repository Infrastructure Vision for European Research (DRIVER)

This paper gives an overview of the literature on focal points. It starts with reviewing Schelling’s seminal book The Strategy of Conflict.I then discuss the problems that have to be faced when incorporating the notion of focal points in theory of games. Two recent approaches are discussed that deal with focal points. The eductive approach is static and concentrates on how players can use aymmetries in the descriptions of strategies. The evolutive approach is dynamic and focuses in the adap...

Janssen, M. C. W.

1997-01-01

438

Dry Eye: Prevalence and Attributable Risk Factors in a Hospital-Based Population  

Directory of Open Access Journals (Sweden)

Full Text Available Purpose: To study the prevalence of dry eye in a hospital-based population and to evaluate the various risk factors attributable to dry eye. Materials and Methods: In this cross-sectional study, 500 patients above 20 years of age were screened randomly for dry eye. A 13-point questionnaire, Lissamine Green test, Tear film break-up time (TBUT, Schirmer?s test and presence of strands/filaments were used to diagnose dry eye. The diagnosis was made when at least three of the tests were positive. The role of air pollution, sunlight, excessive winds, smoking, drugs and refractive status as dry eye risk factors was assessed. Results: Ninety-two (18.4% patients had dry eye. Dry eye prevalence was maximum in those above 70 years of age (36.1% followed by the age group 31-40 years (20%. It was significantly higher ( P = 0.024 in females (22.8% than in males (14.9%, more common in rural residents (19.6% than in urban (17.5% and highest among farmers/labourers (25.3%. A 2.15 fold increase was found in the odds for dry eye in those exposed to excessive wind, 1.91 fold to sunlight exposure, 1.42 to smoking, 1.38 to air pollution and 2.04 for persons on drugs. Dry eye prevalence was 14% in emmetropes, 16.8% in myopes and 22.9% in hypermetropes. It was 15.6% in those with corrected and 25.3% in those with uncorrected refractive errors. Conclusion: Dry eye is an under-diagnosed ocular disorder. Reduction in the modifiable risk factors of dry eye is essential to reduce its prevalence

Sahai Anshu

2005-01-01

439

Eye Movements in Gaze Interaction  

DEFF Research Database (Denmark)

Gaze as a sole input modality must support complex navigation and selection tasks. Gaze interaction combines specific eye movements and graphic display objects (GDOs). This paper suggests a unifying taxonomy of gaze interaction principles. The taxonomy deals with three types of eye movements: fixations, saccades and smooth pursuits and three types of GDOs: static, dynamic, or absent. This taxonomy is qualified through related research and is the first main contribution of this paper. The second part of the paper offers an experimental exploration of single stroke gaze gestures (SSGG). The main findings suggest (1) that different lengths of SSGG can be used for interaction, (2) that GDOs are not necessary for successful completion, and (3) that SSGG are comparable to dwell time selection.

Møllenbach, Emilie; Hansen, John Paulin

2013-01-01

440

Management of thyroid eye disease  

Energy Technology Data Exchange (ETDEWEB)

Thyroid eye disease (TED) is the most frequent extrathyroidal manifestation of Graves' disease. In most instances it is mild and non-progressive, but in 3%-5% of cases it is severe. Non-severe TED requires only supportive measures, such as eye ointments, sunglasses and prisms. By contrast, severe TED requires aggressive treatment, either medical (high-dose glucocorticoids, orbital radiotherapy) or surgical (orbital decompression). The choice of treatment relies on the assessment of both TED severity and activity. Removal of controllable risk factors, especially cigarette smoking, is important to improve the course and the therapeutic outcome. A coordinated approach to the treatment of hyperthyroidism and TED is also required. Novel promising treatments, to be verified in large series of patients, include somatostatin analogues and cytokine antagonists. (orig.)

Bartalena, Luigi; Tanda, Maria Laura [Department of Endocrinology, University of Insubria, Ospedale di Circolo, Viale Borri, 57, 21100 Varese (Italy); Marcocci, Claudio; Pinchera, Aldo [Department of Endocrinology and Metabolism, University of Pisa, Pisa (Italy)

2002-08-01

 
 
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