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https://www.readbyqxmd.com/read/27915322/ocular-morbidity-associated-with-retinopathy-of-prematurity-in-treated-and-untreated-eyes-a-review-of-the-literature-and-data-from-a-tertiary-eye-care-center-in-southern-india
#1
Perumalsamy Vijayalakshmi, Tulika Kara, Clare Gilbert
Retinopathy of prematurity (ROP) is an emerging cause of childhood blindness in low- and middle-income countries. We review the magnitude, causes, prevention and treatment of visual impairment caused by ROP over a time span. A review of literature on short and long term structural and functional outcomes of ROP was conducted through PubMed search primarily focusing on studies published during the last decade. Additionally, we have shared data from our institute located in Southern India. Visual Impairment in ROP-treated children ranged from 4...
November 7, 2016: Indian Pediatrics
https://www.readbyqxmd.com/read/27914659/corneal-collagen-cross-linking-a-review-of-its-clinical-applications
#2
K Balparda, M J Maldonado
OBJECTIVE: To perform a literature review of the current clinical applications of corneal collagen cross-linking. METHODS: An exhaustive literature search was made, including the main biomedical databases, and encompassing all years since the introduction of cross-linking in ophthalmology practice. RESULTS: Corneal collagen cross-linking using UVA irradiation and riboflavin is a surgical technique that is currently being optimised, and is supported by a good amount of pre-clinical and clinical studies...
November 30, 2016: Archivos de la Sociedad Española de Oftalmología
https://www.readbyqxmd.com/read/27914403/acoustic-attenuation-imaging-of-tissue-bulk-properties-with-a-priori-information
#3
Fong Ming Hooi, Oliver Kripfgans, Paul L Carson
Attenuation of ultrasound waves traversing a medium is not only a result of absorption and scattering within a given tissue, but also of coherent scattering, including diffraction, refraction, and reflection of the acoustic wave at tissue boundaries. This leads to edge enhancement and other artifacts in most reconstruction algorithms, other than 3D wave migration with currently impractical, implementations. The presented approach accounts for energy loss at tissue boundaries by normalizing data based on variable sound speed, and potential density, of the medium using a k-space wave solver...
September 2016: Journal of the Acoustical Society of America
https://www.readbyqxmd.com/read/27914387/investigation-of-horizontal-refraction-on-florida-straits-continental-shelf-using-a-three-dimensional-gaussian-ray-bundling-model
#4
Sean M Reilly, Gopu R Potty, David Thibaudeau
Acoustic transmission loss measurements from the calibration operations (CALOPS) experiment for the Shallow Water Array Performance (SWAP) program included horizontally refracted returns that were as much as 30° away from the true bearing between source and receiver. In many cases, the in-shore refracted path was 20 dB stronger than the true bearing path. In this study CALOPS transmission loss measurements at 415 Hz are compared to predictions from a three-dimensional Gaussian ray bundling model. The geoacoustic model that provides good model-data comparison is consistent with the geologic and sediment core data collected at the location but differs slightly from the bottom model used at lower frequencies (206 and 52...
September 2016: Journal of the Acoustical Society of America
https://www.readbyqxmd.com/read/27914378/toward-ocean-attenuation-tomography-determining-acoustic-volume-attenuation-coefficients-in-seawater-using-eigenray-amplitudes
#5
J D Tippmann, J Sarkar, C M A Verlinden, W S Hodgkiss, W A Kuperman
A deep-water experiment in the Pacific made in situ measurements of the volume attenuation coefficients of sea water in the mid-frequency range. The frequency, temperature, salinity, pH, and pressure dependent seawater attenuation coefficients were determined using a vertical line array that received and identified over 2000 unique paths from 1200 mid-frequency 3-9 kHz LFM source transmissions at a convergence zone range and depth up to 400 m. The results show no change in attenuation coefficients in this band compared to estimates from 30-year-old models previously determined from a combination of long-range ocean acoustic and laboratory experiments...
September 2016: Journal of the Acoustical Society of America
https://www.readbyqxmd.com/read/27913863/-multifocal-intraocular-lens-miol-surgery-in-young-non-presbyopic-ametropes-reasonable-and-safe
#6
A Frings, J Steinberg, S J Linke, V Druchkiv, T Katz
BACKGROUND: Refractive lens exchange and implantation of a multifocal intraocular lens (MIOL) is mainly advised for ametropes with presbyopia. Non-presbyopic young ametropes who wish spectacle-independence are usually treated with corneal refractive surgery or phakic lenses. OBJECTIVES: This retrospective case series aimed to analyse the refractive and subjective satisfaction outcome after MIOL surgery in both eyes of non-presbyopic ametropes where other treatment options were not possible...
December 2, 2016: Der Ophthalmologe: Zeitschrift der Deutschen Ophthalmologischen Gesellschaft
https://www.readbyqxmd.com/read/27912115/self-assembled-hemispherical-nanowell-arrays-for-superhydrophobic-antireflection-coatings
#7
Cheng-Yen Lin, Kun-Yi Andrew Lin, Ting-Wei Yang, Ying-Chu Chen, Hongta Yang
The present study reports an inexpensive and simple bottom-up technology for fabricating superhydrophobic antireflection coatings with highly ordered hemispherical nanowell structures, which are assembled by a scalable Langmuir-Blodgett technology. The subwavelength gratings lead to a gradual change in the effective refractive index, substantially suppressing specular reflection over the entire visible wavelength range. After surface modification with fluorinated silane, the resulting nanowell arrays exhibit superhydrophobic surface with high static water contact angle (154°) and low water contact angle hysteresis (7°)...
November 21, 2016: Journal of Colloid and Interface Science
https://www.readbyqxmd.com/read/27911432/-eye-lid-hygiene-in-chronic-allergic-blepharoconjunctivitis-patients-before-laser-refractive-surgery
#8
S V Yanchenko, A V Malyshev, S N Sakhnov, N V Fedotova, O Yu Orekhova
AIM: To evaluate the effectiveness of eyelid hygiene in patients with chronic allergic blepharoconjunctivitis (ABC) as a part of their preparation for laser refractive surgery. MATERIAL AND METHODS: The study involved 32 patients (12 males and 20 females aged 25-42 years) with refractive errors, namely, compound myopic astigmatism (23 patients) and hyperopic astigmatism (9 patients) suffering from chronic ABC and secondary dry eye syndrome (DES). All the patients initially received a standard treatment for ABC and DES, that is olopatodin hydrochloride instillations - 1 mg/ml 2 times daily, preservative-free hyaluronic acid preparation - 1 mg/ml 3 times daily, and polyacrylic acid and dexpanthenol gel at night for one month...
2016: Vestnik Oftalmologii
https://www.readbyqxmd.com/read/27911425/-biometric-parameters-of-vitrectomized-eyes
#9
S V Asatryan, V K Surguch, S I Kharlap, T A Shchegoleva
AIM: To analyze changes in various biometric parameters after vitrectomy. MATERIAL AND METHODS: A total of 50 patients (50 eyes) were followed up. All of them underwent vitrectomy for idiopathic epiretinal fibrosis and macular hole. In addition to the standard ophthalmic examination, we performed a combined ultrasound study and ultrasound biomicroscopy before and after the surgery (at 2-3 weeks and 6 months). Variation statistics was applied to assess the results using the SPSS Statistica 20 software...
2016: Vestnik Oftalmologii
https://www.readbyqxmd.com/read/27911420/-role-of-immunological-factors-in-the-development-of-myopic-choroidal-neovascularization
#10
A G Shchuko, N V Zaitseva, T N Yur'eva, E R Chernykh, I M Mikhalevich, A V Grigor'eva
AIM: To study the concentration of cytokines in the aqueous humor of the anterior chamber in patients with myopic choroidal neovascularization (mCNV) and to compare the results to their ophthalmic status. MATERIAL AND METHODS: A total of 19 patients (19 eyes) with mCNV treated with intravitreal ranibizumab were included in the study. The control group consisted of 15 patients (15 eyes) with myopia who had cataract surgery. Age, sex, and refractive error distribution were similar to that in the study group...
2016: Vestnik Oftalmologii
https://www.readbyqxmd.com/read/27911101/in-vivo-and-ex-vivo-evaluation-of-inflammation-and-apoptosis-induced-after-smile-procedures-for-different-refractive-error-range
#11
Leonardo Mastropasqua, Roberta Calienno, Claudia Curcio, Rodolfo Mastropasqua, Mario Nubile, Niccolò Salgari, Manuela Lanzini
PURPOSE: To detect corneal inflammation and apoptosis induced after small incision lenticule extraction (SMILE) at different refractive corrections for moderate to high values of myopia. METHODS: Fifty patients (50 eyes) suffering from medium to high myopia (spherical equivalent refraction from -3.75 to -10.00 diopters (D) with refractive astigmatism under -0.75 D) underwent SMILE in order to correct myopic error. In vivo evaluation was done by corneal confocal microscopy (IVCM) and ex vivo by immunohistochemistry...
December 2, 2016: Current Eye Research
https://www.readbyqxmd.com/read/27910958/switchable-3d-optofluidic-y-branch-waveguides-tuned-by-dean-flows
#12
L Li, X Q Zhu, L Liang, Y F Zuo, Y S Xu, Y Yang, Y J Yuan, Q Q Huang
Optical branch waveguides are one of the most important optical elements and have been widely exploited for optical communication systems. However, prevailing devices are typically solid and have limit in tunability. Liquid optical devices have attracted more interest for the advantage of tunability of liquid media, but their signals suffer serious leakage if the refractive index (RI) of liquid is smaller than that of solid channels. This paper demonstrates the tunable three-dimensional (3D) optofluidic Y-branch waveguides in plannar microchannels by simply introducing Dean flow...
December 2, 2016: Scientific Reports
https://www.readbyqxmd.com/read/27910668/compact-and-lightweight-support-platform-with-electromagnetic-disturbance-elimination-for-interferometer-on-reversed-field-pinch-keda-torus-experiment
#13
Wenzhe Mao, Peng Yuan, Jian Zheng, Weixing Ding, Hong Li, Tao Lan, Adi Liu, Wandong Liu, Jinlin Xie
A compact and lightweight support platform has been used as a holder for the interferometer system on the Keda Torus eXperiment (KTX), which is a reversed field pinch device. The vibration caused by the interaction between the time-varying magnetic field and the induced current driven in the metal optical components has been measured and, following comparison with the mechanical vibration of the KTX device and the refraction effect of the ambient turbulent air flow, has been identified as the primary vibration source in this case...
November 2016: Review of Scientific Instruments
https://www.readbyqxmd.com/read/27910486/a-high-spatio-temporal-resolution-optical-pyrometer-at-the-orion-laser-facility
#14
Emma Floyd, Edward T Gumbrell, Jim Fyrth, James D Luis, Jonathan W Skidmore, Siddharth Patankar, Samuel Giltrap, Roland Smith
A streaked pyrometer has been designed to measure the temperature of ≈100 μm diameter heated targets in the warm dense matter region. The diagnostic has picosecond time resolution. Spatial resolution is limited by the streak camera to 4 μm in one dimension; the imaging system has superior resolution of 1 μm. High light collection efficiency means that the diagnostic can transmit a measurable quantity of thermal emission at temperatures as low as 1 eV to the detector. This is achieved through the use of an f/1...
November 2016: Review of Scientific Instruments
https://www.readbyqxmd.com/read/27910444/synthetic-diagnostics-platform-for-fusion-plasmas-invited
#15
L Shi, E J Valeo, B J Tobias, G J Kramer, L Hausammann, W M Tang, M Chen
A Synthetic Diagnostics Platform (SDP) for fusion plasmas has been developed which provides state of the art synthetic reflectometry, beam emission spectroscopy, and Electron Cyclotron Emission (ECE) diagnostics. Interfaces to the plasma simulation codes GTC, XGC-1, GTS, and M3D-C(1) are provided, enabling detailed validation of these codes. In this paper, we give an overview of SDP's capabilities, and introduce the synthetic diagnostic modules. A recently developed synthetic ECE Imaging module which self-consistently includes refraction, diffraction, emission, and absorption effects is discussed in detail...
November 2016: Review of Scientific Instruments
https://www.readbyqxmd.com/read/27910439/talbot-lau-x-ray-deflectometer-electron-density-diagnostic-for-laser-and-pulsed-power-high-energy-density-plasma-experiments-invited
#16
M P Valdivia, D Stutman, C Stoeckl, C Mileham, I A Begishev, W Theobald, J Bromage, S P Regan, S R Klein, G Muñoz-Cordovez, M Vescovi, V Valenzuela-Villaseca, F Veloso
Talbot-Lau X-ray deflectometry (TXD) has been developed as an electron density diagnostic for High Energy Density (HED) plasmas. The technique can deliver x-ray refraction, attenuation, elemental composition, and scatter information from a single Moiré image. An 8 keV Talbot-Lau interferometer was deployed using laser and x-pinch backlighters. Grating survival and electron density mapping were demonstrated for 25-29 J, 8-30 ps laser pulses using copper foil targets. Moiré pattern formation and grating survival were also observed using a copper x-pinch driven at 400 kA, ∼1 kA/ns...
November 2016: Review of Scientific Instruments
https://www.readbyqxmd.com/read/27910378/development-and-characterization-of-an-interferometer-for-calorimeter-based-absorbed-dose-to-water-measurements-in-a-medical-linear-accelerator
#17
Everardo Flores-Martinez, Martha J Malin, Larry A DeWerd
The quantity of relevance for external beam radiotherapy is absorbed dose to water (ADW). An interferometer was built, characterized, and tested to measure ADW within the dose range of interest for external beam radiotherapy using the temperature dependence of the refractive index of water. The interferometer was used to measure radiation-induced phase shifts of a laser beam passing through a (10 × 10 × 10) cm(3) water-filled glass phantom, irradiated with a 6 MV photon beam from a medical linear accelerator...
November 2016: Review of Scientific Instruments
https://www.readbyqxmd.com/read/27910295/combined-application-of-prophylactic-corneal-cross-linking-and-laser-in-situ-keratomileusis-a-review-of-literature
#18
REVIEW
Tommy C Y Chan, Alex L K Ng, Karen K W Chan, George P M Cheng, Ian Y H Wong, Vishal Jhanji
Laser in-situ keratomileusis (LASIK) is safe and effective laser refractive procedures in treating refractive errors. However, regression of treatment and iatrogenic keratectasia remain to be a major concern, especially in treating thin cornea with high ametropia. Collagen cross-linking (CXL) is an effective method in stopping keratoconus progression through increasing the biomechanical strength of the cornea. Adjuvant cross-linking to refractive procedures can theoretically help prevent regression and reduce the risk of keratectasia development by increasing the mechanical stability of cornea...
December 2, 2016: Acta Ophthalmologica
https://www.readbyqxmd.com/read/27910072/enhancing-surface-plasmon-resonance-detection-using-nanostructured-au-chips
#19
Ivan Indutnyi, Yuriy Ushenin, Dirk Hegemann, Marianne Vandenbossche, Victor Myn'ko, Mariia Lukaniuk, Petro Shepeliavyi, Andrii Korchovyi, Roman Khrystosenko
The increase of the sensitivity of surface plasmon resonance (SPR) refractometers was studied experimentally by forming a periodic relief in the form of a grating with submicron period on the surface of the Au-coated chip. Periodic reliefs of different depths and spatial frequency were formed on the Au film surface using interference lithography and vacuum chalcogenide photoresists. Spatial frequencies of the grating were selected close to the conditions of Bragg reflection of plasmons for the working wavelength of the SPR refractometer and the used environment (solution of glycerol in water)...
December 2016: Nanoscale Research Letters
https://www.readbyqxmd.com/read/27908051/internal-tides-and-deep-diel-fades-in-acoustic-intensity
#20
Andrew W White, Frank S Henyey, Rex K Andrew, James A Mercer, Peter F Worcester, Matthew A Dzieciuch, John A Colosi
A mechanism is presented by which the observed acoustic intensity is made to vary due to changes in the acoustic path that are caused by internal-tide vertical fluid displacements. The position in range and depth of large-scale caustic structure is determined by the background sound-speed profile. Internal tides cause a deformation of the background profile, changing the positions of the caustic structures-which can introduce intensity changes at a distant receiver. Gradual fades in the acoustic intensity occurring over timescales similar to those of the tides were measured during a low-frequency (284-Hz) acoustic scattering experiment in the Philippine Sea in 2009 [White et al...
November 2016: Journal of the Acoustical Society of America
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