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https://www.readbyqxmd.com/read/28231267/accuracy-of-optical-biometry-combined-with-placido-disc-corneal-topography-for-intraocular-lens-power-calculation
#1
Giacomo Savini, Kenneth J Hoffer, Piero Barboni, Nicole Balducci, Domenico Schiano-Lomoriello, Pietro Ducoli
PURPOSE: To investigate the accuracy of a new optical biometer for intraocular lens (IOL) power calculation in eyes undergoing cataract surgery. METHODS: Consecutive eyes of patients undergoing cataract surgery with the same IOL model were enrolled in a prospective cohort study. Axial length (AL) and corneal power were measured with an optical biometer based on optical low-coherence interferometry and Placido-disc corneal topography. IOL power was calculated with the Hoffer Q, Holladay 1 and SRK/T formulas...
2017: PloS One
https://www.readbyqxmd.com/read/28230557/comparison-of-the-conventional-dresden-protocol-and-accelerated-protocol-with-higher-ultraviolet-intensity-in-corneal-collagen-cross-linking-for-keratoconus
#2
Moonjung Choi, Jiwon Kim, Eung Kweon Kim, Kyoung Yul Seo, Tae-Im Kim
PURPOSE: To compare the accelerated corneal cross-linking (CXL) protocol and the conventional Dresden protocol in patients with keratoconus in terms of visual acuity, keratometric values, and topographic parameters. METHODS: Twenty-eight eyes of 25 patients with primary keratoconus were divided into 2 groups; 15 eyes in group 1 received CXL under the standard Dresden protocol (3 mW/cm for 30 min, dose 5.4 J/cm) and 13 eyes in group 2 were treated with the accelerated protocol (30 mW/cm for 3 min 40 s, dose 6...
February 22, 2017: Cornea
https://www.readbyqxmd.com/read/28228410/prediction-of-the-true-iol-position
#3
Sverker Norrby, Rolf Bergman, Nino Hirnschall, Yutaro Nishi, Oliver Findl
PURPOSE: To develop algorithms for preoperative estimation of the true postoperative intraocular lens (IOL) position to be used for IOL power calculation. SETTING: Moorfields Eye Hospital NHS Foundation Trust, London, UK. METHODS: Fifty patients were implanted randomly with a 3-piece IOL model in one eye and a 1-piece model in the other eye. Preoperatively, the IOLMaster was used to determine axial length, anterior chamber depth and mean corneal radius...
February 22, 2017: British Journal of Ophthalmology
https://www.readbyqxmd.com/read/28227791/nonlinear-3-d-simulation-of-high-intensity-focused-ultrasound-therapy-in-the-kidney
#4
Visa Suomi, Jiri Jaros, Bradley Treeby, Robin Cleveland, Visa Suomi, Jiri Jaros, Bradley Treeby, Robin Cleveland, Jiri Jaros, Bradley Treeby, Robin Cleveland, Visa Suomi
Kidney cancer is a severe disease which can be treated non-invasively using high-intensity focused ultrasound (HIFU) therapy. However, tissue in front of the transducer and the deep location of kidney can cause significant losses to the efficiency of the treatment. The effect of attenuation, refraction and reflection due to different tissue types on HIFU therapy of the kidney was studied using a nonlinear ultrasound simulation model. The geometry of the tissue was derived from a computed tomography (CT) dataset of a patient which had been segmented for water, bone, soft tissue, fat and kidney...
August 2016: Conference Proceedings: Annual International Conference of the IEEE Engineering in Medicine and Biology Society
https://www.readbyqxmd.com/read/28226932/novel-refractive-index-biosensing-of-microcontact-printed-molecules-on-lithium-niobate
#5
Nikhil Bhalla, Shivani Sathish, Amy Q Shen, Nikhil Bhalla, Shivani Sathish, Amy Q Shen, Shivani Sathish, Amy Q Shen, Nikhil Bhalla
This work demonstrates, for the first time, the use of lithium niobate as a biosensor that detects local refractive index changes triggered by the presence of biomolecules on its surface. The sensitivity of the sensor was found to be 242±16 nm/RIU. As a case study, we immobilized proteins (IgG antibodies) using micro-contact printing to demonstrate sensing capabilities of the device. The validated proof of concept lays a foundation for developing lithium niobate based novel optical biosensors.
August 2016: Conference Proceedings: Annual International Conference of the IEEE Engineering in Medicine and Biology Society
https://www.readbyqxmd.com/read/28226407/relationship-between-functional-and-structural-retinal-changes-in-myopic-eyes
#6
Zafer Fahiem Ismael, Amany Abd El-Fattah El-Shazly, Yousra Ahmed Farweez, Marwa Mahmoud Mohammed Osman
BACKGROUND: The aim of this study was to investigate the retinal structure in different grades of myopia and correlate it with the functional changes detected with multifocal electroretinogram (mf-ERG) and try to show the most important determining factors. METHODS: The study included 80 participants divided into four groups according to their spherical equivalent refractive error, namely, emmetropia (within ± 0.50 D), mild myopia group (greater than -0.50 to -3...
February 22, 2017: Clinical & Experimental Optometry: Journal of the Australian Optometrical Association
https://www.readbyqxmd.com/read/28225372/spherical-soft-contact-lens-designs-and-peripheral-defocus-in-myopic-eyes
#7
Kelly E Moore, Julia S Benoit, David A Berntsen
PURPOSE: Peripheral retinal defocus has been implicated in myopia progression. The effect of commercially available spherical soft contact lenses (SCLs) on peripheral defocus of adult myopic eyes was investigated. METHODS: Twenty-five young adults with spherical equivalent (SE) refractions between -0.50D and -6.00D were enrolled. Cycloplegic autorefraction (right eye) was measured centrally and ±20°, ±30°, and ±40° from the line of sight along the horizontal meridian using an autorefractor...
March 2017: Optometry and Vision Science: Official Publication of the American Academy of Optometry
https://www.readbyqxmd.com/read/28225100/hybrid-plasmonic-photonic-whispering-gallery-mode-resonators-for-sensing-a-critical-review
#8
REVIEW
Angelo Bozzola, Sara Perotto, Francesco De Angelis
In this review we present the state of the art and the most recent advances in the field of optical sensing with hybrid plasmonic-photonic whispering gallery mode (WGM) resonators. After a brief introduction on the basic physics behind photonic WGM resonators and localized surface plasmon (LSP) nanostructures, we analyze the different types of optical sensors specifically designed for bulk refractive index sensing, molecular binding and single object detection. We point out the physical and technological key points of the different approaches proposed in the literature, and we systematically compare hybrid sensors and purely photonic WGM sensors...
February 22, 2017: Analyst
https://www.readbyqxmd.com/read/28225004/nonreciprocal-nonlinear-wave-scattering-by-loss-compensated-active-hyperbolic-structures
#9
O V Shramkova, G P Tsironis
The combinatorial frequency generation (CFG) in active periodic semiconductor-dielectric structures has been explored through illumination by a pair of pump waves with dissimilar frequencies and incidence angles. We study the influence of gain on linear refraction properties of the stack and on the efficiency of the mixing processes by the system with the resistive character of nonlinearity. We demonstrate that the introduction of gain dielectric material inside the stack not only compensates for losses caused by the collisions of the electrons in semiconductor media but also improves the efficiency of the CFG...
February 22, 2017: Scientific Reports
https://www.readbyqxmd.com/read/28222711/pseudophakic-ametropia-management-with-toric-implantable-collamer-lens-with-a-central-hole-case-report
#10
Xun Chen, Xiaoying Wang, Xingtao Zhou
BACKGROUND: To report the clinical outcomes of correcting pseudophakic ametropia using toric implantable collamer lens with a 360 um central hole (TICL V4c). CASE PRESENTATION: The right eye of a 22-year-old male patient developed high myopia after unilateral phacoemulsification and intraocular lens (IOL) implantation following traumatic cataract 16 years ago. The manifest refraction was -11.50 DS/-2.50 DC × 175 with an uncorrected distance visual acuity (UDVA) of 20/2000 and a corrected distance visual acuity (CDVA) of 20/20...
February 21, 2017: BMC Ophthalmology
https://www.readbyqxmd.com/read/28222490/the-prevalence-of-convergence-insufficiency-in-iran-a-population-based-study
#11
Hassan Hashemi, Payam Nabovati, Mehdi Khabazkhoob, Hadi Ostadimoghaddam, Asgar Doostdar, Ehsan Shiralivand, Abbasali Yekta
PURPOSE: The aim was to determine the prevalence of convergence insufficiency and its relationship with age, gender and refractive error in a population-based study. METHODS: In this cross-sectional study, all residents over one year old in Mashhad city, in the north east of Iran, were sampled through random stratified cluster sampling. After selecting samples and their participation in the study, they all had eye examinations including the measurement of visual acuity, refraction, binocular vision assessment, including cover test, measurement of near point of convergence and fusional vergences and finally, slitlamp biomicroscopy...
February 21, 2017: Clinical & Experimental Optometry: Journal of the Australian Optometrical Association
https://www.readbyqxmd.com/read/28221389/optical-electrical-and-magnetic-properties-of-lanthanum-strontium-manganite-la1-xsrxmno3-synthesized-through-the-citrate-combustion-method
#12
Ali Omar Turky, Mohamed Mohamed Rashad, Ali Mostafa Hassan, Elsayed M Elnaggar, Mikhael Bechelany
Generally, strontium-doped lanthanum manganites (LSM) are materials connected ordinarily as cathodes in the solid oxide fuel cell (SOFC). In this study, the structural, optical, electrical and magnetic properties of La1-xSrxMnO3 (x = 0.2, 0.5, 0.8) synthesized using an organic acid precursor strategy were investigated, based on using citric acid as a fuel. Evidently, the results disclosed that a pure single monoclinic LSM phase was obtained from the thermally treated precursors annealed at 1000 °C with an annealing time of 2 h...
February 21, 2017: Physical Chemistry Chemical Physics: PCCP
https://www.readbyqxmd.com/read/28221327/changes-in-the-lipidomic-profile-of-aqueous-humor-in-open-angle-glaucoma
#13
Javier Cabrerizo, Javier A Urcola, Elena Vecino
PURPOSE: To identify and determine differences in lipid profiles of aqueous humor (AH) in patients with open-angle glaucoma (OAG). MATERIALS AND METHODS: The lipidomic profile of 10 samples of AH of patients with OAG and 10 controls was analyzed. Patients with a history of anterior segment surgery, anterior segment pathology, or intraocular injections were excluded. Topical ocular medications within the last 6 months were reported. AH was obtained during the first step of nonperforating deep sclerotomy in OAG patients and during refractive lensectomy in controls...
February 17, 2017: Journal of Glaucoma
https://www.readbyqxmd.com/read/28220865/symmetry-breaking-of-counter-propagating-light-in-a-nonlinear-resonator
#14
Leonardo Del Bino, Jonathan M Silver, Sarah L Stebbings, Pascal Del'Haye
Spontaneous symmetry breaking is a concept of fundamental importance in many areas of physics, underpinning such diverse phenomena as ferromagnetism, superconductivity, superfluidity and the Higgs mechanism. Here we demonstrate nonreciprocity and spontaneous symmetry breaking between counter-propagating light in dielectric microresonators. The symmetry breaking corresponds to a resonance frequency splitting that allows only one of two counter-propagating (but otherwise identical) states of light to circulate in the resonator...
February 21, 2017: Scientific Reports
https://www.readbyqxmd.com/read/28220761/electrically-tunable-terahertz-polarization-converter-based-on-overcoupled-metal-isolator-metal-metamaterials-infiltrated-with-liquid-crystals
#15
Borislav Vasić, Dimitrios C Zografopoulos, Goran Isić, Romeo Beccherelli, Radoš Gajić
Large birefringence and its electrical modulation by means of Fréedericksz transition makes nematic liquid crystals (LCs) a promising platform for tunable terahertz (THz) devices. The thickness of standard LC cells is in the order of the wavelength, requiring high driving voltages and allowing only a very slow modulation at THz frequencies. Here, we first present the concept of overcoupled metal-isolator-metal (MIM) cavities that allow for achieving simultaneously both very high phase difference between orthogonal electric field components and large reflectance...
February 21, 2017: Nanotechnology
https://www.readbyqxmd.com/read/28220252/long-term-surgical-outcomes-of-the-inverted-internal-limiting-membrane-flap-technique-in-highly-myopic-macular-hole-retinal-detachment
#16
Taiga Kinoshita, Yasutaka Onoda, Takatoshi Maeno
BACKGROUND: Pars plana vitrectomy (PPV) procedures are used for the surgical treatment of macular hole retinal detachment (MHRD) associated with high myopia. Re-detachment of the retina has been reported in MHRD associated with high myopia. Our aim was to evaluate the 1-year outcomes of vitrectomy, performed using an inverted internal limiting membrane (ILM) flap technique with gas tamponade, in five cases of MHRD associated with high myopia. METHODS: We performed a retrospective review of medical records of five consecutive cases of highly myopic MHRD...
February 20, 2017: Graefe's Archive for Clinical and Experimental Ophthalmology
https://www.readbyqxmd.com/read/28220001/refractive-index-sensing-with-fano-resonances-in-silicon-oligomers
#17
Katie E Chong, Henry W Orton, Isabelle Staude, Manuel Decker, Andrey E Miroshnichenko, Igal Brener, Yuri S Kivshar, Dragomir N Neshev
We demonstrate experimentally refractive index sensing with localized Fano resonances in silicon oligomers, consisting of six disks surrounding a central one of slightly different diameter. Owing to the low absorption and narrow Fano-resonant spectral features appearing as a result of the interference of the modes of the outer and the central disks, we demonstrate refractive index sensitivity of more than 150 nm RIU(-1) with a figure of merit of 3.8.This article is part of the themed issue 'New horizons for nanophotonics'...
March 28, 2017: Philosophical Transactions. Series A, Mathematical, Physical, and Engineering Sciences
https://www.readbyqxmd.com/read/28220000/suppression-of-scattering-for-small-dielectric-particles-anapole-mode-and-invisibility
#18
Boris Luk'yanchuk, Ramón Paniagua-Domínguez, Arseniy I Kuznetsov, Andrey E Miroshnichenko, Yuri S Kivshar
We reveal that an isotropic, homogeneous, subwavelength particle with high refractive index can produce ultra-small total scattering. This effect, which follows from the inhibition of the electric dipole radiation, can be identified as a Fano resonance in the scattering efficiency and is associated with the excitation of an anapole mode in the particle. This anapole mode is non-radiative and emerges from the destructive interference of electric and toroidal dipoles. The invisibility effect could be useful for the design of highly transparent optical materials...
March 28, 2017: Philosophical Transactions. Series A, Mathematical, Physical, and Engineering Sciences
https://www.readbyqxmd.com/read/28219997/phase-resolved-pulse-propagation-through-metallic-photonic-crystal-slabs-plasmonic-slow-light
#19
Anja Schönhardt, Dietmar Nau, Christina Bauer, André Christ, Hedi Gräbeldinger, Harald Giessen
We characterized the electromagnetic field of ultra-short laser pulses after propagation through metallic photonic crystal structures featuring photonic and plasmonic resonances. The complete pulse information, i.e. the envelope and phase of the electromagnetic field, was measured using the technique of cross-correlation frequency resolved optical gating. In good agreement, measurements and scattering matrix simulations show a dispersive behaviour of the spectral phase at the position of the resonances. Asymmetric Fano-type resonances go along with asymmetric phase characteristics...
March 28, 2017: Philosophical Transactions. Series A, Mathematical, Physical, and Engineering Sciences
https://www.readbyqxmd.com/read/28219954/mycolactone-reveals-substrate-driven-complexity-of-sec61-dependent-transmembrane-protein-biogenesis
#20
Michael McKenna, Rachel E Simmonds, Stephen High
Mycolactone is the exotoxin virulence factor produced by Mycobacterium ulcerans, the pathogen responsible for Buruli ulcer. The skin lesions and immunosuppression characteristic of this disease result from the action of mycolactone, which targets the Sec61 complex and inhibits the co-translational translocation of secretory proteins into the endoplasmic reticulum. In this study, we investigate the effect of mycolactone on the Sec61-dependent biogenesis of different classes of transmembrane protein (TMP). Our data suggest that the effect of mycolactone on TMP biogenesis depends on how the nascent chain initially engages the Sec61 complex...
February 20, 2017: Journal of Cell Science
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