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https://www.readbyqxmd.com/read/28222490/the-prevalence-of-convergence-insufficiency-in-iran-a-population-based-study
#1
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
#2
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
#3
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
#4
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
#5
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
#6
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
#7
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
#8
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
#9
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
#10
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
https://www.readbyqxmd.com/read/28218302/nonlinear-infrared-spectroscopy-free-from-spectral-selection
#11
Anna Paterova, Shaun Lung, Dmitry A Kalashnikov, Leonid A Krivitsky
Infrared (IR) spectroscopy is an indispensable tool for many practical applications including material analysis and sensing. Existing IR spectroscopy techniques face challenges related to the inferior performance and the high cost of IR-grade components. Here, we develop a new method, which allows studying properties of materials in the IR range using only visible light optics and detectors. It is based on the nonlinear interference of entangled photons, generated via Spontaneous Parametric Down Conversion (SPDC)...
February 20, 2017: Scientific Reports
https://www.readbyqxmd.com/read/28218219/reduced-macular-vascular-density-in-myopic-eyes
#12
Hua Fan, Hao-Yu Chen, Hong-Jie Ma, Zheng Chang, Hai-Quan Yin, Danny Siu-Chun Ng, Carol Y Cheung, Shan Hu, Xiang Xiang, Shi-Bo Tang, Shuang-Nong Li
BACKGROUND: Morphological changes of the vasculature system in patients with myopia have been observed by Doppler ultrasound and fundus fluorescein angiography (FFA); however, these studies have limitations. Doppler ultrasound provides low-resolution images which are mainly obtained from visualized large vessels, and FFA is an invasive examination. Optic coherence tomography (OCT) angiography is a noninvasive, high-resolution measurement for vascular density. The purpose of this study was to investigate the change of vascular density in myopic eyes using OCT angiography...
2017: Chinese Medical Journal
https://www.readbyqxmd.com/read/28217716/electromagnetic-confinement-via-spin-orbit-interaction-in-anisotropic-dielectrics
#13
Alessandro Alberucci, Chandroth P Jisha, Lorenzo Marrucci, Gaetano Assanto
We investigate electromagnetic propagation in uniaxial dielectrics with a transversely varying orientation of the optic axis, the latter staying orthogonal everywhere in the propagation direction. In such a geometry, the field experiences no refractive index gradients, yet it acquires a transversely modulated Pancharatnam-Berry phase, that is, a geometric phase originating from a spin-orbit interaction. We show that the periodic evolution of the geometric phase versus propagation gives rise to a longitudinally invariant effective potential...
December 21, 2016: ACS Photonics
https://www.readbyqxmd.com/read/28216901/technological-evaluation-of-emulsions-containing-the-volatile-oil-from-leaves-of-plectranthus-amboinicus-lour
#14
Pablo Queiroz Lopes, Fabíola Bernardo Carneiro, Ana Letícia Braz de Sousa, Sócrates Golziodo Santos, Elquio Eleamen Oliveira, Luiz Alberto Lira Soares
BACKGROUND: Plectranthus amboinicus Lour is a species which is widespread throughout tropical countries where it is widely used against respiratory tract disorders such as bronchodilator, antitussive, and expectorant conditions. OBJECTIVE: This study aims to characterize the essential oil of P. amboinicus (PaEO) and produce and evaluate emulsions containing PaEO. MATERIALS AND METHODS: The essential oil was characterized by physical-chemical analyses for density, refractive index, 90% ethanol solubility, color, appearance, and identification by gas chromatography coupled to mass spectrometry detection...
January 2017: Pharmacognosy Magazine
https://www.readbyqxmd.com/read/28215499/near-binocular-visual-function-in-young-adult-orthokeratology-versus-soft-contact-lens-wearers
#15
Kate Gifford, Paul Gifford, Peter L Hendicott, Katrina L Schmid
PURPOSE: To compare near point binocular vision function of young adult myopes wearing orthokeratology (OK) lenses to matched single vision soft disposable contact lens (SCL) wearers. METHODS: A retrospective clinical record analysis of all OK wearers (18-30 years) presenting over an 18 month period was undertaken. Data was extracted for 17 OK wearers, with 17 SCL wearers matched for age, refractive error and duration of contact lens wear. Binocular vision data included horizontal phoria (phoria), horizontal base-in (BIFR) and base-out fusional reserves (BOFR) and accommodation accuracy (AA)...
February 15, 2017: Contact Lens & Anterior Eye: the Journal of the British Contact Lens Association
https://www.readbyqxmd.com/read/28215452/myopic-shift-5-years-after-intraocular-lens-implantation-in-the-infant-aphakia-treatment-study
#16
David R Weakley, Michael J Lynn, Lindreth Dubois, George Cotsonis, M Edward Wilson, Edward G Buckley, David A Plager, Scott R Lambert
PURPOSE: To report the myopic shift at 5 years of age after cataract surgery with intraocular lens (IOL) implantation for infants enrolled in the Infant Aphakia Treatment Study (IATS). METHODS: Refractions were performed at 1 month and every 3 months postoperatively until age 4 years and then at ages 4.25, 4.5, and 5 years. The change in refraction over time was estimated by linear mixed model analysis. RESULTS: Intraocular lens implantation was completed in 56 eyes; 43 were analyzed (median age, 2...
February 16, 2017: Ophthalmology
https://www.readbyqxmd.com/read/28213907/optimizing-the-analysis-of-dental-enamel-microstructure-in-intact-teeth
#17
Zulieth López Arrieta, Sergio Roberto Peres Line
In most mammalian species enamel prisms are regularly arranged in layers of alternating directions forming an angle of approximately 90°. These successive layers of prisms are known as Hunter-Schreger bands (HSBs). The analysis of HSBs may provide valuable information regarding the species life history, taxon and personal identification, with evident applicability in physical anthropology and forensics. Obtaining good quality digital images of HSBs in intact specimens is not always a feasible task. The major problems are the low contrast of images; the reflection of incident light, which may create areas of intense shine in digital images; and the abrupt decrease in the degree of illumination that occurs after light crosses the vertical cracks, frequently present in enamel...
February 17, 2017: Microscopy Research and Technique
https://www.readbyqxmd.com/read/28213256/carbon-polydimethylsiloxane-based-integratable-optical-technology-for-spectroscopic-analysis
#18
Hiroaki Nomada, Kinichi Morita, Hirokazu Higuchi, Hiroaki Yoshioka, Yuji Oki
A polydimethylsiloxane (PDMS)-based optical system has been demonstrated. To suppress intense background radiation due to multiple internal scatting in a transparent material, a composite structure of a carbon-PDMS compound and PDMS was proposed. The index matching of the real part of the refractive index can suppress internal scattering, and an absorption of 99-99.7% was attained by using carbon micro particles and carbon nano tubes. The black-PDMS light channel functions as a light filter for straight pass, and an optical density of 5 was obtained by bending the filter...
May 1, 2017: Talanta
https://www.readbyqxmd.com/read/28213016/walking-dead-permeabilization-of-heat-treated-geobacillus-stearothermophilus-atcc-12980-spores-under-growth-preventing-conditions
#19
Narjes Mtimet, Clément Trunet, Anne-Gabrielle Mathot, Laurent Venaille, Ivan Leguérinel, Louis Coroller, Olivier Couvert
Although heat treatment is probably the oldest and the most common method used to inactivate spores in food processes, the specific mechanism of heat killing of spores is still not fully understood. The purpose of this study is to investigate the evolution of the permeabilization and the viability of heat-treated spores during storage under growth-preventing conditions. Geobacillus stearothermophilus spores were heat-treated under various conditions of temperature and pH, and then stored under conditions of temperature and pH that prevent growth...
June 2017: Food Microbiology
https://www.readbyqxmd.com/read/28212858/refractive-index-and-thickness-determination-in-langmuir-monolayers-of-myelin-lipids
#20
Julio M Pusterla, Antonio A Malfatti-Gasperini, Ximena E Puentes-Martinez, Leide P Cavalcanti, Rafael G Oliveira
Langmuir monolayers at the air/water interface are widely used as biomembrane models and for amphiphilic molecules studies in general. Under controlled intermolecular organization (lateral molecular area), surface pressure, surface potential, reflectivity (R) and other magnitudes can be precisely determined on these planar monomolecular films. However, some physical parameters such as the refractive index of the monolayer (n) still remain elusive. The refractive index is very relevant because (in combination with R) it allows for the determination of the thickness of the film...
February 14, 2017: Biochimica et Biophysica Acta
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