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https://www.readbyqxmd.com/read/28434385/digital-curation-and-online-resources-digital-scanning-of-surgical-tools-at-the-royal-college-of-physicians-and-surgeons-of-glasgow-for-an-open-university-learning-resource
#1
Kirsty Earley, Daniel Livingstone, Paul M Rea
Collection preservation is essential for the cultural status of any city. However, presenting a collection publicly risks damage. Recently this drawback has been overcome by digital curation. Described here is a method of digitisation using photogrammetry and virtual reality software. Items were selected from the Royal College of Physicians and Surgeons of Glasgow archives, and implemented into an online learning module for the Open University. Images were processed via Agisoft Photoscan, Autodesk Memento, and Garden Gnome Object 2VR...
January 2017: Journal of Visual Communication in Medicine
https://www.readbyqxmd.com/read/28427301/corneal-endothelial-changes-in-long-term-cannabinoid-users
#2
Nihat Polat, Birgul Cumurcu, Tongabay Cumurcu, İlknur Tuncer
PURPOSE: The aim of this study was to evaluate the effects of long-term cannabis use on the corneal endothelial cells with the specular microscopy. METHODS: The study enrolled 28 eyes of 28 patients diagnosed with cannabinoid use disorder. The cannabinoid group was selected among patients who had been using the substance for 3 days or more per week over the past 1 year. 32 eyes of 32 age- and sex-matched healthy individuals enrolled as control group in the study...
April 20, 2017: Cutaneous and Ocular Toxicology
https://www.readbyqxmd.com/read/28422428/identification-of-novel-transthyretin-fibril-formation-inhibitors-using-structure-based-virtual-screening
#3
Gabriella Ortore, Adriano Martinelli
Transthyretin (TTR) is the primary carrier for thyroxine (T4) in cerebrospinal fluid and a secondary carrier in blood. TTR is a stable homotetramer, but certain factors, genetic or environmental, could promote its degradation to form amyloid fibrils. A docking study in the wild-type TTR crystal structures was planned; our aim was to design new ligands able to inhibit TTR fibril formation. The computational protocol was thought to overcome the multiple binding modes of the ligands induced by the specularity of the TTR binding site and by the pseudosymmetry of the site pockets, which generally weaken such structure-based studies...
April 19, 2017: ChemMedChem
https://www.readbyqxmd.com/read/28415262/thermophoretic-force-on-nanocylinders-in-the-free-molecule-regime
#4
Jun Wang, Shuang Luo, Guodong Xia
We theoretically investigate the thermophoresis of nanocylinders in the free molecule regime, wherein the nonrigid-body effect is taken into account. The analytical formulas of the thermophoretic forces on cylinders suspended in both simple gases and binary gas mixtures are derived for the two limiting collision models, i.e., specular and diffuse scatterings, based on the gas kinetic theory. In the limit of the rigid-body collision, the expressions can be reduced to the theoretical results of Garcia-Ybarra and Rosner [AIChE J...
March 2017: Physical Review. E
https://www.readbyqxmd.com/read/28414357/infrared-brewster-angle-polarizing-beam-splitter-using-a-high-index-prism-with-a-small-wedge-angle
#5
R M A Azzam
Specular reflection at the Brewster angle by a planar surface of a high-refractive-index transparent substrate is an effective means of generating linearly polarized light in the infrared. However, in such a reflection linear polarizer, the refracted light beam is usually dumped. In this paper we describe a polarizing beam splitter (PBS) that uses a high-index prism with a small wedge angle to generate two orthogonally p and s linearly polarized beams that travel in orthogonal directions. A single-layer antireflection coating (ARC) at the exit face of the prism can be embedded with aligned Ag nano needles to suppress the transmission of the small, residual, s-polarized refracted component...
April 10, 2017: Applied Optics
https://www.readbyqxmd.com/read/28398905/an-integrated-model-of-scintillator-reflector-properties-for-advanced-simulations-of-optical-transport
#6
Emilie Roncali, Mariele Stockhoff, Simon Cherry
Accurately modeling the light transport in scintillation detectors is essential to design new detectors for nuclear medicine or high energy physics. Optical models implemented in software such as Geant4 and GATE suffer from important limitations that we addressed by implementing a new approach in which the crystal reflectance was computed from 3D surface measurements. The reflectance was saved in a look-up-table (LUT) then used in Monte Carlo simulation to determine the fate of optical photons. Our previous work using this approach demonstrated excellent agreement with experimental characterization of crystal light output in a limited configuration, i...
April 11, 2017: Physics in Medicine and Biology
https://www.readbyqxmd.com/read/28388176/role-of-magnetosonic-solitons-in-perpendicular-collisionless-shock-reformation
#7
Renaud Gueroult, Yukiharu Ohsawa, Nathaniel J Fisch
The nature of the magnetic structure arising from ion specular reflection in shock compression studies is examined by means of 1D particle-in-cell simulations. Propagation speed, field profiles, and supporting currents for this magnetic structure are shown to be consistent with a magnetosonic soliton. Coincidentally, this structure and its evolution are typical of foot structures observed in perpendicular shock reformation. To reconcile these two observations, we propose, for the first time, that shock reformation can be explained as the result of the formation, growth, and subsequent transition to a supercritical shock of a magnetosonic soliton...
March 24, 2017: Physical Review Letters
https://www.readbyqxmd.com/read/28383814/specular-and-diffuse-reflectance-of-phase-separated-polymer-blend-films
#8
Asritha Nallapaneni, Matthew D Shawkey, Alamgir Karim
Diffuse reflectors have various applications in devices ranging from liquid crystal displays to light emitting diodes, to coatings. Herein, specular and diffuse reflectance from controlled phase separation of polymer blend films, a well-known self-organization process, are studied. Temperature-induced spinodal phase separation of polymer blend films in which one of the components is selectively extracted is shown to exhibit enhanced surface roughness as compared to unextracted films, leading to a notable increase of diffuse reflectance...
April 6, 2017: Macromolecular Rapid Communications
https://www.readbyqxmd.com/read/28380864/transient-polarized-radiative-transfer-analysis-in-a-scattering-medium-by-a-discontinuous-finite-element-method
#9
Cun-Hai Wang, Hong-Liang Yi, He-Ping Tan
Transient (time-dependent) polarized radiative transfer in a scattering medium exposed to an external collimated beam illumination is conducted based on the time-dependent polarized radiative transfer theory. The transient term, which persists the nanosecond order time and cannot be ignored for the time-dependent radiative transfer problems induced by a short-pulsed beam, is considered as well as the polarization effect of the radiation. A discontinuous finite element method (DFEM) is developed for the transient vector radiative transfer problem and the derivation of the discrete form of the governing equation is presented...
April 3, 2017: Optics Express
https://www.readbyqxmd.com/read/28380096/visual-rehabilitation-using-mini-scleral-contact-lenses-after-penetrating-keratoplasty
#10
Guilherme Andrade do Nascimento Rocha, Patrícia Oliveira Braga Miziara, Ana Clara Vieira de Castro, Arthur Andrade do Nascimento Rocha
Purpose: To report the visual rehabilitation outcomes and complications of patients fitted with mini-scleral rigid gas-permeable (RGP) contact lenses (mini-SCLs) after penetrating keratoplasty. Methods: We retrospectively reviewed 27 eyes (21 patients) that were fitted with mini-SCLs between October 2013 and December 2014. We analyzed demographic data, previous corneal disorders, visual outcomes, interval from keratoplasty to contact lens fitting, topographic and specular microscope data, fitted contact lens parameters, and complications...
January 2017: Arquivos Brasileiros de Oftalmologia
https://www.readbyqxmd.com/read/28374155/morphometry-of-organ-cultured-corneal-endothelium-using-voronoi-segmentation
#11
Nigel H Brookes
The endothelial viability of eye-banked corneas must be assessed before transplantation, yet phase-contrast images of the endothelium of corneas stored in an Organ Culture system have a huge variety of endothelial appearance at different focal planes, due to stromal swelling and an evaluation technique that swells the cells and their intercellular spaces to make them visible. This makes them difficult to assess using common edge-based segmentation methodologies that have mostly been developed in vivo using specular microscopy...
April 3, 2017: Cell and Tissue Banking
https://www.readbyqxmd.com/read/28368996/evaluation-of-angle-closure-as-a-risk-factor-for-reduced-corneal-endothelial-cell-density
#12
Varshini Varadaraj, Sabyasachi Sengupta, Krishnamurthy Palaniswamy, Kavitha Srinivasan, Mohideen A Kader, Ganesh Raman, Sharmila Reddy, Pradeep Y Ramulu, Rengaraj Venkatesh
PURPOSE: Acute angle closure attacks are frequently accompanied by corneal edema. However, little is known about corneal endothelial cell status at different stages of angle closure. Here, we compared endothelial cell density (ECD) in unoperated eyes with that in eyes with open angles (OAs) and various stages of angle closure disease. MATERIALS AND METHODS: The study was conducted at Aravind Eye Hospitals in India. Masked examiners performed gonioscopy to classify each eye as follows: (1) OA, (2) primary angle closure suspect, or (3) primary angle closure (PAC)/primary angle closure glaucoma (PACG)...
March 31, 2017: Journal of Glaucoma
https://www.readbyqxmd.com/read/28362789/digital-micromirror-device-based-common-path-quantitative-phase-imaging
#13
Cheng Zheng, Renjie Zhou, Cuifang Kuang, Guangyuan Zhao, Zahid Yaqoob, Peter T C So
We propose a novel common-path quantitative phase imaging (QPI) method based on a digital micromirror device (DMD). The DMD is placed in a plane conjugate to the objective back-aperture plane for the purpose of generating two plane waves that illuminate the sample. A pinhole is used in the detection arm to filter one of the beams after sample to create a reference beam. Additionally, a transmission-type liquid crystal device, placed at the objective back-aperture plane, eliminates the specular reflection noise arising from all the "off" state DMD micromirrors, which is common in all DMD-based illuminations...
April 1, 2017: Optics Letters
https://www.readbyqxmd.com/read/28362786/dark-field-brillouin-microscopy
#14
Giuseppe Antonacci
Brillouin microscopy is a non-contact and label-free technique for mapping fundamental micro-mechanical properties in the volume of biological systems. Specular reflections and elastic scattering easily overwhelm the weak Brillouin spectra due to the limited extinction of virtually imaged phased array spectrometers, thereby affecting the image acquisition. In this Letter, a dark-field method was demonstrated to reject the elastic background light using an annular illumination and a confocal detection. To validate the method, images of polystyrene and liquid samples were obtained using both a confocal and the dark-field system...
April 1, 2017: Optics Letters
https://www.readbyqxmd.com/read/28355488/spectrophotometry-of-thin-films-of-light-absorbing-particles
#15
Bernard P Binks, Paul D I Fletcher, Andrew J Johnson, Ioannis Marinopoulos, Jonathan M Crowther, Michael A Thompson
Thin films of dispersions of light-absorbing solid particles or emulsions containing a light-absorbing solute all have a nonuniform distribution of light-absorbing species throughout the sample volume. This results in nonuniform light absorption over the illuminated area, which causes the optical absorbance, as measured using a conventional specular UV-vis spectrophotometer, to deviate from the Beer-Lambert relationship. We have developed a theoretical model to account for the absorbance properties of such films, which are shown to depend on the size and volume fraction of the light-absorbing particles plus other sample variables...
April 6, 2017: Langmuir: the ACS Journal of Surfaces and Colloids
https://www.readbyqxmd.com/read/28347727/a-novel-method-for-examining-corneal-endothelial-cell-morphology-in-infants
#16
S R Rufai, N Y Tan, R Barbara, R Hartrey, J E Self
Previous studies suggest that central corneal endothelial cell density (ECD) decreases from 6,100 cells/mm(2) in neonates to 3,100 cells/mm(2) in 10-year-olds. Currently, there is very sparse data regarding ECD in young children as well as the trend in which ECD decreases during childhood. This is because young children were unable to comply with existing clinic-based specular microscopes. Hence, we developed a novel method of imaging young children intra-operatively to help establish age-specific normative data for ECD and hexagonality of cells (%HEX)...
March 24, 2017: Journal of AAPOS: the Official Publication of the American Association for Pediatric Ophthalmology and Strabismus
https://www.readbyqxmd.com/read/28346276/comparison-of-noncontact-specular-and-confocal-microscopy-for-evaluation-of-corneal-endothelium
#17
Jianyan Huang, Jyotsna Maram, Tudor C Tepelus, Srinivas R Sadda, Vikas Chopra, Olivia L Lee
PURPOSE: To compare endothelial cell analysis obtained by noncontact specular and confocal microscopy, using the Konan NSP-9900 and Nidek ConfoScan4 systems, respectively. METHODS: Three groups including 70 healthy eyes, 49 eyes with Fuchs endothelial corneal dystrophy (FECD), and 78 eyes with glaucoma were examined with both the Konan NSP-9900 specular microscope and the Nidek ConfocScan4 confocal microscope. Certified graders at the Doheny Image Reading Center compared corneal endothelial images from both instruments side by side to assess image quality...
March 24, 2017: Eye & Contact Lens
https://www.readbyqxmd.com/read/28335330/carbon-nanotube-cnt-honeycomb-cell-area-dependent-optical-reflectance
#18
Junthorn Udorn, Akimitsu Hatta, Hiroshi Furuta
The relationship between the physical structure of carbon nanotube (CNT) honeycomb structures and their total, diffuse, and specular reflectance is investigated for the first time. It is found that CNT honeycomb structures with average cell areas of smaller than 30 μm² show a higher total reflectance. Particularly, a thinner, highly packed CNT (buckypaper) film, along with a larger wall height and higher ratio of wall height to cell area, markedly increase the total reflectance for cell areas smaller than 30 μm², which means that a higher total area of buckypapers in CNT walls and bottom areas increases the total reflectance, including the diffuse reflectance...
November 7, 2016: Nanomaterials
https://www.readbyqxmd.com/read/28325898/experimental-evidence-suggests-that-specular-reflectance-and-glossy-appearance-help-amplify-warning-signals
#19
Samuel J Waldron, John A Endler, Janne K Valkonen, Atsushi Honma, Susanne Dobler, Johanna Mappes
Specular reflection appears as a bright spot or highlight on any smooth glossy convex surface and is caused by a near mirror-like reflectance off the surface. Convex shapes always provide the ideal geometry for highlights, areas of very strong reflectance, regardless of the orientation of the surface or position of the receiver. Despite highlights and glossy appearance being common in chemically defended insects, their potential signalling function is unknown. We tested the role of highlights in warning colouration of a chemically defended, alpine leaf beetle, Oreina cacaliae...
March 21, 2017: Scientific Reports
https://www.readbyqxmd.com/read/28306601/assessing-the-impact-of-diabetes-mellitus-on-donor-corneal-endothelial-cell-density
#20
Chase A Liaboe, Benjamin T Aldrich, Pamela C Carter, Jessica M Skeie, Kimberlee A Burckart, Gregory A Schmidt, Cynthia R Reed, M Bridget Zimmerman, Mark A Greiner
PURPOSE: To quantify changes in endothelial cell density (ECD) of donor corneal tissue in relation to the presence or absence of a medical history of diabetes mellitus diagnosis, treatment, and complications. METHODS: A retrospective review was performed for all corneas collected at Iowa Lions Eye Bank between January 2012 and December 2015. For purposes of analysis, donor corneas were divided into 4 groups: nondiabetic, non-insulin-dependent diabetic, insulin-dependent diabetic without medical complications due to diabetes, and insulin-dependent diabetic with medical complications due to diabetes...
May 2017: Cornea
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