نتایج جستجو برای: gas permeable lens

تعداد نتایج: 305961  

Journal: :Optics 2022

The purpose of this case report is to verify if the adaptation a rigid gas-permeable contact lens can improve VA and comfort in patient with complications derived from radial keratotomy (RK) surgery. A semi-scleral was fitted 46-year-old female who had undergone bilateral RK before 30 years. uncorrected distance visual acuity right eye (RE) left (LE) 0.5 0.6 logMAR (minimum angle resolution), r...

Journal: :Investigative ophthalmology & visual science 1985
B A Holden L Williams S G Zantos

To investigate the etiology of contact lens-induced transient endothelial changes (blebs) in the human cornea, the effects of five different stimuli on corneal thickness and the appearance of the corneal endothelium were assessed. The stimuli included: (1) a silicone contact lens; (2) a silicone contact lens in combination with anoxia; (3) anoxia alone; (4) a thick hydroxyethyl methacrylate (HE...

Journal: :Journal of cell science 2000
V I Shestopalov S Bassnett

The lens of the eye is composed of concentric layers of tightly packed fiber cells. The oldest fibers, those in the lens core, lose their nuclei and other organelles during terminal differentiation. This is thought to ensure the clarity of the lens. The anucleated core fibers are sustained by gap junction-mediated communication with metabolically active cells near the lens surface. In this stud...

Journal: :Journal of Photopolymer Science and Technology 2017

Journal: :Angewandte Chemie 2014
Cher Hon Lau Phuc Tien Nguyen Matthew R Hill Aaron W Thornton Kristina Konstas Cara M Doherty Roger J Mulder Laure Bourgeois Amelia C Y Liu David J Sprouster James P Sullivan Timothy J Bastow Anita J Hill Douglas L Gin Richard D Noble

Aging in super glassy polymers such as poly(trimethylsilylpropyne) (PTMSP), poly(4-methyl-2-pentyne) (PMP), and polymers with intrinsic microporosity (PIM-1) reduces gas permeabilities and limits their application as gas-separation membranes. While super glassy polymers are initially very porous, and ultra-permeable, they quickly pack into a denser phase becoming less porous and permeable. This...

Journal: :Journal of neuroscience methods 2001
A B Metha A M Crane H G Rylander S L Thomsen D G Albrecht

Neurophysiologists have been investigating the responses of neurons in the visual system for the past half-century using monkeys and cats that are anesthetized and paralyzed, with the non-blinking eyelids open for prolonged periods of time. Impermeable plastic contact lenses have been used to prevent dehydration of the corneal epithelium, which would otherwise occur in minutes. Unfortunately, s...

Journal: :Investigative ophthalmology & visual science 2011
Oscar A Candia

I was excited by the results presented in the excellent paper by Sheppard et al. showing a 2.3% increase in lens volume and a decrease of 1.82% in surface during accommodation in human volunteers. I was very gratified that they acknowledged that we had predicted similar changes in human lens volume and surface based on mathematical modeling of human lens dimensions, using the Pappus theorem as ...

2015
Nathalie E Zeitouni Joachim Fandrey Hassan Y Naim Maren von Köckritz-Blickwede

PURPOSE Measuring oxygen levels in three different systems of Caco-2 cell culture. METHODS Caco-2 cells were cultured in three different systems, using conventional polystyrene 24-well plates, special 24-well gas permeable plates, or on membrane inserts in conventional plates. Optical sensor spots were used to measure dissolved O2 levels in these cultured cells over the course of 6 days under...

2008
Junichiro Kugai

Heat and mass transfer problem in a fixed-bed tubular reactor is one of the major concerns in the chemical engineering. The two dimensional axial plug flow model was used for a water gas shift reactor to compare heat conduction or mass diffusion with convective effect. In the case of fast fluid flow in highly permeable catalyst-bed, convective heat transfer was dominant compared to heat conduct...

نمودار تعداد نتایج جستجو در هر سال

با کلیک روی نمودار نتایج را به سال انتشار فیلتر کنید