scholarly journals The effect of photographic light brightness on cup to disc ratio grading

2021 ◽  
Vol 21 (1) ◽  
Author(s):  
Matthew J. McSoley ◽  
Eldar Rosenfeld ◽  
Alana Grajewski ◽  
Ta Chen Chang

Abstract Background Digital optic disc photographs are integral to remote telehealth ophthalmology, yet no quality control standards exist for the brightness setting of the images. This study evaluated the relationship between brightness setting and cup/disc ratio (c/d) grading among glaucoma specialists. Methods Optic disc photographs obtained during routine examinations under anesthesia were collected to construct an image library. For each optic disc, photographs were obtained at 3 light intensity settings: dark, medium, and bright. From the image library, photograph triads (dark, medium and bright) of 50 eyes (50 patients) were used to construct the study set. Nine glaucoma specialists evaluated the c/d of the study set photographs in randomized order. The relationships between the brightness levels and the c/d grading as well as graders’ years in practice and variability were evaluated. Results The c/d were graded as significantly larger in bright photographs when compared to photographs taken at the medium light intensity (0.53 vs 0.48, P < 0.001) as well as those taken at the dark setting (0.47, P < 0.001). In addition, no relationship was found between ophthalmologists’ years in practice and the variability of their c/d grading (P = 0.76). Conclusion Image brightness affects c/d grading of nonstereoscopic disc photographs. The brighter intensity is associated with larger c/d grading. Photograph brightness may be an important factor to consider when evaluating digital disc photographs.

2021 ◽  
Author(s):  
Matthew McSoley ◽  
Eldar Rosenfeld ◽  
Alana Grajewski ◽  
Ta Chen Chang

Abstract Background: Digital optic disc images are integral in remote telehealthcare, yet no quality control standards exist for the exposure setting of the images. This study evaluated the relationship between exposure setting and cup/disc ratio (c/d) grading among glaucoma specialists. Methods: Color disc photos were taken of 50 eyes of pediatric patients under anesthesia at 3 light exposure settings: dark, medium, and bright. 9 glaucoma specialists evaluated the c/d of the imaged discs in random order. The relationships between the exposure levels and the c/d estimates as well as between c/d size and variability were evaluated.Results: A total of 150 photos of 50 optic discs were graded. The c/d estimates were significantly larger among bright when compared to photos taken at the medium exposure setting(0.53 vs 0.48, P < 0.001) as well as the dark exposure setting (0.47, P < 0.001). In addition, images with larger mean c/d did not show more variability amongst readers (P = 0.59). Conclusion: Image exposure affects c/d grading of nonstereoscopic disc images. The brighter exposure is associated with larger c/d grading. Exposure consistency is key in longitudinal care.


2005 ◽  
Vol 169 (1) ◽  
pp. 73-82 ◽  
Author(s):  
Eric D. Spear ◽  
Davis T.W. Ng

The endoplasmic reticulum (ER) maintains an environment essential for secretory protein folding. Consequently, the premature transport of polypeptides would be harmful to the cell. To avert this scenario, mechanisms collectively termed “ER quality control” prevent the transport of nascent polypeptides until they properly fold. Irreversibly misfolded molecules are sorted for disposal by the ER-associated degradation (ERAD) pathway. To better understand the relationship between quality control and ERAD, we studied a new misfolded variant of carboxypeptidase Y (CPY). The molecule was recognized and retained by ER quality control but failed to enter the ERAD pathway. Systematic analysis revealed that a single, specific N-linked glycan of CPY was required for sorting into the pathway. The determinant is dependent on the putative lectin-like receptor Htm1/Mnl1p. The discovery of a similar signal in misfolded proteinase A supported the generality of the mechanism. These studies show that specific signals embedded in glycoproteins can direct their degradation if they fail to fold.


Ophthalmology ◽  
2010 ◽  
Vol 117 (11) ◽  
pp. 2061-2066 ◽  
Author(s):  
Felipe A. Medeiros ◽  
Luciana M. Alencar ◽  
Pamela A. Sample ◽  
Linda M. Zangwill ◽  
Remo Susanna Jr. ◽  
...  

2017 ◽  
pp. 21 ◽  
Author(s):  
Javier Carmona-Jiménez ◽  
Gustavo Montejano-Zurita

The results of a phycofloristic study on three springs in the Huasteca Potosina region are presented; 67 species are reported. Floristic similarities and differences among the springsare analized, as well as the relationship between species and environmental factors. Microhabitas were defined in the springs as well as the principal algal asociations that characterize them. Light intensity and current velocity are the most important factors affecting the predominant growth forms present in this type of habitat.


Weed Science ◽  
1993 ◽  
Vol 41 (4) ◽  
pp. 534-540 ◽  
Author(s):  
Ronald E. Jones ◽  
Robert H. Walker

Greenhouse and growth chamber experiments with potted plants were conducted to determine the effects of interspecific root and canopy interference, light intensity, and soil moisture on water uptake and biomass of soybean, common cocklebur, and sicklepod. Canopy interference and canopy plus root interference of soybean with common cocklebur increased soybean water uptake per plant and per unit leaf area. Root interference with soybean decreased common cocklebur water uptake per plant. Canopy interference of soybean with sicklepod increased soybean water uptake per unit leaf area, while root interference decreased uptake per plant. Combined root and canopy interference with soybean decreased water uptake per plant for sicklepod. Soybean leaf area and shoot weight were reduced by root interference with both weeds. Common cocklebur and sicklepod leaf area and shoot weight were reduced by root and canopy interference with soybeans. Only common cocklebur root weight decreased when canopies interfered and roots did not. The relationship between light intensity and water uptake per unit leaf area was linear in both years with water uptake proportional to light intensity. In 1991 water uptake response to tight was greater for common cocklebur than for sicklepod. The relationship between soil moisture level and water uptake was logarithmic. Common cocklebur water uptake was two times that of soybean or sicklepod at −2 kPa of pressure potential. In 1991 common cocklebur water uptake decreased at a greater rate than soybean or sicklepod in response to pressure potential changes from −2 to −100 kPa.


Machines ◽  
2020 ◽  
Vol 8 (4) ◽  
pp. 59
Author(s):  
Norbert Piotrowski

Single-sided lapping is one of the most effective planarization technologies. The process has relatively complex kinematics and it is determined by a number of inputs parameters. It has been noted that prediction of the tool wear during the process is critical for product quality control. To determine the profile wear of the lapping plate, a computer model which simulates abrasive grains trajectories was developed in MATLAB. Moreover, a data-driven technique was investigated to indicate the relationship between the tool wear uniformity and lapping parameters such as the position of conditioning rings and rotational speed of the lapping plate and conditioning rings.


2020 ◽  
Vol 112 (2) ◽  
pp. 1466-1470 ◽  
Author(s):  
James Eaves ◽  
Stephen Eaves ◽  
Chad Morphy ◽  
Chris Murray

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