scholarly journals Evaluation of tablet-based methods for assessment of contrast sensitivity

2020 ◽  
Vol 2020 (11) ◽  
pp. 210-1-210-7
Author(s):  
Jeffrey B. Mulligan
Keyword(s):  
Contrast Sensitivity ◽  
Morphological Changes ◽  
Rapid Assessment ◽  
Visual Threshold ◽  
Vision Assessment ◽  
Long Duration ◽  
Peak Sensitivity ◽  
Novel Method ◽  
The Subject ◽  
Functional Vision Assessment

Some astronauts have suffered degradation of vision during long-duration space flight, suffering from a condition that has come to be known as Spaceflight Associated Neuro-ocular Syndrome (SANS). While related morphological changes can be observed with imaging technologies such as optical coherence tomography (OCT), it may be useful to have a rapid method for functional vision assessment. In this paper, we compare three tablet-based methods for rapid assessment of contrast sensitivity. First, a relatively novel method developed expressly for touch screens, in which the subject “swipes” a frequency/contrast sweep grating to indicate the boundary between visible and invisible patterns; second, a method-of-adjustment task in which the subject adjusts the contrast of a grating patch up and down to bracket the visual threshold; and third, a traditional temporal two-alternative forced choice (2AFC) task, in which the subject is presented with a near-threshold stimulus in one of two intervals, and must report the interval containing the stimulus. The swipe method shows variability comparable to the 2AFC method, and shows good agreement in estimates of the spatial frequency of peak sensitivity. The absolute sensitivity estimated with the swipe method is higher than that of the other methods, perhaps because subjects are biased to trace outside of the visible pattern region, or perhaps due to stimulus differences.

The removal and morphology of intact biofilms from implanted venous access devices

1995 ◽  
Vol 53 ◽  
pp. 1020-1021
Author(s):  
M.A. Gregory ◽  
G.P. Hadley
Keyword(s):  
Patient Selection ◽  
Surgical Oncology ◽  
Venous Access ◽  
Common Procedure ◽  
Indwelling Catheters ◽  
Careful Patient ◽  
Novel Method ◽  
The Subject ◽  
Vascular Catheters ◽  
Venous Access Devices

The insertion of implanted venous access systems for children undergoing prolonged courses of chemotherapy has become a common procedure in pediatric surgical oncology. While not permanently implanted, the devices are expected to remain functional until cure of the primary disease is assured. Despite careful patient selection and standardised insertion and access techniques, some devices fail. The most commonly encountered problems are colonisation of the device with bacteria and catheter occlusion. Both of these difficulties relate to the development of a biofilm within the port and catheter. The morphology and evolution of biofilms in indwelling vascular catheters is the subject of ongoing investigation. To date, however, such investigations have been confined to the examination of fragments of biofilm scraped or sonicated from sections of catheter. This report describes a novel method for the extraction of intact biofilms from indwelling catheters.15 children with Wilm’s tumour and who had received venous implants were studied. Catheters were removed because of infection (n=6) or electively at the end of chemotherapy.

FUNCTIONAL METHODS OF EARLY DIAGNOSTICS OF AGE MACULAR DEGENERATION.(LITERATURE REVIEW)

2021 ◽  
Vol Special issue (2) ◽  
pp. 61-67
Author(s):  
Azamat Yusupov ◽  
◽  
Mukhiddin Ziyoviddinov ◽  
Shavkat Mukhanov ◽  
O.O. Sobirov
Keyword(s):  
Literature Review ◽  
Macular Degeneration ◽  
Contrast Sensitivity ◽  
Morphological Changes ◽  
Pigment Epithelium ◽  
Sensitivity Study ◽  
Age Related Macular Degeneration ◽  
Functional Diagnostics ◽  
Advantages And Disadvantages ◽  
Age Related

This article provides an unsystematic literature review devoted to analyzing the currently existing methods of functional diagnostics for age-related macular degeneration.The essence, advantages and disadvantages, and literature data on the use of such methods asphotostresstest, electrooculography, dark adaptation study, contrast sensitivity function assessment, light and color sensitivity study,electroretinographyand critical flicker fusion frequencyare described.Based on the analysis of literature data, itis shownthat currently, there is a need to searchfor informative and accessible methods of functional diagnostics in age-related macular degeneration, especially for its early diagnosis. The analysis has shown that the existing methods are mainly aimed either at fixing secondary morphological changes in the layer of pigment epithelial cells, at identifying the pathology of the pigment epithelium in conjunction with determining the function of photoreceptor elements, or at a comprehensive assessment of the structures of several layers of the retina. Keywords:age-related macular degeneration; methods of functional diagnostics; photostress test; electrooculography; contrast sensitivity

scholarly journals Long-Exposure RGB Photography with a Fixed Stand for the Measurement of a Trajectory of a Dynamic Impact Device in Real Scale

Sensors ◽  
2021 ◽  
Vol 21 (20) ◽  
pp. 6818
Author(s):  
Ľudovít Kovanič ◽  
Ľubomír Ambriško ◽  
Daniela Marasová ◽  
Peter Blišťan ◽  
Tomáš Kasanický ◽  
...  
Keyword(s):  
Impact Resistance ◽  
Dynamic Impact ◽  
Long Duration ◽  
Conveyor Belts ◽  
Laser Distance Sensor ◽  
Novel Method ◽  
Distance Sensor ◽  
Reference Measurements ◽  
Real Scale

The present manuscript proposes a novel method for the measurement of a trajectory of a falling impact hammer in the dynamic loading of conveyor belts and the determination of their impact resistance. The proposed method has been experimentally tested and the results of the measurements are presented in this manuscript. The proposed method is based on the long-exposure photography with a long-duration opened shutter of the Nikon D5000 DSLR camera. Results of the experimental research were compared with direct reference measurements performed using the L-GAGE LT3 laser distance sensor. Differences between values, obtained by the new method and by the reference measurements were up to ±3 mm. The standard deviation identified in all the experiments was 1 mm.

Community management of burn injuries

2019 ◽  
Vol 12 (8) ◽  
pp. 459-465
Author(s):  
Nader Henry ◽  
Ishan Radotra ◽  
Sheirin Khalil
Keyword(s):  
Primary Care ◽  
Rapid Assessment ◽  
Burn Injuries ◽  
Community Management ◽  
Referral Criteria ◽  
Rapid Assessment Methods ◽  
Adults And Children ◽  
The Subject ◽  
Key Aspects

Burn injuries are extremely common injuries for both adults and children, and yet knowledge of their management is often lacking in society and the subject is not routinely taught to clinicians. In this article, we aim to provide an overview of the pertinent points of the history, classification of burns, and rapid assessment methods for determining body surface area within primary care. This is followed by key aspects of management, referral criteria for transfer to a burns service, and important safeguarding issues surrounding burns.

scholarly journals FLORA™: Phase I development of a functional vision assessment for prosthetic vision users

2015 ◽  
Vol 98 (4) ◽  
pp. 342-347 ◽  
Author(s):  
Duane R Geruschat ◽  
Marshall Flax ◽  
Nilima Tanna ◽  
Michelle Bianchi ◽  
Andy Fisher ◽  
...  
Keyword(s):  
Phase I ◽  
Vision Assessment ◽  
Functional Vision ◽  
Functional Vision Assessment

scholarly journals Production of Gamma Alumina Using Plasma-Treated Aluminum and Water Reaction Byproducts

Materials ◽  
2020 ◽  
Vol 13 (6) ◽  
pp. 1300 ◽  
Author(s):  
Marius Urbonavicius ◽  
Sarunas Varnagiris ◽  
Liudas Pranevicius ◽  
Darius Milcius
Keyword(s):  
High Purity ◽  
High Efficiency ◽  
Morphological Changes ◽  
Cost Effective ◽  
Electrical Energy ◽  
High Specific Surface Area ◽  
Direct Reaction ◽  
Gamma Alumina ◽  
Novel Method ◽  
High Purity Hydrogen

High purity hydrogen and solid-state byproducts are produced using a proposed plasma-activated aluminum and water reactions approach. These byproducts could be transformed into pure gamma Al2O3 powder material, while hydrogen can be used for electricity generation. Various chemical methods can be used for the synthesis of gamma alumina, but most could result in high levels of remaining impurities. Boehmite is a cost-effective starting material for the production of high-purity Al2O3. Herein, we present a novel method for the synthesis of boehmite and its transformation into high-specific-surface-area γ-alumina. Specifically, this method implicates the direct reaction between distilled water and plasma-treated aluminum powder. The results show the structural and morphological changes of the byproduct of the aluminum/water reaction to boehmite and γ-Al2O3 after a simple heating procedure (at 280 and 500 °C respectively). The high-purity hydrogen produced during the aluminum/water reaction can be used for the high-efficiency and environmentally friendly production of electrical energy.

scholarly journals Measuring Differential Volume Using the Subtraction Tool for Three-Dimensional Breast Volumetry: A Proof of Concept Study

2020 ◽  
pp. 155335062094556
Author(s):  
Faith Hyun Kyung Jeon ◽  
Michelle Griffin ◽  
Aurora Almadori ◽  
Jajini Varghese ◽  
Stephanie Bogan ◽  
...  
Keyword(s):  
Three Dimensional ◽  
Computer Software ◽  
Patient Positioning ◽  
Volumetric Analysis ◽  
Volumetric Assessment ◽  
Alternative Approach ◽  
Significant Difference ◽  
Actual Volume ◽  
Novel Method ◽  
The Subject

Background. Three-dimensional (3D) photography provides a promising means of breast volumetry. Sources of error using a single-captured surface to calculate breast volume include inaccurate designation of breast boundaries and prediction of the invisible chest wall generated by computer software. An alternative approach is to measure differential volume using subtraction of 2 captured surfaces. Objectives. To explore 3D breast volumetry using the subtraction of superimposed images to calculate differential volume. To assess optimal patient positioning for accurate volumetric assessment. Methods. Known volumes of breast enhancers simulated volumetric changes to the breast (n = 12). 3D photographs were taken (3dMDtorso) with the subject positioned upright at 90° and posteriorly inclined at 30°. Patient position, breathing, distance and camera calibration were standardised. Volumetric analysis was performed using 3dMDvultus software. Results. A statistically significant difference was found between actual volume and measured volumes with subjects positioned at 90° ( P < .05). No statistical difference was found at 30° ( P = .078), but subsequent Bland–Altman analysis showed evidence of proportional bias ( P < .05). There was good correlation between measured and actual volumes in both positions (r = .77 and r = .85, respectively). Univariate analyses showed breast enhancer volumes of 195 mL and 295 mL to incur bias. The coefficient of variation was 5.76% for single observer analysis. Conclusion. Positioning the subject at a 30° posterior incline provides more accurate results from better exposure of the inferior breast. The subtraction tool is a novel method of measuring differential volume. Future studies should explore methodology for application into the clinical setting.

scholarly journals Active nitrogen of long duration, law of decay, and of increased brightness on compression

1935 ◽  
Vol 151 (874) ◽  
pp. 567-584 ◽  
Keyword(s):  
Small Area ◽  
Copper Surface ◽  
Metal Electrodes ◽  
Experimental Conditions ◽  
Active Nitrogen ◽  
Mercury Surface ◽  
Long Duration ◽  
Unfavourable Effect ◽  
The Subject ◽  
Low Pressures

1-Active Nitrogen-Influence of Vessel Walls on the Duration The length of time for which the afterglow associated with active nitrogen remains perceptible varies very greatly under different experimental conditions; and, what is more important, if we start from a given luminosity per cc of the gas, the integrated amount of light emitted before the luminosity sinks to zero varies also. This is connected with the fact that the walls of the certain gaseous impurities may have an unfavourable effect. In other words, the active nitrogen may go out of existence either by a luminous or a non-luminous reaction. If it is desired to study the homogeneous luminous reaction, then it becomes important to eliminate the other as far as possible. So far as I am aware, no systematic attempt has ever been made to do this, though many writers have referred to the subject. The electrodelss ring discharge at low pressures is suited for the production of active nitrogen, and it has the advantage that no metal electrodes need be introduced. An oxidized copper surface, even of very small area, immediately destroys the afterglow when introduced into it, and a clean (freshly formed) mercury surface is attacked with formation of nitride. In view of these facts it seemed best to avoid metal, though more information would be desirable.

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