scholarly journals A COMPREHENSIVE APPROACH INTO STEREOSCOPIC VISION

2022 ◽  
Vol 8 (1) ◽  
pp. 53-57
Author(s):  
Lely Retno Wulandari
Keyword(s):  
Three Dimensional ◽  
Stereoscopic Vision ◽  
Daily Activities ◽  
Qualitative And Quantitative ◽  
Daily Life Activities ◽  
Examination Methods ◽  
Quantitative Examination ◽  
The Difference ◽  
Angle Of View ◽  
The Brain

Stereopsis (or stereoscopic) vision is the ability to see depth of perception, which is created by the difference in angle of view between both eyes. The first process is known as simultaneous perception. Objects will fall on each corresponding retina and there will be a process of fusion of the two images into one. Then, the brain initiates three-dimensional perception in visual cortex, creating stereoscopic vision. Stereoscopic vision will rapidly develop, especially at the age of 6-8 months of life. Stereoscopic is important in daily activities. There are many stereoacuity tests to evaluate stereoscopic vision. Stereoscopic examinations are based on the principle of haploscope, anaglyph, or polaroid vectograph. There are qualitative and quantitative examination methods to assess stereoscopic vision. Qualitative examinations such as Horizontal Lang Two Pencil test and Synoptophore. Quantitative examination including Contour stereopsis test and Clinical random dot stereopsis test. The inability of the eye to see stereoscopic can be called stereoblindness. This can be affected by amblyopia, decreased visual acuity, or the presence of ocular misalignment. Inability to achieve stereoscopic vision will impact an individual to perform some daily life activities, and lead to an increase in difficulty interacting in the world.

scholarly journals Effects of cortical damage on binocular depth perception

2016 ◽  
Vol 371 (1697) ◽  
pp. 20150254 ◽  
Author(s):  
Holly Bridge
Keyword(s):  
Depth Perception ◽  
Three Dimensional ◽  
Stereoscopic Vision ◽  
Temporal Lobectomy ◽  
Cortical Atrophy ◽  
Retinal Images ◽  
Posterior Cortical Atrophy ◽  
Retinal Input ◽  
The Brain ◽  
Binocular Depth

Stereoscopic depth perception requires considerable neural computation, including the initial correspondence of the two retinal images, comparison across the local regions of the visual field and integration with other cues to depth. The most common cause for loss of stereoscopic vision is amblyopia, in which one eye has failed to form an adequate input to the visual cortex, usually due to strabismus (deviating eye) or anisometropia. However, the significant cortical processing required to produce the percept of depth means that, even when the retinal input is intact from both eyes, brain damage or dysfunction can interfere with stereoscopic vision. In this review, I examine the evidence for impairment of binocular vision and depth perception that can result from insults to the brain, including both discrete damage, temporal lobectomy and more systemic diseases such as posterior cortical atrophy. This article is part of the themed issue ‘Vision in our three-dimensional world’.

scholarly journals Quantitative analysis of hydrocephalic ventricular alterations in Yorkshire terriers using magnetic resonance imaging

2010 ◽  
Vol 55 (No. 3) ◽  
pp. 125-132 ◽  
Author(s):  
D-C Woo ◽  
C-B Choi ◽  
J-W Nam ◽  
K-N Ryu ◽  
G-H Jahng ◽  
...  
Keyword(s):  
Quantitative Analysis ◽  
Quantitative Methods ◽  
Statistical Significance ◽  
Three Dimensional ◽  
Low Field ◽  
Brain Ventricle ◽  
The Difference ◽  
Ventricle Size ◽  
The Brain ◽  
Area And Volume

The purpose of this work was to evaluate hydrocephalic ventricular changes using three quantitative analysis methods. The height, area and volume of the ventricles and brain were measured in 20 Yorkshire terriers (10 normal and 10 hydrocephalic dogs) using low-field MR imaging (at 0.2 Tesla). All measurements were averaged and the relative ventricle size was defined as a percentage (percent size of the ventricle/size of the brain). The difference between normal and hydrocephalic dogs was statistically significant for the average of each ventricle as well as for the percentage value. Five hydrocephalic symptoms were identified: circling, head tilting, seizures, ataxia, and strabismus. With respect to height, area and volume of the brain/ventricle, the difference between normal and hydrocephalic dogs was not significant. The ventricle/brain with height (1D) was related to the area (2D) and volume (3D). The correlations with area and volume were as good as the ventricle/brain height ratio in the case of hydrocephalic dogs. Therefore, one-, two- and three-dimensional quantitative methods may be complementary. We expect that the stage of hydrocephalic symptoms can be classified if statistical significance for ventricular size among symptoms is determined with the analysis of a large number of hydrocephalic cases.

Defocus ramp correction in spot-scan imaging

1992 ◽  
Vol 50 (1) ◽  
pp. 130-131
Author(s):  
Kenneth H. Downing
Keyword(s):  
Computer Control ◽  
Three Dimensional ◽  
Sufficient Accuracy ◽  
Objective Lens ◽  
Electron Crystallography ◽  
Contrast Transfer Function ◽  
Tilt Axis ◽  
Specimen Height ◽  
The Difference ◽  
Envelope Functions

Three-dimensional structures of a number of samples have been determined by electron crystallography. The procedures used in this work include recording images of fairly large areas of a specimen at high tilt angles. There is then a large defocus ramp across the image, and parts of the image are far out of focus. In the regions where the defocus is large, the contrast transfer function (CTF) varies rapidly across the image, especially at high resolution. Not only is the CTF then difficult to determine with sufficient accuracy to correct properly, but the image contrast is reduced by envelope functions which tend toward a low value at high defocus.We have combined computer control of the electron microscope with spot-scan imaging in order to eliminate most of the defocus ramp and its effects in the images of tilted specimens. In recording the spot-scan image, the beam is scanned along rows that are parallel to the tilt axis, so that along each row of spots the focus is constant. Between scan rows, the objective lens current is changed to correct for the difference in specimen height from one scan to the next.

High Performance Thin Layer Chromatography (HPTLC) for the Investigation of Medicinal Plants

2020 ◽  
Vol 16 ◽  
Author(s):  
Alper Gökbulut
Keyword(s):  
Medicinal Plants ◽  
High Performance ◽  
Separation Efficiency ◽  
Rapid Development ◽  
Herbal Remedies ◽  
Qualitative And Quantitative ◽  
Powerful Analytical Tool ◽  
Quantitative Examination ◽  
Data Acquisition And Processing ◽  
Layer Chromatography

Background: Chromatographic techniques such as TLC basically and, HPLC, GC, HPTLC equipped with various detectors are most frequently used for the qualitative and quantitative examination of herbals. Method: An overview of the recent literature concerning the usage of HPTLC for the analysis of medicinal plants has been reviewed. Results: During the last decade/s, HPTLC, a modern, sophisticated and automatized TLC technique with better and advanced separation efficiency, detection limit, data acquisition and processing, has been used for the analysis of herbal materials and preparations since the rapid development of technology in chromatography world. HPTLC with various detectors is a powerful analytical tool especially for the phytochemical applications such as herbal drug quantification and fingerprint analysis. Conclusion: In this review, a latest perspective has been established and some of the previous studies were summarized for the usage of HPTLC in the analysis of herbal remedies, dietary supplements and nutraceuticals.

MAGIC-I as Assistance for the Visually Impaired People

2020 ◽  
Vol 13 ◽  
Author(s):  
Kavita Pandey ◽  
Dhiraj Pandey ◽  
Vatsalya Yadav ◽  
Shriya Vikhram
Keyword(s):  
Visually Impaired ◽  
Smart Phone ◽  
Emergency Situation ◽  
Daily Activities ◽  
Daily Life Activities ◽  
Best Friends ◽  
Visually Impaired People ◽  
The World ◽  
Impaired People ◽  
Impaired User

Background: According to the WHO report, around 4.07% of the world's population is visually impaired. About 90% of the visually impaired users live in the lower economic strata. In the fast moving technology, most of the invention misses the need of these people. Mainly the technologies were designed for mainstream people; visually impaired people always find an inability to access it. This inability arises primarily for reasons such as cost, for example, Perkins Brailler costs 80-248 dollars for the simple purpose of Braille input. Another major reason is the hassle of carrying the big equipment. Objective: Keeping all this in mind and making technology as their best friends, MAGIC-1 has been designed. The goal is to provide a solution in terms of an application, which helps the visually impaired user in their daily life activities. Method: The proposed solution assists visually impaired users through smart phone technology. If visually impaired users ever wished to have a touched guide into a smart phone, MAGIC-1 has the solution that consolidates all the important features in their daily activities. Results: The performance of the solution as a whole and its individual features in terms of usability, utility and other metrics, etc. has been tested with sample visually impaired users. Moreover, their performances in term of Errors per Word and Words per Minute have been observed. Conclusion: MAGIC-I, the proposed solution works as an assistant of visually impaired users to overcome their daily struggles and stay more connected to the world. A visually impaired user can communicate via their mobile devices with features like eyes free texting using braille, voice calling etc. They can easily take help in an emergency situation with the options of SOS emergency calling and video assistance.

Changes in the Male Reproductive Organs of the Dugong, Dugong dugon (Sirenia: Dugondidae) with Age and Reproductive Activity

1984 ◽  
Vol 32 (6) ◽  
pp. 721 ◽  
Author(s):  
H Marsh ◽  
GE Heinsohn ◽  
TD Glover
Keyword(s):  
Reproductive Tract ◽  
Prostate Gland ◽  
Reproductive Activity ◽  
Reproductive Organs ◽  
Seminal Vesicles ◽  
Growth Layer ◽  
Male Reproductive Tract ◽  
Qualitative And Quantitative ◽  
Quantitative Examination ◽  
Testicular Histology

The anatomy and histology of the male reproductive tract of the dugong (Dugong dugon) is described. Each testis and its adjacent epididymis lie immediately caudal to the corresponding kidney. The seminal vesicles are large but there is no discrete prostate gland and the bulbo-urethral glands are also diffuse. Both qualitative and quantitative examination of the testes and epididymides of 59 males whose ages have been estimated from tusk dentinal growth layer counts indicate that the male dugong does not produce spermatozoa continuously, despite the absence of a distinct breeding season. Individual dugongs were observed with testes at all stages between complete quiescence and full spermatogenesis, and only 10 of the 40 mature males had fully spermatogenic testes and epididymides packed with spermatozoa. Androgenic and spermatogenic activity of the testes appeared to be in phase, but the testicular histology of some old males suggested that they may have been sterile for long periods.

The iron content of iron superoxide dismutase: determination by anomalous scattering

1983 ◽  
Vol 218 (1210) ◽  
pp. 119-126 ◽  
Keyword(s):  
Superoxide Dismutase ◽  
Iron Content ◽  
Three Dimensional ◽  
Anomalous Scattering ◽  
Total Iron Content ◽  
Iron Site ◽  
Iron Superoxide Dismutase ◽  
Density Map ◽  
The Difference ◽  
Electron Density Map

The number of iron atoms in the dimeric iron-containing superoxide dismutase from Pseudomonas ovalis and their atomic positions have been determined directly from anomalous scattering measurements on crystals of the native enzyme. To resolve the long-standing question of the total amount of iron per molecule for this class of dismutase, the occupancy of each site was refined against the measured Bijvoet differences. The enzyme is a symmetrical dimer with one iron site in each subunit. The iron position is 9 ņ from the intersubunit interface. The total iron content of the dimer is 1.2±0.2 moles per mole of protein. This is divided between the subunits in the ratio 0.65:0.55; the difference between them is probably not significant. Since each subunit contains, on average, slightly more than half an iron atom we conclude that the normal state of this enzyme is two iron atoms per dimer but that some of the metal is lost during purification of the protein. Although the crystals are obviously a mixture of holo- and apo-enzymes, the 2.9 Å electron density map is uniformly clean, even at the iron site. We conclude that the three-dimensional structures of the iron-bound enzyme and the apoenzyme are identical.

scholarly journals The orthopedic characterization of cfap298tm304 mutants validate zebrafish to faithfully model human AIS

2021 ◽  
Vol 11 (1) ◽  
Author(s):  
Marie-Hardy Laura ◽  
Cantaut-Belarif Yasmine ◽  
Pietton Raphaël ◽  
Slimani Lotfi ◽  
Pascal-Moussellard Hugues
Keyword(s):  
Cerebrospinal Fluid ◽  
Three Dimensional ◽  
Fluid Circulation ◽  
Micro Computed Tomography ◽  
Csf Flow ◽  
Cerebrospinal Fluid Circulation ◽  
Clinical Criteria ◽  
Brain And Spinal Cord ◽  
The Brain

AbstractCerebrospinal fluid (CSF) circulation relies on the beating of motile cilia projecting in the lumen of the brain and spinal cord cavities Mutations in genes involved in cilia motility disturb cerebrospinal fluid circulation and result in scoliosis-like deformities of the spine in juvenile zebrafish. However, these defects in spine alignment have not been validated with clinical criteria used to diagnose adolescent idiopathic scoliosis (AIS). The aim of this study was to describe, using orthopaedic criteria the spinal deformities of a zebrafish mutant model of AIS targeting a gene involved in cilia polarity and motility, cfap298tm304. The zebrafish mutant line cfap298tm304, exhibiting alteration of CSF flow due to defective cilia motility, was raised to the juvenile stage. The analysis of mutant animals was based on micro-computed tomography (micro-CT), which was conducted in a QUANTUM FX CALIPER, with a 59 µm-30 mm protocol. 63% of the cfap298tm304 zebrafish analyzed presented a three-dimensional deformity of the spine, that was evolutive during the juvenile phase, more frequent in females, with a right convexity, a rotational component and involving at least one dislocation. We confirm here that cfap298tm304 scoliotic individuals display a typical AIS phenotype, with orthopedic criteria mirroring patient’s diagnosis.

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