• Journal of Photoscience
• /
• v.2 no.2
• /
• pp.63-67
• /
• 1995

Zinc plays a key role in genetic expression, cell division, and growth and is essential for the function of more than 200 enzymes; effects of zinc deficiency induce many syndromes, including abnormal visual adaptation. The pigment epithelium (EP) contains high concentrations of zinc in humans and in animals and it participates in threshold elevation, visual sensitivity increment, and acceleration of rhodopsin regeration during visual adaptation. The origin of c-wave of electroretinogram(ERG) is not only pigment epithelium as shown in present research, but also other cell layers, perhaps the photoreceptors. We propose zinc as a candidate for an internal messenger which participates in signal amplification.

• Applied Microscopy
• /
• v.47 no.4
• /
• pp.238-241
• /
• 2017

A study on the visual cell and eyeball of the endemic Korean species Liobagrus mediadiposalis was investigated by light and electron microscopes. The retina of a small and 2 mm-diameter round eye was thin, $151.0{\pm}4.0{\mu}m$ and has two visual cells, a single cone and a rod cell. The single cone cells are short and thick, $18.0{\pm}0.9{\mu}m$ in length and $5.1{\pm}0.7{\mu}m$ (n=30) in diameter, while the rod cells are longer and thinner, $54.8{\pm}2.9{\mu}m$ in length and $3.3{\pm}0.6{\mu}m$ in diameter. The cone cells are seen an irregular and random mosaic pattern, and the rod cells are also randomly situated at between cone cells. As a rare phenomenon, such structure is one of characteristics reflecting the eye of a nocturnal and bottom-dwelling freshwater fish. The ultrastructure of visual cells was observed with scanning and transmission electron microscopy, both cone and rod cells are divided into an inner segment with numerous mitochondria and an outer segment with stacks of membrane discs.

• The Korean Journal of Physiology and Pharmacology
• /
• v.13 no.3
• /
• pp.221-227
• /
• 2009

For successful restoration of visual function by a visual neural prosthesis such as retinal implant, electrical stimulation should evoke neural responses so that the informat.ion on visual input is properly represented. A stimulation strategy, which means a method for generating stimulation waveforms based on visual input, should be developed for this purpose. We proposed to use the decoding of visual input from retinal ganglion cell (RGC) responses for the evaluation of stimulus encoding strategy. This is based on the assumption that reliable encoding of visual information in RGC responses is required to enable successful visual perception. The main purpose of this study was to determine the influence of inter-dependence among stimulated RGCs activities on decoding accuracy. Light intensity variations were decoded from multiunit RGC spike trains using an optimal linear filter. More accurate decoding was possible when different types of RGCs were used together as input. Decoding accuracy was enhanced with independently firing RGCs compared to synchronously firing RGCs. This implies that stimulation of independently-firing RGCs and RGCs of different types may be beneficial for visual function restoration by retinal prosthesis.

• Proceedings of the Korea Contents Association Conference
• /
• 2003.05a
• /
• pp.351-355
• /
• 2003

Neurons in the mammalian visual cortex can be classified into the two main categories of simple cells and complex cells based on their response properties. Here, we find the complex features corresponding to the response of complex cells by applying the unsupervised independent component analysis network to input images. This result will be helpful to elucidate the information processing mechanism of neurons in primary visual cortex.

• Journal of Biomedical Engineering Research
• /
• v.22 no.4
• /
• pp.331-338
• /
• 2001

In this paper, we have proposed a new computer retina model reflecting the mechanism of transient amacrine cell on the basis of a conventional computer retina model to understand mechanism of visual information processing. The conventional computer retina model contained most of mechanism for other retina models and it was verified with the physiological data. However, we found that a conventional computer retina model doesn't have the mechanism of amacrine cell that was likely to respond to moving stimulus. In proposed model, therefore, a conventional computer model that considered from photoreceptors to bipolar cells and a new computer model that considered for transient amacrine cell and ganglion cell was combined. As we compared the physiological data with the results of computer simulation of transient amacrine cell about fixed stimulus and moving stimulus, we confirmed that the proposed new computer retina model was normally operated.

• The Journal of Bigdata
• /
• v.4 no.1
• /
• pp.53-61
• /
• 2019

The extracellular matrix, which provides the structural and biochemical support of surrounding cells, is a cell physiological modulator that controls cell division and differentiation. In the bio sector, the company produces Scapold, a three-dimensional support for tissue engineering, and cultivates stem cells in the produced Scapold to be transplanted into animals to assess tissue regeneration. This depends on components such as collagen in the tissue. Therefore, it is very important to identify the inclusion rate and distribution of components in the tissue, and the data are obtained by analyzing the color of the dyed tissue image. The process from image collection to analysis is costly, and the data collected and analyzed are managed in different formats by different research institutions. Therefore, data integration management and analysis results search are not being performed. In this paper, we establish a database that can manage relevant bigdata in an integrated manner, and propose a bio-image integrated management and retrieval system that can be searched based on color, an important analytical measure in this field of study.

• Proceedings of the Korean Society of Machine Tool Engineers Conference
• /
• 2002.04a
• /
• pp.491-495
• /
• 2002

In the paper, a Visual factory model for a optical-components manufacturing process is built. The optical-components manufacturing process is composed of 3 operation processes; optical sub assembly process, package assembly process, and fiber assembly process. Each process is managed not a batch mode, which is one of most popular manufacturing styles to produce a great deal of industrial output, but though a modular cell. In the processes, a modular cell has to be processed independently of the other cells. Optimization for the composition of assembly cell in the optical-components system is made by the Visual factory model.

• Proceedings of the Korean Society of Precision Engineering Conference
• /
• 2002.05a
• /
• pp.636-639
• /
• 2002

In the paper, a Visual factory model for a optical-components manufacturing process is built. The optical-components manufacturing process is composed of 3 operation processes; optical sub assembly process, package assembly process, and fiber assembly process. Each process is managed not a batch mode, which is one of most popular manufacturing styles to produce a great deal of industrial output, but though a modular cell. In the processes, a modular cell has to be processed independently of the other cells. Optimization for the composition of assembly cell in the optical-components system is made by the Visual factory model.

• The Journal of the Korea Contents Association
• /
• v.3 no.2
• /
• pp.19-23
• /
• 2003

Neurons in the mammalian visual cortex can be dassified into the two main categories of simple cells and complex cells based on their response properties. Here, we find the complex features corresponding to the response of complex cells by applying the unsupervised independent component analysis network to input images. This result will be helpful to elucidate the information processing mechanism of neurons in primary visual cortex.

• Applied Microscopy
• /
• v.24 no.3
• /
• pp.1-9
• /
• 1994

Pardosa astrigera possessed eight eyes arranged in three rows on the frontal carapace. A pair of small anterior lateral eyes (ALE) flanked each side by an anterior median eyes (AME) lay along the anterior margin that was situated on the anterior row of clypeus. The anterior lateral eye was composed of cornea, vitreous body, and retina. Cornea was made up mainly of exocuticle lining the cuticle. Lens in anterior lateral eye was biconvex type which bulged into the cavity of the eyecup. Outer and inner central region of lens were approximately spherical with radius of curvature $5.6{\mu}m$ and $12.5{\mu}m$, respectly. Vitreous body formed a layer between the cuticular lens and retina. They formed biconcave shape. Retina of the anterior lateral eyes was composed of three types of cells: visual cells, glia cells, and pigment cells. The visual cells were unipolar neuron, as were the receptor of the posterior lateral eye. But cell body was unique to the anterior lateral eyes. They were giant cell, relatively a few in number, and under the layer of vitreous bodies. Each visual cell healed rhabdomeres for a short stretch beneath the cell body. Rhabdomes were irregulary pattern in retina and electron dense pigment granules scattered between the rhabdomes. Glia cell situated at the cell body of visual cell and glia cell process reached to rhabdomere portion. Below the rhabdome, tapetum were about $30{\mu}m$ distance from lens, which composed of 4-5 layers. It was about $25{\mu}m$ length that intermediate segment of distal portion of visual cell. Electron dense pigment granules between the intermediate segment were observed.