• Journal of the Korean Society of Radiology
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• v.9 no.4
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• pp.213-217
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• 2015

To report problems found in a patient who has implemented stent implantation and then conducted a perfusion MRI using ASL(Arterial Spin Labeling), in order to suggest a solution to them. The perfusion MRI was conducted, using pCASL among ASL methods. Data from pCASL(Pseudo Continuous Arterial Spin Labeling) was acquired together with the structural image simply by changing position(labeling gap 15 mm, 170 mm) of the labeling pulse to avoid stent. Data was processed through the ASLtbx. When perfusion MRI was acquired using pCASL, it showed that the position of the conventional labeling pulse (labeling gap 24 mm) was overlapped with that of stent, which made signal intensity in right brain tissue appear as if it were void. When the labeling pulse was positioned (labeling gap 15 mm) to avoid stent, high signal intensity images were acquired. In labeling pulse (labeling gap 170 mm), the signal intensity was more reduced due to relaxation before labeled blood arrived at the imaging slice. pCASL can be stably repeated measurements because it does not use a contrast agent. And it should be selected with the appropriate image acquisition parameters for the high quality image.

• Progress in Medical Physics
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• v.24 no.2
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• pp.108-118
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• 2013

Currently, an arterial spin labeling (ASL) magnetic resonance imaging (MRI) technique does not routinely used in clinical studies to measure perfusion in brain because optimization of imaging protocol is required to obtain optimal perfusion signals. Therefore, the objective of this study was to investigate changes of perfusion-weighed signal intensities with varying several parameters on a pulsed arterial spin labeling MRI technique obtained from a 3T MRI system. We especially evaluated alternations of ASL-MRI signal intensities on special brain areas, including in brain tissues and lobes. The signal targeting with alternating radiofrequency (STAR) pulsed ASL method was scanned on five normal subjects (mean age: 36 years, range: 29~41 years) on a 3T MRI system. Four parameters were evaluated with varying: 1) the labeling gap, 2) the labeling delay time, 3) the labeling thickness, and 4) the slice scan order. Signal intensities were obtained from the perfusion-weighted imaging on the gray and white matters and brain lobes of the frontal, parietal, temporal, and occipital areas. The results of this study were summarized: 1) Perfusion-weighted signal intensities were decreased with increasing the labeling gap in the bilateral gray matter areas and were least affected on the parietal lobe, but most affected on the occipital lobe. 2) Perfusion-weighted signal intensities were decreased with increasing the labeling delay time until 400 ms, but increased up to 1,000 ms in the bilateral gray matter areas. 3) Perfusion-weighted signal intensities were increased with increasing the labeling thickness until 120 mm in both the gray and white matter. 4) Perfusion-weighted signal intensities were higher descending scans than asending scans in both the gray and white matter. We investigated changes of perfusion-weighted signal intensities with varying several parameters in the STAR ASL method. It should require having protocol optimization processing before applying in patients. It has limitations to apply the ASL method in the white matter on a 3T MRI system.

• Journal of Microbiology and Biotechnology
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• v.21 no.5
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• pp.477-482
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• 2011

There are accumulating evidences suggesting that connexin (Cx), a gap junction channel-forming protein, acts as a growth suppressor in various cancer cells, and this effect is attributeed to the gap junction-mediated intercellular communication (GJIC). In order to characterize the relationship between the growth-arresting activity of Cx26 and its cytoplasmic localizations after expression, we linked a nuclear export signal (NES) sequence to Cx26 cDNA before transfecting into a rat breast cancer cell line. A confocal fluorescent microscopic observation revealed that the insertion of NES minimized the nuclear expression of Cx26, and increased its cytoplasmic expression, including plasma membrane junctions. Total cell counting and BrdUrd-labeling experiments showed that the growth of the breast cancer cells was inhibited by 74% upon transfection of Cx26-NES, whereas only 9% inhibition was observed with only Cx26 cDNA.

• The Journal of The Korea Institute of Intelligent Transport Systems
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• v.16 no.6
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• pp.90-100
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• 2017

The purpose of this study is to detect and label the vehicles using the drone images as a way to overcome the limitation of the existing point and section detection system and vehicle gap estimation on Arterial road. In order to select the appropriate time zone, position, and altitude for the acquisition of the drone image data, the final image data was acquired by shooting under various conditions. The vehicle was detected by applying mixed Gaussian, image binarization and morphology among various image analysis techniques, and the vehicle was labeled by applying Kalman filter. As a result of the labeling rate analysis, it was confirmed that the vehicle labeling rate is 65% by detecting 185 out of 285 vehicles. The gap was calculated by pixel unitization, and the results were verified through comparison and analysis with Daum maps. As a result, the gap error was less than 5m and the mean error was 1.67m with the preceding vehicle and 1.1m with the following vehicle. The gaps estimated in this study can be used as the density of the urban roads and the criteria for judging the service level.

• Progress in Medical Physics
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• v.18 no.1
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• pp.35-41
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• 2007

In this work practical considerations of a pulsed arterial spin labeling MRI are presented to reliable multi-slice perfusion measurements In the human brain. Three parameters were considered in this study. First, In order to improve slice profile and Inversion efficiency of a labeling pulse a high power Inversion pulse of adiabatic hyperbolic secant was designed. A $900^{\circ}$ rotation of the flip angle was provided to make a good slice profile and excellent Inversion efficiency. Second, to minimize contributions of a residual magnetization be4ween Interleaved scans of control and labeling we tested three different conditions which were applied 1) only saturation pulses, 2) only spotter gradients, and 3) combinations of saturation pulses and spotter gradients Applications of bo4h saturation pulses and spoiler gradients minimized the residual magnetization. Finally, to find a minimum gap between a tagged plane and an imaging plane we tested signal changes of the subtracted image between control and labeled Images with varying the gap. The optimum gap was about 20mm. In conclusion, In order to obtain high quality of perfusion Images In human brain It Is Important to use optimum parameters. Before routinely using In clinical studios, we recommend to make optimizations of sequence parameters.

• Transactions of the Korean Society of Mechanical Engineers A
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• v.28 no.12
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• pp.1997-2003
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• 2004

This paper presents a new method and an associated device, capable of detecting protein presence and size from the shift of the mechanical stiffness changing points due to the presence and size of proteins in a nano-gap actuator. Compared to the conventional resonant detection method, the present nanomechanical stiffness detection method shows higher precision for protein detection. The present method also offers simple and inexpensive protein detection devices by removing labeling process and optical components. We design and fabricate the nanomechanical protein detector using an electrothermal actuator with a nano-gap. In the experimental study, we measure the stiffness changing points and their coordinate shift from the devices with and without target proteins. The fabricated device detects the protein presence and the protein size of 14.0$\pm$7.4nm based on the coordinate shift of stiffness changing points. We experimentally verify the protein presence and size detection capability of the nanomechanical protein detector for applications to high-precision biomolecule detection.

• Journal of Ginseng Research
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• v.19 no.3
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• pp.267-274
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• 1995

Vicilin and legumin, the storage Proteins of seed, were Purified from ginseng (Panax ginseng C.A. Meyer) endosperm cells. They were immunized in rabbits, and antibodies were raised respectively. Using these two antibodies, double immunogold labeling of vicilin and legumin was carried out to determine the gap of synthetic time and the transport pattern of vicilin and legumin in the ginseng endosperm cells. Vicilin and legumin were synthesized at the same time at early embryo developmental stage. They were secreted from the Golgi bodies and accumulated into the small vacuoles. As the endosperm cells developed, vicilin and legumin localized in the small vacuoles were gradually transported toward the large central vacuole where they were stored. Protein bodies were derived from the vacuoles filled with proteins and distributed in the endosperm cells of mature red seed. Protein bodies were various in size from 1 to 8 ${\mu}{\textrm}{m}$ in which vicilin and legumin were mixed each other. The number of small particles labeled on the vicilin was greater than that of large particles labeled on the legumin in the protein bodies indicating that the amount of vicilin is higher than that of legumin in the protein bodies.

• Journal of information and communication convergence engineering
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• v.22 no.1
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• pp.56-63
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• 2024

Despite the rapid strides in content-based image retrieval, a notable disparity persists between the visual features of images and the semantic features discerned by humans. Hence, image retrieval based on the association of semantic similarities recognized by humans with visual similarities is a difficult task for most image-retrieval systems. Our study endeavors to bridge this gap by refining image semantics, aligning them more closely with human perception. Deep learning techniques are used to semantically classify images and retrieve those that are semantically similar to personalized images. Moreover, we introduce a keyword-based image retrieval, enabling automatic labeling of images in mobile environments. The proposed approach can improve the performance of a mobile device with limited resources and bandwidth by performing retrieval based on the visual features and keywords of the image on the mobile device.

• Nuclear Engineering and Technology
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• v.50 no.8
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• pp.1355-1363
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• 2018

Many radionuclides exist in normal environment and artificial radionuclides also can be detected. The radionuclides ($^{131}I$) are widely used for labeling compounds and radiation therapy. In Korea, the radionuclide ($^{131}I$) is produced at the Radioisotope Production Facility (RIPF) at the Korea Atomic Energy Research Institute in Daejeon. The residents around the RIPF assume that $^{131}I$ detected in environmental samples is produced from RIPF. To ensure the safety of the residents, the radioactive concentration of $^{131}I$ near the RIPF was investigated by monitoring environmental samples along the Gap River. The selected geographical places are near the nuclear installation, another possible location for $^{131}I$ detection, and downstream of the Gap River. The first selected places are the "front gate of KAERI", and the "Donghwa bridge". The second selected place is the sewage treatment plant. Therefore, the Wonchon bridge is selected for the upstream of the plant and the sewage treatment plant is selected for the downstream of the plant. The last selected places are the downstream where the two paths converged, which is Yongshin bridge (in front of the cogeneration plant). In these places, environmental samples, including sediment, fish, surface water, and aquatic plants, were collected. In this study, the radioactive iodine ($^{131}I$) detection along the Gap River will be investigated.

• Journal of Environmental Health Sciences
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• v.45 no.5
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• pp.443-456
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• 2019

Objectives: Children are exposed to various environmental pollutants through contact with children's products. We investigated the KC mark, certification number, and contained substances labeled on children's products through market research and collected the toxicological data on these substances. Methods: The environmentally hazardous substances labeled on children's products (n=6576), including toys (n=2812), personal care products (n=2212), stationary/books (n=1333), and playground equipment (n=219) were examined. For the components that could be identified by CAS number, toxicological data on oral, inhalation, and dermal routes, cancer slope factor, and reference dose were collected. Results: Among the investigated products, KC marks or certification numbers were found for 4557 products (69.3%). Except for cosmetics and cleansers, the material information was labeled on most of the products. The frequency of labeling substance information in toys and stationary/books was low since this information could be omitted if KC certification was obtained. In the target products, 617 substances were identified by CAS number, and polypropylene, acrylonitrile butadiene styrene, and polyester were the most frequently displayed. Chronic toxicity data was found for only 32.4% of individual components, and information on toxicity through the dermal route was also highly limited. Conclusion: Our study suggested that labeling guidelines should be required to identify the environmentally hazardous substances contained in children's products. In addition, the toxicological data on many ingredients in children's products were insufficient. The data gap for toxicity data should be filled for future risk assessment.