• Journal of the Korean Society of Visualization
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• v.21 no.2
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• pp.14-23
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• 2023

The pressure difference across stenotic blood vessels is a commonly used clinical metric for diagnosing many cardiovascular diseases. At present, most clinical pressure measurements rely solely on invasive catheterization. In this study, we propose a novel method for non-invasive pressure estimation using the incompressible Navier-Stokes equations and a 3D multi-path integration approach. We verify spatio-temporal convergence on an in-silico dataset of a cylindrical straight pipe phantom with steady and pulsatile flow fields. We then evaluate the proposed method on an in vitro dataset of reconstructed control, pre-operative, and post-operative carotid artery cases acquired from 4D flow MRI. The performance of our method is compared to existing approaches based on the pressure Poisson equation and work-energy relative pressure. The results demonstrate the proposed method's high accuracy, robustness to spatio-temporal subsampling, and reduced sensitivity to noise, highlighting its great potential for non-invasive pressure estimation.

• Journal of Biomedical Engineering Research
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• v.28 no.5
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• pp.676-683
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• 2007

A non-invasive respiratory gated radiotherapy system like those based on external anatomic motion gives better comfortableness to patients than invasive system on treatment. However, higher correlation between the external and internal anatomic motion is required to increase the effectiveness of non-invasive respiratory gated radiotherapy. Both of invasive and non-invasive methods need to track the internal anatomy with the higher precision and rapid response. Especially, the non-invasive method has more difficulty to track the target position successively because of using only image processing. So we developed the system to track the motion for a non-invasive respiratory gated system to accurately find the dynamic position of internal structures such as the diaphragm and tumor. The respiratory organ motion tracking apparatus consists of an image capture board, a fluoroscopy system and a processing computer. After the image board grabs the motion of internal anatomy through the fluoroscopy system, the computer acquires the organ motion tracking data by image processing without any additional physical markers. The patients breathe freely without any forced breath control and coaching, when this experiment was performed. The developed pattern-recognition software could extract the target motion signal in real-time from the acquired fluoroscopic images. The range of mean deviations between the real and acquired target positions was measured for some sample structures in an anatomical model phantom. The mean and max deviation between the real and acquired positions were less than 1mm and 2mm respectively with the standardized movement using a moving stage and an anatomical model phantom. Under the real human body, the mean and maximum distance of the peak to trough was measured 23.5mm and 55.1mm respectively for 13 patients' diaphragm motion. The acquired respiration profile showed that human expiration period was longer than the inspiration period. The above results could be applied to respiratory-gated radiotherapy.

• Journal of The Korean Society of Integrative Medicine
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• v.4 no.4
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• pp.77-82
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• 2016

Purpose: The purpose of this study was to investigate the therapeutic effect of non-invasive vagus nerve stimulation by transcutaneous electrical nerve stimulation application on the autonomic nervous system of human body. Methods: Participants were seventeen healthy adults. Standard deviation of all normal N-N intervals(SDNN), root mean square of successive differences(RMSSD), low frequency(LF), high frequency(HF) were compared in pre and post Mean values after intervention. Data were analyzed in Wilcoxon's signed-ranks test. Results: The results of this study is that sistolic blood pressure and pulse rate decreased mean value after non-invasive vagus nerve stimulation by transcutaneous electrical nerve stimulation. High frequency, low frequency, SDNN, RMSSD increased mean value in heart rate variability after intervention. But that is not significant except for SDNN. Conclusion: Non-invasive vagus stimulation by transcutaneous electrical nerve stimulation effect on parasympathetic nerve stimulation, and then it might be effective method for autonomic nerve balance control.

• Proceedings of the National Institute of Ecology of the Republic of Korea
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• v.4 no.4
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• pp.154-158
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• 2023

The Asiatic black bear, Ursus thibetanus, is among the most threatened or endangered species in Asia. For its conservation and management, sex identification of U. thibetanus using non-invasive samples (e.g., hair and/or feces) is potentially valuable. In this study, a non-invasive molecular method for sex identification of U. thibetanus samples collected from various countries was first utilized, and it was based on polymerase chain reaction (PCR) amplification of the amelogenin gene via PCRs. Thirty-three bear DNA samples, extracted not only from blood (n=9) but also from hair (n=18) and feces (n=6), were used. We performed sex-specific PCR amplifications of the amelogenin gene using a primer set, SE47 and SE48. The primer set could successfully amplify a single X-specific band for females and both X- and Y-specific bands for males from all blood (100%) and hair (100%) samples. In addition, the primer set could distinguish the sex of bears in four out of a total of six fecal samples (approximately 67%). This study's findings suggest that this molecular method can be applied to sex identification of Asiatic black bears from various Asian regions using non-invasive samples, such as hair and feces.

• Proceedings of the Korean Institute of Information and Commucation Sciences Conference
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• 2016.10a
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• pp.105-108
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• 2016

Shipping Along with the aging of the total population, its importance is greater cause of stroke, which is one of the diseases are listed cerebral perfusion is about 80%,.ie that the flow of blood flowing to the brain is reduced as the cause. One of the most typical prophylaxis and treatment of these stroke is to enhance cerebral perfusion. However, since the method of enhancing conventional cerebral perfusion have been conducted mainly in invasive method, giving a burden to the patient, the problem of inducing a number of complications were noted. Therefore, in this paper, an attempt to supplement the shortcomings of such invasive brain perfusion increase method, to provide a device to enhance the non-invasively brain perfusion.

• Journal of fish pathology
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• v.37 no.1
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• pp.89-96
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• 2024

Kudoa septempunctata, a myxozoan parasite, usually presents without any signs and primarily infects adult fish. The invasive diagnostic methods, such as tissue biopsy, can identify pathogens, but cause economic losses because they require killing the fish. In this study, we conducted a monitoring of four fish farms located on Jeju Island, to investigate the potential for non-invasive diagnosis of K. septempunctata using hyperspectral cameras. It provides spectral information from R000_B000_G000 to R255_B255_G255 for a total of 3,282 olive flounder (Paralichthys olivaceus). Each object is imaged with 2,000 data points, allowing comprehensive spectral analysis by comparing images obtained from negative control objects to positive control objects. Noticeable differences were observed in the brightness or pallor of the positive control images. This suggests the potential utility of hyperspectral imaging as a non-invasive diagnostic tool for detecting K. septempunctata infections in fish populations.

• Journal of Photoscience
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• v.10 no.2
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• pp.215-216
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• 2003

SPEX SkinSkan is a newly developed spectrofluorometer that can calculate transmission of UVA on the surface of human skin as a non-invasive method. We have investigated UVA protection factors of Japanese over-the-counter sunscreens using SPEX SkinSkan. This non-invasive method is useful to know UVA protection of sunscreens in vivo.

• Sleep Medicine and Psychophysiology
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• v.28 no.2
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• pp.53-69
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• 2021

Sleep disorders, increasingly prevalent in the general population, induce impairment in daytime functioning and other clinical problems. As changes in cortical excitability have been reported as potential pathophysiological mechanisms underlying sleep disorders, multiple studies have explored clinical effects of modulating cortical excitability through non-invasive brain stimulation in treating sleep disorders. In this study, we critically reviewed clinical studies using non-invasive brain stimulation, particularly transcranial magnetic stimulation (TMS) and transcranial direct current stimulation (tDCS), for treatment of sleep disorders. Previous studies have reported inconsistent therapeutic effects of TMS and tDCS for various kinds of sleep disorders. Specifically, low-frequency repetitive TMS (rTMS) and cathodal tDCS, both of which exert an inhibitory effect on cortical excitability, have shown inconsistent therapeutic effects for insomnia. On the other hand, high-frequency rTMS and anodal tDCS, both of which facilitate cortical excitability, have improved the symptoms of hypersomnia. In studies of restless legs syndrome, high-frequency rTMS and anodal tDCS induced inconsistent therapeutic effects. Single TMS and rTMS have shown differential therapeutic effects for obstructive sleep apnea. These inconsistent findings indicate that the distinctive characteristics of each non-invasive brain stimulation method and specific pathophysiological mechanisms underlying particular sleep disorders should be considered in an integrated manner for treatment of various sleep disorders. Future studies are needed to provide optimized TMS and tDCS protocols for each sleep disorder, considering distinctive effects of non-invasive brain stimulation and pathophysiology of each sleep disorder.

• Journal of IKEEE
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• v.24 no.3
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• pp.713-718
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• 2020

The method of measuring skin active points is a technique for obtaining a lot of biometric information because it is measured with convenience, low cost and non-invasive methods. In this paper, we used in a three electrode measure method that has the advantage of measuring the impedance of the APs under the skin. The impedance measuring method is well illustrated by a simple model of an equivalent electrical circuit that correlates well with experimental results. The characteristic frequencies of APs are about 15-30HZ higher than that of surrounding skin and the values of measured reactance are about 35-77KΩ smaller. This technology analyzed accurately and objectively the reactance and characteristic frequency of APs and the surrounding skin using a non-invasive measuring system.

• Asian Pacific Journal of Cancer Prevention
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• v.16 no.2
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• pp.657-660
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• 2015

Background: A diagnosis of H. pylori infection can be made by invasive or non-invasive methods. Several noninvasive diagnostic tests based on the detection of H. pylori stool antigen (HpSA) have been developed. The Genx H. pylori stool antigen card test is a new rapid, non-invasive test that is based on monoclonal immunochromatographic assay. The aim of this study was to determine its sensitivity, specificity, and diagnostic accuracy for diagnosing H. pylori infection in adult patients. Materials and Methods: A total of 162 patients were included in the study. A gastric biopsy was collected for histopathology and rapid urease testing. Stool specimens for HpSA testing were also collected. Patients were considered H. pylori positive if two invasive tests (histological and rapid urease tests) were positive. Results: Using the reference test, 50.6% of the samples were positive for H. pylori infection. The Genx H. pylori antigen test was positive in 19.7% of patients. The sensitivity, specificity, positive predictive value, negative predictive value, and diagnostic accuracy of the Genx H. pylori antigen test were 51.6%, 96.0%, 88.8%, 76.1%, and 79.0%, respectively. Conclusions: The Genx H. pylori stool antigen card test is a new non-invasive method that is fast and simple to perform but provides less reliable results.