https://scholar.dgist.ac.kr/handle/20.500.11750/13573 2026-04-04T14:14:45Z https://scholar.dgist.ac.kr/handle/20.500.11750/59974 Title: Diffuse speckle contrast analysis for flowmetry with deep light sources Author(s): Jang, Seo Won; Moon, Soomin; Park, Jae Yoon; Lee, Tae Gyun; Lee, Kijoon Abstract: Diffuse optical probes for monitoring various hemodynamic variables usually use tissue-contacting fiber based probes, and no practical cases exist where source location is positioned in deep tissue, as diffuse optical spectroscopy and tomography are normally regarded as a non-invasive imaging technique. There are some cases, however, where the light source is positioned in deep tissue, as in the case of recently developed laser acupuncture. In this study, we theoretically analyze the light propagation in a semi-infinite diffuse medium with a deep light source, especially in the context of blood flow measurement. A liquid phantom study with deep light sources is performed to validate the analytic solution of photon diffusion equation, and a diffuse speckle contrast analysis (DSCA) measurement from a flow phantom within a solid matrix is performed to demonstrate the feasibility of the proposed method. The results show that the flow measurement using DSCA with a deep light source is not only feasible, but also has advantages in some cases. Sensitivity analysis shows the light source with a depth of up to 2 cm can be used to provide the information on the magnitude and location of blood flow. 2026-02-28T15:00:00Z https://scholar.dgist.ac.kr/handle/20.500.11750/47504 Title: Pressure stimulus study on acupuncture points with multi-channel multimode-fiber diffuse speckle contrast analysis (MMF-DSCA) Author(s): Park, Jae Yoon; Choi, Gisoon; Lee, Kijoon Abstract: A multi-channel multimode-fiber deep tissue flowmetry system has been constructed based on diffuse speckle contrast analysis (DSCA) for simultaneous blood flow measurements at different locations on the human body. This system has been utilized in an acupuncture study within the field of traditional Chinese medicine (TCM), primarily focusing on acupuncture points along the large intestine meridian. Deep tissue blood flow was monitored at four different acupuncture points (LI1, LI5, LI10, and ST25) with a sampling rate of 60 Hz while applying pressure stimulus on LI4 (hegu or hapgok). Although the blood flow index (BFI) and blood volume (BV) did not exhibit significant changes after the pressure stimulus, an increase in the amplitude and complexity of low-frequency oscillations (LFOs) in microcirculation was observed. © 2023 Optica Publishing Group under the terms of the Optica Open Access Publishing Agreement. 2023-10-31T15:00:00Z https://scholar.dgist.ac.kr/handle/20.500.11750/17348 Title: Dataset on transcriptome signature of skeletal muscle of young, adult and aged mice Author(s): Listrat, Anne; Goh, Kheng Lim; Jousse, Celine; Tounayre, Jeremy; Wang, Huijuan; Lee, Kijoon; Bechet, Daniel Abstract: This data article reports the level of expression of messenger RNA (mRNA) obtained from a set of 18 skeletal muscle samples using Affymetrix Genechips Exon arrays. Data were obtained from Gastrocnemius muscle of C57BL6 male mice at 3 distinct age groups, 2, 11 and 25 months old representing young, mature adult and aged groups. The data submitted to GEO constitute a large dataset of 15,300 mRNA levels. The data include eighteen .CEL files obtained after scanning mouse exon arrays and one .xls file obtained after processing with Genespring GX 14.9. Three distinct files containing affymetrix data processed using Genespring and analyzed for differences between stages 2 per 2 are provided as supplementary data. © 2022 The Authors. Published by Elsevier Inc. 2022-07-31T15:00:00Z https://scholar.dgist.ac.kr/handle/20.500.11750/16817 Title: Blood flow estimation via numerical integration of temporal autocorrelation function in diffuse correlation spectroscopy Author(s): Seong, Myeongsu; Oh, Yoonho; Lee, Kijoon; Kim, Jae G. Abstract: Background and Objective: Diffuse correlation spectroscopy (DCS) is an optical technique widely used to monitor blood flow. Recently, efforts have been made to derive new signal processing methods to minimize the systems used and shorten the signal processing time. Herein, we propose alternative approaches to obtain blood flow information via DCS by numerically integrating the temporal autocorrelation curves. Methods: We use the following methods: the inverse of K2 (IK2)—based on the framework of diffuse speckle contrast analysis—and the inverse of the numerical integration of squared g1 (INISg1) which, based on the normalized electric field autocorrelation curve, is more simplified than IK2. In addition, g1 thresholding is introduced to further reduce computational time and make the suggested methods comparable to the conventional nonlinear fitting approach. To validate the feasibility of the suggested methods, studies using simulation, liquid phantom, and in vivo settings were performed. In the meantime, the suggested methods were implemented and tested on three types of Arduino (Arduino Due, Arduino Nano 33 BLE Sense, and Portenta H7) to demonstrate the possibility of miniaturizing the DCS systems using microcotrollers for signal processing. Results: The simulation and experimental results confirm that both IK2 and INISg1 are sufficiently relevant to capture the changes in blood flow information. More interestingly, when g1 thresholding was applied, our results showed that INISg1 outperformed IK2. It was further confirmed that INISg1 with g1 thresholding implemented on a PC and Portenta H7, an advanced Arduino board, performed faster than did the deep learning-based, state-of-the-art processing method. Conclusion: Our findings strongly indicate that INISg1 with g1 thresholding could be an alternative approach to derive relative blood flow information via DCS, which may contribute to the simplification of DCS methodologies. © 2022 The Authors. Published by Elsevier B.V. 2022-06-30T15:00:00Z