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Cha MY, Hong YJ, Choi JE, Kwon TS, Kim IJ, Hong KW. Classification of early age facial growth pattern and identification of the genetic basis in two Korean populations. Sci Rep 2022; 12:13828. [PMID: 35970861 PMCID: PMC9378761 DOI: 10.1038/s41598-022-18127-6] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/22/2021] [Accepted: 08/05/2022] [Indexed: 11/11/2022] Open
Abstract
Childhood to adolescence is an accelerated growth period, and genetic features can influence differences of individual growth patterns. In this study, we examined the genetic basis of early age facial growth (EAFG) patterns. Facial shape phenotypes were defined using facial landmark distances, identifying five growth patterns: continued-decrease, decrease-to-increase, constant, increase-to-decrease, and continued-increase. We conducted genome-wide association studies (GWAS) for 10 horizontal and 11 vertical phenotypes. The most significant association for horizontal phenotypes was rs610831 (TRIM29; β = 0.92, p-value = 1.9 × 10−9) and for vertical phenotypes was rs6898746 (ZSWIM6; β = 0.1103, p-value = 2.5 × 10−8). It is highly correlated with genes already reported for facial growth. This study is the first to classify and characterize facial growth patterns and related genetic polymorphisms.
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Cho H, Park H, Kim IJ, Cho J. Data Augmentation of Backscatter X-ray Images for Deep Learning-Based Automatic Cargo Inspection. SENSORS (BASEL, SWITZERLAND) 2021; 21:7294. [PMID: 34770600 PMCID: PMC8587046 DOI: 10.3390/s21217294] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 09/22/2021] [Revised: 10/21/2021] [Accepted: 10/26/2021] [Indexed: 11/24/2022]
Abstract
Custom inspection using X-ray imaging is a very promising application of modern pattern recognition technology. However, the lack of data or renewal of tariff items makes the application of such technology difficult. In this paper, we present a data augmentation technique based on a new image-to-image translation method to deal with these difficulties. Unlike the conventional methods that convert a semantic label image into a realistic image, the proposed method takes a texture map with a special modification as an additional input of a generative adversarial network to reproduce domain-specific characteristics, such as background clutter or sensor-specific noise patterns. The proposed method was validated by applying it to backscatter X-ray (BSX) vehicle data augmentation. The Fréchet inception distance (FID) of the result indicates the visual quality of the translated image was significantly improved from the baseline when the texture parameters were used. Additionally, in terms of data augmentation, the experimental results of classification, segmentation, and detection show that the use of the translated image data, along with the real data consistently, improved the performance of the trained models. Our findings show that detailed depiction of the texture in translated images is crucial for data augmentation. Considering the comparatively few studies that have examined custom inspections of container scale goods, such as cars, we believe that this study will facilitate research on the automation of container screening, and the security of aviation and ports.
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Yang Y, Kim H, Choi H, Chae S, Kim IJ. Scene Adaptive Online Surveillance Video Synopsis via Dynamic Tube Rearrangement Using Octree. IEEE TRANSACTIONS ON IMAGE PROCESSING : A PUBLICATION OF THE IEEE SIGNAL PROCESSING SOCIETY 2021; 30:8318-8331. [PMID: 34587008 DOI: 10.1109/tip.2021.3114986] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/13/2023]
Abstract
Visual surveillance produces a significant amount of raw video data that can be time consuming to browse and analyze. In this work, we present a video synopsis methodology called "scene adaptive online video synopsis via dynamic tube rearrangement using octree (SSOcT)" that can effectively condense input surveillance videos. Our method entailed summarizing the input video by analyzing scene characteristics and determining an effective spatio-temporal 3D structure for video synopsis. For this purpose, we first analyzed the attributes of each extracted tube with respect to scene geometry and complexity. Then, we adaptively grouped the tubes using an online grouping algorithm that exploits these scene characteristics. Finally, the tube groups were dynamically rearranged using the proposed octree-based algorithm that efficiently inserted and refined tubes containing high spatio-temporal movements in real time. Extensive video synopsis experimental results are provided, demonstrating the effectiveness and efficiency of our method in summarizing real-world surveillance videos with diverse scene characteristics.
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Kim YM, Ryu S, Kim IJ. Planar Abstraction and Inverse Rendering of 3D Indoor Environments. IEEE TRANSACTIONS ON VISUALIZATION AND COMPUTER GRAPHICS 2021; 27:2992-3006. [PMID: 31869795 DOI: 10.1109/tvcg.2019.2960776] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/10/2023]
Abstract
Scanning and acquiring a 3D indoor environment suffers from complex occlusions and misalignment errors. The reconstruction obtained from an RGB-D scanner contains holes in geometry and ghosting in texture. These are easily noticeable and cannot be considered as visually compelling VR content without further processing. On the other hand, the well-known Manhattan World priors successfully recreate relatively simple structures. In this article, we would like to push the limit of planar representation in indoor environments. Given an initial 3D reconstruction captured by an RGB-D sensor, we use planes not only to represent the environment geometrically but also to solve an inverse rendering problem considering texture and light. The complex process of shape inference and intrinsic imaging is greatly simplified with the help of detected planes and yet produces a realistic 3D indoor environment. The generated content can adequately represent the spatial arrangements for various AR/VR applications and can be readily composited with virtual objects possessing plausible lighting and texture.
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Hong YJ, Choi SE, Nam GP, Choi H, Cho J, Kim IJ. Adaptive 3D Model-Based Facial Expression Synthesis and Pose Frontalization. SENSORS (BASEL, SWITZERLAND) 2020; 20:E2578. [PMID: 32369980 PMCID: PMC7248866 DOI: 10.3390/s20092578] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 04/01/2020] [Revised: 04/26/2020] [Accepted: 04/28/2020] [Indexed: 11/21/2022]
Abstract
Facial expressions are one of the important non-verbal ways used to understand human emotions during communication. Thus, acquiring and reproducing facial expressions is helpful in analyzing human emotional states. However, owing to complex and subtle facial muscle movements, facial expression modeling from images with face poses is difficult to achieve. To handle this issue, we present a method for acquiring facial expressions from a non-frontal single photograph using a 3D-aided approach. In addition, we propose a contour-fitting method that improves the modeling accuracy by automatically rearranging 3D contour landmarks corresponding to fixed 2D image landmarks. The acquired facial expression input can be parametrically manipulated to create various facial expressions through a blendshape or expression transfer based on the FACS (Facial Action Coding System). To achieve a realistic facial expression synthesis, we propose an exemplar-texture wrinkle synthesis method that extracts and synthesizes appropriate expression wrinkles according to the target expression. To do so, we constructed a wrinkle table of various facial expressions from 400 people. As one of the applications, we proved that the expression-pose synthesis method is suitable for expression-invariant face recognition through a quantitative evaluation, and showed the effectiveness based on a qualitative evaluation. We expect our system to be a benefit to various fields such as face recognition, HCI, and data augmentation for deep learning.
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Lee HY, Cha S, Ban HJ, Kim IY, Park BR, Kim IJ, Hong KW. The age distribution of facial metrics in two large Korean populations. Sci Rep 2019; 9:14564. [PMID: 31601901 PMCID: PMC6786987 DOI: 10.1038/s41598-019-51121-z] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/29/2019] [Accepted: 09/25/2019] [Indexed: 11/19/2022] Open
Abstract
Growth and alterations in craniofacial morphology have attracted interest in many fields of science, especially physical anthropology, genetics and forensic sciences. We performed an analysis of craniofacial morphology alterations by gender and ageing stage in Korean populations. We studied 15 facial metrics using two large Korean populations (1,926 samples from the Korea Medicine Data Center cohort and 5,643 samples from the Ansan-Ansung cohort). Among the 15 metrics, 12 showed gender differences and tended to change with age. In both of the independent populations, brow ridge height, upper lip height, nasal tip height, and profile nasal length tended to increase with age, whereas outer canthal width, right palpebral fissure height, left palpebral fissure height, right upper lip thickness, left upper lip thickness, nasal tip protrusion, facial base width, and lower facial width tended to decrease. In conclusion, our findings suggest that ageing (past 40 years of age) might affect eye size, nose length, upper lip thickness, and facial width, possibly due to loss of elasticity in the face. Therefore, these facial metric changes could be applied to individual age prediction and aesthetic facial care.
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Lee HY, Cha S, Ban HJ, Kim IY, Park BR, Kim IJ, Hong KW. The age distribution of facial metrics in two large Korean populations. Sci Rep 2019. [PMID: 31601901 DOI: 10.1038/s41598-019-51121-z.pmid:31601901;pmcid:pmc6786987] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/24/2023] Open
Abstract
Growth and alterations in craniofacial morphology have attracted interest in many fields of science, especially physical anthropology, genetics and forensic sciences. We performed an analysis of craniofacial morphology alterations by gender and ageing stage in Korean populations. We studied 15 facial metrics using two large Korean populations (1,926 samples from the Korea Medicine Data Center cohort and 5,643 samples from the Ansan-Ansung cohort). Among the 15 metrics, 12 showed gender differences and tended to change with age. In both of the independent populations, brow ridge height, upper lip height, nasal tip height, and profile nasal length tended to increase with age, whereas outer canthal width, right palpebral fissure height, left palpebral fissure height, right upper lip thickness, left upper lip thickness, nasal tip protrusion, facial base width, and lower facial width tended to decrease. In conclusion, our findings suggest that ageing (past 40 years of age) might affect eye size, nose length, upper lip thickness, and facial width, possibly due to loss of elasticity in the face. Therefore, these facial metric changes could be applied to individual age prediction and aesthetic facial care.
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Olšovcová V, Versaci R, Ambrožová I, Zelenka Z, Kaufman J, Margarone D, Kim IJ, Jeong TM. RESPONSE OF DOSEMETERS IN FIELDS GENERATED BY LASER-ACCELERATED PROTONS. RADIATION PROTECTION DOSIMETRY 2016; 170:318-321. [PMID: 26979806 DOI: 10.1093/rpd/ncw037] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/05/2023]
Abstract
In laser-driven acceleration, ultra-short and intense laser pulses are focussed on targets to generate beams of ionising radiation. One of the most important issues to be addressed is personal monitoring. While traditional dosemeters were designed primarily for measurements in continuous fields, dosemeters for laser laboratories must be capable of working in pulsed fields of pulse length below 1 ps, in a single-shot regime up to the repetition rate of 1 kHz. Responses of conventional dosemeters (films, polyallyldiglycol carbonate, electronic personal dosemeter) to proton bunches of up to 30 MeV energy produced by South Korean PW laser system at the Advanced Photonics Research Institute, Gwangju Institute of Science and Technology were studied, both by means of Monte Carlo simulations and experimentally.
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Jeon YK, Shin MJ, Kim MH, Mok JH, Kim SS, Kim BH, Kim SJ, Kim YK, Chang JH, Shin YB, Kim IJ. Low pulmonary function is related with a high risk of sarcopenia in community-dwelling older adults: the Korea National Health and Nutrition Examination Survey (KNHANES) 2008-2011. Osteoporos Int 2015; 26:2423-9. [PMID: 25956284 DOI: 10.1007/s00198-015-3152-8] [Citation(s) in RCA: 58] [Impact Index Per Article: 6.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 11/17/2014] [Accepted: 04/26/2015] [Indexed: 01/06/2023]
Abstract
UNLABELLED Sarcopenia is the age-related reduction of skeletal muscle mass in older individuals. Respiratory muscle strength may be related to skeletal muscle mass and, thus, the present study attempted to estimate the risk of sarcopenia relative to decreased pulmonary function. The present findings demonstrated that low pulmonary function was associated with low muscle mass in community-dwelling older adults. INTRODUCTION Lean body mass is related to pulmonary function in patients with chronic obstructive pulmonary disease (COPD). However, the relationship between muscle mass and pulmonary function in healthy older adults has yet to be clarified. Thus, the present study investigated the association of pulmonary function with muscle mass in an older community-dwelling Korean population. METHODS This study included 463 disease-free subjects over 65 years of age who underwent anthropometric measurements, laboratory tests, spirometry, and the estimation of appendicular skeletal muscle (ASM) mass in the 2008-2011 Korea National Health and Nutrition Examination Survey (KNHANES). Low muscle mass was defined as the value of ASM divided by height squared (ASM/height(2)) that was less than two standard deviations (SD) below the sex-specific mean of the young reference group. RESULTS Forced expiratory volume in 1 s (FEV1[L]) and forced vital capacity (FVC[L]) were positively correlated with ASM/height(2) in males (p < 0.001 and p = 0.001, respectively) but not in females (p = 0.360 and p = 0.779, respectively). A univariate logistic regression analysis revealed that males with low FEV1 or FVC were more likely to have low muscle mass (odds ratio [OR] = 3.11, 95% confidence interval [CI] 1.62-5.99 for FEV1; OR = 1.99, 95% CI 1.13-3.53 for FVC); similar results were found for females, but the significance was lower (OR = 11.37, 95% CI 0.97-132.91 for FEV1; OR = 7.31, 95% CI 1.25-42.74 for FVC). After adjusting for age, smoking, and moderate physical activity, a low FEV1 value was associated with low muscle mass in both males (OR = 2.90, 95% CI 1.50-5.63) and females (OR = 9.15, 95% CI 1.53-54.77). CONCLUSIONS Using nationally representative data from the 2008-2011 KNHANES, low pulmonary function was found to be associated with low muscle mass in community-dwelling older Korean adults.
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Jeon YK, Shin MJ, Kim WJ, Kim SS, Kim BH, Kim SJ, Kim YK, Shin YB, Kim IJ. The relationship between pulmonary function and bone mineral density in healthy nonsmoking women: the Korean National Health and Nutrition Examination Survey (KNHANES) 2010. Osteoporos Int 2014; 25:1571-6. [PMID: 24577346 DOI: 10.1007/s00198-014-2627-3] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 11/07/2013] [Accepted: 01/20/2014] [Indexed: 10/25/2022]
Abstract
UNLABELLED The aim of this study was to examine the association between pulmonary function and bone mineral density (BMD) in subjects who had never smoked. Pulmonary function was associated with BMD in premenopausal, but not postmenopausal, women. INTRODUCTION It has been reported that low bone mass is common in patients with pulmonary disorders such as chronic obstructive pulmonary disease. However, in healthy nonsmoking women, the relationship between bone mass and pulmonary function has yet to be clarified. The object of this study was to determine whether pulmonary function is related to BMD in healthy nonsmoking women based on menopausal status. METHODS This study was a cross-sectional study based on data obtained from the Korean National Health and Nutrition Examination Survey (KNHANES), a nationwide representative survey conducted by the Korean Ministry of Health and Welfare in 2010. This study included 456 subjects who had never smoked and analyzed data concerning pulmonary function and BMD. RESULTS Functional vital capacity (FVC) and forced expiratory volume in 1 s (FEV1) were correlated with BMD at lumbar spine, femur neck (FN), and total hip in premenopausal women (p = 0.030, p = 0.003, p = 0.019, respectively, for FVC; p = 0.015, p = 0.006, p = 0.059, respectively, for FEV1). However, FVC and FEV1 were only correlated with BMD at FN in postmenopausal women (p = 0.003 for FVC; p = 0.006 for FEV1). Body mass index (BMI), FVC, and FEV1 were significantly related with BMD at FN, even after adjusting for age and other confounding factors (β = 0.334, p < 0.001; β = 0.145, p = 0.017; and β = 0.129, p = 0.037, respectively) in premenopausal women. However, only age and BMI were correlated with BMD at FN (β = -0.268, p = 0.001 and β = 0.384, p > 0.001) in postmenopausal women after adjusting for confounding factors. CONCLUSIONS Pulmonary function, including FVC and FEV1 are associated with BMD at FN in healthy nonsmoking premenopausal women but not in postmenopausal women.
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Kim J, Yu S, Kim IJ, Lee S. 3D multi-spectrum sensor system with face recognition. SENSORS 2013; 13:12804-29. [PMID: 24072025 PMCID: PMC3859038 DOI: 10.3390/s131012804] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 08/20/2013] [Revised: 09/16/2013] [Accepted: 09/17/2013] [Indexed: 11/24/2022]
Abstract
This paper presents a novel three-dimensional (3D) multi-spectrum sensor system, which combines a 3D depth sensor and multiple optical sensors for different wavelengths. Various image sensors, such as visible, infrared (IR) and 3D sensors, have been introduced into the commercial market. Since each sensor has its own advantages under various environmental conditions, the performance of an application depends highly on selecting the correct sensor or combination of sensors. In this paper, a sensor system, which we will refer to as a 3D multi-spectrum sensor system, which comprises three types of sensors, visible, thermal-IR and time-of-flight (ToF), is proposed. Since the proposed system integrates information from each sensor into one calibrated framework, the optimal sensor combination for an application can be easily selected, taking into account all combinations of sensors information. To demonstrate the effectiveness of the proposed system, a face recognition system with light and pose variation is designed. With the proposed sensor system, the optimal sensor combination, which provides new effectively fused features for a face recognition system, is obtained.
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Kim IJ, Kim DH, Jung JY, Song YW, Guermazi A, Crema MD, Hunter DJ, Kim HA. Association between bone marrow lesions detected by magnetic resonance imaging and knee pain in community residents in Korea. Osteoarthritis Cartilage 2013; 21:1207-13. [PMID: 23973132 DOI: 10.1016/j.joca.2013.05.001] [Citation(s) in RCA: 23] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 11/20/2012] [Revised: 04/10/2013] [Accepted: 05/01/2013] [Indexed: 02/02/2023]
Abstract
OBJECTIVE To describe the frequency of bone marrow lesions (BMLs) detected by magnetic resonance imaging (MRI), and to examine the association of BMLs with knee pain severity in community residents in Korea. METHODS Participants were randomly chosen from the population-based Hallym Aging Study, irrespective of whether they had knee osteoarthritis (OA) or pain. Demographic and knee pain data were obtained by questionnaire. Radiographic evaluations consisted of weight-bearing knee anteroposterior radiographs and 1.5-T MRI scans. MRI was performed in the dominant knees of subjects without knee pain and in the more symptomatic knees of subjects with knee pain. BMLs were graded according to the whole-organ MRI score. RESULTS The mean age of the 358 study subjects was 71.8 years, and 34.5% of subjects had radiographically detected knee OA. The prevalences of BMLs and large BMLs in the tibiofemoral compartments were 80.3% and 40.4%, respectively. After adjusting for age, sex, and body mass index, total and medial compartment BML scores were significantly associated with the presence of knee pain, and the association was stronger as the summary score for BML increased. In proportional regression analysis, knee pain severity increased with BML severity in any compartment and in the medial compartment. CONCLUSION BMLs detected by MRI were highly prevalent in this elderly Asian population. BMLs were significantly linked to knee pain, and BML severity correlated with knee pain severity. BMLs may be important surrogate targets for monitoring pain and structure modification in OA therapeutics.
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Kosslyn SM, Thompson WL, Kim IJ, Rauch SL, Alpert NM. Individual differences in cerebral blood flow in area 17 predict the time to evaluate visualized letters. J Cogn Neurosci 2013; 8:78-82. [PMID: 23972237 DOI: 10.1162/jocn.1996.8.1.78] [Citation(s) in RCA: 58] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/04/2022]
Abstract
Sixteen subjects closed their eyes and visualized uppercase letters of the alphabet at two sizes, as small as possible or as large as possible while remaining "visible." Subjects evaluated a shape characteristic of each letter (e.g., whether it has any curved lines), and responded as quickly as possible. Cerebral blood flow was normalized to the same value for each subject, and relative blood flow was computed for a set of regions of interest. The mean response time for each subject in the task was regressed onto the blood flow values. Blood flow in area 17 was negatively correlated with response time (r = -0.65), as was blood flow in area 19 (r = -0.66), whereas blood flow in the inferior parietal lobe was positively correlated with response time (r = 0.54). The first two effects persisted even when variance due to the other correlations was removed. These findings suggest that individual differences in the activation of specific brain loci are directly related to performance of tasks that rely on processing in those loci.
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Margarone D, Klimo O, Kim IJ, Prokůpek J, Limpouch J, Jeong TM, Mocek T, Pšikal J, Kim HT, Proška J, Nam KH, Stolcová L, Choi IW, Lee SK, Sung JH, Yu TJ, Korn G. Laser-driven proton acceleration enhancement by nanostructured foils. PHYSICAL REVIEW LETTERS 2012; 109:234801. [PMID: 23368211 DOI: 10.1103/physrevlett.109.234801] [Citation(s) in RCA: 35] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/03/2012] [Indexed: 06/01/2023]
Abstract
Nanostructured thin plastic foils have been used to enhance the mechanism of laser-driven proton beam acceleration. In particular, the presence of a monolayer of polystyrene nanospheres on the target front side has drastically enhanced the absorption of the incident 100 TW laser beam, leading to a consequent increase in the maximum proton energy and beam charge. The cutoff energy increased by about 60% for the optimal spheres' diameter of 535 nm in comparison to the planar foil. The total number of protons with energies higher than 1 MeV was increased approximately 5 times. To our knowledge this is the first experimental demonstration of such advanced target geometry. Experimental results are interpreted and discussed by means of 2(1/2)-dimensional particle-in-cell simulations.
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Cha HJ, Choi IW, Kim HT, Kim IJ, Nam KH, Jeong TM, Lee J. Absolute energy calibration for relativistic electron beams with pointing instability from a laser-plasma accelerator. THE REVIEW OF SCIENTIFIC INSTRUMENTS 2012; 83:063301. [PMID: 22755616 DOI: 10.1063/1.4725530] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/01/2023]
Abstract
The pointing instability of energetic electron beams generated from a laser-driven accelerator can cause a serious error in measuring the electron spectrum with a magnetic spectrometer. In order to determine a correct electron spectrum, the pointing angle of an electron beam incident on the spectrometer should be exactly defined. Here, we present a method for absolutely calibrating the electron spectrum by monitoring the pointing angle using a scintillating screen installed in front of a permanent dipole magnet. The ambiguous electron energy due to the pointing instability is corrected by the numerical and analytical calculations based on the relativistic equation of electron motion. It is also possible to estimate the energy spread of the electron beam and determine the energy resolution of the spectrometer using the beam divergence angle that is simultaneously measured on the screen. The calibration method with direct measurement of the spatial profile of an incident electron beam has a simple experimental layout and presents the full range of spatial and spectral information of the electron beams with energies of multi-hundred MeV level, despite the limited energy resolution of the simple electron spectrometer.
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Pak K, Kim SJ, Kim IJ, Nam HY, Kim BS, Kim K, Kim YK. Clinical implication of (18)F-FDG PET/CT in carcinoma of unknown primary. Neoplasma 2011; 58:135-9. [PMID: 21275463 DOI: 10.4149/neo_2011_02_135] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/08/2022]
Abstract
The value of (18)F-Fluorodeoxyglucose positron emission tomography/computed tomography (FDG PET/CT) in the detection of carcinoma of unknown primary (CUP) differs among the studies. This study aimed to evaluate the role of (18)F-FDG PET/CT in CUP. Fifty-one patients (19 women, 32 men) with metastasis confirmed by histopathology from an unknown primary tumor were included in this study. Patients received 370 MBq of (18)F-FDG intravenously, and PET/CT was performed at 60 minutes after injection. Primary tumor sites were detected in 5 of 51 patients (9.6%): in 2 patients with carcinoma of the lung, in 1 patient with carcinoma of the gallbladder, in 1 patient with carcinoma of the esophagus, and in 1 patient with carcinoma of the stomach. No primary tumor was discovered in the remaining 46 patients (90.4%) during the follow-up. The sensitivity, specificity, and accuracy of (18)F-FDG PET/CT were 100%, 80.4%, and 82.4%. The positive and negative predictive values were 35.7 and 100%, respectively. Based on the data presented, (18)F-FDG PET/CT has a clinical implicative value in detecting the primary tumor of CUP. PET/CT can be useful to rule out the possibility of detecting the primary tumor during the follow-up.
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Kim YS, Kim SJ, Kim YK, Kim IJ, Kim YD, Lee MK. Prediction of survival and cancer recurrence using F-18 FDG PET/CT in patients with surgically resected early stage (Stage I and II) non-small cell lung cancer. Neoplasma 2011; 58:245-50. [PMID: 21391742 DOI: 10.4149/neo_2011_03_245] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/08/2022]
Abstract
The aim of the current study was to investigate the prognostic value of SUV(max) in patients with completely resected early stage (stage I and II) NSCLC. A retrospective review identified 76 patients with surgically resected early (stage I and II) NSCLC who received F-18 FDG PET/CT at diagnosis of cancer. Survival analysis was conducted using Kaplan-Meier analysis, and survival curves stratified by age, sex, mediastinal lymph node involvement, SUV(max), and TNM staging were generated for estimation of overall survival and disease free survival (DFS). Independent predictive factors for survival were determined using Cox proportional hazard model. For overall survival, the median survival of the patients with tumor SUV(max)≤ 6.7 was 48.9 months and was significantly longer than the patients with tumor SUV(max)>6.7 (Log rank test, Χ²=18.01, p5.9. The median survival of the patients with tumor SUV(max)≤ 5.9 was 31.7 months (Log rank test, Χ²=16, p=0.0001). In conclusion, high FDG uptake measured by F-18 FDG PET/CT might have a prognostic value for overall survival and DFS in surgically resected early stage (stage I and II) NSCLC even after stratified by pathologic stages.
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Kim BH, Kim IJ, Cho KI, Kim SM, Lee HG, Kim TI. The Influence of Diabetes on the Relationship between N-terminal Pro-B-type Natriuretic Peptide and Body Mass Index. J Int Med Res 2010; 38:1737-48. [PMID: 21309488 DOI: 10.1177/147323001003800519] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/17/2022] Open
Abstract
This study evaluated the influence of diabetes on the relationship between N-terminal pro-B-type natriuretic peptide (NT-proBNP) and body mass index (BMI). Simultaneous NT-proBNP and echocardiographic Doppler examinations were performed in 1117 patients with dyspnoea undergoing cardiac catheterization. Patients were divided into BMI ≥ 25 kg/m2 (obese), 23 − 25 kg/m2 (overweight) and < 23 kg/m2 (non-obese) groups. In the 803 non-diabetic patients, mean plasma NT-proBNP levels in non-obese, overweight and obese patients showed a significant negative correlation with BMI (862.3 ± 228.8 pg/ml, 611.5 ± 149.7 pg/ml, 278.3 ± 172.5 pg/ml, respectively). In the 314 patients with diabetes, there was no correlation between BMI and NT-proBNP. This study demonstrated that obese patients had reduced concentrations of NT-proBNP compared with non-obese patients, despite having higher left ventricular filling pressures. NT-proBNP was not reduced in obese patients with diabetes. These results suggest that factors other than cardiac status impact on NT-proBNP concentration.
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Kim YS, Lee MK, Kim SJ, Kim IJ, Kim YK, Jo WS, Park SK. Prognostic stratification using F-18 FDG PET/CT in patients with advanced stage (Stage III and IV) non-small cell lung cancer. Neoplasma 2010; 57:241-6. [PMID: 20353275 DOI: 10.4149/neo_2010_03_241] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/08/2022]
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Lee S, Park HK, Son SP, Lee CW, Kim IJ, Kim HJ. Effects of oral magnesium supplementation on insulin sensitivity and blood pressure in normo-magnesemic nondiabetic overweight Korean adults. Nutr Metab Cardiovasc Dis 2009; 19:781-788. [PMID: 19359148 DOI: 10.1016/j.numecd.2009.01.002] [Citation(s) in RCA: 37] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 07/16/2008] [Revised: 12/16/2008] [Accepted: 01/09/2009] [Indexed: 12/15/2022]
Abstract
BACKGROUND AND AIM Little is known about the effect of magnesium on insulin sensitivity and BP in healthy individuals. Therefore, we investigated whether magnesium could improve insulin sensitivity and blood pressure (BP) in normo-magnesemic nondiabetic overweight adults. METHODS AND RESULTS In a double-blinded, placebo-controlled, randomized trial, a total of 155 participants (BMI > or = 23 kg/m(2)) received either 12.3 mmol (300 mg) of elemental magnesium in the form of magnesium oxide (n=75) or placebo (n=80) each day for 12 weeks, constituting the intent-to-treat population. A repeated-measures ANOVA was used to evaluate the between-group changes in variables during the study. The baseline characteristics between the intervention and control groups were similar. There were no significant differences between the groups in the pattern of change of the homeostasis model assessment insulin resistance index, BP over time during the 12-week study. In subgroup analysis, magnesium supplementation (n=8, 27, and 24, respectively) lowered BP much more than placebo (n=16, 29, and 25, respectively) in those subjects whose systolic BP > or = 140 mmHg, diastolic BP 80-90 mmHg, and diastolic BP > or = 90 mmHg at the start of the study (P=0.016, 0.043, and 0.023, respectively); in comparison, those subjects whose initial BP reading was low at baseline did not show a change in BP. No significant adverse events related to magnesium supplementation were recorded. CONCLUSIONS These results suggested that magnesium supplementation does not reduce BP and enhance insulin sensitivity in normo-magnesemic nondiabetic overweight people. However, it appears that magnesium supplementation may lower BP in healthy adults with higher BP.
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Kim G, Kim H, Kim IJ, Kim JR, Lee JI, Ree M. Bacterial adhesion, cell adhesion and biocompatibility of Nafion films. JOURNAL OF BIOMATERIALS SCIENCE-POLYMER EDITION 2009; 20:1687-707. [PMID: 19723436 DOI: 10.1163/156856208x386273] [Citation(s) in RCA: 33] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/19/2022]
Abstract
We investigated bioadhesion (bacterial and cell adhesion) and biocompatibility of poly(tetrafluoroethylene-co-perfluoro-3,6-dioxa-4-methyl-7-octenesulfonic acid) (Nafion) and compared the results with those obtained with poly(vinylidene fluoride-co-hexafluoropropylene) (PVFHFP). When incubated with bacteria for 4 h to 7 days, Nafion film exhibited scarce bacterial adhesion at 6 h, after which the adhesion gradually increasing to relatively low levels. In contrast, significant bacterial adhesion to PVFHFP film was observed at 4 h, and much higher adhesion levels were shown thereafter. Although HEp-2 human cells adhered normally to both films, reaching confluence in 7-8 days, the cells adhered to Nafion appeared more lively and stable than those to PVFHFP. Subcutaneous implantation in mice revealed that Nafion elicited a mild acute inflammatory reaction without chronic inflammation or tissue necrosis, indicating excellent biocompatibility in mice. PVFHFP, however, provoked a moderate and prolonged acute inflammatory response. These differences in the biological characteristics of Nafion and PVFHFP films may be attributable to the differences in the chemical and physical natures of these polymer films. Nafion film provided a sufficiently solid support, expressing a high surface charge density and good water-wettability. In summary, Nafion is suitable for use in biomedical applications that require biocompatibility with a reduced possibility of post-operative infections.
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Choi IW, Kim CM, Sung JH, Yu TJ, Lee SK, Kim IJ, Jin YY, Jeong TM, Hafz N, Pae KH, Noh YC, Ko DK, Yogo A, Pirozhkov AS, Ogura K, Orimo S, Sagisaka A, Nishiuchi M, Daito I, Oishi Y, Iwashita Y, Nakamura S, Nemoto K, Noda A, Daido H, Lee J. Ion spectrometer composed of time-of-flight and Thomson parabola spectrometers for simultaneous characterization of laser-driven ions. THE REVIEW OF SCIENTIFIC INSTRUMENTS 2009; 80:053302. [PMID: 19485501 DOI: 10.1063/1.3131628] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/27/2023]
Abstract
An ion spectrometer, composed of a time-of-flight spectrometer (TOFS) and a Thomson parabola spectrometer (TPS), has been developed to measure energy spectra and to analyze species of laser-driven ions. Two spectrometers can be operated simultaneously, thereby facilitate to compare the independently measured data and to combine advantages of each spectrometer. Real-time and shot-to-shot characterizations have been possible with the TOFS, and species of ions can be analyzed with the TPS. The two spectrometers show very good agreement of maximum proton energy even for a single laser shot. The composite ion spectrometer can provide two complementary spectra measured by TOFS with a large solid angle and TPS with a small one for the same ion source, which are useful to estimate precise total ion number and to investigate fine structure of energy spectrum at high energy depending on the detection position and solid angle. Advantage and comparison to other online measurement system, such as the TPS equipped with microchannel plate, are discussed in terms of overlay of ion species, high-repetition rate operation, detection solid angle, and detector characteristics of imaging plate.
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Kim HA, Koh SH, Lee B, Kim IJ, Seo YI, Song YW, Hunter DJ, Zhang Y. Low rate of total hip replacement as reflected by a low prevalence of hip osteoarthritis in South Korea. Osteoarthritis Cartilage 2008; 16:1572-5. [PMID: 18558502 PMCID: PMC4373077 DOI: 10.1016/j.joca.2008.04.024] [Citation(s) in RCA: 21] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 01/30/2008] [Accepted: 04/27/2008] [Indexed: 02/02/2023]
Abstract
OBJECTIVE We attempted to estimate the rate of total hip replacement (THR) using a national database and the prevalence of hip osteoarthritis (OA) from the reading of intravenous pyelograms (IVPs) in a Korean population. MATERIALS Reimbursement records from all hospitals in South Korea were extracted from the Health Insurance Review Agency (HIRA) database. Records with both the procedure code corresponding to THR and containing the diagnosis code for hip OA were selected. We estimated the age- and sex-specific rates of THR from 2002 to 2006. Hip joints from 580 subjects older than 70 years old who underwent an IVP were assessed for the presence of OA. RESULTS The rate of THR increased with age, reaching a peak over the age of 65-69 years, with the age-standardized risk ratios in women vs men of approximately 1.5. Although the rate of THR increased over the 5-year study period, it was significantly lower than that of total knee replacement (TKR) in Korean population (THR vs TKR 1:15.9). The prevalence of hip OA in the IVP cohort was 1.2% (1.7% for men and 0.7% for women). CONCLUSION The rate of THR was significantly lower than that of TKR in Korean population. Hip OA prevalence among the IVP subjects was 1.2%. Further studies on factors that account for the low prevalence of hip OA among Asians need to be conducted.
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Kim IJ, Kim SJ, Kim YK. Comparison of double phase Tc-99m MIBI and Tc-99m tetrofosmin scintimammography for characterization of breast lesions: Visual and quantitative analyses. Neoplasma 2008; 55:526-531. [PMID: 18999882] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 05/27/2023]
Abstract
The aim of the current study was to compare the diagnostic reliability of visual and quantitative indices of double phase Tc-99m MIBI scintimammography (M-SMM) and Tc-99m Tetrofosmin scintimammography (TF-SMM) for detection of breast cancer. Double phase M-SMM and TF-SMM (early; 10 minutes, delayed; hour) were performed after injection of 925 MBq of radiotracers in 75 highly suspected breast cancer patients (malignant:49, benign:26). For visual analysis, five scoring methods were used. For quantitative analysis, early, delayed lesions to non-lesion ratios (L/Ns), and washout rate (%, WR) were calculated. When over grade of visual grade was used as cut-off value in the detection of primary breast cancer, M-SMM and TF-SMM showed similar diagnostic accuracies. The optimal quantitative indices of M-SMM for the detection of breast cancer were 2.06 for early L/N and 1.72 for delayed L/N. Those of TF-SMM were 3.13 for early, and 2.56 for delayed image. Visual and quantitative analyses showed similar results. However, delayed L/N of M-SMM was superior to that of TF-SMM for the detection of breast cancer. In conclusion, the double phase M-SMM and TF-SMM showed favorable diagnostic accuracy in differentiating benign from malignant breast lesions, visually and quantitatively. The optimal visual interpretation grades for the detection of primary breast cancer of double phase M-SMM and TF-SMM were grade and 5. The optimal quantitative indices of M-SMM for the detection of breast cancer were 2.06 for early L/N and 1.72 for delayed L/N. Those of TF-SMM were 3.13 for early, and 2.56 for delayed image.
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Rodriguez-Osorio N, Kim IJ, Wang H, Kaya A, Memili E. Melatonin increases cleavage rate of porcine preimplantation embryos in vitro. J Pineal Res 2007; 43:283-8. [PMID: 17803526 DOI: 10.1111/j.1600-079x.2007.00475.x] [Citation(s) in RCA: 97] [Impact Index Per Article: 5.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
Melatonin has been used to promote in vitro embryo development in different species. This study determined the effects of melatonin on in vitro porcine embryo development; in particular, cleavage rate, blastocyst rate, and blastocyst cell number. Starting 5 hr after insemination, porcine zygotes were cultured in porcine zygote medium 3 (PZM-3) culture medium supplemented with melatonin at increasing concentrations (10(-12) M, 10(-9) M, 10(-6) M, 10(-3) M). Melatonin at a concentration of 10(-9) M had a positive effect on cleavage rates, while the highest concentration of melatonin (10(-3) M) significantly decreased cleavage rates. Although blastocyst rates were not increased by 10(-9) M melatonin, blastocyst cell numbers were significantly higher for embryos subjected to 10(-9) M melatonin. The expression levels of the pro-apoptotic gene BAX and anti-apoptotic gene BCL2L1 in blastocysts were not affected by the presence of melatonin in the culture medium. To further study the protective properties of 10(-9) M melatonin against stressful conditions, hydrogen peroxide (0.01 mm) and heat (40 degrees C) were used during embryo culture. The addition of melatonin to embryos subjected to 40 degrees C for 3 hr increased cleavage rates, but had no protective effect for embryos subjected to 0.01 mm H(2)O(2), probably because the physiological levels of melatonin could not counteract the pharmacological levels of H(2)O(2). Our data indicate that 10(-9) M melatonin has a positive effect on porcine embryo cleavage rates and blastocyst total cell numbers and it might have a protective effect against heat stress.
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