3D 광학 스캐너를 이용한 인체모형 팬텀 표면 데이터 획득 및 X-ray 에너지의 몬테카를로 시뮬레이션(MCs)을 이용한 팬텀 선량 평가와 영상구현

신준봉(Jun-Bong Shin),이도희(Do-Heui Lee),윤경준(Kyoung-Jun Yoon),박민재(Min-Jae Park),고영문(Young-Moon Go),김성우(Sung-Woo Kim),홍승모(Seung-Mo Hong),이현철(Hyun-Cheol Lee),이의섭(Ui-Seob Lee),노선영(Seon-Yeong No),강석윤(Seok-Yoon 대한영상의학기술학회 2021 대한영상의학기술학회 논문지 Vol.2021 No.-

목 적:본 연구의 목적은 기존 컴퓨터단층촬영(Computed tomography, 이하 CT) 스캔 방법 대신 3D 광학 스캐너 (3D optical scanner)를 이용하여 인체모형 팬텀의 표면 데이터를 획득하고 기존 CT 스캔 표면 데이터와 3D 광학 스캔 표면 데이터 차이를 비교 분석하는 것이며, 3D 광학 스캔 표면 데이터를 몬테카를로 시뮬레이션(Monte Carlo Simulation, MCs)에 적용하여 일반 촬영 에너지조건으로 팬텀 선량 평가와 영상 구현을 연구하는 것입니다. 연구방법: 일반촬영의 선량 평가를 위해 환자 표면 데이터를 얻을 때 3D 광학 스캐너를 활용할 것을 제안합니다. 우리는 3D 광학 스캐너(Go!SCAN SPARKTM, CREAFORM) 사용하여 기존 CT 스캔 방법을 대신해 인체모형 팬텀의 표면 데이터를 얻었습니다. 3D 스캔 표면 데이터를 정렬하고 편집하기 위해 Meshlab 프로그램을 이용하였으며, 3D slicer 프로그램을 이용하여 CT 스캔 표면 데이터와 3D 스캔 표면 데이터 차이를 정량적으로 비교분석 하였습니다. 또한 3D 스캔 표면 데이터 분석 프로그램(VXelements, CREAFORM)을 사용하여 인체 모형 팬텀의 재현성을 평가 하였습니다. SpekCalc 프로그램을 이용하여 X-ray beam 에너지 스펙트럼을 계산하고 Geant4 기반의 MCs인 TOPAS를 이용하여 X-ray Beam을 모델링 하였습니다. 인체모형 팬텀을 MCs에 적용 하여 일반촬영 에너지 조건으로 팬텀 선량을 평가하고 Phase space data 통해 영상을 구현을 연구 하였습니다. 결 과:3D slicer를 이용한 CT 스캔 표면 데이터와 3D 광학 스캔 표면 데이터의 정량적 비교 분석에서 Hounsdroff distance는 Average 2.45 mm, Dice coefficient는 0.97로 나타나 CT 스캔 표면 데이터와 3D 스캔 표면 데이터가 거의 일치하는 것을 확인할 수 있었습니다. 또한 인체모형 팬텀 재현성 평가에서 인체모형 팬텀의 AP position, RAO position, LAO position 기준으로 팔이 있는 팬텀의 error distribution은 2 mm 오차 범위에서 평균 89.78%가, 4 mm 오차 범위에서 96.05%가 일치하는 것으로 나타났으며, 팔을 제외한 경우 error distribution은 2 mm 오차 범위에서 평균 96.48%가, 4 mm 오차 범위에서 99.45%가 일치하는 것으로 나타나 3D 광학 스캐너의 표면 데이터 재현성이 우수한 것으로 나타났습니다. 인체모형 팬텀을 이용한 3D 스캔 표면 데이터를 MCs에 적용하여 전신일반촬영 에너지 조건으로 팬텀선량 평가가 가능하며, Phase space data 통해 영상을 구현할 수 있다는 것을 확인 하였습니다. 결 론:본 연구에서 3D 광학 스캐너를 사용한 인체모형 팬텀 데이터 획득은 기존 CT scan 방식보다 간편하고 방사선 노출 없이 다양한 위치와 균일한 표면 구조의 정보를 정밀하게 얻을 수 있으며 MCs을 이용한 선량계산이 가능하며, Phase space data 통해 영상을 구현이 가능함에 따라 앞으로 일반촬영 분야의 활용과 선량평가에 매우 유용할 것으로 생각 됩니다. Purpose:The purpose of this work is to acquire surface data of anthropromophic phantom using 3D optical scanner instead of conventional computed tomography (CT) scanning methods and to compare the differences between existing CT scan surface data and 3D optical scan surface data. also it is to apply 3D optical scan surface data to Monte Carlo simulations (MCs) to study whether phantom dose evaluation and image implementation are possible under general shooting energy conditions. Targets and Methods:We suggest utilizing a 3D optical scanner when obtaining patient surface data for dose evaluation of normal photography. We obtained surface data of anthropromophic phantom instead of conventional CT scanning methods using 3D optical scanners (Go!SCAN SPARKTM, CREAFORM). The Meshlab program was used to sort and edit 3D scan surface data, and the CT scan surface data and 3D scan surface data differences were quantitatively compared using the 3D slicer program. The reproducibility of the dummy phantom was also evaluated using the 3D Scan Surface Data Analysis Program (VXelements, CREAFORM). Using the SpekCalc program, the X-ray beam energy spectrum was calculated and the X-ray beam was modeled using TOPAS, a Geant4-based MCs. We applied the anthropromophic phantom to MCs evaluate the phantom dose in X-ray energy conditions and study whether the image can be implemented through phase space data. Result:Quantitative comparative analysis of CT scan surface data and 3D optical scan surface data using 3D slicer showed that Hounsdroff distance was Average 2.45 mm and Dice coefficient was 0.97, indicating a close match between CT scan surface data and 3D scan surface data. In addition, the anthropromophic phantom reproducibility assessment shows that the error distribution of the phantom with arms by AP position, RAO position, and LAO position of the anthropromophic phantom averaged 89.78% in the 2 mm error range and 96.05% in the 4 mm error range. MCs using anthropromophic phantom confirmed that 3D scan surface data can be applied to Monte Carlo simulation to evaluate phantom dose under X-ray energy conditions through phase space data. Conclusion:In this study, anthropromophic phan tom data acquisition using 3D optical scanners is simpler than conventional CT scan methods, provides precise information of various locations and uniform surface structures without radiation exposure, enables dosing using MCs, and enables image implementation through phase space data.

Functional Screening of a Metagenomic Library Reveals Operons Responsible for Enhanced Intestinal Colonization by Gut Commensal Microbes

Yoon, Mi Young,Lee, Kang-Mu,Yoon, Yujin,Go, Junhyeok,Park, Yongjin,Cho, Yong-Joon,Tannock, Gerald W.,Yoon, Sang Sun American Society for Microbiology 2013 Applied and environmental microbiology Vol.79 No.12

<P>Evidence suggests that gut microbes colonize the mammalian intestine through propagation as an adhesive microbial community. A bacterial artificial chromosome (BAC) library of murine bowel microbiota DNA in the surrogate host <I>Escherichia coli</I> DH10B was screened for enhanced adherence capability. Two out of 5,472 DH10B clones, 10G6 and 25G1, exhibited enhanced capabilities to adhere to inanimate surfaces in functional screens. DNA segments inserted into the 10G6 and 25G1 clones were 52 and 41 kb and included 47 and 41 protein-coding open reading frames (ORFs), respectively. DNA sequence alignments, tetranucleotide frequency, and codon usage analysis strongly suggest that these two DNA fragments are derived from species belonging to the genus <I>Bacteroides</I>. Consistent with this finding, a large portion of the predicted gene products were highly homologous to those of <I>Bacteroides</I> spp. Transposon mutagenesis and subsequent experiments that involved heterologous expression identified two operons associated with enhanced adherence. <I>E. coli</I> strains transformed with the 10a or 25b operon adhered to the surface of intestinal epithelium and colonized the mouse intestine more vigorously than did the control strain. This study has revealed the genetic determinants of unknown commensals (probably resembling <I>Bacteroides</I> species) that enhance the ability of the bacteria to colonize the murine bowel.</P>

Thermal transfer behavior in two types of W-shape ground heat exchangers installed in multilayer soils

Yoon, Seok,Lee, Seung-Rae,Go, Gyu-Hyun,Xue, Jianfeng,Park, Hyunku,Park, Dowon Techno-Press 2014 Geomechanics & engineering Vol.6 No.1

This paper presents an experimental and numerical study on the evaluation of a thermal response test using a precast high-strength concrete (PHC) energy pile and a closed vertical system with W-type ground heat exchangers (GHEs). Field thermal response tests (TRTs) were conducted on a PHC energy pile and on a general vertical GHE installed in a multiple layered soil ground. The equivalent ground thermal conductivity was determined by using the results from TRTs. A simple analytical solution is suggested in this research to derive an equivalent ground thermal conductivity of the multilayered soils for vertically buried GHEs. The PHC energy pile and general vertical system were numerically modeled using a three dimensional finite element method to compare the results with TRTs'. Borehole thermal resistance values were also obtained from the numerical results, and they were compared with various analytical solutions. Additionally, the effect of ground thermal conductivity on the borehole thermal resistance was analyzed.

A new thermal conductivity estimation model for weathered granite soils in Korea

Go, Gyu-Hyun,Lee, Seung-Rae,Kim, Young-Sang,Park, Hyun-Ku,Yoon, Seok Techno-Press 2014 Geomechanics & engineering Vol.6 No.4

Thermal conductivity of ground has a great influence on the performance of Ground Heat Exchangers (GHEs). In general, the ground thermal conductivity significantly depends on the density (or porosity) and the moisture content since they are decisive factors that determine the interface area between soil particles which is available for heat transfer. In this study, a large number of thermal conductivity experiments were conducted for soils of varying porosity and moisture content, and a database of thermal properties for the weathered granite soils was set up. Based on the database, a 3D Curved Surface Model and an Artificial Neural Network Model (ANNM) were proposed for estimating the thermal conductivity. The new models were validated by comparing predictions by the models with new thermal conductivity data, which had not been used in developing the models. As for the 3D CSM, the normalized average values of training and test data were 1.079 and 1.061 with variations of 0.158 and 0.148, respectively. The predictions became somewhat unreliable in a low range of thermal conductivity values in considering the distribution pattern. As for the ANNM, the 'Logsig-Tansig' transfer function combination with nine neurons gave the most accurate estimates. The normalized average values of training data and test data were 1.006 and 0.954 with variations of 0.026 and 0.098, respectively. It can be concluded that the ANNM gives much better results than the 3D CSM.

Microarray Analysis of Gene Expression Alteration in Human Middle Ear Epithelial Cells Induced by Asian Sand Dust

Go, Yoon Young,Park, Moo Kyun,Kwon, Jee Young,Seo, Young Rok,Chae, Sung-Won,Song, Jae-Jun Korean Society of Otorhinolaryngology-Head and Nec 2015 Clinical and Experimental Otorhinolaryngology Vol.8 No.4

<P><B>Objectives</B></P><P>The primary aim of this study is to evaluate the gene expression profile of Asian sand dust (ASD)-treated human middle ear epithelial cell (HMEEC) using microarray analysis.</P><P><B>Methods</B></P><P>The HMEEC was treated with ASD (400 µg/mL) and total RNA was extracted for microarray analysis. Molecular pathways among differentially expressed genes were further analyzed. For selected genes, the changes in gene expression were confirmed by real-time polymerase chain reaction.</P><P><B>Results</B></P><P>A total of 1,274 genes were differentially expressed by ASD. Among them, 1,138 genes were 2 folds up-regulated, whereas 136 genes were 2 folds down-regulated. Up-regulated genes were mainly involved in cellular processes, including apoptosis, cell differentiation, and cell proliferation. Down-regulated genes affected cellular processes, including apoptosis, cell cycle, cell differentiation, and cell proliferation. The 10 genes including <I>ADM</I>, <I>CCL5</I>, <I>EDN1</I>, <I>EGR1</I>, <I>FOS</I>, <I>GHRL</I>, <I>JUN</I>, <I>SOCS3</I>, <I>TNF</I>, and <I>TNFSF10</I> were identified as main modulators in up-regulated genes. A total of 11 genes including <I>CSF3</I>, <I>DKK1</I>, <I>FOSL1</I>, <I>FST</I>, <I>TERT</I>, <I>MMP13</I>, <I>PTHLH</I>, <I>SPRY2</I>, <I>TGFBR2</I>, <I>THBS1</I>, and <I>TIMP1</I> acted as main components of pathway associated with 2-fold down regulated genes.</P><P><B>Conclusion</B></P><P>We identified the differentially expressed genes in ASD-treated HMEEC. Our work indicates that air pollutant like ASD, may play an important role in the pathogenesis of otitis media.</P>

Inhibition of Pyruvate Dehydrogenase Kinase 2 Protects Against Hepatic Steatosis Through Modulation of Tricarboxylic Acid Cycle Anaplerosis and Ketogenesis

Go, Younghoon,Jeong, Ji Yun,Jeoung, Nam Ho,Jeon, Jae-Han,Park, Bo-Yoon,Kang, Hyeon-Ji,Ha, Chae-Myeong,Choi, Young-Keun,Lee, Sun Joo,Ham, Hye Jin,Kim, Byung-Gyu,Park, Keun-Gyu,Park, So Young,Lee, Chul- American Diabetes Association 2016 Diabetes Vol.65 No.10

<P>Hepatic steatosis is associated with increased insulin resistance and tricarboxylic acid (TCA) cycle flux, but decreased ketogenesis and pyruvate dehydrogenase complex (PDC) flux. This study examined whether hepatic PDC activation by inhibition of pyruvate dehydrogenase kinase 2 (PDK2) ameliorates these metabolic abnormalities. Wildtype mice fed a high-fat diet exhibited hepatic steatosis, insulin resistance, and increased levels of pyruvate, TCA cycle intermediates, and malonyl-CoA but reduced ketogenesis and PDC activity due to PDK2 induction. Hepatic PDC activation by PDK2 inhibition attenuated hepatic steatosis, improved hepatic insulin sensitivity, reduced hepatic glucose production, increased capacity for beta-oxidation and ketogenesis, and decreased the capacity for lipogenesis. These results were attributed to altered enzymatic capacities and a reduction in TCA anaplerosis that limited the availability of oxaloacetate for the TCA cycle, which promoted ketogenesis. The current study reports that increasing hepatic PDC activity by inhibition of PDK2 ameliorates hepatic steatosis and insulin sensitivity by regulating TCA cycle anaplerosis and ketogenesis. The findings suggest PDK2 is a potential therapeutic target for nonalcoholic fatty liver disease.</P>

Pellino 1 promotes lymphomagenesis by deregulating BCL6 polyubiquitination.

Park, Hye-Young,Go, Heounjeong,Song, Ha Rim,Kim, Suhyeon,Ha, Geun-Hyoung,Jeon, Yoon-Kyung,Kim, Ji-Eun,Lee, Ho,Cho, Hyeseong,Kang, Ho Chul,Chung, Hee-Young,Kim, Chul-Woo,Chung, Doo Hyun,Lee, Chang-Woo American Society for Clinical Investigation 2014 The Journal of clinical investigation Vol.124 No.11

<P>The signal-responsive E3 ubiquitin ligase pellino 1 (PELI1) regulates TLR and T cell receptor (TCR) signaling and contributes to the maintenance of autoimmunity; however, little is known about the consequence of mutations that result in upregulation of PELI1. Here, we developed transgenic mice that constitutively express human PELI1 and determined that these mice have a shorter lifespan due to tumor formation. Constitutive expression of PELI1 resulted in ligand-independent hyperactivation of B cells and facilitated the development of a wide range of lymphoid tumors, with prominent B cell infiltration observed across multiple organs. PELI1 directly interacted with the oncoprotein B cell chronic lymphocytic leukemia (BCL6) and induced lysine 63-mediated BCL6 polyubiquitination. In samples from patients with diffuse large B cell lymphomas (DLBCLs), PELI1 expression levels positively correlated with BCL6 expression, and PELI1 overexpression was closely associated with poor prognosis in DLBCLs. Together, these results suggest that increased PELI1 expression and subsequent induction of BCL6 promotes lymphomagenesis and that this pathway may be a potential target for therapeutic strategies to treat B cell lymphomas.</P>

Hydrothermal Synthesis and Characteristics of LiMN₂O4 as Cathode Materials

Park, Ji-In,Hwang, Wan Sik,Park, Su Bin,Yoon, Sung Been,Kim, Gang Hyeon,Jo, Yong Joo,Kim, Hee Seok,Kim, Junki,Choi, Jeong Gon,Kim, Jong-Pil American Scientific Publishers 2018 Nanoscience and Nanotechnology Letters Vol.10 No.5

A Fully Closed Nano-Focus X-Ray Source With Carbon Nanotube Field Emitters

Park, Sora,Kang, Jun-Tae,Jeong, Jin-Woo,Kim, Jae-Woo,Yun, Ki Nam,Jeon, Hyojin,Go, Eunsol,Lee, Jeong-Woong,Ahn, Yujung,Yeon, Ji-Hwan,Kim, Sunghee,Song, Yoon-Ho IEEE 2018 IEEE electron device letters Vol.39 No.12

<P>We developed a fully closed nano-focus X-ray source using carbon nanotube (CNT) field emitters. The nano-focus X-ray source includes a fully vacuum-sealed CNT Electron-gun (E-gun) tube and E-beam-focusing modules consisting of electrostatic and magnetic lenses, facilitating very compact and high-resolution X-ray imaging. The paste-printed CNT emitters were prepared in a small pattern as an electron source, and the entire components, including the CNT emitter module, Cu tubes, collimators, and transmissive anode target, were specially brazed at an elevated temperature, resulting in a very compact E-gun tube. The CNT emitter showed a stable and reliable emission current with its density of over 300 mA/cm<SUP>2</SUP> even in the vacuum-sealed E-gun tube. With the anode grounded and the CNT emitter module biased to negative high voltages, we achieved a considerably magnified x-ray image of a several hundred nanometer resolution. The fully vacuum-sealed CNT E-gun tube along with the magnetic lens module can offer much more compact, easily maintainable, high-resolution X-ray imaging compared with conventional open-type thermionic X-ray sources.</P>

Study on the development of automatic translation service system for Korean astronomical classics by artificial intelligence - Focused on development results and test operation

Yoon Kyung Seo,Sang Hyuk Kim,Young Sook Ahn,Go-Eun Choi,Young Sil Choi,Hangi Baik,Bo Min Sun,Hyun Jin Kim,Byung Sook Choi,Sahng Woon Lee,Raejin Park 한국천문학회 2020 天文學會報 Vol.45 No.1