Effects of Light Intensity in Engineered Synechocystis sp. PCC 6803 for Phycobiliproteins Production

Seonghoon YOON,Mi-Jin KANG,Danbee YOO,Seong-Joo HONG,Choul-Gyun LEE 한국생물공학회 2020 한국생물공학회 학술대회 Vol.2020 No.10

Enhancement of Phycobiliproteins Production in Engineered Synechocystis sp. PCC 6803 by Box-behnken Design with Stress of Glutamate, NaCl and Light Intensity

Seonghoon YOON,Mi-Jin KANG,Hanbin RYU,Seong-Joo HONG,Choul-Gyun LEE 한국생물공학회 2021 한국생물공학회 학술대회 Vol.2021 No.4

탈의실의 중간기 최적 온열환경 조건에 관한 연구

윤성훈(SeongHoon Yoon) 인문사회과학기술융합학회 2018 예술인문사회융합멀티미디어논문지 Vol.8 No.5

목욕탕 탈의실의 온열환경 및 개선방안과 관련한 선행연구에서, 겨울철에 목욕 전과 후의 이용자에게 쾌적한 온열환경을 제공하기 위한 바닥난방 시의 표면온도와 실내 기류속도 조건에 대하여 검토한 바 있다. 본 연구에서는 봄, 가을과 같은 중간기에 대중목욕탕 탈의실의 온열환경에 대한 현황 및 목욕 전후 이용자의 대사량, 그리고 온열쾌적성을 확보하기 위한 최적 환경조절 조건에 대하여 검토를 실시하였다. 현장측정 및 설문조사 결과, 목욕 전과 후의 이용자가 느끼는 온열감은 각각 0.47, 0.20에 해당하는 PMV로 나타났으며, 착의량(CLO)이 없는 상태에서 피험자의 온열감에 해당하는 대사량(MET)을 역산한 결과, 목욕 전에는 1.8[met], 목욕 후에는 1.6[met]로 산출되었다. 또한 시뮬레이션을 통해 목욕 전후의 이용자에게 쾌적한 온열환경을 제공 가능한 천장면 표면온도 및 실내 기류속도에 대하여 분석을 실시하였다. 그 결과, 최적 기류속도 조건은 0.29m/s로 확인된 반면, 천장 표면온도는 15.2~20.7℃의 다소 넓은 범위에서 만족시키는 것으로 나타났다. In this study, the thermal environment in the changing room in intermediate season, and the optimum condition for providing the comfortable thermal environment to the users before and after the bath were examined. As a result of the field measurements and questionnaire survey, the thermal sensation of the users before and after the bath was 0.47 and 0.20, respectively. And the metabolic rate(MET) was calculated as 1.8[met] before bath and 1.6[met] after bath corresponding to the subject s thermal sensation while CLO was zero. In addition, the simulations were conducted to analyze the ceiling surface temperature and indoor airflow velocity to provide a comfortable thermal environment for the user before and after the bath. As a result, the optimal airflow velocity condition was confirmed to be 0.29[m/s] while the ceiling surface temperature was satisfied in wider range of 15.2 ~ 20.7[℃].

Relation of respiratory short chain fatty acids on bronchial inflammation in Asthma

Seonghoon Na,Minkyung Park,Sang-Heon Kim,Hye-Ran Yoon 한국분석과학회 2020 학술대회논문집 Vol.2020 No.11

Increased Eciency of Range Verification in Routine QA for Pencil-Beam Scanning Proton Therapy

Seonghoon Jeong,Myonggeun Yoon,Jaeman Son,Kwangzoo Chung 한국물리학회 2018 THE JOURNAL OF THE KOREAN PHYSICAL SOCIETY Vol.73 No.7

Quality assurance (QA) is required when performing pencil-beam scanning proton therapy, but the eciency of QA is degraded in proportion to the energy of the protons. We developed a method to assess the preferred energy range and distal fall-off by combining multiple Bragg peaks to increase the eciency of QA. Beams of 70, 110, 150, 190, and 230 MeV for exposure were planned using a treatment planning system. The Bragg curves for therapeutic proton beams were modeled using three different fitting function models, allowing the feasibility of a simple modeling of the Bragg curve to be investigated. The planned beams were exposed and measured using a multi-layered ionization chamber. Software developed using a Python tool could detect five Bragg peaks from the integrated curves that were fitted based on polynomial, cubic spline and Landau distributions. This software could calculate the range and distal fall-off of the five fitted peaks. For the verification of the accuracy of this method, the calculated results were compared with the range and distal fall- off obtained by exposing and analyzing five single-energy beams individually. Comparisons of the Bragg peaks for the five energies exposed individually with the results obtained by exposing them all at once showed that the ranges of the energy beams when using the polynomial fitting and the cubic spline modes were 0.16 mm and 0.10 mm longer, respectively, while the distal fall-offs were 0.14 mm and 0.06 mm shorter, respectively. When using the Landau distribution fitting, the range was 0.06 mm longer and the distal fall-off was 0.04 mm shorter. Analyses of the ranges and distal fall-offs of the five energy beams exposed at once with single-beam loading by using the method developed in this study showed no significant differences from the results obtained by exposing the energy beams individually. Thus, range verification QA by using the proposed method is not only suitable for single-proton beams with multiple energies but also reduces the measurement time.

Stereoselective method development for thyroxine(T4) enantiomers on chiral crown ether column using UPLC-ESI-MS/MS

Seonghoon Na,Suraj Adhikari,Hye-Ran Yoon,Wonjae Lee 한국분석과학회 2020 학술대회논문집 Vol.2020 No.11

Development of a Daily-Treatment Beam-Monitoring System Based on Gafchromic EBT3 Film for Pencil-Beam Scanning Proton Therapy

Seonghoon Jeong,Myonggeun Yoon,Kwangzoo Chung 한국물리학회 2020 THE JOURNAL OF THE KOREAN PHYSICAL SOCIETY Vol.76 No.8

This study describes the development of a simple method to assess inter-fractional deviations of delivered proton beams in treatment rooms. To monitor the treatment beam, we measured the field-by-field beam fluences by attaching the EBT3 film to the snout, followed by a simple constancy check based on comparisons between the reference beam fluences (acquired during the pre-treatment quality assurance process) and the test beam fluences (acquired during treatment). The feasibility of the proposed treatment beam-monitoring system was confirmed by evaluating 12 treatment fields for each of six patients (brain, liver, prostate, lung, cranial and spinal area, and head and neck). The constancy of the treatment beams was verified by using a gamma index analysis to compare three measurements per field with the reference beam fluence. On the basis of the 3%/3 mm criterion, the average gamma-index passing rates for all measurements were over 99.6%. These results suggest that the constancy of fractional proton beams delivered to patients in treatment rooms can be verified with EBT3 film-based proton-beam monitoring system that can be easily attached to the treatment nozzle and is cost effective.

초고성능액체크로마토그래피-텐덤질량분석법에 의한 혈청 중스핑고신과 스핑고신-1-포스페이트의 동시 분석

나승훈(Seonghoon Na),윤혜란(Hye-Ran Yoon) 대한약학회 2021 약학회지 Vol.65 No.1

Sphingosine (SPH) and sphingosine-1-phosphate (S1P) are emerging as key players in asthma metabolism and in numerous cellular inflammation processes. To identify potential biomarkers of asthma and inflammatory therapeutics, it is essential to determine their levels. Herein, we developed a rapid and sensitive UHPLC-MS/MS method to simultaneously quantify SPH and S1P in human serum using C17-SPH and C17-S1P as internal standards. After methanol precipitation of serum proteins, the supernatants were analyzed by MS/MS performed in the positive ion mode by multiple reaction monitoring. UHPLC analysis (C18 column) was performed using two mobile phase systems (water containing 0.1% formic acid, and 85% acetonitrile containing 0.1% formic acid) within 5 min of the short run. The calibration curves were linear in the range of 0.002-1.5 µg/mL for S1P and SPH with an R 2 greater than 0.9999. The LOD and LOQ were 0.0002 and 0.0004 µg/mL for S1P, and 0.0005 and 0.001 µg/mL for SPH, respectively. The accuracy and precision of the method were in the range of 89.8-100.7% (RSD, 1.5-2.8%) for both SPH and S1P species. We were able to quantify both molecules in serum from healthy and asthmatic patients. These results suggest that SPH and S1P are promising potential biomarkers, and also contribute to the basic data for the construction of an omics-based platform for preventive index prior to asthma diagnosis.

초고성능액체크로마토그래피-탠덤매스에 의한 혈장과 담즙 중 콜릭산의 정량 분석에 관한 연구

나승훈(Seonghoon Na),윤혜란(Hye-Ran Yoon) 대한약학회 2019 약학회지 Vol.63 No.6

Bile acids are increasingly appreciated as bioactive molecules and important end products of cholesterol metabolism. While they have been identified as key factors in lipid emulsification and absorption due to their detergent properties. bile acids have also been shown to act as signaling molecules and intermediates between the host and the gut microbiota. To investigate bile acid functions in humans, an advanced platform for high throughput analysis is essential. Herein, we developed the analytical method of cholic acids following simple one step protein precipitation from biological sample by UPLC-MS/MS. MRM ions was m/z=407.2 for cholic acid. The R2 of calibration curves provided 0.9995 in the calibration range of 0.005~5 μg/mL. The quantification system was validated with excellent sensitivity that allows quantitative targeted analyses of bile acids. The LOD (0.001 μg/mL), LOQ (0.005 μg/mL), recoveries (96.8~101.3%± 2.7~4.0%) on intra-day assay, and (98.4~111.0%±2.3~3.4%) on inter-day assay achieved resonable validated data for bile acids analyses. The developed method was applied for drawing plasma and bile acid profile in both normal and disease status. Our study is characterized by rapid and simple sample preparation as well as successful application to plasma and bile. These results could be usable for routine diagnostic monitoring of bile acids on human biofluids.

시장획정을 위한 가격 시계열 분석 : 골판지원지 담합사건에의 적용

전성훈 ( Seonghoon Jeon ),정진화 ( Jinhwa Chung ),황윤재 ( Yoon-jae Whang ) 한국산업조직학회 2017 産業組織硏究 Vol.25 No.2

본 논문은 골판지원지 담합사건의 가격자료와 시계열 분석기법을 활용하여 관련 상품시장의 획정에 대한 시사점을 도출한다. 가격 시계열 분석은 여러 재화가 하나의 시장에 속한다면 그 재화들의 가격은 동일한 양상으로 변동할 것이라는 착안에 기초한다. 그러나 이러한 시장획정 방법은 두 재화에 공통적으로 영향을 주는 요인이 존재할 경우 가격 시계열사이의 관련성이 과장될 가능성이 있다는 한계가 있다. 이를 극복하기 위하여, 본 분석에서는 가격에 영향을 주는 다양한 공통요인을 통제한 후, 골판지와 이면지ㆍ골심지 가격의 통계적 관계를 분석하였다. 본 연구의 결과에 따르면, 계절, 추세 및 비용요인 등 공통요인을 통제하였을 때 두 가격 사이의 상관계수는 매우 낮게 나타났다. 또한 Granger 인과관계 검정결과, 공통요인이 통제된 표면지와 이면지ㆍ골심지 가격은 상호인과관계가 존재하지 않아 두 가격이 외생적으로 결정됨을 시사한다. 더구나 두 가격 간에는 장기적 균형관계인 공적분 관계도 존재하지 않는 것으로 나타났다. 결국 이러한 가격검정의 결과는 두 재화가 동일한 시장에 속하지 않는다는 점을 시사한다. In this paper we investigate time-series propeties of the price data of a collusion case in the corrugated paperboard industry in Korea, and try to derive some implications on the relevant market definition. The basic idea is that the prices of several products in a single market should move similarly over time. But the limitation inherent in such methodologies is that common factors in two product markets might magnify the extent of true associations among the price data. We control various common factors affecting the co-movement of two prices to circumvent this problem, and perform a statistical anlysis on the time series of the prices of surface paper and backside/corrugated paper in the paperboard industry. The correlation coefficients of two price data are very low after controlling for common factors such as seasonality, trend, costs, etc. Also, the Granger test result shows that the two price time-series after controlling common factors do not cause each other, suggesting that they are determined exogenously. Moreover, there is no statistically significant evidence of co-integration in the two prices, which would be necessary for a long-term equilibrium relationship. Overall, these results suggest that the two products do not belong to the same market.