Long-Term Variation of the Spin Period of a Magnetic Cataclysmic Variable, MU Camelopardalis

윤아미,김용기,최철성 한국우주과학회 2011 Journal of Astronomy and Space Sciences Vol.28 No.1

Results of an analysis of 11 nights of R-filter CCD photometry data of an intermediate polar MU Camelopardalis (MU Cam) obtained at the Korean 1.0 m telescope at Mt. Lemmon are reported. After checking the spin period with our data,P_(spin) =0.^d01373801(59), we compiled the reported data of maxima timing and an O-C diagram analysis has been carried out to understand the spin period variation. A significant spin period variation was detected, and fitting the O-C points to a cubic parabola led to an ephemeris of BJD_(max)=2453682.4178(94)+0.0137380(13)E-2.07(55) ×10^(−11)E^2 +2.28(52) ×10^(−15)E^3 . The torque experienced by the magnetic compact star accreting in a disk is estimated as τ ≈ 1.815×10^(35)gcm^2 / s^2 in a simple approximation in order to show how important monitoring the period variation is. Thus we conclude that monitoring the long-term spin period variation will help to understand the physical condition of magnetic compact stars.

CP4 EPSPS 검출을 위한 단클론 항체 생산

윤아미,김일룡,최원균 한국환경생물학회 2021 환경생물 : 환경생물학회지 Vol.39 No.4

Agrobacterium tumefaciens strain CP4 유래 5-enolpyruvylshikimate- 3-phosphate synthase (EPSPS) 유전자를 포함하는 유전자변형생물체 (Living modified organism, LMO)가 개발되었다. 이 같은 LMO는 국내 승인되어 사료용, 식품용, 가공용으로 이용 중이다. 간이면역 검사키트 개발을 위해서는 고효율의 단클론 항체 개발이 필수적이다. 본 연구에서는 대장균 BL21 (DE3)에서 재조합 CP4 EPSPS 단백질을 정제하였으며 SDS-PAGE와 MALDI-TOF MS 분석으로 단백질 특성을 분석하였다. 단클론 항체 제작은 ㈜앱 클론의 SOP 매뉴얼에 따라 진행하였다. 본 연구 결과 5개의 단클론 항체 클론 (2F2, 4B9, 6C11, 10A9, 10G9)를 확보하였다. 5종의 단클론 항체의 효율과 특이도 검정을 위해서 LM 면화 추출액을 이용한 western blotting 분석을 실시하였다. 모든 단클론 항체는 CP4 EPSPS를 함유하는 MON1445와 MON88913을 특이적으로 검출하였으며 비변형 면화 및 타종의 LM 면화에서는 검출되지 않았다. 이러한 결과들을 바탕으로 CP4 EPSPS 단클론 항체는 LMO 에 함유된 CP4 EPSPS 단백질을 타겟으로 항체 기반 검출법 개발에 활용될 것으로 사료된다. In this study, we described the production of an antibody to living modified organisms (LMOs) containing the gene encoding for 5-enolpyruvylshikimate-3- phosphate synthase (EPSPS) from Agrobacterium tumefaciens strain CP4 EPSPS provides resistance to the herbicide glyphosate (N- (phosphonomethyl) glycine). These LMOs were approved and have recently been used in the feed, food production, and processing industries in South Korea. Highly efficient monoclonal antibody (mAb) production is crucial for developing assays that enable the proper detection and quantification of the CP4 EPSPS protein in LMOs. This study describes the purification and characterization of recombinant CP4 EPSPS protein in E. coli BL21 (DE3) based on sodium dodecyl sulfate-polyacrylamide gel electrophoresis (SDS-PAGE) and matrixassisted laser desorption/ionization time-of-flight mass spectrometry. The production of mAbs was undertaken based on the standard operating procedure of Abclon, Inc. (South Korea), and the purity of the mAbs was assessed using SDS-PAGE. The following five mAb clones were produced: 2F2, 4B9, 6C11, 10A9, and 10G9. To verify the efficiency and specificity of the five developed mAbs, we performed Western blotting analysis using the LM (living modified) cotton crude extracts. All mAbs could detect the CP4 EPSPS protein in the LM cotton traits MON1445 and MON88913 with high specificity, but not in any other LM cottons or non-LM cottons. These data indicate that these five mAbs to CP4 EPSPS could be successfully used for the further development of antibody-based detection methods to target CP4 EPSPS protein in LMOs.

우주산업 클러스터 발전 방안에 대한 고찰

윤아미(AMi YUN),임종빈(Jongbin Im) 한국항공우주학회 2023 한국항공우주학회 학술발표회 논문집 Vol.2023 No.4

ISECG 국제 달 탐사 시나리오 업데이트 주요 내용 및 시사점

윤아미(Yun AMi) 한국항공우주학회 2023 한국항공우주학회 학술발표회 논문집 Vol.2023 No.11

유전자변형 면화 MON757, MON88702, COT67B, GHB811의 동시검출법 개발

김일룡,설민아,윤아미,이중로,최원균 한국환경생물학회 2021 환경생물 : 환경생물학회지 Vol.39 No.4

면화는 중요한 섬유 작물로 종자는 가축의 사료로 사용 된다. 작물 생명공학은 농업 분야에서 농업적 형질과 질을 향상시키기 위해 활용되어져 왔다. 국내 식품, 사료, 가 공 제품에 유전자변형 (LM) 면화의 사용이 증가함에 따라 환경으로의 LM 면화의 비의도적 유출 또한 증가하고 있다. LMO 모니터링 사업에서 수집된 LM 면화를 검정하기 위하여 국내 수입 승인된 LM 면화의 검출법 개발이 필요하다. 본 연구에서는 LM 면화 MON757, MON88792, COT67B, GHB811 4종을 대상으로 동시검출법을 개발하였다. 이벤트에 대한 유전 정보는 유럽 JRC와 농림축산검역본부에서 확보하였다. LM 면화의 동시검출법 개발을 위해 이벤트 특 이적인 프라이머를 설계하였으며 특이적인 증폭을 확인하였다. 특이도 검정, 무작위 표준물질 혼합물 분석, 검출한계 분석을 통하여 동시검출법의 정확도와 특이도를 검증하였다. 그 결과 본 동시검출법은 각각의 이벤트를 검출할 수 있으며 LM 표준물질을 활용하여 특이도를 검정하였다. 또한 무작위 표준물질 조합도 정확하게 검출할 수 있다. 검출한 계 분석에서는 25 ng의 미량의 주형 DNA로 단회 분석으로 검출이 가능하다. 결론적으로 4종의 LM 면화 동시검출법을 개발하였으며 LM 면화 자생체 분석에 활용될 것으로 사료 된다. Cotton is an important fiber crop, and its seeds are used as feed for dairy cattle. Crop biotechnology has been used to improve agronomic traits and quality in the agricultural industry. The frequent unintentional release of LM cotton into the environment in South Korea is attributed to the increased application of living modified (LM) cotton in food, feed, and processing industries. To identify and monitor the LM cotton, a method for detecting the approved LM cotton in South Korea is required. In this study, we developed a method for the simultaneous detection of four LM cotton varieties, MON757, MON88702, COT67B, and GHB811. The genetic information of each LM event was obtained from the European Commission-Joint Research Centre and Animal and Plant Quarantine Agency. We designed event-specific primers to develop a multiplex PCR method for LM cotton and confirmed the specific amplification. Using specificity assay, random reference material (RM) mixture analysis and limit of detection (LOD), we verified the accuracy and specificity of the multiplex PCR method. Our results demonstrate that the method enabled the detection of each event and validation of the specificity using other LM RMs. The efficiency of multiplex PCR was further verified using a random RM mixture. Based on the LOD, the method identified 25 ng of template DNA in a single reaction. In summary, we developed a multiplex PCR method for simultaneous detection of four LM cotton varieties, for possible application in LM volunteer analysis.

Performance Analysis of Sensor Systems for Space Situational Awareness

최은정,조성기,조정현,박장현,정태진,박재우,전호철,윤아미,이용희 한국우주과학회 2017 Journal of Astronomy and Space Sciences Vol.34 No.4

With increased human activity in space, the risk of re-entry and collision between space objects is constantly increasing. Hence, the need for space situational awareness (SSA) programs has been acknowledged by many experienced space agencies. Optical and radar sensors, which enable the surveillance and tracking of space objects, are the most important technical components of SSA systems. In particular, combinations of radar systems and optical sensor networks play an outstanding role in SSA programs. At present, Korea operates the optical wide field patrol network (OWL-Net), the only optical system for tracking space objects. However, due to their dependence on weather conditions and observation time, it is not reasonable to use optical systems alone for SSA initiatives, as they have limited operational availability. Therefore, the strategies for developing radar systems should be considered for an efficient SSA system using currently available technology. The purpose of this paper is to analyze the performance of a radar system in detecting and tracking space objects. With the radar system investigated, the minimum sensitivity is defined as detection of a 1-m2 radar cross section (RCS) at an altitude of 2,000 km, with operating frequencies in the L, S, C, X or Ku-band. The results of power budget analysis showed that the maximum detection range of 2,000 km, which includes the low earth orbit (LEO) environment, can be achieved with a transmission power of 900 kW, transmit and receive antenna gains of 40 dB and 43 dB, respectively, a pulse width of 2 ms, and a signal processing gain of 13.3 dB, at a frequency of 1.3 GHz. We defined the key parameters of the radar following a performance analysis of the system. This research can thus provide guidelines for the conceptual design of radar systems for national SSA initiatives.

우주개발 확대에 따른 국가우주개발 거버넌스 개편 방안

안형준(Hyoung Joon An),임종빈(Jongbin Leem),박강민(Kangmin Park),권윤영(Yoonyoung Kwon),신상우(Sangwoo Shin),백서인(Seoin Baek),김종립(Jonglib Kim),강희종(Heejong Kang),김지선(Jiseon Kim),윤아미(Ami Yoon),민지혜(Jihye Min) 과학기술정책연구원 2022 정책연구 Vol.- No.-