http://chineseinput.net/에서 pinyin(병음)방식으로 중국어를 변환할 수 있습니다.
변환된 중국어를 복사하여 사용하시면 됩니다.
Choi, Mira,Choi, A Young,Ahn, Soo-Yeon,Choi, Kwon-Young,Jang, Kyoung-Soon Korean Society for Mass Spectrometry 2018 Mass spectrometry letters Vol.9 No.3
In this study, the chemical composition of bacterial melanin isolated from the Streptomyces glaucescens strain was elucidated by ultra-high-resolution Fourier transform ion cyclotron resonance (FT-ICR) mass spectrometry. Ultra-high-resolution mass profiles of the microbial melanin product were acquired using a 15 Tesla FT-ICR mass spectrometer in positive and negative ion modes via electrospray ionization to obtain more complete descriptions of the molecular compositions of melanin-derived organic constituents. A mass resolving power of 500,000 (at m/z 400) was achieved for all spectra while collecting 400 scans per sample with a 4 M transient. The results of this analysis revealed that the melanin pigment isolated from S. glaucescens predominantly exhibits CHON and CHO species, which belong to the proteins class of compounds, with the mean C/O and C/N ratios of 4.3 and 13.1, thus suggesting that the melanin could be eumelanin. This analytical approach could be utilized to investigate the molecular compositions of a variety of natural or synthetic melanins. The compositional features of melanins are important for understanding their formation mechanisms and physico-chemical properties.
AlgeoMath를 활용한 초등 도형 과제의 도구화 스킴 분석
최미라(Mira Choi),이예진(Ye-Jin Lee),최은미(Eunmi Choi),최인용(Inyong Choi) 대한수학교육학회 2024 학교수학 Vol.26 No.2
최근 초등 도형 학습에서 동적 기하 환경(DGE)의 활용에 대한 관심이 증가하고 있다. 본 연구에서는 도구적 관점을 이용하여 DGE를 활용하는 초등 도형 과제를 분석하고, 초등학생들이 직면할 수 있는 개념적 및 기술적 어려움을 도출하고자 하였다. 이를 위해 교과서 및 선행 연구를 분석하여 한국형 DGE인 AlgeoMath를 활용한 과제를 추출하고, 실습을 통해 과제별 도구화 스킴을 분석하였다. 분석 결과, 일부 도구의 용어 및 기호가 초등 교육과정에 부합하지 않거나 수학적 오류를 포함하고 있었으며, 함수적 관점의 이해나 중등 기초 작도를 요구하는 일부 스킴은 초등학생에게 개념적 및 절차적 어려움을 줄 수 있음을 확인하였다. 또한, 정밀하게 구현된 변환 도구가 비형식적이고 직관적으로 학습하는 초등 평면도형의 이동에 적합하지 않음을 확인하였다. 마지막으로, 객체의 독립성과 종속성, 숨기기 등 DGE 고유의 특성과 AlgeoMath의 기능적 한계 및 오류가 학생들에게 어려움을 초래할 수 있음을 확인하였다. 연구 결과를 토대로, AlgeoMath를 활용한 초등 수학 수업에 관한 교수학적 시사점 및 초등용 DGE의 기능 구성에 관한 시사점을 제안하였다. Recently, there has been increasing interest in the use of Dynamic Geometry Environments (DGE) in elementary geometry learning. This study aims to analyze elementary geometry tasks utilizing DGE from an instrumental perspective and to identify the conceptual and technical difficulties that elementary students may encounter. To achieve this, we analyzed textbooks and previous studies to extract tasks that utilize the Korean DGE, AlgeoMath, and conducted practical exercises to analyze the instrumentation schemes for each task. The analysis revealed that some terms and symbols of the tools were not aligned with the elementary curriculum or contained mathematical errors, and that some schemes requiring an understanding of functional perspectives or basic constructions in secondary mathematics could present conceptual and procedural difficulties for elementary students. Furthermore, we found that precisely implemented transformation tools were not suitable for the informal and intuitive learning of elementary plane figure movements. Finally, it was confirmed that the inherent characteristics of DGE, such as the independence and dependence of objects and the hiding feature, as well as the functional limitations and errors of AlgeoMath, could pose challenges for students. Based on these findings, the study suggests pedagogical implications for elementary mathematics lessons using AlgeoMath and provides insights into the functional composition of DGE for elementary use.
A Case of Primary Cutaneous CD4 Positive Small/medium T Cell Lymphoma
Mira Choi,Se Young Park,박현선,Hee Jin Byun,조광현 대한피부과학회 2011 Annals of Dermatology Vol.23 No.1
Primary cutaneous CD4 positive small/medium T cell lymphoma (PCSM-TCL) is a provisional entity in the new WHO-EORTC classification for cutaneous lymphoma, and it is a rare disease with a favorable clinical course. PCSM-TCL may present with different clinical and pathologic features associated with the biologic behavior of the disease. Herein we report on a 63-year-old woman with multiple, multifocal,erythematous to violaceous papules and plaques that progressed despite local radiotherapy. (Ann Dermatol 23(1)76∼80, 2011)
Choi, Yuri,Park, Mira,Kyoung Shin, Hye,Liu, Yanan,Choi, Ja-Wun,Nirmala, Rajkumar,Park, Soo-Jin,Kim, Hak-Yong Elsevier 2014 Materials letters Vol.123 No.-
Polyacrylonitrile (PAN)-based electrospun nanofibers (NFs) were irradiated using an electron beam. 1% hydrogen peroxide (H2O2) solution was sprayed during Electron Beam Irradiation (EBI) as a further oxidative stabilization process. Fourier transform infrared spectroscopy (FT-IR) and X-ray Diffraction (XRD) of electrospun PAN NFs indicated that the transformation of C=N to C=N groups was accelerated by spraying 1% H2O2 solution. EBI-H2O2 stabilized PAN NFs reduce the onset temperature, extends the exothermic reaction, and improves the stabilization at a significantly lower dose of irradiation (50 kGy) as a result of cyclization and oxidation of PAN molecules caused by 1% H2O2 solution. (c) 2014 Elsevier B.V. All rights reserved.