A comparison of language learning strategies between bilingual and monolingual Koreans

김민정 Hankuk University of Foreign Studies 2008 국내석사

The interest in language learning strategies has heightened with the shift of pedagogic focus from teacher-centered approaches to the learner's active role in language learning. Accordingly, this study centers upon the language learning strategies of bilingual and monolingual language learners residing in Korea. There are three purposes of this research. The first purpose is to examine language learning strategies of bilingual and monolingual Koreans according to language skill areas such as Listening, Vocabulary, Speaking, Reading and Writing. The second goal is to compare the language learning strategies between genders within the two groups. The final purpose is to look into the language learning strategies that had been employed by bilingual Koreans in the process of becoming a bilingual. The subjects of this study were 80 graduates and undergraduates of Hankuk University of Foreign Studies located in Seoul. The researcher divided the monolingual group into upper and lower monolingual groups depending on their self-reported TOEIC scores. In order to examine the reliability of the survey, SPSS for Windows 12.0 was used. In order to complement for the unequal proportion of bilingual and monolingual learners, the researcher conducted retrospective interviews with 4 bilinguals. The results are as follows: First, there were significant differences in language learning strategy use between the bilingual and the upper-monolingual group in "Strategies used for when words and grammatical structures are not understood" in the Reading skill area. Bilinguals proved to employ more strategies compared to monolinguals. Between the bilingual and the lower-monolingual group, significant differences were revealed in "Strategies to prepare to listen to conversation in the target language" within the Listening skill area and "Strategies used for when words and grammatical structures are not understood" within the Reading skill area. Differences also existed in "Strategies for basic writing" and "Strategies to use after writing a draft of an essay or paper". Second, in terms of strategy use among the learners, females were using more strategies than male learners in both groups. Overall, female learners employed more strategies in "Strategies to increase exposure to the target language," "Strategies to become familiar with the sounds in the target language" and "Strategies for when I do not understand some or most of what someone says in the target language" within the Listening skill area. Within the Writing skill area, females showed more strategy use in "Strategies to use after writing a draft of an essay or paper." Within the bilingual group, females used more strategies in "Strategies to increase exposure to the target language" whereas females in the monolingual group adopted more strategies in "Strategies to become familiar with the sounds in the target language". Third, through retrospective interviews with 4 bilinguals, the bilinguals reported that they had pretended to understand when listening, and had become quickeyed by exerting effort to understand the situational context through the interlocutor's uses of keywords or gestures. In terms of Vocabulary, bilinguals showed a tendency to focus on prefixes and suffixes of a word. They had focused more on idioms rather than individual words. Moreover, what was most important was that they tried to practice what they had learned right away. In terms of Reading, bilinguals reported to look up words in dictionaries when they were beginners and they guessed words from contextual clues once they had reached a certain level of proficiency. In the Writing skill area, the general trend among bilinguals was that they first did their writings in their first language or they copied material from existing texts and rephrased them. This study proved that there were differences in the use of language learning strategies between bilingual and monolingual language learners and that female learners applied more strategies compared to males. The reports of retrospective interviews with bilinguals may hopefully shed light on monolinguals learning languages in EFL environments. Accordingly, more researches focusing on the differences between bilinguals and monolinguals are required with a larger number of bilingual subjects with a longer duration of research period. Not only that, but detailed descriptive analyses will be helpful along with case studies for more elaborate results within the field.

Taekwondo coach's servant leadership and athletic performance : the mediating effects of leader trust and leader commitment

김민정 Graduate School, Yonsei University 2011 국내석사

In every sport organization, leadership is very important to influence athletes and their performance. The purpose of this study was to examine the effects of Taekwondo coach’s servant leadership on athlete performance mediated through leader trust and leader commitment. The subjects were Taekwondo athletes of professional teams, and total 183 surveys, which were collected by using a complete enumeration method, were used for the actual analysis. The questionnaire was composed with 46 questions of servant leadership, leader trust, leader commitment, athletic performance, based on precedent studies and demographic information. For the analysis of data, frequency analysis, confirmatory factor analysis, reliability analysis, model fit evaluation, and path analysis were used. Also, to verify mediating effect, the bootstrapping method was used. The significant level was set at α=.05 and the results of this study are as follows. First, coach's servant leadership had no direct effect on athletic performance. Second, coach's servant leadership and leader commitment had positive effects on leader trust. Third, leader trust had positive effect on athletic performance. Forth, leader commitment had no positive effect on athletic performance. Fifth, leader trust mediated between coach's servant leadership and athletic performance. Lastly, leader commitment not mediated between coach's servant leadership and athletic performance. Based on these results, for improving athletic performance, Taekwondo coaches should have servant mind. On top of that, coaches should consider methods to let players have leader trust.

(The) study of panel-based integrative analysis of Korean colorectal cancer cohort

김민정 Graduate School, Yonsei University 2021 국내박사

Colorectal cancer (CRC) is a highly heterogeneous type of cancer and exponential productions of whole genome sequencing data in cancer have broaden genome-wide associations between genomic alterations and clinical phenotypes and contributed to better understanding of cancer. In an effort to discover the genetic characteristics of Korean-specific CRC patients, we present 151 mutation profiles through sophisticately curated targeted gene sequencing (TGS) panel. Designed to contain genes essential to CRC development and progression, our TGS panel shows potentials to discover recurrent hypermutations in coding and noncoding regions of 92 genes. Our results show high-sensitive variant detection performance down to 0.1% allele frequency (AF). In addition, with >70% of on-target rates and >200X deep sequencing while eliminating minimized sequencing errors using unique molecular identifier (UMI) techniques, we present exceedingly optimized experimental and analytical performances. Based on technical optimization, TGS panel successfully discriminated somatic mutations with clinical implications and found novel variants with low AFs in regulatory regions. Furthermore, we also propose the associated functional transcriptomic changes by integrative analyses of consensus molecular subtypes (CMS). We evaluated CMS classification and most of discoveries are highly consistent with previous findings in other studies. In detail, all MSI-H patients classified in CMS1, hypermutations in DNA damage repair genes and Janus kinase (JAK) - signal transducer and activator of transcription (STAT) activation in MSI-immune CMS1 in our cohort. We assumed that FGF19 hypermutation in CMS1-enriched tumor location could possibly be activated in FGF19-FGFR4 signaling pathway and this correlates with the transcriptomic changes that the genes in downstream of FGF19-FGFR4 signaling such as JAK2 and AKT1 are also upregulated in CMS1. Lastly, we systemized panel report system which offers direct path from researchers to clinicians. With user-friendly interfaces and straightforward visualization of the screens, patient-specific mutation profiles would give clinicians helpful information for decision-making. In conclusion, our study addresses new appoach of understanding genetic abberations with CMS, tumor location and its funtional interpretation. Unlike many other studies which have clear limitations on applying discovered results in clinical fields, we propose straightforward scheme with a statistical technique for better understanding of our discoveries and easier application to real-world medicine. These integrative analyses of Korean CRC suggest that our TGS panel possesses many applicable future aspects such as the utilization of liquid biopsy samples or application to prognostic purpose. We strongly believe that our TGS panel provides promising applications in both clinical and research settings for precision medicine. 대장암은 국내에서 발병율과 사망률이 매우 높은 암종이다. 이러한 대장암은 암의 진행 단계에 따라 발견되는 변이들이 특성을 이루고, 이를 바탕으로 대장암의 체성 변이 (somatic mutation)에 대하여 다양하게 연구되고 있다. 특히, 차세대 염 기서열 분석 기법 (Next-generation sequencing) 기반의 타겟티드 시퀀싱(targeted sequencing) 방법을 활용하여 질병의 진단 및 예후 마커로서 활용가치가 있는 변이를 찾고 이를 진단, 예후 및 치료반응성 예측 등에 활용하려는 연구가 많이 이루어지고 있다. 본 연구는 미국이나 유럽 코호트 중심의 유전체 분석에서 벗어나 한국인 대장암 코호트에서 특징적으로 발견되거나 유전자 발현에 영향을 주는 변이들을 효과적으로 검출하고자 하였다. 이 때, hybrid-capture 기반의 타겟티드 시퀀싱을 이용하 여, 대장암의 치료 타겟이 되는 유전자들과 고빈도의 변이가 발견되는 유전자들의 발현 부위에 대한 변이를 검출하였다. 뿐만 아니라, 임상치료 약물의 타겟이 되는 유전자들의 경우 해당 유전자의 조절 부위 (regulatory region)의 변이를 발견하고, 조절 부위의 변이들을 높은 민감도로 발견할 수 있었다. 또한, 대장암에서는 전사체 기반으로 밝혀진 특징에 따라 대장암을 4가지 Consensus molecular subtype(CMS)로 그룹화하고 이를 대장암의 이해와 치료 효과를 높이고자 하는 연구가 활발히 진행되고 있다. 이에 착안하여 CMS의 특성과 유전자 변이와의 상관관계를 분석하여 발견된 변이가 유전자 발현 양상과 그 표현형에 어떠한 영향을 미치는지 통계학적으로 접근하고자 하였다. 또한, 마지막으로, 이렇게 환자별 변이 포 트폴리오를 구축하여 생산한 데이터와 분석 결과를 연구 레벨에서 그치지 않고, LIMS를 통한 리포트 시스템을 구축하여 임상 치료에 적극 활용할 수 있는 발판을 마련하여 정밀의료를 현실화하고자 하였다. 본 연구는 대장암의 표적치료를 위 한 기반 연구들이 활성화될 수 있는 장을 마련한 데에 의의가 있다

Molecular and developmental functions of lateral organ boundaries domain(LBD)10, LBD16 and LBD18 transcription factors in Arabidopsis thaliana

김민정 Chonnam National University 2015 국내박사

식물체 특이적 전사조절인자인 LATERAL ORGAN BOUNDARIES DOMAIN/ASYMMETRIC LEAVES2-LIKE (LBD/ASL) 유전자 군은 식물체의 다양한 생장, 발달을 조절한다. LBD 단백질들은 N-말단부위에 CX2CX6CX3C 간격을 지닌 네 개의 cysteine motif, Gly-Ala-Ser 블록 (GAS 블록), 그리고 LX6LX3LX6L 간격의 네 개의 leucine을 포함하는 coiled-coil 구조로 구성된 보존적인 LOB도메인을 가지고 있다. 본 연구에서는 LBD10, LBD16, 그리고 LBD18전사활성인자의 분자 및 식물발달학적 기능을 규명하는 것에 중점을 두었다. LBD 단백질들은 세포 내 핵에 위치하지만 핵으로의 이동을 책임지는 명백한 consensus sequence는 밝혀지지 않았다. 제 1장에서는 애기장대 원형질체를 이용하여 LBD16 단백질의N- 혹은 C-말단 결손 폴리펩타이드 단편과 기본 아미노산이 변형된 폴리펩타이드를 이용한 실험으로 LBD 단백질의 세포 내 핵으로의 위치를 책임지는 모티프를 결정하였다. LBD16 단백질의 세포 핵 위치 신호서열(NLS)은 coiled-coil 모티프 내의 기본 아미노산과 C-말단 부위의 유사 단립형 NLS를 포함한 두 개의 집락으로 구성된 비전형 세포 핵 위치 신호서열임을 입증하였다. 이러한 결과는 LBD단백질들의 세포 핵으로의 이동에 있어서 coiled-coil 모티프와 C-말단의 다양한 구조적 모티프의 중요성을 강조한다. 제 2장에서는 LBD18 단백질의 DNA 결합 특이성을 결정함으로써 전사활성인자로서 LBD18 단백질의 생화학적 기능에 관해 다루었다. LBD18 단백질은 세포벽 이완 인자인EXPANSIN14 (EXP14) 유전자의 프로모터에 염기서열 특이적으로 직접 결합함으로써 EXP14 유전자의 활성을 조절하였다. EXP14 유전자의 프로모터에 존재하는22-bp로 구성된 올리고핵산염은 LBD18 단백질을 위한 최소 결합부위로 결정되었고 LBD18 단백질의 LOB 도메인을 포함하는 117개의 아미노산으로 구성된 폴리펩타이드 부분이 DNA 결합에 중요한 부위임을 알았다. 또한 본 연구에서는 애기장대 엽육세포의 원형질체를 이용한 유전자 발현분석을 통해 LOB 도메인의 보존된 4개의 cysteine 모티프 중 첫번째 cysteine이 LBD18의 DNA 결합 활성에 영향을 미치며, 전기영동 이동분석에서 아연화합물들에 의한 LBD18 단백질의 형태변화를 관찰하였다. Microarray를 이용한 애기장대 유전체 분석에서, 다양한 유전자들의 발현 변화를 제공함으로써 LBD18 단백질의 DNA 결합 전사활성인자로서의 특징을 뒷받침하였다. 종합적으로, LBD18 단백질은 다양한 표적 유전자를 조절하기 위하여 LOB 도메인을 포함한 DNA 결합 모티프를 가지는 특이적 DNA 결합 전사활성인자이다. 제 3장에서는, 수 배우체 발달 과정 중 LBD10 유전자의 기능 특성에 관해 알아보았다. ProLBD10:GFP:GUS 형질전환 식물체를 이용한 GUS 표지유전자 발현분석과GFP 형광 단백질 분석, 그리고 lbd10 heterozygous의 유전체 전이 분석을 통해, LBD10 유전자는 수 배우체 특이적 기능이 있음을 입증하였다. 이러한 결과와 일치하게, lbd10 돌연변이체와 LBD10 유전자의 우성억제자 버전으로 이용한 ProLBD10:LBD10:SRDX/lbd10 형질전환 식물체의 성숙한 꽃가루에서 이중세포핵과 작은 크기의 삼중세포핵을 가진 비정상적인 형태의 꽃가루를 관찰하였다. 이후에 LBD10유전자의 생물학적 역할을 조사하기 위하여, lbd10 lbd27 이중 돌연변이체를 제작하였다. 흥미롭게도 lbd10 lbd27 이중 돌연변이체의 꽃가루는 각 단일 돌연변이체와 비교하였을 때, 극심하게 찌그러진 형태의 꽃가루를 보였다. 이러한 발견은 LBD10 유전자와 LBD27 유전자가 꽃가루 발달에 있어서 중요한 역할을 수행한다는 것을 의미한다. lbd10, lbd27, 그리고 lbd10 lbd27 이중 돌연변이체에서 발달 중인 꽃가루의 표현형 분석을 통해, LBD10 유전자는 소포자 극지화와 생식세포 분열을 위해 LBD27과 함께 작용하지만 꽃가루 성숙 과정에서는 서로 다른 역할을 수행한다는 것을 알았다. 또한 LBD10과 LBD27 단백질은 식물 세포 내에서 전사활성능력을 보였다. 이러한 사실은 LBD10과 LBD27 단백질이 소포자 발달 조절을 위해 전사활성인자로서 작용할 것임을 나타낸다. 2분자 형광 상보성 분석에서 LBD10과 LBD27 단백질은 세포 내 핵으로 이동을 위해 서로 물리적 결합을 한다는 사실을 보여주었다. 이러한 결과를 모든 점에서 미루어 볼 때 LBD10 유전자는 LBD27 유전자와 상호작용을 통해 꽃가루 발달에 중요한 역할을 수행하는 전사활성인자임을 나타낸다. Lateral Organ Boundaries Domain/Asymmetric Leaves2-Like (LBD/ASL) gene family are transcription factors that regulate diverse aspects in plant growth and development. The LBD proteins have a conserved LOB domain at the N-terminus, comprised of a four-cys motif with CX2CX6CX3C spacing, a Gly-Ala-Ser block (GAS block), and a predicted coiled-coil structure with four leucines in LX6LX3LX6L spacing. In the present study, I focused on the molecular and developmental functions of LBD10, LBD16 and LBD18 as transcription factors. In the first chapter, the motifs responsible for nuclear localization of LBD16 were determined by using a series of N- or C-terminal deletion polypeptide fragments and the polypeptides harboring changes in the basic amino acids of LBD16 in Arabidopsis mesophyll protoplasts. Two distinct domains with basic amino acid residues in the coiled-coil motif and a monopartite-like NLS in the C-terminal region of LBD16 were determined as NLS responsible for nuclear targeting. These results highlight the importance of the coiled-coil and variable structural motifs in the C-terminus for nuclear localization of LBD proteins. In the second chapter, I addressed the biochemical function of LBD18 as a DNA-binding transcription factor by determining its DNA-binding specificity. I showed that LBD18 activates EXPANSIN14 (EXP14), encoding the cell wall loosening factor by directly binding to a specific promoter element in vivo as well as in vitro by using Electrophoretic Mobility Shift Assays (EMSA) and Chromatin ImmunoPrecipitation (ChIP) assays. The 22-bp oligonucleotide in the EXP14 promoter was determined as a minimal binding region for LBD18. The polypeptide region comprising 117 amino acids including the LOB domain of LBD18 was determined as the DNA binding domain. The 1st cysteine of a four-cys motif in the LOB domain was suggested a residue affecting the DNA binding activity of LBD18 by using transient gene expression assay with protoplasts. Zinc ions were shown to affect DNA-binding behaviour of LBD18. Microarray analysis was used to identify a variety of putative direct target genes of LBD18. Collectively, these results suggest that LBD18 is a specific DNA-binding transcription factor harboring a DNA-binding motif including a LOB domain to regulate various target genes. In the third chapter, I showed that LBD10 interacts with LBD27 to control pollen development. Histochemical GUS assay and fluorescence analysis of the ProLBD10:GFP:GUS transgenic Arabidopsis and genetic transmission assay of +/lbd10 demonstrated that LBD10 has a gametophyte specific function. Consistent with these observation, aberrant microspores such as bicellular and smaller tricellular pollen in lbd10 and ProLBD10:LBD10:SRDX/lbd10, a dominant negative version of LBD10 were found at the mature pollen stage. To further investigate the biological roles of LBD10, lbd10 lbd27 double mutants were generated. The severely shriveled and unviable pollen were observed in the lbd10 lbd27 mutants. These finding suggested that LBD10 and LBD27 play a crucial role in pollen development. Phenotypic analysis of developing microspores in lbd10, lbd27, and lbd10 lbd27 indicated that LBD10 functions with LBD27 to regulate the microspore polarization and asymmetric cell division, but plays a distinct role in pollen maturation. LBD10 and LBD27 exhibited transcriptional activities in Arabidpsis protoplasts. Bimolecular Fluorescence Complementation (BiFC) assays demonstrated that LBD10 and LBD27 interact with each other for nuclear localization. Collectively, these results suggest that LBD10 plays a pivotal role in pollen development in combination with LBD27.

Development of retargeted adenovirus to tumor-associated antigen sialyl Lewis X

김민정 Graduate School, Yonsei University 2002 국내석사

Sialyl Lewis X (sLewX)는 종양관련항원으로 암세포가 내피세포에 부착될때 리간드로 작용하여 암세포의 전이를 돕고, sLewX 발현이 증가될수록 위암, 대장암, 폐암, 난소암과 같은 다양한 암의 예후가 나쁘다는 보고가 있다. 따라서 우리는 sLewX에 대한 in vitro random phage display법을 이용하여 20여개의 phage를 분리하여 sLewX 특이적 결합능과 펩타이드들의 염기서열을 확인하였고, sLewX가 많이 발현되는 암세포에 선택적으로 감염되는 아데노바이러스벡터를 개발하였다. 특정조직 및 세포로 표적화된 아데노바이러스를 개발하기 위해서는 바이러스 본래의 세포수용체와의 결합능을 없애고, 새로운 세포수용체와의 결합능을 첨가해주어야 한다. 우리는 CAR 결합능이 배제된 아데노바이러스인 YKL-1/420A를 개발하였고, 그 결과 비교군의 아데노바이러스에 비해 유전자 전달효율이 급격히 감소하는 것을 확인하였다. 여기에 phage display법으로 분리한 펩타이드 중 3개를 선택하여 바이러스의 fiber C 말단에 결합시켜 YKL-1-420A/7mer, YKL-1-420A/12mer, YKL-1-420A/p30을 만들었다. YKL-1-420A/p30은 YKL-1-420A에 비해 10-100배 가량 증가된 세포살상능력을 보였으며, xenograft 종양모델에 처치한 결과 YKL-1-420A에 비해 급격하게 종양크기가 감소하였다. 따라서 아데노바이러스의 재표적화는 유전자치료에 매우 유용하게 이용될 수 있으며 특히 sLewX에 특이적으로 결합하는 아데노바이러스인 YKL-1-420A/p30은 세포 특이적이며 CAR에 비의존적인 유전자전달을 가능하게 하였다. Sialyl Lewis X (sLewX) is a tumor-associated carbohydrate antigen. Several studies indicate that sLewX serves as a ligand in the adhesion of cancer cells to endothelial cells, resulting in hematogenous metastasis of human cancer cells. Increased expression of sLewX has been reported to correlate with poor prognoses in various cancers including gastric, colorectal, lung and ovarian cancers. In this perspective, we adopted an in vitro random phage display library panning on sLewX to develop adenoviral vectors capable of the selective infection of the cancer cells with respect to the normal cells. More than 20 individually isolated phage were tested for the ability to bind specifically to sLewX and the sequences of these novel peptides were identified. The development of tissue/cell selective targeting adenovirus requires the generation of adenovirus vectors which lack native receptor binding and additionally contain domains which redirect the vector to tissue/cell specific receptors. Towards this goal, we have generated CAR binding-ablated adenovirus YKL-1/420A using the backbone of an E1B55kD deleted oncolytic adenoviral vector YKL-1. Ykl-1/420A adenovirus exerted dramatic reduction of transduction efficiency compared to control adenovirus. Among the peptides isolated by in vitro random phage display, 3 peptides were chosen and fused to the C-terminus of the fiber protein of YKL-1-420A, generating three sLewX-targeted adenoviruses of YKL-1-420A/7mer, YKL-1-420A/12mer, and YKL-1-420A/p30. YKL-1-420A/p30 exerted about 10-100 times greater cytolytic ability than control adenovirus YKL-1-420A. Furthermore, treatment with YKL-1-420A/p30 significantly suppressed tumor growth in xenograft tumor model when compared with control adenovirus YKL-1-420. Taken together, these studies demonstrate that strategy to alter adenovirus tropism may allow greatly improved utilities of adenovirus for gene therapy applications. In particular, sLewX-specific targeted adenovirus YKL-1-420A/p30 allowed CAR-independent gene delivery as well as cell-specific gene delivery, and showed significant promise as a targeting replicative adenovirus vector in cancer gene therapy.

Zoomed image of contact mammography versus magnification mammography in the diagnosis of microcalcifications with soft-copy full field digital mammography

김민정 Graduate School, Yonsei University 2009 국내박사

연구목적: 이 연구의 목적은 미세석회화의 진단적 정확도와 영상질이 디지털 유방촬영술의 1배 유방촬영술에서 줌했을 때(줌인수 1.3)와 디지털 유방촬영술의 확대유방촬영술에서 유사한지를 알아보고자 한다. 또한 1배 유방 촬영술에서 또 다른 줌인수를 사용한 경우(줌인수 2.0) 확대유방촬영술에서의 미세석회화의 진단적 정확도 및 영상질을 비교하고자 한다.연구대상 및 방법:Part1. 미세석회화의 특성화의 진단수행평가와 영상질에 있어 디지털 유방촬영술에서 1.3배 줌한 방법과 확대유방촬영술 (1.8배 확대인자)의 비교: 유방촬영술에 대한 서로 다른 정도의 경험을 가진 3명의 영상의학과 의사들이 디지털 확대 유방촬영술과 1배 유방촬영술로 모니터에서 상업적으로 사용가능한 방법을 이용한 줌영상을 이용하여 디지털 유방촬영술의 111명의 120 미세석회화 무리를 재고하였다. 각 영상의학과 의사는 악성가능성, 영상의 질과 신뢰수준을 측정하였다. 수행평가는 민감도, 특이도, 양성예측도 음성예측도, 그리고 수신자판단특성곡선 분석으로 평가하였다.Part2. 미세석회화의 특성화의 진단수행평가와 영상질에 있어 디지털 유방촬영술에서 2.0배 줌한 방법과 확대유방촬영술의 비교:유방촬영술에 대한 서로 다른 정도의 경험을 가진 3명의 영상의학과 의사가 185명의 환자에서 병리학적으로 확진된 미세석회화의 디지털 유방촬영술 판독세트를 평가하였다. 판독 세트는 1.8배 확대인자를 갖는 디지털 확대 유방촬영술과 2배 줌인자를 갖는 줌한 영상으로 구성되어있다. 각 영상의학과 의사는 미세석회화병변에 있어서의 유방암의 의심정도를 6단계 척도로 평가하였고. 영상의 질과 그들의 결정에 대한 신뢰정도는 5단계 척도로 평가하였다. 미세석회화의 판독에 따른 결과는 수신자판단특성곡선에 따라 분석하였고 영상의 질과 신뢰수준은 윌콕슨 부호순위검정을 이용하였다. 연구결과:Part1. 미세석회화의 특성화의 진단수행평가와 영상질에 있어 디지털 유방촬영술에서 1.3배 줌한 방법과 확대유방촬영술(1.8배 확대인자)의 비교: 3명의 영상의학과 의사 모두, 1.3배 줌영상에 비해 확대유방촬영영상으로 통계적으로 유의하게 높은 민감도를 보였다 (평균, 92% 대 87%, P<0.05). 또한 확대 유방촬영영상으로 향상된 수신자판단특성곡선을 보였다. 진단의 결정에 있어서의 신뢰수준과 병변특성화에 있어서도 모두 줌영상보다는 확대영상이 우수했다(P<0.0001).Part2. 미세석회화의 특성화의 진단수행평가와 영상질에 있어 디지털 유방촬영술에서 2.0배 줌한 방법과 확대유방촬영술의 비교: 2.0배 줌영상의 곡선하면적은 0.8680으로 확대영상과 유사하다(0.8682, 평균차이에 관한 95% 신뢰구간: -0.02973 에서 0.02934; p=0.9897). 그러나 영상의 질(p<0.001)과 신뢰수준(p<0.001)에 있어서는 확대영상이 줌영상에 비해 우수했다.결론:Part1. 미세석회화의 특성화의 진단수행평가와 영상질에 있어 디지털 유방촬영술에서 1.3배 줌한 방법과 확대유방촬영술(1.8배 확대인자)의 비교: 디지털 확대 유방촬영술은 미세석회와의 특성화시에 진단적 수행을 향상시킨다. 1.3배 줌영상으로 디지털 확대유방촬영술을 대체할 수 없다.Part2. 미세석회화의 특성화의 진단수행평가와 영상질에 있어 디지털 유방촬영술에서 2.0배 줌한 방법과 확대유방촬영술의 비교: 2.0배 줌영상을 이용한 미세석회화의 진단에 있어서 영상의학과 의사의 수행은 확대영상을 이용했을 때와 유사했다. 이와 같이 2.0배 줌영상은 비록 영상의 질과 신뢰수준은 확대영상에 비해 떨어지더라도 미세석회화의 진단에 있어 대체수단으로 쓰일 수 있다. PURPOSE: The purpose of this study was to determine whether the diagnostic accuracy and image quality of microcalcifications of zoomed images from contact mammograms (1.3 of zooming factor) of digital mammography were equivalent to those of soft-copy digital magnification mammography. And this study was also designed to compare the diagnostic accuracy and image quality of microcalcifications when different zooming factors (2.0 of zooming factor) are used in contact mammograms with digital magnification mammography.MATERIALS AND METHODS:I. Comparison of x1.3 zooming method (ZOOM-1.3) and digital magnification view (magnification factor 1.8;MAG) in full-field digital mammography: image quality and diagnostic performance for characterization of microcalcificationsThree radiologists with different levels of experience in mammography reviewed 120 microcalcification clusters in 111 patients with a full field digital mammography (FFDM) system using digital magnification mammogram (MAG) images and zoomed images from contact mammography (ZOOM) with commercially available zooming systems on monitors. Each of three radiologists estimated the probability of malignancy and rated the image quality and confidence level. Performance was evaluated by sensitivity, specificity, positive predictive value, negative predictive value, and receiver operating characteristic (ROC) analysis.II. Comparison of x 2.0 zooming method (ZOOM-2.0) with MAG in FFDM: image quality and diagnostic performance for microcalcificationsThree radiologists with different levels of experience in mammography reviewed each FFDM reader set for 185 patients with pathologically-proven microcalcification clusters, which consisted of MAG with a magnification factor of 1.8 and ZOOM with a zoom factor of 2.0. Each radiologist rated their suspicion of breast cancer in microcalcific lesions using a 6-point scale and used a 5-point scale to rate image quality and confidence level in their decisions. Results were analyzed according to display methods using areas under the ROC curves (Az value) for ZOOM and MAG to interpret microcalcifications. DBM MRMC and Wilcoxon matched-pairs signed rank test were used for statistical analysis.RESULTS:I. All three radiologists rated MAG images higher than ZOOM-1.3 images for sensitivity (average value, 92% vs. 87%, P<0.05) and performance by ROC analysis improved with MAG imaging. The confidence level of diagnosis decision and the assessment of lesion characteristics were also better in MAG images than those in ZOOM images with statistical significance (P<0.0001).II. Az value for ZOOM-2.0 were 0.8680 and were similar to that of MAG (0.8682, 95% confidence interval for a mean difference (CI): -0.02973 to 0.02934; p=0.9897). However, MAG images were significantly better than ZOOM images in terms of visual imaging quality (p<0.001), and the confidence level with MAG was better than ZOOM (p<0.001).CONCLUSIONS:I. MAG can enhance diagnostic performance when characterizing microcalcifications. ZOOM-1.3 cannot serve as an alternative to MAG.II. Radiologist performance in the diagnosis of microcalcifications using ZOOM -2.0 was comparable to MAG. Thus, ZOOM-2.0 might be an alternative tool for MAG in the diagnosis of microcalcifications although image quality and confidence levels were not as good as MAG.

Obesity Related Metabolomic Analysis of Human Subjects in Black Soybean Peptide Intervention Study by UPLC-Q-TOF-MS : UPLC-Q-TOF-MS을 이용한 검정콩 펩타이드의 비만관련 휴먼 대사체 연구

Min Jung Kim 용인대학교 대학원 2015 국내박사

Investigation of germ cell-specific transcription systems and regulatory factors

Kim, Min-jung UMI Dissertation Services 2008 국내박사

Synthesis of Holey-polybenzimidazole (HPBI)

Min Jung Kim Grapduate School of UNIST 2014 국내석사

After Nobel Prize winning discovery of graphene in physics in 2004, two-dimensional structure grew rapidly due to outstanding thermal, physical, and electronic properties. Especially, two-dimensional nanoporous crystalline polymers (2D NPC) were concentrated due to their interesting robust structure, flexibility, and high surface area. Zeolite and metal organic frameworks (MOFs) as typical NPC have been studied showing huge potential in gas storage, catalyst, and electronic devices. However, the metallic source causes a drop of efficiency and durability as well as high cost. Hence, covalent organic frameworks (COFs) composed of organic component came to the forefront again. Most pristine 2D COFs synthesized so far with sp3 bond are sensitive to moisture and high temperature. Therefore, we synthesized holey-polybenzimidazole (HPBI) which is well-matched with theoretical structure via condensation reaction using two types of amino benzenes as monomer. Based on the hole size, they show different surface properties and band gap.

The Electron Charge Asymmetry in pp → W(eν)+X production at √s = 8 TeV at LHC

Kim, Jung-Min 강원대학교 대학원 2014 국내석사

The measurement of the electron charge asymmetry in inclusive W production with the CMS detector is presented. The electron charge asymmetry is measured with an integrated luminosity of 19.619 fb^(-1) of data collected by the CMS detector. The electron charge asymmetry is measured in eleven bins of the absolute value of electron pseudo-rapidity and compared with theory predictions. 본 논문에서는 LHC 의 8 TeV 양성자-양성자 충돌실험에서 W boson + X 데이터의 W boson의 전하 비대칭을 측정하였다. 이 연구를 통해 W plus boson과 W minus boson의 비율을 측정함으로써 u 쿼크와 d 쿼크의 비율이 8TeV 양성자-양성자 충돌에서 어떻게 생성되는지 알게되었고, 이는 앞으로 만들어질 Monte Carlo generate 단계에 적용되어 W boson에 대한 이해를 높일 수 있다. 데이터분석에는 CMSSW_5_3_9, Root, CRAB 이 사용되었다. 이벤트 데이터 분석코드는 C 언어로, 히스토그램 생성코드는 Python 언어로 작성되었다. Pseudo rapidity를 11개의 구간으로 나누어 Fitting한 결과에서 Monte Carlo(MC) shape이 real data(RD)에 잘 일치함을 보여주었다. 그리고 Fitting 결과로부터 electron charge asymmetry를 측정한 결과 MC와 RD의 값이 최소 0.3% 에서 최대 9.4% 의 오차로 일치함을 볼 수 있었다.