Study on the Elastic Characteristics of Living Cells using Atomic Force Microscope Indentation Technique

Eun-Young Kwon,Young-Tae Kim,Dae-Eun Kim 한국트라이볼로지학회 2006 KSTLE International Journal Vol.7 No.1

In this work, imaging and study of elastic property of the living cell was performed. The motivation of this work was to seek the possibility of exploiting Young’s modulus as a disease indicator using Atomic Force Microscope (AFM) and also to gain fundamental understanding of cell mechanics for applications in medical nanorobots of the future. L-929 fibroblast adherent cell was used as the sample. Imaging condition in cell culturing media environment was done in very low speed (20 μm/s) compared to that in the ambient environment. For measuring the Young’s modulus of the living cell, AFM indentation method was used. From the force-distance curve obtained from the indentation experiment the Young’s modulus could be derived using the Hertz model. The Young’s modulus of living L-929 fibroblast cell was 1.29 ± 0.2 kPa.

AFM indentation 기법을 이용한 세포의 탄성특성에 관한 연구

권은영(Eun-Young Kwon),김영태(Young-Tae Kim),김대은(Dae-Eun Kim) 한국트라이볼로지학회 2006 한국트라이볼로지학회 학술대회 Vol.2006 No.6

In this work, imaging and investigation of elastic property of the living cell was performed. The motivation of this work was to seek the possibility of exploiting Young's modulus as a disease indicator using Atomic Force Microscope (AFM) and also to gain fundamental understanding of cell mechanics for applications in medical nanorobots of the future. L-929 fibroblast adherent cell was used as the sample. Imaging condition in cell culturing media environment was done in very low speed(20 ㎛/s) compare to that in ambient environment. For measuring the Young's modulus of the living cell, AFM indentation method was used. From the force-distance curve obtained from the indentation experiment the Young's modulus could be derived using the Hertz model. The Young's modulus of living L-929 fibroblast cell was 1.29 ± 0.2 kPa.

Study on the Elastic Characteristics of Living Cells using Atomic Force Microscope Indentation Technique

Kwon Eun-Young,Kim Young-Tae,Kim Dae-Eun Korean Tribology Society 2006 KSTLE International Journal Vol.7 No.1

In this work, imaging and study of elastic property of the living cell was performed. The motivation of this work was to seek the possibility of exploiting Young's modulus as a disease indicator using Atomic Force Microscope (AFM) and also to gain fundamental understanding of cell mechanics for applications in medical nanorobots of the future. L-929 fibroblast adherent cell was used as the sample. Imaging condition in cell culturing media environment was done in very low speed ($20{\mu}m/ s$) compared to that in the ambient environment. For measuring the Young's modulus of the living cell, AFM indentation method was used. From the force-distance curve obtained from the indentation experiment the Young's modulus could be derived using the Hertz model. The Young's modulus of living L-929 fibroblast cell was $1.29{\pm}0.2$ kPa.

Factors associated with the risk of colorectal neoplasia in young adults under age 40

Ilsoo Kim,Han Hee Lee,Young Jae Ko,Ho Eun Chang,Dae Young Cheung,Bo-In Lee,Young-Seok Cho,Jin Il Kim,Myung-Gyu Choi 대한내과학회 2022 The Korean Journal of Internal Medicine Vol.37 No.5

Background/Aims: Recent epidemiologic studies have shown a continued increase in colorectal cancer incidence among younger adults. Little is known about the factors that contribute to the development of young-onset colorectal neoplasia (CRN). Methods: A cross-sectional analysis was performed for individuals younger than 40 years who underwent colonoscopy in Seoul St. Mary’s Hospital and its affiliated health screening center. High-risk CRN was defined as adenoma or sessile serrated lesion ≥ 10 mm, with three or more adenomas, villous histology, high grade dysplasia, or carcinoma. Results: Of these 13,621 included participants, 2,023 (14.9%) had one and more CRN. Young patients with CRN tended to be elderly, male, obese, smoker, having a habit of drinking, and having comorbidities such as hypertension, dyslipidemia, diabetes, and chronic kidney disease. In a multivariate analysis adjusted for age, sex, obesity, smoking status, and alcohol intake, old age (odds ratio [OR], 1.086; 95% confidence interval [CI], 1.054 to 1.119), male sex (OR, 1.748; 95% CI, 1.247 to 2.451), obesity (OR, 1.439; 95% CI, 1.133 to 1.828), and smoking (OR, 1.654; 95% CI, 1.287 to 2.127) were independent risk factors for overall CRN. Obesity and smoking as two modifiable factors increased the risk for high-risk CRN even more than for overall CRN (OR, 1.734; 95% CI, 1.168 to 2.575 and OR, 1.797; 95% CI, 1.172 to 2.753, respectively). Conclusions: Obesity and smoking were modifiable risk factors for CRN in young adults. They increased the risk for highrisk CRN even more than for overall CRN. A colonoscopy might be beneficial for young individuals with these factors.

Communication, Argumentation and Relevance

Dae-Young Kim 한국언어학회 2014 언어 Vol.39 No.4

Kim, Dae-Young. 2014. Communication, Argumentation and Relevance. Korean Journal of Linguistics, 39-4, 719-748. The purpose of this paper is to argue that a theory of argumentation can be incorporated into a theory of communication (i.e. Relevance Theory). Whereas argumentation is the process of justifying something in an organized or a logical way, which is composed of one or more claims and shows one or more grounds for maintaining them, communication is sharing communicators’ intentions. A speaker’s conveying of his intention to hearer is to create an effect in the hearer’s mind. Two pragmatic theories, Relevance Theory (henceforth RT) and argumentation theory (henceforth AT) are involved in this approach, which is based on the position that communication is always accompanied with argumentation. However, RT has been more focused on explaining how the utterance is interpreted by the hearer, not how argumentation is performed. For this reason, this approach presented here argues for the needs to extend the scope of RT’s application. This integrated approach within a single principle of relevance ultimately contributes to pursuing a more economic and coherent explanation of argumentation. (Jeonju University)

Effects of Humidity on the Microstructure and the Ferroelectric Properties of Sol-Gel grown P(VDF-TrFE) Films

Young Joon Ko,진다운,Dae Sol Kong,Jong Hoon Jung 한국물리학회 2020 THE JOURNAL OF THE KOREAN PHYSICAL SOCIETY Vol.76 No.4

We report the microstructure and the ferroelectric properties of poly(vinylidene fluoride-trifluoroethylene) [P(VDF-TrFE)] films grown under various humidity conditions and synthesis times by using a sol-gel method. When the synthesis time under a humid condition was short (approximately 30 min), the moisture in the environment affected only the surface morphology without any loss of ferroelectricity for the P(VDF-TrFE) films. In contrast, when the synthesis time was long (approximately 90 min), the moisture strongly affected the microstructure and the ferroelectric properties of P(VDF-TrFE). The transparent P(VDF-TrFE) film became opaque at high humidity. Scanning electron microscopy revealed numerous pores on the surface of and inside the film. The pores reduced the Young's modulus considerably from 4.15 to 0.97 GPa for the films grown at 20 and 80% relative humidity, respectively. In addition, the ferroelectric hysteresis loop disappeared at humidities above 60%. This work provides upper limits for the humidity and the synthesis time for the growth of high-quality P(VDF-TrFE) films by using a sol-gel method.

태권도 선수의 인지 재구성에 의한 시합 불안 감소 연구

박영수 ( Young Soo Park ),양대승 ( Dae Seung Yang ),서진교 ( Jin Gyo Seo ) 국기원 2010 국기원태권도연구 Vol.1 No.1

본 연구의 목적은 김용승(1996)이 개발한 심리기술 강화 훈련 프로그램(시합불안 제어용)의 단축형을 스포츠 현장의 태권도 선수 남녀 2명에게 적용하고 그의 시합불안 제어효과를 조사하고자 하는 것으로 2개의 1인 대상연구 형태로 이루어 졌다. 개입프로그램은 합리적 정서적 치료(RET) 및 합리적 인지 재구성(CRR)을 기반으로 하여 개발된 것으로, 현장에서 심리학적 전문지식이 없어도 적용이 가능하도록 127개의 진술 항목이 개발되어 포함되어 있다. 대상은 남녀 대학 태권도 선수 2명이며 평소 시합불안 제어가 필요함을 표현하던 선수였다. 연구개입은 각각 4회기에 걸쳐 이루어졌고, 개입 전후에 SCAT 검사를 하여 특성 시합불안의 변화를 조사하였다. 개입 후에는 보충면접(Back-up Interview)을 통해 1인 대상 연구의 단점을 보완하고자 하였다. 남자 P의 경우 개입 프로그램 전후의 SCAT 점수는 15점에서 14점으로 1점의 감소를 보였으나, 보충면접을 통해 개입 프로그램이 시합 불안을 낮추는데 효과가 있었다는 것이 밝혀졌다. 피험자 L의 경우도 개입 프로그램 전의 점수가 20점이었으나 프로그램 개입 후의 점수는 12점으로 대폭 감소하여 개입 프로그램이 L의 시합 불안을 급격하게 감소시킨 것으로 나타났으며, 보충면접에서도 L은 개입 프로그램으로 시합 불안이 크게 감소하였다고 진술하였다. 따라서 이 프로그램은 태권도 선수들의 시합 시 불안을 감소시킬 뿐만 아니라 훈련 시에도 개입효과를 기대할 수 있다. This study aims to apply the simple version of Mental Technique Enhancing Training Program (for controlling game anxiety) developed by Young-Seung Kim (1996) to 2 Taekwondo players (male and female) in the sports field and to research the game anxiety control effect and was composed of 2 one-person studies. The intervention program was developed based on Rational-Emotive Therapy (RET) and Cognitive, Rational Restructuring (CRR) and is composed of 127 statement items developed for this research so that it can be applied without psychological expertise in the field. The subjects were 2 college taekwondo players who needed to control game anxiety usually. The intervention was performed 4 times for each player and examined the change of game trait anxiety by SCAT test before and after the intervention. Back-up interview was conducted to compensate for the weakness of one-person study after intervention. In case of male subject P, the SCAT score decreased from 15 to 14 after the intervention but it was concluded through the back-up interview that the intervention was effective in reducing game anxiety. In case of subject L, the SCAT score sharply decreased from 20 to 12 after the intervention, showing that the intervention program reduced game anxiety drastically. The subject L also stated that the game anxiety was reduced greatly due to the intervention in the back-up interview. Thus, it was concluded that this program can not only reduce anxiety during a game for taekwondo players but also have anxiety control effect during training session.

공황장애환자에서 광장공포증 동반여부에 따른 스트레스대처방식의 차이

최은영,제영묘,이대수,정영인 대한생물치료정신의학회 2001 생물치료정신의학 Vol.7 No.1

In an attempt to know the factors affecting the development of agoraphobia following panic attacks, the author investigated whether there are differences between coping strategies of panic disorder with and without ago-raphobia. Thirty-seven patients meeting the criteria of DSM-IV panic disorder were divided into 2 subgroups, one group with agoraphobia, another without agoraphobia. Questionaires for the severity of panic symptoms, and of anticipating anxiety for panic attacks, multidimensional coping scale for stress were administered to panic subjects. The results were summarized as follows. 1) Group of panic disorder with agoraphobia complaints trembling or shaking more than group of panic disorder without agoraphobia. 2) There was no differences of degree for the severity of anticipating anxiety between two groups. 3) Group of Panic disorder with agoraphobia had higher score on BDI than Group of panic disorder without agoraphobia. 4) Group of panic disorder with agoraphobia had lower score on active coping, positive interpretation, acceptance than group of panic disorder without agoraphobia, and the differences of these strategies between two groups were not correlated with the score on BDI at the time of investigation. In conclusion, these results suggest that the coping strategies for stress may be a predictor of agoraphobia in patients with panic disorder.

대스팬 지붕구조물의 바람에 의한 동적거동을 고려한 풍하중 평가에 관한 연구

김대영,김지영,김한영,이명호,김상대 대한건축학회 2004 대한건축학회 학술발표대회 논문집 - 계획계/구조계 Vol.24 No.1(구조계)

Generally, wind loads for large span structures are evaluated with surface pressure data acquired in wind tunnel test. Unlike cladding wind loads, the structural wind loads could be over-estimated with only peak pressures of each surface pressure point because the peak pressures on a surface are not well correlated at a given time. Also, the load shapes of wind loads, and the load effects and dynamic behaviors of a structure should be considered in the wind load assessment. In this study, several wind load evaluation methods were applied to Gwangmyeong Velodrome dome and the results were compared to analyze the properties of each method for the suggestion of a proper evaluation procedure.

만성 승모판 패쇄부전증 환자에서의 안지오텐신 전환효소 억제제의 장기 투여 효과

김대희,이명묵,이해영,조현재,박승정,서재빈,서정원,양한모,윤창환,조상호,이준희,김용진,김명아,손대원,오병희,박영배 대한순환기학회 2004 Korean Circulation Journal Vol.34 No.2