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.

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.

만선신부전 환자에서 관상동맥조영술 소견에 관한 연구

한대희,김성구,박상호,김성한,조원영,방덕원,조윤행,정의룡,은영근,권영구 순천향의학연구소 2003 Journal of Soonchunhyang Medical Science Vol.9 No.1

Background : Patients with chronic renal fialure have a substantially elevated risk of death from cardiovascular diseases than do the general population. the patients with chronic renal failure are at significantly increased freqeuncy of hypertension, hyperlipidemia, and diabetes mellitus which are known to the risk factors of the coronary artery diseases, and the prevalence of the coronary artery diseases in chronic renal failure patients is highly associated with the hemodynamic disorder and metabolic abnormalities. therefore we expected that the coronary angiographic findings in patients with chronic renal failure should be different from the general population (control groups) and investigated the risk factors contributing to coronary artery diseases. Method : we have retrospectively compared the coronary angiographic findings of 44 patients with chronic renal failure on hemodialysis with that of 88 patients in the general population and investigated the factors contributing to the development and acceleration of coronary artery diseases in patients with chronic renal failure Result : Hypertension and diabetes mellitus which is risk factors for coronary artery disease is significantly increased in patients with chronic renal failure, in coronary angiographic finding the severity of the lesion is worse. the incidence of PCI or CABG of patients with chronic renal failure is more than that of control group but statistically no difference between patients with chronic renal failure and control group. the sex, the duration of disease, the duration of dialysis, serum creatinine in patients with chronic renal failure have no correlation to the prevalence of coronary artery disease and severity of lesion. hyperglycemic patients with chronic renal failure have high incidence of coronary artery disease and are worse in the severity of lesion Conclusions : There is significantly increased the pevalence and severity of involving multiple coronary artery diseses in hyperglycemic patients with CRF.

횡문근융해증과 급성 신부전 및 범발성 혈관내 응고장애를 동반한 열사병 1예

최대은,박수진,권오경,이한규,이영모,이상주,나기량,이강욱,신영태 충남대학교 의학연구소 2003 충남의대잡지 Vol.30 No.2

Heat stroke is a life-threatening illness characterized by an elevated core body temperature that rises above 40% and central nervous system dysfunctions that results in delirium, convulsions, or coma. Heat stroke is subdivided into two forms, classic and exertional. Since strenuous exercise is one of the major exacerbating and precipitating factors, the incidence of exertional heat stroke is high among young adult, especially military personnel undergoing military training. Exertional heat stroke commonly causes rhabdomyolysis, lactic acidosis, acute renal failure, shock and pulmonary edema. We report a case of heat stroke with rhabdomyolysis, acute renal failure, disseminated intravascular coagulopathy(DIC) after strenuous exercise. A 18 year old man was admitted to the hospital because of loss of consciousness. He was a wrestler and he had tried to lose 6kg in weight by jogging and strenuous exercise on that summer day with hot temperature. The development of this illness was favoured by much clothes inappropriate for that environmental condition with a purpose to enhance sweating, and by restricted intake of water and food. On admission, the blood pressure was 80/50mmHg, and body temperature was 39.4℃ with stuporous mentality. Laboratory finding were as follows : in complete blood cell count, hemoglobin was 16.7g/dL and platelet count was 158,000/ mm³. In blood chemistry, AST 1061U/L, ALT 201U/L, BUN 30mg/dL, Cr 2.2mg/dL, LDH 941IU/L, CK 696IU/L were resulted. In arterial blood gas analysis, pH 7.39, pCO₂ 30mmHg pO₂ 86mmHg, HCO₃ 18.4mEq/L, O₂ saturation 96.7% were resulted. In urinalysis, specific gravity 1.025, protein 3+, erythrocyte 2+ were resulted. In brain imaging study, brain CT finding was normal. After appropriate treatments with rapid cooling, hydration and supportive care, he improved with alert mental status. On 2nd hospital day, in laboratory result, thrombocytopenia and coagulopathy were appeared and renal insufficiency was aggravated. So he was treated with platelet concentrate and fresh frosen plasma for DIC, and enough hydration for appropriate urine volume preservation. After all, On 22nd hospital day, he fully recovered and discharged. Nowadays, with followed for some duration, he is wellbeing with no complications.

地下空洞의 安定性 解析을 爲한 岩盤特性 係數間의 關係와 入力資料補正에 關한 硏究

安大榮,崔榮天 尙志大學校 1992 論文集 Vol.13 No.-

R.Q.D. and seismic velocity is known as the most reasonable data among the given datum in numercal representation of rock mass quality index. R.Q.D. represents frequency of fissures, while fissures of bedrock bring about some decrease in velocity and young modules related to rock mass. According we discuss about the relation between R.Q.D. and characteristic parameters such as Velocity, Velocity index, Joint frequency young modules and ratio. We give a conclusion that the relation is nearly given by a linear equation as follows. 1) The relation between R.Q.D(Q) and velocity(V) is showed a linear equation R=33.4(V-2.5), and its velocity index(VF/VL)2 is not always 1:1. 2) The relation between R.Q.D and modules ratio(Er/Erab) can be represented the equation Er/Erab 2 Cro 32, R.Q.D-2.22. 3) The ratio between compress strength and youn's modules can be showed the range of 1:380, and young's modules in granodiorite is given the range of 1.91 4.51. 4) The compress strength(Qc) by the means of point load index[Is(v)] can be represented the equation Qc=15.6+Is(50).