Effect of Mn and C on Age Hardening of Fe–Mn–Al–C Lightweight Steels

Sung‑Won Park,Jun Young Park,Kyong Mox Cho,Jae Hoon Jang,Seong‑Jun Park,Joonoh Moon,Tae‑Ho Lee,Jong‑Ho Shin 대한금속·재료학회 2019 METALS AND MATERIALS International Vol.25 No.3

The effects of Mn and C content on the age hardening of Fe–Mn–Al–C lightweight steels, which have austenitic or duplex(austenite and ferrite) microstructures, were investigated. An increase in Mn content induced a delay of the age hardeningthat is caused by the formation of intra-granular κ-carbides. In order to interpret the effect of Mn content, first-principlescalculations were conducted using the supercells of Fe24Al8C8,Fe24Al8C7,Fe24(Al7Mn)C8, and Fe24(Al7Mn)C7. The calculationsshowed that an increase in Mn content could be the source of the delay of the intra-granular κ-carbide formation bysuppressing C atom’ occupation of the vacancy at the body-centered site of L12. An increase in C content accelerated theformation of intra-granular κ-carbides, which induced the intense age hardening, and coarse inter-granular κ-carbides, whichresulted in significant decrease in impact absorbed energy due to inter-granular fracture.

야뇨증 환아들의 심리사회적 특성에 대한 다기관 연구 : 행동 및 정서 문제를 중심으로

조수철,김재원,신민섭,황준원,한상원,박관현,이상돈,김경도,김건석,서홍진,이유식,정재용,김영균,문두건,남궁미경,한창희,조원열,김영식,배기수,이종국,정우영,신의진 大韓神經精神醫學會 2005 신경정신의학 Vol.44 No.6

Objectives : The aim of this study was to examine the behavioral and emotional problems associated with nocturnal enuresis in Korean children. Methods : Three hundred eighteen children with nocturnal enuresis, together with their parents, completed the Child Behavior Checklist (CBCL), Disruptive Behavior Disorder Scale according to DSM-IV (DBDS), Children's Depression Inventory (CDI), State-Trait Anxiety Inventory for Children (STAIC), and Piers-Harris Children's Self-Concept Scale (PHCSC). Ninety-three normal students were selected as the control group. Results : Compared to the normal control group, the mean scores with regard to the withdrawn, social problems, attention problems, delinquent behavior, aggressive behavior, externalizing problems and total problems profiles were significantly higher in the nocturnal enuresis group according to the CBCL results. The nocturnal enuresis group also scored significantly higher in the ADHD and ODD profiles of the DBDS. The nocturnal enuresis group was more depressed and anxious than the control group according to the results of the CDI and STAI. The mean score of the PHCSC was significantly lower in the nocturnal enuresis group when compared to the normal control group. Conclusion : The results of this study suggest that children with nocturnal enuresis in Korea have clinically relevant behavioral and emotional problems. The findings support the link between nocturnal enuresis and psychopathology in Korean children.

The Role of Skeletal Muscle Mass in Development of Metabolic Syndrome

( Byung Sam Park ),( Jun Sung Moon ),( Ji Sung Yoon ),( Kyu Chang Won ),( Hyoung Woo Lee ) 대한내과학회 2013 대한내과학회 추계학술발표논문집 Vol.2013 No.1

Introduction: It has been well known that abdominal adiposity is related with insulin resistance and greater risk of metabolic disorder. Skeletal muscle plays central role in insulin mediated glucose disposal of whole body, but we only know a little about the association between skeletal muscle mass and MetS (MetS). The aim of this study is to clarify the clinical role of skeletal muscle mass in developing MetS through using skeletal muscle parameters by body impedance analysis (BIA). Methods: 1,042 healthy adults aged from 20 to 75 years who visited Yeungnam university health promotion center from Jun. 2008 to Jun. 2010 were enrolled. 204 subjects who had prior MetS or chronic disease that can affect to skeletal muscle mass were excluded. After 24 months from baseline, the metabolic parameters were assessed and the development of MetS was diagnosed using modified NCEP-ATP III criteria. From the BIA (Inbody 720), we obtained skeletal muscle mass (SMM, Kg), body fat mass (BFM, Kg), and visceral fat area (VFA, cm2). Then, we had defined as follows; percent of skeletal muscle mass (SMM%, %): SMM (kg)/weight (Kg), skeletal muscle index (SMI, Kg/m2): SMM (Kg)/height (m)2, skeletal muscle to body fat ratio (MFR): SMM (kg)/BFM (Kg) and skeletal muscle to visceral fat ratio (SVR, Kg/cm2): SMM (Kg)/VFA (cm2) Results: Mean follow up periods were 28.7±5.4 months. Among total 838 subjects (46.9±9.9 years, M:F=477:361), 88 (10.5%) were newly diagnosed MetS. 5th quintile of the SMM%, MFR and SVR was associated with decreased risk of development of MetS after adjusting for confounding factors. Conclusion: Decreased skeletal muscle mass may play critical role in development of the MetS and not absolute amount of skeletal muscle mass but relative ratio to body composition may be more important.

흉골 골절의 의의에 관한 임상적 연구

원형섭,황성연,박정배,이준형,박철완,이근 대한응급의학회 1996 대한응급의학회지 Vol.7 No.2

It has been known that sternal fracture increases the risk of potentially life-threatening injuries, such as myocardial, pulmonary, and thoracic vascular injuries, and it has 25% to 45% of mortality, primarily resulting from these underlying injuries. The authors reviewed retrospectively the medical records and radiographic findings of the patients who admitted with sternal fracture at Chung Ang Gil Hospital from 1 June 1994 to 31 December 1995 to evaluate the significance and clinical course of sternal fracture. The results were followings: 1. The male to female ratio was 3:2 and the mean age was 43.1 and 45.4 years old in male and female, respectively. 2. Motor vehicle occupant accident was the most common cause of sternal fracture. 3. Of 33 cases, there was no death, but common associated injuries which were rib fracture, hemothorax, lung contusion, vertebral fracture, penumothorax, long bone fracture, myocardial contusion, flail chest, facial chest, facial bone fracture, and pericardial effusion, in order. 4. The clinical course of sternal fracture was determined primarily by associated injuries except for communited sternal fracture. 5. The patients with isolated sternal fracture, who had an otherwise normal chest x-ray, normal electrocardiogram, no other significant associated injuries and are hemodynamically stable, had a benign clinical course.

의료영상저장 전송시스템과 측두골 3차원 영상합성을 이용한 중이 수술에서의 임상적 유용성

전범조,여상원 최신의학사 2004 最新醫學 Vol.47 No.1

제 1형 신경섬유종증 환자에서 발생한 위장관 간질종양 1예

원경준,이준,변유미,조민근,한경택,김원,홍란,임성철,김경종,김영대,박찬국,김만우 朝鮮大學校 附設 醫學硏究所 2007 The Medical Journal of Chosun University Vol.32 No.2

Gastrointestinal stromal tumor (GIST) is the most common non-epithelial neoplasm arising in the gastrointestinal tract, but this tumor is rarely seen in association with type l neurofibromatosis (NFl) Generally, the majority of GISTs are isolated neoplasm and they are sporadically found in the stomach, but the GISTs in NFl patients are usually multiple and usually found in the small intestine. We report a case of multiple GISTs in the jejunum of a 63-year-old woman diagnosed as NFl accompanied by complication of gastrointestinal bleeding, In this case, Patient had multiple cafe-au lait spots and neurofibroma on skin and had freckling on axilla and groin, and then, we made a diagnosis of NFl. Gastrointestinal bleeding is controlled by resection of multiple GISTs. Generally, only 3-5% of all gastrointestinal bleeding comes from the small bowel. Causes of small intestinal bleeding are angiodysplasia, neoplasm, NSAIDs induced ulcer etc. but, If patients have NFl accompanied by complication of gastrointestinal bleeding, GISTs on small bowel must be considered.

소뇌뇌교각종양에서 수술중 전기생리학적 신경계집중감시의 변화

서대원,박관,안재영,이상구,정진상,홍승봉,이원용,김병준,김종현 대한신경과학회 1999 대한신경과학회지 Vol.17 No.1

운동부하양식에 따른 심폐 능력의 비교분석

전태원,우재홍,신창호,이기봉,이광희,박익렬,박성태,강현주 서울대학교 체육연구소 2000 서울大學校 體育硏究所論集 Vol.21 No.1

The purpose of this study this study was to comparative analysis the V02max and HR through arm ergometer exercise, bicycle ergometer exercise, and treadmill exercise and to propose correct data of aerobic ability according to GXT. Subjects for study were 8 healthy male students. The process of the test were performed maximal GXT on arm ergometer exercise, bicycle ergometer exercise, and treadmill exercise and measured V02max, max heart rate and recovery time of 3 VO2 and heart rate respectively. The conclusions were supported by the findings of this study: 1.There were significant differences between test style and V02/kg/min(p<.05). 2.There were significant differences between test style and test stage at heart rate(p<.05) There were no effect of reciprocal action. Therefore, V02/kg/min should be on individual exercise prescription guiedlines for health promotion should be provided proper GXT which are arm ergometer exercise, bicycle ergometer exercise, and treadmill exercise.

동통성 안근마비를 나타낸 양측성 자발성 경동맥해면정맥동루 2례

전성만,박경원,차재관,김상호,김재우,최순섭 대한신경과학회 1997 대한신경과학회지 Vol.15 No.5

허혈성 심질환에서 나타나는 항산화지수, 사이토카인 및 염증지표의 변화

전상훔,안지훈,방덕원,온영근,현민수,김성구,권영주 순천향대학교 교수학습개발센터 2004 Journal of Soonchunhyang Medical Science Vol.10 No.3

Purpose : As diet habits change and the elderly popuation increases conronary artery disease(CAD) has also increased. Recent ongoing studies on varous inflammatory indexes in acute coronary syndrome(ACS) are underway. Several study results have shown that total antioxidant status(TAS) was remarkably lower in unstable angina than in chronic stable angina and levels of interleukin-(IL-6), C-reactive protein(CRP), monocyte chemoattractant protein-1(MCP-1), P-selectin were reported to be elevated in unstable angina and acute myocardial infarction(AMI). In our study, we studied and compared the level changes of cytokines and inflammatory indexes that play important roles inside the blood vessel. Methods : Study subjects were patients who were admitted and underwent coronary angiography at the cardiology department in Soonchunhyang university hospital. Subjects were divided into 4 groups, a control group, a stable angina and unstable angina group and an acute myocardial infarction group. The clinical findings, TAS, inflammatory cytokines(P-selectin, MCP-1, IL-6), anti-inflammatory cytokines(IL-10), Homocysteine and CRP levels in each group were measured and compared. Results : The total number of study participants was 86 patients, with 26 patients in the control group, 21 patients with stable angina, 15 patients with unstable angina, and 24 patients with AMI. There were significant differences in the TAS among the 4 grouops. 1.7±0.51 mmol/L, 1.6±0.60 mmol/L, 1.4±0.20 mmol/L, 1.4±0.29 mmol/L respectively. IL-6 levels also showed a significant difference between groups, averaging 0.8±2.47 pg/ml, 2.7±3.77 pg/ml, 6.8±10.63 pg/ml, 10.9±17.43 pg/ml respectively. Homocysteine levels averaged 8.0±2.47 pg/ml, 6.8±10.63 pg/ml, 10.9±17.43 pg/ml restectively. Homocysteine levels averaged 8.0±1.0 μmol/L in the control group, 14.3±5.14 μmol/L in patients with stable angina, 16.0±4.66 μmol/L in patients with unstable angina, and 17.3±10.08 μmol/L in AMI patients. Conclusion : Compared to the control group, the TAS levels were significantly lower in patients with unstable angina and AMI. there was no difference between the control group and those with stable angina. IL-6 and homocysteine levels were also higher in patients with unstable angina and AMI. Therefore we concluded that measurements of TAS, IL-6 and homocysteine are useful in measuring the inflammatory index of coronary artery diseases and may be important factors in predicting the states and prognosis of cardiovascular disorders.