Superconducting MgB2 Wire Drawing Considering Anisotropic Hardening Behavior and Hydrostatic Effect

Young‑Seok Oh,Ho Won Lee,Kook‑Chae Chung,Duck‑Young Hwang,Seong‑Hoon Kang,Jeong Whan Yoon 대한금속·재료학회 2022 METALS AND MATERIALS International Vol.28 No.7

Numerical modeling was conducted to investigate the deformation behavior of powder mixture during multi-pass drawingprocesses for multi-filamentary MgB2wire. A modified Drucker-Prager Cap (DPC) model with an elliptical cap surface usingthe new material characterization method was developed to capture the anisotropic hardening behavior and hydrostatic effectof the powder mixture. A number of uniaxial die compaction, cold isostatic pressing, diametrical compression, and uniaxialcompression tests were conducted using different powder densities to characterize the modified DPC model. A commercialfinite element software ABAQUS with a user subroutine was used to simulate the drawing of the MgB2wire. The densityand area fraction of the powder mixture during the wire-drawing process were verified with experimental results. The differencein packing density at the inner and outer filaments of the MgB2wire was successfully captured by simulation. Inaddition, the effect of the initial packing density on the superconducting properties of MgB2wire was numerically studied. It is shown that the increase in the superconducting area, which results from a high initial packing density, should be moreeffective compared to the increase in the grain connectivity in enhancing the critical current properties for the MgB2wirewhen the final packing density is saturated after a number of drawing processes.

간세포암과 감별이 어려웠던 악성중피종 치험 1예

김선문,허원석,채경훈,강윤세,정재훈,김연수,박기오,문희석,이엄석,김석현,성재규,이병석,이헌영,신경숙,조준식,송인상,강대영 충남대학교 의학연구소 2003 충남의대잡지 Vol.30 No.2

Malignant peritoneal mesothelioma is a rare neoplasm that arises from the mesothelium of a serosal cavity and is a rapidly fatal disease with a median survival of 4 to 12 months for untreated cases. Recently, we experienced a case with malignant peritoneal mesothelioma who was suspected hepatocelluar carcioma by abdominal CT scan and was confirmed by biopsy including immunohistochemical stain(calretinin) after surgery. We performed tumor excisions and wedge resection of the liver(segment Ⅷ)and inserted Tencoff catheter in abdominal cavity at 25th day of post-operation. We treated with intraperitoneal paclitaxel(25mg/m^(2)/day for 5 days) six courses monthly. She was well tolerable and is still living without any evidence of recurrence for 14th month of post-operation.

Neuropathic Pain의 동물모델에서 유발된 Thermal Hyperalgesia에 대한 Clonidine의 효과

윤석화,오세철,최세진 충남대학교 의과대학 지역사회의학연구소 1993 충남의대잡지 Vol.20 No.2

The effects of intraperitoneal injection(i.p.) of the alpha 2 adrenal receptive agonist, clonidine on the thermal hyperalgesia produced by unilateral patially tight ligation of the sciatic nerve was studied in rats. First in the preoperative and postoperative Mays, paw withdrawal latency of both hind paw(lesioned,unlesioned) with heat stimulant was tested. After that, each groups of rats injected saline, clonidine 10㎍/kg, or clonidine 50㎍/kg. I.p.10㎍/kg and 50㎍/kg clonidine, paw withdrawal latency of lesioned side significantly reduced than saline group. It is suggested systemical clonidine may be useful in treating neuropathic pain in humans.

해조류에서 추출한 SCH-T3의 elastase 억제

오경석,박영립,이종석,황규왕,염윤기 순천향의학연구소 2001 Journal of Soonchunhyang Medical Science Vol.7 No.1

Background & Objective: Upon UV irradiation of skin, matrix metalloproteinases are induced and then degrade collagen and elastin which provide the structural integrity of skin. The purpose of this study is to investigate the inhibition of elastase by SCH-T3 extracted from marine plants. Method: From gathered seaweeds, which are Laminariacea and Alariaceae in Phaeophyta, In Korea water, 21 materials were extracted. To determine the optimal condition for the extraction of SCH-T3, the yields of SCH-T3 was measured compared at various solvents, concentrations, and extraction time. Finally, the inhibitory effect of SCH-T3 on elastase was measured under various conentrations of SCH-T3. Results: Among 21 extracts, SCH-T3 had excellent elastase inhibitory effect. The yields of SCH-T3 was highest with the use of 60% and 70% ethanol as sovents, at 12 hours extraction, and with increasing temperature. Conclusion: These results suggest that SCH-T3, extracted from marine plants, has an inhibitory effect on elastase in vitro and may be used in prevention and treatment of photoaging in the future.

HPLC-MS/MS를 이용하여 혈장 중 레보티인정의 정량분석

채석,오형근,이상선,김형기,손동렬,염윤기,맹주양,권준택 순천향의학연구소 2008 Journal of Soonchunhyang Medical Science Vol.14 No.2

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하악골 골절 환자에 있어 수술후 합병증으로 발생한 골수염의 치험례

윤규호,전인성,신용길,박준호,허남오,방석준 大韓顎顔面成形再建外科學會 1996 Maxillofacial Plastic Reconstructive Surgery Vol.18 No.4

The term osteomyelitis literally means inflammation of bone marrow. It is described as an inflammatory condition of bone primarily engaging the medullary Following circulatory collapse and ischemia, the involved portions of the bone become necrotic. Cellulitis and osteomyelitis are the most frequent complications of fractures of the mandible and maxilla, because there is an abscessed tooth in the line of fracture. Since most fractures are compound fractures, infection may develop because of contact with oral secretions or outside air. The treatment of chronic osteomyelitis is still under debate. Some authors rely on antibiotics alone, while others advocate combination with surgery. But when infection occurs, establish proper drainage and administer antibiotics. Author treated a case of infected mandibular fracture with mandibular osteotomy, sequestrectomy, iliac bone graft and hyperbaric oxygen therapy, who had suffered suppurative osteomyelitis and mandibular nonunion following the open reduction of the mandibular fracture.

자가 면역성 간염에서 자가항체의 발현 양상과 스테로이드 치료의 효과

박기오,채경훈,허원석,강윤세,정재훈,김연수,문희석,이엄석,김선문,이병석,김남재,이헌영 충남대학교 의과대학 의학연구소 2003 충남의대잡지 Vol.30 No.1

목적 : 최근 8년간 본원에서 경험한 자기면역성 간염의 혈액학적 특징과 스테로이드의 치료효과를 알아보고자 본 연구를 시행하였다. 방법 : 1996년 이후부터 2002년까지 충남대학교 병원에서 1999년 International Autoimmune Hepatitis Group(LAHG)에서 제시한 수정 진단 기준안에 의거하여 총 진단점수가 probable 이상에 해당하는 환자들을 대상으로 임상적 특징, 검사실 및 조직 소견과 스테로이드와 azathioprine의 치료 효과를 후향적으로 조사하였다. 결과 : 9예의 환자들은 여성이 78%, 40대가 많았고, 급성 발병이 33.3%, 피로감, 식욕부진 및 황달 등이 나타났으며, 항핵항체가 55.6%에서 그리고 항평활근 항체가 77.8%에서 양성이었고, 동반 질환은 류마치스 관절염이 2예, 특발성 혈소판 감소증 1예, Henoch-Sch nlein 자반증 및 그레브스병이 각각 1예 씩이었다. 7예에 대해서 스테로이드와 azathioprine으로 치료하여 생화학적 임상적 완해가 이루어져서 유효한 치료 결과를 얻었다. 결론 : 자가면역성 간염은 우리 나라에서 원인을 찾을 수 없는 만성 간질환의 경우, 특히 중년여성에서 다른 자가면역성 질환이 동반되었을 때 자가면역성 간염을 의심하여 자가항체 선별검사를 시행해 보아야 할 것으로 생각된다. 향후 다기관 연구를 통하여 좀 더 많은 증례를 모으고 전향적인 연구를 시행하여야 할 필요가 있다. Although autoimmune hepatitis(AIH) is common in western contries, some studties have been reported in Korea. The aim of the study was to analyze the clinical and histological features and expression pattern of the autoantibody and to examine clinical course of AIH in Korea. For 9 patients diagnosed as having AIH in our hospital since 1996, we reviewed medical records and analyzed clinical and laboratory findings retrospectively. They had a probable or definite AIH according to the revised criteria of International AIH group. The mean age was 42.7(21∼68)years and 7(77.8%) were female. Three of them(33.3%) showed acute hepatitis and five of them showed cirrhosis. Fatigue and anorexia were the most frequently complained symptoms(55.6%). Four patients(44.4%) were accompanied with other autoimmune diseases. Antinuclear antibody was detected in 5(55.6%) and anti-smooth muscle antibody was detected in 7(77.8%). Three patients showed focal picemeal necrosis and four showed periportal fibrosis. Among 7 patients who received immunosuppressive therapy, six patients(85.7%) showed initial response. and biochemical and serologic remission were achived in 5(71.4%) and 3(42.8%) patients, AIH seems to be partly responsible for chronic liver disease of unknown etiology in Korea. AIH should be suspected in female patients with unknown chronic liver disease of unknown etiolgy, especially accompanied with other autoimmune disease. The clinical characteristics of AIH may not be quite different from those of Western countries.

독성물질의 세포사 기전 및 세포사 유발물질의 검색법 개발에 관한 연구(Ⅰ) : 독성물질로 인한 파킨슨병 모델에서의 세포사 기전 연구 Study on the cell-death mechanisms of toxin-induced parkinsonism

강태석,김종민,서경원,김영옥,김준규,오재호,이윤동,김규봉,오정자,송연정,임종준,전범석,문전옥,최광식 식품의약품안전청 2000 식품의약품안전청 연보 Vol.4 No.-

MPTP 독성물질이 도파민성 신경세포에 선택적으로 작용하여 산화성 손상에 의한 신경세포사를 일으키는 것을 이용하여 파킨슨병의 동물모델을 만들고, 이를 통해서 아폼토시스를 비롯한 포사의 기전에 대한 연구 및 너코틴의 신경세포 보호효과 여부를 판정하는 실험을 병행하고자 하였다. 파킨슨꾐의 동물모델을 MPTf 독성 물질을 이용하여 확립하였으며, MPTP(30mgag, i.p.)를 투여한 후 1, 2,3, 4, 5일째 흑질 조직을 채춰하여 tarm로 박걸하여 tyrosine hydroxylase 면역조직화학염색을 수행하여 cell countif우한 결과, control은 57.635ce11s, 1일째 친.OfDells,2일째 57.9±6cells,3일릴 없.3±죠ells, 4일째 49.0츠3cells, 5일째 39.4±Scells료 4, 3일째 뚜렷한 신경세포 수의 감소를 보였다. 신경세포사 기전 규명을 위한 아폼토시스 분걱에서는 벼PTP 투여 후 1, 2, 3, 4, 5일째 조직을 채취하여 Hoechst staining, TUNEL staining을 수곡하였는데 양성 반응을 보인 신경세포는 관찰되지 않아. 아폼토시스로 인한 세포사가 관찰되지 않았다. bIPTP 파킨슨병 동물모델에서 nicotine 보호효과 탐색에 관한 실험은 nicat푸e 0.2mgAg을 5일 퐁안 투여 후 리『fP(30mgag)를 CS7Bt/6 마은스에 복강 내주사로 nicotine과 병용 투여한 후 1, 2, 3, 4, 5일째 뇌를 적출하땄다. 신경세포사가 뚜렷이 관찰되기 시작하는 4, 5일째의 신경세포 수의 감소 정도를 20. 30% 정도 약화시키는 경향을 보였으나, nicotine 보호효과에 대한 추가 실헝이 현재 수행 중에 있다. The cause of Parkinson's disease (PD) is largely unknown. However, free radical toxicit? may plaf a role ip. the degeneration of substantia nigra, which is the Hajorfocus of pathological damages in PD. Recently, a neuroprotective effect of nicotine in PD has been suggested. Therefore, the mechanism of neurodegenerafion and protective potential o( nicotine in PD were investigated in the experimental modeB of Pll using a neurotoxin, C57BL/6mice were administered with 1-methyl-4-phenyl-1,2,3,6-tetrahydropyridine (MPTP, 30 mg/kg,j.p.). The degree of neurodegenerafion was determined by immunohistochemical stainiHB oftyrosine hydroxylase (TH). TH-positive cells on nigral sections were found 56.0 ±4, 57.9 ±6,52.315ce11s, 49.0±3cells, and 39,4±Scells at days 1, 2, 3, 4, 5, respectively (controls : 57.6±Scells). Hoechst and TUNEL staining showed no evidence of apoptosis. The exandnation on themice co-adrunistered with nicotine(0.2mgAg) and MPTP(30mgag) revealed a tendency ofnicotine protective effects. At days 4 and 5, the degree of TH-positive cells was decreased by20-30%, In corclusiffn, the role of apoptosis was not evidenced in this MPTP modeB of PB.The possible proteccon by nicotine should be elucidated with further studies.

핸드스프링 몸펴 앞공중1회 비틀기 동작의 소요시간 및 각운동량 분석

권오석,윤양진,서국웅 한국운동역학회 2002 한국운동역학회지 Vol.12 No.2

남자 기계체조 국가대표 선수 3명과 대학선수 3명을 대상으로 핸드스프링 몸펴 앞공중1회 비틀기 동작을 구간 및 국면별로 분석하고 동작의 숙련도에 따라 역학적 변인이 집단 간 어떠한 차이를 보이는지를 구명하기 위하여 Kwon3D 프로그램을 활용하여 분석한 결과 다음과 같은 결론을 얻었다. 시간요인에서 보폭을 크게 딛는 것이 손을 빠르게 지지 할 수 있고, 핸드스프링 체공시간은 짧게 하여야 발구르기의 압력을 높여 비틀기동작에서 체공 소요 시간이 길어지므로 비틀기 수행의 완성도를 높일 수 있는 것으로 나타났다. 각운동량 요인에서 기술수행 시 전체적으로 좌우(X)축에 대한 각운동량이 전후(Y)축과 수직(Z)축에 대한 각운동량에 비해 더 큰 값을 보였다. 좌우 축 각운동량은 지면에서 이지되어 동작을 수행하는 핸드스프링회전과 앞공중1회 비틀기에서 숙련자가 상대적으로 더 큰 각운동량 보이는 것으로 나타났다. The purpose of this study were a two-fold: ⑴ to analyze event and phase of handspring salto forward stretched with turn; ⑵ to know the differences in the kinematic variables between two groups. A Kwon3D program served for the estimation of this study. The group was divided into three National representative and three well-trained calisthenics in this study. The results of this study revealed that ⑴ the forward somersault performance was increased when duration time in the air was long during the salto forward stretched that the duration time of Handspring is short, the pressure at takeoff is high, the stride is large, and hands are supporting on the ground quickly; ⑵ comparing the angular movement of anterior and posterior y axis and vertical z axis, the angular movement of right and left x axis was higher during the performance. As a result, the national representative players showed better performance in Handspring salto forward stretched with turn.

핸드스프링 무릎굽혀 앞공중돌기동작과 몸펴 앞공중돌기동작의 운동학적 비교분석

권오석,윤양진 부산대학교 사범대학 2002 교사교육연구 Vol.41 No.-

In this study, 4 gymnasts who were students of B University at that time were taken and their performance of handspring salto forward tucked and handspring salto forward stretched at through 3 dimensional movement analysis to tell the duration for each phase of the movement, the movement of the articulation of the body, the tract of moving center of the body, and its kinematic element. It is all to provide basic data for efficient training of gymnasts and the findings are as follows: 1. The time duration for phase 1 and 2 differed each other and faster landing on hands in forward handspring salto forward stretched than in forward salto with the body bent helped the straight-line movement change to circular movement giving the handspring a big circular movement, and forward jumping on feet with rapid upright of the upper body maximized the circular radius on the axis of the jaw, contributing to rapid backward circular movement of the lower part of the body. 2. In the observation of the position of the body center, the sway of the body center and the power dispersion was smaller in general in forward salto with the body stretched than in forward salto with the body bent. And in its forward and backward position, it showed lower position in handspring phase of 1 and 2, but higher in the salto of phase 3, 4 and all these contributed to bigger and more stable circular motion. 3. Articulation angle of the body in each phase of handspring forward salto with the body bent and in forward salto with the body stretched appeared to be different through 5 phases. It had more centripetal force in forward salto with the Elbows, shoulders, hips, knees having more curve. In forward salto with the body stretched, centrifugal force appeared to be strong with the elbows, shoulders, hips, knees all being extended. To summarize, Handspring forward salto with the body bent seems to have curved articulation and be slow, while in forward salto with the body stretched, its circular movement appeared be faster with speedy landing on hands, extended knees angle for good jump, and with accelerated hips articulation. Handspring forward salto with the body stretched appeared to enhance its technical performance with far-reaching circular motion. Therefore, forward salto with the body stretched is considered to produce more gracious and dynamic motion than forward salto with the body bent does.