Microstructure and High Temperature Mechanical Property of Fe–Cr–B Based Metal/Ceramic Composite Manufactured by Metal Injection Molding Process

Kee‑Ahn Lee,Jin‑Han Gwon,윤태식 대한금속·재료학회 2018 METALS AND MATERIALS International Vol.24 No.2

This study investigated the microstructure and the room and high temperature mechanical properties of Fe–Cr–B alloy manufacturedby metal injection molding. In addition, hot isostatic pressing was performed to increase the density of the material,and a comparison of properties was made. Microstructural observation confirmed a bi-continuous structure composedof a three-dimensional network of α-Fe phase and (Cr,Fe)2B phase. The HIPed specimen featured a well-formed adhesionbetween the α-Fe phase and boride, and the number of fine pores was significantly reduced. The tensile results confirmed thatthe HIPed specimen (RT to 900 °C) had higher strengths compared to the as-sintered specimen, and the change of elongationstarting from 700 °C was significantly greater in the HIPed specimen. Fractography suggested that cracks propagatedmostly along the interface between the α-Fe matrix and boride in the as-sintered specimen, while direct fracture of boridewas observed in addition to interface separation in the HIPed specimen.

한국산 바질(Ocimum basilicum L.)의 휘발성 성분

이재곤,안대진,곽재진,장희진,정기택,이종철 한국식품영양학회 1999 韓國食品營養學會誌 Vol.12 No.5

동시증류추출장치를 사용하여 분리한 Sweet계 바질(Ocimum basilicum)의 4개 품종(anise, darkopal, lettuce, sweet)의 휘발성 성분을 GC/MSD로 확인하였다 확인된 성분을 기능기별로 분류하면 alcohol 성분들이 11종, carbonyl 화합물이 6종, terpene 관련 화합물이 19종. ester 화합물이 5종으로 나타났다. 주요 화합물들은 1,8-cineole(2.86∼5.04%), camphor(1.07∼l.87%), α-Bergamotene(2.05∼5.40%), methyl chavicol(0∼25.49%), eugenol (3.55∼13.53%) 등의 carbonyl 화합물과 linalool(28.52∼36.50%), bornyl acetate(0.48∼2.79%), methyl cinnamate(0∼23.12%)등의 alcohol과 ester류, cis-ocimene(1.15∼2.02%), β -cubebene(2.77∼4.80%), cadinene(1.08∼1.70%)등의 terpene 화합물이 주요 성분으로 확인되었다. Darkopal, lettuce, sweet 바질은 linalool(30.09∼35.50%), methyl chavicol(8.09∼25.49%)이 주요 성분으로 나타났고, Anise 바질은 linalool(28.52%), methyl cinnamate(23.12%)가 주요 성분으로 확인되었으나 바질의 주요성분으로 알려져 있는 methyl chavicol은 검출되지 않았다. The essential oils of anise, darkopal, lettuce and sweet basils cultivated in Korea were extracted by simultaneous steam distillation and extraction method and were analyzed by GC/MSD. Total 41 components were identified in essential oils including 11 alcohols, 6 carbonyls, 19 hydrocarbons and 5 esters components. The major components were 1,8-cineole, linalool, α-bergamotene, β-elemene, methyl chavicol, β-cubebene, methyl cinnamate and eugenol. Darkopal, lettuce and sweet basils were rich in linalool(30. 1∼36.5%), methyl chavicol(8.1∼25.5%) and relatively poor in methyl cinnamate(0∼2.71%). Anise basil was rich in linalool(28.5%) and methyl cinnamate(23.1%). However, methyl chavicol, which was known as one of the main components of basil, was not detected.

한국 정신장애의 역학 조사 연구[I] : 각 정신장애의 유병률

조맹제,함봉진,김장규,박강규,정은기,서동우,김선욱,조성진,이준영,홍진표,최용성,박종익,이동우,이기철,배재남,신정호,정인원,박종한,배안,이충경 大韓神經精神醫學會 2004 신경정신의학 Vol.43 No.4

Objectives : This study aims to estimate the prevalence of the DSM-IV psychiatric disorders in Korean population using the Korean version of Composite International Diagnostic Interview (K-CIDI). Methods : Subjects were selected by taking multi-stage, cluster samples of 7,867 adult household residents, 18 to 64 years of age, in ten catchment areas. Total 78 trained interviewers administered the K-CIDI to the selected respondents, from June 1 to November30,2001. Results : Total 6,275 respondents completed the interview. Some 33.5% of respondents reported at least one lifetime disorder, 20.6% reported at least one-year disorder, and 16.7% reported at least one-month disorder. The most common lifetime disorders were alcohol abuse/dependence (17.24%), nicotine dependence/withdrawal (11.19%), specific phobia (5.16%), and major de-pressive disorder (4.25%). The lifetime prevalence of substance abuse/dependence (0.25%) and schizophrenia (0.16%) was very low. Nicotine and alcohol use disorder showed very high male/female ratio. Mood disorder and anxiety disorder were more prevalent among female than male. Conclusion : The prevalence of psychiatric disorders was high. In comparison with other studies, remarkable differences in distributions of psychiatric disorders across the areas and times were observed.

선언식 사용자 인터페이스가 추가된 함수언어 시스템

金基哲,金鎭鳳 弘益大學校 科學技術硏究所 1991 科學技術硏究論文集 Vol.1 No.-

The two major languages widely used in the area of artificial intelligence are a functional language LISP and a logic-based language PROLOG. The former is good for list processing, and the latter is for declarative logic processing. In this paper, a PROLOG interpreter built on a LISP system is extended so that a natural language interface is developed for the processing of declarative facts, rules and queries. The intermediate PROLOG interpreter is able to process declarative descriptions easily but has low level features not suitable for user interface. So, the very high level natural language interface is a very ideal one for end-users. This system, having easy declarative interface and list processing facility, is believed to be suitable as a more general system tool in artificial intelligence environments.

인간의 혈장아포지단백 A-I에 특이성을 지닌 단일클론항체 A-I30의 light chain의 가변부위를 coding하는 cDNA의 클로님

이상한,우기민,조만희,장예진,김창세,김정경 순천향의학연구소 1997 Journal of Soonchunhyang Medical Science Vol.3 No.2

I prepared a monoclonal antibody (mAb) A-l30 to HDL apolipoprotein A-l with the ultimate goals of expressing the valuable immunodiagnostic single-chain Fv (scFv) in Escherichia coli. The binding specificity of mAb A-l30 was determined by Western blot analysis. From the hybridoma cell line secreting mAb A-l30, poly(A)+ RNA was prepared and used as a template for cDNA synthesis and cloning. The nucleotide sequence analyses revealed that the variable regions of the heavy and light chains were members of mouse heavy chain subgroup ⅡA and κ light chain subgroup Ⅱ, respectively. Comparison of the nucleotide sequences with mouse immunoglobulin genes listed in the GenBank data base showed that the cDNAs have not been previously reported.

생쥐 대장 평활근 세포에서 내향 정류성 칼륨 전류의 특성 연구

이은주,김명,정명섭,조향훈,김기훈,하현철,김준수,최석,전제열 朝鮮大學校 附設 醫學硏究所 2006 The Medical Journal of Chosun University Vol.31 No.2

Objectives: K^(+) channels play an important role in regulating cellular excitability. The aim of this study was to know whether or not inward rectifier K^(+) channel exists in colonic smooth muscle cells. Methods: Mouse colonic smooth muscle cells were isolated using collagenase, and then we recorded their membrane currents using a whole-cell patch clamp technique. Results: With 90 mM K^(+) in bath, hyperpolarization-induced inward currents from -120 mV to 20 mV with 400 ms duration at a holding potential of -10 mV showed rapid activation, inactivation and inward rectification. The inactivation showed single exponential time course. Reduction of external K^(+) to 60 mM decreased the amplitudes of the currents in whole test voltage range and shifted the reversal potential to more negative potential. The inactivation process and peak currents of hyperpolarization-induced inward currents were not affected by removing external Na^(+). External Ba^(+) blocked hyperpolarization-induced inward currents by dose-dependent manner and pure Ba^(+)-sensitive currents showed strong inward rectification. Cs^(+) also suppressed hyper- polarization-induced inward currents. Ba^(+) and Cs^(+)-induced inhibitiOn of hyperpolarization-induced inward currents was voltage-dependent, and the extent of inhibition increasing with membrane hyperpolarization. Conclusions: These results suggest that inward rectifier KU channels may exist in proximal colonic smooth muscle and may play an important role in regulating membrane potential.

대장에 발생한 샘암종에서 MUC1과 MUC2 점소 발현의 의의

이윤경,이주호,이용,심재영,박정훈,오수섭,박진실,기근홍 朝鮮大學校 附設 醫學硏究所 2004 The Medical Journal of Chosun University Vol.29 No.2

Background : Mucins possess the unique function of protecting and lubricating the epithelial surface and other important functions such as call growth, direct implication in the fetal development, the epithelial renewal and differentiation, the epithelial integrity, carcinogenesis, immune regulation, cellular adhesion and metastasis. Purpose : This study was done to provide the significance of alteration of MUC1 and MUC2 expression in colorectal adenocarcinoma, A series of 131 colorectal adenocarcinomas including 11 mucinous carcinomas were screened immunohistochemically for their expression of MUCI and MUC2, Materials and mehtods : Of 131 carcinomas, 76 (58,5%) were MUCI positive and 91 (68, 9%) were MUC2 positive, In normal colonic goblet cells, MUCl was not expressed but MUC2 was expressed in cytoplasm, Conclusion There were up-regulation of MUCI and down-regulation of MUC2 in colorectal carcinomas, The frequency of MUC2 positivity according to differentiation was statistically reliable. (p=0.0001)

혈전 발생의 위험 인자가 없는 환자에서 급성 신우신염에 의해 유발된 신정맥 혈전증 및 폐색전증

이광수,김아름,이승연,정주홍,김미정,이진수,정문현,홍기천,조순구 대한감염학회 2009 감염과 화학요법 Vol.41 No.5

Renal vein thrombosis (RVT) is not an uncommon condition amongst patients with nephrotic syndrome or malignancy. Septic pulmonary embolism (SPE) is associated with risk factors such as intravenous drug use, pelvic thrombophlebitis, and suppurative processes in the head and neck. However, acute pyelonephritis is a rare cause of RVT and SPE. Case reports on RVT and SPE due to acute pyelonephritis are rare. In most of the earlier cases, patients had underlying conditions such as diabetes mellitus, renal carcinoma, calyceal stones, and hyperhomocysteinemia. We report a case of acute pyelonephritis complicated by RVT and SPE that occurred in a patient without any predisposing risk factors for thromboembolism. RVT and SPE were diagnosed using computed tomography and ventilation/perfusion scan. The patient recovered with antibiotics and anticoagulation therapy without any surgical interventions.

담배 박각시나방 Manduca sexta의 계획된 세포죽음동안의 Proteasome의 변화

이구봉,우기민,조만희,이상한,장예진,김창세 순천향의학연구소 2000 Journal of Soonchunhyang Medical Science Vol.6 No.2

모든 진핵세포의 주요 단백질 분해요소인 proteasome은 변성되거나 상해된 불필요한 단백질을 제거할 뿐만 아니라, 세포주기를 비롯한 다양한 대사과정들의 주요 효소들을 필요 시 적절히 분해함으로써 항상성을 유지시키는 필수적인 효소로 잘 알려져 있다. 또한 proteasome은 특정 포유동물 조직의 계획된 세포죽음(programmed cell death 또는 apoptosis)와 밀접하게 관련되어 있다고 보고된 바, 본 연구에서는 담배 박각시나방(Manduca sexta)의 변태과정에서 일어나는 마디간 근육(intersegmental muscle)의 급격한 파괴과정동안의 proteasome의 변화양상을 발현 및 단백질 분해활성을 중점으로 조사하였다. 정상근육과 파괴직전의 근육으로부터 proteasome을 분석한 결과 단백질 분해활성이 최소한 6배 이상 증가하였으며, proteasome의 주요 구성성분들의 발현 변화를 각각의 항체(antibody)를 이용하여 조사한 결과 세포죽음 직전에 급격히 증가함을 보였다. 이러한 구성성분들의 발현증가가 proteasome 복합체 형성을 통해 활성의 증가를 일으키는지 조사한 결과, 세포내에서 실질적으로 단백질 분해활성을 담당한다고 여겨지는 26S proteasome(2,000 kDa)의 위치에서 커다란 활성의 변화와 구성성분의 증가를 볼 수 있었다. 따라서, 담배 박각시나방의 계획된 세포죽음 현상은 특정 호르몬의 신호에 의해 proteasome의 발현이 급격히 증가하여 26S proteasome의 복합체 형태로 세포 내 대부분의 단백질들을 분해함으로써 30시간이내 근육조직을 완전히 소멸시키는 것을 알 수 있었다. 한편, proteasome을 구성하는 특정 구성성분의 과다 발현이 세포의 단백질 분해현상에 어떠한 영향을 미치는 지 조사하기 위하여 쥐의 fibroblast cell에 26S proteasome의 ATPase 구성성분인 m56 유전자를 삽입한 후 세포의 추출물로부터 proteasome의 양과 활성의 변화를 관찰하였다. Proteasome을 초원심분리로 추출하여 관찰한 결과, 담배 박각시나방의 경우와는 달리 유전자 삽입 세포는 모든 실험에서 정상 세포와 전혀 차이를 보이지 않았다. 이 결과로부터 세포의 생명 유지에 필수적이고 매우 다양한 기능을 가진 proteasome은 40여개의 구성성분들의 발현이 매우 정교하게 조절되고 있으며, 특정 세포죽음 자극(apoptotic signal)이 왔을 때 일련의 구성 성분들의 발현과 26S proteasome 복합체 형성이 증가함으로써 그 기능을 수행하는 것을 알 수 있으며, 보다 자세한 연구는 비정상적 단백질 분해나 세포죽음을 동반하는 여러 질환들의 원인과 현상을 규명할 수 있으며, 또한 그 활성을 조절함으로써 궁극적인 치료의 방향도 제시 가능할 것으로 기대된다.

소아 대퇴골 간부 골절에 대한 조기 고수상 석고 고정술

이한용,유기원,정진영,손문익,김창기,강용구 대한골절학회 2003 대한골절학회지 Vol.16 No.1

목 적 : 소아 대퇴골 간부 골절의 여러 가지 치료 방법 중 조기 고수상 석고 고정술의 유용성을 알아보고자 시행하였다. 대상 및 방법 : 대퇴골 간부 골절로 1997년 1월부터 2000년 12월까지 보존적 방법으로 치료를 시행받았던 10세 미만의 소아 중 심각한 동반 손상이 없고, 추시 기간이 최소 12개월이었던 환아를 대상으로 하였다. 총 27명, 27예 이었으며, 조기 고수상 석고 고정군(조기군)이 12예, 견인 후 고수상 석고 고정군(견인군)이 15예 이었다. 두 군에 대하여 각각 수상 시 연령, 성별, 수상 기전 등의 기본 자료를 분석하였으며, 재원 기간, 견인 및 고수상 석고 고정 기간, 재원 기간 동안의 방사선 촬영횟수, 고수상 석고 고정 직후와 최종 추시 소견에서의 각 변형 및 하지 부동 등의 임상적 및 방사선학적 자료와 입원 기간 중의 총 진료비를 비교 분석하였다. 결 과 : 평균 연력은 조기군은 4.2세, 견인군은 5.3세 이었으며, 전체 연구 대상 중 남아가 24예로 88%를 차자하였고, 수상 기전은 교통사고가 20예(71%)로 가장 많았다. 재원 기간은 조기군이 평균 7.8일 이었으며, 견인군은 25.8일로 나타나 유의한 차이를 보였다. 수상 일로부터 석고 제거가지의 기간 즉 침상 안정기간은 각각 44.2일과 65.1일 이었다. 재원 기간 중 방사선 촬영 횟수는 조기군은 수상 직후 및 고정 후 각각 1회의 방사선 촬영을 하였으며, 견인군은 견인 및 정복의 정도를 파악하기 위하여 평균 6.9회의 방사선 검사를 시행하였다. 두 군 모두 최종 추시 때의 관절 운동 각도는 정상 범위에 속하였고, 고수상 석고 고정 직후와 최종 추시 소견 상 각 변형은 허용 범위 내에 있었으며, 하지 부동이 각 군에서 3예 씩 발생하였다. 총 입원 진료비는 견인군이 재원 기간의 증가로 인하여 약 2.4배의 비용이 더 필요하였다. 결 론 : 소아 대퇴골 간부 골절에 대한 조기 고수상 석고 고정술은 견인 후 고수상 석고 고정술과 비교하여 임상적 및 방사선학적 결과에서 유의한 차이가 없었으며, 재원 기간의 단축과 고정 기간의 감소를 통한 의료비 절감 및 환자 순응도를 높일 수 있었고, 방사선 촬영 횟수 감소로 소아 생식기에 대한 위험을 줄일 수 있었으므로 유용한 치료 방법이라고 판단되었다. Purpose : To evaluate an efficacy of immediate closed reduction and hip spica casting in pediatric patients with femoral shaft fractures. Materials and Methods : 27 cases of 27 pediatric patients who had seen treated conservatively for the femoral shaft fractures under 10 years of age were retrospectively reviewed. The cases with serious associated injuries were excluded. The hospital stay, duration of traction and hip spica cast, frequencies of plain radiographs, clinical and radiological outcomes at the final follow-up, and financial aspects were evaluated comparatively between the groups of immediate hip spica casting(12 cases) and traction-casting(15 cases). Results : The patients treated with immediate hip spica casting had a mean hospital stay of 7.8 days, compared with a mean of 25.8 days for those treated with traction and casting. The mean duration of immobilization were 44.2 days in the group of immediate hip spica casting, and 65.1 days in the group of traction and casting. The radiologic examinations were performed 2 times and 6.9 times respectively. The clinical and radiological outcomes at the final follow-up were good in both groups. Insignificant leg length discrepancies were seen in 3 cases each group. The total charges of traction and casting was 2.4 times higher than that of immediate hip spica casting. Conclusion : The immediate hip spica casting seems to be an effective method of treatment in femoral shaft fractures without serious associated injuries under 10 years of age because there are several advantages such as satisfactory result, shortened hospitalization and immobilization, reduction of total charges, and lowered the risk of radiologic exposures.