On the Strengthening Effects Affecting Tensile and Low Cycle Fatigue Properties of Low-Alloyed Seismic/Fire-Resistant Structural Steels

Jung‑Ho Sim,Tae‑Yeong Kim,Jun‑Yeon Kim,Chi‑Won Kim,Jun‑Ho Chung,Joonoh Moon,Chang‑Hoon Lee,Hyun‑Uk Hong 대한금속·재료학회 2022 METALS AND MATERIALS International Vol.28 No.2

In the present study, low carbon ferritic and bainitic steels with different contents of Mo, Ti, and Nb were designed for bothseismic and fire-resistant applications. The microstructure of steels containing 0.3 wt% Mo–0.02 wt% Nb (‘A’ hereinafter)was mainly composed of bainite. By contrast, the microstructure of steels with 0.2 wt% Mo–0.13 wt% Ti (‘B’ hereinafter)consisted of ferrite with a high density of nano-sized (Ti,Mo)-rich MX precipitates. The results showed that the bainiticmicrostructure (‘A’ steel) was quite favorable to high-temperature strength and thermal stability. The yield strength of ‘A’ steelat both room and 600 °C temperatures increased consistently with increasing thermal exposure time (600 °C/200–1000 h),since the precipitation of NbC particles occurred while maintaining bainitic ferrite platelets with a high density of dislocationsduring exposure. In the ‘B’ steel, the formation of nano-sized (Ti,Mo)-rich MX particles was effective to impededislocation movement, leading to excellent plasticity (lower yield ratio) at room temperature. However, their contributionto precipitation hardening was not so much at 600 °C, as compared to the bainitic strengthening. During low cycle fatiguetests at room temperature, the main different feature between the two steels is that the ‘A’ steel showed cyclic softeningwhile cyclic hardening was evident in the ‘B’ steel. The bainitic microstructure showed a better fatigue life due to increasedductility manifested by cyclic softening, by which dislocation cell was developed.

산후에 발병한 특발성 부갑상선 기능저하증 I 예

김정인,김상용,신병철,김경남,서영욱,이범주,김진화,배학연 朝鮮大學校 附設 醫學硏究所 2002 The Medical Journal of Chosun University Vol.27 No.2

Hypoparathyroidism is usually the result of an inadvertent surgical removal of all the parathyroid glands, In some instances, not all the tissues are removed, but the remainder undergoes vascular supply compromise secondary to the fibrotic changes in the neck after surgery, Previously, the surgery for hyperthyroidism was the most frequent cause of acquired hypoparathyroidism. Idiopathic hypoparathyroidism is a relatively rare disease that is characterized by hypocalcemia and hyperphosphatemia due to a parathyroid hormone deficiency of an unknown cause, It usually develops at a young age, and shows various clinical symptoms and signs accompanied with hypocalcemia. In addition, it is rarely associated with polyglandular autoimmune syndrome during the follow-up. Hypocalcemia and idiopathic hypoparathyroidism associated with labor and lactation are rarely reported condition previously. We here describe a case of a woman in whom the symptomatic severe hypocalcemia appeared after her delivery. We reviewed all the previously reported cases and suggest a possible physiological explanation for the association between pregnancy, lactation, and the appearance of symptomatic hypocalcemia.

정신분열병 환자에서 얼굴 영상의 작동기억 장애 : 기능자기공명영상연구

이창욱,김태석,주라형,박주미,박여진,김종진,전신수,배치운,김정진,이수정,이철,백인호 大韓神經精神醫學會 2005 신경정신의학 Vol.44 No.2

Objectives : Impaired processing of facial information is one of the broad ranges of cognitive deficits seen in patients with Schi-zophrenia. We aimed to elucidate the differences in brain activities involved in the process of facial working memory between schizophrenic patients and healthy comparison subjects. Methods : Twelve patients with schizophrenia were recruited along with twelve demographically matched healthy volunteers as a comparison group. Functional magnetic resonance imaging (fMRI) was used to assess cortical activities during the Perfor-mance of a 2-back working memory paradigm using images of neutral faces as mnemonic content. Rcsults : The patient group performed the tasks with reduced accuracy. Group analysis revealed that the left fusiform gyrus, the right superior frontal gyrus, the bilateral middle frontal gyri/insula, the left middle temporal gyrus, the precuneus, the quadrangular lobules and the vermis of cerebellum showed decreased cortical activities in the patient group. On the other hand, an increased level of activation in the lateral prefrontal cortex and the pahetal lobule was observed from the patient group, all in the right hemisphere. Conulusion : A decreased level of activity in the left fusiform gyrus among the patient group implicates inefficient processing of facial information. An increased level of activation in prefrontal and parietal neural networks from the patient group confirms earlier findings on the impaired working memory of patients with schizophrenia.

40세 이하 관상동맥 질환자에서 장기적 임상 관찰

이승욱,정명호,박종철,박형욱,조상희,김원,김계훈,이상현,강경태,조장현,김남호,김건형,안영근,조정관,박종춘,강정채 全南大醫大 2001 전남의대학술지 Vol.37 No.2

Original Article : Geographic difference of epidemiological features of HCV infection in Korea

( Kyung Ah Kim ),( Sook Hyang Jeong ),( Eun Sun Jang ),( Young Seok Kim3 ),( Youn Jae Lee ),( Eun Uk Jung ),( In Hee Kim ),( Sung Bum Cho ),( Mee Kyung Kee ),( Chun Kang ) 대한간학회 2014 Clinical and Molecular Hepatology(대한간학회지) Vol.20 No.4

Background/Aims: The prevalence of hepatitis C virus (HCV) infection in Korea exhibits significant geographic variation, with it being higher in Busan and Jeonam than in other areas. The reason for this intranational geographic difference was investigated in this study by conducting a comparative analysis of the risk factors related to HCV infection among three geographic areas: the capital (Seoul), Busan, and the province of Jeolla. Methods: In total, 990 patients with chronic HCV infection were prospectively enrolled at 5 university hospitals located in Seoul (n=374), Busan (n=264), and Jeolla (n=352). A standardized questionnaire survey on the risk factors for HCV infection was administered to these three groups of patients, and a comparative analysis of the findings was performed. Results: The analysis revealed significant regional differences in exposure to the risk factors of HCV infection. By comparison with patients in Seoul as a control group in the multivariate analysis, patients in Busan had significantly more experience of invasive medical procedures, acupuncture, cosmetic procedures, and multiple sex partners. In contrast, patients in Jeolla were significantly older, and they had a higher prevalence of hepatocellular carcinoma, a lower prevalence of multiple sex partners, and had experienced fewer invasive procedures. Conclusions: There was a significant geographic difference in the exposure to potential risk factors of HCV infection between patients from the three studied regions. This may explain the regional variation of the prevalence of HCV infection in Korea, and should be taken into account when planning strategies for the prevention and management of HCV infection. (Clin Mol Hepatol 2014;20:361-367)

그람양성구균에 대한 Teicoplanin과 Vancomycin의 시험관내 항균력

최태열,김경숙,전용관,서일혜,김정욱,이웅수,안정열,김홍석,정재용,최효선,김덕언,유진우 대한감염학회 1994 감염 Vol.26 No.1

An increasing frequency of methicillin resistant S. aureus(MRSA), methicillin resistant coagulase negative staphylococci(MRCNS) and Enterococcal infection have been observed in recent years. Teicoplanin is a new glycopeptide antibiotic obstained from the Actinoplanes teicomycetius. The molecular structure and spectrum of antimicrobial activity of teicoplanin is simillar to those of vancomycin, and has been reported to have an excellent in vitro and in vivo effect against various gram-positive infections. Therefore, we evaluated the in vitor susceptibility of gram positive cocci, such as, S. aureus, coagulase negative Staphylococci(CNS), and Enterococci to teicoplanin and vancomycin. The total 253 strains consisted of MSSA(40), MRSA(53), MSCNS(47), MRCNS(48), and Enterococci(65). They were assayed by disc diffusion and agar dilution. During the study, 57% of S. aureus and 49% of CNS showed resistance to methicillin. The inhibitory diameter of teicoplanin was 15-20mm in MSSA, 12-19mm in MRSA, 13-24mm in MSCNS, 11-23mm in MRCNS, and 15-22mm in Enterococci respectively, and showed sensitivity in all but 8 strains(3.2%). The range of the minimum inhibitory concentration (MIC) of teicoplanin to MSSA, MRSA, MSCNS, MRCNS and Enterococci were 9.12-2.0㎍/ml, 0.25-2.0㎍/ml, & 0.25-32㎍/ml, 0.12-1.0㎍/ml respectively. One case of S. haemolyticus was resistant to teicoplanin (32㎍/ml) by the agar dilution method. Eight minor (3.2%) and one major(0.4%) error was observed when the MIC and disk diffusion data were correlated with teicoplanin. As for vancomycin the inhibitory diameter was 17-21mm in MSSA, 15-21mm in MRSA, 18-26mm in MSCNS, 18-25mm in MRCNS, and 16-22mm in Enterococci respectively. The range of the MIC of vancomycin to MSSA, MRSA, MSCNS, MRCNS, and Enterococci were 0.25-1.0㎍/ml, 0.25-4.0㎍/ml, 0.5-2.0㎍/ml and 0.5-2.0㎍/ml respectively. One minor error (0.4%) was seen with the vancomycin disk. The MIC90 of MSSA and MRSA exhibited the same results in teicoplanin (1.0㎍/ml, 1.0㎍/ml), and vancomycin(2.0㎍/ml, 2.0㎍/ml). MSCNS and MRCNS exhibited greater MIC90 with teicoplanin(4.0㎍/ml, 8.0㎍/ml) than vancomycin(2.0㎍/ml, 2.0㎍/ml). Incontrase Enterococci were more susceptible to teicoplanin(0.5㎍/ml) than to vancomucin (2.0㎍/ml). Results from this analysis indicated that both teicoplanin and vancomycin were very excellent for gram positive infections, especially those resistant to methicillin.

내시경적 점막절제술로 치험한 식도 과립상 세포종 1례

강혁주,김성욱,최석진,이중현,장재식,서영범,윤병구,박건욱,김성자,김용섭,강승완,이구,양창헌,이창우,김욱년,이광헌,서정일 동국대학교 의학연구소 2000 東國醫學 Vol.7 No.-

과립상 세포종은 Schwann 세포 기원으로 생각되며 인체에 비교적 드물게 발생한다. 과립상 세포종은 전신 어느 곳에서나 발견될 수 있으나 주로 혀, 구강, 피부 혹은 유방 등에서 호발하며 드물게 위장관에서 발견된다. 위장관에서는 식도에서 가장 호발하며 다음으로 위, 대장 순이다. 과립상 세포종은 대부분, 특히 위장관에서는 양성이며 소수의 악성 병변이 보고되었다. 이러한 이유와 함께 수술 전의 진단이 어렵기 때문에 과립상 세포종에 대한 근본적인 치료는 현재까지 외과적 절제술이다. 최근에 시도되는 치료방법들로는 내시경적 레이저 치료, 용종절제술, 내시경적 점막 절제술 등이 있다. 저자들은 상부 소화관 내시경검사를 시행하여 식도 과립상 세포종을 진단하고 내시경적 점막 절제술을 시행하여 합병증 없이 퇴원하여 현재 재발없이 경과 관찰중인 1례를 경험하였기에 보고하는 바이다. Granular cell tumors, which occur infrequently, are probably of Schwann cell origin. They can occur almost anywhere in the body but usually affect the tongue, oral cavity, skin, or breasts and are rarely found in the gastrointestinal tracts. The esophagus is the most frequent gastrointestinal site, followed by the stomach and the colon. Granular cell tumors are generally benign, especially in the gastrointestinal tract, some malignant lesions have been reported. For this reason, and also because preoperative diagnosis is difficult, the standard treatment for granular cell tumor has until now been surgical excision. In recent years, other therapeutic methods is endoscopic laser therapy (ELT), polypectiomy, endoscopic mucosal resection (EMR). We report a case of esophageal granular cell tumor which was diagnosed by an endoscopy and managed using an endoscopic mucosal resection without complication.

Fluoxetine 투여와 관련된 양측 측두하악관절 손상 1예

배치운,김연주,김태석,김정진,이창욱,이수정,이철,백인호 大韓神經精神醫學會 2004 신경정신의학 Vol.43 No.4

We hereupon present a case of injured temporomandibular joint (TMJ) associated with fluoxetine monotherapy-inducedrepeated yawning. Further information is needed regarding the relationship between fluoxetine administration and clinically significant yawning. Clinicians should be more careful to listen to their patients when they describe unexpected reactions to medications.

정신분열병과 Glutathione S-Transferase M1유전자 다형성

배치운,조자현,김연주,김태석,김정진,이창욱,이수정,전태연,이철,백인호 大韓神經精神醫學會 2004 신경정신의학 Vol.43 No.5

Objectives : This study aimed to test the possible association between Glutathione S-Transferase Ml gene (GSTMl) variants and schizophrenia. Methods : One hundred and eleven inpatients with schizophrenia and 130 healthy controls were recruited. Genotyping was performed by polymerase chain reaction-based method. Results : The GSTMl null genotype was significantly more frequent in patients with schizophrenia than in controls (p=0.014, odd ratio=1.93, 95% confidence interva1=1.115-3.351), while GSTMl genotype vahants were not associated with either tardive dyskinesia (TD) or total Abnormal Involuntary Movement Scale (AIMS) scores. Conclusion : The present study suggests that the GSTMl polymorphism may confer susceptibility to the development of schizophrenia but not to TD, at least in Korean population.

지역4-H조직의 내적 적합성에 관한 문화기술적 연구

김진모,김진군,전영욱,이정은,최영창,이은영 한국농업교육학회 2008 농업교육과 인적자원개발 Vol.40 No.2

이 연구의 목적은 지역4-H조직의 내적 적합성을 탐색하고 이를 기술하는데 있었다. 2006년 8월부터 10월까지 약 3개월 동안 지역4-H후원회 회장 및 임원진 3명, 지역4-H연맹 회장 1명, 학교4-H 지도교사 4명, 지역의 영농4-H회장 1명, 시·군 농업기술센터 소장 및 4-H담당자 9명을 주요 연구 참가자로 하여 심층면담을 통해 자료를 수집하였다. 수집한 자료를 분석한 결과는 다음과 같았다. 첫째, 지역4-H조직 관련자들이 인식하는 지역4-H조직의 주요성과 격차로, ① 민간4-H조직을 중심으로 한 자율적이고 독립적인 활동 부재, ② 지역4-H조직 간 다양한 종류의 협력 부재, ③ 지역사회에서 4-H활동에 대한 가치 인식 부족이 나타났다. 둘째, 지역4-H조직의 핵심 과업으로 ① 4-H의 가치 및 이념에 부합하고, 지역의 실정에 맞는 프로그램 확보, ② 지역4-H 조직 간 협력적 네트워크 확립, ③ 4-H에 대한 지역사회의 관심 및 지지 확보가 나타났다. 셋째, 지역4-H조직의 내적 부적합성으로는 ① 인원 확보의 어려움과 핵심과업에 대한 전문성 결여, ② 관료화되고 경직된 낡은 문화, ③ 조직적 자원의 축소 및 조직 간 낮은 네트워크의 수준이 도출되었다. The purpose of this study was to describe and understand internal fit in Local 4-H Organization. The main participants of this study were one leader and two members of Local 4-H Society for the support, one leader of Local 4-H Association, four School 4-H teacher, one leader of Local farm 4-H, 9 local agricultural extension workers. The data were collected through in-depth interview with them from August, 2006 to October, 2006. The Results from this study were as follow: 1. Key performance gaps of local 4-H organizations were identified: ① lack of local 4-H based activities, ② lack of various types of partnership between local 4-H organizations, ③ lack of understanding value of 4-H activities in the communities. 2. Key tasks of local 4-H organizations were identified: ① developing local 4-H programs based on 4-H's values and ideas, ② establishing the cooperative networks among local 4-H organizations, ③ ensuring the interest and support about 4-H in the communities. 3. Internal misalignments of local 4-H organizations were identified: ① difference of recruitment and lack of expertise, ② bureaucratic and rigid cultures, ③ decrease in organizational support and low level of network among organizations.