일방향 CFRP적층판의 모드II 동적 층간파괴인성 평가

김지훈,정태훈,이현,양인영,조규재,심재기,Kim, Ji-Hoon,Jeong, Tae-Hoon,Lee, Hyun,Yang, In-Young,Cho, Gyu-Jae,Sim, Jae-Ki 한국안전학회 2000 한국안전학회지 Vol.15 No.4

In this paper, an investigation was performed on the ModeII dynamic interlaminar fracture toughness of unidirectional CFRP laminates. The stacking sequences used in this experiment are two kinds of [$0_20$] and [$0_{10}F_20_{10}$]. In the experiments, Split Hopkinson's Bar test was applied to dynamic and notched flexure test. The Mode II fracture toughness of each unidirectional CFRP was estimated by the analyzed deflection of the specimen and J-Integral with the measured impulsive load and reactions at the supported points. As an experimental results, the specimen [$0_{10}F_20_{10}$] appears greater than that of [$0_20$] for the J-integral and displacement velocity at a measuring point within the range of experiment.

후포분지 홀로세 퇴적물의 유기물에 대한 지화학 분석 결과 및 의미

김지훈,박명호,공기수,한현철,정태진,최지영,김진호,강무희,이치원,오재호,Kim, Ji-Hoon,Park, Myong-Ho,Kong, Gee-Soo,Han, Hyun-Chul,Cheong, Tae-Jin,Choi, Ji-Young,Kim, Jin-Ho,Kang, Moo-Hee,Lee, Chi-Won,Oh, Jae-Ho 대한자원환경지질학회 2010 자원환경지질 Vol.43 No.1

Geochemical approaches on the two recovered piston cores were performed to understand the characteristics of organic matters and the influence of the sea level variation of the East Sea in the Hupo Basin since the Holocene. The analyzing results on organic components (TOC and TN), and isotopic compositions of organic matters showed the variation to core locations and sampling depths. In core 08HZP-01, their values were gradually changed with depth from 4 mbsf to seafloor. However, rapid variation was observed at the boundary of 4.71 mbsf (meter below seafloor) in core 08HZP-03. Based on TOC/TN, $\delta^{13}C_{org}$ and $\delta^{15}N_{org}$, the origin of organic matters in the Hupo Basin can be divided into three groups; 1) predominant marine algae, 2) $C_3$ land plant, and 3) mixture of $C_3$ land plant and marine/freshwater algae. It is likely that the vertical and spatial variations of organic and isotopic compositions reflect the shifts in sedimentary environment (including sediment transportation) by ocean currents and sea-level changes and others during the Holocene period. 동해안의 후포분지에서 채취한 두 개의 피스톤 코어를 이용하여 후포분지에서의 홀로세 퇴적물 내 유기물의 특징 및 동해 해수면 변화와의 관계를 규명하고자 지화학적 접근을 시도하였다. 채취한 시료에 대한 유기물 성분 분석(TOC와 TN)과 유기물 동위원소($\delta^{13}C_{org}$와 $\delta^{15}N_{org}$) 분석 결과들은 코어와 시료 채취 심도에 따라 분석값들이 특징적으로 변화한다. 코어 08HZP-01에서는 4 mbsf(meter below seafloor)에서 코어 표면까지 비교적 채취 심도가 상부로 갈수록 지화학 분석값들이 점이적으로 증가하지만, 코어 08HZP-03에서는 4.71 mbsf를 기준으로 상부와 하부에서 급격한 지화학 분석값들의 변화가 발생한다. 유기물의 TOC/TN과 $\delta^{13}C_{org}$와 $\delta^{15}N_{org}$의 값을 종합적으로 고려하였을 때, 후포분지의 유기물은 해양 조류 기원이 우세한 집단, $C_3$ 육성 식물 기원이 우세한 집단, 해성/육성 조류와 $C_3$ 육성 식물의 혼합기원이 우세한 집단으로 구분할 수 있다. 이러한 퇴적물 내 유기물의 심도에 따른 특성 및 기원 변화는 주로 홀로세 동해 해류와 해수면 등의 변화에 따른 퇴적환경 변화 (퇴적물 이동 포함)에 기인한 것으로 보인다.

우유에서 분리된 포도상구균속 세균의 항생제 감수성

김지훈,고문주,김가희,이승훈,최성숙,Kim, Ji-Hoon,Ko, Mun-Joo,Kim, Ka-Hee,Lee, Seung-Hoon,Choi, Sung-Sook 한국미생물학회 2010 미생물학회지 Vol.46 No.4

본 연구에서는 우유 시료에서 포도상구균속 세균을 분리하고 각 균종을 동정하고 항생제 감수성을 검사하였다. 2009년 1월부터 2009년 10월까지 경기 북부지역 15개 축산 농가에서 287개의 우유 시료를 수집하여 총 79개의 포도상구균속 세균을 분리 동정하였다. 가장 우세한 비율로 분포하는 세균은 S. aurues (43.03%)였으며 coagulase negative staphylococci (CNS) 중에서는 S. chromogenes (24.05%)가 가장 우세하게 분포하였다. 9종의 항생제에(ampicillin, chloramphenicol, ciprofloxacin, erythromycin, gentamicin, oxacillin, teicoplanin, tetracyclin, vancomycin) 대한 감수성 검사를 실시한 결과 대다수의 항생제에 대한 감수성 비율이 높았으나 ampicillin (56.96%)과 oxacillin (39.23%)에 대한 내성 균주의 비율이 높게 나타났다. 31종의 oxacillin 저항성균주 중 8개의 균주가 methicillin 내성에 관여하는 mecA 유전자를 보유하고 있었다. The prevalence and antimicrobial susceptibilities of Staphylococcal isolates from bovine milk samples were assessed. From January 2009 to October 2009, a total 287 bovine milk samples were randomly collected from 15 stock raising farms located in northern area of Kyunggi province and cultured for the presence of Staphylococci spp. A total 79 staphylococcal isolates were recovered from the milk samples. The predominant isolates were S. aureus (43.03%) and S. chromogenes (24.05%). Antimicrobial resistance patterns of 79 Staphylococcal isolates against ampicillin, chloramphenicol, ciprofloxacin, erythromycin, gentamicin, oxacillin, teicoplanin, tetracyclin, and vancomycin were tested. Staphylococcal isolates revealed the highest resistance to ampicillin (56.96%) and oxacillin (39.23%). Of 31 oxacillin resistance strains, 8 strains carry mecA gene which is responsible for methicillin resistance.

후두 결핵의 임상 양상 분석: 최근 10년간 단일 기관의 경험

김지훈,공태훈,최홍식,변형권,Kim, Ji-Hoon,Kong, Tae Hoon,Choi, Hong-Shik,Byeon, Hyung Kwon 대한후두음성언어의학회 2020 대한후두음성언어의학회지 Vol.31 No.2

Background and Objectives The overall incidence of laryngeal tuberculosis (LT) has generally decreased over the recent years, yet there is still a discrete population of patients newly diagnosed with the disease. This study is aimed to examine the patients with LT over the recent 10 years and to investigate the changes in clinical pattern with respect to the past period. Materials and Method A retrospective review has been performed on 20 patients who have been initially diagnosed with LT between 2005 and 2015. Results The age of the patients ranged from 25 years to 95 years with an average age of 45.6 years. Seventeen patients (85%) showed hoarseness, which was the most common clinical symptom. Most affected lesion was the true vocal cord. Laryngoscopic examination showed various clinical manifestations: polypoid 30%, granulomatous 25%, nonspecific 25%, ulcerative 20%. A variety of methods were used for diagnostic confirmation of LT [acid-fast bacilli (AFB) smear 45%, AFB culture 40%, polymerase chain reaction 30%, surgical pathology 45%]. Coexisting pulmonary tuberculosis (PT) was detected in 10 patients (50%). Relative to the patients with inactive PT or normal lung status, those with active PT showed higher incidence of laryngeal lesions located in areas other than true vocal cord (p=0.050). Conclusion Based on the analytic results from this study, laryngologists should recognize the changes in the recent clinical patterns of LT and always be ready for clinical suspicion of this disease on such atypical laryngeal findings which can often mimic laryngeal malignancies to provide the pertinent treatment.

혈액질환에 속발하는 이차성 위암

김지훈,지성배,허훈,진형민,김욱,김동욱,이종욱,민우성,김춘추,전해명,Kim, Ji-Hoon,Jee, Sung-Bae,Huh, Hoon,Chin, Hyung-Min,Kim, Wook,Kim, Dong-Wook,Lee, Jong-Wook,Min, Woo-Sung,Kim, Choon-Choo,Jeon, Hae-Myung 대한위암학회 2007 대한위암학회지 Vol.7 No.4

Purpose: Patients with hematologic diseases such as chronic myeloid leukemia (CML) or chronic lymphoid leukemia (CLL) are known to have an increased chance of acquiring a secondary neoplasm. Stomach cancer is one of the most common malignant diseases in Korea, and we investigated whether the incidence of secondary stomach cancer in patients with a hematologic disease increases, in order to determine if a more intensive screening program for detecting secondary gastric cancer was required. We also investigated the safety of performing a gastrectomy in hematologic disease patients. Materials and Methods: From 1992 to 2006, the medical records of 8376 patients diagnosed with one of the six common hematologic diseases were reviewed. Results: Nine secondary stomach cancers were found among the 8376 patients during the 15-year observation period. No surgical-related complications occurred, and there was no recurrence of stomach cancer if detected early. Conclusion: It seems that a more intensive screening program for detecting secondary gastric cancer in hematologic disease patients is not required, and surgery is not risky in these patients. 목적: 만성 골수성 백혈병이나 말성 림프구성 백혈병에서 이차성 암의 위험은 증가하는 것으로 알려져 있다. 백혈병을 비롯한 혈액질환을 가진 환자에서 우리나라에서 가장 흔한 암 가운데 하나인 위암의 위험이 증가하는지 조사하여 혈액질환 환자를 대상으로 위암에 대한 보다 적극적인 검진이 필요한지 알아보고자 하였다. 또한 응고장애나 면역저하와 같은 수술에 관련된 위험인자가 있을 수 있는 혈액질환 환자에서 위암 수술이 안전하게 이루어질 수 있는지에 대해 조사하고자 하였다. 대상 및 방법: 지난 15년가 성모병원에서 백혈병 및 다발성 골수종, 재생불량성 빈혈로 진단받은 8,376명의 환자를 대상으로 의무기록을 후향적으로 조사하였다. 결과: 총 9예의 이차성 위암이 확인되었다. 감염이나 출혈등 수술관련 합병증은 발생하지 않았으며, 조기에 발견된 경우 재발도 관찰되지 않았다. 결론: 위암의 빈도가 일반인에 비해 크게 증가하지 않아 혈액질환 환자에서 이차성 위암의 감시를 위한 집중적인 프로그램이 따로 도입되어야 할 필요성은 없는 것으로 생각되며, 혈액질환 환자의 위암 수술에 있어 합병증도 크게 증가하지는 않는 것으로 생각된다.

근위부 위절제술 후 재건 술식에 따른 경과 관찰

김지훈,육정환,김병식,오성태,Kim, Ji-Hoon,Yook, Jeong-Hwan,Kim, Byung-Sik,Oh, Sung-Tae 대한위암학회 2006 대한위암학회지 Vol.6 No.1

목적: 근위부 위절제술 후 식도-위 문합술을 시행받은 환자에서 문합부 협착, 역류성 식도염 등이 드물지 않게 발생한다. 저자들 역시 이러한 합병증을 경험하였고 이를 극복하기 위한 방법으로 공장간치술을 시행하였으며 식도-위 문합술과 공장간치술 간의 경과 관찰을 통해 보다 나은 재건 술식을 찾고자 하였다. 대상 및 방법: 1998년 6월부터 2002년 12월까지 울산의대 서울아산병원 외과에서 상부위암 혹은 위상부의 위장관기질종양으로 진단받고 근위부 위절제술을 시행한 환자를 대상으로 재건 술식에 따른 수술시간, 수술 후 증상, 체중변화, 추적관찰 시 시행한 내시경 소견 등을 비교하였다. 결과: 대상 환자 총 33명의 평균연령은 59세였고, 남녀 비는 3 : 1이었다. 식도-위 문합술을 시행한 환자는 25명, 공장간치술을 시행한 환자는 8명이었다. 통과장애, 속쓰림, 신트림, 구토 등의 증상을 관찰하였으며 식도-위 문합술 환자에서 통과장애 12예, 구토 3예, 속쓰림 4예, 신트림 4예가 관찰되었으며, 공장간치술 환자에서는 통과장애 12예, 구토 3예가 있었고, 속쓰림과 신트림은 관찰되지 않았다. 수술 후 체중변화는 1개월 후 수술 전 체중의 90%까지 감소한 경우가 식도-위 문합술 환자에서 7예, 공장간치술 환자에서 없었다. 수술 후 추적 내시경 검사 결과 역류성 식도염이 관찰된 경우는 식도-위 문합술 환자에서 9예, 공장간치술 환자에서 0예였다. 문합부위 협착으로 인해 풍선 확장술이 필요하였던 경우가 식도-위 문합술 환자에서 4예, 공장간치술 환자에서 1예가 있었다. 결론: 상부 위절제 시 재건방법으로 역류성 식도염 및 여러 소화기 증상을 예방하기 위해 공장간치술이 식도-위문합술의 대안이 될 수 있다고 생각한다. 하지만 통계적 유의성을 가지기 위해 더 많은 대상군이 포함되어야 할 것이다. Purpose: A proximal gastrectomy is performed for gastric cancer in the upper part of the stomach to preserve the function of the stomach after surgery. An esophagogastrostomy is one of the common reconstruction methods for a proximal gastrectomy, but this method results in a high incidence of reflux esophagitis. This study was undertaken to compare subjective and functional results between esophagogastrostomy and jejunal interposition reconstructions. Materials and Methods: From June 1998 to December 2002, proximal gastrectomies were performed in 33 patients with tumors in the upper third of the stomach; 8 had reconstruction using jejunal interposition between the esophagus and the remnant stomach (JI group) while 25 had reconstruction using esophagogastrostomy (EG group). The postroperative courses of the patients were reviewed in terms of symptoms, weight changes, and endoscopic findings. Results: The mean age of the patients was 59 years; 26 were men and 7 were women. There were no significant differences in general complications, operating times, or histologic features between the two groups. Fifty-two percent (52%) of the EG group complained of dysphagia, and 16% them experienced heartburn and acid belching. Twelve percent (12%) of the JI group complained of dysphagia, but heartburn and acid belching did not occur. Incidences of reflux esphagitis (36%) and balloon dilatation for anastomotic stricture (16%) were more common in the EG group than in the JI group (0% and 12%). Conclusion: To prevent or minimize complications, such as reflux esophagitis and postoperative symptoms, a proximal gastrectomy with a jejunal interposition is an alternative method as an organ-preserving surgical strategy to improve quality of life for patients. (J Korean Gastric Cancer Assoc 2006;6:1-5)

$La_2CuO_4$ 구조를 갖는 $(C_4H_9NH_3)_2PbI_4$의 합성 및 분석

김지훈,박성훈,최동식,Kim, Ji Hoon,Park, Sung Hoon,Chair, Tong Seek 대한화학회 1998 대한화학회지 Vol.42 No.5

족관절의 골절-탈구에 대한 임상적 고찰

김지훈,송재광,서진수,Kim, Ji Hoon,Song, Jae Gwang,Suh, Jin Soo 대한족부족관절학회 2013 대한족부족관절학회지 Vol.17 No.3

Purpose: We evaluate clinical manifestations and radiologic features of ankle fracture & dislocation, as well as the usefulness of computed tomography on posterior ankle fracture & dislocation to study factors contributing to ankle fracture & dislocation. Material and Methods: Ankle dislocation was defined as the center of talar body being translated over the cortex of tibia on AP or lateral view on simple X-ray. Surgical treatments of 30 patients from January 2007 to March 2012 were categorized according to the injury mechanism, the direction of dislocation and fracture site. Joint involvement of posterior malleoalr fracture was evaluated through simple x-ray and computed tomography. We treated surgically if posterior malleolus fracture involves more than 25% of dital tibial articular surface. Thereafter, clinical outcomes were identified through radiographs and by using the AOFAS score. Results: The mean age was 42(13-78) years old, and slip down was the most common injury mechanism (13 cases). Car accident (6 cases) and fall accident (4 cases) were the next frequently found injury mechanisms. As for the types of ankle fracture, posterior fracture and dislocation (21 cases, 43.3%) was most commonly found. Out of these 21 cases, 15 cases involved trimalleolar fracture, and 19 cases were associated with posterior malleolar fracture. Danis-weber type B and C patients were 11 cases and 10 cases respectively. Articular involvement of posterior malleolar fracture turned out to be average 27.9%(5.1%~49.1%) on simple x-ray. The rate was evaluated as average 31.7%(12.6%~55.3%) on computed tomography which was conducted 15 times, and led us to more meaningful data. Conclusion: Anterolateral fracture and dislocation often accompanied open dislocation. Posterior fracture dislocation was most commonly found. Posterior malleolus was an important factor that ensures posterior stability of the ankle joint. Computed tomograph is useful to evaluate the articular involvement of posterior malleolar fracture.

The Interplay between Star Formation and AGN Activities : A Case Study of LQSONG

김지훈,임명신,김도형,Kim, Ji Hoon,Im, Myungshin,Kim, Dohyeong 한국천문학회 2012 天文學會報 Vol.37 No.2

One of the most intriguing questions regarding black hole (BH)-galaxy co-evolution picture is how the BH accretion, or active galactic nucleus (AGN) activity is linked to star formation (SF) activity. While it is suggested that AGN luminosity of quasars correlates with SF luminosity, it is still unclear how AGN activity is connected to SF activity based on host galaxy properties. Utilizing AKARI's unique slit-less spectroscopic capability and wavelength coverage, we probed star formation activity of several types of AGNs by measuring the PAH 3.3 ${\mu}m$ emission. First, we detected the PAH 3.3 ${\mu}m$ emission from seven out of 27 Seyfert type-1 galaxies at z~0.36. While these galaxies deviate significantly from the local Mbh-${\sigma}$ relation meaning their black holes proceed the host galaxies in terms of evolution, they appear to follow the correlation between nuclear SF and AGN activities of local Seyfert type-1 galaxies. This implies that SF and AGN activities are directly connected at the nuclear region for these Seyfert type-1 AGNs. We also obtained 2-5 ${\mu}m$ spectra for subsamples of Quasar Spectroscopic Observation in Near-infrared Grism (QSONG) which consists of reverberation-mapped AGNs and PG-QSOs. We detected the PAH 3.3 ${\mu}m$ emission from 16 out of 31 reverberation-mapped AGNs and 10 out of 49 PG-QSOs and measured their line strengths. We present the correlations between SF and AGN activities and discuss if there is any dependency of the correlations on properties of host galaxies, such as morphology, or the presence of radio jets.

백부자산(白附子散)이 자외선 조사된 피부 손상과 색소침착에 미치는 영향

김지훈,홍승욱,Kim, Ji-Hoon,Hong, Seong-Ug 대한한방안이비인후피부과학회 2008 한방안이비인후피부과학회지 Vol.21 No.1

Objective : The purpose of this study is to examine the effects of Baickbujasan(BB) on the skin damage and depigmentation. Method : The inhibition of tyrosinase activity, melanogenesis and cell viability in cultured B16 melanoma cells were measured. In order to test effects of reduction of melanogenesis, B16 F-10 mouse melanoma stem line was employed to extract melanin from cultured cell, where BB was added or not, and was dissolved in alkali for colorimetric analysis. Also, in order to test skin alteration in C57BL/6 after UV irradiation, the animals were grouped into a UV urradiation group and UV irradiation after BB application group. Dopa oxidase tissue staining was excuted to invesitage the change in the distribution of active melanin cell. The distribution of active melanin cell in inner skin of iNOS after damage from UVB irradiation and the manifestation condition of P53 which takes part in natural death of keratinocyte were examined. Result : The results indicate that BB has significant effects on tyrosinase activity, and melanogenesis in vivo test. BB seems to reduce C57BL/6, external dermatological damage, for instance, erythematous papule, eczema, loss of keratinocyte, reduction in pus, and relieves dermatological damages. Conclusion : BB can be applied externally for UV protection and depigmentation.