Statistical Studies Based on SiO and $H_2O$ Maser Survey toward Evolved Stars

김재헌,조세형,김상준,Kim, Jaeheon,Cho, Se-Hyung,Kim, Sang-Joon 한국천문학회 2012 天文學會報 Vol.37 No.2

We report extensive statistical analyses based on the simultaneous observational results of SiO and $H_2O$ masers toward 166 known both SiO and $H_2O$ maser sources (Kim et al. 2010), 83 known SiO maser sources (Cho & Kim 2012 submitted), and 152 known $H_2O$ maser sources (Kim et al. 2012 in preparation). We investigate mutual relations between SiO and $H_2O$ maser properties (peak and total flux density ratios, full line width ratios, and velocity structures etc.) according to stellar pulsation phases and type of evolved stars. These statistical results are compared with monitoring observational results of some individual stars. In addition, a relation between the full line width of SiO/$H_2O$ masers and stellar mass loss rates is examined. For 401 observed stars, we also investigate characteristics of SiO and $H_2O$ maser properties related with evolutionary stages in the IRAS two-color diagram.

디지털 크리처 제작 기술 동향

김재헌,성만규,김상원,장성준,김예진,최병태,Kim, Jae-Heon,Seong, Man-Gyu,Kim, Sang-Won,Jang, Seong-Jun,Kim, Ye-Jin,Choe, Byeong-Tae 한국전자통신연구원 2007 전자통신동향분석 Vol.22 No.4

디지털 크리처란 인간, 동물 그리고 영화 "반지의 제왕"의 "골룸"이나 영화 "괴물"의 "괴물" 같은 상상 속의 캐릭터뿐만 아니라 나무나 숲과 같은 식물을 포함한 실사 수준의 영상으로 표현되는 디지털 생명체를 의미한다. 최근 전세계적으로 흥행에 성공한 블록버스터급의 영화는 대부분 발전한 CG 기술을 바탕으로 감독의 상상력이 그대로 상으로 옮겨진 디지털 크리처가 등장하고 있으며 이로 인해 종래의 단편적인 역할에서 영화의 흥행을 좌우하는 핵심 기술로서 자리잡아 가고 있다. 특히, 영화 등 디지털콘텐츠의 세계시장 규모를 생각하면 이러한 기술의 경제적인 중요성은 매우 크다고 할수 있다. 본 논문에서는 이러한 디지털 크리처를 제작하기 위해 필요한 대표 기술들의 기술동향을 분석하고자 한다.

반도체 광증폭기를 이용한 10 Gb/s 전광 AND논리소자

김재헌,김병채,변영태,전영민,이석,우덕하,김선호,Kim, Jae-Hun,Kim, Byung-Chae,Byun, Young-Tae,Jhon, Young-Min,Lee, Seok,Woo, Deok-Ha,Kim, Sun-Ho 한국광학회 2003 한국광학회지 Vol.14 No.2

반도체 광증폭기의 이득포화원리를 이용한 전광 AND논리소자가 10 Gb/s에서 처음으로 구현되었다. 먼저 첫 번째 반도체 광증폭기에 B 신호를 입력시켜 반전된 신호인 Boolean (equation omitted)이 얻어졌다. 이와 같이 반전된 신호는 두 번째 반도체 광증폭기에 A신호와 함께 동시 입력되어 AND논리소자의 특성이 얻어졌다. By using gain saturation of semiconductor optical amplifiers (SOAs), an all-optical AND gate at 10 Gb/s has been successfully demonstrated. Firstly, Boolean (equation omitted) has been obtained using the first SOA with signal B and clock injection. Then, the all-optical AND gate is achieved using the second SOA with signals A and (equation omitted) injection.

슬관절의 운동학적 분석

김재헌,Kim, Jae-hun 대한고유수용성신경근촉진법학회 2008 PNF and Movement Vol.6 No.1

Purpose : To describes the important aspects of knee joint movement and function used when applying PNF technique to the lower limb. Method : The knee was a very important roles in the lower limb movement and ambulation. This study summarizes the physiologic movement of knee to the PNF lower extremity patterns. Result : The tibiofemoral joint is usually described as a modified hinge joint with flexion-extension and axial rotation by two degrees of freedom movement. These arthrokinematics are a result of the geometry of the joints and the tension produced in the ligamentous structures. The patellofemoral joint is a sellar joint between the patella and the femur. Stability of the patellofemoral joint is dependent on the passive and dynamic restraints around the knee. In a normal knee the ligaments are inelastic and maintain a constant length as the knee flexes and extends, helping to control rolling, gliding and translation of the joint motions. Conclusions : It is important to remember that small alterations in joint alignment can result in significant alterations in patellofemoral joint stresses and that changes in the mechanics of the patellofemoral joint can also result in changes in the tibiofemoral compartments. Successful treatment requires the physical therapist to understand and apply these arthrokinematic concepts. When applied to PNF low extremity patterns, understanding of these mechanical concepts can maximize patient function while minimizing the risk for further symptoms or injury.

벼(Orysa sativa L.) 뿌리로부터 분리된 내생 Streptomyces 균주의 동정 및 특성

김재헌,이준관,Kim, Jae-Heon,Lee, Jun-Kwan 한국미생물학회 2011 미생물학회지 Vol.47 No.4

천안의 단국대학교 근처에서 채취된 벼 뿌리로부터 내생 방선균 한 주를 분리 동정하였다. 표면 살균된 벼 뿌리를 분리 배지 위에 올려 놓고 배양하면 4주 후에 뿌리 표면에 형성된 방선균 콜로니를 볼 수 있었다. 이 중에서 한 균주 JK-5를 분리하여 동정하였다. 16S rDNA 염기서열을 확인한 결과 이 분리균주 JK-5는 Streptomyces diastaticus subsp. ardesiacus와 동일한 균주였다. 형태학적 관찰과 화학분류학적 결과에 의해 분리균주 JK-5의 분류학적 위치를 확인하였다. 기중균사의 형태는 flexible하며 포자사슬은 타원형의 약 30개 정도의 매끄러운 포자로 이루어 졌다. 세포벽은 L,L-diaminopimelic acid를 포함하고 있었다. 당 분석에서는 특이적인 당이 발견되지 않았다. 지방산으로는 anteiso-15:0, anteiso-17:0, iso-16:0 가 주요 성분이었다. 퀴논 분석결과 MK-9 ($H_6$)와 MK-9 ($H_8$)이 주요 성분으로 나타났다. GC 함량은 72%로 측정되었다. 식물병원성 곰팡이에 대하여 비교적 높은 항진균활성을 보여 주었다. 벼에 감염된 분리균주 JK-5가 뿌리와 줄기에서 균사체를 형성하며 왕성하게 생장하는 것을 SEM을 통하여 확인하였다. We isolated an endophytic actionmycete from root tissues of rice plant collected from paddy field near Dankook University, Cheonan, Korea. Surface sterilized roots were laid on the selective agar plates and incubated. The powdery actinomycete colonies appeared on the root surface after four weeks incubation. We isolated a strain JK-5 among them and could determine its taxonomical position as Streptomyces diastaticus subsp. ardesiacus by using 16S ribosomal DNA sequencing. The chemotaxonomical and morphological studies confirmed the taxonomical position of the strain JK-5. The shape of aerial hyphae was flexible and they contained spore chains with more than 30 smooth spherical spores per chain. Cell walls contained LL-diaminopimelic acid. There was no characteristic sugar in whole-cell hydrolysates. The major fatty acids were anteiso-15:0, anteiso-17:0 and iso-16:0. The specific menaquinones, MK-9 ($H_6$), MK-9 ($H_8$), were detected. The GC content was 72%. Antifungal activities of the strain JK-5 were relatively strong against fungal plant pathogens. The endophytic growth of the strain JK-5 was confirmed by SEM observation of the root and stem of the infected rice plant.

슬관절 전치환술 이후의 고유수용성 감각 변화

김재헌,Kim, Jae-Hun 대한고유수용성신경근촉진법학회 2011 PNF and Movement Vol.9 No.1

Purpose : The purpose of this article was to review the literature on change of knee position sense after total knee replacement intervention in knee rehabilitation. Methods : This review outlines scientific findings regarding different literature data in knee rehabilitation, and discusses proprioceptive change of knee joints after total knee replacement intervention. Result : Severe pain and diminished joint sensation may precipitate degenerative changes of knees joint, and a strong association between decreased proprioception and function has been identified in elderly patients with knee osteoarthritis. Total knee replacement(TKR) of the knee joint are effective surgical procedures in osteoarthritis patients, resulting in decreased pain, and improved physical function and quality of life in patients. After total knee replacement, joint position sensation is partially recovered, which may improve functional stability of the knee, but aspects of physical functioning are not fully restored to preoperative status. Conclusions : Thus, recovery rate in proprioception after TKR also is considered to be important because it may be a significant risk factor in failure of total knee replacement and knee rehabilitation intervention.

Streptomyces coelicolor A3(2)의 Acetyl Xylan Esterase를 발현하는 Escherichia coli의 과산화수소 저항성

김재헌,최원일,윤석원,정상운,오충훈,Kim Jae-heon,Choi Won-ill,Youn Seock-won,Jung Sang Oun,Oh Chung-Hun 한국미생물학회 2004 미생물학회지 Vol.40 No.3

Streptomyces coelicolor A3(2)의 acetyl xylan esterase (AxeA)가 Escherichia coli의 과산화수소 저항성에 미치는 영향을 알아보고자 하였다. AxeA 발현은 isopropyl-$\beta$-thiogalactoside로 유도되었고 생산된 AxeA는 SDS-polyacrylamide gel electrophoresis방법으로 확인하였다. AxeA 발현에 따른 과산화수소 저항성의 변화를 E. coli의 생장곡선과 생존율을 통하여 조사하였다. AxeA가 발현되지 않으면 모든 처리 농도 (1 mM, 2.5mM, 5mM)에서 균의 사멸이 일어났다. AxeA가 발현되는 조건에서는 5mM을 제외한 과산화수소 1mM와 2.5mM에서 E. coli의 사멸이 저지되었다. 또한 1.5mM의 과산화수소에 대한생존율이 59%에서 74%로 높다졌다. 동시에 E. coli의 최고생장온도에서에 근접한 $45^{\circ}C$에서의 생존율도 증가되는 결과를 얻었다. 그러므로 AxeA 단백질은 산화적 스트레스와 온도스트레스에 대해 교차 저항성을 나타내는 역할을 한다고 결론지었다. We investigated hydrogen peroxide resistance of Escherichia coli possessing acetyl xylan esterase(AxeA) of Streptomyces coelicolor A3(2). The induction of AxeA production by isopropyl-$\beta$-thiogalactoside was confirmed by SDS-polyacrylamide gel electrophoresis. The differences in growth between induced and non-induced E. coli were determined by the changes in optical density of cultures after hydrogen peroxide treatment The lethal effect of hydrogen peroxide was observed for non-induced cultures at all concentrations tested in this study (lmM, 2.5mM and 5mM). However, cultures induced for AxeA production resisted the lethal effect, except at 5mM where cells were killed irrespective of the AxeA production. The axeA induction increased survival against 1.5mM hydrogen peroxide from 59% to 74%. In addition, AxeA producing E. coli showed increased survival at $45^{\circ}C$, near maximum growth temperature. Therefore, it was concluded that AxeA conferred a cross-resistance upon the bacterium against both oxidative- and heat stress.

Streptomyces coelicolor A3(2)의 철 함유 superoxide dismutase 2에 의한 중금속 독성 완화

김재헌,이현경,Kim, Jae-heon,Lee, Hyeon-kyoung The Microbiological Society of Korea 2017 미생물학회지 Vol.53 No.2

납, 아연, 카드뮴에 의한 미생물 생장 저해를 변형된 Tris minimal medium을 사용하여 측정하였다. Escherichia coli 균주에 대한 독성의 세기는 아연 > 카드뮴 > 납 순으로 나타났고 Streptomyces coelicolor A3(2)의 철 함유 superoxide dismutase 2를 과발현하는 E. coli 균주는 중금속 저항성이 증가되었음을 알 수 있었다. Bacterial growth inhibition by lead, zinc and cadmium was measured by using modified Tris minimal medium. The toxicity against Escherichia coli strain was in the order of zinc> cadmium> lead, and the Escherichia coli strain overexpressing iron-containing superoxide dismutase 2 of Streptomyces coelicolor A3(2) was found to have resistance to heavy metals.

발과 족관절의 운동학적 분석

김재헌,Kim, Jae-Hun 대한고유수용성신경근촉진법학회 2008 PNF and Movement Vol.6 No.3

Purpose : To describes the important aspects of the foot and ankle movement and function used when git and balance strategy. Method : The foot and ankle was a very important roles in the lower limb movement and gait. This study summarizes the physiologic movement of knee to the PNF lower extremity patterns. Result : The ankle joint composed of the talocural joint, the subtalarl joint, transverse tarsal joint, talocalcaneonavicular joint. The onset of dorsiflexion muscle activity starts in pre swing gait patterns. First contract muscle is the extensor hallucis. Activity of tibialis anterior and extensor digitorum longus quickly follows in mid swing gait phase. During stance phase, the soleus and gastrocnemius muscle provided plantar flexor torque, which muscle reacts quickly to restrain ankle dorsiflexion, and contributes modulated control of the ankle motion in gait patterns. Conclusions : The understanding of ankle kinematics, could provide a good therapeutic approach for improving gait patterns in patients with various pathological condition.

20대 정상 성인 남녀의 요추 원위치 돌아오기 오류의 차이

김재헌,배성수,Kim Jae-Hun,Bae Sung-Soo 대한물리치료학회 2003 대한물리치료학회지 Vol.15 No.4

Although many current low back pain exercise incorporate proprioceptive training, very little research has been performed on proprioception of the low back. To determine wether reposition error is different in male than female. Eighteen young individuals took part in the research, seven male and eleven female. The 3-dimensional position of the lumbar was measured with a CMS70P. Reposition error was calculated as the absolute difference between the neutral position and return position. No significant differences in reposition error were found between male and female. No significant correlations were identified between reposition error and movement direction.