Light-extraction efficiency control in AlGaN-based deep-ultraviolet flip-chip light-emitting diodes: a comparison to InGaN-based visible flip-chip light-emitting diodes.

Lee, Keon Hwa,Park, Hyun Jung,Kim, Seung Hwan,Asadirad, Mojtaba,Moon, Yong-Tae,Kwak, Joon Seop,Ryou, Jae-Hyun Optical Society of America 2015 Optics express Vol.23 No.16

<P>We study light-extraction efficiency (LEE) of AlGaN-based deep-ultraviolet light-emitting diodes (DUV-LEDs) using flip-chip (FC) devices with varied thickness in remaining sapphire substrate by experimental output power measurement and computational methods using 3-dimensional finite-difference time-domain (3D-FDTD) and Monte Carlo ray-tracing simulations. Light-output power of DUV-FCLEDs compared at a current of 20 mA increases with thicker sapphire, showing higher LEE for an LED with 250-관m-thick sapphire by ~39% than that with 100-관m-thick sapphire. In contrast, LEEs of visible FCLEDs show only marginal improvement with increasing sapphire thickness, that is, ~6% improvement for an LED with 250-관m-thick sapphire. 3D-FDTD simulation reveals a mechanism of enhanced light extraction with various sidewall roughness and thickness in sapphire substrates. Ray tracing simulation examines the light propagation behavior of DUV-FCLED structures. The enhanced output power and higher LEE strongly depends on the sidewall roughness of the sapphire substrate rather than thickness itself. The thickness starts playing a role only when the sapphire sidewalls become rough. The roughened surface of sapphire sidewall during chip-separation process is critical for TM-polarized photons from AlGaN quantum wells to escape in lateral directions before they are absorbed by p-GaN and Au-metal. Furthermore, the ray tracing results show a reasonably good agreement with the experimental result of the LEE.</P>

봉독약침이 류마티스 관절염 환자의 관절 통증, 종창 및 급성 염증 반응에 미치는 영향

이상훈,이현종,백용현,김수영,박재경,홍승재,양형인,김건식,이재동,최도영,이두익,이윤호 WHO COLLABORATING CENTRE FOR TRADITIONAL MEDICINE 2003 東西醫學硏究所 論文集 Vol.2003 No.-

Objective In order to study the effects of bee venom(BV) on the pain, edema, and acute inflammatory reactant of rheumatoid arthritis(RA) patients. Methods Patients with RA who met the ACR(American College of Rheumatology) 1987 revised criteria for the diagnosis of RA were treated with the BV therapy twice a week for 3 months. Tender Joint counts, swollen joint counts, Visual analog scale(VAS), morning stiffness, ESR. C-reactive protein(CRP) were analyzed before and after BV therapy. Results The results as follows. 1. Tender joint counts in patients after BV therapy were significantly lower than those before BV therapy(9.0±7.9 vs 15± 11.4, p=0.002). 2. Swollen joint counts of the patients after BV therapy were significantly lower than those before BV therapy(50±61 vs 15±23, p=0.001). 3. VAS in patients after BV therapy was significantly lower than those before BV therapy(608± 17.6 vs 380± 159, p=0.000). 4. Duration of morning stiffness in patients after BV therapy was significantly reduced compared with that before BV therapy(119.1± 112.6 min vs 59.0±89.7 min, p=0.009). 5. ESR and CRP were not significantly changed before and after BV therapy, suggesting BV itself could make inflammatory reaction as well as therapeutic effect. Conclusions BV therapy improved tender joint counts, swollen joint counts and duration of morning stiffness in this study, and further study is needed on long-term effect of BV therapy.

자궁내 태아사망의 임상적 고찰

이권해,이정재,조현철,이석민,이임순,이해혁,김권대,이순곤,남계현 순천향의학연구소 1999 Journal of Soonchunhyang Medical Science Vol.5 No.2

Objective: This study was designed to evaluate diagnosis and complication, prognosis during clinical study of cases of intrauterine fetal death. Methods and materials: This is a clinical study of 56 cases of the intrauterine fetal death among 8064 deliveries at Seoul Sunchunhyang university hospital during 5 years from January, 1994 to December, 1998. Results: The incidence was 0.7%. The age distribution of mothers was 18 - 44 years and was highest in the 25 - 29 years range(46.4%). The parity was the most highest in the nulliparous group(51.8%). The most common gestational weeks was 20 - 28 weeks gestational period(46.4%), and most common presentation was cephalic(73.5%). The most common weights of the intrauterine fetal death was from 5,00gm to 1,000g(48.2%). The mode of the most common delivery was the induction of delivery(57.2%). The etiologic factors were: unknown(42.9%), preeclampsia(17.9%), chorioamnionitis(14.3%), congenital anomaly(12.5%), abruptio placenta(7.1%), cord complication(3.6%), placenta previa, death of one for twin. There were 2 cases of maternal complication(DIC, Uterine atony). Conclusion : Intrauterine fetal death should be diagnosised early and treated properly to reduce risk of the maternal complication.

봉독약침이 류마티스 관절염 환자의 기능회복 및 삶의 질에 미치는 영향

이상훈,이현종,박상민,김수영,박재경,홍승재,양형인,이재동,최도영,김건식,이두익,이윤호 WHO COLLABORATING CENTRE FOR TRADITIONAL MEDICINE 2003 東西醫學硏究所 論文集 Vol.2003 No.-

Objective: To evaluate the effects of bee venom acupuncture(BVA) on the rehabilitation and quality of life in rheumatoid arthritis(RA) patients Methods: Patients with RA were treated with the BVA therapy twice a week for 3 months. Tender joint counts, swollen joint counts, morning stiffness, Erythrocyte Sedimentation Rate(ESR), C-reactive protein(CRP), patient global assessment, physician global assessment, Korean health assessment questionnaire(KHAQ) were estimated and analyzed before and after BVA therapy. Results: Tender joint counts, swollen joint counts, morning stiffness showed significant decrease after BVA therapy. But, as acute inflammatory reactants, ESR showed no significant difference and CRP showed significant increase after BVA therapy. Patient global assessment physician global assessment, and KHAQ index showed significant improvement after BVA therapy. Conclusions: BVA therapy can improve rehabilitation and health-related quality of life RA patients as well as clinical symptom and signs. Further study is required in more population with large scale including acute inflammatory reaction of BVA therapy.

서울의 Penicillinase Producing Neisseria gonorrhoeae 발생빈도(1998)

김재홍,김준호,반재용,이정우,황성주,정준규,정성태,강진문,조흔정,홍창의,정혜신,이한승,김이선,이봉길,이종호,선영우,한기덕,윤성필,이성훈,안종성,박석범,문승현,조항래,김형섭,류지호,황재영,박준홍,손상욱 한양대학교 의과대학 2001 한양의대 학술지 Vol.21 No.1

In recent years, gonorrhea has been pandemic and remains one of the most common STDs in the world, especially in developing countries. For the detection of a more effective therapeutic regimen and assessing the prevalence of Penicillinase Producing Neisseria gonorrhoeae(PPNG), we have been trying to study the patients who have visited the Venereal Disease Clinic of Choong-Ku Public Health Center in Seoul since 1980 by menas of the chromogenic cephalosporin method. In 1998, 93 strians of N. genorrhoeae were isolated, among which 60(64.5%) were PPNG. The prevalence of PPNG in Seoul, which had been decreased to 39% in 1996 after a peak of 74.3% in 1993, is increased to 64.5% in 1998.

추황배(Pyrus pyrifolia Nakai cv. Chuhwangbae) 과피로부터 1종의 Sterol과 3종의 배당체 화합물의 단리·동정

이유건(Yu Geon Lee1),조정용(Jeong-Yong Cho),이현주(Hyun Joo Lee),이용현(Yong Hyun Lee),이상현(Sang-Hyun Lee),한태호(Tae-Ho Han),김월수(Wol-Soo Kim),박근형(Keun-Hyung Park),문제학(Jae-Hak Moon) 한국식품과학회 2013 한국식품과학회지 Vol.45 No.5

본 연구에서는 배의 유용성 증명을 위한 일환으로 배의 화학성분을 분자수준에서 밝히고자 하였다. 이에 배 과피 MeOH 추출물을 용매분획하여 얻은 EtOAc-산성 분획과 EtOAc-중성분획을 대상으로 Sephadex LH-20, silica gel, 그리고 ODS colmn chromatography와 HPLC를 이용하여 정제 및 단리하였다. 그 결과, EtOAc-산성 분획과 EtOAc-중성 분획으로부터 각각 2종씩의 화합물을 단리하였다. 단리된 화합물 1-4는 1H- 및 13C-NMR 분석을 통하여 각각 (S)-(+)-2-cis-abscisic acid O-β-D-glucopyranosyl ester (화합물 1), 1-[4-O-β-D-glucopyranosyl]phenyl ethanone(piceoside, 화합물 2), β-sitosterol (화합물 3), 그리고 β-sitosteryl 3-O-β-D-glucopyranoside (화합물 4)로 동정되었다. 단리된 3종의 배당체 화합물(화합물 1, 2, 4)들은 본 연구에 의해 배로부터 처음 동정되었으며, 화합물 3은 추황배로부터 처음 동정되었다. 본 연구결과가 배 함유 성분연구는 물론 배의 기능성 해명 연구에도 추후 중요한 기초자료로 활용되길 기대한다. We isolated and identified antioxidants from acidic and neutral ethyl acetate fractions of the peel of pear (Pyrus pyrifolia N. cv. Chuhwangbae). We isolated 4 compounds from the methanol extract, by using 3 different types of column chromatography (Sephadex LH-20, silica gel, and octadecylsilane) and preparative HPLC. We identified the isolated compounds as (S)-(+)-2-cis-abscisic acid O-β-D-glucopyranosyl ester (compound 1), 1-[4-O-β-D-glucopyranosyl]phenyl ethanone (picroside, compound 2), β-sitosterol (compound 3), and β-sitosteryl 3-O-β-D-glucopyranoside (compound 4) by nuclear magnetic resonance analysis. We are the first to report the identification of compounds 1, 2, and 4 from pear.

고빌리루빈혈증을 동반한 자가면역성 간염 1례

서영범,김성욱,장재식,강혁주,이중현,윤병구,김욱년,이광헌,이구,유석동,양창헌,이정호,이영현,이창우,서정일 동국대학교 의학연구소 2000 東國醫學 Vol.7 No.-

자가면역성 간염은 대개 만성 경과를 가지며, 혈중 자가면역항체와 혈청 글로불린치의 상승, 그리고 조직학적으로 괴사 염증성 변화를 특징으로 하는 질환으로 아직 정확한 병인이 밝혀져 있지 않은 상태이다. 발병연령은 대개 젊은 영자(15-25세)에서 호발한다. 이 질환은 급성 간염의 임상경과를 보일 수 있으나, 심한 급성 간염이나 전격성 간염으로도 나타날 수 있는데, 이 경우 아주 나쁜 예후를 보인다고 한다. 치료는 자가면역성 간염 임상 경과의 다양성이나 병인, 병리기전의 불확실성에도 불구하고 대개 steroid 치료에 반응하는 것으로 알려져 있으며 대개 80%의 관해율을 나타내며 궁극적으로 간경변으로의 진행을 막을 수 있는 것으로 보인다. 저자들은 58세 남자에서 발생한 급성의 경과를 가지고 심한 황달을 동반한 자가면역성 간염을 경험하였기에 문헌고찰과 함께 보고하는 바이다. Autoimmune hepatitis (AIH) is a chronic necroinflammatory liver disorder of unknown cause associated with circulating autoantibodies and a high serum globulin level. The age of onset of AIH show a peak between the age of 15 and 25 years. AIH can develop and be manifested as acute hepatitis, but severe form of acute hepatitis or fulminant hepatic failure has a poor prognosis. Although AIH is likely to progress from chronic active hepatitis to cirrhosis, steroid therapy can control the disease activity, prolong survival, improve the quality of life , and defer liver transplantation. In the present report we describe a 58-year-old man who admitted because of progressive jaundice and fatigue. He was diagnosed with AIH from laboratory test result showing positivity for antinuclear antibodies, anti-smooth muscle antibodies, and negativity for hepatitis viral markers and from liver biopsy. Steroid therapy, oral administration of prednisolone, was effective in improving the liver function test. Following liver biopsy 6 months after onset shows markedly improved necroinflammatory activity.

2003년 국내 중증급성호흡기증후군 진료 현황 및 문제점 분석

이진수,김은실,정문현,백제중,정선화,안주희,최영화,이선희,고철우,김성범,김민자,박승철,기현균,송재훈,최상호,김양수,이상오,조용균,박영훈,정숙인,김연숙,이흥범,손창희,장성희,정희진,김우주 대한감염학회 2004 감염과 화학요법 Vol.36 No.3

목적 : 2002년 말 중국에서 SARS가 발생한 이후 국내에서도 2003년 10월까지 총 3명의 추정환자, 17명의 의심환자가 보고되었다. 향후 추가적인 SARS의 유행이 우려되는 상황에서, 그간의 SARS 환자 진료에 있어서의 실질적인 준비사항, 진료 현황 등에 대한 조사를 통해 문제점을 파악하여, 향후 더 나은 대비가 될 수 있도록 개선점을 제시하고자 하였다. 재료 및 방법 : SARS로 의심되는 환자를 진료 경험이 있는 병원의료진을 대상으로 2003년 10월에 설문조사를 실시하였다. 설문에는 SARS 환자 진료 시의 실질적인 조치, 진료 현황, 병실, 응급실 및 외래에서의 격리 시설과 준비사항, 보건당국의 관리와 지원에 관한 사항을 포함하였다. 결과 : 대상이 되는 22개 병원 중 17개(17/22, 77.2%) 병원이 설문에 응하였다. SARS 환자를 위한 격리실은 응급실, 외래, 일반병실 및 중환자실에서 각각 9개(9/17, 52.9%), 5개(5/17, 29.4%), 15개(15/16, 93.7%), 4개(4/16, 25%) 병원에서 음압처리가 되어있지 않은 일인실 혹은 다인실이 사용되었고, 1개(1/16, 6.3%) 병원에서만 일반병실에서 음압격리실이 운영되었다. 입원환자의 진찰 시 개인보호구의 착용은 거의 모든 의료기관에서 이루어졌다. 보건당국에서 SARS지정병원의 시설 등을 사전에 확인한 곳은 1곳(1/12, 8.3%)이였고, 14개 병원(14/15, 93.3%)에서는 보건당국에 의뢰한 검사결과를 통하 받지 못하였다. 결론 : 의료기관에서 SARS 환자용 격리실뿐만 아니라 기존의 격리실 설비 등이 미흡하였으며, 특히 중환자실 및 외래의 준비가 더욱 부족하였다. 보건당국의 의료기관에 대한 종합적인 지원이 부족하였고, 병원과의 원활한 연계가 잘 이루어지지 않았다. SARS 만이 아닌 격리를 필요로 하는 질환의 적절한 진료를 위해 향후 병원 시설의 정비와 정부차원에서의 보다 구체적이고 실질적인 대책마련이 필요하다. Background : There was an worldwide outbreak of the Severe Acute Respiratory Syndrome (SARS) originated from China in late 2002. During that period three cases of suspected SARS and 17 cases of probable SARS were reported in Korea. With the concerns about the reemergence of SARS-coV transmission, it is important to be prepared for any possibility. So, this study is aimed to analysis the past measures in managing SARS and propose the amendatory plans to improve the preparedness. Materials & Methods : Questionnaires were collected among clinicians with any experience in managing the probable or suspected SARS cases in Oct. 2003. 17 out of 22 hospitals responded to the questionnaire. The contents in the questionnaire were practical activities, personal equipments, response plans, isolation facilities in emergency centers, outpatient clinics, general wards and intensive care units, and relationship with the public health department. Results : The dedicated isolation rooms in emergency centers, outpatient clinics, general wards, and intensive care units were prepared in 9 (9/17, 52.9%), 5 (5/17, 29.4%), 15 (15/16, 93.7%), and 4 (4/16, 25.0%) hospitals, respectively. Except for one hospital that newly made negative pressure room for SARS, single or multi-bed rooms without airborne infection control were used in all the other hospitals. The personal precaution principles were kept quite well in general wards. Before the designation of SARS hospital by the public health department prior evalution to see if the hospital was suitable for managing SARS was conducted in only 1 (1/12, 8.3%) hospital. The results of laboratory diagnosis were reported back in 1 (1/15, 6.6%) hospital. Conclusions : The isolation facilities which can control airborne infection were almost deficient not only for SARS but also for other respiratory transmissible diseases. For the infection control of transmissible diseases including SARS, more investment is needed on medical facilities and comprehensive support from the public health department required.

Evaluating Corrosion Resistance of Additive-Manufactured Ti–6Al–4V Using Electrochemical Critical Localized Corrosion Temperature

Jae‑Bong Lee,Dong‑il Seo,Hyun Young Chang 대한금속·재료학회 2020 METALS AND MATERIALS International Vol.26 No.1

A new concept to evaluate the localized corrosion resistance of stacked Ti alloys such as additive-manufactured (AM)Ti–6Al–4V alloy is proposed. Crevice corrosion of subtractive-manufactured (SM) Ti–6Al–4V occurred on the surfacebeneath the crevice former, whereas localized corrosion of the AM alloy occurred in any vulnerable site irrespective of thecrevice assembly. The electrochemical critical localized corrosion temperature (E-CLCT) was measured to evaluate theresistance of AM Ti–6Al–4V alloys to localized corrosion. The results showed that the localized corrosion of AM Ti–6Al–4V was attributable to the anisotropy and microstructure that resulted from rapid cooling, which were completely differentfrom the anisotropy and microstructure of SM Ti–6Al–4V. The optimum applied potential of AM Ti–6Al–4V in 25 wt%NaCl aqueous solution was deduced. The E-CLCT provides a useful criterion for determining the resistance of AM Ti alloysto localized corrosion and for comparing their resistances.

내시경적 조직검사로 진단된 위 분선충증 1 예

이석호,이화영,이규택,강인구,최규완,백승운,이종균,이준혁,고광철,이종철,오영륜,현재근,이풍렬,김재준,채종일 대한소화기내시경학회 1999 Clinical Endoscopy Vol.19 No.2

Strongyloidiasis is a parasitic disease caused by Strongyloides stercoralis which exists in two forms : the free living and parasitic forms. It exists in warm, moist climate in areas where there is frequent fecal contamination of the soil. After cutaneous invasion by the filariform larvae, petechial hemorrage, pruritus, papular rashes, edema, and urticaria occur. Infection commonly occurs in the proximal intestine of the gastrointestinal (G-I) tract but may extend from the stomach to the anus. Once the worm is established in the small intestine, the physical findings may include epigastric tenderness to palpation. The mucosal biopsy is an inefficient way of making the diagnosis because the worm is found in the biopsy specimen in only 2% of patients. Gastric strongyloidiasis is rare. We experienced a case of gastric strongyloidiasis diagnosed by the endoscopic biopsy and serologic test for parasite specific IgG antibody by micro-ELISA.