담도 및 췌장 악성종양에서의 CAl9-9의 진단적 가치에 대한 평가

명승재,최승목,김은옥,최호순,이성구,김명환,민영일,류진숙 大韓消化器病學會 1995 大韓消化器病學會誌 Vol.27 No.3

Nanogenerators: Fully Rollable Transparent Nanogenerators Based on Graphene Electrodes (Adv. Mater. 19/2010)

Choi, Dukhyun,Choi, Min-Yeol,Choi, Won Mook,Shin, Hyeon-Jin,Park, Hyun-Kyu,Seo, Ju-Seok,Park, Jongbong,Yoon, Seon-Mi,Chae, Seung Jin,Lee, Young Hee,Kim, Sang-Woo,Choi, Jae-Young,Lee, Sang Yoon,Kim, Jo WILEY-VCH Verlag 2010 ADVANCED MATERIALS Vol.22 No.19

<B>Graphic Abstract</B> <P>The cover shows an image of fully rollable transparent nanogenerators synthesized using chemical vapor deposition grown large-scale graphene sheets as transparent electrodes and piezoelectric ZnO nanorod arrays. Sang-Woo Kim, Jae-Young Choi, and co-workers report on p. 2187 the electrical and structural stability of the nanogenerators, with excellent charge scavenging performance under external mechanical loads such as bending and rolling. This study shows that graphene-based nanogenerators are very promising for self-powered rollable transparent device applications. <img src='wiley_img_2010/09359648-2010-22-19-ADMA201090066-content.gif' alt='wiley_img_2010/09359648-2010-22-19-ADMA201090066-content'> </P>

다발성 말초신경병증의 조기진단 : 적외선 체열촬영검사와 전류지각역치검사의 조합진단 Combination Diagnosis Using by Digital Infrared Thermogram and Current Perception Threshold

이삼규,김재형,최인성,이소영,한재영,조성렬,김재휴,노성만,정민영,정동진,김현성 全南大醫大 2001 전남의대학술지 Vol.37 No.3

소음 노출 남성 근로자에서의 청력저하와 혈청 마그네슘의 관련성

박완섭,이종영,정상재,유재영,최태성,홍성철,노성찬 大韓産業醫學會 2000 대한직업환경의학회지 Vol.12 No.1

목적 : 본 연구는 소음에 노출된 남자 근로자를 대상으로 장기간 소음 폭로가 혈청 마그네슘의 농도와 관련이 있는지를 검정하고 이러한 혈청 마그네슘의 농도가 또한 청력저하와 관련이 있는지를 파악하기 위하여 수행되었다. 방법 : 소음에 노출되는 178명의 연구대상자를 청력저하의 정도에 따라 세 그룹으로 분류하고, 구조화된 설문, 신체계측, 혈액검사 등으로 청력저하에 대한 감수성 요인과 혈청 마그네슘 등을 수집하고 측정하였으며, 대상자들의 청력 역치를 측정하기 위하여 청력검사를 실시하였다. 결과 : 본 연구의 결과를 요약하면 다음과 같다. 첫재, 청력저하에 관련된 개인의 감수성 인자라고 알려진 변수인 흡연유무, 나이, 혈압, 헤마토크리트, 콜레스테롤, 혈당 중에서 나이, 이완기 혈압이 단순분석에서 세 그룹간에 차이가 있었고(p〈0.05), 혈청 마그네슘의 농도 또한 세 그룹간에 통계적으로 유의한 차이가 있었으며(p〈0.05) 청력저하가 심할수록 혈청 마그네슘 농도는 낮아지는 경향을 보였다. 둘째, 그룹간의 소음 노출력은 차이가 있었지만 (p〈0.05) 청력보호구 착용상태에는 유의한 차이가 없었다. 셋째, 혈청 마그네슘 농도에 영향을 줄 수 있는 변수인 소음 노출 기간, 마그네슘 함량이 많은 음식의 섭취정도, 스트레스 수준 중에서 소음 노출기간이 혈청 마그네슘 농도와 유의한 상관관계를 보였고(p〈0.05) 노출기간이 길수록 마그네슘의 혈청농도는 낮아지는 경향을 나타내었다. 넷째, 주파수별로 청력저하와 관련된 감수성 요인들에 대한 다중회귀분석 결과 주파수 1,000 Hz에서는 연령이 좌,우측 귀 모두에서 유의한 변수로 채택되었으며 (p〈0.05), 연령이 증가할수록 청력저하가 심해지는 경향을 보였고, 주파수 4,000 Hz에서는 확장기 혈압, 소음 노출 기간, 혈청 마그네슘 등이 청력저하에 대한 감수성 요인으로 채택되었으며(p(0.05), 이완기 혈압이 높을수록, 소음노출 기간이 길수록, 혈청 마그네슘의 농도가 낮을수록 청력저하가 심해지는 것으로 나타났다. Objectivea : This study was conducted to investigate that the chronic noise exposure is associated with decreased serum magnesium concentrations and evaluate whether decreased serum magnesium is associated with noise induced hearing loss. Methods : One hundred seventy-eight male workers exposed to noise were selected and classified three groups by the degree of hearing loss. Hearing threshold levels were less than 30 dB at 1,000 Hz or less than 40 dB at 4,000 Hz In group I, more than 30 dB at 1,000 Hz or more than 40 dB at 4,000 Hz and 15 dB and less of pure tone average[PTA : (500 Hz+l,000 Hz+2,000 Hz)/3] in group II, more than 30 dB at 1,000 Hz or more than 40 dB at 4,000 Hz and over 15 dB of PTA in group III. Results : Serum magnesium concentrations were 2.42±0.26 mg/dl in group 1, 2.35±0.23 mg/dl in group n , 2.26±0.24 mg/dl in group II, respectively and significantly differ-ent between group I and group III (p〈0.01). It was negatively correlated with duration of the noise exposure as correlation coefficient (r) of -0.194 (p(0.05) . Analysis of the multipleregression on hearing threshold levels showed that serum magnesium, diastolic blood pres-sure, duration of the noise exposure were statistically significant at 4,000 Hz (p(0.05) . While only age was statistically significant at 7,000 Hz (p(0.05) . Conclusions : These results suggest that chronic noise exposure may induces decreasein serum magnesium concentrations and that its decreased concentration is related with noise induced hearing loss.

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.

열공형과 비열공형 피질하 혈관성 치매에서 위험인자의 차이에 관한 비교 연구

배희준,정지향,유경호,나덕렬,김상윤,최경규,양동원,손의주,이상도,김재우,박경원,김응규,이재홍,박미영,한일우,함동석,최문성,하충건,최성혜,이애영,이병철,한설희 대한치매학회 2003 Dementia and Neurocognitive Disorders Vol.2 No.2

Backgrounds and Objectives: Vascular dementia is a group of dementing disoders arising from various stroke syndrome. Among these. subcortical ischemic vascular dementia (SIVD) is regarded as a relatively distinct clinical entity. However, MRI patterns of SIVD are not homogenous. In some patients, lacunes are dominant, and in others, subcortical white matter changes are. This study was designed to compare risk factor profiles between SIVD with and without multiple lacunes. Methods: We divided 47 subjects (22 males, mean age. 68 years) recruited from VADAPET (Multicenter Trial For Evaluation Of The Changes In the PET Images Of Subcortical Vascular Dementia Patient) study into two groups one with more than 5 lacunes in deep gray matter (lacune group) and the other with 5 or less(non-lacune group) Clinical characteristics and laboratory findings of two groups were compared. Results: Nineteen of 47 patients (40%) belonged to the lacune group. The lacune and non-lacune groups d d not differ in the following variables: age, hypertension, diabetes mellitus, hyperlipidemia heart disease, history of stroke or TIA, history of trauma or major surgery, family history of hypertension stroke, or dementia, age at diagnosis of dementia, body mass index, white blood cell count, ESR, CRP, fibrinogen, hemoglobin A1C, total cholesterol. LDL cholesterol creatinine, proteinuria, glucosuria, and microhematuria. However, male sex, smoking alcohol. hemoglobin, and HDL cholesterol were possibly associated more with lacune group SIVD than with non-lacune group (p<0 1) Multivariate analyses revealed that smoking, hemoglobin, and HDL cholesterol were independent predictors of SIVD with multiple lacunes Conclusion: Our study suggests that SIVD with multiple lacunes may be significantly different in smoking habits hemoglobin, and HDL cholesterol from SIVD without multiple lacunes.

분산 멀티미디어 시스템의 성능 분석 기법

최항묵,성재철,김상균 인제대학교기초과학연구소 1999 자연과학 Vol.3 No.-

네트워크를 기반으로 하는 분산 시스템, 영상 회의 시스템, 병렬처리 시스템등을 대상으로 성능분석에 사용된 성능 평가 인자들과 성능평가 기법들에 대하여 고찰하고자 한다. 이는 현재 개발 중인 의료 영상 회의 시스템(MICS)의 성능을 평가하기 위하여 이와 유사한 시스템들을 고찰하고, 시스템의 성능평가를 위해 선택, 사용된 성능 평가 항목 및 평가 방법에 대하여 검토하여 적합한 성능평가 항목 및 성능평가 기법을 제시하기 위함이다. In this paper, I would like to investigate about "performance evaluation techniques" and "performance evaluation factors" used in performance analysis for systems in network based distributed system, image conference system and parallel processing systems. The aim is to propose profitable performance evaluation factors and performance evaluation techniques. For this, I went through similar systems to evaluation factors and performance evaluation techniques. For this, I went through similar systems to evaluate the performance of MICS(Medical Image Conference system)which is still being developed and worked out performance evaluation factors and evaluation methods to evaluate performance of system.

Consideration of Diluents Selection and Input Amounts of the Hunter Process for Tantalum Production

Jae‑Jin Sim,Sang‑Hoon Choi,Yong‑Kwan Lee,Sung Gue Heo,Taek‑Soo Kim,Seok‑Jun Seo,Kyoung‑Tae Park 대한금속·재료학회 2021 METALS AND MATERIALS International Vol.27 No.7

Tantalum (Ta) is a heavy refractory metal with an atomic weight of 180.95 g/mol, a density of 16.6 g/cm3, and a high meltingpoint of 3017 °C. With its refractory characteristics, it shows excellent chemical and physical stability as well as corrosionand heat resistance at elevated temperatures. The demand for Ta metal and related compounds is increasing with the expansionof the electronics and chemical industries. The Hunter process was proven to be effective in producing Ta powder in1953. Hunter proposed a method in which potassium heptafluorotantalate (K2TaF7) was reduced by sodium (Na). Thus far,this process has been the primary commercial method to produce Ta powder. In this study, quantitative differences wereanalyzed for diluent selection. Additionally, consideration was given to changes in the caloric value depending on the inputamount of diluents. Finally, the optimum material input and the properties of the prepared Ta were analyzed. Stoichiometricratios of K2TaF7(1 mol), NaCl (6.2–6.7 mol), Na (5–7 mol) were weighed, to perform a metallothermic reduction reaction. After the reaction, the tantalum powder was recovered and the flush process was carried out. After that, it was dried in avacuum atmosphere. Physical properties such as oxygen concentration, PSA, ICP-OES, and XRD of powder were conductedto evaluate the characteristics of Ta powder that was finally manufactured.

폴리(아미드-이미드-이미드)의 합성 및 그 특성에 관한 연구

최승재,서경범 단국대학교 1998 論文集 Vol.32 No.-

Polyimides which is among the class of heterocyclic polymers, have remarkable high temperature resistance, tensile strength, toughness, etc. However, fabrication and processing of imide polymers have been limited because fully cured imide polymers are generally infusible and insoluble in most solvents. A number of methods have been used to overcome intractability while maintaining reasonably high temperature characteristics. To attain these thermoplasticity, polyimides have been modified either through the addition of a side chain or through introduction of flexible, non-symmertrical and thermally stable linkages to the backbone. Among these modifications, the combination of amide and imide groups which resulted in poly(amide-imide)s [PAI] imparts flexibility, elongation and toughness. So, a new structure of an anhydride-acid chloride was designed for novel poly (amide-imide-imide)s. Successfully, we prepared a novel anhydride-acid chlorie containing imide group as a monomer form L-glutamic acid and trimellitic acid anhydride [TMA]. The resulting poly(amide-imide-imide)s were synthesized by polycondensation of new monomer and the various diamines. It is shown that the synthesized poly(amide-imide-imide)s overcome problems accociated with polymide as well as provide higher thermal stabilities due to high content of imide group in the polymers The chemistry and properties of the resulting polymers will be discussed.

플라스틱의 熱分解에 관한 硏究

崔乘載 단국대학교 1977 論文集 Vol.11 No.-

플라스틱의 分解는 熱分解, 光 또는 放射線에 의한 分解, 酸化 혹은 化學的 分解方法 등에 의하여 無秩序한 分解와 連銷解重合(逆成長反應)으로 두가지 형태로 分解가 이루어진다. 本硏究實驗에서는 熱重量分析(T.G.A)과 示差熱分析(D.T.A)裝置로 플라스틱의 熱分解를 溫度上昇에 따른 構造의 變化, 分解反應機構 및 生成物質 등을 考察하고 完全히 熱分解되어 炭化된 플라스틱의 再活用 可能性을 硏究檢討하여 본 結果 플라스틱에 包含하고 있는 휘발성 物質은 250℃∼350℃에서 거의 分解하여 重量減少率이 급격하였고 350℃∼430℃ 사이에서는 不胞和炭化水素로 存在하였으나 500℃以上에서는 거의 炭素構造로 轉換되었다. 그리고 플라스틱의 폐품을 炭化活性化하여 特殊吸着劑나 탈취제 및 脫色劑로 再活用할 수 있을 것으로 보였다. Degradation of plastics is formed two types by pyrolysis, light, radioactive ray, oxidation or chemical degradation. One is random degradation, another is chain depolymerization. In this study, the structural change, the mechanism of degradation and the products are observed in accordance with increased temperature by the thermogravimetric analysis (T.G.A) and differential thermal analysis (D.T.A). The reapplied feasibility of carbonized plastics, pyrolyzed completely, have been studied and the conclution of this study are as follows. (1) The volatile matter in poly vinyl chloride and polyethylene is decomposed practically and evaporated at 250˚C-350˚C and the decreased rate of gravity showes rapidly. (2) Poly vinyl chloride remain unsaturated hydrocarbon between 350˚C and 430˚C. However, it is decomposed completely and formed carbon structure at least 500˚C. (3) The waste plastics by degradation, can apply to the particular adsorbent, deodorant or discharge by carbonization and activation.