일부 영세 도금사업장의 국소배기성능과 공기중 총크롬 , 6가 크롬 및 니켈농도와의 관계분석

박동욱,박두용,신용철,오세민,정규철 한국산업위생학회 1993 한국산업보건학회지 Vol.3 No.1

To evaluate efficiencies of the local exhaust systems installed in chromium and nickel electroplating tanks, specifications of each tank and general performances of the local exhaust systems were measured in 16 electroplating plants from July 3 to November 24, 1992. Airborne concentrations of total chromium, hexa-chromium and nickel were also measured. Most of the local exhaust systems installed in electroplating plants were inadequately designed. Average capture velocities of local exhaust systems in chromium and nickel tanks were 0.45 m/sec and 0.29 m/sec. Average slot velocities in chromium and nickel tanks were 7.30 m/sec and 2.87 m/sec respectively. Both average capture and slot velocities were in noncompliance with the standards recommended by American Conference of Governmental Industrial Hygienists (ACGIH) and National Institute for Occupational Safety and Health (NIOSH). Exhausted air volume was insufficient in all local exhaust systems surveyed. Worker exposure levels to total chromium, hexa-chromium and nickel were 43.0 ㎍/㎥, 1.7 ㎍/㎥ and 9.3 ㎍/㎥, which were below the Korean Standard and U.S. Occupational Health and Safety Administration (OHSA) Permissible Exposure Limit (PEL). However, Worker exposure level to hexa-chromium exceeded the NIOSH Recommended Exposure Limit(REL) of 1 ㎍/㎥. As the result of Scheffee's multiple comparions, worker exposure levels to all metals were significantly different between two groups by the management state of existing local exhaust systems (p$lt;0.05). However, Difference between a group with local exhaust systems which were poorly managed and another group without local exhaust system was satatistically non-significant.

인공판막 재대치험예에서의 판막실패의 양상

박영배,김유호,서정돈,최윤식,이영우,오병희,도문홍,최동주,전은석 대한내과학회 1987 대한내과학회지 Vol.32 No.3

In order to observe the aspects of prosthetic cardiac valve failure, we analyzed 26 cases of Redo operation among 1081 cases of valve replacemant performed from Jan. 1961. to July 1986. The results are as follows; 1) Crude Redo operation rate was 2.4%. 2) The most common cause or prosthetic cardiac valve failure was the primary tissue failure (73%) 8r the PVE was the 2nd (15.4%). 3) Mean valve implantation time was 47.7 months. Implantation time in the child group was shorter than in adult by 6.8 months, In the primary tissue failure group (19 cases) implantation time in the child was 42.8 months 8z in adult, 66.8 months. (P$lt;0.05) In conclusion, the durability of tissue valves was significantly decreased in the child age group because of increased propensity for calcification, so the preference of tissue valves especially in this age group should be reconsidered.

기관지내 전이암

김현수,이상수,오미희,이재갑,원구태,홍희승,용석중,신계철 대한내과학회 1991 대한내과학회지 Vol.40 No.4

The lung is the most common site of metastasis of extrapulmonary malignant tumor. According to past reports, metastatic cancer of the lung has been found in about 2% of all patients at autopsy. But these days, a diagnosis of endobronchial metastatic cancer utilizing bronchoscopy only is not easy. Thus we need other means of gathering more informaction, such as past history, discovery of other metastatic sites, and pathologic findings with special staining and electronmicroscope, especially in cases of poorly differentiated adenocarcinoma and epidermoid cancer, which are common types of primary lung cancer. We present 5 cases of endobronchial metastatic cancer. We found endobronchial metastatic cancer 2 cases of cervix cancer (epidermoid, adenocarcinoma), 1 case of colon cancer (adenocarcinoma), hypernephroma (renal cell carcinoma), and bladder cancer (transitional cell carcinoma). Since it was impossiole to diagnose the metastatic adenocarcinoma from the cervix only with lightmicroscopic findings, we could use past history and unusual radiologic and bronchoscopic findings which was thought to be the specific endoscopic finding of metastic endobronchial cancer. The interval between the diagnosis of the primary cancer and endobronchial metastatic cancer was 25.7 months. In the future, development of immunohistochemistry, monoclonal antibody, and molecular biologic techniques will give us diagnostic clue for differential diagnosis of metastatic endobronchial cancer from primary bronchogenic lung cancer.

급성 심근경색증 초기 진단에 latex 응집을 이용한 혈청 myoglobin 측정의 임상적 의의

박영배,서정돈,최윤식,이영우,오병희,손대원,임하진,김유우,박명희 대한내과학회 1987 대한내과학회지 Vol.32 No.2

We evaluated the diagnostic usefulness of latexagglutination test for elevated serum myoglobin as a screening test in the early phase of acute myocardial infarction and 21 patients with chest pain mimicking acute myocardial infarction were included in this study. Result was compared with serum myoglobin level measured by radioimmunoassay (RIA) in every case. The Following results were obtained: 1) When serum myoglobin levels measured by RIA below 85ng/㎖ were regarded as normal, this test showed sensitivity of 82%, specificity of 95%. 2) In latex-agglutionation test for elevated serum myoglobin, test results were interpreted as negative, weakly positive and positive. If we regard weakly positive tests as positive, sensitivity was 93% and specificity was 62%. In contrast, if we regard weakly positive tests as negative specificity rose to 100% while sensitivity reduced to 75%. 3) Agreement rate of both test was k=0.59. It is suggested that latex-agglutination test for elevated serum myoglobin is helpful in ruling out acute myocardial infarction when test result is negative, and that it can be used as a screening test in the early phase of acute myocardial infarction because of its rapidity and simplicity in performing the procedure.

승모판막 질환에서의 Doppler 심초음파도를 이용한 확장기 좌심방-좌심실 평균 압력차에 대한 연구

박영배,서정돈,이영우,김효수,도문흥,오병희 대한내과학회 1987 대한내과학회지 Vol.32 No.2

Diastolic LA and LV pressure gradient was determined with doppler echocardiography in 35 patients with mitral valvular heart disease and was compared with that determined with cardiac catheterization. In 23 patients who underwent mitral valvular replacement, pre and postoperative pressure gradients were observed, Correlation between pressure gradient and pressure half time was investigated with Doppler echocardiography. The results were as follows; 1) 1n total 35 patients with MVHD, mean ΔP in Doppler and cath were 15.8±6.3 (mean±S.D.) mmHg and 17.0±6.7mmHg, respectively, and the correlation coefficient was 0.91. 2) In 15 patients with pure MS, mean ΔP in Doppler and cath, were 15.5±6.1mmHg and 16.1±5.6mmHg, respectively, and the correlation coefficient was 0.90. 3) In 23 patients who underwent MVR, preop ΔP and postop Δ4P were 17.0±6.2mmHg and 2.2±0.9mmHg, respectively, and the difference was significant. 4) In 13 patients with Ionescu Shiley valve, ΔP and T were 2.1mmHgSl.lmmHg, and 110±50msec respectively. In 9 patients with St. Jude valve, ΔP and T1/2 were 2.3±0.7mmHg and 65±22msec, respectively, 5) The correlation coefficient between ΔP and T1/2 was 0.48 in total 35 MVHD and 0.57 in 15 pure MS. The correlation coefficient between ΔP divided by cardiac index and T1/2 f, was 0.63 in 15 pure MS. Therefore, Doppler echocardiography is a useful noninvasive diagnostic tool for measurement of the pressure gradient between LA and LV in MVHD, and can be used to assess the severity of preop, MVHD and postop. result and to follow up patients after operation.

리튬 2 차 전지의 양극재료인 스피넬 망간산화물의 용해와 용량감소

오승모,이종화,홍진규,장동훈 한국공업화학회 2001 공업화학 Vol.12 No.2

M-13 bacteriophage based structural color sensor for detecting antibiotics

Moon, J.S.,Park, M.,Kim, W.G.,Kim, C.,Hwang, J.,Seol, D.,Kim, C.S.,Sohn, J.R.,Chung, H.,Oh, J.W. Elsevier Sequoia 2017 Sensors and actuators. B Chemical Vol.240 No.-

Color sensor systems that exploit the advantages of M-13 bacteriophage have been shown to be potentially useful for detection of hazardous materials. The properties of M-13 bacteriophage can be systemically modified to impart target-specific selectivity and sensitivity using the phage display technique. Here, we describe a structural color-based sensor that utilizes genetically engineered M-13 bacteriophage to discriminate different types of antibiotics. An M-13 bacteriophage based structural color matrix was fabricated using a simple pulling technique by self-assembly of M-13 bacteriophage. When exposed to organic solvent, M-13 bacteriophage bundles promptly swell and promote distinct structural color change. Color sensors composed of M-13 bacteriophage genetically engineered to possess WHW peptide motifs clearly discriminated three different types of antibiotics, which was based on the color analysis of sensor using principal component analysis. Our sensing approach based on M-13 bacteriophage could be a promising sensor technique such as an environmental monitoring system.

ANGULAR MOMENTUM OF DWARF GALAXIES

Butler, Kirsty M.,Obreschkow, Danail,Oh, Se-Heon American Astronomical Society 2017 ASTROPHYSICAL JOURNAL LETTERS - Vol.834 No.1

<P>We present measurements of baryonic mass M-b and specific angular momentum (sAM) j(b) in 14 rotating dwarf Irregular (dIrr) galaxies from the LITTLE THINGS sample. These measurements, based on 21 cm kinematic data from the Very Large Array and stellar mass maps from the Spitzer Space Telescope, extend previous AM measurements by more than two orders of magnitude in M-b. The dwarf galaxies show systematically higher j(b) values than expected from the j(b) proportional to M-b(2/3) scaling of spiral galaxies, representative of a scale-free galaxy formation scenario. This offset can be explained by decreasing baryon mass fractions f(M) = M-b/M-dyn (where M-dyn is the dynamical mass) with decreasing M-b (for M-b < 10(11) M-circle dot 11). We find that the sAM of neutral atomic hydrogen (H I) alone is about 2.5 times higher than that of the stars. The M-j relation of H I is significantly steeper than that of the stars, as a direct consequence of the systematic variation of the H I fraction with M-b.</P>

Synthesis and broad-spectrum antiproliferative activity of diarylamides and diarylureas possessing 1,3,4-oxadiazole derivatives

Gamal El-Din, M.M.,El-Gamal, M.I.,Abdel-Maksoud, M.S.,Yoo, K.H.,Oh, C.H. Pergamon Press 2015 Bioorganic & medicinal chemistry letters Vol.25 No.8

A series of diarylamides and diarylureas possessing 1,3,4-oxadiazole scaffold was designed and synthesized. Their in vitro antiproliferative activities were tested against a panel of 58 cell lines of nine different cancer types at the NCI, and compared with Sorafenib as a reference compound. Most of the compounds showed strong and broad-spectrum antiproliferative activities. The diarylurea compound 2g possessing 4-chloro-3-(trifluoromethyl)phenyl terminal moiety showed the highest mean % inhibition value of about 100% over the 58-cell line panel at 10μM concentration. Also compounds 2h, 2l, 2m exhibited mean % inhibition over 90% at 10μM concentration. The IC<SUB>50</SUB> value of compound 2b over SNB-75 CNS cancer cell line was 0.65μM. Compound 2h also exerted submicromolar IC<SUB>50</SUB> values of 0.67, 0.80, and 0.87μM against PC-3 prostate cancer cell line, HCT-116 colon cancer cell line, and ACHN renal cancer cell line, respectively. Compound 2h showed comparable efficacy to Sorafenib.

Effects of Inorganic Aerosols on the Gas-Phase Reactions of the Hydroxyl Radical with Selected Aliphatic Alkanes

Oh, Sewon,Andino, Jean M. 한국대기환경학회 2003 한국대기환경학회지 Vol.19 No.E3

Effects of inorganic. aerosols on the kinetics of the hydroxyl radical reactions with selected aliphatic alkanes have been investigated using the relative rate technique. The relative rates in the absence and presence of aerosols were determined for n-butane, n-pentane, n-hexane, n-octane, and n-decane. P-xylene was used as a reference compound. Inorganic aerosols including (NH₄)S0₄. NH₄NO₃, and NaCI aerosols at two different aerosol concentrations that are typical of polluted urban conditions were tested. Total surface areas of aerosols were 1400 (Condition I) and 3400㎛²cm (Condition II). Significant changes in the relative rates in the presence of the inorganic aerosols were not observed for the n-butane/· OH, n-pentane/·OH, n-hexane/·OH. n-octane/·OH, and n-decane/·OH reactions versus p-xylene/·OH reaction. These results suggest that the promoting effects depend on the semiconducting property of the aerosols and the nature of the organic compounds.