Investigation of the electrical and optical properties of InAs/InGaAs dot in a well solar cell

Lee, S.H.,Han, I.S.,Sohn, C.W.,Jo, H.J.,Kim, J.S.,Lee, S.J.,Noh, S.K.,Kim, J.O. Elsevier 2015 Current Applied Physics Vol.15 No.11

The electroreflectance (ER) and current-voltage (J-V) of InAs/InGaAs dots in a well (DWELL) solar cell (SC) were measured to examine the optical and electrical properties. To investigate the carrier capturing and escaping effects in the quantum dot (QD) states the above and below optical biases of the GaAs band gap were used. In the reverse bias region of the J-V curve, the tunneling effect in the QD states was observed at low temperature. The ideality factors (n) were calculated from the J-V curves taken from various optical bias intensities (I<SUB>ex</SUB>). The changes in the ideality factor (n) and short circuit current (J<SUB>SC</SUB>) were attributed mainly to carrier capture at low temperature, whereas the carrier escaping effect was dominant at room temperature. ER measurements revealed a decrease in the junction electric field (F<SUB>J</SUB>) due to the photovoltaic effect, which was independent of the optical bias source at the same temperature. At low temperature, the reduction of photovoltaic effect could be explained by the enhancement carrier capturing effect due to the strong carrier confinement in QDs.

¹³¹I-labeled chitosan hydrogels for radioembolization: A preclinical study in small animals

Hwang, H.,Kim, K.I.,Kwon, J.,Kim, B.S.,Jeong, H.S.,Jang, S.J.,Oh, P.S.,Park, H.S.,Lim, S.T.,Sohn, M.H.,Jeong, H.J. Pergamon Press 2017 Nuclear medicine and biology Vol.52 No.-

<P>Advances in knowledge: Transarterial embolization is a conceivable treatment option for patients with inoperable liver cancer to mitigate the disease progression. Recently, we have developed chitosan-based hydrogel microparticles. In the present study, the hydrogel microparticles were radiolabeled with I-131 for treatment of liver cancer. Our results demonstrated that a hepatic arterial injection of I-125 -labeled Chi resulted in substantial liver accumulation, which was accompanied by virtually no extrahepatic deposition. The results of the present study also showed that administration of I-131 Chi markedly suppressed tumor growth, compared to controls and to animals receiving unlabeled Chi. I-131 -labeled chitosan hydrogel microparticles represent a new therapeutic approach for treatment of liver cancer. (C) 2017 Elsevier Inc. All rights reserved.</P>

조선업 용접공진폐증에서 용접 흄 폭로력에 따른 방사선소견과 폐기능검사소견의 비교연구

손혜숙,김성준,김정호,이채언,정귀원,조규일,전진호,배기택 大韓産業醫學會 1991 대한직업환경의학회지 Vol.3 No.2

By the state of exposure to welding fume, the radiographic findings of 31 shipyard welders diagnosed as pneumoconiosis and pulmonary function were evaluated. Subjects were divided into three groups by the state of exposure to welding fumes i.e. Group Ⅰ- complete job replacement after detection of pneumoconiosis. Group Ⅱ- incomplete job replacement. Group Ⅲ- no job replacement. The results were as follows ; 1. Radiographic findings had a difference among three groups- GroupⅠ(complete job replacement). Group Ⅱ (incomplete job replacement). Group Ⅲ (no job replacement)(P<0.05), but pulmonary function had no difference. 2. Pulmonary function was not significantly different in diagnostic radiographic findings-normal, suspected pnemoconiosis, simple pnemoconiosis. 3. VC and FVC decreased with increasing age and total exposure duration to welding fumes. And FEV₁decreased with increasing exposure duration. 4. In welders exposed to welding fumes over 20 years, all performed pulmonary functions (VC, FVC, FEV, MMF, FEF75%) recorded by observed/predicted ratio were less than 80%. Based on the above results, the radiographic abnormal findings improved if job replaces but pulmonary function was not significantly different among three groups- GroupⅠ, Group Ⅱ, Group Ⅲ. So it is thought that job replacement and continuous observation on radiographic findings and pulmonary function is useful for control of pneumoconiosis of shipyard welders.

Protective effect of EC-18, a synthetic monoacetyldiglyceride on lung inflammation in a murine model induced by cigarette smoke and lipopolysaccharide

Shin, I.S.,Ahn, K.S.,Shin, N.R.,Lee, H.J.,Ryu, H.W.,Kim, J.W.,Sohn, K.Y.,Kim, H.J.,Han, Y.H.,Oh, S.R. Elsevier Science 2016 INTERNATIONAL IMMUNOPHARMACOLOGY Vol.30 No.-

The antler of Sika deer (Cervus nippon Temminck) has been used a natural medicine in Korea, China and Japan, and a monoacetyldiaglyceride (1-palmitoyl-2-linoleoyl-3-acetylglycerol, PLAG) was found in the antler of Sika deer as a constituent for immunomodulation. In this study, we investigated protective effects of EC-18 (a synthetic copy of PLAG) on inflammatory responses using a cigarette smoke with lipopolysaccharide (LPS)-induced airway inflammation model. Mice were exposed to cigarette smoke for 1h per day for 3days. Ten micrograms of LPS dissolved in 50μL of PBS was administered intra nasally 1h after the final cigarette smoke exposure. EC-18 was administered by oral gavage at doses of 30 and 60mg/kg for 3days. EC-18 significantly reduced the number of neutrophils, reactive oxygen species production, cytokines and elastase activity in bronchoalveolar lavage fluid (BALF) compared with the cigarette smoke and LPS induced mice. Histologically, EC-18 attenuated airway inflammation with a reduction in myeloperoxidase expression in lung tissue. Additionally, EC-18 inhibited the phosphorylation of NF-κB and IκB induced by cigarette smoke and LPS exposure. Our results show that EC-18 effectively suppresses neutrophilic inflammation induced by cigarette smoke and LPS exposure. In conclusion, this study suggests that EC-18 has therapeutic potential for the treatment of chronic obstructive pulmonary disease.

CH₄ mixing ratios at microbar pressure levels of Jupiter as constrained by 3-micron ISO data

Kim, S.J.,Sim, C.K.,Sohn, M.R.,Moses, J.I. Academic Press 2014 Icarus Vol.237 No.-

Infrared Space Observatory (ISO) data of Jupiter are revisited in order to derive CH<SUB>4</SUB> mixing ratios at microbar pressures in the atmosphere. We utilize the most updated radiative transfer programs to construct a 3-μm emission model of CH<SUB>4</SUB> to be compared with the ISO data. From the model-data comparisons, we derive the high-altitude CH<SUB>4</SUB> mixing ratios, which turn out to be at least 10 times smaller than the microbar CH<SUB>4</SUB> mixing ratios assumed in the Galileo probe analysis (Seiff, A. et al., 1998. Thermal structure of Jupiter's atmosphere near the edge of a 5-μm hot spot in the north equatorial belt. J. Geophys. Res., 103, 22857-22889. doi:10.1029/98JE01766), but which are approximately consistent with ultraviolet airglow observations and with available photochemical models that assume relatively weak atmospheric mixing. We also compare the derived CH<SUB>4</SUB> profile with results from other investigations reported in literature and discuss the implications with respect to photochemistry and vertical transport in the stratosphere of Jupiter.

A Case of Type IIa Early Gastric Cancer Developed in Pernicious Anemia

Ahn, M.-J Korean Academy of Medical Science 1998 Journal of Korean medical science Vol.13 No.1

Atmospheric mercury at an urban station in Korea across three decades

Kim, K.H.,Brown, R.J.C.,Kwon, E.,Kim, I.S.,Sohn, J.R. Pergamon Press ; Elsevier [distribution] 2016 Atmospheric environment Vol.131 No.-

<P>The concentrations of total gaseous mercury (TGM) over three decades (1987-2013) were monitored at an urban station at Yan San (YS), Seoul, Korea. The results were examined by considering the prominent patterns in observed concentrations during periods where data were available: [1] period I (P1) = Sep. 1987 to Oct. 1988, [2] period II (P2) = Sep. 1999 to Jul. 2000, [3] period III (P3) = Jan. 2004 to Dec. 2011, and [4] period IV (P4) = Jan. 2012 to Dec. 2013. The data in this study indicate that the concentrations of TGM decreased abruptly from P1 (similar to 15 ng m(-3)) to P2 (similar to 5 ng m(-3)). Then, during the most of P3 (i.e., from 2004 to 2011), the annual mean values were nearly constant and their concentrations were in the range 3 -4 ng m(-3). The mean values then decreased to similar to 2 ng m(-3) in P4. Hg levels in the late 1980s reflect the dominant role of major man-made source processes (e.g., unabated combustion of much dirtier fossil fuels). Unlike the earlier Hg monitoring data, the concentrations of Hg in recent periods could be attributed to a shift from coal to kerosene and natural gas in urban areas and to more stringent emissions regulations and cleaner fuels. It is unclear currently whether the latest and lowest concentrations measured during in P4 will be maintained during upcoming years, although they seem to reflect the direct impact of air quality control efforts since the 1980s. (C) 2016 Elsevier Ltd. All rights reserved.</P>

Effect of Filament Configuration on Critical Current Density of Bi2212/Ag Wires With Low Ag Ratio

Kim, S.-C.,Ha, D.-W.,Oh, S.-S.,Han, I.-Y.,Oh, J.-G.,Sohn, H.-S. IEEE 2008 IEEE transactions on applied superconductivity Vol.18 No.2

<P>Effect of filament configuration and heat treatment of Bi2212/Ag round wire with low Ag ratio on the engineering critical current density (J<SUB>e</SUB>) was reported. We have fabricated 557, 85 7, and 121 7 wires with different Ag ratio and evaluated at various wire diameters. We have also changed the parameters of heat treatment. The effects of maximum process temperature (T<SUB>max</SUB>)and soaking time at T<SUB>max</SUB> and average filament diameter on the J<SUB>e</SUB> were also studied. 121 7 wire of 0.95 mm diameter heat-treated at showed J<SUB>e</SUB> of 858mm<SUP>2</SUP> at 4.2K, 0 T.</P>

조선업 용접공진폐증에서 용접 흄 폭로력에 따른 방사선 소견의 경시적 변화양상

손혜숙,이종태,신해림,이채언,배기택,박형종,김용완,윤임중,Sohn, H.S.,Lee, J.T.,Shin, H.R.,Lee, C.U.,Pae, K.T.,Park, H.J.,Kim, Y.W.,Yun, I.G. 대한예방의학회 1989 예방의학회지 Vol.22 No.3

27 shipyard welders were diagnosed as pneumoconiosis and suspected pneumoconiosis(1976-1988) by chest radiographs and were observed over three years. 27 welders were divided into three groups by the state of exposure to welding fume i.e. cessation, decresase or continuity of exposure. And we observed the changing pattern of the chest radiographs of 27 welders with the passage of time. The results were as follows; 1. Grour I (ceased exposure to welding fume) were 10 cases(3 cases: suspected pneumoconiosis,7 cases: pneumoconiosis). Chest radiographs of all cases were improved. The shape and size of small opacities was improved in 6 cases(85.7%) and did not changed in 1 case(14.3%) out of 7 pneumoconiosis welders. 2. Group II (decreased exposure to welding fume) were S cases(2 cases: suspected pneumoconiosis, 3 cases: pneumoconiosis). Chest radiographs were progressed in 2 cases(40%), did not changed in 1 case(20%), were improved in 2 cases(40%) out of 5 cases. The shape and size of small opacities was progressed in 1 case(33.3%) and was improved in 2 cases(66.7%) out of 3 pneumoconiosis welders. 3. Group III(continued expoxsure to welding fume) were 12 cases(1 case: suspected pneumoconiosis, 11 cases: pneumoconiosis). Chest radiographs were progressed in 9 cases(75%), did not changed in 3 cases(25%) out of 12 cases. The shape and size of small opacities was progressed in 1 case(9.1%) and did not changed in 10 cases(90.9%) out of 11 pneumoconiosis welders. 4. The average duration for development into suspected pneumoconiosis was 6.6 years and for progression of each one category after that was 2.2 years(p<0.01). The radiological appearance of pneumoconiosis had disappeared or decreased after cessation of exposure to the welding fume. So that, early detection and control e.g., change of department of pneumoconiosis of welders by screening program will be important for medical surveillance of welders.

옥수수 - 대두박 사료내 미생물 Phytase 의 첨가가 브로일러의 생산능력에 미치는 영향

손광수,권관,권찬호,장재익,주종철,유문일,최양웅 한국축산학회 1999 한국축산학회지 Vol.41 No.5

This experiment was conducted to evaluate the effects of a domestic phytase originated from bacterial source on performance of starter and Bower broiler chicks. It was basically designed to meet NRC requirement for the contents of calcium and phosphorus when the contents of Ca and P in the feeds were met to 100%(Control; C) and 80%(P0) of the NRC requirement. Three different bacterial phytase(0, 300, 500PU) were supplemented to basal diet and compared it's effect on growth performance, nutritional digestibility, fecal N and P excretion, tibial Ca and P content. A total 200 broiler chicks were assigned to 4 treatments with 5 replications per treatment, 10 chicks of each replication. The weight gain(1,581.6g) in control treatment(C) was slightly higher than that of P0(1,557.7g). Although phytase treatments(P300 and P500) tended to show higher weight gain as compared to treatments without phytase, there were no significant differences among the treatments. No differences were observed among dietary treatments for feed efficiency although broiler chicks fed control diet (1.94) tended to show slightly better feed efficiency than those fed P0 diet(1.99). The excretion of P per kg weight gain tended to be decreased by 17% when 300PU of bacterial phytase was fed to starter and by 10% when 500PU was fed to Bower. However, there were no statistical significances among the treatments. It was concluded that the addition of phytase had neither affects in improving of utilization efficiencies of dry matter, crude protein, and crude fat, nor efficiencies of Ca and P. The supplemental of phytase at the level of 500 ppm for both stages of broiler chick diets was assumed to appropriate.