Improvement of Korea Local Radar Processing System (KLRPS) for data assimilation and its impact on very short range forecast

Kang-Deuk Ahn,Yo-Han Cho,Sung-Hwa Jung,GyuWon Lee,Yong Hee Lee 한국기상학회 2011 한국기상학회 학술대회 논문집 Vol.2011 No.10-2

Suppression of chemically-induced liver tumors by castration or estradiol-3-benzoate treatment in F344 rats.

Kang, Jin Seok,Ahn, Byeongwoo,Kim, Chuel Kyu,Han, Beom Seok,Che, Jeong-Hwan,Kim, Seyl,Jang, Dong Deuk,Yang, Ki-Hwa National Hellenic Research Foundation 2005 Oncology reports Vol.14 No.2

<P>Epidemiological data reveal that the incidence of liver cancer is markedly higher in men than women. To clarify the mechanism responsible for the induction of higher incidence of liver tumors in male animals, we investigated the modifying effect of sex hormones in diethylnitrosamine (DEN)-induced rat hepatocarcinogenesis. F344 male rats (n=120) were divided into two experiments, experiment I (Exp I) and experiment II (Exp II). In each experiment, 60 rats were randomly allocated into four groups. The mini-osmotic pumps containing doses of 47.5 mg (Exp I) or 23.75 mg (Exp II) of DEN were inserted into the abdominal cavity of each animal to initiate liver carcinogenesis. Animals in group 2 were castrated one week prior to DEN treatment, and animals in groups 3 and 4 were treated with 1 or 10 microg of estradiol-3-benzoate (EB), respectively, one week prior to DEN treatment. Animals in group 1 were treated with DEN alone and sham-operated at the same time. All animals were sacrificed 26 weeks after DEN treatment. In Exp I, liver tumor incidence of group 3 decreased significantly compared with that of group 1 (p<0.05), and tumor multiplicities of groups 2, 3 and 4 were decreased significantly compared to that of group 1 (p<0.01). In Exp II, tumor incidence of group 3 was significantly different (p<0.05) when compared to that of group 1. Immunohistochemical expression of ERalpha was shown in normal appearing cells, but not in tumor cells. Western blot analysis confirmed that ERalpha expression was higher in normal liver tissue compared to tumor tissues. Taken together, we conclude that castration or EB treatment has an inhibitory effect in DEN-induced hepatocarcinogenesis in F344 rats. The reason for ERalpha loss in tumor cells should be further elucidated.</P>

Regulation of IGFBP-2 expression during fasting

Kang, Hye ,Suk,Kim, Mi-Young,Kim, Seung-Jae,Lee, Jae-Ho,Kim, Yong-Deuk,Seo, Young-Kyo,Bae, Jae-Hoon,Oh, Goo-Taeg,Song, Dae-Kyu,Ahn, Yong-Ho,Im, Seung-Soon Portland Press Ltd. 2015 Biochemical journal Vol.467 No.3

<▼1><P>Insulin-like growth factor (IGF)-binding protein-2 (IGFBP-2), one of the most abundant circulating IGFBPs, is known to attenuate the biological action of IGF-1. Although the effect of IGFBP-2 in preventing metabolic disorders is well known, its regulatory mechanism remains unclear. In the present study, we demonstrated the transcriptional regulation of the <I>Igfbp-2</I> gene by peroxisome-proliferator-activated receptor (PPAR) α in the liver. During fasting, both <I>Igfbp-2</I> and <I>PPARα</I> expression levels were increased. Wy14643, a selective PPARα agonist, significantly induced <I>Igfbp-2</I> gene expression in primary cultured hepatocytes. However, <I>Igfbp-2</I> gene expression in <I>Pparα</I> null mice was not affected by fasting or Wy14643. In addition, through transient transfection and chromatin immunoprecipitation assay in fasted livers, we determined that PPARα bound to the putative PPAR-responsive element between −511 bp and −499 bp on the <I>Igfbp-2</I> gene promoter, indicating that the <I>Igfbp-2</I> gene transcription is activated directly by PPARα. To explore the role of PPARα in IGF-1 signalling, we treated primary cultured hepatocytes with Wy14643 and observed a decrease in the number of IGF-1 receptors (IGF-1Rs) and in Akt phosphorylation. No inhibition was observed in the hepatocytes isolated from <I>Pparα</I> null mice. These results suggest that PPARα controls IGF-1 signalling through the up-regulation of hepatic <I>Igfbp-2</I> transcription during fasting and Wy14643 treatment.</P></▼1><▼2><P>Insulin-like growth factor (IGF)-binding protein-2 (IGFBP-2) is known to attenuate the biological action of IGF-1, but its regulatory mechanism remains unclear. We demonstrate the transcriptional regulation of the hepatic <I>Igfbp-2</I> gene by peroxisome-proliferator-activated receptor (PPAR) α during fasting. We also show how PPARα controls IGF-1 signalling through IGFBP-2.</P></▼2>

실험적 간발암 및 폐전이에 관한 병리학적 연구

안병우,김대중,한범석,김기석,강진석,장자준,장동덕 식품의약품안전청 1998 식품의약품안전청 연보 Vol.2 No.-

사람 간암발생의 주된 원인은 설치류와는 달리 바이러스성 간염과 곰팡이독소 아플라톡신의 식이상 섭취와 관련이 깊다. 이는 만성땀증으로 인한 세포독성자 염증과정 중에 산생되는 여러 생리활성인자의 BNA 손상이 중요함을 시사하는 것익다. 대부분의 간암실험 모질은 설치류의 간세포가 바이러스에 친화선이 없기 때문에 발암물질을 주로 이용하고 있으며 지속적인 세포손상 효파를 유도하면 발암효과가 개선될 것이라는 것이 우리의 가설이다. '97년도에 삼투압 펌프(osmotic mini pump, Alzet,USA)를 이용한 발암물질의 미량 연속주입(continuous infusion)이 단기간내에 효과적으로 간암을 유발함으로써 그 가설의 타당성을 확인하엿고, 계속하여 보다 낮은 농도와 노출기간의 단축시에도 같은 효과를 보이는가의 여부와 소량의 반복적인 복강투여가 고농도 1혹 튼여와 차이를 보이는지 착인하고자 하였다. 28주 무에 관찰된 종양의 발생률은 DEN 38mg/rat을 투여한 1군에서는 25%(5/20), 19mg/rat을 투여한 2군 에서는 10%(2/20), D로N 5emg/kg을 3회 복강(ip)으로 투여한3군에서는 35%(7/20) 이었다. 본 실험에서 발생한종양의 형태는 간세포종과 간세포암종이었으며 담판상피세포유래 종양은 관찰되지 않았다. 47.5mg의 DEN을 삼투압펌프로 튼여하였을 매 높은 간All포암종의 발생과 폐전이를 보였던 전년도의 결과와 비교해 볼 때 이러한 결과는 세포독성을 유발하는 용량을 적용할 때 종양이 보다 효과적으로 유발됨을 확인할 수 있었다. 간암조직에서 실시한 면역조직화학적 염색에서 iNOS는 선형 간세포암종(glandular hepatocellular carcinoma), 담관종(cholangioma), 증식성 난원세포(proliferative oval cell), 모세혈관내피세포 및 평활근 세포 등에서 특이적으로 발현되었고,peroxynitrite 작용의 지표인자인 3-nitrotyrosiEe은 iNOS가 발현된 세포에 이웃한 조직과 세포에서 발현되었다.이러한 iNO즈와 nitrotyrosine의 발현은 첫째, iNOS는 간암조직에서 특수한 표현형을 가진 세포웨 표자인자 (phenotypic marlter)일 수 있음을 암시하며 , 둘째, iNOS가 특이적으로 란찰된 난원세포, 선형 간세포암종세포. 담 관종세포 등은 공통적인 기원세포를 가지는 것으로 사료되며, 세째, 종양의직에서 iNOS에 의하여 과다하게 생산된 NO는 혈관신생과 세포분화과정에 개입하여 종양의 성장을 촉진하는 것으로 추측된다. Human liver cancers have been associated mainly with chronic inflammations such as viral hepatitis B or C. Th=is suggests that prolonged cell damage by chronic inflammation is critical incancer developmeat. Overfroduction of nitric oxide (NO) and its derivative (NOx, peroxynitrit'e) hasbeen impticated as a cause of tissue damage by inflammation, frhus contributing to turner proluotioB. Ingeneral, chemical carcinogens are used in most of experimental hepatocarcinogenesis since hepatitisvirus does not have hepatotrophic characteristics. Tt was our hypothesis that prolonged liver damage bychemicat carcinogens may be more effective in induction of tLlmors, when compared with single injec-tion. Ovr previous study showed fts potential effects. In the present study we tried to induce liver to-mors and pulmonary Ineta.stases with lower concentration of BEN with the same regiraen. At 23 weekslater the turner incidences from group 1(38mg/rat),2(19mg/rat),3(50mg/kg, ip,3/3weelts) were 25% (5/20), 10% (2/20) and 35% f 7/20), respectively. The comprising tumors were hepatocellular adenomas andhepatocellular carcinomas (HCCs). No biliarf epithelial cell turners and pulmonary metastases were ob-se.ved.'ffe cause of relatively towered incidences comparing with those of our previous studf seemedthat the-deses used in this study(38mg, 19mg) were not enough to give a protonged cell and/or tissuedafnages. We have deruonstrated the expressions of inducible isoform of nitric oxide synthase (iNOS)and 3-nitrotyrosiBe, a marlter of peroxynitrite formation, by immunohistochemistry in liver tumor tis-sues of our previous stud:#. iNOS was located mainly in oval ·eells, capillary endothelial and muscularcells, epithelia of cholangiomas and glandular HCCs. 3-Nitrotyrosine was observed in the cytoplasms ofsome living or apoptotic EICC cells, connective tissues, proteinEceous fluids, sinusoidal endothelia of to-morous hepatocytes and cholangiomas in tumors. From these observations, we suggest that 1) chronictissue damage by chemics.1 carcinogens may act to induce iNOS and peroxynitrite formation, 2) ovalcells play a key role in development and/or growth of turner tissues by secreting NO via iNOS, whichmay also cause tissue damage by peroxynitrite, and 3) iNOS can be considered as a phenotypic markerin cells of ovat cell lineage and neovascularized capillaries in tumor tissues.

Water quality trend after introducing the plan of total maximum daily loads in the nakdong river watershed

Deuk Seok Yang,Jung Min Ahn,Injung Lee,Dong Seok Shin,Kang Young Jung 한국분석과학회 2017 학술대회논문집 Vol.2017 No.11

The phase analysis of spark plasma sintered MgB2 after ball milling.

Kang, Deuk-Kyun,Kim, Dong-Woong,Kim, Cheol-Jin,Ahn, In-Shup American Scientific Publishers 2010 Journal of Nanoscience and Nanotechnology Vol.10 No.1

<P>Mg and amorphous B powders below 10 and 3 micro meter were used as raw materials, and mixed by planetary-mill for 9 hours at argon atmosphere. MgB2 bulk was fabricated at the various temperatures by Spark Plasma Sintering. In the sintering process, mixed powders were sintered in graphite mold, at the pressure of 55 Mpa. The fabricated MgB2 samples were evaluated with XRD, EDS, FE-SEM, PPMS. MgB2, MgO and Fe phases were observed from XRD result. In the results, MgO and Fe were impurity which may affect superconducting properties of MgB2 samples, and it's distribution could be confirmed from EDS mapping result. In order to confirm the formation of MgB2 phase, DTA was used as heating rate of 10 degrees C/min at Ar atmosphere from room temperature to 1200 degrees C. In the PPMS result, the Tc (critical temperature) was about 21 K, and the density of spark plasma sintered samples increased to 1.87 g/cm3 by increasing sintering temperature.</P>

Bender Typed Piezoelectric Multilayer Actuator

Ahn, Byung-Guk,Lee, Dong-Kyun,Han, Deuk-Young,Kang, Chong-Yoon,Park, Ji-Won,Kim, Hyun-Jai,Yoon, Seok-Jin The Korean Ceramic Society 2003 한국세라믹학회지 Vol.40 No.3

A Bender typed Multilayer Actuator(BMA) for decreasing the depolarization effect was designed and fabricated. Unlike bimorph and multimorph actuators in which depolarization occurred, the BMA did not generate depolarization because the polarization and the electric field directions are the same. The simulated results indicate that higher displacement of the BMA can be achieved by increasing input voltage. Compared with the multimorph actuator, the proposed actuator is expected to extend a life time as well as acceptable voltage range.

Highly size-controlled synthesis of metal nanoclusters by inert-gas condensation for nano-devices.

Kang, Il-Suk,Seo, Hyun-Sang,Kim, Deuk-Han,Lee, Taek-Yeong,Yang, Jun-Mo,Hwang, Wook-Jung,Ahn, Chi Won American Scientific Publishers 2010 Journal of Nanoscience and Nanotechnology Vol.10 No.5

<P>Metal nanoclusters were fabricated by inert-gas condensation in a sputtering reactor. From transmission electron microscopy, it was confirmed that copper nanoclusters with a high degree of monodispersity in size of about 5 nm were successfully produced. The conductance of the percolated nanocluster film was measured. In order to incorporate nano-scale arrangement characterizations in nano-devices being operated in air, aging experiments of the specimen after long time in air were carried. Negative temperature coefficient of resistance suggests that surface native copper oxide in core-shell structured nanoclusters was mainly responsible for the conductance, because copper oxide is known as semiconductor. After aged at higher than 100 degrees C, the conductance at room temperature didn't return to the original value. This irreversible phenomenon might be due to coarsening and/or coalescence of copper nanoclusters.</P>

연료전지 자동차용 가솔린 연료 개질기의 개발 : 수학적 Modeling에 의한 alumina의 fine-grinding 특성해석 Fine-grinding characteristics of alumina by Mathematical Modeling

강동민,문동주,류종우,이상득,안병성 한국공업화학회 2002 응용화학 Vol.6 No.2

The fine grinding characteristics of alumina were investigated by an attrition mill. The grinding kinetics approach was successfully applied to the analysis of particle size distributions obtained under various grinding times. The particle size distributions estimated from grinding rate constant were in good agreement with the experimental data. It was found that the grinding rate constant for the alumina decreased with increasing solid contents.

RH-787 투여후 가토 혈당치 변동에 관하여

안득수 ( Deuk Soo Ahn ),강성귀 ( Sung Kyew Kang ),홍기방 ( Ki Bang Hong ),위상양 ( Sang Yang Wi ),박종일 ( Johong II Park ) 대한내과학회 1977 대한내과학회지 Vol.20 No.12