• Journal of the Korean Institute of Telematics and Electronics
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• v.18 no.3
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• pp.42-51
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• 1981

Boron was predeposited into p (100) Si wafer at 94$0^{\circ}C$ for 60minutes to make the back surface field. High tempreature diffusion process at 1145$^{\circ}C$ for 3 hours was immediately followed without removing boron glass to obtain high surface concentration Back boron was annealed at 110$0^{\circ}C$ for 40minutes after boron glass was removed. N+ layer was formed by predepositing with POCI3 source at 90$0^{\circ}C$ for 7~15 minutes and annealed at 80$0^{\circ}C$ for 60min1es under dry Of ambient. The triple metal layers were made by evaporating Ti, Pd, Ag in that order onto front and back of diffused wafer to form the front grid and back electrode respectively. Silver was electroplated on front and back to increase the metal thickness form 1~2$\mu$m to 3~4$\mu$m and the metal electrodes are alloyed in N2 /H2 ambient at 55$0^{\circ}C$ and followed by silicon nitride antireflection film deposition process. Under artificial illumination of 100mW/$\textrm{cm}^2$ fabricated N+PP+ cells showed typically the open circuit voltage of 0.59V and short circuit current of 103 mA with fill factor of 0.80 from the whole cell area of 3.36$\textrm{cm}^2$. These numbers can be used to get the actual total area(active area) conversion efficiency of 14.4%(16.2%) which has been improved from the provious N+P cell with 11% total area efficiency by adding P+ back.

• Journal of Ginseng Research
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• v.28 no.2
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• pp.120-126
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• 2004

Glial cells such as astrocytes and microglial cells are the main source of proinflammatory cytokines and nitric oxide(NO) in the central nervous system, which exert neuroimmune and inflammatory functions and other various neurobiologic effects. Though Panax ginseng C.A. Meyer has been known to strengthen the body's defence mechanisms and also to maintain the homeostasis in the central nervous system, the effects of Panax ginseng on the production of immune and inflammatory mediators have not been studied well in the brain. Therefore, this study was designed to study the effects of ginseng saponins on the production of proinflammatory cytokines and NO in the primary cultures of mixed glial cells. White ginseng saponin, 200-500 $\mu$g/ml, showed significant cytotoxicity after 72 hrs and increased TNF-$\alpha$, IL-$\beta$, and NO production. Lower doses of 50-100 $\mu\textrm{g}$/ml showed little cytotoxicity until 72 hrs and also increased the production of TNF-$\alpha$, IL-1$\beta$, and NO. Triple immune staining showed that white ginseng saponin, 200$\mu\textrm{g}$/ml for 72 ks, induced stellation of astrocytes and iNOS expression exclusively in microglial cells. Taken together, the white ginseng saponin increased the production of proinflammatory cytokines such as TNF-$\alpha$ and IL-1$\beta$, and induced iNOS expression and NO production in mixed glial cell cultures, which may be ascribed to the enhancement of central immune responses and the regulation of inflammatory reactions by Panax ginseng.

• Korean Journal of Optics and Photonics
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• v.18 no.4
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• pp.246-255
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• 2007

The floating image system (FIS) is a device to display input source in the space between fast surface of the display and an observer and it provides pseudo 3D depth to an observer when input source as real object or 2D image was displayed through the optical lens system in the FIS. The Advanced floating image system (AFIS) was designed to give more effective 3D depth than existing FIS by adding front and rear depth cues to the displayed stereogram, which it was used as input source. The magnitude of disparity and size of stereogram were strongly related each other and they have been optimized for presenting 3D depths in a non-optical lens systems. Thus, if they were used in optical lens system, they will have reduced or magnified parameters, leading to problem such as providing incorrect 3D depth cues to an observer. Although the size of stereogram and disparity were demagnified by total magnifying power of optical system, the viewing distance (VD) from the display to an observer and base distance (BD) for the gap between the eyes were fixed. For this reason, the quantity of disparity in displayed stereogram through the existing FIS has not kept the magnifying power to the total optical system. Therefore, we proposed the methods to provide correct 3D depth to an observer by compensating quantity of disparity in stereogram which was satisfied to keep total magnifying power of optical lenses system by AFIS. Consequently, the AFIS provides a good floating depth (pseudo 3D) with correct front and rear 3D depth cues to an observer.

• Proceedings of the Korean Society of Crop Science Conference
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• 2017.06a
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• pp.351-351
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• 2017

Arbuscular mycorrhizal fungi (AMF) are particular soil fungi that benefit many crops and require a symbiosis with plant roots to survive. In our previous study, there was a positive correlation between AMF root colonization and soybean grain yield in a four-year consecutive winter cover crop-soybean rotational system without phosphorus fertilizer. It is suggested that higher AMF root colonization can be a better solution for improving soybean growth and grain yield in P-limited soil. Our purpose in this study was to test the hypothesis that a P application is the main factor improving soybean growth, P nutrition and grain yield, and the benefit from AMF to soybean P uptake and growth in a P-limited soil. Impact of a P application on AMF root colonization and communities in soybean roots and their potential contribution to soybean growth and P nutrition under a five-year P-unfertilized crop rotational system were investigated over two-years. In this study, four cover crop treatments included 1) wheat (Triticum aestivum); 2) red clover (Trifolium pratense); 3) rapeseed (Brassica napus); and 4) fallow in the crop rotation. The amount of triple superphosphate as a P fertilizer applied rate after cultivation of cover crops was 120 and $360k\;ha^{-1}$ in 2014 and 2015, respectively. Soybean roots were sampled at full-flowering and analyzed for AMF communities using polymerase chain reaction-denaturing gradient gel electrophoresis (PCR-DGGE) and quantitative real-time PCR (qPCR) techniques. The AMF root colonization in the soybean roots at full bloom stage was significantly influenced by cover crop and P application throughout the two-year rotation. The two-year rotation of different cover crops or fallow impacted the molecular diversity of AMF communities colonizing roots of soybean. Redundancy analysis (RDA) indicated that AMF communities colonizing roots of soybean were significantly different among cover crop rotations. The AMF communities colonizing roots of soybean were clearly influenced by a P application in the two-year trial. Moreover, a P application may have positively impacts on the AMF communities under P-deficit soil due to the continuous cover crop-soybean rotational system without a P fertilizer.

• Proceedings of the Korean Society of Embryo Transfer Conference
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• 2002.11a
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• pp.97-97
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• 2002

Human eryhropoietin (EPO) is acidic glycoprotein hormone that plays key role in hematopoiesis by facilitating differentiation of erythrocyte and formation of hemoglobin (Hb) and is used for the treatment of anemia. Human EPO is consist of 166 amino acids which is modified by three N-glycosylations (24, 38, 83) and single O-glycosylation (126). N-glycosylation is reported to be related to the cellular secretion and activity of EPO. In this study, we examined effects of mutagenesis in glycosylation site of recombinat hEPO for the cellular secretion during production from cultured CHO cell. We produced rhEpo which was cloned by PCR from human liver cDNA (TaKaRa) in cultured CHO cell. Using supernatant of the culture, ELISA assay and western analysis were performed. To estimate biological activity, 20IU of rhuEpo was subcutaneously injected into four ICR mice. After 8 days, HCT level was increased average 13 per cent, RBC was increased ca. 2${\times}$10$\^$6//${\mu}\ell$. In disease model Rat (anemia c-kit, WSRC-WS/WS), HCT was increased ca. 12%, RBC was increased ca. 1.6${\times}$10$\^$6//${\mu}\ell$. These results suggests that rhEpo we produced has biological activity. To remove glycosylation site by substituting 24, 38, 83, and 126th asparagine (or serine) with glutamic acid, overlapping -extension site-directed mutagenesis was performed. To add novel glycosylation sites, 69, 105th leucine was mutated to asparagine. Mutant EPO construct was transfected into CHO cell. Supernatant of the cell culture was analyzed using ELISA assay with monoclonal anti-EPO antibody (Medac, Germany). Since, several reports for mutagenesis of glycosylation sites showed case-by-case results, we examined both transient expression and stable expression. Addition of novel glycosylation sites resulted no secretion while deletion mutants had little effect except some double deletion mutants (24/83 and 38/83) and triple mutant. We suggest that not single but combination of glycosyl group affect secretion of EPO.

• Research in Plant Disease
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• v.12 no.3
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• pp.260-266
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• 2006

Pythium blight caused by Pythium spp. is one of major diseases in putting green of golf course. In this study, microorganisms which are anatgonistic to Pythium aphanidermatum, a pathogen of pythium blight, were selected primary through in vitro tests, dual culture method and triple layer agar diffusion method. In vivo test against pythium blight were conducted to select the best candidate biocontrol microorganism by pot experiment in a plastic house. Bacillus subtilis GB-0365 was finally selected as a biocontrol agent against pythium blight. Relative Performance Indies(RPI) was used as a criterion of selecting potential biocontrol agent. B. subtilis GB-0365 showed resistance to major synthetic agrochemicals used in golf course. Alternative application of synthetic agrochemicals and B. subtilis GB-0365 was most effective to successfully contol pythium blight. B. subtilis GB-0365 suppressed the development of pythium bight of bentgrass by 56.4% as compared to non-treated control and its disease control efficacy was 60.9% of a synthetic fungicide Oxapro(WP) efficacy. B. subtilis GB-0365 has a potential to be a biocontrol agent for control of pythium blight.

• Pediatric Gastroenterology, Hepatology & Nutrition
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• v.14 no.1
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• pp.45-51
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• 2011

Purpose: The antimicrobial resistance of Helicobacter pylori is one of the critical factors in failure of eradication therapy. The purpose of this study was to evaluate antimicrobial resistance of H. pylori in Korean children. Methods: Gastric mucosal specimens for H. pylori were obtained from children with dyspepsia who were cared for at Asan Medical Center Children's Hospital in Seoul, Korea between 2003 and 2009. Antimicrobial resistance tests were performed using the disk diffusion method for clarithromycin and amoxicillin and the E-test for metronidazole and tetracycline. Most children with H. pylori infections were treated using triple therapies. Results: Thirty-three children had positive H. pylori cultures, although a resistance test was only performed in 28 patients. Resistant strains were found in 9 children (32.1%). The resistance rates to clarithromycin and metronidazole were 25% and 17.8%, respectively. There was no resistance to amoxicillin or tetracycline. The resistance rates decreased from 44.4% (2003~2006) to 26.3% (2006~2009) during the study period. Conclusion: Korean children demonstrated relatively high antimicrobial resistance to H. pylori in this study. However, there was a temporarily decreasing trend during the study period. A larger multi-regional study may be needed to determine the optimal antimicrobial treatment for pediatric patients infected with H. pylori.

• Journal of Veterinary Clinics
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• v.7 no.2
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• pp.511-515
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• 1990

Induction of twinning was attempted by transfer of two whole- or demi-embryos in Holstein cows and heifers. Cows were superovulated with follicle stimulating hormone(FSH) administered twice daily in intra-muscular injection. On day of 6.5 to 7 post-estrus, embryos were collected nonsurgically, Normal morulae and early balstocysts were obtained from superovulated cows. The embryos were hisected with a micro-blade made from a razor. Twenty seven pairs of half embryos were successfully produced and 23 pairs of half embryos were transferred to recipients( Group A). Twenty cows were treated with low unit of FSH (3mg${\times}$2,2mg${\times}$2 ; Group B1, 2mg${\times}$2, 1mg${\times}$2, 1mg${\times}$2 ; Group 32) to induce double or triple ovulations. The cows of Group B1 and B2 were Inseminated artificially(A1) at following estrus. Twenty four heifers were bred by A1 and received an additional embryo into the uterine horn contralateral to the corpus luteum(CL) 6 days later(Group C). One embryo was transferred into each uterine hem of 16 heifers 6 days after estrus(Group D). Fourteen heifers were received two embryos into the uterine horn ipsilateral to the CL at day 6 of estrous cycle(Group I). Pregnancy rates at 60 days in Group A, B1, B2, C, D and E were 34.8％, 70.0％, 60.0％, 66.7％, 62.5％ and 57.1％, respectively. Twinning rates were 8.7％, 20.0%, 10.0％, 16.7％, 18.7％ and 21.4％, respectively. The present experiments demonstrate that FSH treatment( Group 31) and ipsilateral transfer( Group I ) of two whole-embryos are more useful methods to produce twins than the others.

• Journal of the Korean Wood Science and Technology
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• v.46 no.5
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• pp.610-621
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• 2018

In conservation treatment lacquer has been used variously as a restoration material. However, dealing with Lacquer is very difficult as it dried in high humidity that can be harmful to the base materials. Also being natural varnish, dried lacquer layer is very different from the drying condition and the quality of the lacquer. These make difficult to predict the result of drying lacquer. In this study, using the humidity control machine, firstly, the main contents of the two different type of lacquer was experimented. And these lacquers was cured in various conditions. The duration time was checked until totally hardened. After that, obtained lacquer layers was analyzed to understand optical properties. Therefore, this study made a result about the relationship between characteristics of lacquer layer and the hardening condition. As a result, duration time of the Korean lacquer drying which has average 13.4% more urushiol than the Chinese lacquer is recorded a twice or triple decrease over it of the Chinese one. And, in all types of lacquer, the higher humidity makes the faster a pace of lacquer dried. In same lacquer, the shorter the duration time of drying lacquer is much darker and glossier. However, gloss deteriorated in saturated humidity. In humidity lower than RH 70%, lacquer is not hardened in 336 hours. When the layer totally cured through long period more than 30 days, the drying lacquer is appeared high brightness and almost transparent. Thus, in lower than RH 70%, it is hard to obtain durable layer.

• Korean Journal of Clinical Pharmacy
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• v.16 no.1
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• pp.23-27
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• 2006

Doxorubicin (DXR) is a type of anti-cancer drug called an 'anthracycline glycoside', It works by impairing DNA synthesis, a crucial feature of cell division, and thus is able to target rapidly dividing cells. Doxorubicin is a very serious anti-cancer medication with definite potential to do great harm as well as great good. A liquid chromatography-tandem mass spectroscopy (LC-MS/MS) method was developed to identify and quantify DXR in small-volume biological samples. After the addition of internal standard (IS, $5{\mu}L\;of\;1{\mu}M/ml$ daunorubicin methanol solution) into the serum sample, the drug and IS were extracted by methanol. Following vortex for a 1min and centrifugation at 15,000g for 10 min the organic phase was transferred and evaporated under a vacuum. The residue was reconstituted with $350{\mu}L$ of mobile phase and $10{\mu}L$ was injected into C18 column with mobile phase composed of 0.05M ammonium acetate (0.1 M acetic acid adjusted to pH 3.5) and acetonitrile (40:60, v/v). The flow rate was kept constant at $350{\mu}L/min$. The ions were quantified in the multiple reaction mode (MRM), using positive ions, on a triple quadrupole mass spectrometer. The lower limits of quantification for Doxorubicin in plasma and small tissues were approximately 0.5 ng/mL and 0.5 ng/mL respectively. Intra- and inter-assay accuracy (% of nominal concentration) and precision (% CV) for all analytes were within 15%, respectively.