• Molecules and Cells
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• v.25 no.3
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• pp.376-384
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• 2008

The glial fibrillary acidic protein (GFAP) is traditionally used as a marker for astrocytes of the brain, and more recently for the hepatic stellate cells (HSCs) of the liver. Several GFAP splice variants have been previously reported in the astrocytes of the CNS and in the non-myelinating Schwann cells of the PNS. In this study, we investigate whether GFAP splice variants are present in the HSCs and their expression as a function of HSCs activation. Furthermore, the regulation of these transcripts upon treatment with interferon gamma ($IFN-{\gamma}$) will be explored. Using semi-quan-titative RT-PCR and real-time PCR, we examine the expression and regulation of GFAP splice variants in HSCs as well as their respective half-life. We discover that most of the GFAP splice variants ($GFAP{\alpha}$, ${\beta}$, ${\delta}$, ${\varepsilon}$ and $\kappa$) found in the neural system are also expressed in quiescent and culture-activated primary HSCs. Interestingly, $GFAP{\alpha}$ is the predominant form in quiescent and culture-activated primary HSCs, while $GFAP{\beta}$, predominates in the SV40-immortalized activated HSC-T6. $GFAP{\delta}$, ${\varepsilon}$ and ${\kappa}$ have similar half-lives of 10 hours, while $GFAP{\beta}$ has a half-life of 17 hours. Treatment of HSC-T6 with $IFN-{\gamma}$ results in a significant 1.29-fold up-regulation of $GFAP{\alpha}$ whereas the level of the other transcripts remains unchanged. In summary, $GFAP{\alpha}$, ${\beta}$, ${\delta}$, ${\varepsilon}$ and $\kappa$ are present in HSCs. They are differentially regulated on the transcription level, implying a role of the 5' and 3' untranslated regions.

• Korean Journal of Food Science and Technology
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• v.29 no.3
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• pp.522-526
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• 1997

Soy isoflavones could be recovered with adsorption resin column chromatography from soybean cooking water produced during soymilk or tofu manufacturing process. The main isoflavones in the soybean cooking water were genistin and daidzin, and their concentration was $0.083{\pm}0.019$ and $0.11{\pm}0.017\;mM$, respectively. Their aglycones were not detected. pH of soybean cooking water was critical in this chromatographic process and the recovery of isoflavones, both genistin and daidzin, was maximum at pH 4.0. Adsorption of genistin on the resin was stronger than that of daidzin. Elution rate and height/diameter ratio also affected the recovery yield. Under the optimal conditions, about 85% of genistin and 70% of daidzin could be isolated from soybean cooking water. Soy saponins were also recovered with isoflavones.

• Journal of the Korea Convergence Society
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• v.8 no.3
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• pp.191-197
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• 2017

This development is for non-destructive machine using X-Ray source about detecting outline faults of below middle size products. The differentiation is product of research and development unspecialized small and medium-sized products using X-Ray light sources can check real time if the surface of an external fault of radiation dose reference, within the leakage. The speed control is possible by software solution. In addition, we're working on possibly block doors for worker safety and equipment at the same time that inner drive can be identified in the image. These principles, as a key enabler of the current inspection system such as the container is small to medium-sized parts - a long way from utilization level is possible. This research will give rise to major effects for other various non-destructive market industries except car-industry. The most important fact is that this developed non-destructive machine is controlled below $0.2micro-S{\mu}v$.

• Imaging Science in Dentistry
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• v.48 no.1
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• pp.21-30
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• 2018

Purpose: To calculate the effective doses of cone-beam computed tomography (CBCT) using personal computer-based Monte Carlo (PCXMC) software (Radiation and Nuclear Safety Authority, Helsinki, Finland) and to compare the calculated effective doses with those measured using thermoluminescent dosimeters (TLDs) and an anthropomorphic phantom. Materials and Methods: An Alphard VEGA CBCT scanner (Asahi Roentgen Ind. Co., Kyoto, Japan) with multiple fields of view (FOVs) was used for this study. The effective doses of the scout and main projections of CBCT using 1 large and 2 medium FOVs with a height >10 cm were calculated using PCXMC and PCXMCRotation software and then were compared with the doses obtained using TLD-100 LiF and an anthropomorphic adult human male phantom. Furthermore, it was described how to determine the reference points on the Y- and Z-axes in PCXMC, the important dose-determining factors in this software. Results: The effective doses at CBCT for 1 large ($20.0cm{\times}17.9cm$) and 2 medium FOVs ($15.4cm{\times}15.4cm$ and $10.2cm{\times}10.2cm$) calculated by the PCXMC software were 181, 300, and $158{\mu}Sv$, respectively. These values were comparable (16%-18% smaller) to those obtained through TLD measurements in each mode. Conclusion: The use of PCXMC software could be an alternative to the TLD measurement method for effective dose estimation in CBCT with large and medium FOVs.

• Publications of The Korean Astronomical Society
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• v.27 no.3
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• pp.81-86
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• 2012

The International Space Station (ISS) orbits the Earth within the inner radiation belt, where high-energy protons are produced by collisions of cosmic rays to the upper atmosphere. About 6 astronauts stay in the ISS for a long period, and it should be important to monitor and assess the radiation environment in the ISS. The tissue equivalent proportional counter (TEPC) is an instrument to measure the impact of radiation on the human tissue. KASI is developing a TEPC as a candidate payload of the ISS. Before the detailed design of the TEPC, we performed simulations to test whether our conceptual design of the TEPC will work propertly in the ISS and to predict its performance. The simulations estimated that the TEPC will measure the dose equivalent of about 1:1 mSv during a day in the ISS, which is consistent with previous measurements.

• The Bulletin of The Korean Astronomical Society
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• v.36 no.1
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• pp.27.2-27.2
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• 2011

The Kepler(NASA) and CoRoT(ESA) space telescopes are surveying thousands of exoplanet for finding Earth-like exoplanets with similar environments of the Earth. Then the TPF(NASA), DARWIN(ESA) and many large-aperture ground telescopes have plan for spectroscopic observations of these earth-like exoplanets in next decades. Now, it has been started to simulate the disk averaged spectra of the earthlike exoplanets for comparing the observed spectra and suggesting solutions of environment of these planets. Previous research, the simulations are based on radiative transfer method, but these are limited by optical models of Earth system and instruments. We introduce a new simulation method, IRT(Integrated Ray Tracing) to overcome limitations of previous method. The 3 components are defined in IRT; 1)Sun model, 2)Earth system model (Atmosphere, Land and Ocean), 3)Instrument model. The ray tracing in IRT is simulated in composed 3D real scale space from inside the sun model to the detector of instrument. The Sun model has hemisphere structure with Lambertian scattering optical model. Atmosphere is composed of 16 distributed structures and each optical model includes BSDF with using 6SV radiative transfer code. Coastline and 5 kinds of vegetation distribution data are used to land model structure, and its non-Lambertian scattering optical model is defined with the semi-empirical "parametric kernel method" used for MODIS(NASA) and POLDER(CNES) missions. The ocean model includes sea ice cap structure with the monthly sea ice area variation, and sea water optical model which is considering non-lambertian sun-glint scattering. Computation of spectral imaging and radiative transfer performance of Earth system model is tested with hypothetical space instrument in IRT model. Then we calculated the disk averaged spectra of the Earth system model in IRT computation model for 8 cases; 4 viewing orientation cases with full illuminated phase, and 4 illuminated phase cases in a viewing orientation. Finally the DAS results are compared with previous researching results of radiative transfer method.

• Journal of the Korea Concrete Institute
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• v.14 no.1
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• pp.1-7
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• 2002

The purpose of this research is to obtain a practical expression for the estimation of compressive strength of concrete using non-destructive testing method such as rebound Schmidt hammer and ultrasonic pulse

• Proceedings of the Korean Information Science Society Conference
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• 2003.10a
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• pp.190-192
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• 2003

소비자의 신용 대출 규모가 점차 증가하면서 기업에서 고객의 신용 등급에 의한 정확한 고객 분류를 필요로 하고 있다 이를 위해 판별 분석과 신경망의 역전파(BP: Back Propagation)를 이용한 고객 분류 시스템이 연구되었다. 그러나, 판별 분석을 사용한 방법은 불규칙한 신용 거래의 성향을 보이는 비정규 분포의 고객 데이터의 영향으로 여러 개의 판별 함수와 판별점이 존재하여 분류 정확도가 떨어지는 단점이 있다. 신경망을 이용한 방법은 불규칙한 신용 거래의 성향을 보이는 고객 데이터에 의해서, 지역 최소점(Local Minima)에 빠져 최대의 분류 정확률을 보이는 분류자를 얻지 못하는 경우가 발생할 수 있다. 본 논문에서는 이러한 기존 연구의 분류 정확률을 저하시키는 단점을 해결하기 위해 SVM(Support Vector Machine)을 사용하여 고객의 신용 등급을 분류하는 방법을 제안한다. SVM은 SV(Support Vector)의 수에 의해서 학습 성능이 좌우되므로, 불규칙한 거래 성향을 보이는 고객에 대해서도 높은 차원으로의 매핑을 통하여, 효과적으로 학습시킬 수 있어 분류의 정확도를 높일 수 있다 하지만, SVM은 근사화 알고리즘(Approximation Algorithms)을 이용하므로 분류 정확도가 이론적인 성능에 미치지 못한다. 따라서, 본 논문은 점진적 앙상블 SVM을 사용하여, 기존의 고객 분류 시스템의 문제점을 해결하고 실제적으로 SVM의 분류 정확률을 높인다. 실험 결과는 점진적 앙상블 SVM을 이용한 방법의 정확성이 기존의 방법보다 높다는 것을 보여준다.

• Proceedings of the Korean Powder Metallurgy Institute Conference
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• 1997.04a
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• pp.34-34
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• 1997

The effect of alloying mode and porosity on the axial tension-tension fatigue behavior of a P/M steel of nominal composition Fe-4w/o Ni-1.5w/o Cu-O.5w/o Mo-O.5w/o C has been evaluated. Alloying modes utilized were elemental powder mixing, partial alloying(distaloy) and prealloying by water atomization; in each case the carbon was introduced as graphite prior to sintering. Powder compacts were sintered($1120{\circ}C$/30 min.) in 7Sv/o $H_2$/25v/o $N_2$ to densities in the range 6.77-7.2 g/$cm^3$. The dependence of fatigue limit response on alloying mode and porosity was interpreted in terms of the constituent phases and the pore and fracture morphologies associated with the three alloying modes. For the same nominal composition, the three alloying modes resulted in different sintered microstructures. In the elemental mix alloy and the distaloy, the major constituent was coarse and fine pearlite, with regions of Ni-rich ferrite, Ni-rich martensite and Ni-rich areas. In contrast, the prealloy consisted primarily of martensite by with some Ni-rich areas. From an examination of the fracture surfaces following fatigue testing it was concluded that essentially all of the fracture surfaces exhibited dimpled rupture, characteristic of tensile overload. Thus, the extent of growth of any fatigue cracks prior to overload was small. The stress amplitude for the three alloying modes at 2x$l0^6$ was used for the comparison of fatigue strengths. For load cycles <3x$l0^5$, the prealloy exhibited optimum fatigue response followed by the distaloy and elemental mix alloy, respectively. At load cycles >2x$l0^6$, similar fatigue limits were exhibited by the three alloys. It was concluded that fatigue cracks propagate primarily through pores, rather than through the constituent phases of the microstructure. A decrease in pore SIze improved the S-N behavior of the sintered steel.

• International Journal of Safety
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• v.10 no.2
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• pp.6-9
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• 2011

Examples and experiences of risk management on radiation under prolonged exposure situation are shown. The accident of the Fukushima dai-ichi nuclear power plant after the great east Japan earthquake (11 March, 2011) elevates background level of environmental radiation around the east Japan. For example, ambient dose equivalent rate around Tohkatsu area next to Tokyo located about 200 km-south from the plant, is about 0.1-0.6 micro-Sv $h^{-1}$ mainly due to $^{134}Cs$ and $^{137}Cs$ falling on the ground soil. This level is about double or up to ten times higher than the genuine natural level around the area. International Commission on Radiological Protection (ICRP) recommends how to face the existing exposure situation; that is the prolonged exposure situation. Referring to ICRP's reports and/or related international/domestic documents, we have been discussing how to manage this situation and acting to gain safety and relief of public, who have a possibility to be exposed to prolonged lower-dose radiation. Here, we introduce our several experiences on risk management, especially focusing on risk communication, radiation education to public, and stakeholder involvements into decision making in local governments on radiation protection, relating to the accident.