• 한국초전도학회:학술대회논문집
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• 한국초전도학회 1999년도 High Temperature Superconductivity Vol.IX
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• pp.280-290
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• 1999

The microstructures of a Tl$_{0.8}Pb_{0.2}Bi_{0.2}Sr_{1.6}Ca_2Cu_3O_{9+{\delta}}$/Ag tape (tape I ) with J$_c$ of 17,600 A/cm$^2$ at 77 K and 0 T and three Tl$_{0.8}Pb_{0.2}Bi_{0.2}Sr_{1.8}Ba_{0.2}Ca_{2.2}Cu_3O_{9+{\delta}}$/Ag tapes with J$_c$'s of 9,300 (tape II), 16,700 (tape III) and 25,200 A/cm$^2$ (tape IV)prepared using the powder-in-tube method and an in-situ reaction method, were investigated using scanning electron microscopy and high-resolution transmission electron microscopy, and compared each other. ln the tape preparation, an intermediate rolling process was incorporated during final heat-treatment for the last tape, but not for the rest of the tapes. The microstructural analysis revealed clear differences in grain-texturing, crystallographic defects and impurity phases, depending on the chemical composition of the tape. Tendency of directional grain-alignment increased in an order of tapes I, II III and IV. In tape IV, T1-1223 grains are textured, at least in local regions. In crystallographic defects, while stacking faults were prevalent in the former composition, dislocations and voids were frequently observed in the latter. Also impurity phases were appeared to be more abundant in the former than in the latter. The relationship between 1,and the microstructure in the tapes was attempted to explain in a term of grain-linking.

• Journal of Acupuncture Research
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• 제29권1호
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• pp.25-35
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• 2012

목적 : 이 연구는 $Vipera$ $lebetina$ $turanica$ 사독(蛇毒)이 인간 대장암 세포주인 HCT116 세포에서 세포주기진행, death receptor 의존적 세포자멸사 경로 관련단백질 발현 및 NK-${\kappa}B$와 STAT3 활성에 미치는 영향을 규명함으로써 대장암 세포 성장에 대한 억제와 그 기전에 대하여 살펴보고자 하였다. 방법 : 사독을 처리한 후 HCT116의 세포주기를 분석하기 위해서 FACS analysis를 시행하였고, apoptosis 평가에는 TUNEL assay를 시행하였으며 death receptor 의존적 세포자멸사 경로 관련단백질 및 NF-${\kappa}B$와 STAT3 활성 변동 관찰에는 RT-PCR 및 western blot analysis를 시행하였다. 결과 : 1. 0.1, 0.5 및 $1{\mu}g/m{\ell}$ 등의 사독을 처리한 결과 농도 의존적으로 HCT116 대장암 세포활성의 억제가 나타났다. 2. 0.1, 0.5 및 $1{\mu}g/m{\ell}$ 등의 사독을 처리한 결과 농도의존적으로 세포자멸사 활성세포의 증가가 나타났고, SVT $1{\mu}g/m{\ell}$에서는 60-70%의 대장암세포 억제 효과가 나타났다. 3. 0.1, 0.5 및 $1{\mu}g/m{\ell}$ 등의 사독을 처리한 결과 약한 G1 arrest와 강한 G2/M arrest가 나타났고, G0/G1 또는 G2/M 관련 cyclin D, E 및 B1의 증가가 나타났다. 4. 0.1, 0.5 및 $1{\mu}g/m{\ell}$ 등의 사독을 처리한 결과 death receptor4, 5의 발현증가와 그에 따른 세포자멸사 촉진 Bax, PARP, caspase-3, -8, -9 발현 증가 및 세포자멸사 억제의 Bcl-2의 발현 감소 등이 나타났다. 6. 0.1, 0.5 및 $1{\mu}g/m{\ell}$ 등의 사독을 처리한 결과 NF-${\kappa}B$와 STAT3의 활성변동은 관찰되지 않았다. 결론 : 이상의 연구에서 사독은 death receptor 의존적인 세포자멸사를 촉진하여 대장암의 화학치료 내성을 극복할 수 있는 하나의 대안이 될 것으로 생각되지만 보다 심화된 연구가 필요할 것으로 사료된다.

• The Journal of the Acoustical Society of Korea
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• 제25권3E호
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• pp.115-122
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• 2006

The bistatic scattering of an incident wave by a hemi-spherically capped cylinder is of particular interest because it has rarely been studied until the present day. The configuration of a hemi-spherically capped cylinder is similar to naval underwater weapons (submarines, mines, torpedos, etc.), but which is not exactly the same. This paper describes a novel laboratory experiment aimed at direct measurement of bistatic scattering by a hemi-spherically capped cylinder. Bistatic scattering by a hemi-spherically capped cylinder was measured in an acoustic water tank (5m long, 5m wide, 5m deep) using a high frequency projector (120kHz) and hydrophone. Measurements of monostatic scattering were also made under the same conditions. The bistatic scattering pattern by a hemi-spherically capped cylinder was measured against the incident angles $(0^{\circ},\;15^{\circ},\;20^{\circ},\;30^{\circ},\;45^{\circ},\;60^{\circ},\;90^{\circ})$ in order to verify various scattering pattern characteristics by the change of incident angle. The results indicate that the bistatic scattering TS at a wide scattering angle is much stronger than the mono static scattering TS. In bistatic scattering, the forward scattering TS is significantly stronger than the backward scattering TS, and the forward scattering pattern is also broader. In case of seven incident angles, the maximum value of forward scattering TS is about 14dB stronger than that of backward scattering TS. It is also found that forward scattering varies with the incident angle of sound to a much less extent than backscattering, and it is not seriously affected by the incident angle. These features could be the advantages of using forward scattering for detecting underwater targets at long range and increasing detection area and probability.

• 한국수소및신에너지학회논문집
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• 제29권1호
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• pp.41-55
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• 2018

General polymer electrolyte fuel cell (PEMFC) operates at less than $80^{\circ}C$. Therefore liquid phase water resulting from electrochemical reaction accumulates and floods the cell which in turn increases the mass transfer loss. To prevent the flooding, it is common to employ serpentine flow channel, which can efficiently export liquid phase water to the outlet. The major drawback of utilizing serpentine flow channel is the large pressure drop that happens between the inlet and outlet. On the other hand, in the high temperature polymer electrolyte fuel cell (HT-PEMFC), since the operating temperature is 130 to $180^{\circ}C$, the generated water is in the state of gas, so the flooding phenomenon is not taken into consideration. In HT-PEMFCs parallel flow channel with lower pressure drop between the inlet and outlet is employed therefore, in order to circulate hydrogen and air in the cell less pumping power is required. In this study we analyzed HT-PEMFC's different flow channels by parallel computation using previously developed 3-D isothermal model. All the flow channels had an active area of $25cm^2$. Also, we numerically compared the performance of HT-PEMFC parallel flow channel with different manifold area and Rib interval against the original serpentine flow channel. Results of the analysis are shown in the form of three-dimensional contour polarization curves, flow characteristics in the channel, current density distribution in the Membrane, overpotential distribution in the catalyst layer, and hydrogen and oxygen concentration distribution. As a result, the performance of a real area fuel cell was predicted.

• Natural Product Sciences
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• 제20권4호
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• pp.274-280
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• 2014

Six compounds were isolated from the n-BuOH fraction of the aerial parts of Aruncus dioicus var. kamtschaticus including: sambunigrin (1), prunasin (2), aruncide A (3), aruncide C (4), 1-O-caffeoyl-${\beta}$-D-glucopyranose (5), and caffeic acid (6). Their structures were confirmed by comparing the spectral data with those reported in the literature. The isolated compounds (1 - 6) were then examined for their cytotoxic effects towards MCF-7, HL-60, and HeLa cancer cell lines, as well as their DPPH radical scavenging activity. The results indicated that compound 4 possessed the strongest inhibitory effect toward HeLa cell line with $IC_{50}$ value of $5.38{\pm}0.92{\mu}M$. Compound 3 possessed selective cytotoxic activity on HL-60 cells with $IC_{50}$ value of $6.27{\pm}0.17{\mu}M$, compound 5 was found as the best in inhibiting proliferation with $IC_{50}$ value of $2.25{\pm}0.09{\mu}M$, and the other compounds showed significant inhibition with $IC_{50}$ values ranging from 6.10 to $11.27{\mu}M$. Compound 5 also displayed the strongest cytotoxic effect toward MCF-7 cell line ($IC_{50}$ $4.32{\pm}0.15{\mu}M$). Both 5 and 6 demonstrated strong radical scavenging activity ($IC_{50}$ $6.87{\pm}0.03$ and $4.33{\pm}0.22{\mu}M$, respectively). Compounds 1 and 5 were isolated for the first time from this plant.

• Asian-Australasian Journal of Animal Sciences
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• 제21권3호
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• pp.340-345
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• 2008

Oxidative stress is one of the major causes of failure of in vitro storage of boar semen. Reactive oxygen species (ROS) are one of the important mediators of oxidative stress during in vitro storage of boar semen. Our study examined the effects of taurine on sperm characteristic and on in vitro developmental embryos during in vitro storage of boar semen for 7 days. Semen was randomly aliquoted into 3 centrifuge tubes and treated with different concentrations of taurine (25-100 mM). The characteristics of boar sperm were analyzed for motility by light microscopy, viability by using a Makler counting chamber and membrane integrity by a hypoosmotic swelling test (HOST). The percentages of motile spermatozoa in taurine groups after 5 days were significantly higher compared to the control. Sperm viability in the control was lower than in taurine groups after 7 days irrespective of different taurine concentration. In the hyoosmotic swelling test (HOST), significantly higher results were obtained in taurine groups after 3 days. Also, the developmental rates of IVM/IVF porcine embryos from semen treated with pyruvate and taurine were significantly increased when compared with the control (p<0.05). These results indicate that supplementation of taurine as an antioxidant in boar semen extender can improve the semen quality.

• 비파괴검사학회지
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• 제33권2호
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• pp.212-218
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• 2013

A transfer method of neutron radiography was developed to measure the size of the end plug and a gap of an intact K102L-2, the irradiated fuel of a ballooned K174L-3, a ballooned and ruptured K98L-3. A typical irradiation time of 25 min. was determined to obtain a film density of between 2 and 3 of SR X-ray film with neutrons of $1.5{\times}10^{11}n{\cdot}cm^{-2}$. To validate and calibrate the results, a RISO fuel standard sample, Cd plate and ASTM-BPI/SI were used. An activated latent image formed in the $100{\mu}m$ Dy foil was subsequently transferred in a dark room for more than 8 hours to the SR film which is a maximum of three half-lives. Due to the L/D ratio an unsharpness of $9.82-14{\mu}m$ and a magnification of 1.0003 were given. After digitizing an image of SR film, the ballooning gap of the plug was discernible by an H/V filter of image processing. The gap size of the ballooned element, K174L-3, is equal to or greater than 1.2 mm. The development of a transfer method played a pivotal role in developing high burn-up of Wolsung and PWR nuclear fuel type.

• 한국식품영양학회지
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• 제30권1호
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• pp.83-95
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• 2017

This study examined the socioeconomic factors that affect self-rated health (SRH) in healthy adults, and the relationship of SRH to health-related habits, serum biochemical indices, and nutritional intakes. Subjects consisted of 1,154 healthy adults without any known disease, aged 19 to 65 years (average age of 36.7), whose information was obtained from the 2013 Korean National Health and Nutritional Examination Survey data. Of these subjects, 73 rated themselves as 'very healthy,' 460 indicated that they were 'healthy,' 568 self-identified as 'ordinary', and 53 put themselves in the 'unhealthy' category. The proportion of subjects who chose 'unhealthy' was significantly increased with higher frequencies of disruptions in their daily lives (p<0.05), regret after drinking (p<0.05), smoking (p<0.001), and higher levels of stress (p<0.001). On the other hand, the proportion of subjects reported as 'very healthy' was significantly higher with regular intense (p<0.001) or moderate physical activities (p<0.05), regular walking (p<0.05), a perception of being 'normal' in their body image (p<0.01), a decrease of body weight more than 3 kg in the past year (p<0.05), and without risk factors for metabolic syndrome (p<0.05). Serum triglyceride level was lower, and 25-(OH) vitamin D content was significantly higher, in the 'very healthy' group as compared to the 'unhealthy' group (p<0.05). Dietary fiber and vitamin C intakes were significantly higher in the 'very healthy' group than 'unhealthy' group (p<0.05). The overall results suggest that a healthy lifestyle, including regular exercise, non-smoking, good stress management, and higher intakes of fiber and vitamin C, may be potential factors that affect one's positive perception of health.

• Asian-Australasian Journal of Animal Sciences
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• 제19권1호
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• pp.7-12
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• 2006

The objective of this study was to estimate genetic parameters between first and later parities as different traits in reproductive traits of pigs using multiple trait animal model procedures. Data related to reproductive traits from a total of 2,371 individuals maintained at a farm were taken from the pedigree file. Sires and dams were consisted of Duroc, Landrace, and Yorkshire breeds, respectively. The first and later parity records were considered as different traits. Traits included in analyses were total pigs born (TB1), number of pigs born alive (NBA1), number of pigs weaned (NW1), and litter weaning weight (LWT1) in the first parity, and total pigs born (TB2), number of pigs born alive (NBA2), number of pigs weaned (NW2), litter weaning weight (LWT2) and interval between farrowing events (FTF) in later parities. Heritability estimates of TB1, NBA1, NW1 and LWT1 in the first parity were 0.27, 0.25, 0.16 and 0.20, respectively. For TB2, NBA2, NW2, LWT2 and FTF in later parities, heritabilities were estimated as 0.15, 0.15, 0.08, 0.11 and 0.07, respectively. Genetic correlations between sow reproductive traits in the first parity and in the second and later parity were estimated to be 0.89, 0.77, 0.58 and 0.66, respectively, between TB1 and TB2, NBA1 and NBA2, NW1 and NW2, and LWT1 and LWT2. While phenotypic correlations between TB1 and TB2, NBA1 and NBA2, NW1 and NW2, and LWT1 and LWT2 were estimated as 0.18, 0.15, 0.06 and 0.10, respectively. Genetic correlations between reproductive traits of first and later parities were not high indicating that reproductive traits for sows should be analyzed while considering the parities as different traits.

• 한국약용작물학회지
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• 제14권4호
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• pp.239-243
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• 2006

개화 이후 고사하는 일임성 식물인 바위솔은 가을철에 집중되는 자연산의 출하시기와 중복되지 않도록 비가림 하우스에서 인공재배되고 있다. 본 연구는 하우스 시설로 인한 차광 (무차광, 35, 55, 75, 95% 차광)이 바위솔의 생장 및 개화에 미치는 영향을 파악하고자 실시되었던 바 그 결과를 요약하면 다음과 같다. 1. 초장, 화서장, 엽과 포엽수 및 경직경은 광도가 가장 약한 95% 차광시 가장 짧고, 적거나, 가늘었던 반면, 여타 차광 처리간에는 차이가 적다 할지라도 차광이 심할수록 줄어드는 경향을 보였다. 2. 엽과 포엽중, 경중, 근중, 지상부중, 전체건물중은 무차광에서 가장 많았으며 차광이 심할수록 감소되는 경향을 보였다. 3. 형성된 소화수는 건물중과 같이 무차광에서 가장 많고 차광이 심할수록 감소되었으나, 95% 차광시 아주 적었다. 4. 차광처리로 소화가 개화된 개체는 관찰되지 않아 광도가 제한되는 시설하우스에서 여타 처리를 통하여 바위솔의 인공재배는 가능할 것으로 판단된다.