• 대한한방부인과학회지
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• 제22권3호
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• pp.66-82
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• 2009

Purpose: This study was performed to elucidate the inhibitory effect of Yukmijihwangtang-gagambang (YMG) on melanin synthesis in B16F10 mouse melanoma cell. Methods: To demonstrate the inhibitory effects of YMG on melanin synthesis, we measured the amount of released and produced melanin in B16F10 melanoma cell. Also, we evaluated tyrosinase-activity in vitro as well as in B16F10 melanoma cell. And to investigate the action mechanism we assessed the gene expressions of tyrosinase, TRP-1, TRP-2, MMP-2, PKA, PKC${\beta}$, ERK-1 ERK-2, AKT-1 and MITF in B16F10 melanoma cells. Results: 1. YMG decreased the release and production of melanin in B16F10 melanoma cells. 2. YMG decreased tyrosinase activity in vitro and in B16F10 melanoma cells. 3. YMG decreased the expression of tyrosinase, TRP-1, TRP-2, PKA, PKC${\beta}$ and MMP-2 in B16F10 melanoma cells. 4. YMG increased the expression of ERK-1, ERK-2, and AKT-1 in B16F10 melanoma cells. 5. YMG decreased the expression of MITF in B16F10 melanoma cells. Conclusion: From these results, we suggest that YMG inhibit melanin synthesis via tyrosinase inhibition and regulation of the gene expression in B16F10 melanoma cells.

• Journal of applied mathematics & informatics
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• 제32권5_6호
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• pp.849-856
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• 2014

In this paper we introduce the notion of medial B-algebras, and we obtain a fundamental theorem of B-homomorphism for B-algebras.

• Journal of Electrical Engineering and Technology
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• 제5권2호
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• pp.342-351
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• 2010

The SiC-$ZrB_2$ composites were fabricated by combining 30, 35, 40, 45 and 50 vol. % of zirconium diboride ($ZrB_2$) powders with silicon carbide (SiC) matrix. The SiC-$ZrB_2$ composites and the sintered compacts were produced through spark plasma sintering (SPS) under argon atmosphere, and its physical, electrical, and mechanical properties were examined. Also, the thermal image analysis of the SiC-$ZrB_2$ composites was examined. Reactions between $\beta$-SiC and $ZrB_2$ were not observed via x-ray diffraction (XRD) analysis. The apparent porosity of the SiC+30vol.%$ZrB_2$, SiC+35vol.%$ZrB_2$, SiC+40vol.%$ZrB_2$, SiC+45vol.%$ZrB_2$ and SiC+50vol.%$ZrB_2$ composites were 7.2546, 0.8920, 0.6038, 1.0981, and 10.0108%, respectively. The XRD phase analysis of the sintered compacts demonstrated a high phase of SiC and $ZrB_2$. Among the $SiC+ZrB_2$ composites, the SiC+50vol.%$ZrB_2$ composite had the lowest flexural strength, 290.54MPa, the other composites had more than 980MPa flexural strength except the SiC+30vol.%$ZrB_2$ composite; the SiC+40vol.%$ZrB_2$ composite had the highest flexural strength, 1011.34MPa, at room temperature. The electrical properties of the SiC-$ZrB_2$ composites had positive temperature coefficient resistance (PTCR). The V-I characteristics of the SiC-$ZrB_2$ composites had a linear shape in the temperature range from room to $500^{\circ}C$. The electrical resistivities of the SiC+30vol.%$ZrB_2$, SiC+35vol.%$ZrB_2$, SiC+40vol.%$ZrB_2$ SiC+45vol.%$ZrB_2$ and SiC+50vol.%$ZrB_2$ composites were $4.573\times10^{-3}$, $1.554\times10^{-3}$, $9.365\times10^{-4}$, $6.999\times10^{-4}$, and $6.069\times10^{-4}\Omega{\cdot}cm$, respectively, at room temperature, and their resistance temperature coefficients were $1.896\times10^{-3}$, $3.064\times10^{-3}$, $3.169\times10^{-3}$, $3.097\times10^{-3}$, and $3.418\times10^{-3}/^{\circ}C$ in the temperature range from room to $500^{\circ}C$, respectively. Therefore, it is considered that among the sintered compacts the SiC+35vol.%$ZrB_2$, SiC+40vol.%$ZrB_2$ and SiC+45vol.%$ZrB_2$ composites containing the most outstanding mechanical properties as well as PTCR and V-I characteristics can be used as an energy friendly ceramic heater or ohmic-contact electrode material through SPS.

• Journal of Electrical Engineering and Technology
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• 제4권4호
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• pp.538-545
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• 2009

The SiC-$ZrB_2$ composites were fabricated by combining 30, 35, 40 and 45vol.% of Zirconium Diboride (hereafter, $ZrB_2$) powders with Silicon Carbide (hereafter, SiC) matrix. The SiC-$ZrB_2$ composites, the sintered compacts, were produced through Spark Plasma Sintering (hereafter, SPS), and its physical, electrical, and mechanical properties were examined. Also, the thermal image analysis of the SiC-$ZrB_2$ composites was examined. Reactions between $\beta$-SiC and $ZrB_2$ were not observed via X-Ray Diffractometer (hereafter, XRD) analysis. The relative density of the SiC+30vol.%$ZrB_2$, SiC+35vol.%$ZrB_2$, SiC+40vol.%$ZrB_2$, and SiC+45vol.%$ZrB_2$ composites were 88.64%, 76.80%, 79.09% and 88.12%, respectively. The XRD phase analysis of the sintered compacts demonstrated high phase of SiC and $ZrB_2$ but low phase of $ZrO_2$. Among the SiC-$ZrB_2$ composites, the SiC+35vol.%$ZrB_2$ composite had the lowest flexural strength, 148.49MPa, and the SiC+40vol.%$ZrB_2$ composite had the highest flexural strength, 204.85MPa, at room temperature. The electrical resistivities of the SiC+30vol.%$ZrB_2$, SiC+35vol.%$ZrB_2$, SiC+40vol.%$ZrB_2$ and SiC+45vol.%$ZrB_2$ composites were $6.74\times10^{-4}$, $4.56\times10^{-3}$, $1.92\times10^{-3}$, and $4.95\times10^{-3}\Omega{\cdot}cm$ at room temperature, respectively. The electrical resistivities of the SiC+30vol.%$ZrB_2$, SiC+35vol.%$ZrB_2$ SiC+40vol.%$ZrB_2$ and SiC+45[vol.%]$ZrB_2$ composites had Positive Temperature Coefficient Resistance (hereafter, PTCR) in the temperature range from $25^{\circ}C$ to $500^{\circ}C$. The V-I characteristics of the SiC+40vol.%$ZrB_2$ composite had a linear shape. Therefore, it is considered that the SiC+40vol.%$ZrB_2$ composite containing the most outstanding mechanical properties, high resistance temperature coefficient and PTCR characteristics among the sintered compacts can be used as an energy friendly ceramic heater or electrode material through SPS.

• Toxicological Research
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• 제12권1호
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• pp.17-20
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• 1996

The effect of Fumonisin B1, a mycotoxin produced by Fusarium moniliforme on bacterial viruses P1 and Lambda, was investigated by the virus plaque assay. Fumonisin B1 inhibited the P1 viral multiplication in the concentration range from $100{\mu}g$/ml to $400{\mu}g$/ml. The inhibition was Fumonisin B1 concentration-dependent. Another bacterial virus Lambda multiplication was also inhibited by lower concentration of Fumonisin B1 ($10{\mu}g$/ml~$50{\mu}g$/ml). This inhibition was dependent on Fumonisin B1 and on virus-Fumonisin B1 reaction time. Sensitivity of bacteriophage Lambda to Fumonisin B1 was higher than that of P1 virus. Lambda vital DNA was treated in vitro with Fumonisin B1 at various concentration. Significant DNA fragmentation by Fumonisin 191 was observed in the agarose gel electrophoresis. Lambda viral DNA was partially digested even in the Fumonisin B1 $10{\mu}g$ and the level of its fragmentation was dependent on Fumonisin B1 amount up to $30{\mu}g$ per assay.

• 한국식품위생안전성학회지
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• 제21권3호
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• pp.159-163
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• 2006

건포류 86건에 대한 시험 결과, 37건(43.0%=37/86)에서 Bacillus spp가 18건(20.9%=18/86)에서 B. cereus가 분리되었다. 분리 동정된 37주는 B. cereus 48.6%(18/37), B. mycoides 13.5%(5/37), B. coagulus 5.4%(2/37). B. firmus 5.4%(2/37), B. circulus 2.7%(1/37), B. stearothermophilus 2.7%(1/37), B. pumilus 2.7%(1/37), E. spp. 8.1%(3/37), 그리고 Brebacillus brevis 10.8%(4/37) 등으로 나타나 식중독균의 일종인 B. cereus가 가장 많이 나타나 주의를 요할 것으로 사료된다.

• 한국통신학회논문지
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• 제26권10B호
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• pp.1470-1474
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• 2001

8B/10B 선로부호를 채택한 기가비트 이더넷 PCS 수신측에서는 동기부의 바이트 동기획득과 수신부의 디코딩을 위해 Running Disparity(RD) 에러인 데이터열을 검출해야 한다. 기존의 RD 에러 검출 방법은 직렬 입력 비트에서 RD 에러를 검출하였으나 제안하는 RD 에러 검출 방법은 125MHz 속도의 10비트 데이터열을 받아 4비트열과 6비트열로 나누어 바이트 클럭에 따라 RD를 계산하고 계산된 이전의 RD값과 현재의 RD값을 비교하며 RD 위반 에러 데이터를 검출한다. 이는 기존의 RD 에러 검출 방법이 비트 클럭과 니블 클럭에 따라 RD 에러를 검출하기 때문에 야기되는 초고속 처리에 대한 한계를 해결한 것이며 기가비트 이더넷에 적합한 새로운 RD 에러 검출 방법이다.

• 약학회지
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• 제44권6호
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• pp.505-510
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• 2000

The synthesis of pentahydroindanoisoquinoline (4) compound has been achieved via the cyclization of 2-(N-benzylamino)-5,6-difluoro-1-indanol (10a, 10b), which was prepared by condensation and reduction of 2-amino-1-indanol and benzaldehyde in ethanol. The stereochemistry of $H_{6a}$ and $H_{11b}$ of 9,10-difluoro-5,6,6a,7,11b-pentahydroindano[2,1-c]isoquinoline (4) was the trans B/C ring fusion.

• 대한기계학회논문집B
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• 제23권3호
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• pp.311-319
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• 1999

The thermal conductivity ${\lambda}_b$, thermal diffusivity ${\alpha}_b$ of the thin black paint layer sprayed on solid surface and absorptivity a for laser beam are measured by applying a non-contact measurement method of the thermophysical properties of solids. The values of a=0.67, ${\lambda}_b=1.45W/mK$ and ${\alpha}_b=1.24{\times}10^{-6}m^2/s$ are obtained for the sprayed lay~ thickness $z_b{\fallingdotseq}40\;{\mu}m$. Furthermore, for the $z_b{\fallingdotseq}24\;{\mu}m$ thick layers which arc formed by rubbing with a glass rod after spraying, the values of a=0.73, ${\lambda}_b=1.85W/mK$. and ${\alpha}_b=1.09{\times}10^{-6}m^2/s$ are obtained. It is also shown that the present thermal diffusivity ${\alpha}_b$ for $z_b{\fallingdotseq}40\;{\mu}m$ Is about 30~80% larger than those obtained by Araki et al. for the thicker layer $z_b{\fallingdotseq}150{\sim}248\;{\mu}m$. This method could be applied to the measurement of thermophysical properties of thin layer on solids.

• 동의생리병리학회지
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• 제23권1호
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• pp.63-75
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• 2009

The aim of this study was to elucidate the antimelanogenic effect of Dokhwalkisaeng-tang(Duohujisheng-tang) in B16F10 melanoma cells. Dokhwalkisaeng-tang(DKT) was used to develop the effective prescription of inhibition of melanin production. We determined inhibitory effects of DKT on melanin-release, melanin production, and tyrosinase activity in B16F10 melanoma cells. And to explicate the action-mechanism of DKT, melanin-related gene expressions were determined using RT-PCR and real time RT PCR technique in B16F10 melanoma cells. DKT inhibited melanin-release, melanin production in B16F10 melanoma cells considerably. DKT inhibited tyrosinase activity in vitro and in B16F10 melanoma cells. DKT inhibited the expression of tyrosinase, TRP-1, TRP-2 in B16F10 melanoma cells. DKT inhibited the expression of PKA, PKC, MMP-2 and MITF in B16F10 melanoma cells. On the other hand, DKT increased the expression of ERK-1, ERK-2, AKT-1 in B16F10 melanoma cells. From these results, we propose that DKT may have effect on the antimelanogenesis.