• The Journal of Korean Institute of Communications and Information Sciences
• /
• v.28 no.3A
• /
• pp.179-184
• /
• 2003

In this paper, an asymmetric topology of MMIC SPDT switch was proposed to increase the isolation in the receiving path and decrease the insertion loss with higher P1dB in the transmitting path for the ISM band. This SPDT switch was implemented with 0.5㎛ GaAs MESFETs processed by ETRI for the IDEC MPW project. For the receiving path the measured insertion losses were 1.518dB at 3GHz and 1.777dB at 5.75GHz and the isolations were 38.474dB at 3GHz and 29.125dB at 5.75GHz. For the transmitting path the insertion losses were 0.916dB at 3GHz and 1.162dB at 5.75GHz and the isolations were 23.259dB at 3GHz and 16.632dB at 5.75GHz. Compared to the symmetric topology the isolations of the receiving path for the asymmetric one were improved by 15.9dB at 3GHz and 11.9dB at 5.75GHz and its insertion loss was increased by about 0.6dB. In addition, P1dB of 21.5 dBm for the transmitting path was obtained, which is increased by 3.86dB compared to the symmetric one.

• Journal of the Korean Magnetic Resonance Society
• /
• v.17 no.1
• /
• pp.24-29
• /
• 2013

The structural characteristics of 4-coordinate $BO_4$ [B(1)] and 3-coordinate $BO_3$ [B(2)] groups in $BiB_3O_6$ were studied by $^{11}B$ magic angle spinning (MAS) and single-crystal nuclear magnetic resonance (NMR) spectroscopy. The spin-lattice relaxation time in the laboratory frame, $T_1$, for $^{11}B$ decreased slowly with increasing temperature, whereas the spin-lattice relaxation times in the rotating frame, $T_{1{\rho}}$, for B(1) and B(2), which differed from $T_1$, were nearly constant. Further, $T_{1{\rho}}$ for B(1) and B(2) showed very similar trends, although the $T_{1{\rho}}$ value of B(2) was shorter than that of B(1). The 3-coordinate $BO_3$ and 4-coordinate $BO_4$ were distinguished by $^{11}B$ MAS NMR spectrum and $T_{1{\rho}}$.

• Journal of Life Science
• /
• v.32 no.11
• /
• pp.833-840
• /
• 2022

Chronic inflammation has been shown to be closely associated with tumor development and progression. Nuclear factor kappa B (NF-κB) is composed of a family of five transcription factors. NF-κB signaling plays a crucial role in the inflammatory response and is often found to be dysregulated in various types of cancer, making it an attractive target in cancer therapeutics. In this study, CDC-like kinase 3 (CLK3) was identified as a novel kinase that regulates the NF-κB signaling pathway. Our data demonstrate that CLK3 inhibits the canonical and non-canonical NF-κB pathways. Luciferase assays following the transient or stable expression of CLK3 indicated that this kinase inhibited NF-κB activation mediated by Tumor necrosis factor-alpha (TNFα) and Phorbol 12-myristate 13-acetate (PMA), which are known to activate NF-κB signaling via the canonical pathway. Consistent with data on the ectopic expression of CLK3, CLK3 knockdown using shRNA constructs increased NF-κB activity 1.5-fold upon stimulation with TNFα in HEK293 cells compared with the control cells. Additionally, overexpression of CLK3 suppressed the activation of this signaling pathway induced by NF-κB-inducing kinase (NIK) or CD40, which are well-established activators of the non-canonical pathway. To further examine the negative impact of CLK3 on NF-κB signaling, we performed Western blotting following the TNFα treatment to directly identify the molecular components of the NF-κB pathway that are affected by this kinase. Our results revealed that CLK3 mitigated the phosphorylation/activation of transforming growth factor-α-activated kinase 1 (TAK1), inhibitor of NF-κB kinase alpha/beta (IKKα/α), NF-κB p65 (RelA), NF-κB inhibitor alpha (IκBα), and Extracellular signal-regulated kinase 1/2-Mitogen-activated protein kinase (ERK1/2-MAPK), suggesting that CLK3 inhibits both the NF-κB and MAPK signaling activated by TNFα exposure. Further studies are required to elucidate the mechanism by which CLK3 inhibits the canonical and non-canonical NF-κB pathways. Collectively, these findings reveal CLK3 as a novel negative regulator of NF-κB signaling.

• Journal of the Korean Crystal Growth and Crystal Technology
• /
• v.14 no.3
• /
• pp.123-128
• /
• 2004

Both photoluminescence and the long-phosphorescent properties for $SrAl_2O_4$ : Eu$^{+2}$, $Dy^{+3}$ phosphor powder synthesized by the solid phase reaction were investigated as a function of $B_2O_3$ composition (0-10 wt%). The highest emission wavelength (520nm) of photoluminescence spectra was not affected by $B_2O_3$concentration. The highest emission intensity was obtained by the concentration of 3 wt% $B_2O_3$.After the removal of the Xenon lamp excitation (360nm), also, the excellent long-phosphorescent property of the phosphors was obtained by the concentration of 3 wt% $B_2O_3$ although the decay times for all phosphors decreased exponentially.

• Food Science and Preservation
• /
• v.30 no.1
• /
• pp.98-108
• /
• 2023

The purpose of this study was to determine the vitamin B₁ and B₃ contents in 135 Korean domestic foods using high performance liquid chromatography (HPLC). The Standard Reference Material (SRM) 3233 and in-house control (grain, whole wheat and flour mixture) were used for quality control/assurance. As a result, vitamin B₁ was only detected in 54 of the 135 foods, ranging from 0.019 mg/100 g to 28.218 mg/100 g. Among the foods tested, the vitamin B₁ content was highest in ramen powder (28.218 mg/100 g) and lowest in boiled jjolmyeon (0.019 mg/100 g). In contrast, vitamin B₃ was detected in 108 of the 135 foods, ranging from 0.077 mg/100 g to 32.412 mg/100 g. We found that the vitamin B₃ content was highest in beef liver (32.412 mg/100 g) and lowest in boiled chicken heart (0.077 mg/100 g). The results of this study will be used as a nutritional database for the update of the Korean food composition table and will hence contribute to improving public health.

• Journal of Powder Materials
• /
• v.9 no.5
• /
• pp.352-358
• /
• 2002

The effects of boron or manganese added as $B_4C$, Mn, $TiB_2$, B on TiC-30vo1.%$Ni_3Al$ cermet sintered at 1380 and $1400^{\circ}C$ for 1 hour, were examined in relation with shrinkage, relative density, microstructure, lattice parameter, hardness and fracture toughness ($K_{IC}$). The results are summarized as follows: 1) The highest shrink-age showed about 30.5% in the specimen added B$_4$C and the maximum relative density was about 99% in the specimen added $TiB_2$; 2) The grains of TiC were grown during sintering and made the surrounding structure by adding boron and manganese. The largest grain size showed about $2.8\mutextrm{m}$ in the specimen with boron sintered at $1400^{\circ}C$;3) The lattice parameter of TiC was about $4.325\AA$ and $Ni_3Al$ about $3.592\AA$ by adding other elements; 4) The highest hardness was about $1100kgf/\textrm{mm}^2$ in the specimen with B4C; 5) The fracture toughness ($K_{IC}$) showed about $15MNm^{-3/2}$ in the specimen added $TiB_2$.

• Korean journal of food and cookery science
• /
• v.22 no.4 s.94
• /
• pp.458-467
• /
• 2006

This study was carried out to determine the functional works and basic ingredients of Sagoonja-Tang on white pan bread. The -experimental groups consisted of 6% mixtures of five(Ed- confirm the number) kinds powders, : B1 for Sagoonja-Tang powder, B2 for Panax ginseng, B3 for Poria cocos, Koidz, B4 for Atractylodes macrocephala, and B5 for Glycyrrhiza uralensis Fisch. The volume of white pan bread somewhat decreased after adding the ingredients, and the volume differences in order from highest to lowest, were white pan bread control>B2>B3>B4>B1>B5. For white pan bread, pH of control, B3, and B5 decreased on the 2nd day during storage, but increased on the 4th and 7th days. In the texture analyses of white pan bread, B4 and B5 showed a higher degree of hardness than that of control, while B2, and B3 were the lowest. In sensory test, the overall acceptability of regular white pan bread in order from highest to lowest was control>B3>B2>B1 ${\cdot}$ B5>B4.

• Journal of Korean Neurosurgical Society
• /
• v.63 no.6
• /
• pp.707-716
• /
• 2020

Objective : The function of B7H3, a member of the B7 family of proteins, in neuroblastoma (NB) remains poorly characterized. Here we examine the expression pattern of B7H3 in clinical NB specimens and characterize the phenotype of B7H3 knock-down in NB cell line. Methods : Immunohistochemical (IHC) staining was carried out to assess the expression of B7H3 in clinical NB specimens. Survival association was analyzed using five Gene Expression Omnibus (GEO) datasets (GSE85047, GSE45480, GSE62564, GSE16476, GSE49710). Clonogenic survival and flow cytometry were performed after B7H3 knockdown to assess the cellular proliferation and cell survival in vitro. Impact of B7H3 silencing on NB growth was examined in vivo using the SH-SY5Y xenograft model. Results : On IHC staining, B7H3 was widely expressed in clinical NB specimens. Analysis of the transcriptional profiles of five GEO datasets clinically annotated NB specimens revealed that decreased B7H3 expression was associated with improved overall survival. B7H3 knockdown suppressed the proliferation of the SH-SY5Y NB model in vitro and in vivo. Cell cycle analysis revealed that B7H3 silencing induced G1/S arrest. This arrest was associated with the suppression of E2F1 expression and induction of Rb expression. Conclusion : Our results demonstrate that B7H3 expression correlate with clinical survival in NB patients. Preliminary studies suggest that B7H3 may mediate the G1/S transition.

• Korean Journal of Clinical Laboratory Science
• /
• v.52 no.1
• /
• pp.69-77
• /
• 2020

The tumor suppressor gene, p53, is inactivated in the human hepatocellular carcinoma cells line, Hep3B. Berberine has been reported to inhibit the proliferation of cancer cells. This study examined whether apoptosis was induced in berberine-treated Hep3B cells and observed the association between apoptosis and the expression of p53 and DNA methyltransferase (DNMT). The cell viability was measured using an MTT assay. Apoptosis of Hep3B was measured using annexin V flow cytometry. Berberine-treated cells were examined for their DNMT enzymatic activity, mRNA expression, and protein synthesis. The p53 levels were examined by Western blot analysis. The berberine treatment resulted in increased Hep3B cell death and apoptosis in a time- and dose-dependent manner. The DNMT3b activity, mRNA expression, and protein levels all decreased after the berberine treatment. In contrast, the p53 protein levels increased with a concomitant decrease in DNMT3b. No change in the expression of ERK was observed, but the P-ERK levels decreased in a dose dependent manner. These results indicate that a treatment of Hep3B cells with berberine can reduce the expression of DNMT3b, leading to an increase in the tumor suppressant gene p53 and an increase in cell apoptosis. This shows that berberine can effectively suppress the proliferation of liver cancer cells.

• Journal of Life Science
• /
• v.16 no.3 s.76
• /
• pp.522-526
• /
• 2006

To investigate the effects of UV-B on fatty acid composition, lipid peroxidation and biochemical defense responses of plant, kidney bean (Phaseolus vulgaris L.) was subjected to enhanced UV-B irradiation [daily dose : 0.02.(No UV-B) and 11.36 (enhanced UV-B) $kJ\;m^{-2};UV-B_{BE}$] for 3 weeks. UV-B drastically inhibited both height and dry weight of kidney bean. The content of malondialdehyde significantly increased by about 50% after 3 weeks of UV-B irradiation. The ratio of unsaturated to saturated fatty acids of kidney bean was increased by UV-B irradiation. Three major polyamines of kidney bean leaves : putrescine, spermidine and spermine, were observed. All of the polyamine contents were increased with UV-B irradiation. These results suggested that enhanced UV-B radiation caused oxidative stress on lipids and biochemical protection responses might be activated to prevent from damaging effects of oxidative stress generated by UV-B irradiation.