• The Korean Journal of Physiology and Pharmacology
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• v.10 no.5
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• pp.243-249
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• 2006

The effect of genistein, widely used as a specific tyrosine kinase inhibitor, on rat brain Kv1.5 channels which were stably expressed in Chinese hamster ovary cells was investigated using the whole-cell patch-clamp technique. Genistein inhibited Kv1.5 currents at +50 mV in a concentration-dependent manner, with an $IC_{50}$ of $54.7{\pm}8.2\;{\mu}M$ and a Hill coefficient of $1.1{\pm}0.2$. Pretreatment of Kv1.5 with protein tyrosine kinase inhibitors ($10\;{\mu}M$ lavendustin A and $100\;{\mu}M$ AG1296) and a tyrosine phosphatase inhibitor ($500\;{\mu}M$ sodium orthovanadate) did not block the inhibitory effect of genistein. The inhibition of Kv1.5 by genistein showed voltage-independence over the full activation voltage range positive to 0 mV. The activation (at +50 mV) kinetics was significantly delayed by genistein: time constant for an activation of $1.4{\pm}0.2$ msec under control conditions and $10.0{\pm}1.5$ msec in the presence of $60\;{\mu}M$ genistein. Genistein also slowed the deactivation of the tail currents, resulting in a crossover phenomenon: a time constant of $11.4{\pm}1.3$ msec and $40.0{\pm}4.2$ msec under control conditions and in the presence of $60\;{\mu}M$ genistein, respectively. Inhibition was reversed by the application of repetitive depolarizing pulses, especially during the early part of the activating pulse. These results suggest that genistein directly inhibits Kv1.5 channels, independent of phosphotyrosine-signaling pathway.

• The Journal of the Institute of Internet, Broadcasting and Communication
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• v.18 no.6
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• pp.107-112
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• 2018

Shielding effectiveness (SE) improvement with EMI shield layers fabricated by conformal spray coating system was studied. Silver or Nickel powder filled acrylic resin were sprayed on the samples. We compared the performance with the viscosity of 400 cPs and 100 cPs cases. The thickness range of the coating layer was 20 to 50 um for the silver, 60 to 120 um for the nickel. The shielding effectiveness was measured by ASTM D4935 using coaxial type TEM-cell. The silver-filled resin showed much better performance than that of the nickel-filled resin. The shielding effectiveness increased almost proportional to the thickness of the coating layers until being saturated around 63 dB for the silver-layer or around 34 dB for the nickel-layer. The best performance measured in this study was the shielding effectiveness of 63 dB with $35{\mu}m-thick$ of silver-layer.

• Asian-Australasian Journal of Animal Sciences
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• v.32 no.4
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• pp.527-532
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• 2019

Objective: Phosphorous (P) sources with greater bioavailability might increase animal production efficiency and decrease environmental pollution. The objective of current study was to determine animal performance, nutrient digestibility, blood metabolites and fecal P concentration in finishing lambs fed a diet with either di-calcium phosphate (DCP) or di-ammonium phosphate (DAP) as a P source. Methods: Twelve 4-month-old male lambs (initial body weight $24.87{\pm}3.4kg$) were randomly allocated to a diet with either DCP or DAP (~261 g/kg of total diet P) fed ad libitum for 93 days. Diets were iso-nitrogenous and iso-energetic and had same calcium (Ca) and P concentrations. Results: The DAP contained 19.7 g/kg of dry matter (DM) Ca, 185.4 g/kg DM P and 14,623 ppm fluorine, while DCP contained 230.3 g/kg DM Ca, 195.2 g/kg DM P and 1,039 ppm fluorine. The diet with DAP contained 60 ppm fluorine while the diet with DCP contained 13 ppm fluorine. Lambs fed the diet with DAP tended to have a greater daily DM intake compared to those fed diet with DCP (p = 0.09). Lambs fed DAP had greater plasma P concentration and alkaline phosphatase activity ($p{\leq}0.01$) compared with lambs fed DCP. Dry matter and organic matter digestibility of the diets were similar between two treatments at days 60 and 90, while they were greater in lambs fed DCP (p<0.05) at day 30 of the trial. Feeding DAP increased P digestibility (58.7% vs 50.2%; p<0.05) and decreased fecal P concentration in lambs compared with feeding DCP (3.1 vs 3.8 g/kg DM; p<0.05). Conclusion: Providing ~261 g/kg of total diet P as DAP in the diet of finishing lambs improved the bioavailability of P in the body and decreased excretion of P in feces without affecting lamb performance.

• Advances in nano research
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• v.15 no.4
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• pp.355-366
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• 2023

Biological corrosion, a crucial aspect of metal degradation, has received limited attention despite its significance. It involves the deterioration of metals due to corrosion processes influenced by living organisms, including bacteria. Soil represents a substantial threat to pipeline corrosion as it contains chemical and microbial factors that cause severe damage to water, oil, and gas transmission projects. To combat fouling and corrosion, corrosion inhibitors are commonly used; however, their production often involves expensive and hazardous chemicals. Consequently, researchers are exploring natural and eco-friendly alternatives, specifically nano-sized products, as potent corrosion inhibitors. This study aims to environmentally synthesize silver nanoparticles using an extract from Lagoecia cuminoides L and evaluate their effectiveness in preventing biological corrosion of buried pipes in soil. The optimal experimental conditions were determined as follows: a volume of 4 ml for the extract, a volume of 4 ml for silver nitrate (AgNO3), pH 9, a duration of 60 minutes, and a temperature of 60 degrees Celsius. Analysis using transmission electron microscopy confirmed the formation of nanoparticles with an average size of approximately 28 nm, while X-ray diffraction patterns exhibited suitable peak intensities. By employing the Scherer equation, the average particle size was estimated to be around 30 nm. Furthermore, antibacterial studies revealed the potent antibacterial activity of the synthesized silver nanoparticles against both aerobic and anaerobic bacteria. This property effectively mitigates the biological corrosion caused by bacteria in steel pipes buried in soil.

• Microbiology and Biotechnology Letters
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• v.20 no.5
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• pp.519-526
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• 1992

The gene coding for urease of alkalophilic Bacillus pasteurii had been cloned in Escherichia coli previously. The urease protein was purified 63.1-fold by TEAE-cellulose, DEAE-Sephadex A-50, Sephadex G-150 and Sephadex G-200 chromatographies with a 7.3% yield from the sonicated fluid of the E. coli HB1Ol(pBUll) encoding B. pasteurii urease gene. The ureases of E. coli (pBUll) and B. pasteurii possessed as a $K_m$ for urea, 42.1 mM and 40.4 mM, respectively. They hydrolyzed urea with $V_{max}$ of 86.9$\mu$mol/min and 160$\mu$mol/min, respectively. Both ureases were composed with four subunits (Mrs 67,000) and a subunit (Mr 20,000). The molecular weight of both native enzymes was Mr 280,OOO$pm$10,000 determined by gel filtration chromatography and Coomassie blue staining of the subunits. The optimal reaction pH of both ureases were pH 7.5. The ureases were stabled in pH 5.5-10.5. The optimal reaction temperature of both ureases were $60^{\circ}C$, and the ureases were stable for an hour at $50^{\circ}C$, 40min at $60^{\circ}C$ and 10 min at $70^{\circ}C$ The activity of both enzymes were inhibited completely by $Ag^{2+}$, $Hg^{2+}$, $Zn^{2+}$, $Cu^{2+}$, and were inhibited 60% by CoH, 30% by $Fe^{2+}$ and 10% by $Pb^{2+}$. However it was increased by the addition of $Sn^{2+}$, $Mn^{2+}$, $Mg^{2+}$ at concentration of $1{\times}10^{-3}$M. Both ureases were inhibited completely by p-CMB and acetohydroxamic acid. The urease expressed in E. coli (pBU11) was inhibited 70% by SDS. The urease of B. pasteurii was inhibited 40% by hydroxyurea, whereas the recombinant urease of E. coli strain was inhibited 17%. Both enzymes were not inhibited by cyclohexanediaminetetraacetic acid (CDTA) and ethylendiaminetetraacetic acid (EDTA).

• Proceedings of the KIEE Conference
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• 1999.07d
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• pp.1756-1758
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• 1999

As new gas sensing material with high cata activity for NO decomposition and for CO oxid $LaFeO_3$ thin films with different thicknesses fabricated by the R.F. magnetron sputtering m on an $Al_2O_3$ substrates with Ag electrodes. The sensing characteristics of the $LaFeO_3$ thin films studied as a function of annealing temperature film thickness. The thin film annealed at showed the highest sensitivity of 110% for CO 60% for NO.

• BMB Reports
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• v.40 no.5
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• pp.814-824
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• 2007

Liver cirrhosis (LC) is defined as comprising diffuse fibrosis and regenerating nodules of the liver. The biochemical and anatomical dysfunction in LC results from both reduced liver cell number and portal vascular derangement. Although several studies have investigated dysregulated genes in cirrhotic nodules, little is known about the genes implicated in the pathophysiologic change of LC or about their relationship with the degree of decompensation. Here, we applied cDNA microarray analysis using 38 HBsAg-positive LC specimens to identify the genes dysregulated in HBV-associated LC and to evaluate their relation to disease severity. Among 1063 known cancer- and apoptosis-related genes, we identified 104 genes that were significantly up- (44) or down- (60) regulated in LC. Interestingly, this subset of 104 genes was characteristically correlated with the degree of decompensation, called the Pugh-Child classification (20 Pugh-Child A, 10 Pugh-Child B, and 8 Pugh-Child C). Patient samples from Pugh-Child C exhibited a distinct pattern of gene expression relative to those of Pugh-Child A and B. Especially in Pugh-Child C, genes encoding hepatic proteins and metabolizing enzymes were significantly down-regulated, while genes encoding various molecules related to cell replication were up-regulated. Our results suggest that subsets of genes in liver cells correspond to the pathophysiologic change of LC according to disease severity and possibly to hepatocarcinogenesis.

• Journal of the Microelectronics and Packaging Society
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• v.18 no.3
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• pp.67-74
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• 2011

Keys to high wiring density semiconductor packages include flip-chip bonding and build-up substrate technologies. The current issues are the establishment of a fine pitch flip-chip bonding technology and a low coefficient of thermal expansion (CTE) substrate technology. In particular, electromigration and thermomigration in fine pitch flipchip joints have been recognized as a major reliability issue. In this paper, electromigration and thermomigration in Cu/Sn-3Ag-0.5Cu (SAC305)/Cu flip-chip joints and electromigration in Cu/In/Cu flip chip joints are investigated. In the electromigration test, a large electromigration void nucleation at the cathode, large growth of intermetallic compounds (IMCs) at the anode, a unique solder bump deformation towards the cathode, and the significantly prolonged electromigration lifetime with the underfill were observed in both types of joints. In addition, the effects of crystallographic orientation of Sn on electromigration were observed in the Cu/SAC305/Cu joints. In the thermomigration test, Cu dissolution was accelerated on the hot side, and formation of IMCs was enhanced on the cold side at a thermal gradient of about $60^{\circ}C$/cm, which was lower than previously reported. The rate of Cu atom migration was found comparable to that of electromigration under current conditions.

• Journal of the Korean Institute of Electrical and Electronic Material Engineers
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• v.20 no.9
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• pp.766-770
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• 2007

In this study, in order to develop low temperature sintering ceramics for multilayer piezoelectric actuator, $0.07Pb(Mn_{1/3}Nb_{2/3})O_3-xPb(Ni_{1/3}Nb_{2/3})O_3-(0.93-x)Pb(Zr,Ti)O_3$ ceramics system were fabricated using $Li_2CO_3-Bi_2O_3-CuO$ sintering aids and the specimens were sintered at $930^{\circ}C$. Thereafter, their piezoelectric and dielectric characteristics were investigated according to the amount of PNN substitution. At 9 mol% PNN substitution, density, electromechanical coupling factor ($k_p$), dielectric constant, mechanical quality factor ($Q_m$) and piezoelectric constant ($d_{33}$) showed the optimum value of $7.86g/cm^3$, 0.60, 1640, 1323 and 387 pC/N, respectively. It is considered that these values are suitable for piezoelectric divece application such ad multilayer piezoelectric actuator and ultrasonic vibrator with pure Ag internal electrode.

• The Journal of Korean Academy of Prosthodontics
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• v.36 no.3
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• pp.514-523
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• 1998

The purpose of this study was to compare the wear characteristics of Type III Gold Alloy (Degular C : Degussa AG), VMK 95 (Vita Zahnfabrik), Vitadur Alpha (Vita Zahnfabrik), IPS Empress (Ivoclar-Vivadent) and Targis (Ivoclar- Vivadent). Ten samples of each material were abraded against enamel of extracted incisors for 160,000 cycles on the wear machine. The depth of wear scars on enamel was analized with profilometer (Alpha-step 200;Tencor). And the wear of material specimen was determined with micrometer (PB-IB;Mitutoyo Co. Japan). The results obtained were as follows : 1. Type III gold alloy ($2.47{\mu}m$) and Targis ($5.89{\mu}m$) caused less wear of enamel specimens compared to VMK 95 ($75.59{\mu}m$), IPS Empress ($78.60{\mu}m$) and Vitadur Alpha ($78.89{\mu}m$) (p<0.05). 2. The wear of material specimen when opposing enamel was the lowest in type III gold alloy ($3.0{\mu}m$), followed by Targis ($69.8{\mu}m$), IPS Empress ($148.4{\mu}m$). VMK 95 ($298.0{\mu}m$) and Vitadur Alpha ($300.8{\mu}m$ exhibited the most severe wear against enamel (p<0.05).