• ETRI Journal
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• v.38 no.4
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• pp.675-684
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• 2016

This paper demonstrates the effect of fluoride-based plasma treatment on the performance of $Al_2O_3/AlGaN/GaN$ metal-insulator-semiconductor heterostructure field effect transistors (MISHFETs) with a T-shaped gate length of $0.20{\mu}m$. For the fabrication of the MISHFET, an $Al_2O_3$ layer as a gate dielectric was deposited using atomic layer deposition, which greatly decreases the gate leakage current, followed by the deposition of the silicon nitride layer. The silicon nitride layer on the gate foot region was then selectively removed through a reactive ion etching technique using $CF_4$ plasma. The etching process was continued for a longer period of time even after the complete removal of the silicon nitride layer to expose the $Al_2O_3$ gate dielectric layer to the plasma environment. The thickness of the $Al_2O_3$ gate dielectric layer was slowly reduced during the plasma exposure. Through this plasma treatment, the device exhibited a threshold voltage shift of 3.1 V in the positive direction, an increase of 50 mS/mm in trans conductance, a degraded off-state performance and a larger gate leakage current compared with that of the reference device without a plasma treatment.

• Current Photovoltaic Research
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• v.5 no.3
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• pp.89-94
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• 2017

We have examined the issues on the measurement of bifacial photovoltaic(PV) devices that should be considered in order to ensure a measurement accuracy beyond a certain level and the comparability between the bifacial PV devices. Based on the results of various experiments and previous studies, solutions for these measurement issues are suggested. The most significant technical issues in the performance measurement of the bifacial PV devices are 1) elimination of the effect due to the light reflection on the sample holder surface and 2) the measurement of the expected power generation gain in outdoor operation. The effect due to the light reflection on the sample holder surface can be eliminated by using an anti-reflective sample holder. In case of a reflective sample holder, if the bifacial device have a linear characteristic with respect to the irradiance of incident light, it has been confirmed (through some previous studies and additional experiment) that exact measurement results can be obtained by the correction of the measurement data. In addition, it was also confirmed that the expected power generation gain in the outdoor operation can be obtained by three different methods along with the basic concepts of the bifaciality coefficient, the albedo, and the effective front irradiance.

• Proceedings of the Korean Society of Developmental Biology Conference
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• 2003.10a
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• pp.105-105
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• 2003

In previous reports, pVPSV.IGR2.1 transgenic mouse were described that brain tumor and lymphoma by reason of Vasopressin-SV40 T antigen. In this study, we produced pVPSV.IGR3.6 transgenic mouse that used pVPSV.IGR3.6 vector. Expression of transgene was vary different in transgenic mouse. We obtained 6 transgenic mouse line, moreover they had died at the age of 2-6 weeks without transmitting the transgene to their offspring, and had tumorigenesis on same location with pVPSV.IGR2.1 transgenic mouse. Only a founder mouse was investigated for expression of fusion gene. Here we extended this transgenic approach to the study of tumor progression. From the mouse, we confirmed brain tumor cell, after then cultured for investigate characterization. In this report, we demonstrate that reduction of survival rate in transgenic mouse fused vasopressin gene length, acquisition of brain tumor cell, composition with astrocyte cells and neuronal cells. Finally, cells had no change with increase of passage.

• BMB Reports
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• v.37 no.1
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• pp.107-113
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• 2004

Since the completion of the genome project of the nematode C. elegans in 1998, functional genomic approaches have been applied to elucidate the gene and protein networks in this model organism. The recent completion of the whole genome of C. briggsae, a close sister species of C. elegans, now makes it possible to employ the comparative genomic approaches for identifying regulatory mechanisms that are conserved in these species and to make more precise annotation of the predicted genes. RNA interference (RNAi) screenings in C. elegans have been performed to screen the whole genome for the genes whose mutations give rise to specific phenotypes of interest. RNAi screens can also be used to identify genes that act genetically together with a gene of interest. Microarray experiments have been very useful in identifying genes that exhibit co-regulated expression profiles in given genetic or environmental conditions. Proteomic approaches also can be applied to the nematode, just as in other species whose genomes are known. With all these functional genomic tools, genetics will still remain an important tool for gene function studies in the post genome era. New breakthroughs in C. elegans biology, such as establishing a feasible gene knockout method, immortalized cell lines, or identifying viruses that can be used as vectors for introducing exogenous gene constructs into the worms, will augment the usage of this small organism for genome-wide biology.

• BMB Reports
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• v.34 no.1
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• pp.80-84
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• 2001

The human papillomavirus E7 protein can form a specific complex with a retinoblastoma tumor suppressor gene product (p105-Rb) that results in the release of the E2F transcription factor, which is critical for the growth-deregulation and transforming properties of the viral E7 oncoprotein. In an attempt to apply interaction between the E7 oncoprotein and a target cellular protein Rb for an in vitro screening system for drugs against human papillomavirus infection, we primarily investigated the E7Rb binding through a pull down assay and enzyme-linked immunosorbent assay. The pull down assay showed that both glutathione S-transferase-tagged E7 and His-tagged E7 immobilized on resins specifically produced complexes with bacterially expressed Rb in a dose-dependent manner, as determined by immunoblot analyses. This result coincided with that of an enzyme-linked immunosorbent assay, which is a useful system for the mass screening of potential drugs. Taken together, this screening system (based on the interaction between E7 and Rb) can be a promising system in the development of drugs against cervical cancers caused by human papillomavirus infection.

• 한국정보디스플레이학회:학술대회논문집
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• 2003.07a
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• pp.722-725
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• 2003

In AC plasma display, it is very important to quantify the wall voltage induced by the wall charge accumulated on the dielectric surface. If we know the quantities of the wall voltage in each period of every sequence; reset period, address period and sustain period, then it helps us to design the optimal driving waveform for high efficiency plasma display. We develop a new method to measure the wall voltage with VDS (Versatile Driving Simulator) system. From this method the wall voltage induced by a wall charge profiles just after the reset discharge of every cells in plasma display panel can be investigated and analyzed successfully. It is noted that the wall voltage profiles are influenced by the space charge and then they are stabilized as time goes by. It is also noted that both the remaining wall charge at the previous sequence and space charges contribute to wall voltage quantities just after the reset discharge. It is noted that the wall charges contribute dominantly after a few hundreds microseconds, while the space charges have been decayed within 100 ${\mu}s$ just after the reset discharge.

• BMB Reports
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• v.36 no.2
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• pp.237-242
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• 2003

Hepatic lipase is a key enzyme that is involved in HDL-C metabolism. The goal of this study was to find out the frequency of the hepatic lipase C514T polymorphism, and evaluate its relationship with plasma HDL-C levels and coronary artery disease (CAD) in Koreans. Two hundred and twenty four subjects with no previous history of lipid-lowering therapy, 118 patients with significant CAD, and 106 controls were examined with respect to their genotypes, lipid profiles, and other risk factors for CAD. The frequency of the -514T allele was 0.37 in men and 0.35 in women, which were higher than the frequency that was reported in Caucasians, but lower than the frequency that was reported in African-Americans. The -514T allele was associated with significantly higher HDL-C levels in women. After controlling for age, gender, BMI, DM, and smoking, the non-CC genotype was significantly associated with HDL-C levels, and explained 6% of the HDL-C variation in this study. When the genotypes-distribution was compared between the CAD and non-CAD patients, the hepatic lipase C-514T polymorphism was not associated with the presence of CAD. Koreans have a higher frequency of the hepatic lipase gene 514T allele than Caucasians, and the -514T allele is associated with higher plasma HDL-C levels in Korean women, and perhaps non-smoking men. However, our data does not suggest an association between the polymorphism and an increased risk of CAD.

• Proceedings of the Korean Society of Applied Pharmacology
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• 1995.04a
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• pp.108-108
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• 1995

Pharmacokinetic studies on time-course of blood levels, tissue distribution, and excretion of G009, a potential hepatoprotective agent, were performed in male rats after a single oral dose(20mg/kg) of $\^$14/C-labelled G009. The radioactivity concentrations in plasma during 0～3 hours are low, but subsequently increase to a maximum at 12 hours after dosing. $\^$14/C-G009 was well distributed to all tissue. Tissue concentration profiles of radioactivity vary among tissues on time-course after administration. G009(single oral dosage) was distributed and/or absorbed at gastric intestines and excretional organs for initial time of 0-7 hours, and distributed to most tissue at 12-24 hours. In special, the concentration of radioactivity in tiller at 48 hours were 1% of total radioactivity of $\^$14/C-G009 administered. The expired air, urinary and fecal excretion of radioactivity within 24hours after administration were 61.5%, 1.9% and 21.2% of total radioactivity of $\^$14/C-G009 administered. The biliary excretion of radioactivity in rat increased slightly for 0-6 hours after administration. The biliary excretion of radioactivity within 48hours were 1.97%.

• Transactions of the Korean hydrogen and new energy society
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• v.27 no.6
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• pp.693-701
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• 2016

Steam gasification of low rank coals is possible at relatively low temperature and low pressure, and thus shows higher efficiency compared to high rank coals. In this study, the gasification reactivity of four different Indonesian low rank coals (Samhwa, Eco, Roto, Kideco-L) was evaluated in $T=700-800^{\circ}C$. The low rank coals containing $53.8{\pm}3.4$ wt% volatile matter in proximate analysis and $71.6{\pm}1.2$ wt% carbon in ultimate analysis showed comparable gasification reactivity. In addition, $K_2CO_3$ catalyst rapidly accelerated the reaction rate at $700^{\circ}C$, and all of the coals were converted over 90% within 1 hour. The XRD analysis showed no significant difference in carbonization between the coals, and the FT-IR spectrum showed similar functional groups except for differences due to moisture and minerals. TGA results in pyrolysis ($N_2$) and $CO_2$ gasification atmosphere showed very similar behavior up to $800^{\circ}C$ regardless of the coal species, which is consistent with the steam gasification results. This confirms that the indirect evaluation of the reactivity can be made by the above instrumental analyses.

• BMB Reports
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• v.48 no.10
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• pp.571-576
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• 2015

SB743921 is a potent inhibitor of the spindle protein kinesin and is being investigated in ongoing clinical trials for the treatment of myeloma. However, little is known about the molecular events underlying the induction of cell death in multiple myeloma (MM) by SB743921, alone or in combination treatment. Here, we report that SB743921 induces mitochondria-mediated cell death via inhibition of the $NF-{\kappa}B$ signaling pathway, but does not cause cell cycle arrest in KMS20 MM cells. SB743921-mediated inhibition of the $NF-{\kappa}B$ pathway results in reduced expression of SOD2 and Mcl-1, leading to mitochondrial dysfunction. We also found that combination treatment with SB743921 and bortezomib induces death in bortezomib-resistant KMS20 cells. Altogether, these data suggest that treatment with SB743921 alone or in combination with bortezomib offers excellent translational potential and promises to be a novel MM therapy.