• Journal of Chest Surgery
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• v.42 no.6
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• pp.685-695
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• 2009

Background: Calcification is the most frequent cause of clinical failure of bioprosthetic tissues that are fabricated from Glutaraldehyde (GA)-fixed porcine valve or bovine pericardium. We recently used a multi-factorial approach of employing different mechanisms to investigate how to reduce the calcification of bioprosthetic tissues. The purpose of the present study was to evaluate the synchronized synergism using ethanol, L-lysine and $NaBH_4$ in glutaraldehyde treated porcine pericardium from the standpoint of calcification and tissue elasticity. Material and Method: Porcine pericardium was fixed with 0.625% GA (commercial fixation). An interim step of ethanol (80%; 1 day at room temperature) or L-lysine (0.1 M; 2 days at $37^{\circ}C$) or $NaBH_4$ (0.1 M; 2 days at room temperature) was followed by completion of the GA fixation (2 days at $4^{\circ}C$ and 7 days at room temperature). The tensile strength and thickness of the samples were measured. The treated pericardiums were implanted subcutaneously into three-week old Sprague-Dawley rats for 8 weeks. The calcium content was assessed by atomic absorption spectroscopy and the histology of the samples. Result: The amount of calcium in the pericardium pretreated with ethanol (13.6${\pm}$10.0 ug/mg, p=0.008), L-lysine (15.3${\pm}$1.0 ug/mg, p=0.002) and both (16.1${\pm}$11.1 ug/mg, p=0.012) was significantly reduced compared with the control (51.2${\pm}$8.5 ug/mg). However, $NaBH_4$ pretreatment (65.7${\pm}$61.8 ug/mg, p=0.653) and combined pretreatment that including ethanol, L-lysine and $NaBH_4$ (92.9${\pm}$58.3 ug/mg, p=0.288) were not significantly different from the controls(51.2${\pm}$8.5 ug/mg). Both the combined pretreatment using ethanol and L-lysine (7.60${\pm}$1.55, p=0.76) and the combined pretreatment that included ethanol, L-lysine and $NaBH_4$ (7.47${\pm}$1.85, p=0.33) increased the tensile strength/thickness ratio compared with that of the controls (4.75${\pm}$1.88). Conclusion: The combined pretreatment using ethanol and L-lysine seemed to decrease the calcification of porcine pericardium fixed with glutaraldehyde, as compared to single pretreatment, and it increase the tissue elasticity, but to the degree that showed synchronized synergism. $NaBH_4$ pretreatment seemed to increase the calcification of porcine pericardium, irrespective of whether single or combined pretreatment was used.

• Proceedings of the Materials Research Society of Korea Conference
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• 2007.11a
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• pp.33.2-33.2
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• 2007

• Journal of the Korean Society for Aeronautical & Space Sciences
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• v.43 no.4
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• pp.296-303
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• 2015

The concentration of solute in a $NaBH_4$ solution is limited due to the low solubility of $NaBO_2$. The performance of a hydrogen generation system was evaluated using various concentrations of $NaBH_4$ solution. First, a self-hydrolysis test and a hydrogen generation test for 30 min were performed. The composition of $NaBH_4$ solution was selected to be 1 wt% NaOH + 25 wt% $NaBH_4$+74wt% $H_2O$ by considering the amount of hydrogen loss, stability of hydrogen generation, $NaBO_2$ precipitation, conversion efficiency, and the purpose of its application. A hydrogen generation system for a 200 W fuel cell was evaluated for 3 h. Although hydrogen generation rate decreased with time due to $NaBO_2$ precipitation, hydrogen was produced for 3 h (conversion efficiency: 87.4%). The energy density of the 200 W fuel cell system was 263 Wh/kg. A small unmanned aerial vehicle with this fuel cell system can achieve 1.5 times longer flight time than one flying on batteries.

• Transactions of the Korean hydrogen and new energy society
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• v.25 no.5
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• pp.475-481
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• 2014

Ammonia borane ($NH_3BH_3$), as a source material for energy generation and hydrogen storage, has attracted growing interest due to its high hydrogen content. We have investigated the synthesis of ammonia borane from sodium borohydride ($NaBH_4$) and ammonium chloride ($NH_4Cl$) utilizing a low-temperature process. From our results, we obtained a maximum synthetic yield of 98.2% of ammonia borane complex. The diammoniate diborane (DADB) was detected in about 5~10mol% with in the solid ammonia borane by solid-state $^{11}B$-NMR analysis. The synthesized solid ammonia borane products were studied to characterize hydrogen release upon thermal dehydrogenation.

• Journal of the Korean Society for Geothermal and Hydrothermal Energy
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• v.4 no.1
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• pp.1-10
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• 2008

A magnetotelluric survey and geological survey have been performed to delineate deeply extended fracture systems at the geothermal field in Seokmo Island, Inchon, Korea. One borehole(BH-1) succeed to meet a large fracture system at the depth of 750 m where approximately $72^{\circ}C$ geothermal water is overflowing, while the other borehole(BH-2), which is about 200 m eastward from BH-1, failed to develop enough geothermal water even at the depth of 1,200m. Though there have been so many electric noise sources around the survey region, good quality of MT data above 1 Hz could be obtained with careful installation, remote reference processing. Inversion of MT data for two lines roughly perpendicular to the two major lineaments respectively show that the two lineaments are related to the fracture systems that are extended at least down to 1.5 km depth and inclined eastwards. From the interpretation, additional drilling for BH-2 is recommended and finally meet the fracture systems at the depth of 1,280 m and resulted in overflow of large amount of geothermal water of temperature $69.4^{\circ}C$ from BH-2.

• The Bulletin of The Korean Astronomical Society
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• v.37 no.1
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• pp.46.2-46.2
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• 2012

The black hole mass-stellar velocity dispersion ($M_{BH}-{\sigma}_*$) relation observed in the present-day universe has motivated numerous studies on the black hole-galaxy co-evolution. It is crucial to define the$M_{BH}-{\sigma}_*$ local active galaxies since cosmic evolution of the correlations is calibrated based on the local relation. However, stellar velocity dispersion is difficult to measure in active galaxies due to much higher AGN continuum than stellar pseudo-continuum, resulting in a small sample with reliable velocity dispersion measurements for studying the AGN $M_{BH}-{\sigma}_*$ relation. To increase the sample size and improve the measurements, we obtained high S/N near-IR spectra for 3 local AGNs, i.e., NGC 3227, Akn 120, 3C 390.3, for which reverberation black hole masses are measured, using the TripleSpec at the Palomar 5-m Telescope. By investigating aperture effect and correcting for rotation component, we determine the luminosity-weighted ${\sigma}_*$, based on the spatially resolved kinematics and compare them with optical measurements from literature. Combining our new measurements with literature data, we present an improved $M_{BH}-{\sigma}_*$ relation for the enlarged sample of reverberation-mapped AGNs.

• The Bulletin of The Korean Astronomical Society
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• v.35 no.1
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• pp.80-80
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• 2010

About 50% of Active Galactic Nuclei(AGNs) are found to be red and dust-obscured. They are believed to be in an early dusty stage of AGNs evolution or affected by dust torus in the direction of line of sight. However, optical spectrum is affected by dust extinction, making it difficult to study their properties, such as FWHM and luminosity. In order to reveal the mass of central Black Hole(BH) in red AGN, we establish a new BH mass estimator for typical type1 AGNs using Near InfraRed(NIR) hydrogen line($P_{\alpha}$ and $P_{\beta}$), since these lines are at longer wavelength, less affected by dust extinction than optical hydrogen lines, such as $H_{\alpha}$ and $H_{\alpha}$. To derive the new empirical formula, we use a sample of well-known 36 AGN with a wide BH mass range of $10^6-10^9\;M_{\odot}$, where $M_{BH}s$ are estimated by reverberation mapping method and single epoch method. The $P_{\alpha}/P_{\beta}$ luminosities and FWHMs are derived by analyzing IRTF NIR spectra or taken from literature values. We show that luminosities and FWHMs of these lines correlate well with those of Balmer lines. Suggesting that Paschen and Balmer broad lines are originated from same region. Finally, we present the new $M_{BH}$ formula that are based on $P_{\alpha}/P_{\beta}$ luminosity and FWHM. We hope that our result will be used for investigating red AGNs.

• Journal of Microbiology and Biotechnology
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• v.22 no.5
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• pp.600-606
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• 2012

Studies into the cell death program termed apoptosis have resulted in new information regarding how cells control and execute their own demise, including insights into the mechanism by which death-preventing factors can inhibit Bax-induced caspase activation. We investigated high temperature stress-induced cell death in Brassica rapa. Using a yeast functional screening from a Brassica rapa cDNA library, the BH5-127 EST clone encoding an apoptotic suppressor peptide was identified. However, a phylogenic tree showed that BH5-127 clusters within a clade containing SUMO-1 (Small Ubiquitin-like Modifier-1). BH5-127 was confirmed similar to have function to SUMO-1 as Fas suppression. Expression of BH5-127 showed that substantial suppression of cell death survived on SD-galactose-$Leu^-$-$Ura^-$ medium. The results suggest that BrSE ($\underline{B}$rassica rapa $\underline{S}$entrin $\underline{E}$ST, BH5-127) is one of the important regulatory proteins in programming cell death, especially in the seedling stage of Chinese cabbage.

• Journal of Korean Medicine for Obesity Research
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• v.12 no.1
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• pp.48-58
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• 2012

Objectives These prescribing recommendations have been written to guide clinicians on the appropriate use of Bangpungtongseong-san(BT) and Bangkihwangki-tang(BH) in the treatment of obesity. These recommendation are aimed at providing evidence based information concerning diagnosis and management of obesity. Methods We collected all relevant references about treatment effect of BT and BH on obesity in the forms of meta-analysis, systematic review, randomized controlled trial, case-control study, observational study and practice guideline from international and domestic databases and paper journals. We examined treatment effect, side effects, recommendations for dose, indication and contraindication of BT and BH. Results The treatment effect of BT and BH on obesity has been proved through clinical trial. BT is indicated for obese patients (Body mass index, $BMI{\geq}25$) with strong abdomen and a tendency to constipation, BH is indicated for obese patients ($BMI{\geq}25$) with a fair skinned, soft muscled, edematous and sweat easily. Conclusion We wish the information contained in theses recommendations will help clinicians reach a reasonable and beneficial decision with evidence-based results. Further studies are strongly needed to develop better treatment strategies for herbal medicines on obesity.

• Advances in pediatric surgery
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• v.16 no.2
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• pp.143-153
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• 2010

Congenital diaphragmatic disease is one of the common major congenital anomalies, and its mortality remained still high despite recent medical advances. The aim of this study is to examine the clinical characteristics of congenital diaphragmatic diseases. A total of 39 patients with congenital diaphragmatic disease that underwent surgery from January, 1997 to December, 2009 at Pusan National University Hospital were included in this study. Medical records were retrospectively reviewed. The male to female ratio was 30:9. Six out of 39 cases died (NS) before surgery, 17 patients had Bochdalek's hernia (BH), 11 patients hiatus hernia (HH), 4 diaphragmatic eventration (DE), and 1 Morgagni hernia (MH). There were no differences in mean birth weight and mean gestational age. NS (83.3 %). BH (35.3 %) was diagnosed more frequently than other diseases in the prenatal period. Three patients (17.6 %) of BH expired due to pulmonary hypoplasia and 1 patient had co-existing congenital heart disease. BH was diagnosed more frequently in the prenatal stage and had a higher motality rate than other conditions. Therefore, BH needs to be concentrated more than other anomalies.