• The Korea Journal of Herbology
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• v.32 no.1
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• pp.25-31
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• 2017

Objectives : Mori Radicis Cortex (MRC), the root epidermis of Morus alba L., has been traditionally used to treat lung-related diseases in Korean Medicine. The common of MRC is Mulberry bark Morus bark, and it's pharmaceutical properties and taste are known as sweet and cold, and it promotes urination and reduce edema by reducing heat from the lungs and soothe asthma. In the present study, anti-apoptotic mechanism of MRC in middle cerebral artery occlusion (MCAO) model in mice. Methods : Two-hundred grams of MRC was extracted with methanol at room temperature for 5 days, and this was repeated one time. After filtration, the methanol was removed using vacuum evaporator, then stored at $-20^{\circ}C$ until use. C57BL/6 male mice were housed in an environment with controlled humidity, temperature, and light cycle. In order to determine beneficial effects of MRC on ischemia induced brain damage, infarct volume, neurological deficit scores, activities of several apoptosis-related proteins such as caspase-8, -9, Bcl-xL in MCAO-induced brains of mice were analyzed. Mice in MRC-treated groups were orally administered 30, 100, or 300 mg/kg of body weight for three consecutive days before commencing the MCAO procedure. Results : Pre-treatment of MRC significantly reduced infarct volume in MCAO subjected mice applied with 300 mg/kg of MRC methanol extract, and MRC effectively inhibited Bcl-xL reduction and caspase-9 activation caused by MCAO-induced brain damage. Conclusions : MRC showed neuro-protective effects by regulating apoptosis-related protein signals, and it can be a potential candidate for the therapy of ischemia-induced brain damage.

• Imaging Science in Dentistry
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• v.33 no.2
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• pp.97-105
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• 2003

Purpose : To evaluate the effect of all-trans-retinoic acid (ATRA) on the radiosensitivity of normal human oral keratinocyte (NHOK). Materials and methods: Relative cell survival fraction including SF2 (survival fraction at 2 Gy) was calculated on the basis of colony formation assay. Data were fitted to the linear-quadratic model to establish the survival curve and calculate α and β values. Using flow cytometry at 1, 2, 3, 4, and 5 days after exposure to 2 and 10 Gy irradiation, cell cycle arrest and apoptosis were analysed. To understand the molecular mechanism of the radiosensitization of ATRA on NHOK, proteins related with apoptosis and cell cycle arrest were investigated by Western blot analysis. Results: Treatment with ATRA resulted in a significant decrease of SF2 value for NHOK from 0.63 to 0.27, and increased α and β value, indicating that ATRA increased radiosensitivity of NHOK. ATRA increased LDH significantly, but increasing irradiation dose decreased LDH, suggesting that the radiosensitizing effect of ATRA is not directly related with increasing cell necrosis by ATRA. ATRA did not induce appotosis but increased G2 arrest after 10 Gy irradiation, implying that the increased radiosensitivity of NHOK may be due to a decrease in mitosis casued by increasing G2 arrest. ATRA inhibited the reduction of p53 at 3 days after l0Gy irradiation and increased p21 at 1 day after 10 Gy irradiation. Further study is required to determine the precise relationship between this effect and the radiosensitizing effect of A TRA. Conclusion: These results suggested that ATRA increase radiosensitivity by inhibiting mitosis caused by increasing G2 arrest.

• Journal of the Korean GEO-environmental Society
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• v.15 no.6
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• pp.67-73
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• 2014

Landslide disasters including debris flows are the one of the most frequent natural disasters in Korea, and losses of lives and property damages due to these catastrophic events have been increased every year. Various mitigation programs and related policies have been conducted in order to respond and prepare landslide disasters. Most landslide reduction programs are, however, focused on recovery actions after the disasters and lead to unrealistic consequences to the affected people and their properties. The main objective of this study, therefore, is to evaluate the landslide hazard based on the identification of geomorphological features, which is for the preparedness of the landslide disasters. Two methodologies, SINMAP and vector dispersion analyses are used to simulate those characteristics where landslides are actually located. Results showed that both methods well discriminate geomorphic features between stable and unstable domains. This proves that geomorphological characteristics well describe a relationship with the existing landslide hazard. SINMAP analysis which is based on the consecutive model considering external factors like infiltration is well identify the landslide hazard especially for debris flow type landslides rather than vector dispersion focusing on a specific area. Combining with other methods focusing specific characteristics of geomorphological feature, accurate landslide hazard assessments are implemented.

• Journal of the Korean Society of Safety
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• v.25 no.6
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• pp.34-39
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• 2010

The purpose of this study is to suggest objective evaluation model as a plan to utilize as opportunity in establishing judgment standard of mutual inspection criteria and to upgrade inspection ability by reviewing and analyzing level of danger and importance in advance based on inspection results of inspection institutions regarding tower cranes used in construction fields. Tower crane is a mechanical device transporting construction supplies and heavy materials to places over 20~150M high from the ground for the period ranging from a short time of 2~3 months to two years after being installed in construction sites in vicinity of buildings or structures and is an important facility indispensable for construction sites. However, since use period after installation is short and professional technical ability of technicians working on-site about of tower crane is poor, systematic and quantitative safety management is not carried out As a part of researches on procedure of RBI(Risk Based Inspection) possible to apply to Knowledge Based System based on knowledge and experiences of experts as well as to tower cranes for solving these problems, quantitative RPN(Risk Priority Number) was applied to RPN utilizing technique of FMEA(Failure Mode and Effect Analyses). When general RBI 80/20 Rule was applied parts with high level of risks were found out as wire rope, hoist up/down safety device, reduction gear, and etc. However, since there are still many insufficient parts as risk analyses of tower crane were not established, it is necessary for experts with sufficient experiences and knowledge to supplement active RBI techniques and continuous researches on tower cranes by sharing and setting up data base of important information with this study as a starting point.

• Korean Journal of Construction Engineering and Management
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• v.13 no.5
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• pp.25-34
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• 2012

It has been five years since the Post-Construction Sale System of Housing was introduced. The purpose of this study is to identify objectives and effects of the Post-Construction Sale System of Housing and analyze change of profitability at different sales time from a supplier's point of view. Apartment buildings construction projects performed in Seoul are used for the case study. The present value of sales revenues, sensitivity and the present value of expected sales prices are analyzed. According to the findings, first, profits made from a Pre-construction sales system was 5.1%~6.2% higher than those from a Post-construction sales system. Among four plans of a Pre-construction sales system (A, B, C and D plan), sales revenue from the A plan, which takes a deposit at the time of starting construction, was the greatest. Second, increase of the rate of discount and decrease of sales revenues are in direct proportion. The bigger rate of discount leads actual reduction of sales revenues. Third, for the present value of sales revenues reflecting change in basic model construction cost, a Pre-construction sales system showed a little higher than that of a Post-construction sales system by approximately 2%. It should be known that this study suggests profitability of Pre-and Post-construction sales system by clearly measuring them in the supplier's point of view and calculates sales revenues, considering change of a sale price following change of sales time.

• Clean Technology
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• v.21 no.1
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• pp.22-32
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• 2015

In this study, we studied the characteristics of ion exchange for treatment of HSS (heat stable salts) which cause performance reduction in CO₂ gas capture amine solution using anion exchange resins. The optimum HSS removal efficiency, 96.1% was obtained when using strong base anion exchange resin SAR10 at dosage 0.05 g/mL, 316 K, pH 12 and the best resin regeneration efficiency, 78.8% was obtained using NaOH solution of 3 M at 316 K. The adsorption data were described well by the Freundlich model and the sorption intensity(n) was 2.0951 lying within the range of favorable adsorption. The adsorption selectivity coefficients were increased by increasing valences and size of ion and desorption selectivity coefficients showed a contradictory tendency to adsorption selectivity coefficients. By continuous HSS removal experiments, 13.3 BV of HSS contaminated solution was effectively treated and the optimum NaOH solution consumption was 5.2 BV to regenerate resins.

• Journal of the Earthquake Engineering Society of Korea
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• v.8 no.3
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• pp.63-76
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• 2004

This paper presents LRB-based hybrid base isolation systems employing additional active/semiactive control devices for mitigating earthquake-induced vibration of a cable-stayed 29 bridge. Hybrid base isolation systems could improve the control performance compared with the passive type-base isolation system such as LRB-installed bridge system due to multiple control devices are operating. In this paper, the additional response reduction by the two typical additional control devices, such as active type hydraulic actuators controlled by LQG algorithm and semiactive-type magnetorheological dampers controlled by clipped-optimal algorithm, have been evaluated bypreliminarily investigating the slightly modified version of the ASCE phase I benchmark cable-stayed bridge problem (i.e., the installation of LRBs to the nominal cable-stayed bridge model of the problem). It shows from the numerical simulation results that all the LRB based hybrid seismic isolation systems considered are quite effective to mitigate the structural responses. In addition, the numerical results demonstrate that the LRB based hybrid seismic isolation systems employing MR dampers have the robustness to some degree of the stiffness uncertainty of in the structure, whereas the hybrid system employing hydraulic actuators does not. Therefore, the feasibility of the hybrid base isolation systems employing semiactive additional control devices could be more appropriate in realfor full-scale civil infrastructure applications is clearly verified due to their efficacy and robustness.

• Journal of Advanced Marine Engineering and Technology
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• v.37 no.5
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• pp.500-509
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• 2013

This study reports a numerical analysis of the internal flow characteristics of the integrated urea-SCR muffler system with the various geometries of the multi-perforated tube which is set up between the muffler inlet and in front of SCR catalysts. The multi-perforated tube is generally used to disperse uniformly the urea-water solution spray and to make better use of the SCR catalyst, resulting in the increased $NO_x$ reduction and decreased ammonia slip. The effects of the multi-perforated tube orifice area ratios on the velocity distributions in front of the SCR catalyst, which is ultimately quantified as the uniformity index, were investigated for the optimal muffler system design. The steady flow model was applied by using a general-purpose commercial software package. The air at the room temperature was used as a working fluid, instead of the exhaust gas and urea-water solution spray mixture. From the analysis results, it was clarified that the multi-perforated tube geometry sensitively affected to the formation of the bulk swirling motion inside the plenum chamber set in front of the SCR catalyst and to the uniformity index of the velocity distribution produced at the inlet of the catalyst.

• Food Science and Preservation
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• v.15 no.3
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• pp.332-339
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• 2008

This study was performed to investigate the sorption characteristics and shelf-life of coated ascorbic acid Stability of ascorbic acid, which oxidizes easily during storage and processing, was achieved by applying a fluidized bed coating using Zein-DP and HPMC-FCC as covering materials. The monolayer moisture content calculated using the GAB equation showed a higher level of significance than when calculated using the BET equation. The fit to the isotherm curve was in the order of Halsey, Caurie, Oswin and Khun. The equilibrium relative humidity prediction model was established in terms of time and water activity, it had higher significance. The stability of the coated ascoribic acid during storage was investigated in terms of radical-scavenging activity, which decreased with increasing time of storage and was more affected at higher storage temperatures. The quality reduction rate constant (k) was calculated by a first-order reaction rate. The reaction rate constant increased with increasing storage temperature. The shelf-life of Zein-DP-coated ascorbic acid was estimated to be 45.83 days at 20C and 63.19 days at 10C, and the shelf-life for HPMC-FCC-coated ascorbic acid was estimated to be 28.84 days at 20C and 36.14 days at 10, the ascorbic acid was 24.52 days at $20^{\circ}C$ and 27.22 days at $10^{\circ}C$, respectively. Therefore, the fluidized bed coating effectively increased the stability of ascorbic acid.

• International Journal of Oral Biology
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• v.39 no.2
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• pp.97-105
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• 2014

The aim of this study was to determine the beneficial effect of propofol on human keratinocytes that have undergone hypoxia reoxygenation (H/R) injury and to investigate whether autophagy is associated with the protective mechanism. Thus, we evaluated how propofol influences the intracellular autophagy and apoptosis during the H/R process in the HaCaT cells. The cultured human keratinocyte cells were exposed to 24 h of hypoxia (5% $CO_2$, 1% $O_2$, 94% $N_2$) followed by 12 h of reoxygenation (5% $CO_2$, 21% $O_2$, 74% $N_2$). The experiment was divided into 4 groups: (1) Control=Normoxia ; (2) H/R=Hypoxia Reoxygenation ; (3) PPC+H/R=Propofol Preconditioning+Hypoxia Reoxygenation; (4) 3-MA+PPC+ H/R=3-MA-Methyladenine+Propofol Preconditioning+ Hypoxia Reoxygenation. In addition, Western blot analysis was performed to identify the expression of apoptotic pathway parameters, including Bcl-2, Bax, and caspase 3 involved in mitochondrial-dependent pathway. Autophagy was determined by fluorescence microscopy, MDC staining, AO staining, and western blot. The H/R produced dramatic injuries in keratinocyte cells. In our study, the viability of Propofol in H/R induced HaCaT cells was first studied by MTT assay. The treatment with 25, 50, and $100{\mu}M$ Propofol in H/R induced HaCaT cells enhanced cell viability in a dose-dependent manner and $100{\mu}M$ was the most effective dose. The Atg5, Becline-1, LC3-II, and p62 were elevated in PPC group cells, but H/R-induced group showed significant reduction in HaCaT cells. The Atg5 were increased when autophagy was induced by Propofol, and they were decreased when autophagy was suppressed by 3-MA. These data provided evidence that propofol preconditioning induced autophagy and reduced apoptotic cell death in an H/R model of HaCaT cells, which was in agreement with autophagy playing a very important role in cell protection.