• Korean Journal of Pharmacognosy
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• v.33 no.2 s.129
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• pp.130-136
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• 2002

Melanogenesis is a physiological process resulting in the synthesis of melanin pigments, which play a crucial protective role against skin photocarcinogenesis. The heart wood of Caesalpinia sappan L.(C. sappan) has long been commonly used in Oriental folk medicines to promote blood circulation, and as an emmenagogue, analgesic or anti-inflammatory agent as well as a remedy for thrombosis. From the heartwood, many constituents have been purified and among them, brazilin and hematoxylin are two of the most abundant. This present study was designed to investigate the inhibitory effect of butanol extract from C. sappan on proliferation and melanogenesis in Melan-a cells. After 48 h treatment of these cells with various concentrations of butanol extract, the cells showed a dose-dependent inhibition in their proliferation without apoptotic cell death. Therefore, the growth retardation by the extract may be due to the cell arrest or cell differentiation. We also estimated total melanin content as a final product and activity of tyrosinase, a key enzyme, of melanogenesis in Melan-a cells. The melanin content and tyrosinase activity were deσeased in extract-treated cells in a dose dependent manner compared to control group. The butanol extract also resulted in a decrease of melanin content in ${\alpha}-melanocyte-stimulating$ hormone (MSH)-induced melanogenesis, indicating that butanol extract of C. sappan could be developed as skin whitening components of cosmetics.

• Journal of Trauma and Injury
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• v.30 no.4
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• pp.173-178
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• 2017

Purpose: Most patients with acute low back pain visit emergency room (ER). They mostly need beds, and if their length of stay is longer, it can become difficult to accommodate new patients at the ER. We analyzed the treatment process of patients with back pain and tried to find method for shortening of the length of stay at the ER. Methods: We retrospectively analyzed the medical records of patients with back pain who visited at our ER for one year. Patients were divided into two groups according to their length of stay at ER and were compared the charateristcs of between two groups. Results: A total of 274 patients were included in the study. Eigthy-nine patients (32.5%) were in the group with less than 3 hours and 185 patients (67.5%) were in the other group. In the comparison of the two groups according to the medical departments, the number of patients who were in group with more than 3 hours were 25 (14.0%) in the emergency department, 94 (50.5%) in neurosurgery, 66 (35.5%) in orthopedic surgery. Length of stay was significantly increased in orthopedic surgery and neurosurgery (p=0.014). In addition, the length of stay was longer when computed tomography and magnetic resonance imaging examinations were performed (p=0.000). Regardless of the type of analgesic agent, the median time to the analgesic treatment was shorter in the group with less than 3 hours (p=0.034). Conclusions: In patients with back pain who visit the ER, the emergency medicine doctor will early control the pain and do not unnecessary image examination to reduce a length of stay at the ER.

• Journal of Korean Society of Water and Wastewater
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• v.18 no.3
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• pp.377-384
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• 2004

In the present study, a feasibility of an advanced oxidation process using UV/Hydrogen peroxide($H_2O_2$) system equipped with a medium pressure lamp for secondary effluent reclamation was investigated. Initial concentration of $H_2O_2$ and pH were changed to determine the optimum operation condition for the system. The removal efficiency of color was than 80% with 14.3mg/L of initial $H_2O_2$ and 5 minute of contact time in the UV/$H_2O_2$ system. The color removal was analyzed using first-order reaction equation. The dependence of rate constant (k) on initial $H_2O_2$ represented the rational relationship with maximum value. Residual $H_2O_2$ caused increase of effluent COD, since analyzing agent, dichromate, reacted with $H_2O_2$ in the sample. Therefore, excess initial concentration of $H_2O_2$ would significantly affect effluent COD measurement. At pH variation experiment, both residual $H_2O_2$ and color showed peak in the neutral pH range with the same pattern. Effect of $H_2O_2$ dose also enhanced color removal but raised residual $H_2O_2$ problem in the continuous operation UV system. In conclusion, these results indicated that medium pressure UV/$H_2O_2$ system could be used to control color in the secondary effluent for reclamation and reuse.

• Journal of Internet Computing and Services
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• v.9 no.2
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• pp.83-88
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• 2008

Session initiation protocol (SIP) is an application-layer prolocol to initiate and control multimedia client session. When client ask to use a SIP service, they need to be authenticated in order to get service from the server. Authentication in a SIP application is the process in which a client agent present credentials to another SIP element to establish a session or be granted access to the network service. In 2005, Yang et al. proposed a key exchange and authentication scheme for use in SIP applications, which is based on the Diffie-Hellman protocol. But, Yang et al.'s scheme is not suitable for the hardware-limited client and severs, since it requires the protocol participant to perform significant amount of computations (i.e., four modular exponentiations). Based on this observation. Huang and Wei have recently proposed a new efficient key exchange and authentication scheme thor improves on Yang et al.'s scheme. As for security, Huang and Wei claimed, among others, that their scheme is resistant to offline dictionary attacks. However, the claim turned out to be untrue. In this paper, we show thor Huang and Wei's key exchange and authentication scheme is vulnerable to on offline dictionary attack and forward secrecy.

• Journal of the Korean Association of Oral and Maxillofacial Surgeons
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• v.28 no.2
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• pp.147-154
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• 2002

Genistein that is a component of soy has been reported to have a protective effect on the carcinogenesis of various tumors and to inhibit the growth of a wide variety of tumor cell in vitro. Angiogenesis is an essential process for the carcinogenesis, growth, invasion and metastasis of cancer and genistein has been suggested to act as natural anti-angiogenic agent. The purpose of this study was to evaluate the effects of genistein on the vascular endothelial growth factor (VEGF) expression in hamster buccal pouch oral carcinogenesis model induced by 9, 10-dimethyl 1,2-benzanthracene (DMBA). Experimental group that were supplied with 0.1mg/day genistein were sacrificed by time schedules and routinely processed for immunohistochemical examination of VEGF. In genistein treated group, carcinogenesis was retarded with respect to the acanthosis, hyperkeratosis, and epithelial dysplasia. Immunohistochemical study showed that the VEGF protein of genistein group was less expressed than that of the control group. (p<0.05) Thus, it is postulated that genistein has chemopreventive effect on the oral carcinogenesis, and this chemopreventive effect, at least partly, is originated from the anti-angiogenic effect of genistein

• Journal of the Korean Ceramic Society
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• v.54 no.2
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• pp.108-113
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• 2017

The use of aluminum-based coagulants in water pretreatment is being carefully considered because aluminum exposure is a risk factor for the onset of Alzheimer's disease. Lightly burned-dolomite kiln dust (LB-DKD) was evaluated as an alternative coagulant because it contains high levels of the healthful minerals calcium and magnesium. An organic pore forming agent (OPFA) was incorporated to prepare porous granules after OPFA removal through a thermal decomposition process. A spray drying method was used to produce uniform and reproducible spherical granules with low density, since fine dolomite particles have irregular agglomeration behavior in the hydration reaction. The use of fine dolomite powder and different porosity granules led to a visible color change in raw algae (RA) containing water, from dark green to transparent colorlessness. Also, dolomite powders and granules exhibited a mean removal efficiency of 48.3% in total nitrogen (T-N), a gradual increase in the removal efficiency of total phosphorus (T-P) as granule porosity increased. We demonstrate that porous dolomite granules can improve the settling time and water quality in summer seasons for the emergent treatment of excessive algal blooms in eutrophic water.

• Korean Journal of Plant Resources
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• v.24 no.2
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• pp.181-188
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• 2011

This study was carried out to estimate beneficial effects of Foeniculi fructus water extract on activities of key enzymes such as lipoprotein lipase (LPL), acyl-CoA synthetase (ACS), and hormone sensitive lipase (HSL) on lipid metabolism related with obesity. LPL and ACS were extracted from the epididymal adipose tissue and liver of C57BL/6J normal and obese mouse. Foeniculi fructus water extract treatment significantly reduced the activity of normal and obese LPL. When 100 ppm of Foeniculi fructus water extracts were tested, they decreased obese LPL activity by 12.0%. Foeniculi fructus water extract activated obese ACS activity by 7-fold compared with control at 1,000 ppm concentration. Expression of HSL mRNA was increased in Foeniculi fructus water extracts treated cells compared with non treated cells. All things considered, Foeniculi fructus water extract efficiently inhibits the influx of fatty acid into the cell, and activates metabolic process that uses fatty acids flowing as an energy source. Thus, it suggest that Foeniculi fructus water extract may have great potential as a novel anti-obesity agent.

• Journal of Microbiology and Biotechnology
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• v.20 no.5
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• pp.935-941
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• 2010

The emergence of antibiotic-resistant bacterial strains is one of the most critical problems of modern medicine. Bacteriophages have been suggested as an alternative therapeutic agent for such bacterial infections. In the present study, we examined the therapeutic potential of phage Kpn5 in the treatment of Klebsiella pneumoniae B5055-induced burn wound infection in a mouse model. An experimental model of contact burn wound infection was established in mice employing K. pneumoniae B5055 to assess the efficacy of phage Kpn5 in vivo. Survival and stability of phage Kpn5 were evaluated in mice and the maximum phage count in various organs was obtained at 6 h and persisted until 36 h. The Kpn5 phage was found to be effective in the treatment of Klebsiella-induced burn wound infection in mice when phage was administered immediately after bacterial challange. Even when treatment was delayed up to 18 h post infection, when all animals were moribund, approximately 26.66% of the mice could be rescued by a single injection of this phage preparation. The ability of this phage to protect bacteremic mice was demonstrated to be due to the functional capabilities of the phage and not due to a nonspecific immune effect. The levels of pro-inflammatory cytokines (IL-$1{\beta}$ and TNF-${\alpha}$) and anti-inflammatory cytokines (IL-10) were significantly lower in sera and lungs of phage-treated mice than phage untreated control mice. The results of the present study bring out the potential of bacteriophage therapy as an alternate preventive approach to treat K. pneumoniae B5055-induced burn wound infections. This approach not only helps in the clearance of bacteria from the host but also protects against the ensuing inflammatory damage due to the exaggerated response seen in any infectious process.

• Journal of Adhesion and Interface
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• v.20 no.4
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• pp.146-154
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• 2019

In this study, alkoxysilane-functionalized amphiphilic polymer (AFAP), which have hydrophilic segment and hydrophobic segment functionalized by alkoxysilane group at the same backbone, was synthesized and used as a dispersant and control agent for reaction rate in the preparation of colloidally stable organic-inorganic (O-I) hybrid sols. After reaction with fluorosilane compounds, fluorinated O-I hybrid sols were prepared and coated onto glass substrate to form hydrophobic O-I hybrid coating films through low-temperature curing process. Surface hardness and hydrophobicity of cured coating films were varied with type of solvent and composition of AFAP and fluorinated alkoxysilane compounds. At appropriate solvent and composition of fluorinated alkoxysilane compounds, O-I hybrid coating film having high transparency and surface hardness could be prepared, which could be applicable to cover window of solar cell and displays.

• The Journal of Korean Association of Computer Education
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• v.3 no.1
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• pp.127-134
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• 2000

Distance education, which emerged under the influence of both the rapid development of hi-tech information technology and the constructivism theory of learning, enables learners to acquire knowledge and skills needed by monitoring their learning process for themselves. Emphasis on web-based distance education and contructivism as a basis of learner-centered education does not mean that those education systems are performed without teachers or in noninterference. This study proposes a model of distance education system in which learners are taught in various levels of learning with the help of teacher agents. In the model teacher agents produce the learners' respective learning model considering the information on individual learners and also control the progress to the next step of learning with the result of the evaluation of learning accomplishment. The model of distance education system suggested in this study is able to help solve the problem that the learning resources web-based distance education provides were used only as objects of web search and to supply a basis of realizing learner-centered education.