• Korean Journal of Agricultural Science
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• v.39 no.3
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• pp.427-439
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• 2012

In this study, an experiment with large-scale model was performed according to raising embankment in order to investigate the behaviour of failure due to overtopping. The pore water pressure, earth pressure and settlement by high water level, a rapid drawdown and overtopping were compared and analyzed. Also, seepage analysis and slope stability analysis were performed for steady state and transient conditions. The pore water pressure and earth pressure for inclined core type showed high value at the base of the core, but they showed no infiltration by leakage. The pore water pressure and earth pressure by overtopping increased at the upstream slope and core, it is considered a useful data that can accurately estimate the possibility of failure of the reservoir. The behavior of failure due to overtopping was gradually enlarged towards the downstream slope from reservoir crest, and the inclined core after the raising embankment was influenced significantly to prevent the reservoir failure. The pore water pressure distribution for steady state and transient condition showed positive (+) pore water pressure on the upstream slope, it was gradually changed negative (-) pore water pressure on the downstream slope. The pore water pressure by overtopping showed a larger than the high water level at the downstream slope, it was likely to be the piping phenomenon because the hydraulic gradients showed largely at the inclined core and reservoir crest. The safety factor showed high at the steady state, and transient conditions did not show differences depending on the rapid drawdown.

• Journal of Microbiology and Biotechnology
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• v.30 no.3
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• pp.427-438
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• 2020

Middle East respiratory syndrome coronavirus (MERS-CoV) infects the lower respiratory airway of humans, leading to severe acute respiratory failure. Unlike human dipeptidyl peptidase 4 (hDPP4), a receptor for MERS-CoV, mouse DPP4 (mDPP4) failed to support MERS-CoV infection. Consequently, diverse transgenic mouse models expressing hDPP4 have been developed using diverse methods, although some models show no mortality and/or only transient and mild-to-moderate clinical signs following MERS-CoV infection. Additionally, overexpressed hDPP4 is associated with neurological complications and breeding difficulties in some transgenic mice, resulting in impeding further studies. Here, we generated stable hDPP4-transgenic mice that were sufficiently susceptible to MERS-CoV infection. The transgenic mice showed weight loss, decreased pulmonary function, and increased mortality with minimal perturbation of overexpressed hDPP4 after MERS-CoV infection. In addition, we observed histopathological signs indicative of progressive pulmonary fibrosis, including thickened alveolar septa, infiltration of inflammatory monocytes, and macrophage polarization as well as elevated expression of profibrotic molecules and acute inflammatory response in the lung of MERS-CoV-infected hDPP4-transgenic mice. Collectively, we suggest that this hDPP4-transgenic mouse is useful in understanding the pathogenesis of MERS-CoV infection and for antiviral research and vaccine development against the virus.

• The Journal of Pediatrics of Korean Medicine
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• v.29 no.4
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• pp.97-107
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• 2015

Objectives Hataedock is the treatment that dispels toxic heat and meconium gathered at the fetus for the new born baby by orally administered herbal extracts. The purpose of this study was to evaluate whether Hataedock alleviate inflammatory skin damages in AD-induced NC/Nga mice through regulating of skin barrier maintain and Th2 differentiation. Methods We established an AD model in the 3-week-old NC/Nga mice through the repeated application of DNFB (dinitrochlorobenzene) on days 28, 35, 42 after Hataedock treatment which was orally administered. We identified the changes of skin barrier and Th2 differentiation through the histological and immunohistochemical changes of protein kinase C (PKC), interleukin (IL)-4, degranulated mast cell, Substance P and MMP-9. Results Our results suggested that Hataedock treatment significantly down-regulated levels of PKC by 82% (p < 0.001), as well as IL-4 by 56% (p < 0.001). Hataedock also suppressed mast cell infiltration, ear edema formation. and Substance P in the tissue of NC/Nga mice were decreased by 57% (p < 0.001), and MMP-9 by 55% (p < 0.001). Conclusions These results suggest that Hataedock alleviates AD through the down-regulation of PKC and Th2 cytokines, which are involved in the initial steps of AD development. Hataedock have potential application for the treatment of AD.

• Journal of Periodontal and Implant Science
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• v.45 no.2
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• pp.46-55
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• 2015

Purpose: This study evaluated the mechanical and structural properties of biphasic calcium phosphate (BCP) blocks processed using a modified extrusion method, and assessed their in vivo effectiveness using a rabbit calvarial defect model. Methods: BCP blocks with three distinct ratios of hydroxyapatite (HA):tricalcium phosphate (TCP) were produced using a modified extrusion method:HA8 (8%:92%), HA48 (48%:52%), and HA80 (80%:20%). The blocks were examined using scanning electron microscopy, X-ray diffractometry, and a universal test machine. Four circular defects 8 mm in diameter were made in 12 rabbits. One defect in each animal served as a control, and the other three defects received the BCP blocks. The rabbits were sacrificed at either two weeks (n=6) or eight weeks (n=6) postoperatively. Results: The pore size, porosity, and compressive strength of the three types of bone block were $140-170{\mu}m$, >70%, and 4-9 MPa, respectively. Histologic and histomorphometric observations revealed that the augmented space was well maintained, but limited bone formation was observed around the defect base and defect margins. No significant differences were found in the amount of new bone formation, graft material resorption, or bone infiltration among the three types of BCP block at either of the postoperative healing points. Conclusions: Block bone substitutes with three distinct compositions (i.e., HA:TCP ratios) processed by a modified extrusion method exhibited limited osteoconductive potency, but excellent space-maintaining capability. Further investigations are required to improve the processing method.

• Journal of Physiology & Pathology in Korean Medicine
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• v.24 no.5
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• pp.796-806
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• 2010

Atopic dermatitis induced NC/Nga mice were used to investigate the efficacy of BDH(Baedokhwan) on the recovery of dermatitic symptoms through its influence on the immune related factors and histological changes. First of all, BDH treated group showed improvement of atopic dermatitis with naked eye observation, and significant decrease of clinical index(CI) was observed after 14 weeks. And Infiltration of leukocytes was suppressed in BDH treated group, and the thickness of hypertrophied epidermis and dermis were decreased. In dorsal skin, BDH treated group showed significant decrease of the ratio of CD3+, CD11b+/Gr-1+ immune cells by 52.8%, 25.2, respectively. And also significant decrease the level of IL-5 mRNA and IL-13 mRNA by 44.4%, 28.0, respectively. In PBMC and serum, BDH treated group showed an decrease of CD4+/CD45+, B220+/CD23+, CD4+, CD8+, CD4+/CD25+ immune cells by 35.0%, 12.6%, 42.7%, 31.6% and 55.6%, respectively, and the level of histamine was decreased by 39.0%. The results above indicated that BDH clinically used for atopic dermatitis treatment has objective validity, and therefore can be provided as the basic data for anti-allergic and anti-inflammatory studies.

• International Journal of Highway Engineering
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• v.3 no.1 s.7
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• pp.165-176
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• 2001

Joints in jointed concrete Pavement are designed to control against randomly occurred cracks within slabs, which may be caused by temperature or moisture variation. The advantage of these artificial cracks (joints) over naturally occurred cracks are easy access of protections, such as installation of joint seal and load transfer mechanism. The potential benefits of joint seals are to prevent infiltration of surface water through the joint into underlying soil and intrusion of incompressible materials (debris, fine size aggregate) in to the joint, which may prevent weakening of underlying soils and spallings due to excessive compressive stress, respectively. For the adequate design of joint seal, horizontal variation of joint widths (horizontal joint movements) are essential inputs. Based on long-term in-situ joint movement data of sixteen jointed concrete pavement sections in Long Term Performance Pavement Seasonal Monitoring Program (LTPP SMP), it was indicated that considerable Portion of joints showed no horizontal movements with change in temperature. This Phenomenon is called 'Joint Freezing'. Possible cause for joint freezing is that designed penetrated cracks do not occur at a joint. In this study, a model for the prediction of the ratio of freezing joints in a particular pavement sections is proposed. In addition, possible effects of joint freezing against pavement performance are addressed.

• Biomolecules & Therapeutics
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• v.26 no.6
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• pp.576-583
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• 2018

Human rhinoviruses (HRV) are one of the major causes of common cold in humans and are also associated with acute asthma and bronchial illness. Heat-shock protein 90 (Hsp90), a molecular chaperone, is an important host factor for the replication of single-strand RNA viruses. In the current study, we examined the effect of the Hsp90 inhibitor pochonin D, in vitro and in vivo, using a murine model of human rhinovirus type 1B (HRV1B) infection. Our data suggested that Hsp90 inhibition significantly reduced the inflammatory cytokine production and lung damage caused by HRV1B infection. The viral titer was significantly lowered in HRV1B-infected lungs and in Hela cells upon treatment with pochonin D. Infiltration of innate immune cells including granulocytes and monocytes was also reduced in the bronchoalveolar lavage (BAL) by pochonin D treatment after HRV1B infection. Histological analysis of the lung and respiratory tract showed that pochonin D protected the mice from HRV1B infection. Collectively, our results suggest that the Hsp90 inhibitor, pochonin D, could be an attractive antiviral therapeutic for treating HRV infection.

• The Journal of Korean Medicine
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• v.20 no.2
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• pp.98-107
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• 1999

This study aimed to find out Oyo-Tang's effects on allergic asthma using the Egg-White Implant(EWI) method model recommended by Siqueira et al. Oyo-Tang has widely been prescribed and used in Oriental Medicine for controlling and curing of cough, nasal obstruction, pharyngeal pain and hoarseness. Previous studies have demonstrated that Oyo-Tang has analgesic, sedative, anticonvulsive, antitussive and antihistamine effects. But it was uncertain whether Oyo-Tang could inhibit the allergic reactions, to alleviate the symptoms of allergic asthma. With such aim. the respiratory patterns and eosinophil infiltration in the tracheal mucosa of rats with experimentally induced allergic asthma (using EWI method) were mainly observed. The results are as follows: 1. Oyo-Tang decreased the number of poor respiration with respect to control group (P<0.05) 2. Oyo-Tang decreased the number of eosinophils infiltrated in tracheal mucosa with respect control group (P<0.05). The above results demonstrate that Oyo-Tang has the inhibitory effects on the process allergic asthma and suggest that it could be used in relieving patients of the symptoms caused allergic asthma.

• Journal of Microbiology and Biotechnology
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• v.29 no.12
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• pp.1975-1981
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• 2019

Recently, outbreaks of food-borne diseases linked to fresh produce have been an emerging public health concern worldwide. Previous research has shown that when human pathogens co-exist with plant pathogens, they have improved growth and survival rates. In this study, we have assessed whether Escherichia coli O157:H7 benefits from the existence of a phytopathogenic bacterium and the underlying mechanisms were further investigated. When Pseudomonas syringae pv. tomato DC3000 (Pst DC3000) and E. coli O157:H7 were co-inoculated by either dipping or infiltration methods, the populations of E. coli O157:H7 increased; however, no effect was observed when type three secretion system (T3SS) mutants were used instead, suggesting that E. coli O157:H7 benefits from the presence of Pst DC3000. In addition, this study confirmed that the E. coli O157:H7 populations increased when they occupied the tomato leaf intercellular space; this colonization of the interior of the leaves was possible due to the suppression of the PAMP-triggered immunity (PTI) by Pst DC3000, in particular with the AvrPto effector. In conclusion, our data support a plausible model that E. coli O157:H7 benefits from the presence of Pst DC3000 via AvrPto suppression of the PTI resistance.

• Explosives and Blasting
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• v.34 no.4
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• pp.1-9
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• 2016

For underwater steel structure, cut that underwater shaped charge device that combines a spring hose, which is an external device of pressure resistance and flexibility with flexible shaped charge, was invented. As a basic experiment for an optimum condition design, an penetration performance was compared by external device shape. To evaluate the result of an experiment, image analysis was carried out after obtaining the model by using the liquid rubber for the penetrated steel plate. To simulate the penetrating process of shaped charge, the AUTODYN program has been used. As a result of analysis, while the average penetration depth of circular and square shaped external devices were similar, the penetration quality was more uniform in the case of circle. In addition, water infiltration occurred in square case, displacement and strain rate according to the increase of the water pressure were measured high.