• Journal of Korean Society on Water Environment
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• v.26 no.1
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• pp.61-70
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• 2010

The increase of impervious cover (IC) in a watershed is known as an important factor causing alteration of water cycle, deterioration of water quality and biological communities of urban streams. The study objective was to assess the impact of IC changes on the surface runoff characteristics of Kap Stream basin located in Geum river basin (Korea) using the Storm Water Management Model (SWMM). SWMM was calibrated and verified using the flow data observed at outlet of the watershed with 8 days interval in 2007 and 2008. According to the analysis of Landsat satellite imagery data every 5 years from 1975 to 2000, the IC of the watershed has linearly increased from 4.9% to 10.5% during last 25 years. The validated model was applied to simulate the runoff flow rates from the watershed with different IC rates every five years using the climate forcing data of 2007 and 2008. The simulation results indicated that the increase of IC area in the watershed has resulted in the increase of peak runoff and reduction of travel time during flood events. The flood flow ($Q_{95}$) and normal flow ($Q_{180}$) rates of Kap Stream increased with the IC rate. However, the low flow ($Q_{275}$) and drought flow ($Q_{355}$) rates showed no significant difference. Thus the subsurface flow simulation algorithm of the model needs to be revisited for better assessment of the impact of impervious cover on the long-term runoff process.

• Journal of the Korea institute for structural maintenance and inspection
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• v.11 no.6
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• pp.143-151
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• 2007

This study presents the experimental results of frost durability including resistance to freezing-thawing and surface scaling of concrete. Mixing design was proportioned with the various water-binder ratio between 0.37 and 0.47 and three different binder compositions corresponding to Type I cement without any supplementary cementitious materials(OPC), Type II cement with 50% blast-furnace slag replacement(BFS50), and ternary cement with Type III cement, 15% fly ash, and 35% slag replacement (BFS35%+FA15%). Test results showed that the mixing design with BFS50% and BFS35%+FA15% exhibited higher durability factor than that made with OPC only. Finally, the use of blend cement containing slag can be used effectively in terms of frost durability of the concrete exposed to severe condition under coastal environment like as flying salt, sea water spray, etc.

• Journal of the Korea institute for structural maintenance and inspection
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• v.14 no.6
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• pp.117-123
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• 2010

If FRP materials that have been known as high durability materials are exposed to harmful environmental factors, deterioration and characteristics of materials can be reduced due to chemical reaction such as hydrolysis. Therefore, to use FRP materials as building major materials, it is important to exactly grasp dynamic properties by use condition. Accordingly, this study stored FRP materials in a strong acid and alkali compound solution for a certain period to conduct simulation for acute or chronic, extreme changes by chemicals, and conducted a test for compressive, tensile, shear and bending strength to analyze changes in strength by kinds and storage days of chemicals. In conclusion, the study findings indicate excellent chemical resistance of FRP materials.

• Fire Science and Engineering
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• v.24 no.2
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• pp.97-105
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• 2010

The smoke control systems using pressure differentials are already well known as the most reliable method to prevent the smoke infiltration into the emergency stairs or safe spaces. However, it is true that many problems are domestically pointed out due to the insufficient understanding and technology on the smoke control systems using pressure differentials. In this regard, this work analyzed the effect of major factors for smoke control system using pressure differentials such as a duct area, opening area of air supply damper, improvement on open vestibules, stack effect and location of air supply. In conclusion, adequate pressure differentials can not be maintained in small duct because the smaller duct area have the large friction loss. Especially, It is confirmed that the major factor for deterioration of smoke control system performance is stack effect that makes pressure differentials smaller in the lower floors.

• Molecules and Cells
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• v.43 no.6
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• pp.581-589
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• 2020

Neurons have multiple dendrites and single axon. This neuronal polarity is gradually established during early processes of neuronal differentiation: generation of multiple neurites (stages 1-2); differentiation (stage 3) and maturation (stages 4-5) of an axon and dendrites. In this study, we demonstrated that the neuron-specific n-glycosylated protein NELL2 is important for neuronal polarization and axon growth using cultured rat embryonic hippocampal neurons. Endogenous NELL2 expression was gradually increased in parallel with the progression of developmental stages of hippocampal neurons, and overexpression of NELL2 stimulated neuronal polarization and axon growth. In line with these results, knockdown of NELL2 expression resulted in deterioration of neuronal development, including inhibition of neuronal development progression, decreased axon growth and increased axon branching. Inhibitor against extracellular signal-regulated kinase (ERK) dramatically inhibited NELL2-induced progression of neuronal development and axon growth. These results suggest that NELL2 is an important regulator for the morphological development for neuronal polarization and axon growth.

• PNF and Movement
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• v.18 no.2
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• pp.233-244
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• 2020

Purpose: The study investigated pain and falls as psychological factors in Total Knee Replacement patients and examined the relationship between these factors. Methods: Ninety-six total knee replacement patients aged 69.31±7.01 (male: 21, female: 75) participated in the study. Post-surgery pain was assessed on a visual analog scale, and fall risk scores were evaluated on fall fear and fall efficacy scales. Other psychological factors assessed included national anxiety and trail anxiety, fear prevention, Beck depression score, and psychological health measures. The data were analyzed using SPSS version 22.0. Results: A statistically significant correlation was found between pain before surgery and FES fall fear score before surgery (p < 0.05). A statistically significant correlation was found between pain after surgery and PWBS fall fear score after surgery (p < 0.05). A statistically significant correlation was found between state anxiety and PWBS, Trail anxiety (p < 0.05). A statistically significant correlation was also found between trail anxiety and BDI, PWBS (p < 0.05). State anxiety and fear avoidance before surgery were found to affect trail anxiety, and pain before surgery and fall fear score before surgery were found to affect FES. In addition, PWBS was found to affect BDI. Conclusion: The study confirms that increased pain in Total Knee Replacement patients can be a risk factor for falls. In addition, fall fears increase fear avoidance and cause psychological deterioration. This suggests that efforts should be made to reduce pain and to manage psychological factors.

• Journal of Ginseng Research
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• v.42 no.4
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• pp.540-548
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• 2018

Background: Acute hepatic failure is a life-threatening critical condition associated with rapid deterioration of liver function and liver transplantation. Several studies have shown that Panax ginseng Mayer has antidiabetic and hepatoprotective effects. However, the hepatoprotective effect of ginseng berry is still unveiled. In this study, we evaluated the hepatoprotective effects of ultrasonication-processed ginseng berry extract (UGBE) on acute hepatic failure model in rats. Methods: Ginseng berry extract (GBE) was ultrasonically processed. The GBE, silymarin, and UGBE were orally administered to male Sprague-Dawley rats for 4 wk. Twenty-four h after the last administration, rats were challenged with D-galactosamine (D-GalN)/lipopolysaccharide (LPS). Results: After ultrasonication, the component ratio of ginsenosides Rg2, Rg3, Rh1, Rh4, Rk1, Rk3, and F4 in GBE had been elevated. Administration of UGBE significantly increased the survival rate of D-GalN/LPS-challenged rats. Pretreatment with UGBE significantly decreased serum alanine aminotransferase, aspartate aminotransferase, and total bilirubin levels in D-GalN/LPS-challenged rats in a dose-dependent manner. The levels of enzymatic markers for oxidative stress (superoxide dismutase, glutathione peroxidase, catalase, and glutathione) were increased by UGBE treatment in a dose-dependent manner. Tumor necrosis factor alphalevel, inducible nitric oxide synthase activities, and nitric oxide productions were reduced by UGBE treatment. In addition, hemeoxygenase-1 levels in liver were also significantly increased in the UGBE-treated group. The protein expression of toll-like receptor 4 was decreased by UGBE administration. Hematoxylin and eosin staining results also supported the results of this study showing normal appearance of liver histopathology in the UGBE-treated group. Conclusion: UGBE showed a great hepatoprotective effect on D-GalN/LPS-challenged rats via the toll-like receptor 4 signaling pathway.

• Journal of Convergence for Information Technology
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• v.10 no.11
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• pp.98-106
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• 2020

This study was conducted to identify the factors influencing the severity of pressure injuries of patients with pressure injuries admitted to acute university hospital. This study was a secondary analysis on the data of the study conducted to identify the factors influencing the deterioration of pressure injuries during hospitalization. The data were collected by retrospectively examining the medical records of patients with pressure injuries who were 18 years of age or older and who were admitted to acute university hospital from May 2017 to November 2018. We used data from 472 patients with pressure injuries at admission for this secondary analysis. In order to identify the factor influencing of severe pressure injuries compare to superficial pressure injuries, we analyzed the data using logistic regression analysis. As a result of the study, gender, body temperature, and patient's movement were identified as factors affecting severe pressure injuries. Therefore, special care is necessary to increased the number of position change for inpatients with pressure injuries, especially for patients with decreased mobility.

• Proceedings of the Korea Concrete Institute Conference
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• 2008.04a
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• pp.449-452
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• 2008

This study is to manufacture HSCC (High flowing Self-Compacting Concrete) be able to construction without vibration & hardening, and it is stable according to the change of the surface number of aggregate and to examine the factor of reduction occurred before after hardening through the indoor experiment. It is essential to use of the thickener to increase the viscosity in the combined HSCC. In this result, it make more bubbles than HSCC of pulverulent body. The result of study has shown, through the surface air bubble by not passed air bubbles within concrete after hardening, It has bad effect in not only appearance of structures but strength & duration. It is the experiment for air bubble of concrete according to the types of aggregate (fine aggregate), mixing time of concrete, exfoliation, material of model form and so that reduce the air bubble of combined HSCC. Experiments have shown, the effect of exfoliation was bigger than the effect of form for the performance of surface finishing of combined HSCC after hardening according to the exfoliation or material of model form and the opaque guris has good condition of finishing.

• Genomics & Informatics
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• v.7 no.1
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• pp.20-25
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• 2009

Rheumatoid arthritis (RA) is a chronic autoimmune disorder that is characterized by inflammation of the synovial tissue and deterioration of the joint and bone. A recent study reported a potential gene-environment interaction between HLA-DR and smoking. The present study investigated whether a specific gene was related to the association between smoking and the severity of RA (rheumatoid factor levels > 20 IU/ml). We used the resources of the NARAC family collection of GAW 15 databases, and 1139 subjects with RF>20 IU/ml were included in the current analysis. The linkage panel contained 5858 SNP markers, and 5744 SNPs passed quality control criteria. Linear regression analyses, using PLINK software and generalized estimating equation regression models, were used to test for associations between the SNPs and the severity of RA according to smoking groups. Two major findings were established. First, the severity of RA in smokers was associated with rs703618 (p=$6{\times}10^{-5}$), which lies in the intronic region of the stabilin 2 (STAB2) gene on chromosome 12. Second, there were significant differences in the levels of RF between 'ever smokers' and 'never smokers' according to the rs703618 genotype (G/G, A/G, A/A). We investigated whether a specific gene acts as a mediator between smoking and the severity of RA and found that the STAB2 gene could affect this relationship. Our finding indicates that smoking may mediate RA severity by affecting the expression level of a specific gene.