• Molecular & Cellular Toxicology
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• v.4 no.2
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• pp.170-176
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• 2008

The quantitative structure-activity relationship (QSAR) of a set of 35 flavonoid compounds presenting antioxidant activity was established by means of Genetic Algorithm-Multiple Linear Regression (GA-MLR) technique. Four-parametric models for two sets of data, the 1,1-diphenyl-2-picryl hydrazyl (DPPH) radical scavenging activity $(R^2=0.788,\;Q^2_{cv}=0.699\;and\;Q^2_{ext}=0.577)$ and scavenging activity of reactive oxgen species (ROS) induced by $H_2O_2 (R^=0.829,\;Q^2_{cv}=0.754\;and\;Q^2_{ext}=0.573)$ were obtained with low external predictive ability on a mass basis, respectively. Each model gave some different mechanistic aspects of the flavonoid compounds tested in terms of the radical scavenging activity. Topological charge, H-bonding complex and deprotonation processes were likely to be involved in the radical scavenging activity.

• Korean Journal of Human Ecology
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• v.23 no.3
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• pp.467-481
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• 2014

We investigated the effects of Mulberry leaves fermented enzyme liquid(MLE) addition on the quality of Kimchi which were fermented at $5^{\circ}C$ during 30 days. MLE was added to salted cabbage at concentrations of 0%(C), 0.4%(MLE1), 0.8%(MLE2), and 1.2%(MLE3) (w/w). pH in Kimchi added upon 1.2% of MLE, was higher than that of Kimchi without MLE after 12 days of fermentation. The titratable acidity was increased by the addition of MLE, and particularly Kimchi added 1.2% of MLE showed the slowest changed level. The degree of salinity were decreased in Kimchi with MLE as well as control group. However, MLE1 showed significantly lower salinity than MLE2, MLE3 and control group (p<0.001). L, a, b values of control group indicated significantly higher than the Kimchi with enzyme liquid concentrations(MLE1~MLE3). As compared with the control group, the cutting force in treated groups were increased during the fermentation period, and especially MLE3 showed the highest value of hardness. Moreover, that growth of lactic acid bacteria and total bacteria were inhibited by the addition of MLE. In the sensory assessment, the color, taste, and overall preferences were higher in MLE2 than control group and MLE1, MLE3. The acceptability of MLE as an additive in Kimchi among middle school students was higher than in the control sample, with an optimum additive of 0.8% MLE, based on the lowest volume of leftovers. Therefore, it was confirmed that addition of 0.8% MLE appears to be an acceptable approach to enhance the quality of Kimchi without reduction of acceptability.

• International Journal of Oral Biology
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• v.33 no.4
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• pp.143-147
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• 2008

The sodium bicarbonate cotransporter (NBC) protein is functionally expressed in salivary glands. In this experiment, we examined the role of NBC in $HCO_3^-$ formation in human parotid gland acinar cells. Intracellular pH (pHi) was measured in 2'-7'-bis(carboxyethyl)-5(6)-carboxyfluorescein (BCECF)-loaded cells. Acetazolamide (0.1 mM) and 4,4'-diisothio cyanatostilbene-2,2'-disulphonic acid (DIDS, 0.5 mM) were used as specific inhibitors of carbonic anhydrase and NBC, respectively. The degree of inhibition was assessed by measuring the pHi recovery rate (${\Delta}pHi$/min) after cell acidification using an ammonium prepulse technique. In control experiments, ${\Delta}pHi$/min was $1.40{\pm}0.06$. Treatment of cells with 0.5 mM DIDS or 0.1 mM acetazolamide significantly reduced ${\Delta}pHi$/min to $1.14{\pm}0.14$ and $0.74{\pm}0.15$, respectively. Simultaneous application of DIDS and acetazolamide further reduced ${\Delta}pHi$/min to $0.47{\pm}0.10$. Therefore, DIDS and acetazolamide reduced ${\Delta}pHi$/min by 19% and 47%, respectively, while simultaneous application of both DIDS and acetazolamide caused a reduction in ${\Delta}pHi$/min of 67%. These results suggest that in addition to carbonic anhydrase, NBC also partially contributes to $HCO_3^-$ formation in human parotid gland acinar cells.

• Biomedical Science Letters
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• v.8 no.4
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• pp.229-234
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• 2002

Chlorella is rich in chlorella growth factor (CGF). A review of the literature has described that CGF improves the capability of a Th1-based immunity, anticancer, antioxidant antibacterial activity, growth promotion, wound healing and so on, but has not studied the effect for the metabolism and the proliferation of human skin keratinocyte. The aim of this study was to examine the effect of metabolism and the proliferation of human skin keratinocyte in vitro. CGF was extracted with an autoclaving method which is a modified hot-water extraction method from dried chlorella and conformed by means of absorbance 0.22 at 260 nm. We have measured the extracellular acidification rate (ECAR) of the CGF by Cytosensor$^{\circledR}$ Microphysiometer and evaluated responsiveness depending upon the dosage on the HaCaT cell. The ECAR for the concentrations of 0.15, 1.5, 15, 150 $\mu\textrm{g}$/ml of CGF increased as a 103.6, 128.2, 149.0 and 423.9%, respectively compared to control (0.0 $\mu\textrm{g}$/ml, 100% ECAR). The ECAR for ErbBl tyrosine kinase inhibited by 4-anilinoquinazolines, $C_{16}$H$_{14}$BrN$_3$O$_2$.HCl on tile HaCaT cells with the amounts of 10 $\mu\textrm{g}$/ml of the CCF compared with 100 $\mu\textrm{g}$/ml of rhEGF. The conclusion of the study is that CGF might increase human epidermal keratinocyte proliferation through the interaction between the epidermal growth factor receptor and itself.

• Proceedings of the Korean Vacuum Society Conference
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• 2011.02a
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• pp.454-454
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• 2011

Graphene shows unusual electronic properties, such as carrier mobility as high as 10,000 $cm^2$/Vs at room temperature and quantum electronic transport, due to its electronic structure. Carrier mobility of graphene is ten times higher than that of Silicon device. On the one hand, quantum mechanical studies have continued on graphene. One of them is quantum Hall effect which is observed in graphene when high magnetic field is applied under low temperature. This is why two dimension electron gases can be formed on Graphene surface. Moreover, quantum Hall effect can be observed in room temperature under high magnetic field and shows fractional quantization values. Quantum Hall effect is important because quantized Hall resistances always have fundamental value of h/$e^2$ ~ 25,812 Ohm and it can confirm the quantum mechanical behaviors. The value of the quantized Hall resistance is extremely stable and reproducible. Therefore, it can be used for SI unit. We study to measure quantum Hall effect in CVD graphene. Graphene devices are made by using conventional E-beam lithography and RIE. We measure quantum Hall effect under high magnetic field at low temperature by using He4 gas closed loop cryostat.

• Journal of Distribution Science
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• v.16 no.7
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• pp.77-86
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• 2018

Purpose - In the insurance distribution channel, the salespeople plays a role of representing the company, and recognizes the needs of the customers and plays a role in responding to them. Therefore, their turnover can have a great influence on the company performance. The purpose of this study is to investigate the structural relationship between salespeople's personal - environmental fit and organizational commitment and turnover intention. Research design, data, and methodology - Data collection was conducted a self-filling questionnaire for salespeople for about one month from July 24, 2017 to August 30, 2017. The subjects of the questionnaire were the insurance salespeople who work in the sales line such as K life, S fire. A total of 450 copies were distributed and 432 copies of the questionnaire were used for final analysis. The analysis program used SPSS 22.0 and AMOS 22.0 programs. Analysis method was Frequency Analysis, Reliability & Confirmatory Factor Analysis, Correlation Analysis and Structural Equation Model(SEM). Results - As a result of Hypothesis 1, Person-Supervisor Fit had significant influence only on Continuance Commitment. Person-Job Fit did not have a significant effect on Organizational Commitment. Person-Coworker Fit had a significant effect on Continuance Commitment and Affective Commitment. Person-Organization Fit had a significant impact on Affective Commitment. Therefore, only , , , , were adopted. As a result of Hypothesis 2, Continuance Commitment had a significant effect on turnover intention. Therefore, only was adopted. Conclusions - This study suggests that it is necessary to manage the human resources in the sales field through studies related to salespeople's extension of the research scope and salespeople's turnover intention. Based on the results of this study, the conclusion suggests some implications for the efficient human resources management of insurance companies in sales channels. It is expected that it will be helpful for the salespeople to find out what kind of Person-Environment Fit affects the organizational commitment and how to manage the organizational commitment among the three dimensions of organizational commitment to reduce turnover intention.

• Proceedings of the Microbiological Society of Korea Conference
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• 2004.05a
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• pp.47-50
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• 2004

The defenses against free radical damage include specialized repair enzymes that correct oxidative damages in DNA, and detoxification systems such as superoxide dismutases. These defenses may be coordinated genetically as global responses. We hypothesized that the expression of the SOD and the DNA repair genes would inhibit DNA damage under oxidative stress. Therefore, the protection of E. coli mutants deficient in SOD and DNA repair genes $(sod^-\;xth^-\;and\;nfo^-)$ was demonstrated by transforming the mutant strain with a plasmid pYK9 which encoded Photobacterium leiognathi CuZnSOD and human AP endonuclease. The results show that survival rates were increased in $sod^+\;xth^-\;nfo^+$ cells compared to $sod^-\;xth^-\;ap^+,\;sod^-\;xth^-\;ap^-,\;and\;sod^+\;xth^-\;ap^-$ cells under oxidative stress generated from 0.1 mM Paraquat or 3 mM $H_2O_2$. The data suggested that, at least, SOD and DNA repair enzymes may have collaborate protection and repair of the damaged DNA. Additionally, both enzymes are required for protection against free radicals.

• Korean Journal of Human Ecology
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• v.7 no.2
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• pp.113-119
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• 1998

The purpose of this study was to investigate the effect of geometrical structure on the heat transfer of insulating nonwovens. Commercially available single and double layered polyester nonwovens have used. Thermal conductivity, k and thermal conductance, h were measured by using a constant temperature sandwich type device at dry and wet state. The results obtained were as follows: 1. Double layered nonwovens showed slightly lower thermal conductance and higher warmability than single layered nonwovens. 2. As moisture regain increased, double layered nonwovens showed higher increasing rate of thermal conductivity than single layered nonwovens.

• Journal of The Korean Dental Society of Anesthesiology
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• v.14 no.3
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• pp.157-165
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• 2014

Background: Incisional site of surgical operation become transient ischemic state and then occur reoxygenation due to vasodilatation by inflammatory reaction, the productive reactive oxygen species (ROS) give rise to many physiologic results. Apoptosis have major role on elimination of inflammatory cell and formation of granulation tissue in normal wound healing process. Remifentanil can prevent the inflammatory response and can suppress inducible nitric oxide synthase expression in a septic mouse model. After cardiopulmonary bypass for coronary artery surgery, remifentanil can also inhibit the release of biomarkers of myocardial damage. Here we investigated whether remifentanil pretreatment has cellular protective effect against hypoxia-reoxygenation in HaCaT human keratinocytes, if so, the role of apoptosis and autophagy on this phenomenon. Methods: The HaCaT human keratinocytes were exposed to various concentrations of remifentanil (0.01, 0.05, 0.1, 0.5 and 1 ng/ml) for 2 h before hypoxia (RPC/HR group). These cells were cultured under 1% oxygen tension for 24h at $37^{\circ}C$. After hypoxia, to simulate reoxygenation and recovery, the cells were reoxygenated for 12 h at $37^{\circ}C$. 3-MA/RPC/HR group was treated 3-methyladenine (3-MA), autophagy inhibitor for 1h before remifentanil treatment. Cell viability was measured using a quantitative colorimetric assay with thiazolyl blue tetrazoliumbromide (MTT, amresco), showing the mitochondrial activity of living cells. To investigate whether the occurrence of autophagy and apoptosis, we used fluorescence microscopy and Western blot analysis. Results: The viability against hypoxia-reoxygenation injury in remifentanil preconditioning keratinocytes were increased, and these cells were showed stimulated expression of autophagy 3-MA suppressed the induction of autophagy effectively and the protective effects on apoptosis. Atg5, Beclin-1, LC3-II and p62 were elevated in RPC/HR group. But they were decreased when autophagy was suppressed by 3-MA. Conclusions: Remifentanil preconditioning showed the protective effect in human keratinocytes, and we concluded that autophagy may take the major role in the recovery of wound from hypoxia-reoxygenation injury. We suggest that further research is needed about the cell protective effects of autophagy.

• Food Science of Animal Resources
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• v.24 no.1
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• pp.86-91
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• 2004

The ability of probiotics containing Lactobacillus acidophilus to adhere to the intestinal epithelium may play an important role in colonization of the gastrointestinal tract and preventing enteric pathogen such as enterohemorrhagic E. coli(EHEC O157:H7. In the study, we investigated the adhesion to human intestinal epithelial cells(HT-29) of strains of L. acidophilus(3 from human, 2 from pig, and 1 from calf). All of the tested strains of L. acidophilus were highly observed adhesion ability(from 10$\^$6/ to 10$\^$7/ cfu/mL), compared to L. rhamnosus GG as control. Also, adhered strains of L. acidophilus were significantly preserved in serial wash-out steps. However, no correlation could be observed between cell surface hydrophobicity and adhesion abilities of the tested strains of L. acidophilus. Inhibition of adhesion of EHEC O157:H7 was also examined, a 2 log cycle reduction was observed by all of the tested strains of L. acidophilus. These results suggest that the strains of L. acidophilus with high adhesion ability are resistant to wash-out and adhesion ability inhibition by selected strains of L. acidophilus helps to prevent adhesion of EHEC O157:H7 to intestinal epithelial cells.