• Asia Marketing Journal
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• v.13 no.3
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• pp.103-134
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• 2011

The recent economic recession and price rise reduces excessive consumption as a whole. So companies take more interest in and use discount coupons as a means of sales promotion to reinforce their competitiveness. The combination of Internet and mobile communication technology leads to an explosive increase in the use of mobile Internet service, which promotes commercialization of mobile coupons. Nevertheless, there are absolutely insufficient researches on mobile coupons than those on paper ones. In this context, this study tries to consider intention of accepting and using mobile coupons. The innovated Technology Acceptance Model (TAM) was used to see factors of using mobile coupons considered important by customers. Through the combination of characteristics of mobile coupon service and values obtained from mobile coupons, effects of variables to enhance intention of using mobile coupons were empirically analyzed. In particular, this study suggested importance of psychological as well as economic values of mobile coupons and emphasized good considerations of the psychological aspect, such as shame, stinginess, and reputation sensitivity, in using mobile coupons as an important factor for intention of using the coupons. Another empirical analysis was made of what moderating roles consumers' self-construalplayed in the effects of mobile coupon values perceived by consumers on intention of using coupons. As a result, immediate connectivity and situational provision among characteristics of mobile coupon service were found to affect ease and usability. It was also shown that perceived ease and usability had significant effects on both economic and psychological values, which then had significant effects on intention of using a mobile system. After testing moderating effects of self-construal, the degree of effects of perceived mobile coupon values on intention of using mobile coupons was greater among inter-dependent self-construal users than among independent ones. This study considered various schemes of improving intention to use mobile coupons and provided a foundation to help companies make a strategy for mobile coupons to be activated in the future.

• Journal of Life Science
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• v.34 no.7
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• pp.443-452
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• 2024

This study aimed to examine the influence of 3,6-anhydroxygalactose (L-AHG) on the pro-inflammatory M1 polarization and pro-inflammatory responses observed in the RAW264.7 mouse macrophage cell line following stimulation with lipopolysaccharides (LPS). L-AHG exhibited a significant and dose-dependent inhibition of inducible nitric oxide synthase (iNOS) expression, a hallmark of M1 polarization, and subsequent NO production in LPS-stimulated RAW264.7 cells. Furthermore, the LPS-induced upregulation of cyclooxygenase-2 (COX-2), which drives the production of prostaglandin E2, an inflammatory mediator, was also inhibited by L-AHG. L-AHG did not affect the LPS-triggered Toll-like receptor 4 (TLR4)-mediated pro-inflammatory signaling pathway, which culminated in the activation of transforming growth factor-β-activated kinase 1 (TAK1). However, it was observed to inhibit the generation of reactive oxugen species (ROS) in a dose-dependent manner, as well as the TAK1-driven activation of JNK and p38 MAPK. Given that the active p38 MAPK is known to contribute to the assembly of active nicotinamide adenine dinucleotide phosphate (NADPH) oxidase, which catalyzes the intracellular generation of pro-inflammatory ROS in LPS-stimulated macrophages, the dose-dependent reduction in the LPS-induced ROS generation by L-AHG may be mainly due to the prevention of TAK1-driven activation of p38 MAPK. Together, these results demonstrate that the L-AHG-mediated inhibition of the TAK1-JNK/p38 MAPK activation phase of the pro-inflammatory signaling pathway in LPS-stimulated RAW264.7 cells by L-AHG represents a promising mechanism for suppressing M1 polarization and pro-inflammatory responses in macrophages.

• Journal of Biomedical Engineering Research
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• v.24 no.2
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• pp.133-140
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• 2003

In this study, muscle activity was measured using surface EMG (sEMG) during a voluntary maneuver (ankle dorsiflexion) in the supine position was compared pre and post gait training. Nine patients with incomplete spinal cord injury participated in a supported treadmill ambulation training (STAT), twenty minutes a day, five days a week for three months. Two tests, a gait speed test and a voluntary maneuver test, were made the same day, or at least the same week, pre and post gait training. Ten healthy subjects' data recorded using the same voluntary maneuvers were used for the reference. sEMG measured from ten lower limb muscles was used to observe the two features of amplitude and motor control distribution pattern, named response vector. The result showed that the average gait speed of patients increased significantly (p〈0.1) from 0.47$\pm$0.35 m/s to 0.68$\pm$0.52 m/s. In sEMG analysis, six out of nine patients showed a tendency to increase the right tibialis anterior activity during right ankle dorsiflexion from 109.7$\pm$148.5 $mutextrm{V}$ to 145.9$\pm$180.7 $mutextrm{V}$ but it was not significant (p〈0.055). In addition, only two patients showed increase of correlation coefficient and total muscle activity in the left fide during left dorsiflexion. Patients' muscle activity changes after gait training varied individually and generally depended on their muscle control abilities of the pre-STAT status. Response vector being introduced for quantitative analysis showed good Possibility to anticipate. evaluate, and/or guide patients with SCI, before and after gait training.

• The Korean Journal of Pharmacology
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• v.30 no.1
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• pp.137-143
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• 1994

Enhancement or diminution of leukocyte migration to the specific site might be important factors for the development of inflammatory diseases. To investigate the effects of non-steroidal anti-inflammatory drugs (NSAIDs) on chemotaxis of neutrophil, we obtained neutrophils by Hypaque-Ficoll step gradient centrifugation and tested the effects of seven drugs on the n-formyl-leucyl-phenylalanine (FMLP)-induced migration of neutrophil using a 48-well micro chemotaxis assembly. Oxyphenbutazone, phenylbutazone, sulindac, zomepirac, and ibuprofen suppressed the migration of neutrophil at the therapeutic concentrations, however, indomethacin showed stimulation effect. IC50s for inhibition of neutrophil migration by these drugs are less than 100uM. When drugs were preincubated with FMLP, no inhibition on migration of neutrophil was observed. These results indicated that inhibitory effects of these drugs on migration of neutrophil might be related to the receptor sites of neutrophil rather than molecular inactivation of chemoattractant (FMLP). In conclusion, we suggested that the property of inhibition effects on neutrophil migration of several NSAIDs might be another mode of pharmacological action for anti-iflammatory effect, which showed significant effects at concentrations below therapeutic levels, in addition to cyclooxygenase inhibition.

• Journal of Food Hygiene and Safety
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• v.32 no.1
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• pp.8-13
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• 2017

This study was conducted to develop an agent-based computing platform enabling simulation of on-farm produce contamination by enteric foodborne pathogens, which is herein called PPMCS (Preharvest Produce Microbial Contamination Simulator). Also, fecal contamination of preharvest produce was simulated using PPMCS. Although Agent-based Modeling and Simulation, the tool applied in this study, is rather popular in where socio-economical human behaviors or ecological fate of animals in their niche are to be predicted, the incidence of on-farm produce contamination which are thought to be sporadic has never been simulated using this tool. The agents in PPMCS including crop, animal as a source of fecal contamination, and fly as a vector spreading the fecal contamination are given their intrinsic behaviors that are set to be executed at certain probability. Once all these agents are on-set following the intrinsic behavioral rules, consequences as the sum of all the behaviors in the system can be monitored real-time. When fecal contamination of preharvest produce was simulated in PPMCS as numbers of animals, flies, and initially contaminated plants change, the number of animals intruding cropping area affected most on the number of contaminated plants at harvest. For further application, the behaviors and variables of the agents are adjustable depending on user's own scenario of interest. This feature allows PPMCS to be utilized in where different simulating conditions are tested.

• The Korean Journal of Pharmacology
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• v.22 no.1 s.38
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• pp.34-44
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• 1986

In our previous studies, we had clarified many pharmacological effects of majarine: the bacteriostatic effect in vitro; the potentiation of hypnotic action of alcohol; hypotensive effect in rats and hypothermic effect in mice. This study was undertaken to search for a new antihypertensive drug. Red crystalline was obtained from majarine (which was extracted from Berberis koreana Palibin) by chemical methods. And this crystalline was identified as $C_{19}H＿{16}NO＿4$ contained one hydroxy group instead of methoxy group of majarine in isoquinoline ring and named 'Majarol' (5,6-Dihydro-9-hydroxy, 10-methoxybenzo-[g]-1,3-benzodioxolo [5,6-a] quinolizinium). We examined the effects of majarol on blood pressure and heart rate in urethane ancsthetized rats and the rate and amplitude of contraction of isolated frog heart. Several drugs: atropine sulfate, diphenhydramine chloride, hexamethonium bromide, phentolamine, epinephrine, propranolol and isoproterenol were used to clarify the mechanism of the hypotensive action of majarol. The results of experimints were as follows; 1. In low dose (0.5-2mg/kg, i.v.), majarol showed a typical transient hypotensive effect and slight decrease in heart rate. In high dose (5-10 mg/kg, i.v.), majarol showed a typical transient and a subsequent prolonged hypotensive effect and a significant prolonged decrease in heart rate was followed. 2. The hypotensive effects of majarol was not abolished by the pretreatments with atropine sulfate, hexamethonium bromide and diphenhydramine. The pretreatment with phentolamine inhibited significantly the hypotensive effects of majarol and the pretreatment wtih majarol blocked markedly the hypertensive effect of epinephrine. The positive chronotropic effect of isoproterenol was not blocked by the pretreatment with majarol. 3. In low dose, majarol increased the amplitude and decreased rate of contraction, but in high dose, majarol inhibited the amplitude and rate of contraction of isolated frog heart.

• Maxillofacial Plastic and Reconstructive Surgery
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• v.32 no.3
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• pp.218-228
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• 2010

Components of dental resin-based restorative materials are reported to leach from the filling materials even after polymerization. Hydroquinone (HQ) is one of the major monomers used in the dental resin and is known as a carcinogen. Thus, carcinogenic risk of HQ leaching from the dental resin becomes a public health concern. The present study attempted to examine the carcinogenic potentials of HQ on the human epithelial cell, which is the target cell origin of the most of oral cancers. Cytotoxicity of HQ was observed above 50${\mu}M$ as measured by LDH assay, indicating a relatively low toxicity of this substance in human epithelial cells. The parameters of neoplastic cellular transformation such as cell saturation density, soft agar colony formation and cell aggregation were analyzed to examine the carcinogenic potential of HQ. The study showed that 2-week exposure of HQ showed the tendency of increase in the saturation density and the significant enhancement of soft agar colony formation at the highest dose, 50 ${\mu}M$ only. It is suggested that HQ has a weak potential of carcinogenicity. When cells were treated with HQ and TPA, a well-known tumor promoter, the parameters of neoplastic cellular transformation was significantly increased. This result indicates that the potential risk of carcinogenicity from HQ is largely dependent upon the presence of promoter. Exposure of 50 ${\mu}M$ HQ increased the time-dependent apoptosis as measured by the ELISA kit. This concentration coincides with a dose of neoplastic transformation, indicating a possible link between apoptosis and HQ-induced cellular transformation. Hydroquinone generated Reactive Oxygen Species (ROS) which was evidenced by the treatment of antioxidants such as trolox and N-acetyl cysteine and the GSH depleting agent, BSO. Antioxidants blocked the generation of ROS and the GSH depleting agent, BSO dramatically increased the ROS production. Since HQ is known to increase ROS production thru activation of transcriptional factor such as c-Myb and Pim-1, it is speculated that ROS generation by HQ plays a role in the activation of oncogene, which may lead to neoplastic transformation. In addition, ROS is involved in the alteration of signal transduction, which regulates the apoptosis in many cellular systems. Thus, ROS-mediated apoptosis may be involved in the HQ-induced carcinogenic processes. Protein kinase C (PKC) is known to play pivotal roles in neoplastic transformation of cells and its high expression is often found in a variety of types of tumors including oral cancer. PKC translocation of PKC-${\alpha}$ was observed following HQ exposure. Altered signaling system may also play a role in the transformation process. Taken together, HQ leached from the dental resin does not pose a significant threat as a cancer causing agent, but its carcinogenic potential can be significantly elevated in the presence of promoter. The mechanism of HQ-induced carcinogenesis involved ROS generation, apoptosis and altered signaling pathway. The present study will provide a valuable data to estimate the potential risk of HQ as a carcinogen and understand mechanism of HQ-induced carcinogenesis in human epithelial cells.

• Journal of Korea Water Resources Association
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• v.53 no.10
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• pp.845-859
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• 2020

Climate change and recent heat waves have drawn public attention toward other environmental issues, such as water pollution in the form of algal blooms, chemical leaks, and oil spills. Water pollution by the leakage of chemicals may severely affect human health as well as contaminate the air, water, and soil and cause discoloration or death of crops that come in contact with these chemicals. Chemicals that may spill into water streams are often colorless and water-soluble, which makes it difficult to determine whether the water is polluted using the naked eye. When a chemical spill occurs, it is usually detected through a simple contact detection device by installing sensors at locations where leakage is likely to occur. The drawback with the approach using contact detection sensors is that it relies heavily on the skill of field workers. Moreover, these sensors are installed at a limited number of locations, so spill detection is not possible in areas where they are not installed. Recently hyperspectral images have been used to identify land cover and vegetation and to determine water quality by analyzing the inherent spectral characteristics of these materials. While hyperspectral sensors can potentially be used to detect chemical substances, there is currently a lack of research on the detection of chemicals in water streams using hyperspectral sensors. Therefore, this study utilized remote sensing techniques and the latest sensor technology to overcome the limitations of contact detection technology in detecting the leakage of hazardous chemical into aquatic systems. In this study, we aimed to determine whether 18 types of hazardous chemicals could be individually classified using hyperspectral image. To this end, we obtained hyperspectral images of each chemical to establish a spectral library. We expect that future studies will expand the spectral library database for hazardous chemicals and that verification of its application in water streams will be conducted so that it can be applied to real-time monitoring to facilitate rapid detection and response when a chemical spill has occurred.

• Clinical and Experimental Pediatrics
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• v.45 no.5
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• pp.654-658
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• 2002

Purpose : Endocrine and immune systems are connected and interdependent. Adrenal glands play an important role in this network and control the balance between serum levels of dehydroepiandrosterone sulfate(DHEAS) and cortisol. These steroids have an antagonistic effect on the T cell progression into Th1 and Th2 cells and on the induction of correlated interleukins. Therefore we evaluated the role of adrenal androgen and cortisol as immune modulators in Kawasaki disease( KD) with changes of T cell immunity. Methods : From April to August in 2001, we examined serum DHEAS and 24 hour urine free cortisol(F) before administration of immunoglobulin and steroids by radioimmunoassay in 14 KD patients. It's clinical severity was determined by Harada score and coronary lesion. Results : The age of the patient group ranged from 4 months to 4 years; its average age was 2.3 years. Three patients(21.4%) were below 1 year, 2(14.3%) between 1 and 2 years, 5(35.7%) between 2 and 3 years, 4(28.6%) between 3 and 4 years of age. Male to female ratio was 1:1.3. DHEAS was significantly decreased in patients($11.1{\pm}6.0{\mu}g/dL$) more than controls($81.6{\pm}13.3{\mu}g/dL$)(P<0.05). Twenty-four hour urine free cortisol was significantly increased in patients($36.9{\pm}21.9{\mu}g/dL$) more than controls($13.6{\pm}5.5{\mu}g/dL$)(P<0.05). Ratio of DHEAS/F was decreased remarkably in patients($0.33{\pm}0.20$) more than controls($6.65{\pm}2.56$)(P=0.016). There was no difference between ratio of DHEAS/F and Harada score, but its ratio was very low in patients with coronary aneurysm. Conclusion : These data demonstrate that there are changes of DHEAS and cortisol in acute stage of KD and the dis-equilibrium between two steroids may be relevant in the T cell immune response induction of Kawasaki disease. These changes support the use of DHEAS/F ratio as one of the predictive factors of coronary arteries complication.

• Journal of The Korean Association For Science Education
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• v.37 no.5
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• pp.859-877
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• 2017

The purpose of this study is to probe secondary science teachers' perception on scientific models and modeling. A total of 50 experienced science teachers were surveyed with 10 open-ended questions about several aspects of models and modeling: definition, examples, purpose, multiplicity, changeability, design/construction, evaluation and beliefs in the use of models and modeling as a teaching tool. The analysis of the data shows the following results: 1) understanding of models and modeling held by a majority of experienced secondary science teachers was far from that of experts as they concentrated on a model's superficial, representative, and visual functions, 2) when it comes to their view toward the use of a model, a model does not remain in the stage of 'doing science' but in the stage of being a subsidiary teaching tool for the teacher's explaining and the students' understanding of scientific concepts, 3) the subjects they majored in made meaningful differences in their contextual understanding of models and modeling, 4) though most of the teachers acknowledged the importance of teaching about models and modeling, even a lot of them showed a negative position toward the opinion that they are willing to apply modeling to their classes. Implications of the results were discussed in terms of intervention in order to enhance secondary science teachers' understanding and pedagogical content knowledge of models and modeling.