• Korean Journal of Food Science and Technology
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• v.51 no.4
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• pp.379-392
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• 2019

The current study investigated the effect of Gabjubaekmok (Diospyros kaki) ethanolic extract (GEE) on $H_2O_2$-induced human neuroblastoma MC-IXC cells and amyloid beta $(A{\beta})_{1-42}$-induced ICR (Institute of Cancer Research) mice. GEE showed significant antioxidant activity that was evaluated based on ABTS, DPPH scavenging activity, and inhibition of malondialdehyde (MDA) and acetylcholinesterase activity. Further, GEE inhibited ROS production and increased cell viability in $H_2O_2$-induced MC-IXC cells. Administration of GEE ameliorated the cognitive dysfunction on $A{\beta}$-induced ICR mice as evaluated using Y-maze, passive avoidance, and Morris water maze tests. Results of ex vivo test using brain tissues showed that, GEE protected the cholinergic system and mitochondrial functions by increasing the levels of antioxidants such as ROS, mitochondrial membrane potential (MMP), and adenosine triphosphate (ATP) against $A{\beta}$-induced cognitive dysfunction. Moreover, GEE decreasd the expression levels of apoptosis-related proteins such as $TNF-{\alpha}$, p-JNK, p-tau, BAX and caspase 3. While, expression levels of p-Akt and $p-GSK3{\beta}$ increased than $A{\beta}$ group. Finally, gallic acid was identified as the main compound of GEE using high performance liquid chromatography.

• Journal of Environmental Impact Assessment
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• v.30 no.1
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• pp.35-48
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• 2021

In this study, the assessment of field applicability of in-situ remediation of nitrate-contaminated groundwater located in Yesan-gun was performed. Zero-valent iron/bio composite media injected PRB (Permeable Reactive Barrier) and monitoring well were installed in the contaminated groundwater site and monitored main remediation indicators during the PRB operation. Nitrate, nitrite, ammonia, Fe ion, TOC, and turbidity were analyzed and the diversity and population of microorganism in the PRB installed site were investigated for the verification of effect of injected PRB. In the study site where is an agricultural area, a river flows from west to east that forms a river boundary and the southern area has an impermeable sector. It was found that nitrate flows into the river, which is similar as groundwater flow. Simulation result for the fate of nitrate in groundwater showed steady state of nitrate arrived after 3~5 years passed. However, it is just to consider current conditions with no additional input of contaminant source, if additional input of contaminant source occurs contamination dispersion and time for steady state are expected to be increased. The monitoring results showed that Fe ion, TOC and turbidity in groundwater were not clearly changed in concentration after PRB installation, which indicates adaptability of the injected PRB for remediation of groundwater with no additional harmful effect to water quality. The concentration of nitrate maintained less than 5mg/L until 42 days after PRB installation and recovered its initial concentration after 84 days passed and showed termination of reactivity of injected zero-valent iron/bio composite media for removal nitrate. Nitrite and ammonia ions found after installation of PRB indicates reductive removal of nitrate. And the outstanding increase of microorganism diversity and population of Betaproteobacteria Class which includes denitrification microorganism explains biologically reductive removal of nitrate in injected PRB.

• Journal of Dental Rehabilitation and Applied Science
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• v.38 no.3
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• pp.150-161
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• 2022

Purpose: To determine the effects of the microgroove-fibronectin complex surface on the expression of various genes related to cellular activity in human gingival fibroblasts. Materials and Methods: Smooth titanium specimens (NE0), acid-treated titanium specimens (E0), microgroove and acid-treated titanium specimens (E60/10), fibronectin-fixed smooth titanium specimens (NE0FN), acid-treated and fibronectin-immobilized titanium specimens (E0FN), and microgroove and acid-treated titanium specimens immobilized with fibronectin (E60/10FN) were prepared. Real-time polymerase chain reaction experiments were conducted on 44 genes related to cell behavior of human gingival fibroblasts. Results: Adhesion and proliferation of human gingival fibroblast on microgroove-fibronectin complex titanium were activated through four types of signaling pathway. Integrin α5, Integrin β1, Integrin β3, Talin-2, which belong to the focal adhesion pathway, AKT1, AKT2, NF-κB, which belong to the PI3K-AKT signaling pathway, MEK2, ERK1, ERK2, which belong to the MAPK signaling pathway, and Cyclin D1, CDK4, CDK6 genes belonging to the cell cycle signaling pathway were upregulated on the microgroove-fibronectin complex titanium surface (E60/10FN). Conclusion: The microgroove-fibronectin complex titanium surface can up-regulate various genes involved in cell behavior.

• The Korean Journal of Pharmacology
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• v.16 no.1 s.26
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• pp.25-34
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• 1980

The in vitro guinea pig ureter responded to 5 sec trains of electrical stimuli with two contractions; the first an 'on response' (ON) occurred with $0.1{\sim}0.3$ sec after the onset o the stimulus train, the second an 'off response'(OFF) occurred $0.2{\sim}1.0$ sec after the termination of the stimulus train. Relaxation occurred between the two responses during a time when the stimulus was still being delivered. Longer duration and/or higher frequencies of stimuli within the train were required to elicit the OFF than the ON. Decreasing temperature from $37^{\circ}$ to $22^{\circ}$ decreased ON amplitude and increased OFF amplitude. $Ca^{++}$-free solution, 2 mM EDTA, 1 mM $Mn^{++}$ or $1{\mu}M$ verapamil rapidly abolished ON. OFF persisted when ON had disappeared by repeated stimulation at 0.12 train per sec. Conversely, caffeine, $50{\mu}M$ and theophylline, $10{\mu}M$ abolished OFF with only slight reduction of ON, and sodium nitroprusside decreased preferentially ON amplitude rather than OFF. Relaxation between ON and OFF was incomplete in low $Na^+$ solution. ON and OFF were not affected by the neural blockers tetrodotoxin, atropine or phentolamine, also pyrilamine and methysergide, and relaxation between ON and OFF was $Na^+$ dependent. Furthermore, ON depends on free $Ca^{++}$ and OFF is more dependent on bound or stored $Ca^{++}$.

• Journal of Popular Narrative
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• v.25 no.3
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• pp.349-383
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• 2019

This paper examined the meaning and task of romance research with a focus on Reading the Romance(1984) by Janice A. Radway. This book, which analyzes romance texts by examining the situation and meaning of reading romance by women readers integrating between cultural studies and literary studies, is one of the most popular studies on the romance genre. Radway scrutinized the practical significance of reading romance in a community of women readers. Through a study involving questionnaires and in-depth interviews, she found that for women, romance reading is a 'compensatory fiction' that brings happiness and emotional redemption through a sense of liberation achieved by escaping from patriarchal daily life. The romance that women prefer is composed of 4 stages and 13 divisions: 'Encounter → Attest → Recovery → Happy End'. It also maintains a formula that begins with an immature female character's identity crisis and ends with a blissful union that recognizes the intrinsic value of the main character, who has turned into a man who is considerate of the women. Therefore, romance plays the role of pursuit of the 'female utopian fantasy' and at the same time a reconciliation of women to patriarchy. Feminist critics of the day criticized this argument. However, reading romance is a 'feminine reading', and romance is literature about the functional relationship between women's lives and patriarchy. Yet the interpretation could differ depending on the different viewpoints and definitions of the women's utopian fantasy. In recent years, the conditions of female reader's lives, awareness and imagination have been changing rapidly. As a result, the female utopian fantasy has also changed significantly. Nevertheless, women's lives in the real patriarchal system are still contradictory, and their adventurous imagination is spreading in alternative spaces such as the subculture. In this regard, the question is about the definition of romance and the meanings of romance research are still important task.

• Korean Journal of Breeding Science
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• v.51 no.3
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• pp.190-200
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• 2019

It is reported that the absence of lipoxygenase-3 (LOX-3) may contribute to a reduction in stale flavor after the storage of rice. To improve the quality of stored rice of the Korean japonica rice cultivar, we conducted a breeding program to develop near-isogenic rice without LOX-3 in the genetic background of Saenuri, a mega variety of Korea. In the first step of the breeding program, we used a donor parent of LOX-3 null, Daw Dam, and a recurrent japonica parent, Sindongjin, to develop HR27873-AC12 by backcross (BC₁), color test for introgression of lox-3, and anther culture for rapid fixation. In the second step, we used the donor parent, HR27873-AC12, and the recurrent parent, Saenuri, to develop HR28896-31-3-1-1 by backcross (BC₁), marker-assisted selection (MAS) for lox-3, and phenotypic selection (PS) for agronomic traits. Finally, in the third step, we developed HR30960-186-2-1-2-1 (Jeonju624), derived from a cross between Saenuri and HR28896-31-3-1-1, by MAS for lox-3 and PS with high selection pressure for agronomic characteristics. Jeonju624 was confirmed with the introgression of lox-3 by molecular marker. Jeonju624 was a mid-late maturing rice with similar agronomic characteristics to Saenuri, lodging tolerance with short culm, erect plant architecture, and resistance to bacterial blight and rice stripe virus. The yield components of Jeonju624 were mostly similar to Saenuri, except for the 1,000-grain weight of brown rice. The appearance of the grain of Jeonju624 was better than that of Saenuri, and the characteristics of cooked rice were similar to those of Saenuri. In the genetic background analysis using 406 KASP (Kompetitive Allele-Specific PCR) markers, Jeonju624 was confirmed to be the near-isogenic line (NIL) of Saenuri with a 95.8% recovery rate. Jeonju624 is the NIL of Saenuri without LOX-3, and overcomes the linkage drag of Daw Dam with similar agronomic characteristics and genetic background to Saenuri. Jeonju624 can be utilized as a practical cultivar to improve the quality of stored rice, breeding material for the introgression of lox-3, and genetic material to elucidate the effect of introgressed genes.

• Journal of Dental Rehabilitation and Applied Science
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• v.40 no.1
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• pp.13-23
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• 2024

Purpose: This aim of this study was to demonstrate growth factors that differentiate human mesenchymal stem cells into chondrocytes and to evaluate cell proliferation enhancement by needle size differences. Materials and Methods: Human mesenchymal stem cells were cultured in chondrogenic medium supplemented with BMP-2, BMP-4, BMP-6, BMP-7, BMP-13, FGF-2, FGF-18, IGF-1, TGF-β1, TGF-β2, TGF-β3 and without growth factors for 14, 21, and 28 days. Then, the expression levels of SOX-5, SOX-6, SOX-9 and FOXO1A were comparatively analyzed. Human mesenchymal stem cells were inoculated into culture dishes using 18, 21, and 26 gauge (G) needles, and cell proliferation was measured after 24, 48, and 72 hours, respectively. Results: In addition to the previously known FGF, IGF-1, and TGFβ1,the BMP family growth factors such as BMP-2, BMP-4, BMP-6, and BMP-7 increased the expression of chondrocyte differentiation genes SOX-5, SOX-6, SOX-9, and FOXO1A. At 48 hours, the 26G group, the smallest needle, showed significant cell proliferation improvement compared to the control group and the 18G group. At 72 hours, the 26G group, the smallest needle, showed significant increase in cell proliferation compared to the control group. Conclusion: Through this study, growth factors with the ability to induce chondrocyte differentiation of human mesenchymal stem cells were investigated, and cell proliferation changes by needle size differences were determined.

• The Sea:JOURNAL OF THE KOREAN SOCIETY OF OCEANOGRAPHY
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• v.15 no.1
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• pp.8-15
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• 2010

An experiment was conducted to evaluate the biologically adverse effect of increased carbon dioxide in seawater on marine bacteria, Vibrio fischeri. We measured the bioluminescence and cell density at every 6 hours for 24 hours of the whole incubation period after exposing test microbes to a range of $CO_2$ concentration such as 380(Control), 1,000, 3,000, 10,000 and 30,000 ppm, respectively. Significant effect on relative luminescence(RLU) of V. fischeri was observed in treatments with $CO_2$ concentration higher than 3,000 ppm at t=12 h. However, the difference of RLU among treatments significantly decreased with the incubation time until t=24 h. Similar trend was observed for the variation of cell density, which was measured as optical density using spectrophotometer. The results showed that a significant relationship between $CO_2$ concentration and bioluminescence of test microbes was observed for the mean time. However, the inhibition of relative bioluminescence and also cell density could be recovered at the concentration levels higher than 3,000 ppm. The dissolved $CO_2$ can be absorbed directly by cell and it can decrease the intracellular pH. Our results implied that microbes might be adversely affected at the initial growing phase by increased $CO_2$. However, they could adapt by increasing ion transport including bicarbonate and then could make their pH back to normal level. Results of this study could be supported to understand the possible influence on marine bacteria by atmospheric increase of $CO_2$ in near future and also by released $CO_2$ during the marine $CO_2$ sequestration activity.

• Journal of Distribution Research
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• v.15 no.3
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• pp.71-110
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• 2010

1. Introduction Today Internet is recognized as an important way for the transaction of products and services. According to the data surveyed by the National Statistical Office, the on-line transaction in 2007 for a year, 15.7656 trillion, shows a 17.1%(2.3060 trillion won) increase over last year, of these, the amount of B2C has been increased 12.0%(10.2258 trillion won). Like this, because the entry barrier of on-line market of Korea is low, many retailers could easily enter into the market. So the bigger its scale is, but on the other hand, the tougher its competition is. Particularly due to the Internet and innovation of IT, the existing market has been changed into the perfect competitive market(Srinivasan, Rolph & Kishore, 2002). In the early years of on-line business, they think that the main reason for success is a moderate price, they are awakened to its importance of on-line service quality with tough competition. If it's not sure whether customers can be provided with what they want, they can use the Web sites, perhaps they can trust their products that had been already bought or not, they have a doubt its viability(Parasuraman, Zeithaml & Malhotra, 2005). Customers can directly reserve and issue their air tickets irrespective of place and time at the Web sites of travel agencies or airlines, but its empirical studies about these Web sites for reserving and issuing air tickets are insufficient. Therefore this study goes on for following specific objects. First object is to measure service quality and service recovery of Web sites for reserving and issuing air tickets. Second is to look into whether above on-line service quality and on-line service recovery have an impact on overall service quality. Third is to seek for the relation with overall service quality and customer satisfaction, then this customer satisfaction and loyalty intention. 2. Theoretical Background 2.1 On-line Service Quality Barnes & Vidgen(2000; 2001a; 2001b; 2002) had invented the tool to measure Web sites' quality four times(called WebQual). The WebQual 1.0, Step one invented a measuring item for information quality based on QFD, and this had been verified by students of UK business school. The Web Qual 2.0, Step two invented for interaction quality, and had been judged by customers of on-line bookshop. The WebQual 3.0, Step three invented by consolidating the WebQual 1.0 for information quality and the WebQual2.0 for interactionquality. It includes 3-quality-dimension, information quality, interaction quality, site design, and had been assessed and confirmed by auction sites(e-bay, Amazon, QXL). Furtheron, through the former empirical studies, the authors changed sites quality into usability by judging that usability is a concept how customers interact with or perceive Web sites and It is used widely for accessing Web sites. By this process, WebQual 4.0 was invented, and is consist of 3-quality-dimension; information quality, interaction quality, usability, 22 items. However, because WebQual 4.0 is focusing on technical part, it's usable at the Website's design part, on the other hand, it's not usable at the Web site's pleasant experience part. Parasuraman, Zeithaml & Malhorta(2002; 2005) had invented the measure for measuring on-line service quality in 2002 and 2005. The study in 2002 divided on-line service quality into 5 dimensions. But these were not well-organized, so there needed to be studied again totally. So Parasuraman, Zeithaml & Malhorta(2005) re-worked out the study about on-line service quality measure base on 2002's study and invented E-S-QUAL. After they invented preliminary measure for on-line service quality, they made up a question for customers who had purchased at amazon.com and walmart.com and reassessed this measure. And they perfected an invention of E-S-QUAL consists of 4 dimensions, 22 items of efficiency, system availability, fulfillment, privacy. Efficiency measures assess to sites and usability and others, system availability measures accurate technical function of sites and others, fulfillment measures promptness of delivering products and sufficient goods and others and privacy measures the degree of protection of data about their customers and so on. 2.2 Service Recovery Service industries tend to minimize the losses by coping with service failure promptly. This responses of service providers to service failure mean service recovery(Kelly & Davis, 1994). Bitner(1990) went on his study from customers' view about service providers' behavior for customers to recognize their satisfaction/dissatisfaction at service point. According to them, to manage service failure successfully, exact recognition of service problem, an apology, sufficient description about service failure and some tangible compensation are important. Parasuraman, Zeithaml & Malhorta(2005) approached the service recovery from how to measure, rather than how to manage, and moved to on-line market not to off-line, then invented E-RecS-QUAL which is a measuring tool about on-line service recovery. 2.3 Customer Satisfaction The definition of customer satisfaction can be divided into two points of view. First, they approached customer satisfaction from outcome of comsumer. Howard & Sheth(1969) defined satisfaction as 'a cognitive condition feeling being rewarded properly or improperly for their sacrifice.' and Westbrook & Reilly(1983) also defined customer satisfaction/dissatisfaction as 'a psychological reaction to the behavior pattern of shopping and purchasing, the display condition of retail store, outcome of purchased goods and service as well as whole market.' Second, they approached customer satisfaction from process. Engel & Blackwell(1982) defined satisfaction as 'an assessment of a consistency in chosen alternative proposal and their belief they had with them.' Tse & Wilton(1988) defined customer satisfaction as 'a customers' reaction to discordance between advance expectation and ex post facto outcome.' That is, this point of view that customer satisfaction is process is the important factor that comparing and assessing process what they expect and outcome of consumer. Unlike outcome-oriented approach, process-oriented approach has many advantages. As process-oriented approach deals with customers' whole expenditure experience, it checks up main process by measuring one by one each factor which is essential role at each step. And this approach enables us to check perceptual/psychological process formed customer satisfaction. Because of these advantages, now many studies are adopting this process-oriented approach(Yi, 1995). 2.4 Loyalty Intention Loyalty has been studied by dividing into behavioral approaches, attitudinal approaches and complex approaches(Dekimpe et al., 1997). In the early years of study, they defined loyalty focusing on behavioral concept, behavioral approaches regard customer loyalty as "a tendency to purchase periodically within a certain period of time at specific retail store." But the loyalty of behavioral approaches focuses on only outcome of customer behavior, so there are someone to point the limits that customers' decision-making situation or process were neglected(Enis & Paul, 1970; Raj, 1982; Lee, 2002). So the attitudinal approaches were suggested. The attitudinal approaches consider loyalty contains all the cognitive, emotional, voluntary factors(Oliver, 1997), define the customer loyalty as "friendly behaviors for specific retail stores." However these attitudinal approaches can explain that how the customer loyalty form and change, but cannot say positively whether it is moved to real purchasing in the future or not. This is a kind of shortcoming(Oh, 1995). 3. Research Design 3.1 Research Model Based on the objects of this study, the research model derived is