• Journal of the Korean institute of surface engineering
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• v.46 no.2
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• pp.68-74
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• 2013

For the coating of diamond films on WC-Co tools, a buffer interlayer is needed because Co catalyzes diamond into graphite. W and Ti were chosen as candidate interlayer materials to prevent the diffusion of Co during diamond deposition. W or Ti interlayer of $1{\mu}m$ thickness was deposited on WC-Co substrate under Ar in a DC magnetron sputter. After seeding treatment of the interlayer-deposited specimens in an ultrasonic bath containing nanometer diamond powders, $2{\mu}m$ thick nanocrystalline diamond (NCD) films were deposited at $600^{\circ}C$ over the metal layers in a 2.45 GHz microwave plasma CVD system. The cross-sectional morphology of films was observed by FESEM. X-ray diffraction and visual Raman spectroscopy were used to confirm the NCD crystal structure. Micro hardness was measured by nano-indenter. The coefficient of friction (COF) was measured by tribology test using ball on disk method. After tribology test, wear tracks were examined by optical microscope and alpha step profiler. Rockwell C indentation test was performed to characterize the adhesion between films and substrate. Ti and W were found good interlayer materials to act as Co diffusion barriers and diamond nucleation layers. The COFs on NCD films with W or Ti interlayer were measured as less than 0.1 whereas that on bare WC-Co was 0.6~1.0. However, W interlayer exhibited better results than Ti in terms of the adhesion to WC-Co substrate and to NCD film. This result is believed to be due to smaller difference in the coefficients of thermal expansion of the related films in the case of W interlayer than Ti one. By varying the thickness of W interlayer as 1, 2, and $4{\mu}m$ with a fixed $2{\mu}m$ thick NCD film, no difference in COF and wear behavior but a significant change in adhesion was observed. It was shown that the thicker the interlayer, the stronger the adhesion. It is suggested that thicker W interlayer is more effective in relieving the residual stress of NCD film during cooling after deposition and results in stronger adhesion.

• Korean Journal of Veterinary Research
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• v.60 no.1
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• pp.25-32
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• 2020

Natural killer (NK) cells play have a crucial role in the early phase of immune responses against various pathogens. We compared characteristics of canine NK cells against two canine mammary carcinoma cell lines, REM134 and CF41.Mg. REM134 showed higher expression of progesterone receptor, proliferative cell nuclear antigen, Ki67, multiple drug resistance, Bmi-1, c-myc, E-cadherin, and human epidermal growth factor receptor type-2 than that of CF41.Mg. For specific expansion and activation of NK cells, we isolated CD5 negative cells from canine peripheral blood mononuclear cells and co-cultured K562 cells in the presence of interleukin (IL)-2, IL-15, and IL-21 for 21 days. As a result, we found that expression markers of activated NK cells such as NKp30, NKp44, NKp46, NKG2D, CD244, perforin, granzyme B, and tumor necrosis factor alpha were highly upregulated. In addition, we found there was upregulated production of interferon gamma of activated NK cells against target cells such as REM134 and CF41.Mg. Specifically, we observed that cytotoxicity of NK cells against target cells was more sensitively reacted to CF41.Mg than REM134. Based on the results of this study, we recommend the development of an experimental application of CF41Mg, which has not been reported in canine mammary carcinoma research.

• Korean Journal of Poultry Science
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• v.49 no.2
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• pp.125-137
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• 2022

This study aimed to determine the effects of dietary microalgae (Tetradesmus sp. (TO)) on intestinal immunity and microbiota of pre-starter broilers. One hundred and twenty 1-day-old birds (Ross 308) were allocated to two dietary treatment groups with six blocks in a randomized complete block design. The two experimental diets consisted of a corn-soybean meal-based basal diet and a diet with 0.5% TO powder instead of cornstarch in the basal diet. After feeding the experimental diets for ten days, all birds' body weight and feed intake were measured, and representative eight birds were selected from each treatment group. Small intestinal lamina propria cells were isolated using flow cytometry to examine the frequency of immune cells. Cecal feces were harvested for 16s rRNA gut microbiota analysis and fecal IgA levels. Here, we found that 0.5% TO supplementation increased CD3⁺CD4⁺ T cells in the small intestine, but decreased CD3⁺CD8⁺ T cells in the small intestine. Gut microbial analysis showed that TO supplementation significantly increased the alpha diversity of the gut microbiome. Taxonomic analysis showed that TO treatment increased the abundance of Firmicutes and decreased that of Bacteroidetes at the phylum level. The distribution of Enterobacteriaceae containing many harmful bacteria at the family level, was lower in the TO group. In the LEfSe analysis, the TO group had a significantly enriched abundance of Agathobaculum at the genus level. Overall, results show that Tetradesmus sp. supplementation influences intestinal T-cell immunity and induces the expansion of beneficial gut microbes in pre-starter broiler chickens.

• Journal of Internet Computing and Services
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• v.24 no.1
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• pp.71-86
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• 2023

The purpose of this exploratory study is to compare the differences in public perceptual characteristics of Korean and Chinese societies regarding the metaverse using big data analysis. Due to the environmental impact of the COVID-19 pandemic, technological progress, and the expansion of new consumer bases such as generation Z and Alpha, the world's interest in the metaverse is drawing attention, and related academic studies have been also in full swing from 2021. In particular, Korea and China have emerged as major leading countries in the metaverse industry. It is a timely research question to discover the difference in social awareness using big data accumulated in both countries at a time when the amount of mentions on the metaverse has skyrocketed. The analysis technique identifies the importance of key words by analyzing word frequency, N-gram, and TF-IDF of clean data through text mining analysis, and analyzes the density and centrality of semantic networks to determine the strength of connection between words and their semantic relevance. Python 3.9 Anaconda data science platform 3 and Textom 6 versions were used, and UCINET 6.759 analysis and visualization were performed for semantic network analysis and structural CONCOR analysis. As a result, four blocks, each of which are similar word groups, were driven. These blocks represent different perspectives that reflect the types of social perceptions of the metaverse in both countries. Studies on the metaverse are increasing, but studies on comparative research approaches between countries from a cross-cultural aspect have not yet been conducted. At this point, as a preceding study, this study will be able to provide theoretical grounds and meaningful insights to future studies.

• IMMUNE NETWORK
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• v.3 no.1
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• pp.1-7
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• 2003

Type II collagen (CII), major component of hyaline cartilage, has been considered as an auto-antigen in rheumatoid arthritis (RA). However, the clinical and biological significances with regard to the CII autoimmunity need to be clarified in human RA. The presence of antibodies to CII has been identified in sera, synovial fluid, and cartilage of patients with RA. In our study, the increased titer of IgG anti-CII in sera was well correlated with C-reactive protein, suggesting that this antibody may reflect the inflammatory status of RA. The titer of anti-CII antibodies (anti-CII Abs) tended to be higher in early stages of diseases. In our extending study, among 997 patients with RA, 269 (27.0%) were positive for circulatory IgG antibody to CII, those levels were fluctuated over time. It is hard to assess the significant amount of T cell responses to CII and CII (255~274) in RA. By using a sensitive method of antigen specific mixed lymphocyte culture, we can detect the presence of CII-reactive T cells in peripheral blood mononuclear cells of RA patients. Sixty seven (46.9%) of 143 patients showed positive CII reactive T cell responses to CII or CII (255~274). The frequencies of CII reactive T cells were more prominent in inflamed synovial fluid (SF) than in peripheral blood. These T cells could be clonally expanded after consecutive stimulation of CII with feeding of autologous irradiated antigen presenting cells (APC). Moreover, the production of Th1-related cytokine, such as IFN-${\gamma}$, was strongly up-regulated by CII reactive T cells. These data suggest that T cells responding to CII, which are probably presenting the IFN-${\gamma}$ producing cells, may play an important role in the perpetuation of inflammatory process in RA. To evaluate the effector function of CII reactive T cells, we investigated the effect of CII reactive T cells and fibroblasts-like synoviocytes (FLS) interaction on the production of pro-inflammatory cytokines. When the CII reactive T cells were co-cultured with FLS, the production of IL-15 and TNF-${\alpha}$ from FLS were significantly increased (2 to 3 fold increase) and this increase was clearly presented in accord to the expansion of CII reactive T cells. In addition, the production of IFN-${\gamma}$ and IL-17, T cell derived cytokines, were also increased by the co-incubation of CII reactive T cells with FLS. We also examined the impact of CII reactive T cells on chemokines production. When FLS were co-cultured with CII stimulated T cells, the production of IL-8, MCP-1, and MIP-1${\alpha}$ were significantly enhanced. The increased production of these chemokines was strongly correlated with increase the frequency of CII reactive T cells. Conclusively, immune response to CII was frequently found in RA. Activated T cells in response to CII contributed to increase the production of proinflammatory cytokines and chemokines, which were critical for inflammatory responses in RA. The interaction of CII-reactive T cells with FLS further augmented this phenomenon. Taken together, our recent studies have suggested that autoimmunity to CII could play a crucial role not only in the initiation but amplification/perpetuation of inflammatory process in human RA.

• IMMUNE NETWORK
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• v.5 no.2
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• pp.78-88
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• 2005

Background: Collagen-induced arthritis (CIA) in mice is animal model of autoimmune disease known as rheumatic arthritis in human. We investigated CII-specific CD4+ T cell receptor usage in CIA mice. Methods: In CIA model, draining lymph node (dLN) CD4+ T cells and splenocytes at $3^{rd},\;5^{th},\;8^{th}$ week, we investigated CII-specific T cell proliferation, production of IL-17, IFN-${\gamma}$, TNF-${\alpha}$, IL-4 and IL-10. And we also performed anti-CII IgG Ab measurements in serum level, TCRV ${\beta}$ usage and T cell clonality with RT-PCR-SSCP analysis. Also, we performed proliferative response against CII when CII-specific T cell subset is deleted. Results: CIA mice showed more increase in the serum level of anti-CII IgG than normal mice after induction of arthritis. And the level of anti-CII IgG2a in CIA mice was increased after $3^{rd}$ week after primary immunization, while anti-CII IgG1 was decreased. Draining LN CD4+ T cells have proliferated against CII stimulation at $3^{rd}$ week after $1^{st}$immunization. CD4+T cells derived from dLN of CIA mice produced proinflammatory cytokine IFN-${\gamma}$, IL-17 etc. Draining LN CD4 T cells of CIA presented higher proportion of CD4+V ${\beta}3$+subset compared to those of normal mice at $3^{rd}$ week after $1^{st}$ immunization, and they were increased in proportion by CII stimulation. Draining LN CD4+ T cells without TCRV ${\beta}3+/V{\beta}8.1/8.2+/V{\beta}$10b+cells were not responsive against CII stimulation. But, CII-reactive response of TCRV ${\beta}3-/V{\beta}8.1/8.2-/V{\beta}$10b- T cells was recovered when $V{\beta}3+$ T cells were added in culture. Conclusion: Our results indicate that CD4+$V{\beta}3+$ T cells are selectively expanded in dLN of CIA mice, and their recovery upon CII re-stimulation in vitro, as well as the production Th1-type cytokines, may play pivotal role in CIA pathogenesis.

• Journal of the Korean Society of Food Science and Nutrition
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• v.42 no.11
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• pp.1848-1856
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• 2013

This study is designed to examine the change in physical properties of extruded brown rice-vegetable mix at different temperatures and $CO_2$ gas injections. Moisture content and screw speed were fixed to 27% and 100 rpm respectively. Die temperatures and $CO_2$ gas injections were adjusted to 60, 80, $100^{\circ}C$ and 0, 150 mL/min, respectively. The ratio of ${\alpha}$-brown rice, brown rice and sugars (oligosaccharides and palatinose) was fixed to 25, 50 and 16%, respectively. Green tea, tomato and pumpkin powder were blended individually at 9%. Specific mechanical energy (SME) input decreased as die temperature for each vegetable addition increased. All extrudates decreased in density and breaking strength, but increased in specific length and water soluble index as $CO_2$ gas injection increased. Elastic modulus decreased as the die temperature and $CO_2$ gas injection increased. Extruded green tea mix with $CO_2$ gas injection at 150 mL/min was larger pore size and higher amount of pore than the tomato and pumpkin extrudates with $CO_2$ gas injection. Cold extrusion with $CO_2$ gas injection at $60^{\circ}C$ die temperature could be applicable for making Saengsik (uncooked food).

• Research in Community and Public Health Nursing
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• v.5 no.2
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• pp.109-129
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• 1994

Chronic health problems has become a major concern and challenge to the health care professionals today. Especially hypertension, one of the leading primary cause of death in Korea, is a typical chronic disease requiring adequate and continuous management. Though these hypertensives need to maintain desirable health practice by themselves for their life time, many previous studies indicated that most of the essential hypertensives have no specific symptoms and thus, reluctant to follow appropriate medical regimens causing the condition further aggravated and complicated. Self-care is an essential factor that keeps chronic patients in control of their health and wellness. Thus this study was conducted to identify the effect of the comprehensive self-regulation program as a nursing intervention on the promotion self-care performance and improvement in physical parameters of hypertensives. For this purpose, a one group quasi-experimental research with pre and post test design was used. The subjects of the study was consisted of thirty persons with mild or moderate essential hypertension from two companies in Cheong-ju city. The whole program was carried out from October, 1993 to February, 1994. The self-regulation program was consisted with group education on hypertension and self-care, self-regulation including the blood pressure self-monitoring and recording, recording of daily self-care activities, and encouraging and reinforcing self-efficacy through verbal persuation and enactive attainment. The subjects were asked to measure their own blood pressure by themselves twice per day and to record blood pressure and the daily self-care performance according to the instructions provided during the whole period of 9 weeks. The instruments used for data collection in this study were as follows : 1) Instruments used for measuring the knowledge about hypertension, multiple health locus of control, and perceived benifits and barriers were adapted from previous studies and modified by author to be fit for the subjects. 2) Self-efficacy scale and self-care performance record were developed by the author. 3) Physiological parameters included systolic / diastolic blood pressure, body weight, level of blood cholesterol, and 24hour ambulatory blood pressure. The post-experimental Cronbach's Alpha as the reliability test of scales were 0.703-0.897, an appropriate level of confidence. The effect of the program was analyzed by experimental stages ; the first week, the fifth week, and the ninth week since the experimental imput began. Data were analyzed by the SPSS PC+ program with paired t-test and t-test, repeated measure ANOVA, and pearson's correlation to de termine the effect of program. The results were as follows : 1) After the self-regulation program, scores on knowledge(t=-2.41, p=.011), perceived self-efficacy (F=5.60, p=.001), self-care performance(F=22.31, p=.0001) were significantly higher than those before the program. 2) After the program, both systolic and diastolic blood pressure were significantly lower than those before the program(F=10.89 -13.11, p=.0001). However in 24hour ambulatory blood pressure, systolic mean pressure was nearly significantly lower, but not in diastolic mean pressure. 3) After the program, the body weight was significant decresed(t=5.53, p=.0001), but the blood cholesterol level was not decreased significantly except in those cases with higher cholesterol level. 4) There were significant relationships between changes in self-care performance and diastolic pressure at 1st week (r=.3389, p=.033) and changes in self-care performance and systolic pressure at 9th week(r=.3651, p=.024). 5) There were significant relationship between perceived self-efficacy and self-care performance at 5th week(r=.5313, p=.001) and 9th week (r=.3026, p=.052). 6) After the program, internal health locus of control and perceived benefits did not show significant change, but perceived barriers was significantly lower than those before the program (t=3.57, p=.0001). From the above results, it can be concluded that 1) The self-regulation program is an effective nursing strategy to promote self-care performance of hypertensives and to lower the blood pressure. Thus this program can be recommended in the management of the hypertensives in workplaces and community settings. 2) The synthesis of Orem's self-care theory and Bandura's self-regulation & self-efficacy theory in this study was proved to enhance explanation and prediction of the change of self-care behavior. Thus the result of the study would contribute in development of the self-care theory and an expansion of practice-theory.

• Journal of Nutrition and Health
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• v.42 no.4
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• pp.386-396
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• 2009

The purpose of this study was to analyze the effect of push, pull and push-pull interactive factors for CFMC (Contract Foodservice Management Company)'s internationalization. The study was a quantitative study part in mixed methods (QUAL ${\rightarrow}$ quan) which was mainly qualitative study and quantitative study. Mail survey was carried out for quantitative study. For study subjects, 1,281 persons who completed 'Food Service Management Professional Program' of 'Y' University were selected as a population because the program was mainly for CFMC's workers. The analysis methods used in this study were frequency analysis, factor analysis, correlation analysis and multiple regression analysis with SPSS 17.0. Push factors had the saturation in domestic market and the manager's purpose (fac.1) and the investment for internationalization (fac.2). Pull factors had the company's external environment for internationalization (fac.3) and the global network and spread of culture (fac.4). Push-pull interactive factors had the information about foreign market (fac.5), the procedure and budget of overseas expansion (fac.6) and the national network and size of domestic market (fac.7). Internal dynamics factors had the deterrents for internationalization (fac.8) and the enablers for internationalization (fac.9). The result showed that the company's external environment in pull factors had positive effects on the deterrents for internationalization. The global network and the spread of culture had positive effects on the enablers for internationalization. The information about foreign market in push-pull interactive factors had positive effects on the deterrents and enablers for internationalization. The national network and the size of domestic market had positive effects on the enablers for internationalization. The deterrents and enablers for internationalization had positive effects on the level of internationalization, and the deterrents had more effects on the level of internationalization than the enablers did (${\beta}$= .492 > .177).

• Journal of Distribution Research
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• v.17 no.1
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• pp.65-86
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• 2012

The $20^{th}$ century was the era of manufacturer brands which built higher brand equity for consumers. Consumers moved from generic products of inconsistent quality produced by local factories in the $19^{th}$ century to branded products from global manufacturers and manufacturer brands reached consumers through distributors and retailers. Retailers were relatively small compared to their largest suppliers. However, sometime in the 1970s, things began to slowly change as retailers started to develop their own national chains and began international expansion, and consolidation of the retail industry from mom-and-pop stores to global players was well under way (Kumar and Steenkamp 2007, p.2) In South Korea, since the middle of the 1990s, the bulking up of retailers that started then has changed the balance of power between manufacturers and retailers. Retailer private labels, generally referred to as own labels, store brands, distributors own private-label, home brand or own label brand have also been performing strongly in every single local market (Bushman 1993; De Wulf et al. 2005). Private labels now account for one out of every five items sold every day in U.S. supermarkets, drug chains, and mass merchandisers (Kumar and Steenkamp 2007), and the market share in Western Europe is even larger (Euromonitor 2007). In the UK, grocery market share of private labels grew from 39% of sales in 2008 to 41% in 2010 (Marian 2010). Planet Retail (2007, p.1) recently concluded that "[PLs] are set for accelerated growth, with the majority of the world's leading grocers increasing their own label penetration." Private labels have gained wide attention both in the academic literature and popular business press and there is a glowing academic research to the perspective of manufacturers and retailers. Empirical research on private labels has mainly studies the factors explaining private labels market shares across product categories and/or retail chains (Dahr and Hoch 1997; Hoch and Banerji, 1993), factors influencing the private labels proneness of consumers (Baltas and Doyle 1998; Burton et al. 1998; Richardson et al. 1996) and factors how to react brand manufacturers towards PLs (Dunne and Narasimhan 1999; Hoch 1996; Quelch and Harding 1996; Verhoef et al. 2000). Nevertheless, empirical research on factors influencing the production in terms of a manufacturer-retailer is rather anecdotal than theory-based. The objective of this paper is to bridge the gap in these two types of research and explore the factors which influence on manufacturer's private label production based on two competing theories: S-C-P (Structure - Conduct - Performance) paradigm and resource-based theory. In order to do so, the authors used in-depth interview with marketing managers, reviewed retail press and research and presents the conceptual framework that integrates the major determinants of private labels production. From a manufacturer's perspective, supplying private labels often starts on a strategic basis. When a manufacturer engages in private labels, the manufacturer does not have to spend on advertising, retailer promotions or maintain a dedicated sales force. Moreover, if a manufacturer has weak marketing capabilities, the manufacturer can make use of retailer's marketing capability to produce private labels and lessen its marketing cost and increases its profit margin. Figure 1. is the theoretical framework based on a strategic market management perspective, integrated concept of both S-C-P paradigm and resource-based theory. The model includes one mediate variable, marketing capabilities, and the other moderate variable, competitive intensity. Manufacturer's national brand reputation, firm's marketing investment, and product portfolio, which are hypothesized to positively affected manufacturer's marketing capabilities. Then, marketing capabilities has negatively effected on private label production. Moderating effects of competitive intensity are hypothesized on the relationship between marketing capabilities and private label production. To verify the proposed research model and hypotheses, data were collected from 192 manufacturers (212 responses) who are producing private labels in South Korea. Cronbach's alpha test, explanatory / comfirmatory factor analysis, and correlation analysis were employed to validate hypotheses. The following results were drawing using structural equation modeling and all hypotheses are supported. Findings indicate that manufacturer's private label production is strongly related to its marketing capabilities. Consumer marketing capabilities, in turn, is directly connected with the 3 strategic factors (e.g., marketing investment, manufacturer's national brand reputation, and product portfolio). It is moderated by competitive intensity between marketing capabilities and private label production. In conclusion, this research may be the first study to investigate the reasons manufacturers engage in private labels based on two competing theoretic views, S-C-P paradigm and resource-based theory. The private label phenomenon has received growing attention by marketing scholars. In many industries, private labels represent formidable competition to manufacturer brands and manufacturers have a dilemma with selling to as well as competing with their retailers. The current study suggests key factors when manufacturers consider engaging in private label production.