• Journal of the Korean Academy of Child and Adolescent Psychiatry
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• v.8 no.1
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• pp.22-33
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• 1997

The objective of this study is to understand disordered parent-child relationships of Reactive Attachment Disorder(RAD) systematically through the mother’ internal working model of child. In this study, RAD mothers’internal representations of the child were compared with mothers’of control group and association between mothers’ representation classifications and children’ attachment classifications was examined. Also individual differences in mother-child interaction by mothers’representation classifications was observed. The subjects of this study were 40 2-5 year-old children and their mothers, 20 attachment disordered dyads and 20 normal dyads of control group. Mothers were interviewed using the Working Model of the Child(Zeanah, Benoit & Barton 1986) to classify internal representations of child. Children’ attachment patterns were assessed by the Strange Situation Procedure. For observation of motherchild interaction, Each dyad was seen in DPICS devised by Eyberg and Robinson(1983). The results of the study were as follows：1) Among RAD group, 55% of mothers were classified as disengaged and 45% classified as distorted, while all mothers of control group were classified as balanced. In rating scales, there were significant differences in all 3 representation classifications in Intensity of involvement and Coherence. In Intensity of involvement disengaged representations had the lowest score and distorted representations had the lowest score in Coherence. 2) Mothers’representation classifications were related to children’ attachment classifications. All mothers of control group whose children were classified as secure were classified as balanced. Among RAD’ mothers, by contrast, 82% of mothers classified as disengaged had children classified as anxious-avoidant, 56% of mothers classified as distorted had children classified as disorganized / disoriented and 33% of mothers classified as distorted had children classified as anxious-resistant. 3) There were individual differences in mother-child interactions by mothers’representation classifications. In the child-centered play, mothers classified as disengaged used discriptive statement, reflective statement and discriptive-reflective question less than balanced mothers. Mothers classified as distorted used direct command and indirect command more than balanced mothers. In the clean-up task, mothers classified as disengaged and distorted used direct command and indirect command more than balanced mothers. The results of this study suggest that parents’working model of the child is an important factor to understand parent-child attachment relationships and their interactions. The understanding of parents’ working model of the child is thought to enrich our understanding of disordered parent-child relationships and to provide useful informations for specific and successful treatments.

• Asia pacific journal of information systems
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• v.19 no.3
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• pp.69-98
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• 2009

We investigated what factors motivate gamers to participate in a guild and why they continue to be engaged as members of the guild. We find that, based on the result of focus group interviews with MMORPG gamers, social support and self-esteem factors play important roles. Considering both prior research and the focus group interviews we have conducted, we define social support and character control as independent variables. Character identity, guild identity, and self-esteem are proposed as mediating variables while guild flow and game loyalty as dependent variables. Accordingly, we develop the research model and hypotheses, and verify them empirically. Based on our experiences of playing the WoW game, we proposed a research model and conducted focus-group interviews (FGIs). FGIs involve formulating a hypothesis and then collecting some relevant data. FGIs were conducted face-to-face with students of C University in Korea. We formulated structured interview schedules, and the questions were based on our research variables and personal experiences. The questions for the interviews encompassed the following areas: (a) the demographic characteristics of the focus group; (b) the number of years for which respondents had played online games; (c) the motive for starting a game; (d) the number of game-characters assumed by each gamer; (e) the type of game played; and (f) other issues such as the reasons for involvement in the play, the willingness to reuse the game in case new versions were released, etc. On average, it took two hours to interview each of three groups. A primary set of FGIs was conducted with three groups on the premise that there would be some differences caused by character race (Horde vs. Alliance) or by playable server (Normal vs. Combat). With respect to the manner of playing, we found that guild members shared information, felt a sense of belonging, and played computer games for quite a long time through the guild; however, they did not undergo these experiences when playing alone. Gamers who belonged to a specific guild helped other players without expecting compensation for that, freely shared information about the game, gave away items for free, and more generous with other members who made mistakes. The guild members were aware of the existence other members and experienced a sense of belonging through interactions with, and evaluations from, other players. It was clear that social support was shown within the guild and that it played an important role as a major research variable. Based on the results of the first FGIs, a second set of in-depth FGIs was carried out with a focus on the psychology of the individual within the guild and the social community of the guild. The second set of FGIs also focused on the guild's offline meetings. Gamers, over all, recognize the necessity of joining a community, not only off-line but also online world of the guild. They admit that the guild is important for them to easily and conveniently enjoy playing online computer games. The active behavior and positive attitudes of existing guild members can motivate new members of the guild to adapt themselves to the guild environment. They then adopt the same behaviors and attitudes of established guild members. In this manner, the new members of the guild strengthen the bonds with other gamers while feeling a sense of belonging, and developing social identity, thereby. It was discovered that the interaction among guild members and the social support encouraged new gamers to quickly develop a sense of social identity and increase their self-esteem. The guild seemed to play the role of socializing gamers. Sometimes, even in the real world, the guild members helped one another; therefore, the features of the guild also spilled over to the offline environment. We intend to use self-esteem, which was found through the second set of FGIs, as an important research variable. To collect data, an online survey was designed with a questionnaire to be completed by WoW gamers, who belong to a guild. The survey was registered on the best three domestic game-sites: 'WoW playforum,' 'WoW gamemeca,' and 'Wow invent.' The selected items to be measured in the questionnaire were decided based on prior research and data from FGIs. To verify the content of the questionnaire, we carried out a pilot test with the same participants to point out ambiguous questions as a way to ensure maximum accuracy of the survey result. A total of 244 responses were analyzed from the 250 completed questionnaires. The SEM analysis was used to test goodness-of-fit of the model. As a result, we found important results as follows: First, according to the statistics, social support had statistically significant impacts on character control, character identity, guild identity and self-esteem. Second, character control had significant effects on character identity, guild identity and self-esteem. Third, character identity shows its clear impact on self-esteem and game loyalty. Fourth, guild identity affected self-esteem, guild flow and game loyalty. Fifth, self-esteem had a positive influence on the guild flow. These days, the number of virtual community is rising along with its significance largely because of the nature of the online games. Accordingly, this study is designed to clarify the psychological relationship between gamers within the guild that has been generally established by gamers to play online games together. This study focuses on the relationships in which social support influences guild flow or game loyalty through character control, character identity, guild identity, and self-esteem, which are present within a guild in the MMORPG game environment. The study results are as follows. First, the effects of social support on character control, character identity, guild identity and self-esteem are proven to be statistically significant. It was found that character control improves character identity, guild identity and self-esteem. Among the seven variables, social support, which is derived from FGIs, plays an important role in this study. With the active support of other guild members, gamers can improve their ability to develop good characters and to control them. Second, character identity has a positive effect on self-esteem and game loyalty, while guild identity has a significant effect on self-esteem, guild flow and game loyalty. Self-esteem affects guild flow. It was found that the higher the character and guild identities become, the greater the self-esteem is established. Contrary to the findings of prior research, our study results indicate that the relationship between character identity and guild flow is not significant. Rather, it was found that character identity directly affects game players' loyalty. Even though the character identity had no direct effect on increasing guild flow, it has indirectly affected guild flow through self-esteem. The significant relationship between self-esteem and guild flow indicates that gamers achieve flow, i.e., a feeling of pleasure and excitement through social support. Several important implications of this study should be noted. First, both qualitative and quantitative methods were used to conduct this study. Through FGIs, it was observed that both social support and self-esteem are important variables. Second, because guilds had been rarely studied, this research is expected to play an important role in the online community. Third, according to the result, six hypotheses (H1, H5, H6, H7, H8, and H11) setup based on FGIs, were statistically significant; thus, we can suggest the corresponding relationships among the variables as a guideline for follow-up research. Our research is significant as it has following implications: first, the social support of the guild members is important when establishing character control, character identity, guildidentity and self-esteem. It is also a major variable that affects guild flow and game loyalty. Second, character control when improved by social support shows notable influence on the development of character identity, guild identity and self-esteem. Third, character identity and guild identity are major factors to help establish gamers' own self-esteem. Fourth, character identity affects guild flow through self-esteem and game loyalty. The gamers usually express themselves through characters; the higher character identity is, the more loyalty a gamer has. Fifth, guild identity, established within the guild, has clear effects on self-esteem, guild flow and game loyalty. Sixth, qualitative and quantitative methods are employed to conduct this study. Based on the results of focus group interviews and SEM analysis, we find that the social support by guild members and psychological factors are significant in strengthening the flow of guild and loyalty to the game. As such, game developers should provide some extra functions for guild community, through which gamers can play online games in collaboration with one another. Also, we suggest that positive self-esteem which is built up through social support can help gamers achieve higher level of flow and satisfaction, which will consequently contribute to minimizing the possibility for the players to develop negative attitude toward the guild they belong to.

• Maxillofacial Plastic and Reconstructive Surgery
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• v.30 no.3
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• pp.217-224
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• 2008

Angiogenesis plays an important role in bone development and postnatal bone fracture repair. Vascular endothelial growth factor (VEGF) and vascular endothelial growth factor receptors (VEGFRs) have been thought to be primarily involved in promoting angiogenesis. It is well known that VEGF and its receptors have been reported to play an important role in the regulation of the interaction between angiogenesis and osteogenesis during bone repair processes. Dexamethasone, a potent synthetic glucocorticoid, promotes phenotype markers of osteoblast differentiation, such as ALP and osteocalcin. It stimulates in vitro osteogenesis of human bone marrow osteogenic stromal cells. Dexamethasone has been reported to suppress VEGF gene expression in some cells. However, our previous study demonstrated VEGF quantification increased in a time-dependent manner in periosteal-derived osteogenesis under dexamethasone. So, the purpose of this study was to examine the angiogenic phenotypes in cultured human periosteal-derived cells under high-dose dexamethasone. Periosteal-derived cells were cultured using a technique previously described. After passage 3, the periosteal-derived cells were further cultured for 28 days in an osteogenic inductive culture medium containing ascorbic acid, ${\beta}$-glycerophosphate and high-dose dexamethasone, We evaluated the expression of VEGF isoforms, VEGFR-1, VEGFR-2, and neuropilin-1, ALL VEGF isoforms ($VEGF_{121},\;VEGF_{165},\;VEGF_{189}$, and $VEGF_{206}$) expression was observed by RT-PCR analysis. VEGFR-1, VEGFR-2 and neuropilin-1 expression increased up to day 14, particularly during the early stage of mineralization. Our results suggest the involvement of direct VEGFs/VEGFRs system on periosteal-derived cells during early mineralization phase under high-dose of dexamethasone. These also suggest that VEGF might act as an autocrine growth molecule during osteoblastic differentiation of cultured human periosteal-derived cells.

• Journal of the Korean Association of Oral and Maxillofacial Surgeons
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• v.34 no.3
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• pp.245-249
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• 2008

Epidermal growth factor is a single-chain polypeptide consisting of 53 amino acids and has a potent mitogenic activity that stimulates proliferation of various normal and neoplastic cells through the interaction with its specific receptor(epidermal growth factor receptor, EGFR). Pleomorphic adenoma is the most common salivary benign tumor and histologically, it contains the epithelial cell, the myo-epithelial cell and mesenchymal ingredient, which is various aspect. Adenoid cystic carcinoma is an infiltrative malignant salivary gland tumor with three different histological patterns: cribriform, tubular or solid. The tumor cell structure composed of modified myoepithelial cell, and basaloid cell. In this study, we used an immunohistochemical technique to investigate the expression of EGF in 6 specimens of adenoid cystic carcinoma and 10 specimens of pleomorphic adenoma taken from patients treated at Dept. of Oral and Maxillofacial Surgery, Dankook University. The results were as follows. 1. In pleomorphic adenoma, ductal structure and scattered spindle cells in hyalinized stroma, disclosing myxoid stroma and hyalin, cartilage formation were observed. Immunohistologically, weak EGF expression in ductal structure and negative in stromal area were observed. 2. Cribriform type of adenoid cystic carcinoma showed numerous pseudocyst surrounded by dark small neoplastic cells in the back-ground of fibrous connective tissue and moderate EGF expression of dark cells adjacent to pseudo lumen in cribriform pattern, while weak expression in other most cells. 3. Tubular type of adenoid cystic carcinoma showed numerous ductal pattern surrounded by two layered neoplastic cells in the back-ground of fibrous connective tissue and strong EGF expression in luminal cells of ductal structure, while weak expression in outer cells. From the results obtained, we suggest that EGF is mainly biosynthesized in cells forming duct like structures of tubulo-ductal type or cribriform adenoid cystic carcinoma and it may play a role, as a cell mitogen in adenoid cystic carcinoma growth.

• Korean Journal of Ecology and Environment
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• v.36 no.4 s.105
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• pp.391-402
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• 2003

Last 20 years have witnessed many studies dealing with effects of elevated $CO_2$ on terrestrial ecosystems. However, fewer efforts have been made to elucidate effects on wetland ecosystems, although they play a key role in global biogeochemical cycles. This review synthesizes published data to reveal effects of elevated $CO_2$ on wetland plants. In particular, we focused on the changes in primary production, community structures, evapotranspiration, and nutrients in plants. Many studies have reported increases in primary production in individual plants, but we could not conclude that this will lead to increases in carbon sequestration in wetland ecosystems. The reasons include transport of photosynthates into belowground parts, speciesspecific responses, interaction among different species, and limitation of other nutrients. However, elevated $CO_2$ increased transpiration rates in many wetland plants, suggesting substantial influences on water budgets of wetlands. In addition, similar to terrestrial ecosystems, elevated $CO_2$ increased C/N ratio of many plants, which may impede organic matter decomposition in the long term. However, further information on dynamics of belowground carbon supplied from wetland plants is warranted to assess effects of elevated $CO_2$ on wetland carbon cycle accurately.

• Safety and Health at Work
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• v.4 no.1
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• pp.52-62
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• 2013

Objectives: To investigate the association between psychological distress and obesity among law enforcement officers (LEOs) in the United States. Methods: Self-reported data on psychological distress based on six key questions were obtained from LEOs who participated in the National Health Interview Survey (2004-2010). We used Prochaska's cut-point of a Kessler 6 score ${\geq}5$ for moderate/high mental distress in our analysis. Mean levels of body mass index (BMI) were compared across three levels of psychological distress. Results: The average age of LEOs (n = 929) was 39.3 years; 25% were female. Overall, 8.1% of LEOs had moderate or high psychological distress; 37.5% were obese (BMI ${\geq}30$). Mean BMI increased with increasing psychological distress (no distress, BMI = $27.2kg/m^2$; mild distress, $27.6kg/m^2$; and moderate/high distress, $33.1kg/m^2$; p = 0.016) after adjustment for age, race, income, and education level among female officers only. Physical activity modified the association between psychological distress and BMI but only among male LEOs (interaction p = 0.002). Among male LEOs reporting low physical activity, psychological distress was positively associated with BMI ($30.3kg/m^2$ for no distress, 30.7 for mild distress, 31.8 for moderate/high distress; p = 0.179) after adjustment, but not significantly. This association was not significant among males reporting high physical activity. Conclusion: Mean BMI significantly increased as psychological distress increased among female LEOs. A longitudinal study design may reveal the directionality of this association as well as the potential role that physical activity might play in this association.

• Smart Media Journal
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• v.3 no.3
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• pp.36-45
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• 2014

Based on the perception of Maurice Merleau Ponty, This study defines that Moving is a form lively to experience meaning, pleasure as the aesthetic attribute structured to a product, expression and value are synthesized into. The purpose of study is to argue that Wearable, Ubiquitous, Interaction, Play, D, I, Y, Universal, Ecology are the forms, modalities that the moving is variously subjected to the product design. Above This is the result reasoned according to analogical form as below between the moving and all design forms. First, The moving as the aesthetic expression and value are synthesized into is the intrinsic, general proposition, maxim for the value judgement. Second, All design forms are the cases which the values based on the aesthetic expression system are subjected to Third, Thus All design forms are the modalities of the aesthetic expression based on the values. The certainty of this judgement, reasoning is the proof that the correspondence between the moving as the aesthetic expression and design form is the fact. That is to say, It is the proof that Users lively experience the aesthetic meaning, pleasure in fact as the aesthetic values are subjected to all design forms. The lived experience of each user in their daily life itself is the only method or assurance for this. The moving integrates the existence of a product and what should be of users into the aesthetic dimension and at the same time, is realized based on this. The emphasized theme in all cases of this study is not the product but the moving. So, The product design is changed into the action which structures the moving like above to a product.

• 한국HCI학회:학술대회논문집
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• 2006.02a
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• pp.945-953
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• 2006

The researchers in the field of cognitive science and learning science suggest that the teaching activity induces the elaborative and meaningful learning. Actually, lots of research findings have shown the beneficial effect of learning by teaching such as peer tutoring. But peer tutoring has some limitations in the practical learning context. To overcome some limitations, the new concept of "learning by teaching" through the agent called Teachable Agent. The teachable agent is a modified version of traditional intelligent tutoring system that assigns a role of tutor to teach the agent. The teachable agent monitors individual difference and provides a student with a chance for deep learning and motivation to learn by allowing them to play an active role in the process of learning. That is, The teaching activity induces the elaborative and meaningful learning. This study compared the effects of our teachable agent, KORI, and peer tutoring on the cognition and motivation. The field experiment was conducted to examine whether learning by teaching the teachable agent would be more effective than peer tutoring and reading condition. In the experiment, all participants took 30 minutes lesson on rock and rock cycle together to acquire the base knowledge in the domain. After the lesson, participants were randomly assigned to one of the three experimental conditions; reading condition, peer tutoring condition, and teachable agent condition. Next, participants of each condition moved into separated place and performed their own learning activity. After finishing all of the learning activities in each condition, all participants were instructed to rate the interestingness using a 5-point scale on their own learning activity and leaning material, and were given the comprehension test. The results indicated that the teachable agent condition and the peer tutoring condition showed more interests in the learning than the reading condition. It is suggested that teachable agent has more advantages in overcoming the several practical limitations of peer tutoring such as restrictions in time and place, tutor's cognitive burden, unnecessary interaction during peer tutoring. The applicability and prospects of the teachable agent as an efficient substitute for peer tutoring and traditional intelligent tutoring system were also discussed.

• Journal of Life Science
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• v.30 no.9
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• pp.826-833
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• 2020

Phospholipase C gamma (PLCγ) has critical roles in receptor tyrosine kinase- and non-receptor tyrosine kinase-mediated cellular signaling relating to the hydrolysis of phosphatidylinositol 4,5-bisphosphate [PI(4,5)P₂] to produce inositol 1,4,5 trisphosphate (IP₃) and diacylglycerol (DAG), which promote protein kinase C (PKC) and Ca²⁺ signaling to their downstream cellular targets. PLCγ has two isozymes called PLCγ1 and PLCγ2, which control cell growth and differentiation. In addition to catalytically active X- and Y-domains, both isotypes contain two Src homology 2 (SH2) domains and an SH3 domain for protein-protein interaction when the cells are activated by ligand stimulation. PLCγ also contains two pleckstrin homology (PH) domains for membrane-associated phosphoinositide binding and protein-protein interactions. While PLCγ1 is widely expressed and appears to regulate intracellular signaling in many tissues, PLCγ2 expression is restricted to cells of hematopoietic systems and seems to play a role in the regulation of immune response. A distinct mechanism for PLCγ activation is linked to an increase in phosphorylation of specific tyrosine residue, Y783. Recent studies have demonstrated that PLCγ mutations are closely related to cancer, immune disease, and brain disorders. Our review focused on the physiological roles of PLCγ by means of its structure and enzyme activity and the pathological functions of PLCγ via mutational analysis obtained from various human diseases and PLCγ knockout mice.

• Journal of the Korean Association of Geographic Information Studies
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• v.21 no.2
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• pp.94-106
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• 2018

The epidemiological model is useful for creating simulation and associated preventive measures for disease spread, and provides a detailed understanding of the spread of disease space through contact with individuals. In this study, propose an agent-based spatial model(ABM) integrated with spatial big data to simulate the spread of MERS-CoV infections in real time as a result of the interaction between individuals in space. The model described direct contact between individuals and hospitals, taking into account three factors : population, time, and space. The dynamic relationship of the population was based on the MERS-CoV case in Seoul Metropolitan Government in 2015. The model was used to predict the occurrence of MERS, compare the actual spread of MERS with the results of this model by time series, and verify the validity of the model by applying various scenarios. Testing various preventive measures using the measures proposed to select a quarantine strategy in the event of MERS-CoV outbreaks is expected to play an important role in controlling the spread of MERS-CoV.