• Journal of the korean academy of Pediatric Dentistry
• /
• v.34 no.2
• /
• pp.183-191
• /
• 2007

Through out the world dental caries seems to be decreased as it is difficult to make an accurate diagnosis for dental caries. The traditional diagnostic method which is probing and x-ray taking has many limitations to diagnose the early caries, so there were recommendations for the needs of new equipments such as laser fluorescence(LF), digital imaging fiber-optic trans-illumination(DIFOTI), and quantitative light fluorescence (QLF) which were developed from various study results. Also confocal laser scanning microscopy(CLSM) and ultrasonics are used for research progression. This study is to evaluate whether it is possible to monitor accurately for remineralization amount of enamel surface early caries using DIFOTI or LF After inducing artificial caries to bovine teeth to 10 participants remineralization was enhanced by 0 ppm and 500 ppm fluoride mouth rinse solution for 3 weeks. Then they were cross sectioned and analyzed using gold standard of the lesion depth measured by CLSM. The following results were obtained: 1. The measured percentage of light intensity(luminosity ratio) by DIFOTI increased with remineralization period, and showed significant reverse correlation with lesion depth measured by CLSM (p<0.01). 2. The measurement of laser fluorescence increased with remineralization period, and showed significant correlation with lesion depth measured by CLSM (p<0.01). 3. To the result for CLSM, 500 ppm fluoride mouth rinse group showed rapid rate for decreased tendency of lesion depth than 0 ppm fluoride mouth rinse group. In conclusion DIFOTI system was used to measure accurately for the remineralization amount of early surface caries, it is a very useful equipment to detect precisely the changes for early enamel caries remineralization during treatments.

• Journal of the korean academy of Pediatric Dentistry
• /
• v.44 no.3
• /
• pp.358-364
• /
• 2017

For the purpose of convenience and reducing time, newer bonding agents have been developed for composite resin restoration. Recently developed one bottle bonding system including etching, primer and adhesive can make procedures simpler and less technique-sensitive than old generation adhesives. The aim of this study was comparing the shear bond strength of new dentin bonding agents to the 5th generation bonding agent which had an etching step. 78 premolar teeth were randomly divided into three groups which were treated with $Tetric^{(R)}$ N-Bond Universal (Ivoclar Vivadent, Liechtenstein), $GC^{(R)}$ G-Premio BOND (GC Co., Japan) without additional etching step and $3M^{TM}$ Single Bond2 (3M ESPE, USA) with an etching step following manufacturer's instructions. $Filtek^{TM}$ Z-350 (3M ESPE, USA) composite resin was applied and light cured over bonding agents. For shear bond strength evaluation, universal testing machine was used with a wedge technique. As a result, shear bond strength of one step bonding agents was lower than two step bonding agent and there were statistically significant differences between them (p < 0.05). In addition, within the result of two new bonding agents, $Tetric^{(R)}$ N-Bond Universal showed significantly higher shear bond strength than $GC^{(R)}$ G-Premio BOND (p < 0.05).

• The Korean Journal of Elementary Counseling
• /
• v.8 no.1
• /
• pp.51-66
• /
• 2009

This study aims at examining how it becomes to change the interpersonal cognitive problem solving ability development of elementary rejected children when teacher practices counseling strategy in classroom To do this, 130 fifth-graders of 4 classrooms from H Elementary School in B City went through Ahn Ie-hwan's(2007) social status type system by using the peer nomination, Then, 21 children were labeled as rejected children. Among them, 16 children were divided into experimental group & control group, 8 for the each group. In order to improve the interpersonal cognitive problem solving ability of rejected children with teacher's counseling strategy in classroom used in this study, 5 weeks activity made according to the level of classroom was carried out in four sides, that is, setting of classroom structure-environments, classroom activities, counseling activities, cooperative learning method, referring to Dreikurs'(1971) 'The counseling strategy in classroom' composed of self-discipline, cooperation, mutual respect, shared responsibility, and social equality. This study obtained the following results. First, There was a significant effect in improving the interpersonal cognitive problem solving ability of rejected children. Looking into sub-factors, there was a significant effect in improving consequential thought and method-ends thought except alternative solution thought and causal thought. Second, there was a significant difference in social status & change of 5 types of children in social status in the respective classrooms when those of the experimental group where teacher's counseling strategy in classroom carried out and those of the control group where teacher's counseling strategy in classroom not carried out were compared. To conclude the results mentioned above, We can see the fact that the counseling strategy in classroom positively affected interpersonal cognitive problem solving ability.

• Korean Journal of Biological Psychiatry
• /
• v.15 no.1
• /
• pp.14-22
• /
• 2008

Objectives : The authors purposed to present data for explaining gene-environmental interaction causing depressive disorder by examining the effects of genetic factors related to the serotonin system and environmental factors such as stressful life events in early adulthood. Methods : The subjects were 150 young adults(mean age 25.0${\pm}$0.54), a part of 534 freshmen who had completed the previous study of genotyping of TPH1 gene. We assessed characteristics of life events, depression and anxiety scale and checked if they had a depressive disorder with DSM-IV SCID interview. Along with TPH1 A218C genotype confirmed in previous study, TPH2 -1463G/A and 5HTR2A -1438A/G genes were genotyped using the SNaPshot$^{TM}$ method. Results : In comparison with the group without C allele of TPH1 gene, the number of life events had a significant effect on the probability of depressive disorder in the group with C allele. Other alleles or genotypes did not have a significant effect on the causality of life events and depressive disorder. Conclusion : The results of this study suggest that TPH1 C allele is a significant predictor of onset of depressive disorder following environmental stress. It means that the TPH1 gene may affect the gene-environmental interaction of depressive disorder.

• The Mathematical Education
• /
• v.58 no.4
• /
• pp.567-588
• /
• 2019

This study is a follow-up to Lee(2019). Lee(2019) investigated the method of collecting information on the curriculum of elementary and middle school math teachers, when differences were observed between elementary and middle school math teachers in the method of collecting information on the curriculum. Following Lee(2019)'s study, this study looked at the perceptions and experiences of high school math teachers in their curriculum.At the time when the curriculum was changed from time to time, the authority for restructuring curriculum was strengthened. In addition, the role of teachers as 'curriculum restructuring practitioners' became important. However, previous studies have pointed out the structural problem that teachers empathize with the necessity of restructuring the curriculum and have a negative perception of the willingness to practice the curriculum. Therefore, the researcher examined high school teachers who are sensitive to the characteristics and evaluation of the highly hierarchical mathematics subjects. A total of six interviews were conducted with ten high school mathematics teachers in three groups of ten years of teaching experience. Through this, it was possible to observe how teachers as curriculum reconstruction practitioners had thought about curriculum restructuring, and I could observe what difficulties teachers' experienced. This suggests that teachers have two ideas for restructuring the curriculum: 'realistic curriculum reconstruction' and 'ideal curriculum reconstruction'. In addition, the teachers found that there are 'sides of incongruity in the school system' and 'difficulties in the management of teachers'.

• Asia pacific journal of information systems
• /
• v.18 no.2
• /
• pp.73-94
• /
• 2008

When individuals collaborated in virtual settings, communication is medicated through a variety of communication technologies, and is associated not only with communication effectiveness but also with socio-emotional interactions among group members. In this regards, scholars have examined how technology-mediated communication systems can be designed and used to facilitated communication interaction. However, the empirical results of the previous studies have revealed inconsistencies in the effects of communication media on users' behavioral or attitudinal responses, and on their viable effectiveness in organizations. Some studies claim that computer-mediated communication(CMC) is task-oriented but not suitable for emotional expression since it hinders close interpersonal interaction. On the other hand, some studies argue that individuals are able to develop interpersonal relationships more effectively in a CMC environment than in an FtF-environment. Due to the different perspectives, a theoretical gap exists, and it leads to the inconsistent research findings. The purpose of this paper is to combine the two different perspectives into single unified model, thereby providing a more realistic and comprehensive understanding about virtual collaboration. The present study here sought to answers the following questions with organizational communication perspective: What are the major components of virtual collaboration? What factors affect the performance of virtual collaboration? And what kind of managerial efforts should organization make in order to facilitate CMC media effectiveness in virtual collaboration? Although there is a certain belief that new media, namely technology-mediated communication support would create new opportunities, the problem of "how" or "why" has been an important question that is still not fully addressed. In this regards, we collectively reexamined previous literatures with major issues which are still controversial and integrated various theoretical activity within computer-mediated communication domain: task-oriented approach, socio-emotional approach, and evolutionary psychological approach. Our first contribution is to develop a framework for virtual collaboration by combining two different perspectives into a single unified model, providing a more realistic and comprehensive understanding. The second main contribution is the joint modeling of both social presence and cognitive effort, and the effects on two distinct but important communication outcomes(i.e., take performance and relational development). We tested the research hypotheses which were developed based on the various CMC theories using data gathered through a self-administered mail survey of 127 individuals of 69 virtual workgroups. The proposed model was supported, providing preliminary evidence that the tension between two opposite view should be integrated. The results show that the individual's psychological processes(social presence and cognitive effort) in a virtual environment significantly mediated the effect of CMC inputs (media richness, user adaptation, and shared contest) on the CMC outputs (task performance and relational development). Furthermore, this study shows that the lack of perceived media richness of CMC media can be complemented by user adaptation and shared context. Based on the results, we discuss how communication system should be designed and implemented so as to promote virtual interaction as well as how a virtual workgroup should be composed to complement the lack of media richness. A virtual collaboration using CMC media may create new value by overcoming the logistical constraints. On the other hand, it may also generate various managerial risks such as communicational depersonalization, process dissatisfaction, and low cohesion. Therefore, this study suggests that organization managers should carefully choose the CMC mediums and monitor individual member's cognitive and affective psychological processes during virtual collaboration to reduce potential risks in virtual collaboration.

• Korean Journal of Biological Psychiatry
• /
• v.24 no.2
• /
• pp.59-67
• /
• 2017

Shift workers experience a disruption in the circadian sleep-wake rhythm, which brings upon adverse health effects such as fatigue, insomnia and decreased sleep quality. Moreover, shift work has deleterious effects on both work productivity and safety. In this review, we present a brief overview of the current literature on the consequences of shift work, especially focusing on attention-associated cognitive decline and related behavioral changes. We searched two electronic databases, PubMed and RISS, using key search terms related to cognitive domains, deleterious effects, and shift work. Twenty studies were eligible for the final review. The consequences of shift work can be classified into the following three categories extracted from the literature review : 1) work accidents ; 2) commuting accidents such as car accidents that occur on the way to and from work ; and 3) attendance management at work (i.e., absenteeism, tardiness, and unscheduled early departure). These cognitive and behavioral consequences of shift work were also found to be associated with sleep disorders in shift workers. Thus, improvements in the shift work system are necessary in order to enhance workers' health conditions, work productivity, and safety.

• Asia-Pacific Journal of Business Venturing and Entrepreneurship
• /
• v.7 no.3
• /
• pp.161-166
• /
• 2012

With recent increase in interest on health through extension of life expectancies of people, desire of smokers to stop smoking is also getting stronger. Korean medicine uses Auricular Acupuncturing as a treatment to stop smoking. This Study examined whether Auricular Acupuncturing is actually effective by manufacturing device that can stimulate lung point and endocrine point that are known to be effective in stop smoking through low frequency stimulation. Firstly, Low Frequency Stimulator for Auricular Acupuncturing to quit smoking (HBN-001) was developed as an experimental device by combining low frequency stimulation to auricular acupuncture points and headset, and was pilot tested on 20 subjects. The average quantity of cigarette smoked prior to the application of the procedure was 12.19, which was reduced to 10.34 cigarettes after 2 weeks with more than 5 sessions of Auricular Acupuncturing. However, there was no statistically significant difference. The changes in the desire to smoke following the procedure included 4 subjects (20%) with no change, 4 (20%) with slight reduction, 4 (20%) with 25%~49% reduction, 6 (30%) with 50%~75% reduction, 1 (5%) with 75%~99% reduction and 1 (5%) with complete elimination of desire to smoke. Changes in how cigarette smoking tasted included 2 subjects (10%) with slight improvement, 7 (35%) with no change, 6 (30%) with slight worsening and 5 (25%) with substantially worsened taste. Based on the results of the Pilot Test, it appears that Auricular Acupuncturing could be affirmatively helpful in quitting smoking, and further researches in greater depth would be necessary in the future.

• The Korean Journal of Petroleum Geology
• /
• v.7 no.1_2 s.8
• /
• pp.28-34
• /
• 1999

The Cretaceous Poongam sedimentary Basin in Kangwon-do, Korea consists alluvial deposits of conglomerates, sandstones, mudstones or siltstones, and volcaniclastics. The Poongam Basin was formed as a fault margin sag or a transpressional basin developed along a strike-slip fault zone, and received huge amount of clastic sediments from the adjacent fault-scaip. It formed an aggrading alluvial fan system and a volcaniclast-supplied marginal lake environment, while tectonic activity and volcanism attenuated toward the end of basin formation. Following the Folk's classification, the sandstones of the Poongam Basin are identified as lithic wackes or feldspathic wackes. The areal and sequential variation of the mineral composition in the sandstones is not distinct. The results of K-Ar age dating from the intruding andesites, volcaniclastics and volcanic fragments in sedimentary rocks show a range of 70 Ma to 84 Ma. It suggests that volcarism occurred sequentially within a relatively short period as the pre-, syn-, and post-depositional events. It was the short period in the late Cretaceous that the basin had evolved i.e., the basin formation, the sediment input and fill, and the , intrusion and extrusion of volcanic rocks occurred. The Poongam sedimentary sequence is a typical tectonic-controlled coarse sedimentary facies which is texturally immature.

• Journal of Life Science
• /
• v.30 no.8
• /
• pp.731-741
• /
• 2020

Coronavirus disease 19 (COVID-19) is caused by SARS-CoV-2 (Severe Acute Respiratory SyndromeCoronavirus 2). To date, seven coronaviruses that can infect humans were reported. Among them, infections with four coronavirus strains (HCoV-229E, HCoV-OC43, HCoV-NL63, and HCoV-HKU1) resulted in mild symptoms such as common cold, whereas SARS-CoV and MERS-CoV caused severe symptoms and epidemics in 2002 and 2012, respectively. In the most recent, SARS-CoV-2 was first reported in Wuhan, China in December 2019 and became a notorious cause of the ongoing global pandemics. To diagnose, treat, and prevent COVID-19, the development of rapid and accurate diagnostic tools, specific therapeutic drugs, and safe vaccines essentially are required. In order to develop these powerful tools, it is prerequisite to understand a phenotype, a genotype, and life cycle of SARS-CoV-2. Diagnostic techniques have been developing rapidly around world and many countries take the fast track system to accelerate approval. Approved diagnostic devices are rapidly growing facing to urgent demand to identify carriers. Currently developed commercial diagnostic devices are divided into mainly two categories: molecular assay and serological & immunological assay. Molecular assays begins the reverse transcription step following polymerase chain reaction or isothermal amplification. Immunological assay targets SARS-CoV-2 antigen or anti-SARS-CoV-2 antibody of samples. In this review, we summarize the phenotype, genome structure and gene expression of SARS-CoV-2 and provide the knowledge on various diagnostic techniques for SARS-CoV-2.