• Journal of the Korean Association of Oral and Maxillofacial Surgeons
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• v.50 no.1
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• pp.13-26
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• 2024

Objectives: The aim of this study was to perform a comparative analysis of the ultrastructural and chemical composition of sialoliths, tonsilloliths, and antroliths and to describe their growth pattern. Materials and Methods: We obtained 19 specimens from 18 patients and classified the specimens into three groups: sialolith (A), tonsillolith (B), and antrolith (C). The peripheral, middle, and core regions of the specimens were examined in detail by histology, micro-computed tomography (micro-CT), scanning electron microscopy (SEM), energy dispersive X-ray spectroscopy, and transmission electron microscopy (TEM). Results: In the micro-CT, group A showed alternating radiodense and radiolucent layers, while group B had a homogeneous structure. Group C specimens revealed a compact homogeneous structure. Histopathologically, group A showed a laminated, teardrop-shaped, globular structure. Group B demonstrated degrees of immature calcification of organic and inorganic materials. In group C, the lesion was not encapsulated and showed a homogeneous lamellar bone structure. SEM revealed that group A showed distinct three layers: a peripheral multilayer zone, intermediate compact zone, and the central nidus area; groups B and C did not show these layers. The main elemental components of sialoliths were O, C, Ca, N, Cu, P, Zn, Si, Zr, F, Na, and Mg. In group B, a small amount of Fe was found in the peripheral region. Group C had a shorter component list: Ca, C, O, P, F, N, Si, Na, and Mg. TEM analysis of group A showed globular structures undergoing intra-vesicular calcification. In group B, bacteria were present in the middle layer. In the outer layer of the group C antrolith, an osteoblastic rimming was observed. Conclusion: Sialoliths had distinct three layers: a peripheral multilayer zone, an intermediate compact zone and the central nidus area, while the tonsillolith and antrolith specimens lacked distinct layers and a core.

• Journal of Korean Dental Hygiene Science
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• v.6 no.2
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• pp.91-100
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• 2023

Background: This study evaluated the learning outcomes of dental hygiene students' ethical consciousness and ethical decision-making competence through dental ethics courses conducted in some universities. Methods: The subjects were 35 and 29 fourth-year dental hygiene students at G University in the first semester of 2021 and 2022, respectively, and 53 and 43 third-year dental hygiene students at D University, respectively, for a total of 160 students. After implementing the dental hygiene ethics course, classroom performance was evaluated in terms of moral sensitivity, confidence in making ethical decisions, classroom practicality, learning outcomes, and class satisfaction. Statistical analysis was conducted using independent t-test and paired t-test, and the statistical significance level was 0.05. Results: Both universities reported an increase in moral sensitivity and confidence in ethical decision-making after the course (p<0.001). Classroom practicality and class satisfaction for the dental hygiene ethics course did not differ between disciplines and were rated positively with a score of 4 or higher (p>0.05). Learning outcomes were higher among 4-year students than 3-year students (p<0.001). Conclusions: It was evaluated that the ethics in dental hygiene curriculum can strengthen students' competence in ethical decision-making, including moral sensitivity and confidence in solving ethical problems in dental hygiene.

• International Journal of Stem Cells
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• v.16 no.1
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• pp.66-77
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• 2023

Background and Objectives: We compared the efficacy and safety of human bone marrow-derived mesenchymal stem cells (hBMSC), delivered at different doses and via different injection routes in an animal model of chronic kidney disease. Methods and Results: A total of ninety 12-week-old rats underwent 5/6 nephrectomy and randomized among nine groups: sham, renal artery control (RA-C), tail vein control (TV-C), renal artery low dose (RA-LD) (0.5×10⁶ cells), renal artery moderate dose (RA-MD) (1.0×10⁶ cells), renal artery high dose (RA-HD) (2.0×10⁶ cells), tail vein low dose (TV-LD) (0.5×10⁶ cells), tail vein moderate dose (TV-MD) (1.0×10⁶ cells), and tail vein high dose (TV-HD) (2.0×10⁶ cells). Renal function and mortality of rats were evaluated after hBMSC injection. Serum blood urea nitrogen was significantly lower in the TV-HD group at 2 weeks (p<0.01), 16 weeks (p<0.05), and 24 weeks (p<0.01) than in the TV-C group, as determined by one-way ANOVA. Serum creatinine was significantly lower in the TV-HD group at 24 weeks (p<0.05). At 8 weeks, creatinine clearance was significantly higher in the TV-MD and TV-HD groups (p<0.01, p<0.05) than in the TV-C group. In the safety evaluation, we observed no significant difference among the groups. Conclusions: Our findings confirm the efficacy and safety of high dose (2×10⁶ cells) injection of hBMSC via the tail vein.

• Journal of Korean Society of Forest Science
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• v.98 no.4
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• pp.399-408
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• 2009

We investigated the improvement of immuno-modulatory activities of sap of Acer mono and A. okamotoanum encapsulated with edible polymers. Anticancer activities and immune activities such as human B and T cell growth, secretion of cytokines and natural killer cell growth were observed. Both human immune B and T cells were increased up to 30~50% by the addition of nano particle sap of Acer mono and A. okamotoanum. The secretion of Interleukin-6 (IL-6) and Tumor necrosis factor-a (TNF-a) from human immune B and T cells were also significantly increased compare to the control. Natural Killer (NK) cell growth was enhanced to $19.4{\times}10^5$ cells/mL in adding nano encapsulated sap of A.okamotoanum. The cytotoxicity of the sample on normal human lung cell (HEL299) was below 19.8% in adding 1.0 mg/mL of the nano particle sap of A. okamotoanum. Generally, the growth of all three human lung adenocarcinoma, human stomach adenocarcinoma and human liver adenocarcinama was inhibited up to 85% in adding 1.0 mg/mL of the encapsulated sap. Interestingly enough, the encapsulated sap was completely penetrated into human cancer cells within 30 min after addition. It showed that the encapsulation of the sap definitely increased its biological activities, which can expand its use to wide range of food industries.

• Culinary science and hospitality research
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• v.21 no.6
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• pp.103-119
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• 2015

This study was carried out to evaluate the quality of characteristics of Takju, Yakju, and spirit made from Bunkuk(flour), Phellinus linteus and Ginger kuk. The sacharogenic power of Nuruks and pH, brix, acidity, cell numbers of yeast, and alcohol content of Deotsuls were analysed; flavors, organic acids, and sensory evaluation of Takju, Yakju, and spirit were employed in the analysis of this current study. Results showed that the saccharogenic power of Phellinus linteus kuk after fermentation of Nuruks showed the highest level, and Phellinus linteus kuk and Ginger kuk showed the same level after dry Nuruks. During fermentation of Deotsuls, pH and brix decreased with increased fermentation time, while acidity increased with increased fermentation time. Cell numbers of yeast were found to be at the highest level in Phellinus linteus kuk on the first day of fermentation, and it was the same result in the final stage(p<0.05). Alcohol content increased with an increase in fermentation time, and showed no significant difference between control and test in the final stage of fermentation. In terms of analysis of flavor components, acetone and n-amyl alcohol were not detected in Takju, Yakju, and spirit. n-butanol was detected at the highest value, followed by i-amyl alcohol. Fusel oil was detected at the highest level in spirit fermented by Bunkuk. In analysis of organic acids, lactic acid showed the highest content followed by acetic acid. Very small amounts of acetic acid were detected in the spirit and other organic acids were not detected. In sensory evaluation, Takju, Yakju, and spirit made from Phellinus linteus kuk showed the highest score. As a result of this study, Phellinus linteus kuk presented the most desirable Nuruk in order to make Takju, Yakju, and spirit.

• Korean Journal of Air-Conditioning and Refrigeration Engineering
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• v.29 no.6
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• pp.327-340
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• 2017

This article reviews the papers published in the Korean Journal of Air-Conditioning and Refrigeration Engineering during 2016. It is intended to understand the status of current research in the areas of heating, cooling, ventilation, sanitation, and indoor environments of buildings and plant facilities. Conclusions are as follows. (1) The research works on the thermal and fluid engineering have been reviewed as groups of flow, heat and mass transfer, the reduction of pollutant exhaust gas, cooling and heating, the renewable energy system and the flow around buildings. CFD schemes were used more for all research areas. (2) Research works on heat transfer area have been reviewed in the categories of heat transfer characteristics, pool boiling and condensing heat transfer and industrial heat exchangers. Researches on heat transfer characteristics included the results of the long-term performance variation of the plate-type enthalpy exchange element made of paper, design optimization of an extruded-type cooling structure for reducing the weight of LED street lights, and hot plate welding of thermoplastic elastomer packing. In the area of pool boiling and condensing, the heat transfer characteristics of a finned-tube heat exchanger in a PCM (phase change material) thermal energy storage system, influence of flow boiling heat transfer on fouling phenomenon in nanofluids, and PCM at the simultaneous charging and discharging condition were studied. In the area of industrial heat exchangers, one-dimensional flow network model and porous-media model, and R245fa in a plate-shell heat exchanger were studied. (3) Various studies were published in the categories of refrigeration cycle, alternative refrigeration/energy system, system control. In the refrigeration cycle category, subjects include mobile cold storage heat exchanger, compressor reliability, indirect refrigeration system with $CO_2$ as secondary fluid, heat pump for fuel-cell vehicle, heat recovery from hybrid drier and heat exchangers with two-port and flat tubes. In the alternative refrigeration/energy system category, subjects include membrane module for dehumidification refrigeration, desiccant-assisted low-temperature drying, regenerative evaporative cooler and ejector-assisted multi-stage evaporation. In the system control category, subjects include multi-refrigeration system control, emergency cooling of data center and variable-speed compressor control. (4) In building mechanical system research fields, fifteenth studies were reported for achieving effective design of the mechanical systems, and also for maximizing the energy efficiency of buildings. The topics of the studies included energy performance, HVAC system, ventilation, renewable energies, etc. Proposed designs, performance tests using numerical methods and experiments provide useful information and key data which could be help for improving the energy efficiency of the buildings. (5) The field of architectural environment was mostly focused on indoor environment and building energy. The main researches of indoor environment were related to the analyses of indoor thermal environments controlled by portable cooler, the effects of outdoor wind pressure in airflow at high-rise buildings, window air tightness related to the filling piece shapes, stack effect in core type's office building and the development of a movable drawer-type light shelf with adjustable depth of the reflector. The subjects of building energy were worked on the energy consumption analysis in office building, the prediction of exit air temperature of horizontal geothermal heat exchanger, LS-SVM based modeling of hot water supply load for district heating system, the energy saving effect of ERV system using night purge control method and the effect of strengthened insulation level to the building heating and cooling load.

• The Korean Journal of Malacology
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• v.30 no.4
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• pp.321-331
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• 2014

Patinopecten yessoensis is known to be farmed only in the northern part of the East Sea today. In an attempt to extend its production area, we have conducted experiments both in the northern and southern parts of the East Sea and studied on their growth in an aim to use the results for increasing overall productivity of the species. Early juvenile scallops producted in February 2014 showed an average shell length of $0.23{\pm}0.002$. The high growth group showed an average shell length and shell height of $4.11{\pm}0.08mm$ and $4.28{\pm}0.09mm$, respectively, in June while they were $23.63{\pm}3.4mm$ and $24.19{\pm}4.5mm$ in October. The low growth group showed an average shell length and shell height of $2.23{\pm}0.7mm$ and $1.99{\pm}0.9mm$, respectively, in June while they were $1.99{\pm}0.9mm$ and $17.59{\pm}4.5mm$ in October. The daily growth rate of the high growth group was 0.037 mm/day and 0.027 mm/day for the low growth group. In August, we measured the shell length of Patinopecten yessoensis from Yangyang-gun, Gangneung-si, Yeongdeok-gun, and Pohang-si. Patinopecten yessoensis from Pohang-si showed the best growth performance with its shell length of $26.90{\pm}3.6mm$. Patinopecten yessoensis from Yeongdeok was the second largest with its shell length of $23.56{\pm}3.4mm$. We presume that optimal water temperature and phytoplankton abundance of the two regions have contributed to the good growth performance of the species.

• Horticultural Science & Technology
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• v.33 no.6
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• pp.877-882
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• 2015

This study was carried out treatment of polyethylene glycol (PEG) in order to increase of survival rate of acclimated plants of strawberry's in vitro plantlets through bioreactor culture. We used PEG with molecular weight 6000 (PEG 6000) in this study. Concentration of PEG is non-treatment, 5, 10, 15, and $20g{\cdot}L^{-1}$ each bioreactor. $5g{\cdot}L^{-1}$ of PEG was treated at $1^{st}$, $2^{nd}$, $3^{rd}$, $4^{th}$, and $5^{th}$ week during culture. We investigated growth characteristics of in vitro plantlets after 6 weeks cultivation. Growth amount of all PEG treatment decreased as compared to non-treatment. The more concentration increased, the more plant growth decreased. In $5g{\cdot}L^{-1}$ of PEG, shoot length was shorter than non-treatment that shoot length was 7.9 cm and especially fresh weight that is 1.6 g was more decrease than non-treatment. Shoot length was ranged 3.0-3.9 cm at $1^{st}$ week treatment to $4^{th}$ week treatment of $5g{\cdot}L^{-1}$ PEG. The shoot length was not significant by 5.3 cm at $5^{th}$ week treatment. The survival rate was improved 5.4% at the treatment of $4^{th}$ week and was improved 8.7% at the $5^{th}$ week as compared to non-treatment. In order to improve of survival rate of strawberry' in vitro plantlets through bioreactor culture, the method is suitable that adding $5g{\cdot}L^{-1}$ of PEG in the medium and $5^{th}$ week's treatment is suitable.

• Journal of the Korean earth science society
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• v.27 no.2
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• pp.159-176
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• 2006

Geographic factors and mathmatical location of the Korean Peninsula have great influences on the variation patterns and appearances over a period of ten days of summer precipitation. In order to clarify the influence of several climate factors on precise climate classification in the middle part region of the Korea, weather entropy and the information ratio were calculated on the basis of information theory and of the data of 25 site observations. The data used for this study are the daily precipitation phenomenon over a period of ten days of summer during the recent thirteen years (1991-2003) at the 25 stations in the middle part region of the Korea. It is divided into four classes of no rain, $0.1{\sim}10.0mm/day,\;10.1{\sim}30.0mm/day$, 30.1mm over/day. Their temporal and spatial change were also analyzed. The results are as follows: the maximum and minimum value of calculated weather entropy are 1.870 bits at Chuncheon in the latter ten days of July and 0.960 bits at Ganghwa during mid September, respectively. And weather entropy in each observation sites tends to be larger in the beginning of August and smaller towards the end of September. The largest and smallest values of weather representative ness based on information ratio were observed at Chungju in the beginning of June and at Deagwallyeong towards the end of July. However, the largest values of weather representativeness came out during the middle or later part of September when 15 sites were adopted as the center of weather forecasting. The representative core region of weather forecasting and climate classification in the middle part region of the Korea are inside of the triangle region of the Buyeo, Incheon, and Gangneung.

• Journal of the Korean earth science society
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• v.39 no.1
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• pp.53-66
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• 2018

The information of surface reflectance ($R_{sfc}$) is important for the heat balance and the environmental/climate monitoring. The $R_{sfc}$ sensitivity to error-induced variables for the Geostationary Environment Monitoring Spectrometer (GEMS) retrieval from geostationary-orbit satellite observations at 300-500 nm was investigated, utilizing polar-orbit satellite data of the MODerate resolution Imaging Spectroradiometer (MODIS) and Ozone Mapping Instrument (OMI), and the radiative transfer model (RTM) experiment. The variables in this study can be cloud, Rayleigh-scattering, aerosol, ozone and surface type. The cloud detection in high-resolution MODIS pixels ($1km{\times}1km$) was compared with that in GEMS-scale pixels ($8km{\times}7km$). The GEMS detection was consistent (~79%) with the MODIS result. However, the detection probability in partially-cloudy (${\leq}40%$) GEMS pixels decreased due to other effects (i.e., aerosol and surface type). The Rayleigh-scattering effect in RGB images was noticeable over ocean, based on the RTM calculation. The reflectance at top of atmosphere ($R_{toa}$) increased with aerosol amounts in case of $R_{sfc}$<0.2, but decreased in $R_{sfc}{\geq}0.2$. The $R_{sfc}$ errors due to the aerosol increased with wavelength in the UV, but were constant or slightly decreased in the visible. The ozone absorption was most sensitive at 328 nm in the UV region (328-354 nm). The $R_{sfc}$ error was +0.1 because of negative total ozone anomaly (-100 DU) under the condition of $R_{sfc}=0.15$. This study can be useful to estimate $R_{sfc}$ uncertainties in the GEMS retrieval.