• Journal of the korean academy of Pediatric Dentistry
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• v.37 no.1
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• pp.1-12
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• 2010

The aim of this study was to evaluate the preventive effect of commercially available anticariogenic products, specifically, the tooth cream containing Casein phosphopeptide-amorphous calcium phosphate(CPP-ACP), fluoride varnish and low-level fluoride mouthrinse on enamel erosion induced by carbonated beverage in a short period of time. Enamel specimens were treated as follows and were then kept in artificial saliva for 24 hours followed by further processing by alternately soaking them in Cola beverage and in distilled water for 1 minute each five times. Group 1: control group (no treatment) Group 2: tooth cream with CPP-ACP Group 3: fluoride varnish (1,000 ppm F) Group 4: low-level fluoride mouthrinse (227 ppm F) Group 5: fluoride varnish + tooth cream with CPP-ACP Group 6: low-level fluoride mouthrinse + tooth cream with CPP-ACP Microhardness and erosion depth were measured and the mineral loss of each specimen was evaluated by measuring the volumetric fluorescence change(${\Delta}Q$) against the stable fluorescent grid using quantitative light-induced fluorescence(QLF). The experiment lasted for 6 days repeated each day. The results were as follows: 1. The microhardness was increased as follows: Group $1{\leq}2{\leq}4$<6<$3{\fallingdotseq}5$. 2. The mean erosion depth was increased as follows: Group $5{\fallingdotseq}3$<6<$4{\fallingdotseq}2{\fallingdotseq}1$. 3. The ${\Delta}Q$ was increased as follows: Group $1{\fallingdotseq}2{\leq}4{\leq}6{\leq}3{\fallingdotseq}5$. The decrement of ${\Delta}Q$ was similar between group 1 and 2, group 4 and 6 and group 3 and 5. 4. The ${\Delta}Q$ showed positive correlation with microhardness (r=0.96, p<0.05), while it was negatively correlated to erosion depth (r=-0.96, p<0.05).

• Korean Journal of Remote Sensing
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• v.37 no.5_1
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• pp.959-974
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• 2021

Forel-Ule Index (FUI) is an index which classifies the colors of inland and seawater exist in nature into 21 gradesranging from indigo blue to cola brown. FUI has been analyzed in connection with the eutrophication, water quality, and light characteristics of water systems in many studies, and the possibility as a new water quality index which simultaneously contains optical information of water quality parameters has been suggested. In thisstudy, Ocean Colour-Climate Change Initiative (OC-CCI) based 4 km FUI was spatially downscaled to the resolution of 500 m using the Geostationary Ocean Color Imager (GOCI) data and Random Forest (RF) machine learning. Then, the RF-derived FUI was examined in terms of its correlation with various water quality parameters measured in coastal areas and its spatial distribution and seasonal characteristics. The results showed that the RF-derived FUI resulted in higher accuracy (Coefficient of Determination (R²)=0.81, Root Mean Square Error (RMSE)=0.7784) than GOCI-derived FUI estimated by Pitarch's OC-CCI FUI algorithm (R²=0.72, RMSE=0.9708). RF-derived FUI showed a high correlation with five water quality parameters including Total Nitrogen, Total Phosphorus, Chlorophyll-a, Total Suspended Solids, Transparency with the correlation coefficients of 0.87, 0.88, 0.97, 0.65, and -0.98, respectively. The temporal pattern of the RF-derived FUI well reflected the physical relationship with various water quality parameters with a strong seasonality. The research findingssuggested the potential of the high resolution FUI in coastal water quality management in the Korean Peninsula.

• Journal of the Korean Society of Food Science and Nutrition
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• v.38 no.6
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• pp.709-720
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• 2009

This study was conducted to identify daily caffeine intakes in beverages for elementary school children and to evaluate its effectiveness after nutrition education. The caffeine contents of 140 commercial beverages were analysed by high performance liquid chromatography-ultraviolet detector (HPLC-UV) and information about their consumption were obtained by surveying 267 children. Researchers gave nutrition education to the children, who were 6 to 11 years old and attended 9 classes of 3 elementary schools, by lecture, Powerpoint file and moving picture. Their preference and intake amount on beverages were investigated by questionnaire before and after nutrition education. The order on caffeine contents was coffee ($33.8{\pm}2.4{\sim}49.1{\pm}5.6\;mg/100\;mL$)> coffee milk ($10.6{\pm}3.3\;mg/100\;mL$)> cola ($6.0{\pm}2.4\;mg/100\;mL$)> green black oolong tea drink ($6.0{\pm}2.4\;mg/100\;mL$)> chocolate milk and chocolate drink ($1.6{\pm}0.7{\sim}1.7\;mg/100\;mL$)> black ice tea mix ($1.3{\pm}1.7\;mg/100\;mL$). The order on children's preference was carbonated drink and fruit and vegetable drink (27%)> sports drink (26%)> processed cocoa mix (7%)> milk (6%)> vitamin & functional drink (3%)> green tea drink (2%)> black tea drink and coffee (1%). The average daily caffeine intakes except tea drink was $5.9{\pm}11.2$ mg/person/day ($0.17{\pm}0.32$ mg/kg bw/day), ranged from $0.0{\sim}80.5$ mg/person/day for children. The sources of caffeine were coffee 57% (3.4 mg/person/day), coffee milk 20% (1.2 mg/person/day), carbonated drink 15% (0.9 mg/person/day), chocolate milk and chocolate drink 6% (0.4 mg/person/day), and vitamin & functional drink 2% (0.1 mg/person/day). After nutrition education, the preference of carbonated drink, coffee, vitamin drinks & functional drink was decreased significantly (p<0.05, p<0.05, p<0.01) and the intakes of carbonated drink, chocolate milk & chocolate drink, and vitamin & functional drink were also decreased significantly (p<0.01, p<0.05, p<0.01). This study has shown that nutrition education influences the preference and the intake behavior of caffeinated beverages.