• Journal of the korean academy of Pediatric Dentistry
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• v.36 no.2
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• pp.227-236
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• 2009

The purpose of this study is to examine the acidity of beverages that are sold for children in the market and to estimate by experiment the degree of the enamel erosion of deciduous teeth that is attributed to the beverages. The pH value of children beverages among top sale list in Seoul and Gyeonggi province were measured. And 7 beverages with the pH value of 3.5 or lower were selected. The enamel erosion of deciduous teeth by the children beverages for 1, 5, 10, and 30 minutes respectively was examined. The results were as follows: 1. The acidity of most of the children beverages examined in this study was the pH level of 5.5 or lower that can cause the tooth erosion. 2. The microhardness value of the enamel of deciduous teeth was lower as exposing it to children beverages. The reduction of surface microhardness value was significant from 1 minute after the exposure, and the reduction was continuously observed until 30 minutes has passed. 3. The higher the acidity of beverages, the larger the reduction in microhardness value caused after the exposure of 30 minutes to the beverages. There was no significant relation between the acidity of beverages and the reduction rate of surface microhardness value. The other factors such as calcium, phosphorus, and fluorine or buffering of the beverages may affect the enamel erosion.

• Asian-Australasian Journal of Animal Sciences
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• v.22 no.6
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• pp.857-864
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• 2009

This experiment was conducted to investigate the effects of interaction between $1{\alpha}$-hydroxycholecalciferol ($1{\alpha}$-OH $D_3$) and phytase on growth performance, parameters of tibia and plasma, and meat quality of 1- to 21-d-old broilers. Two hundred and forty male, 1-d-old Arbor Acres broilers were randomly assigned to 20 cages, with 12 chicks per cage. Five treatments were designed, with four cages each. A 2${\times}$2 factorial experiment was designed to test 0 and 5 ${\mu}g/kg$ of $1{\alpha}$-OH $D_3$ in combination with 0 and 500 U/kg of phytase. A basal diet was formulated to contain 2.9 g/kg of non-phytate phosphorus (NPP), and the control diet was formulated to contain a normal level of NPP (4.5 g/kg). Results showed that $1{\alpha}$-OH $D_3$ alone increased tibia ash, contents of calcium and phosphate, breaking strength, concentrations of plasma calcium and phosphate, and water-holding capacity of breast and thigh meat, while it decreased growth of broilers. Phytase alone improved performance and tibia quality. Although growth of broilers was lower than that of the positive control when the diet was supplemented with $1{\alpha}$-OH $D_3$ and phytase, tibia quality was significantly improved by the addition of $1{\alpha}$-OH $D_3$ and phytase. These data suggest that interaction between $1{\alpha}$-OH $D_3$ and phytase at 2.9 g/kg of dietary NPP could significantly increase bone quality of 1- to 21-d-old broilers, while not improving growth performance.

• Journal of Korean Society of Forest Science
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• v.81 no.4
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• pp.310-319
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• 1992

Vegetational data obtained from 24 quadrats of Mt. Paekdu area were analysed by applying two multivariate methods : two-way indicator species analysis(TWIMSPAN) for classification and detrended canonical correspondence analysis(DCCA) for ordination. DCCA technique allowed to extract the ordination axes that could be related to 9 environmental factors. The dominant tree species distributed in the region between 1,700-1,950m from sea level were Betula ermanii, Larix olgensis, Abies nephrolepis, and Picea jezoensis in descending order. The dominant tree species distributed in the region between 1.300-1.500m were Abies nephrolepis, Pinus koraiensis, Larix olgensis, Betula mandshurica, and Picea jezoensis in descending order. The available phosphorus content in forest soil ranged from 7 to 1.153ppm. The distribution of the major communities showed a close relationship with elevation gradient. From high to low elevation, the communities of Alnus fruticosa var. mandshurica, Betula ermanii, Larix olgensis, Abies nephrolepis, Picea jezoensis, Pinus koraiensis, and Quercus mongolica were found in descending order. At the communities where Betula ermanii was dominant, Betula ermanii forest was distributed in the high elevation area, Betula ermanii-Larix olgensis forest in the good nutrition of organic matter and $K^+$, and Abies nephrolepis forest in the good nutrition of $Mg^{{+}{+}}$ and $Ca^{{+}{+}}$. The most dominant factor influencing community distribution was elevation.

• Korean Journal of Environmental Agriculture
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• v.21 no.4
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• pp.237-242
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• 2002

A survey on four tributaries along with Mankyeong River was carried out to get the information far the water quality improvement and control. Typical paddy farming were major agricultural practices in Kosancheon and Soyangcheon. Iksancheon was livestock raising watershed. Chucheon was urban watershed. Water quality in six sites of main stream and four sites of tributaries in Mankyeong River were investigated from May to August in 2001. The concentration of nutrient in main stream of Mankyeong River were in the range of 3.78$\sim$12.68 mg/L for total nitrogen, 0.043$\sim$0.864 mg/L for total phosphorus, 2.59$\sim$13.29 mg/L for BOD and 12.9$\sim$119.5 mg/L for COD, respectively. Water quality of Mankyeong River mostly exceeded the standard water quality criteria of Korea. Major causes of water pollution were evaluated as sewage of swine and urban area. Among the four tributaries, water quality in agricultural practices, Kosancheon and Soyangcheon was relatively less polluted. While, the highest level of water pollution measured in Iksancheon was due to livestock. The water quality of Iksancheon and Chucheon was generally more polluted in the dry period than in rainy period.

• Applied Chemistry for Engineering
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• v.26 no.5
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• pp.609-614
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• 2015

This study was to investigate the production of combustion toxic gases of pinus rigida specimens treated with pyrophosphoric acid (PP)/4ammonuium ion ($4NH_4{^+}$), methylenepiperazinomethyl-bis-phosphonic acid (PIPEABP) and PIPEABP/$4NH_4{^+}$. Each pinus rigida plates was painted in three times with 15 wt% in the aqueous solution followed by drying the species at room temperature. Emission of combustion toxic gases was examined by the cone calorimeter (ISO 5660-1). First-time to peak mass loss rate (1st-$TMLR_{peak}$) treated with chemicals was delayed upto 66.7~250.0% compared to those of untreated specimens. For test pieces treated with the chemicals, the emission of peak carbon monoxide ($CO_{peak}$) values of 0.0136~0.0178% and peak carbon dioxide ($CO_{2\;peak}$) value of 0.04432~0.3648% were obtained, which were higher than those for the virgin plate. In particular, oxygen emission is much higher than the level of 15% which can be fatal to humans. Therefore, the resulting risk could be eliminated. However it is supposed that the combustion-toxicities were partially increased compared to those of virgin plate.

• The Korean Journal of Food And Nutrition
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• v.22 no.4
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• pp.669-677
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• 2009

The purpose of this study was to compare the anthropometry, nutrient intakes, dietary - related behaviors and health - related behaviors of male workers that were divided according to their alcohol consumption. The mean height, weight and BMI of all subjects were 172.0$\pm$5.8 cm, 67.8$\pm$9.3 kg and 22.9$\pm$2.6 kg/$m^2$, respectively. The WHR was higher in the heavy drinking group than in the other groups(p<0.01), while the other anthropometric indices were not significantly different among the three groups. The calorie intake was highest(p<0.001) in the heavy drinking group(3,270.4$\pm$686.5 kcal), followed by moderate(2,602.8$\pm$415.8 kcal) drinking group and light drinking group(2,341.5$\pm$449.4 kcal). As alcohol consumption increased, there was a decrease in the percent of energy derived from carbohydrates and lipids, while there was an increase in the percent of energy derived from proteins and alcohol(p<0.001). The heavy and moderate drinking groups had a highers intake of protein compared to the light drinking group, and the heavy drinking group had a higher intake of lipid compared to the light and moderate drinking groups(p<0.01). The intakes of vitamin $B_2$, niacin and phosphorus were lower in the moderate group than the other groups(p<0.01). The average MAR(Mean adequacy ratio) was 1.44$\pm$0.35 and the intake of all nutrients, except for folic acid, was much higher than the Korean RI(Recommended intake). The fruit intake frequency and sleeping hours were the lowest in the heavy drinking group(p<0.05) and the subjects preferred the following order of food products when they drink: meat(42.5%), fish & shellfish(30.0%), fruit & vegetable(22.5%) and others(5.0%) as a side dish. The average rates of smoking and exercise for all the subjects were 77.5% and 67.5%, respectively. The results of this study showed that heavy alcohol drinkers were more prone to abdominal obesity and related chronic degenerative diseases, indicating the need for extensive nutritional education for heavy alcohol drinkers.

• Korean Journal of Poultry Science
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• v.30 no.3
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• pp.169-175
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• 2003

This experiment was conducted to study the optimum energy feeding regimens fur broiler breeders peaked in winter season with 400 caged hens of Ross strain. Four energy supply regimens which were different in daily energy allotment during laying period were employed for 40 weeks from 24 to 64 weeks of age. All experimental diets were formulated to contain 2,750 kcal ME/kg with adjustments made in total feed allotment to provide the desired energy levels. Total consumption of the feed would provide 20 g of protein, 4 g of calcium and 0.35 g of available phosphorus. There were no difference in hen-day egg production and average egg weight among the regimens of energy supply. Feed, ME and feed cost required per egg or per kg egg were significantly increased as the level of energy allotment increased(p<0.05). It was concluded that the energy supply regimen, which supplied 280 kcal ME per day at the age of 24 weeks and then increased the energy supply up to 400 kcal ME per day at the peak period of 30∼34 weeks of age, was superior in feed, ME and feed cost required per egg or per kg egg without any adverse effect on eg production and egg weight.

• Journal of Veterinary Clinics
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• v.29 no.6
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• pp.435-440
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• 2012

This study was designed to evaluate the clinical efficacy and safety of Rhubarb extracts ($Rubenal^{(R)}$) in dogs with chronic renal failure (CRF). Client-owned 40 dogs with CRF graded International renal interest Society (IRIS) II-III were enrolled in this study. The dogs were equally allocated and blindly administered with $Rubenal^{(R)}$ or placebo. The following items were evaluated at day 0, 30, 90 and 180: body condition score (BCS), clinical score (appetite, polydipsia/polyuria, quality of life score), hemogram (WBC, RBC, PCV), serum biochemistry (ALT/AST, ALP, Creatinine/BUN, total protein, albumin), serum electrolyte (Na, K, Cl, Ca, P), systolic blood pressure, urinalysis (UPC, USG) and IRIS stage. In this study, we found that the $Rubenal^{(R)}$ preparation was well tolerated by dogs and induced no adverse effects. Statistically significant improvements were observed in clinical score (quality of life score by vet and clients), serum BUN and creatinine levels, serum phosphorus concentration, level of proteinuria, and the IRIS score of CRF in dogs after 6 month of treatment of $Rubenal^{(R)}$. Those findings suggested that the Rhubarb extracts can improve the clinical signs of CRF (i.e. azotemia, hypertension, proteinuria, hyperphosphoremia) and the quality of life (i.e. BCS, clinical score) and can retard the progression of CRF in dogs. Therefore the Rhubarb extracts can be a good supplementary drug for treating dogs with subclinical and clinical renal diseases. However, care should be taken for interpreting our result, because this study is not double-blinded controlled study but pilot study.

• Journal of Korea Water Resources Association
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• v.40 no.8
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• pp.601-615
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• 2007

A selective withdrawal method has been widely used to control the quality of water released from a stratified reservoir and to improve downstream ecosystem habitats. Recently, several existing reservoir withdrawal facilities have been modified to accommodate multi-level water intake capabilities in order to adapt the impact of long-term discharge of high turbidity flow. The purpose of this study was to assess the effect of selective withdrawal method on the control of downstream turbidity and its impact on water quality in Daecheong Reservoir. A laterally integrated two-dimensional hydrodynamic and eutrophication model, which was calibrated and validated in the previous studies, was applied to simulate the temporal variations of outflow turbidity with various hypothetical selective withdrawal scenarios. In addition, their impacts on the algal growth as well as water quality constituents were analyzed in three different spatial domains of the reservoir The results showed that the costly selective withdrawal method would provide very limited benefits for downstream turbidity control during two years of consecutive simulations for 2004-2005. In particular, an excessive withdrawal from the epilimnion zone for supplying upper layer clean water resulted in movement of turbidity plume that contained high phosphorus concentrations upward photic zone, and in turn increased algal growth in the lacustrine zone.

• Korean Journal of Environmental Agriculture
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• v.16 no.2
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• pp.199-205
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• 1997

Water quality of streams and ground water from areas of different agricultural practices in the small catchments of the Han River basin was investigated. Water samples were collected from upper, middle and lower reaches of the Han River Basin where three types of agricultural management have been practiced : (1) highland agriculture and livestocks in Daegwanryung area, (2) typical upland and paddy farmings in Dunnae (Jucheon River) and Chuncheon (Soyang River) areas, and (3) intensive farming in the plastic film house in Guri area (Wangsuk stream). Water quality was monitored for EC, pH, COD, TSS, N, rations and anions. Concentrations of N, especially nitrate, and phosphorus in both stream and ground water exceeded the standard water quality criteria in many cases, but those of heavy metals were non-detectable or trace in most cases, except for Wangsuk stream where a high level was detected in a specific sampling time. Chemical criteria such as pH, EC and COD of the stream were suitable for irrigation purpose, but nitrate concentrations in ground water used in the intensive plastic film house were high enough to require a special management consideration. A model on the irrigation water quality incorporating EC and nitrate concentrations was suggested in view of fertilizer management and environmental quality.