• Asian-Australasian Journal of Animal Sciences
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• v.9 no.2
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• pp.203-210
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• 1996

A 13-month study was conducted to determine the monthly variation of crude protein(CP), cell contents(CC), fiber fractions and mineral concentrations of paragrass [Brachiaria mutica (Forsk.) Stapf.] and stargrass (Cynodon plectostachyum Pilger) and to estimate the correlations among the nutrient fractions and climatic factors. The forage samples collected by hand plucking were found to contain CP and mineral concentrations. i.e. calcium(Ca), magnesium(Mg), potassium(K) and zinc(Zn) above the critical levels based on ruminant veeds. Monthly differences(p<0.05) were observed in all CP, CC, neutral detergent fiber(NDF), acid detergent fiber(ADF), hemicellulose(HE), cellulose(CE) and acid detergent lignin(ADL) between the two grass species. Monthly differences(p<0.05) were also observed in all concentrations of forage Ca, K, phosphorus(P), copper(Cu) and Zn except in Mg of both grasses and K of stargrass. Species differences(p<0.05) were observed in all nutrient fractions except Mg and K concentrations. Rainfall had positive correlations to CP, P(p<0.01) and CC(p<0.05); it had negative correlations to NDF(p<0.05). ADF, CE, Ca, Cu and Zn(p<0.01). Temperature, humidity and daylength had also some correlations to various nutrient fractions.

• Journal of Korean Society of Forest Science
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• v.94 no.5 s.162
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• pp.302-306
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• 2005

Litterfall and nutrient inputs were measured in even-aged coniferous plantations (a 31-year-old Pinus rigida and a 31-year-old Larix leptolepis) on a similar site condition in the Forest Practice Research Center, Gyeonggi Province. Litterfall was collected monthly from circular littertraps (collecting area: $0.50m^2$) for three years between April 1997 and February 2000. Average total annual litterfall was significantly higher for pine (5,802 kg/ha/yr) than for larch (4,562 kg/ha/yr) plantations. Needle litter in both plantations accounted for about 63% of total litterfall. Litterfall in the larch was distributed as follows: needle > other leaf > branch > miscellaneous > bark, while it was needle > miscellaneous > other leaf > branch > bark in the pine plantation. There was no temporal variation in needle litter, other leaf and bark during the 3 year study period. The concentrations of all nutrients (N, P, K, Ca, Mg) in needle litter were significantly higher in the larch than in the pine plantations. The annual nutrient concentration of needle litter in the larch varied among the years, whereas no year variation of needle litter was in the pine except for phosphorus (P). Nitrogen (N) and P inputs by needle litter were significantly higher for larch than for pine plantations established on a similar soil. The differences in N and P inputs were attributed to lower nutrient concentration in pine needle litter compared with larch needle litter, not to total needle litter mass. Annual inputs of nutrient in both plantations were not significantly different among years except for K of the larch although there was yearly different in needlefall mass and nutrient concentration during the 3-year observed period. The results indicate that the mechanisms of litterfall and nutrient inputs vary considerably between pine and larch plantations established on a similar site condition.

• Journal of Ocean Engineering and Technology
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• v.17 no.5 s.54
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• pp.32-38
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• 2003

This study investigates the distribution characteristics and relationship of water quality, and analyzes the spatial and temporal variation and distribution of the pollutant loads at Yeong-il Bay. The results of these analysis, the concentrations of nutrient loads (T-N and T-P), both appeared to be at the maximum value in November, while most small values were taken in May for the T-N, and in August for the T-P. For COD, the maximum concentration was in August, which has much precipitation during the same season, T-N was at the mean, and T-P was at the minimum value. Using the cluster analysis to develop the division of the sea basin by the dendrogram, before and after construction of Pohang New-port, the variation characteristics of water quality of Yeong-il Bay were discussed. The in flowing pollutant loads were transported to the landward by the high-density salinity water volume of the bottom layer therefore, it formed nutrient trap or coastal trapping areas of the pollutant load. By this mechanism, it is clear that the water volume with high-density nutrient exists on both sides of the Pohang New-port. Thus, the sea basins increasing concentration of the pollutant load at Yeong-il Bay are most prevalent at Hyeong-san estuary, the Pohang Old, and New-port. To improve water quality of this sea basin, the reduction of these nutrients loads should be the highest priority.

• Journal of Environmental Science International
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• v.13 no.12
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• pp.1059-1065
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• 2004

Bio sparging experiments were conducted in a laboratory column to investigate the potential removal of diesel contaminated groundwater. The objectives in this study were (a) to determine the extent of diesel degradation in laboratory columns under supplement of nutrient; (b) to determine the effect of variation of air flow in the removal of diesel and (c) to evaluate the potential enhancement of diesel degradation as a function of temperature. Our results showed that the nutrient supplement and higher air flow greatly enhanced diesel degradation. However, the variation of water temperature examined slightly increased degradation rate of diesel fuel.

• Journal of Nutrition and Health
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• v.30 no.3
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• pp.349-359
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• 1997

This study was designed to study sources of variability(subjects, day by day, season, day of week, sequence, number of repeated days, compliance etc.) in multiple 24-hour dietary recall method. Dietary intakes of college women in Seoul were obtained using 24-hour dietary recalls, consecutive 7 days, 4 times for 1 year. The result of this study shows that 1) the reproducibility of multiple 24-hour recalls is low(intraclass correlation coefficient<0.3), 2) the intraindividual variations of all nutrients are more than 80%, 3) the major components of variation are interindividual vriability and intraindividual variability(within person variability and methodologic error). There were small but statistically significant season and compliance effects. 4) the ratio within-person varation to between-person variation for absolute and transformed nutrient intakes except some nutrients such as vitamin A, vitamin C, energy from protein and fat etc, was less than 1.7 the minimum numbers of days needed in 24-hour dietary recalls to estimate usual intake for this group were 1 to 21 days. And the numbers of days needed to get the usual intake of an individual varied among individuals and within individuals for different nutrients, ranged from 1 days for log carbohydrate(% energy) to 470 days for Na. 6) There were greater than 0.7 correlation coefficients between the average nutrient intakes of 12 days and intakes of 28 days. Therefore, it was desirable to take the 24-hour recall more than 12 times, repeating 3 days every season.

• ALGAE
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• v.17 no.4
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• pp.249-257
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• 2002

• Korean Journal of Poultry Science
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• v.47 no.2
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• pp.107-114
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• 2020

This study was conducted to investigate the variation in nutrient composition of oilseed meals and to develop prediction equations for amino acid concentrations. Energy and nutrient contents were determined in a total of 1,380 feed ingredient samples including copra byproducts, corn distillers, dried grains with solubles, palm kernel byproducts, and soybean meal. The ingredient samples were imported to the Republic of Korea between 2006 and 2015. Data were analyzed using the MIXED procedure of SAS. The regression procedure of SAS was used to generate the prediction equation for the lysine concentration using the crude protein (CP) concentration as an independent variable. The concentrations of moisture, gross energy, CP, ether extract, crude fiber, ash, calcium, phosphorus, lysine, methionine, cysteine, and threonine in tested oilseed meals differed (P<0.05) depending on producing countries. The prediction equations for amino acid concentrations (% as-is basis) in the oilseed meals are: lysine = -1.08 + 0.080 × CP (root mean square error = 0.244, R² = 0.924, and P<0.001); threonine = -0.297 + 0.044 × CP (root mean square error = 0.099, R² = 0.958, and P<0.001). In conclusion, energy and nutrient compositions vary in the oilseed meals depending on the producing countries. Moreover, the crude protein concentration can be used as a suitable independent variable for estimating lysine and threonine concentrations in the oilseed meals.

• Particle and aerosol research
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• v.11 no.4
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• pp.115-118
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• 2015

An electrospray patterning method has been considered as a new and effective way for controlling very fine droplets. Drop-on-demand patterning for unstained nutrient broth on wafers was newly conducted with an electrospray pulsed jet. The patterns had been made under varying experimental conditions including flow rate, vibration frequency, and translational speed of the electrospray patterning system. In this experiment, especially, variation of nutrient broth droplet was measured under varying flow rate conditions. This new technique has a potential to be applied in biology experiments and hormone medical industry.

• Korean Journal of Microbiology
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• v.29 no.5
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• pp.329-338
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• 1991

From July 1985 to December 1986, 28 variables of phycal-chemical factors, bacteria and heterotrophic activity were investigated 17 times at 3 stations in the estuary of Naktong River and the influences of environmental factors to bacterial population and heterotrophic activity were analyzed through multiple regression. The results of multiple regression were as follows. At station 1, total bacteria and heterotrophic bacteria(Z-25) could explain 57% of the variation of maximum uptake velocity for glucose and 54% of turnover time for glucose was explained by total coliform bacteria and MBOD, Sixty four percent of the variation of Kt+SN was accounted for salinity, MBOD-N and inorganic phosphate. Turnover rate for acetate was also accounted for the change of MBOD-P by 56%. At station 2 maximum uptake velocity for glucose depends on MBOD-N by 81%; turnover time on bacteria by 50%; Kt+Sn on avilable nutrient by 61%. More than 50% of maximum uptake velocity and turnover time for glucose were influenced by bacteria and that of Kt+Sn by the change of nutrient in the surface water of station 3. In the bottom water of station 3, the change of maximumuptake velocity, turnover time and Kt+Sn for glucose was controlled by total bacteria and available nutrient, bacteria, the change of nutrient salts respectively. On the whole, more than 50% of maximum uptake velocity and turnover time for glucose could be due to the change in the number of bacetria and the value of Kt+Sn was affected by the change of nutrient salts. Turnover rate for acetate was controlled by available phosphate at station 1 and by bacteria at station 2 and 3, which showed a distinct difference between the environmental factors which govern the rate of glucose and acetate uptake in the Naktong esturine ecosystem. And bacterial communities were controlled by available nutrients at station 1, by nutrient salts and salinity at station 2 and in the surface water of station 3 and by salinity in the bottom water of station 3.

• Journal of the Korean Society of Food Culture
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• v.9 no.5
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• pp.447-455
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• 1995

The purpose of the present study is to assess nutrient content for providing nutrition information such as nutrition labeling on Korean dishes in restaurant and food service institutions. The content of nutrients was calculated in recipies used to prepare dishes which has been frequently consumed in such four groups as the literature, foodservice institutions of industries, restaurants, and households. The numbers of dishes surveyed were 15. Total numbers of literture used for recipies analysis are 20. Recipies used in foodservice institutions of industries were abstracted from the journal 'Guk-Min Young-Yang' published in Korea dietetic association and obtained with the help of dietitians working in those institutions. Also, recipies has been using in restaurants were given from the Korea restaurant association. Recipies in households was calculated from the secondary analysis of the Korean National Nutrition Survey. Nutrient content from foods except steamed rice and side dishes in each dish was calculated using data of Korean food composition table published. The content of energy and protein in 'Gal-bi tang' (beef-rib soup) were highest in recipes used at restaurants, vitamin C in recipes of food service institutions of industries due to the generous use of meats and vegetables than other recipies. 'Doen-jang chigae' (soybean paste stew) showed the lowest content of energy in results analyzing recipes presented on the literature and varied protein level by four groups for difference of protein source used. The content of energy in 'Gop-chang jeongol' (small intestines stew) is 150 kcal more than 'Soegogi jeongol' (beef stew) in general. The energy level of 'Daeji-galbi' jim (braised pork ribs) and 'Dak jim' (braised chicken) turned out to be the highest in recipies presented on literature. Variation of each nutrient content including energy and protein was relatively high, since some of foods used in 'Pibimbab' (mixed rice) varied with four groups. Amounts of energy and protein in 'Naeng-myeun' (cold noodles) is the highest in recipies of foodservice institution of industries because much amounts of noodle and meats were used comparing to other groups. The average content of energy in 'Pulgogi' (grilled meat with sauce) was 50% to Korea recommended amounts of one meal, 833.3 kcal. Content of vitamin $B_1$ in 'Jeuk pyeunuk' (boiled pork), which is made of pork meat, was higher than other dishes. The ingredients of frequently consumed Korean dishes were highly variable among the four groups which inevitably results in variation of nutrient content in each dishes. The high variation of nutrient content in each dish according to study requires careful collecting of the large number of recipies in presenting representative nutrient content for nutrition labeling on dishes in restaurant and food service institutions effectively.