• KOREAN JOURNAL OF CROP SCIENCE
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• v.46 no.3
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• pp.253-259
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• 2001

The purpose of this study was loused on understanding of uptake of nutrients by plants, the behaviors of nutrients in soil and the possibility of leaching loss when N fertilizer (urea) and mature compost were applied. Lysimeters (volume 0.15㎥, diameter 62cm, height 62.8cm) were installed for collecting leachate in the Jeju volcanic ash soils. Lysimeter study consisted of thirteen treatments: fellow, fellow with weeding, cropping without fertilizer and compost, three N fertilizer soil surface applications (16, 32, and 64 kg/10a), three N fertilizer and compost soil surface applications (16+800i 32+1600, and 64+3200 kg/10a), two water dissolved N fertilizer applications(16 and 32 kg/10a), and low and high plant densities. The growth of corn (preceding crop) and potatoes (succeeding crop) and leaching loss were determined during the experimental period. The amount of leachate from lysimeter was remarkably greater at bare conditions than at cropping conditions for corn and potatoes. The N content of plants (corn and potatoes) tended to increase as fertilizer rate increased. Fertilization of urea dissolved in water to soil was more efficient than surface fertilization for the growth, yield, and the N uptake N of corn and potatoes. There were no differences in dry matter yield of plants between medium and high N rates, but N, Ca, K and Mg concentrations of plants were higher at higher N rates. There were significant correlations between N uptake and each of Ca, K and Mg uptakes in corn and potatoes. Total N uptake by plants increased with increased N fertilizer and compost applications. Plane absorbed 54.9% of applied N at low N rate and 31.0 to 34.0% at high N rates. The proportion of N leaching losses was lower at low N rate and high plant density.

• Journal of Nutrition and Health
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• v.21 no.5
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• pp.305-316
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• 1988

The purpose of this research was to determine the relationship of the dietary nutrients to blood pressure among preschool children in Seoul and to concurrently study the effect of seasonal variance on the aforementioned relationship. The subjects of the study consisted of 203 preschool children aged four to six years. Anthropometric measurements of height, weight, pulse rate and blood pressure, urinary excretion of five cations(Na, K, Ca, P, Mg), creatinine and urea nitrogen and dietary questionaires concerning sodium, potassium calcium and phosphorus were taken during the two periods of summer(Aug. 1986)and winter(Feb, 1987). The results obtained are summarized as follows: 1) The daily urinary excretion of five cations, creatinine and urea nitrogen is summer and winter was as follows; The sodium content was 57.8 mEq in the summer and 59.4 mEq in the winter ; potassium 20.4 mEq and 23.0 mEq, respectively ; calcium, 5.5 mEq and 3.6 mEq, respectively ; and phosphorus, 27.4 mEq and 19.9 mEq, respectively. Only calcium and phosphours excretions in the urine showed significant differences per season(p<0.05). 2) The average dietary intake per day of sodium was 2349mg in the summer and 2155mg in the winter ; potassium consumption was 1425mg in the summer and 1448mg in the winter ; intake of calcium was 472mg in the summer and 500mg in the winter ; and phosphours consumption was 642mg in the summer and 634mg in hte winter. The sodium-to-potassium consumption ratio 1.6 and 1.5, respectively, in the summer and in the winter and the calcium-to-phosphorus ration was 0.7 in the summer and 0.8 in the winter. The dietary calcium intake showed significant differences between the seasons. 3) The principal source of sodium consumption among preschool children was from seasoning-including talbe salt, soy sauce and instant sauce-which accounted for higher then 45% of the sodium intake in both seasons. The main source of potassium was frutis and vegetables which accounted for 29.6% of the potassium intake in the summer and 25.7% in the winter. Milk and milk products were the primary dource of calcium(higher then 40% in both seasons) 4) In the summer, urinary phosphours levels were weakly reated to systolic blood pressures. (0.05

• Asian-Australasian Journal of Animal Sciences
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• v.14 no.9
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• pp.1282-1289
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• 2001

One feeding trial and two metabolic trials were conducted to investigate the effects of lysine to protein ratio in practical swine diets on growth performance and efficiency of nitrogen retention and utilization in different growing phases. In Trial one (the feeding trial), 90 mixed sex pigs weighing $9.1{\pm}1.4kg$ (Duroc ${\times}$ Landrance ${\times}$ Beijing Black) were used to study the effects of concentrations of 5.2, 5.3, 5.8, 6.4 and 7.2 g lysine/100 g CP in diets containing 1.2% lysine on growth performance and serum urea nitrogen. The results showed that feed conversion efficiency and economic efficiency were best for pigs fed the diet containing the lysine concentration of 5.8 g /100 g crude protein. Serum urea nitrogen concentration decreased linearly (p=0.0009) and serum free lysine content increased linearly (p=0.0017) as the lysine to protein ratio in diets increased from 5.2 to 7.2 g/100 g. In Trials two and three (the metabolic trials), five growing barrows (Duroc ${\times}$ Landrance ${\times}$ Beijing black), with initial body weights of approximately $26{\pm}2.4kg$ and $56.3{\pm}3.5kg$, respectively, were allotted to five dietary treatments according to a $5{\times}5$ Latin square design. Trial two contained 5.2, 5.7, 6.1, 6.7 and 6.8 g lysine/100 g CP treatments. Trial three contained 4.6, 5.0, 5.6, 6.1 and 6.6 g lysine/100 g CP treatments. The results showed that nitrogen retention in growing pigs decreased linearly (p=0.0011 in Trial two; p=0.0099 in Trial three) as the lysine to protein ratio in diets increased. The ratio of lysine to protein in diets resulting in maximum nitrogen retention was 5.2 g/100 g and 5.0 g/100 g in Trial two and Trial three, respectively. In Trial two, apparent biological value and gross nitrogen efficiency increased linearly (p=0.0135 and p=0.0192, respectively) as the lysine to protein ratio increased from 5.2 to 6.8 g lysine/100 g CP. In summary, we concluded that the optimal Lysine to Protein Ratios for 8-20 kg and 20-80 kg pigs were 5.8 g/100 g and 5.0 to 5.2 g/100 g, respectively.

• Journal of the Korean Society of Food Science and Nutrition
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• v.16 no.3
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• pp.1-10
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• 1987

For surveying of constituents concerning the flavor of the dried tomato fruits, nonvolatile components such as minerals, sugars, free amino acids, nucleotides and lipids were analyzed and determined. Potassium, calcium and phosphorus were the major conatituents of ashes, but trace amounts of cadmium and lead were determined. Glucose and fructose were the major constituents in sugars, and the latter slightly showed higher value than the former. The content of total free amino acids was 8322.5mg%, and that of the major components such as asparagine, aspartic acid, urea. glutamic acid, ${\beta}-alanine$ and ${\gamma}-aminobuthyric$acid showed 58.01% to the total amount. The nucleotides were composed of CMP, UMP, GMP and IMP, and CMP among them showed the highest value as about 58.07% to the total amount. On the other hand, IMP showed the lowest one. The major components of the total fatty acids from the saponifiable fraction in the lipids were $C_{18:2}$, $C_{18:1}$ and $C_{16:0}$ and those of the total sterols from unsaponifiable one were stigmasterol and ${\beta}-sitosterol$.

• Journal of Adhesion and Interface
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• v.9 no.1
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• pp.28-34
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• 2008

This study was used particleboard with urea-formaldehyde resin and cross linking vinyl resin. Manufactured particleboard had high cross linking vinyl resin content that internal bonding strength was low value but flexural strength was increased. For emission test of particleboard using VOC Analyzer, it was confirmed that more cross linking vinyl resin had reduced 4 volatile organic compounds (Toluene, Ethylbenzen, Xylene, Styrene) but also TVOC (Total VOC), 5 VOCs (Benzene, Toluene, Ethylbenzen, Xylene, Styrene) and formaldehyde emissions from manufactured particleboard were also lower emission factor than particleboard with only urea formaldehyde resin.

• Korean Journal of Soil Science and Fertilizer
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• v.27 no.1
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• pp.40-47
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• 1994

The objective of this research was to examine the effect of ammonium thiosulfate(ATS) on urease activity and on biological and chemical properties of flooded paddy soil especially having high organic matter content by comparing with the effect of sodium thiosulfate(STS). The results obtained are summarized as follows. 1. The hydrolysis of urea was inhibited at 3 and 5 days after treatment of thiosulfate(ATS and STS) +glucose and thiosulfate only, respectively. The inhibitory effect of ATS on urea hydrolysis was slightly lower than that of STS in glusoce-added soils, but when the glucose was not added, the effects of ATS and STS were not different significantly. 2. The soil pH and Eh was lowered by 0.3~0.5 units and 30~120 mV, respectively, when incubated flooded soil with ATS and glucose at $25^{\circ}C$. 3. Soil respiration rate in/flooded soil was increased by 10~70% with the treatment of ATS during the 20 day experimental period. 4. The contents of acetic and butyric acid in thiosulfate treatment soil was below $10{\mu}g/g$, which was lower than that($220.3{\mu}g/g$) of critical growth inhibition of rice.

• Korean Journal of Food Science and Technology
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• v.32 no.5
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• pp.991-996
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• 2000

Enzyme-linked immunosorbent assay was developed for the analysis of soy protein in foods. Competitive indirect ELISA (ciELISA) was established by using specific antibodies against the heat-stable acidic subunits (AS) of glycinin. Soy proteins in each sample used in this study were solublized in the presence of urea and DTT and boiled at $100^{\circ}C$ for 1hr and then were renatured with a cystine-containing solution. After these treatments, each isolated soy protein (ISP) heated at 60, 70, 80, $90^{\circ}C$ for 10 minutes showed almost the same curve as unheated one in the ciELISA. The detection limit of ISP was 0.3 ${\mu}g/mL$. Anti-AS antibodies have very low reactivities less than 0.1% toward non-meat proteins such as skim milk and casein and did not show any reactivities toward egg white powder and ovalbumin. When laboratory-made sausages containing ISP of $0.5{\sim}3%$ were assayed by ciELISA, the mean recovery was about 83% (C.V., 19%). In addition, the average content of soy protein in commercial sausages was 1.27%.

• Journal of the Korean Wood Science and Technology
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• v.45 no.5
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• pp.599-612
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• 2017

Human hair (HH) is produced as a waste from beauty parlor and barbershop. HH-based adhesives were formulated with NaOH-hydrolyzed HH, $H_2SO_4$-hydrolyzed chicken blood (CB) and PF as a crosslinking agent. Physicochemical properties and retention rate against hot water of the adhesives were measured to investigate the potential of HH as a raw material of wood adhesives. HH was composed of keratin-type protein of 80% and over. Ash of less than 0.1% was contained in HH. Among the amino acids included in HH, glutamic acid showed the highest content, followed by cysteine, serine, arginine and threonine. Solid content of the adhesives ranged from 33.2% to 41.8% depending on hydrolysis conditions of HH and PF type. Viscosity at $25^{\circ}C$ ranged from 300 to $600mPa{\cdot}s$ resulting in a sprayable adhesive. Retention rate against hot water measured to evaluate the water resistance of adhesives was the highest in the cured resin formulated with 5% NaOH-hydrolyzed HH and 5% $H_2SO_4$-hydrolyzed CB. Meanwhile, the molar ratio of formaldehyde to phenol in PF did not have a significant impact on the retention rate of HH-based adhesives. When the retention rates of HH-based adhesives were compared to those of conventional wood adhesive resins used for the production of wood-based panels extensively, HH-based adhesives formulated with 30 wt% PF showed lower retention rate than commercial urea-formaldehyde resin. However, when PF content was increased to 35 wt%, the retention rate greatly increased and approached to that of commercial melamine-urea-formaldehyde resin. Except for the results mentioned above, the analysis of economic feasibility suggests that HH-based adhesives can be used for the production of wood-based panels if HH is hydrolyzed in proper conditions and then the HH-based adhesives are formulated by the HH hydrolyzates with 35 wt% PF.

• Microbiology and Biotechnology Letters
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• v.17 no.6
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• pp.568-573
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• 1989

As a way to determine the optimal culture conditions for the production of ${\gamma}$-linolenic acid by Mucor sp. KCTC 8405P, the influence of different carbon and nitrogen sources, initial pH, and C/N ratio of medium was investigated. Glucose was found to be the best carbon source in terms of lipid content and ${\gamma}$-linolenic acid yield. Ammonium sulfate and organic nitrogen sources such as urea and peptone resulted in relatively increased lipid and ${\gamma}$-linolenic acid production. The highest accumulation of lipid was obtained at a C/N ratio of 56.6 using glucose and (NH$_4$)$_2$SO$_4$ as carbon and nitrogen source, respectively. It was found that the lipid content increased significantly with increasing initial pH of medium up to pH 9.0. The influence of mixed carbon source on the ${\gamma}$-linolenic acid yield was also investigated. High accumulation of lipids, 315 mg/100 ml medium, and 13-14% of ${\gamma}$-linolenic acid content in the cellular lipid were obtained in a shaking culture containing 3% of glucose and 2% sodium acetate as carbon source and 0.1% of (NH$_4$)$_2$SO$_4$ as nitrogen source at pH 8.0.

• Food Science and Preservation
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• v.22 no.4
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• pp.598-606
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• 2015

To develop a functional drink using abalone, two abalone composites (APM-1, APM-2) were prepared by mixing the abalone and natural plants (Lycii fructus and Rubus coreanus Miq.). Their antioxidant and anti-fatigue effects were evaluated using rats running on a treadmill after 4 weeks supplementation of the abalone composites. Experimental groups were divided into four groups including normal (non-exercised group), control (exercised group), one dose per day (EAPM-1), and three doses per day (EAPM-2) with exercise by running. Antioxidant activities, and total phenols and flavonoids contents of APM-2 were significantly higher than those of APM-1 (p<0.05). Total lipid content in serum of EAPM-2 was significantly lower than that of control group (p<0.05). Lactate dehydrogenase activity and blood urea nitrogen content of EAPM-1 and EAPM-2 groups were significantly lower than that of control group. There were no significant difference in aspartate aminotransferase activity among control, EAPM-1 and EAPM-2 groups. In the meanwhile, alanine aminotransferase and alkaline phosphatase activities were significantly lower than that of control group. In serum and liver tissues of EAPM-1 and EAPM-2 groups, lipid peroxide contents significantly decreased compared to control group. DPPH radical scavenging activities in liver tissues of EAPM-1 and EAPM-2 groups were significantly higher than those of control group. Therefore, abalone composites were effective for the alleviation of oxidative stress caused by treadmill running, which was dependent on antioxidant activity and phenolic compounds content.