• Journal of Wetlands Research
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• v.13 no.3
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• pp.643-655
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• 2011

This study addresses the periphytons along the Bukhan river stream and examines the biological indices that represents the river and estimate water quality assessment. Bukhan river in 4 major watershed streams (Bukchon-Hangeychon, Narinchon, Inbukchon, and Soyang river) was selected in 9 points. Land use pattern along the streams showed marked differenced in agriculture areas and forest areas. Lower Soyang streams showed blue-green algae and green algae also appeared in evenly pattern. Thus, the pollution source, biomass and distribution are somewhat correlated, and BOD, SS, biodiversity, and evenness showed a similar pattern. This situation can lead to conclusion of oligotrophic lake with good condition. Therefore, current biological index and is not so desirable for stream degree standard water quality and nutrient level.

• Journal of Environmental Science International
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• v.20 no.10
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• pp.1243-1263
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• 2011

This study was carried out to determine marine environments and phytoplankton community in Deukryang Bay during the period of summer in 1987-2010. Water temperature, salinity, pH and dissolved oxygen were shown in much yearly fluctuations. In August, water temperatures in surface and on bottom were the highest, compared with average surface (24.54$^{\circ}C$) and bottom (22.90$^{\circ}C$) water temperature for 18 years in Deukryang Bay. The main reason is assumed to longer duration of sunshine during the period of August. Although the amount of the rainfall in August was the highest, significant impact of marine environment did not show. Most of dissolved inorganic nitrogen and phosphate in Deukryang were lower concentration during summer and N:P ratio also showed below 18 in Redfield. In particular, extreme increasing of N:P ratio in August was occurred by intensive precipitation. Distribution of phytoplankton community was a consistent occurrence for 18 years. The genus of Chaetoceros, Cosinodisucs and Skeletonema were regarded as the represent diatom, whereas the highest occurrence of genus among dinofagellates was Ceratium. It is thought that the relationship between phytoplankton and nutrient has a strong positive signal, although nutrients persist a little concentration and much fluctuations in marine environments were observed. High availability in phytoplankton is contributed to consistently provide the food organism of shellfish. Consequently, recent decreasing production of shellfish and seed are probably associated with higher temperature during the period of summer. However, higher temperature is also occurred ago and after 2000. On the basis of geography, Deukryang Bay had a small mouth and long channel, which is attributed to decreasing genetic diversity. It is assumed that higher temperature and lower genetic diversity have a extreme impact of larvae and shellfish for reproduction in Deukryang. It is necessary to persistently monitor based on water quality and phytoplankton community.

• Korean Journal of Community Nutrition
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• v.17 no.3
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• pp.302-311
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• 2012

The purpose of this study was to provide preliminary data for better safety control over children's preference foods sold in school stores. The survey was conducted from June to July 2009, to collect 749 types of children's preference foods sold in 150 middle and high school stores nation-wide excluding Jeju Island and general and nutrition information were analyzed. Out of 749 types of snack food items, 689 and 602 snacks were sold at high school and middle school stores respectively. Among children's preference foods, cookies, bread, and ice-cream were the main items. Among them, 98% of snacks were domestic products and the price range of each individual snacks were mostly between 600 and 900 won. 27.8% of children's preference foods sold were found to be in the high calorie/low nutrition food group. Even though the proportion of candy and fruit/vegetable beverages sold were not high, their proportion in high calorie/low nutrition snack group were higher than 68.1%. Among the children's preference foods sold in middle and high school stores, carbonated drinks and ramen were continuously sold in certain middle and high schools, even though sales were prohibited. This study concludes that government, corporations and retailers should work together in developing healthier children's snack distribution environment. In addition, dairy products, which take up 15% of children's preference food, should be diversified to meet their nutrient requirements.

• KOREAN JOURNAL OF CROP SCIENCE
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• v.31 no.4
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• pp.493-498
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• 1986

In order to evaluate the effect of various cultural methods developed during last 30 years on grain yield of wheat and barley and structure of plant stand for uptake of nutrient and water, solar energy use and com-petitive capacity with weed, 10 kinds of cultural practices were compared in the clayey upland soil. Row fertilization is more effective for uptake of N,P and K than rotary fertilization. Weed occurrence was deeply related with width of non-seeded area in the row and affected yield decrease. Winter injury was more serious in the cultural practices with thick plant community than in those with isolated individual plant. Root distribution was more remarkable in drill seeding or broadcasting than row seeding and had positively correlated with water consumption of barley.

• KOREAN JOURNAL OF CROP SCIENCE
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• v.52 no.2
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• pp.220-227
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• 2007

Sweetpotato fields in Korea are highly infected with virus and virus like diseases that greatly diminish both yield and quality as indicated by field observations and laboratory tests. In order to solve this problem, there is an urgent need to produce and mass propagate virus-free planting materials for distribution to the farmers. These experiments were conducted, firstly, to determine the most appropriate culture media, nutrient solution, and cutting intervals to maintain growth and vigor of tissue cultured plantleta as mother plants for propagation in insect-proof greenhouse. And as a labor saving method, the production efficiency of plug trays for rapid propagation of stem cuttings as a source of planting materials was likewise evaluated. Results showed that plants grown in medium B supplied with 0.5 and 1.0 strength of MS nutrients had high growth rate, and 20-day cutting interval was the best. 72-plug tray was better than 128-plug. Secondly, it was to develop a technique for the production of first-generation seed roots using hydroponics cultivation system. The yield of virus-free plants propagated in the non-insect proof and open-field cultivation was 2,402 kg/10a, 6% higher than those in the insect-proof cultivation, and the rate of virus re-infection was 18% higher compared to 3.3% with insect-proof cultivation. Lastly, it was to investigate the growth performance of virus free plants in farmers' field. Differences were existed in the yield depending on the variety used, but virus free plants showed an increase of $6{\sim}24%$ over virus infected plants.

• Ocean and Polar Research
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• v.32 no.1
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• pp.1-13
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• 2010

To assess short-term variation of summer phytoplankton community structure in different water masses, phytoplankton and environmental factors were monitored from 31 stations on and off the southern coasts of Korea, from June 18 to June 20 2009. According to multidimensional scaling (MDS) and cluster analysis based on phytoplankton community data from each station, the southern sea was divided into two groups. The first group included stations in the south-eastern region of Jeju Island, which is strongly influenced by the Kuroshio warm current. The second group located along the coastal region of the southern sea, which was mainly comprised of Bacillariophyceae and Crytophyceae. Of these stations, St. 13 and 28 formed a temperature front caused by different hydrological conditions. In particular, nutrients and Chl.a concentrations in these two stations were significantly higher compared to those in the other stations. This indicates that phytoplankton population and subsequent microalgal growth under high nutrient concentrations vary in different water masses. Our results support the theory that phytoplankton community structure in the southern sea of Korea can be influenced on a short-term scale by different water masses and currents.

• Journal of Nutrition and Health
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• v.31 no.4
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• pp.777-786
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• 1998

The purpose of this study to investigate the relationship between nutrient intake and serum lipid levels in 165 healthy women in Taegu. A convenient method was to assess nutritional intake. Anthropometric measurement of body weight and height were measured and average energy expenditure calculated . The mean body mass index (BMI) was 23.4$\pm$3.1 and it was higher than the mean BMI of Korean women. Obesity rates for the study subjects were 15.7% by RBW (relative body weight : >120%) and 28.5% by BMI(body mass index) ; >25). Daily energy intake was sufficient at 106% of recommended dietary allowances and the energy percentage ration of carbohydrate , fat and protein was 68 : 18 : 14. Mean intake of vitamin A, B1 , niacin , and Ca were higher than RDA. The incidence of hypertension(>140mmHg) and hypercholoesterolemia(>240mg/dl) as 18.2% and 23.6% of the subjects, respectively . Postmenopasusal women showed significantly higher blood pressure, RBW, and ALP (alkaline phosphatase) than premenopausal women. The concentration of cholesterol and average blood pressure in the irregular meal eater group were significantly higher than in the regular meal eater group. Skipping meals and unenvendurnal distribution(no breakfast, or no lunch , and large evening meals) are associated with high total cholesterol level in this population . Especially, the atherogenic index was significantly lower in the regular meal eater group than that in irregular meal eaters. The values for serum cholesterol, triglyceride, blood pressure, BMI, and atherogenic index increased with age in middle-aged women. There was a highly significant correlation between body weight and plasma lipids. HDL -cholesterol was inversely correlated with BMI. The above dta provides valuable information for community program planning and health providers who work with individual female and adults to meet their nutrietional needs to control blood lipids.

• Journal of Nutrition and Health
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• v.31 no.9
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• pp.1422-1432
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• 1998

This study investigated the nutritional status of 32 CAPD patients. Their weight, height, triceps, mid arm circumference were measured and their dietary intake and the blood profiles were evaluated. They were 56.0${\pm}$11.8 years old. Their intake of energy and protein were 78% and 93% of RDA respectively. The energy from dextrose was 376.1${\pm}$83.2kcal. The men's and women's intake of protein was 84.6% and 102.1% of RDA respectively, According to the distribution of BMI, 23.5% of the men and 6.1% of the women were underweight and 5.9% of the men and 20% of the women were overweight. The serum albumin levels of the men and women were 3.30 and 3.71g/41 respectively. However, the average amount of serum ferritin, as a whole, comes within the normal range, which shows that stored iron was not decreased and that their anemia was not caused by iron deficiency. The subjects were divided into three groups according to the level of albumin, and their intakes of nutrients were compared with one another, The group with the high level of albumin showed that energy and protein intake was significantly larger and that BMI was also significantly higher than the other groups. There was a positive correlation between BMI and energy intake. Serum total protein had a positive correlation to energy intake ; hematocrit, to carbohydrate intake. BMI had a positive correlation to energy intake. A relative magnitude of factors affecting albumin level was analyzed by Stepwise multiple regression analysis. Overall results about relative influence of independent variables to dependent variable(albumin) indicated that the blood total protein(p <0.0001) was the most significantly correlated with serum albumin level in all subjects,1311owe4 by creatinine and total cholesterol. (Korean J Nutrition 31(9) : 1422-1432, 1998)

• Korean Journal of Veterinary Research
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• v.26 no.1
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• pp.97-102
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• 1986

The prevalence of diarrhea caused by enterotoxigenic Escherichia coli was surveyed on 445 calves in 6 farms which were located in the central part of Korea. The incidence of enterotoxigenic Escherichia coli in calves with diarrhea was investigated by detecting the K99 and F41 antigens from the isolated strains of Escherichia coli The incidence of colibacillosis in calves was 23.3%. Of 238 strains of Escherichia coli isolated from calves with diarrhea, 73 strains(30.6%) were proved possessing the K99 antigen by mannose-resistant hemagglutination(MRHA) using horse red blood cells and 79(33.1%) possessing F41 antigens by MRHA using guinea-pig red blood cells. The minca medium, nutrient broth, tryptic soy broth and brain heart infusion were tested for yield of K99 and F41 pili. The production of pili was greatest in minea medium. The best detachment method of the K99 and F41 pili from the cells was heat treatment for 20 minutes at $60^{\circ}C$ and concentration by precipitation with ammonium sulfate. The purified antigens of K99 and F41 were polypeptides with molecular weights of 18,500 and 29,500, respectively by sodium dodecyl sulfate-polyacrylamide gel electrophoresis.

• Korean Journal of Soil Science and Fertilizer
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• v.49 no.4
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• pp.327-334
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• 2016

In order to compare phosphorus (P) behavior of livestock manure compost (LMC) and chemical fertilizer (CF) applied to the sea-reclaimed land soils, incubation experiments were conducted for five weeks. Four soils differing textural classes, sandy loam and clay loam, and electric conductivity (EC) value, high and low, were applied with CF and LMC. LMC was applied at the level of 0, 1, 2, and 3% on the soil weight basis and CF was applied at the same levels of P as LMC. The results showed that increase of P application rate of CF and LMC led to linearly increase available $P_2O_5$ and $0.01M\;CaCl_2$ extractable P contents regardless of soil texture and EC. However, 0.01M $CaCl_2$ extractable P from soil applied with CF was significantly higher than with LMC. Correlation analysis between $0.01M-CaCl_2$ extractable P and fractionated P by different extraction methods showed that $0.01M-CaCl_2$ extractable P positively correlated with KCl-P (soluble and exchangeable P) and HCl-P (Ca and Mg bound P). However, NaOH-P (Fe and Al bound P and organic P) and residual P was adverse. The amount of NaOH-P significantly influenced to the amount of 0.01M $CaCl_2$ extractable P of CF and LMC in the soils. The application of LMC at sandy loam soil could be carried out in the consideration of nutrient leaching and crop uptake.