• Korean Journal of Environmental Biology
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• v.40 no.1
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• pp.112-123
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• 2022

To assess the influence of environmental factors on the phytoplankton community structure and total phytoplankton biomass during four seasons in 2014, we investigated the abiotic and biotic factors at 25 stations in the Busan coastal region. The phytoplankton community and total phytoplankton biomass were strongly dependent on the discharge from the Nakdong River, and the high density of phytoplankton was related with the introduction of the Tsushima Warm Current (TWC), particularly in the thermohaline fronts of the fall season. The relationship between the salinity and nutrient (Dissolved inorganic nitrogen=DIN: R²=0.72, p<0.001 and Dissolved inorganic silicon=DSi: R²=0.78, p<0.001) highly correlated with the river discharge, implying that those nutrients have played a crucial role in the growth of diatom and cryptophyta. The total phytoplankton biomass was highest in the summer followed by autumn, spring, and winter. Diatom and cryptophyta species were dominant species during the four seasons. Additionally, there were strong positive correlations between Chlorophyll a and total phytoplankton biomass (R²=0.84, p<0.001), cryptophyta (R²=0.76, p<0.001) and diatom (R²=0.50, p<0.001), respectively. In particular, we found that there were significant differences in the nutrients, phytoplankton community compositions, and total phytoplankton biomass between the inner and the outer coastal region of Busan, depending on the amount of river discharge from the Nakdong River, particularly during rainy seasons. Therefore, the seasonal change of TWC and river discharge from the Nakdong River serve an important role in determining phytoplankton population dynamics in the Busan coastal region.

• Journal of the Korean Society for Marine Environment & Energy
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• v.3 no.4
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• pp.23-36
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• 2000

Bottom sea waters in eight stations including from inner bay to outer bay to understand the importance of the submarine groundwater discharge for the environmental assessment of Chinhae Bay was collected in August 1999 and January 2000. Generally, /sup 222/Rn is very useful tracer to assess the submarine groundwater discharge because it is 2-4 orders of magnitude more concentrated in groundwater compared to surface water. The /sup 222/Rn activities ranged between about 33 to 182 dpm/100kg within the bay. Higher activities more than 100 dpm/100kg were found at the inner bay. The /sup 226/Ra activities, its parent, however, were little different between stations. /sup 222/Rn activities at the same station varied with season. It suggests that the major source of /sup 222/Rn is not from the bottom sediment, but from the change of submarine groundwater discharge by precipitation. The contents of Cl/sup -/ and SO/sub 4//sup 2-/ in the groundwater of Wonjeon-ri were very high as 1,312 and 369 ppm, respectively, indicating that this groundwater along the Chinhae coast was affected by seawater. Therefore, the submarine groundwater in the inner Bay may discharge to the overlying water. It indicates that these submarine groundwater discharges may play an important role as another important source of nutrients in the Chinhae Bay, because groundwater around the Chinhae Bay showed high concentration of dissolved inorganic nutrients (average , nitrate>174 μM, silicate>262 μM). Therefore, further studies are required to assess the contribution by the submarine groundwater discharge in the biogeochemical processes of the Chinhae Bay.

• Microbiology and Biotechnology Letters
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• v.33 no.4
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• pp.302-307
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• 2005

The inactivation efficiency of Campylobacter jejuni were assessed in vitro and in vivo using confocal laser microscopy and flow cytometry. C. jejuni cells were inactivated with $1\%$ (w/v) trisodium phosphate (TSP) and the live cells and inactivated cells were distinguished by staining with LIVE/DEAD BacLight Bacteria Viability fluorescent probe. After treatment of TSP for 5 min, most of C. jejuni cells turned to coccoid form from original spiral shape. C. jejuni cells lost total cell viability in the absence of organic nutrients but did not lost total cell viability in the presence of organic nutrients. In vivo test, C. jejuni cells turned to viable but non-culturable (VBNC) form after TSP treatment and remained alive on chicken skin. C. jejuni cells attached on chicken meat would transform to coccoid form by sanitizer treatment, but could possibly be alive by the benefits of organic nutrients present in chicken meat.

• Korean Journal of Environmental Agriculture
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• v.28 no.1
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• pp.32-37
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• 2009

This study was conducted to assess the impact of agricultural land use on the water quality in mountain village farmlands. Two soil types, paddy and upland soil were analysed for their chemical properties. Although, pH and organic matter contents were not significantly different to each other, concentrations of available P and exchangeable K and Ca were much higher in upland soil compared with those in paddy soil. The results of water quality analysis indicated that, in Goseong-cheon watershed, the nutrients contents were much higher in downstream area than in upstream area. Particularly, the elevation of $COD_{Mn}$ and T-P were significant during rainy season. When paddy fields coexist with upland fields, SS, T-N, and T-P concentrations in paddy fields were lower than those of upland fields. This may indicate that paddy fields possess an water-purifying ability by absorbing nutrients. This effect may reduce excessive nutrients discharged into the neighboring streams which may cause eutrophication problem. The difference between inflow and outflow of nitrogen and phosphorus during the cultivation period were measured as -98.9 kg $ha^{-1}$ and -29.7 kg $ha^{-1}$, which means that nutrient outflow was higher than inflow. This may suggest that much nutrient was discharged during the crop harvest period.

• Journal of the Korean Dietetic Association
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• v.9 no.4
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• pp.316-325
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• 2003

This study was carried out to compare the characteristics of the over weight elementary school students with those of desirable-weight children. Anthropometric parameters such as height, weight, BMI, body fat percentile, triceps skin fold thickness were measured. Dietary assessment and blood analysis were performed. The average ages of over weight children and desirable-weight children were 10.9$\pm$2.5 and 10.2$\pm$2.8 years, respectively. The means body fat percentile of over weight children and desirable-weight children were 27.5$\pm$3.7% and 20.2$\pm$3.8%. respectively. Plasma levels of TG, total cholesterol, LDL cholesterol, and HDL cholesterol of over weight children and desirable-weight children were 179.3$\pm$30.0, 104.9$\pm$26.6, 52.3$\pm$6.7 and 178.3$\pm$84.1 mg/dl, and those of desirable-weight children were 86.1$\pm$43.5, 183.7$\pm$16.5, 101.0$\pm$2.1 and 67.7$\pm$20.0 mg/dl, respectively. Plasma TG levels of over weight children were significantly higher than those of desirable weight children. On the other hand, plasma HDL-cholesterol levels of over weight children were significantly lower than those of desirable-weight children. Plasma levels of GOT and GPT were in normal range in both group however, GPT level of over weight children was higher than that of desirable weight children. Plasma levels of albumin, globulin, and BUN were all in normal range and no differences were found in both groups. Hematologic data did not show any difference between two groups except WBC, RBC and Hgb levels which were significantly higher in over weight group than those of desirable-weight children. Daily nutrients intake of over weight children and desirable-weight children were very similar and they were around the Korean RDA levels for each nutrients. However the intake of calcium of both groups were little over 50% of RDA. The consumption of dietary fiber was very low and the cholesterol intake was very high showing that the habitual meals of Korean school children were not well balanced.

• Journal of the Korean Society of Marine Environment & Safety
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• v.28 no.4
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• pp.459-468
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• 2022

Long-term data analyses and bioassay experiments were conducted to assess limiting nutrients in Cheonsu Bay and Taean sea. First, long-term nutrient data (2004-2016) provided by the National Water Quality Monitoring Network were used to assess potential limiting nutrients. Analysis of the long-term data showed that the dissolved inorganic nitrogen/dissolved inorganic phosphate (DIN/DIP) ratio was mostly below 16, with N limitation being dominant. A subsequent analysis using the concentration ratios of N, P, and Si showed that N limitation was dominant during summer and autumn but that Si limitation occasionally occurred during winter and spring in relatively limited areas. However, the dominant limiting nutrient was not determined. The nutrient analysis of the field water collected during the bioassay experiment showed that DIN/DIP revealed P limitation at all stations in March and May, whereas N limitation was dominant in July and October. In the analysis using the concentration ratios of N, P, and Si, P and Si limitation appeared in March and May, but there were points with no dominant limiting nutrient. However, N limitation was dominant in July and October. In the bioassay experiment for assessment of the actual limiting nutrient, the results showed no specific limiting nutrient in March, whereas NH₄⁺ and NO₃^- showed responses in May, July, and October, which confirmed that N was a substantial limiting nutrient directly involved in phytoplankton growth during this period.

• Journal of Nutrition and Health
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• v.45 no.1
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• pp.30-43
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• 2012

Patients undergoing peritoneal dialysis are at risk for protein-energy malnutrition because of nutrient losses during dialysis. This study determined the nutritional status of patients undergoing continuous ambulatory peritoneal dialysis (CAPD). Forty-four patients receiving CAPD were divided into two groups according to dialysis period. We investigated the nutritional status of the patients by measuring anthropometric and biochemical parameters, as well as food intake, self-appetite, dietary habits, a subjective global assessment, and a total nutritional status assessment. Group I subjects (7 males, 13 females) had received dialysis for < 2 years, whereas the group II subjects (18 males, 6 females) received dialysis for ${\geq}$ 2 years. Energy intake with added dextrose in the dialysate per kg of body weight was $30.3{\pm}5.8$ kcal in group I and $29.0{\pm}8.1$ kcal in group II. The average protein intake per kg of weight was $1.0{\pm}0.3$ g in group I and $1.0{\pm}0.4$ g in group II, which were less than the recommended protein intake for patients undergoing CAPD (1.2-1.5 g/kg). Mean serum albumin level was significantly lower in group II than that in group I (p < 0.05). A recent self-appetite score was significantly higher in group II than that in group I (p < 0.01). The dietary habits score was significantly lower in group II than that in group I (p < 0.05). The subjective global assessment was significantly higher in group I (85.0%) than that in group II (54.2%) under normal nutrition status (p < 0.05). The dialysis period was significantly and negatively correlated with the subjective global assessment (r = -0.502, p < 0.01) and the total nutritional status assessment (r = -0.575, p < 0.01). These results demonstrated that patients undergoing CAPD for ${\geq}$ 2 years had worse nutritional status than those who had been undergoing dialysis for < 2 years. Good nutritional status can predict the long-term survival of patients undergoing peritoneal dialysis. Additionally, the exact evaluation of nutritional status before 2 years will be important to maintain long-term dialysis therapy in patients undergoing CAPD.

• Korean Journal of Ecology and Environment
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• v.56 no.1
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• pp.70-82
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• 2023

Recently, Korean government has introduced Multi Metric Indices (MMI) using various biocommunity information for aquatic ecosystem monitoring and ecosystem health assessment at the national level. MMI is a key tool in national ecosystem health assessment programs. The MMI consists of indices that respond to different target environmental factors, including environmental disturbance (e.g. nutrients, hydrological and hydraulic situation of site etc.). We used zooplankton community information collected from Korean lakes to estimate the availability of candidate zooplankton MMI indices that can be used to assess lake ecosystem health. First, we modified the candidate indices proposed by the U.S. EPA to suit Korean conditions. The modified indices were subjected to individual index suitability analysis, correlation analysis with environmental variables, and redundancy analysis among indices, and 19 indices were finally selected. Taxonomic diversity was suggested to be an important indicator for all three taxonomic groups (cladoceran, copepod, rotifer), on the other hand, the indices using biomass for large cladocerans and copepods, while the indices using abundance were suggested for small cladocerans and rotifers.

• 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.

• Nutrition Research and Practice
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• v.4 no.2
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• pp.121-127
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• 2010

Little data exists on metabolic syndrome (MetS) related with intake, especially for the South Korean. The purpose of this study was to develop and evaluate a food frequency questionnaire (FFQ) for nutritional assessment in the population with MetS in South Korea. Randomly selected female participants, mean age 21.9 years (n = 38) were invited to answer the FFQ twice (FFQ1 and FFQ2) over a nine-month interval and to complete twelve-day diet records (DR) during the months between in South Korea. The correlation coefficients for nutrient intake between FFQ1 and FFQ2 varied from 0.253 (niacin) to 0.573 (cholesterol), and the energy intake-adjusted correlation coefficients ranged from 0.187 for protein to 0.662 for iron. The energy intake-adjusted and de-attenuated correlation coefficients for comparison of FFQ1 and the DRs ranged between 0.277 (vitamin $B_1$) and 0.768 (fiber), and between 0.229 (zinc) and 0.859 (fat) for comparison of DRs with FFQ2. The percentages of study subjects classified into the same quartiles in both the DRs and FFQ1 ranged from 15.8% (vitamin $B_6$) to 47.4% (calcium), and for the same quartiles in DRs and FFQ2 from 13.2% (vitamin $B_1$) to 44.7% (potassium). The FFQ has reasonably good validity and reproducibility. Further research is needed for an assessment of reproducibility and validation of present FFQ in the subjects with MetS.