• Journal of Microbiology and Biotechnology
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• v.19 no.12
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• pp.1656-1664
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• 2009

Bioaugmentation of bioreactors focuses on the removal of numerous organics, with little attention typically paid to the maintenance of high and stable nitrite accumulation in partial nitrification. In this study, a bioaugmented membrane bioreactor (MBR) inoculated with enriched ammonia-oxidizing bacteria (AOB) was developed, and the effects of dissolved oxygen (DO) and temperature on the stability of partial nitrification and microbial community structure, in particular on the nitrifying community, were evaluated. The results showed that DO and temperature played the most important roles in the stability of partial nitrification in the bioaugmented MBR. The optimal operation conditions were found at 2-3 mgDO/l and $30^{\circ}C$, achieving 95% ammonia oxidization efficiency and nitrite ratio ($NO_2^-/{NO_x}^-$) of 0.95. High DO (5-6 mg/l) and low temperature ($20^{\circ}C$) had negative impacts on nitrite accumulation, leading to nitrite ratio drop to 0.6. However, the nitrite ratio achieved in the bioaugmented MBR was higher than that in most previous literatures. Denaturing gradient gel electrophoresis (DGGE) and fluorescence in situ hybridization (FISH) were used to provide an insight into the microbial community. It showed that Nitrosomonas-like species as the only detected AOB remained predominant in the bioaugmented MBR all the time, and coexisted with numerous heterotrophic bacteria. The heterotrophic bacteria responsible for mineralizing soluble microbial products (SMP) produced by nitrifiers belonged to the Cytophaga-Flavobacterium-Bacteroides (CFB) group, and $\alpha$-, $\beta$-, and $\gamma$- Proteobacteria. The fraction of AOB ranging from 77% to 54% was much higher than that of nitrite-oxidizing bacteria (0.4-0.9%), which might be the primary cause for the high and stable nitrite accumulation in the bioaugmented MBR.

• Journal of Nutrition and Health
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• v.46 no.1
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• pp.72-85
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• 2013

The purpose of this study was to evaluate trends in the sources of dietary sodium intake in a representative Korean population in the Korea National Health and Nutrition Examination Survey (KNHANES) conducted in 1998, 2001, 2005, 2007, 2008, 2009, and 2010. The study consisted of 53,570 men and women aged 7 years or older participating in the KNHANES during the corresponding years. Overall sodium intake and the mean percent contribution of each dish and food group to dietary sodium intake across 1998-2010 were calculated. The means of sodium intake ranged between 4,572.6-5,498.9 mg/d across 1998-2010. The major dish groups contributing to dietary sodium intake were kimchi (1,154.8-1,521.2 mg/d), noodles and dumplings (505.3-760.5 mg/d), soups (465.3-714.8 mg/d), and stews and casseroles (387.0-579.8 mg/d). The combined mean percent contribution from the top four dish groups contributing to dietary sodium intake showed a slight decrease over the period; 64.4% in 1998, 64.5% in 2001, 59.3% in 2005, 58.2% in 2007, 56.3% in 2008, 56.7% in 2009, and 54.4% in 2010. The major food groups contributing to dietary sodium intake were seasonings (1,852.9-2,435.9 mg/d), vegetables (1,425.6-1,792.1 mg/d), grains (482.2-778.1 mg/d), and fish and shellfish (257.2-351.4 mg/d). In addition, the combined mean percent contribution from the top four food groups showed a slight decrease over the period; 92.8% in 1998, 93.2% in 2001, 93.8% in 2005, 92.1% in 2007, 91.7% in 2008, 90.9% in 2009, and 90.7% in 2010. In summary, we did not observe a reduction in dietary sodium intake over time, however, the percent contributions from the top major dish groups or food groups to dietary sodium intake showed a decrease over the last decade.

• Applied Biological Chemistry
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• v.40 no.4
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• pp.323-328
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• 1997

Runoff of phorate, soil insecticide, were measured under simulated rainfall conditions in field using small test plot$(120\;cm{\times}120\;cm)$ at the loam area and loamy sand area. Fish acute toxicity tests were performed with runoff water to elucidate its toxicological effect on organisms in ecosystem. The average concentrations of phorate in runoff water from loam and loamy sand soil were 11.3 ppb and 4.8 ppb, respectively. However, there was no significant concentration difference between the heavy and the light rain. With loam soil, average runoff rates were 1.31 and 0.18%, while with loamy sand soil those were 0.48 and 0.012% under the heavy and the light rain conditions, respectively. Total average runoff rate was 0.50%. With killifish, no mortality was observed in runoff water from loamy sand soil, whereas half of the population was dead in runoff water from loam soil when it was diluted to 54.4% content.

• Journal of Nutrition and Health
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• v.40 no.1
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• pp.78-88
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• 2007

The purpose of this study was to investigate dietary fat and individual fatty acids intake pattern of 174 college women living in Seoul and Gyong-gi province through internet nutritional assessment system. Each of the subjects was required to input their own food intake for three days, which included two days during the week and one day of the weekend, on the web program directly and all of the data collected were used for statistical analysis. The mean daily caloric intake of the subjects was 1,500.9 kcal which was at 71.5% of Estimated Energy Requirement (EER). Dietary fat contributed 27.6% of the total caloric intake which was slightly higher than the recommended limit of 25%. Daily cholesterol intake was 310.0 mg, which was also high to some degree. Mean daily N6 and N3 fatty acid intake was 6.1 g and 0.9 g, respectively, and calory % calculated from each were 3.63% and 0.53%. This result showed the intake of N3 fatty acid fell in Acceptable Macronutrient Distribution Ranges (AMR) $0.5\sim1.0%$ but that of N6 fatty acid was somewhat lower than the AMDR $4\sim8%$. N6/N3 ratio 8.5/l, however, was within the desirable range $4\sim10/1$. Considering overall dietary fatty acids intake, oleic acid was the most abundant, followed by linoleic and palmitic acid. And among polyunsaturated fatty acids intake, linoleic acid was exclusively high, accounting for 97.4% of total N6 fatty acid intake. On the contrary, three fatty acids, linolenic (67.3%), DHA (21.1%) and EPA (10.0%), together supplied 98.4% of total N3 fatty acid intake. Mean P/M/S was 0.9/l.1/1.0. The subjects' intake of fat, many fatty acids and cholesterol came from diverse food groups including meats, fats and oils, milk and milk products, eggs, fish, and soybean products. Nevertheless, the subjects tended to show unfavorable fat and fatty acids intake pattern in terms of quantity and quality. Based on these results, it is important to monitor dietary fat intake pattern of the general population continuously and an internet program such as the one used for this study would be valuable, especially for assessing dietary patterns in the younger generation.

• Journal of Nutrition and Health
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• v.44 no.2
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• pp.152-161
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• 2011

Koreans have undergone many changes in dietary patterns with economic growth. The purpose of this research was to examine changes in dietary patterns using data from the 1998, 2001, and 2005 Korean National Health and Nutrition Examination Survey. The study included 21,525 subjects (8,295 from 1998, 6,880 from 2001, and 6,350 from 2005) who were 20 years or older and who participated in a 24-h diet recall. The percentage energy intake from 22 food groups was calculated, and a cluster analysis was applied to identify dietary patterns. Two dietary patterns emerged; the first pattern was characterized by high intake of white rice, legumes, vegetables, kimchi, and seaweeds, the so-called "traditional" pattern (53%), whereas the other pattern was characterized by high intake of other grains, noodle dumplings, floured bread, pizza, hamburgers, cereals and snacks, potatoes, sugared sweets, nuts, fruits, meat·its products, eggs, fish, milk and dairy products, oils, beverages and seasoning, or the so-called "modified" pattern. The modified pattern comprised a higher proportion of younger aged, metropolitan residents with more education and higher incomes. However, the gender distribution was not significantly different. The modified pattern had a significantly higher intake of all nutrients except carbohydrates and had a higher proportion of energy from fat and protein. No association with a risk for metabolic syndrome was found for either dietary pattern. After age was standardized, the traditional pattern included 52% of the respondents in 1998, 54% in 2001, and 50% in 2005. However, the modified pattern was significantly more prevalent in the younger age group (20-29 yr), whereas the traditional pattern increased significantly in the older age group (${\geq}$ 65 yr). In conclusion, a secular trend was found for dietary pattern by age group, suggesting that it is necessary to monitor the changes in dietary pattern by age group and to develop appropriate dietary education and guidelines.

• Korean Journal of Fisheries and Aquatic Sciences
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• v.25 no.5
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• pp.331-340
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• 1992

A study on the spawning and fecundity of anchovy, Engraulis japonica, in the southern waters of Korea was carried out on the basis of data collected from gonad examination during March-september, 1991. Spawning period showed that length class in the range of 9-12cm fork length occurred during May-July, whereas adults above 12cm from March to September. In comparison with the oocyte compositions of the ovary of anchovy adult caught at sunrise and sunset, together with variation of the gonad weight and sex ratio of the fish sampled during time between 14:00 and 21:00, considering that the oocyte more than 600um in diameter existed much in the samples from sunset compared with that from sunrise, as well as a decreasing trend in the gonad weight and proportion of female of anchovy taken around sunset, spawning was estimated to occur mainly after sunset. The proportion of the adult with a pronounced peak above 600um in oocyte composition was estimated to be about $20\%$ of the spawning population. Fecundity was estimated to the range of about 23,000-315,000 with batch fecundity of 1,857-8,223 and specific batch fecundity of $438\pm146$.

• Korean Journal of Ichthyology
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• v.7 no.1
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• pp.56-63
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• 1995

Ecological study of the Cynoglossus joyneri was conducted based on the specimens from the western coast of Korea from 1992 to 1994. Ecological characteristics of this species such as gonadal development, occurrence of larvae, stomach contents, and environmental conditions were investigated. Few larvae of Cynoglossus joyneri occurred in Kunsan coast. This coast is influenced by the freshwater input of the Mangyong and Kum River, especially during the summer. Therefore, the larvae of C. joyneri were considered to be spawned and grown during their early life stage in the high saline water in outer bay. Spawning occur from June to September, having the peak spawning period from July to August. Biological minimum size of matured fishes containing mature oocytes is about 143.5mm in total length, which requires about 20 months after hatching. The ranges of total length by age are as follows : 0-ring group(floating stage), 30~70mm ; 1-ring group, 49.0~133.0mm 2-ring group, 128.6~167.0mm ; 3-ring group, 169.0~202.0mm ; 4-ring group, 200.7~240.0mm. The major food items of young fish under 8cm were copepods and invertebrate larvae, and those of adult fishes were annelids(polychaets) in winter, and bivalves and shrimps in summer and autumn. Therefore, it can be assumed that the population of C. joyneri could be reduced due to the decrease of food organisms caused by the continuous reclamation activities in the inner bays of the west coast of Korea.

• Korean journal of applied entomology
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• v.48 no.1
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• pp.87-94
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• 2009

KNI3126 which is the eco-friendly material made by plant extracts - neem and matrine - have been evaluated for efficacies against 6 main pests and toxicity on natural enemies. Insecticidal efficacies of KNI3126 against plant hopper were above 95% at 5 days after treatment (DAT), whereas pesticidal effects against the cotton aphid were above 95% at 3 DAT and slightly decreased at 5 DAT. Insecticidal efficacy against the palm thrips resulted in lower control value as 68.1% than that of chemical insecticides. KNI3126 showed more than 95% control value against diamond back moth, suggesting that it could suppress the population of pest hard to control as eco-friendly material. Mortalities against two-spotted spider mite were about 80% at 1 DAT and over 90% at 5 DAT, respectively. For evaluation of the toxicity on natural enemies, effect against predatory natural enemy was classified as moderate selective toxicity based on the criterion of International Organization of Bio-Control (IOBC), whereas against parasitic natural enemies was found to be relatively safe. Repellent effect was weak against plant hopper, but strong against two-spotted spider mite. In the toxicity test for safety, KNI3126 was classified as the lowest level at acute oral, acute dermal and fish toxicity test and did not induce the irritancy at skin irritation test and eye irritation test.

• Korean Journal of Environmental Biology
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• v.30 no.4
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• pp.355-361
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• 2012

Genus of Gambierdiscus, Ostrepsis, Prorocentrum, Coolia and Amphidinium are epiphytic ciguatoxin-producing armored dinoflagellate, often attached on macroalgae. These organisms are the primary causative agent of ciguatera fish poisoning which occurs in tropical and subtropical regions. However, regardless of the fact that population of epiphytic dinoflagellates have expanded to such temperate areas from sub-trophic and trophic areas, monitoring of the epiphytic dinoflagellates was greatly lacked in coastal water of Korean Peninsula. This study was performed in the Korean Peninsula in November, 2011. Cell densities of Gambierdiscus spp. on macroalgae ranged from zero to 10 cells $g^{-1}$ and the maximum density was recorded at St.18 (Pohang guryongpo). The abundance of Ostreopsis spp. was highest on macro-algaes Chondrus ocellatus, Lomentaria catenata and Plocamium telfairiae (140 cells $g^{-1}$). The maximum abundance of Prorocentrum, Coolia and Amphidinium were 52, 3 and 1 cells $g^{-1}$, respectively. Of these, Prorocentrum lima was observed at most stations of East Sea. Therefore, our results suggest that the epiphytic armored dinoflagellates may have adapted to Korean coastal water of temperate areas (i.e., East Sea) and those abundances may be related to the macroalgal species.

• Asian Pacific Journal of Cancer Prevention
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• v.16 no.12
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• pp.5125-5135
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• 2015

Background: Total fat intake may be associated with increased risk of breast cancer, and fish oil has been suggested as a protection factor to breast cancer. But the effect of vegetable oils is inconclusive. We aimed to investigate the association with high vegetable oils consumption and breast cancer risk, and evaluated their dose-response relationship. Design: We systematically searched the MEDLINE, EMBASE, Cochrane databases, and CNKI updated to December 2014, and identified all observational studies providing quantitative estimates between breast cancer risk and different vegetable oils consumption. Fixed or random effect models were used to estimate summary odds ratios for the highest vs. lowest intake, and dose-response relationship was assessed by restricted cubic spline model and generalized least-squares trend (GLST) model. Results: Five prospective cohort studies and 11 retrospective case-control studies, involving 11,161 breast cancer events from more than 150,000 females, met the inclusion criteria. Compared with the lowest vegetable oils consumption, higher intake didn't increased the risk of breast cancer with pooled OR of 0.88 (95% CIs:0.77-1.01), and the result from dose-response analyses didn't show a significant positive or negative trend on the breast cancer risk for each 10g vegetable oil/day increment (OR=0.98, 95% CIs: 0.95-1.01). In the subgroup analyses, the oils might impact on females with different strata of BMI. Higher olive oil intake showed a protective effect against breast cancer with OR of 0.74 (95% CIs: 0.60-0.92), which was not significant among the three cohort studies. Conclusions: This meta-analyses suggested that higher intake of vegetable oils is not associated with the higher risk of breast cancer. Olive oil might be a protective factor for the cancer occurrence among case-control studies and from the whole. Recall bias and imbalance in study location and vegetable oils subtypes shouldn't be ignored. More prospective cohort studies are required to confirm the interaction of the impact of vegetable oils on different population and various cancer characteristic, and further investigate the relationship between different subtype oils and breast cancer.