• Korean Journal of Ecology and Environment
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• v.35 no.3 s.99
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• pp.160-171
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• 2002

The impact of summer monsoon on water quality of the lower Nakdong River was evaluated during the summer (June-August) in 1997. Several limnological variables were measured in the interval of $1{\sim}3$ day using an automatic monitoring system (Hydrolab $Recorder^{TM}$) to detect water quality changes caused by rainfall on onehour basis. During the monsoon period (from late June to mid July), 5 times of major rainfall events of >50 mm were recorded in the river basin. Dynamic changes of water quality were observed during the monsoon, and the first rainfall event (June$25{\sim}27$) had a significant influence on the water quality at the lower part of the river. All Parameters were largely changed due to the first rain event, and the changed level was maintained until the end of monsoon period. Nutrient concentrations and turbidity increased and values of the other parameters were declined as a result of water dilution. This rainfall event, Changma, is a meteorological phenomenon caused by the East-Asian monsoon climate. The magnitude and frequency of the rainfall during the early monsoon play an important role in change of water quality and ecosystem characteristics of large river systems.

• Korean Journal of Food Science and Technology
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• v.46 no.3
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• pp.334-340
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• 2014

Toxin-producing Bacillus cereus is the causative agent of two different types of food poisoning: the emetic and the diarrheal types. This study was conducted to investigate the presence of enterotoxin and emetic toxin genes in 263 B. cereus isolated from 619 different ready-to-eat food items. Hemolytic enterotoxins hblA, hblC, and hblD were detected in 85.6, 41.1, and 76.8%, respectively, of the B. cereus isolates. About 67.0% (175/263) of the isolates presented all of three genes. Non-hemolytic enterotoxins nheA, nheB, and nheC were detected in 100, 97.0, and 68.4% of the isolates, respectively. Approximately 90.0% (236/263) of the isolates presented all of these three non-hemolytic enterotoxin genes. Emetic toxin gene, CER, was detected in 132 of 263 (50.2%) isolates. Computer-assisted cluster analysis of Rep-PCR profiles showed a high genetic diversity among the isolates. All B. cereus isolates from food samples tested in this study carried at least 6 of 10 toxin genes.

• Korean Journal of Food Science and Technology
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• v.45 no.1
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• pp.59-69
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• 2013

This study investigated the frequency, amount and consumption patterns of 50 potentially hazardous foods (PHF) along with consumers' risk perceptions towards PHF in Korea. A quantitative survey was performed from May through August by trained interviewers, surveying 1,000 adults aged over 18 who were randomly selected from six major provinces in Korea. Consumers perceived seafood, including shellfish, mussel, sashimi and sushi, as the top foods with the highest risk, followed by raw sliced beef. The food with the highest frequency intake per month was leafy vegetables, which is used to wrap other foods, followed by blanched vegetables, fried chicken, etc. The group of middle aged individuals with economic stability had the highest frequency intake of sashimi and sushi. Respondents living in small regions consume greater PHF portions at once. Food safety education with regard to the risk of PHF is essential for consumers, with high frequent intake of PHF.

• Korean Journal of Food Science and Technology
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• v.48 no.5
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• pp.399-404
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• 2016

The applicability of photostimulated-luminescence (PSL) and thermoluminescence (TL) for the detection of 12 food materials (potato, onion, garlic, dried pumpkin, black mushroom, black soybean, Cheongkukjang powder, sea mustard, pepper powder, Ramyun soup, corn tea, and green tea powder) irradiated with an electron beam, gamma ray, and X ray at a range of 0.15 to 10 kGy was investigated. For PSL, negative results (less than 700 photon counts (PCs)) were observed from non-irradiated foods while the irradiated foods showed intermediate (879 to 2,414 PCs) and/or positive (19,951 to 65,919,035 PCs) values. In all irradiated samples, the maximum peak of the TL glow curve was observed between 150 and $250^{\circ}C$. Our findings demonstrate the successful application of PSL and TL to determine whether food items were irradiated or not. However, there were no significant differences among the radiation sources.

• Korean Journal of Food Science and Technology
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• v.30 no.4
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• pp.976-982
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• 1998

The effects of the glycoprotein (PAG) isolated from Pteridium aquilinum on the immune function was examined in mice. PAG was intraperitoneally administered into BALB/C mice for 14 days and the antibody forming ability to hen egg lysozyme (HEL) and the blastogenic responses of splenocytes were measured. PAG treatment significantly increased antibody formation to HEL in a dose-dependent manner. Blatogenesis of splenocytes in response to lipopolysaccharide (LPS, B-cell specific mitogen) or phytohemagglutinin (PHA, T-cell specific mitogen) was also increased after treatment with PAG, indicating that the PAG increases both humoral and cellular immunities. To examine whether the immune function of PAG was via a direct effect on the lymphocytes, splenocytes were isolated from BALB/C mice, exposed to various concentrations of PAG in vitro and the blastogenic responses were measured. In vitro exposure to PAG significantly increased blastogenesis of splenocytes to LPS up to $500{\;}{\mu}g/kg$, whereas the blastogenic response to PHA was not altered by PAG treatment. To identify the fraction responsible for the increase in the immune function, the effect of periodate digest, pronase digest or purified polysaccharide on the antibody production to HEL was examined. Crude protein fraction of PAG significantly increased the antibody formation to HEL. On the other hand, both crude and purified polysaccharide fractions did not have any effects on the antibody production ability. These data indicated that 1) PAG increased both humoral and cellular immune functions, 2) the increase in humoral immunity was probably via a direct action of PAG on lymphocytes and 3) the protein portion of PAG was responsible for the increase in humoral immunity.

• Journal of the Korean Society of Food Culture
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• v.11 no.4
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• pp.487-495
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• 1996

The consumer perception on health and food habit, the experience of health food use and the discrimination between health food and drug of Korean consumer were surveyed by using a questionnaire containing 20 items in order to obtain the basic data for the assessment of the benefit and risk of health foods in Korea. A total of 1,000 people over 20 years of age living in Seoul and the vicinities were interviewed and asked to fill out the questionnaire during the period from the October 1995 to the February 1996. Among the 882 answers collected 23 was incomplete data, and 859 answers were used for the statistical analysis by using SAS program. The survey revealed a strong interest of the consumer on health food by showing that more than a half of the subjects (58.8%) had the experience of actual use of health food, and 68.2% believed the effectiveness. What the consumer expect most from health food was to have beneficial effect to maintain overall health condition (59.8%), and the most negative aspect of health food was the overstatement on the effectiveness by the producers (52.1%). The most important source of information for the purchase of health food was the suggestion of friends and relatives (30.6%). Among the health foods registered and regulated by the food law, royal jelly (22.7%), squalene (16.0%), refined fish oil (15.1%), lactic acid bacteria (10.6%) and aloe (8.8%) were relatively well aware. Although 84% of the subjects perceived that health food is different from drug or traditional medicine, the largest percentage of the subject selected ginseng as the most well known type of health food (22.7%) as well as the most well known drug (or traditional medicine) (41.7%). Ginseng was also chosen as the most frequently used health food (17.0%), and vitamin tablets the third (13.0%). The vague definition of health food and unambiguous discrimination of it from medicine by the consumers were problematic for the correct use and reasonable purchasing behavior. The clear definition and proper regulation on the manufacture and distribution of health food, more strict control of labelling and advertisement, and a wide consumer education on health food were recommended.

• Restorative Dentistry and Endodontics
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• v.36 no.1
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• pp.37-49
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• 2011

Objectives: The aim of this study was to evaluate the surface color of indirect resin restoration according to the layering placement of different shade of incisal composite. Materials and Methods: In this study, CIE $L^*a^*b^*$ value of 16 Body composite of Tescera ATL (Bisco, Schaumburg IL,USA) was measured by spectrophotometer (NF999, Nippon Denshuku, Japan), and compared to CIE $L^*a^*b^*$ value of Vitapan shade guide. Nine shade Incisal composite of Tescera ATL were buildup to 1 mm thickness on Body composites inlay block, and CIE $L^*a^*b^*$ value was measured. Incisal composite was ground to 0.5 mm thickness and CIE $L^*a^*b^*$ value was re-measured. Color difference between Body composite and Incisal composites layered on Body composite was calculated as a function of thickness. Results: Color difference between corresponding shade of Tescera Body composite and Vitapan shade guide was from 6.88 to 12.80. $L^*$ and $b^*$ value was decreased as layering thickness of Incisal composite on Body composite was increased. But, $a^*$ value did not show specific change tendency. Conclusions: Surface color difference between Body composites and Incisal composites layered on Body composite was increased as the layering thickness of Incisal composite increased (p < 0.05).

• Journal of the Korean Society of Food Science and Nutrition
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• v.30 no.5
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• pp.894-899
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• 2001

Intakes and excretions of zinc and copper were determined for 8 female adolescents (aged 16.4$\pm$0.5 y; body mass index 20.4$\pm$1.3kg/$m^2$; body fat 33.3$\pm$2.5%; bone mineral density of lumbar spine in L2-L4; 0.96$\pm$0.08g/$\textrm{cm}^2$) when they consumed diets basal and high in calcium for 6 days each. All subjects consumed a basal Ca diet containing 800 mg, Korean RDA level of the subjects, and a high Ca diet containing 1200mg, RDA plus 2 SDs of calcium intake. The diets provided 58% of energy intake as carbohydrate, 25% as fat, and 17% as protein. Food, urine and fecal samples were collected during the last 3 days of each feeding period and were assayed. Mean daily intakes on the basal and high calcium diets, respectively, were 6.57 and 6.37 mg for zinc and 910 and 812 $\mu\textrm{g}$for copper. Fecal excretion of copper and zinc in relation to intake was significantly greater on the high calcium than on the basal calcium diet. Hence, apparent absorption rate was significantly lowered from 98.7% on the basal calcium diet to 97.9% on the high calcium diet for zinc from 66.3% to 56.4% for copper, respectively. Urinary loss of copper was not detectable but that of zinc was 0.38mg on the basal diet and 0.47mg on the high calcium diet. Copper retention was 899$\pm$105$\mu\textrm{g}$/day on the basal calcium diet and 792$\pm$20.8$\mu\textrm{g}$/day on the high calcium diet, and zinc retention was 3.95$\pm$0.91mg/day and 3.11$\pm$0.89mg/day. Thus, copper and zinc retention was significantly decreased on the high calcium diet (p<0.05). Summarizing the results, apparent absorption and retention of zinc and copper were significantly decreased by calcium supplementation. Therefore, it is suggested that interactions among minerals should be considered in determining RDA.

• Journal of the Korean Society of Food Science and Nutrition
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• v.45 no.3
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• pp.409-419
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• 2016

The objective of this study was to investigate dietary sodium sources at the dish level in 228 university students (71 men, 157 women) in Gyeonggi-do. Daily sodium intake was estimated from a validated 125-dish frequency questionnaire. In men, body mass index, systolic blood pressure, and sodium intake were significantly higher than in women. Men showed higher sodium intake from soups, fish or shellfish dishes, meat dishes, and soybean dishes than women. The dishes that most largely contributed to daily sodium intake were Napa cabbage kimchi and ramen in both men and women. In addition, relatively higher amounts of sodium from ramen were consumed in men, whereas cookies were the 5th highest sodium source in women. In both men and women, the high sodium intake groups consumed more sodium from kimchi, dishes cooked with kimchi, dishes with broth, and salted mackerel than the low sodium intake group. There were significant differences in major dishes contributing to between-person sodium intake variations between men and women. Short rib soup for men and Korean sausage for women were the largest contributors to sodium variations, which are common dishes served with salt. Men consumed more drinks and also more sodium from drinks than women. In conclusion, there were significant differences in major dishes contributing to absolute and between-person sodium intake variations in university students between men and women. Further studies on effects of gender on blood pressure, sodium and drink intake, and obesity are necessary.

• Journal of Yeungnam Medical Science
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• v.18 no.1
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• pp.75-84
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• 2001

Background: The accidental swallowing of foreign body is a common problem in the children. Ingested foreign bodies may be managed by endoscopy, observation, or surgery. So we analyzed the methods of removal, type, location and complications of foreign bodies. Materials and Methods: This report reviewed 37 cases of ingested foreign body in the gastrointestinal tract at the Department of Pediatrics, Yeungnam University Hospital between January 1997 and April 2001. Results: The age ranged from 8 months to 8 years. The most prevalent age group was between 1 year and 2 years of age(19%). The male to female ratio was 2.1:1 with 25 male and 12 female patients. The type of foreign bodies were coins in 20 cases(54%), nail in 4 cases(11%), key in 4 cases(11%), pin in 2 cases(5.5%), necklace in 2 cases(5.5%) and others. The locations of foreign bodies were upper esophagus in 12 cases(32.5%), lower esophagus in 4 cases(10.8%), stomach in 16 cases(43.2%), small bowel in 5 cases(13.5%). 4. Presenting symptoms were variable with asymptomatic(59.4%), vomiting(19.0%), epigastric pain(8.1%), dysphagia(5.4%) and others. The methods for removal of foreign bodies included 20 cases of endoscopic removal(54.0%). 3 cases of spontaneous removal(8.1%) and there was no surgical removal. 14 cases(37.9%) did not confirmed removal of foreign body because of no revisit of our hospital. Endoscopic finding of patients were normal(15 cases), ulceration(2 cases), erosion(1 case), inflammation(1 case), mucosal scratch(1 case). Conclusion: It appears that the endoscopic approach is the preferable method for the removal of upper gastrointestinal foreign bodies in the children.