• Journal of Food Hygiene and Safety
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• v.35 no.3
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• pp.225-233
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• 2020

By the standards and specifications for hygiene products, three test methods for formaldehyde are specified for each item type of hygiene product. After derivatization using acetylacetone and 2,4-dinitrophenylhydrazine (2,4-DNPH), formaldehyde is analyzed by spectrophotometer and high-performance liquid chromatography (HPLC). Validation of the three test methods was performed on tissue, diaper lining and waterproof layer, and panty liner products. The results of linearity (R²), limit of detection (LOD), limit of quantification (LOQ), recovery rate (%) and reproducibility (%), showed that all three methods are suitable for analyzing formaldehyde in hygiene products. After derivatization with 2,4-DNPH and cetylacetone, formaldehyde was analyzed at 0, 3, 6, 9, 24 and 48 hours by HPLC. Formaldehyde derivatized with 2,4-DNPH showed no statistically significant change in formaldehyde peak area over time (P>0.05). But, acetylacetone-derivatizated formaldehyde showed a negative correlation coefficient (r) over time (P<0.01). We investigated the residual amounts of formaldehyde in 205 hygiene products distributed in Busan. Among 74 disposable diaper products tested, 73 had low concentrations of formaldehyde (0.13-29.87 mg/kg). Moreover, formaldehyde was not detected in any of 78 tissue, 27 disposable paper towel, 12 disposable dishcloth, 7 paper cup, one brand of paper straw and 6 disposable napkin products.

• Journal of Preventive Medicine and Public Health
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• v.21 no.1 s.23
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• pp.183-194
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• 1988

This study was carried out to investigate for resistance of V. parahaemolyticus that isolated from patients of food poisoning and fish and shellfish, captured in east coast of Kyungpook province of Korea from 1985 to 1986. VP ATCC 17802 and NAG V. ATCC 6538 were used as control. In fish, shellfish and seaweed, the more temperature increased, the shorter survival time was. In case of sea-water, the more temperature rose up, the longer survival time was, particularly in $37^{\circ}C$ and $25^{\circ}C$, the strains had survived after 6 months. And in tapwater, it was sterilized in 150 mins. and survived for 11.5 days on maximum in ground water. In kimchi, at room temperature, germicidal time was shorter more than 6 times compared with that which had been kept in refrigerator. It survived for 57.1 days in milk, 49.2 mins. in yougurt. Strains had been surviving in frozen condition at $-70^{\circ}C$ even after 6 months, present study time. In resistance test in water bath at several degrees of temperature, all the strains were sterilized in 20 mins. with $60^{\circ}C$. In resistance test to driness, number of surviving strains dropped rapidly in 10-11%) water contents. In UV $2538{\AA}$, strains were sterilized in 20 mins. In resistance test to alcohol, strains had survived for 0.1-4 mins. in fermentative wine of below than 25% and distilled wine of over than 25% in alcohol concentration. The bactericidal concentration of disinfectant was 1% in phenol and 3% in cresol. In 0.1M acetic acid and 0.1M lactic acid, number of surviving colonies decreased rapidly but not in citric acid. The more NaCl concentration rose up, the lower decreasing rate of number of surviving colonies was. The strains had showed sensitive response to vancomycin, chloramphenicol, gentamicin, and resisted to carbenicillin, ampicillin and kanamycin. When one day culture strain was cultured till 25th day, resistant strains to tetracycline and cephalothin were changed to sensitive.

• Korean Journal of Medicinal Crop Science
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• v.11 no.3
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• pp.246-251
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• 2003

Angiotensin converting enzyme(ACE) belongs to the class of zinc protease and plays an important role in the regulation of blood pressure. In this experiment, we investigated the inhibitory activities of ninety four plant extracts on ACE. The extracts were prepared by water and refluxing with 70% and 100% methanol. Among the extracts, two plant extracts such as Cassia tora, Persicaria cochinchinensis Kitagawa showed more than 60% inhibitory activities, and Foeniculum vulgare Gaertner, Scutellaria baicalensis Georgl, Caragana sinica (Buchoz) Rehder, Inula britannica var. chinensis showed $45.2{\sim}49.7%$ inhibitory activities. Twenty eight plant extracts such as Hemerocallis fulva L, Camptotheca acuminata Decne, Inula britannica var. chinensis, Xanthium strumarium, Polygonatum odoratum, Phellodendron amurense Rupr, Coix lachryma-jobi var. mayuen, Prunus ansu, Hibiscus mutabilis L, Thchosanthes kirilowii, Helianthus annuus, Juglans sinensis showed $30.3{\sim}39.7%$ Inhibitory activities. These results suggest that plant extracts which contain high ACE inhibitory activities may be useful as anti-hypertension agents and to the treatment of hypertension.

• Journal of the Korean Society of Food Science and Nutrition
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• v.39 no.11
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• pp.1611-1618
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• 2010

This study was conducted to evaluate the effects of Eriobotrya japonica and Saurus chinensis extracts and their fermented extracts on immune parameters in BALB/c mice treated with 1% 2,4-dinitrochlorobenzene (DNCB). The groups were Eriobotrya japonica extract (BI), Saurus chinensis extract (SA), mixture with E. japonica extract and S. chinensis extract (FB) and fermented mixture with E. japonica extract and S. chinensis extract (FA) and distilled water treated control. The level of serum immunoglobulin (Ig) E was decreased in FA compared to control group, but significant difference was not observed (p<0.05). The histamine and contents in FA and control group were $1.47{\pm}0.20$ ng/mL and $1.90{\pm}0.04$ ng/mL, respectively (p<0.05). Ceramide contents were significantly increased in FA compared to BI, SA, FB and control group (p<0.05). These results suggest that FA supplementation in the DNCB treated BALB/c mice affect anti-allergic activities positively, and may be used as functional material for suppression of atopy dermatitis in food industry.

• Journal of Institute of Control, Robotics and Systems
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• v.7 no.9
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• pp.717-722
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• 2001

This paper presents a methodology on the backward path tracking control of a trailer type robot which consists of two parts: a tractor and a trailer. It is difficult to control the motion of a trailer vehicle since its dynamics is non-holonomic. Therefore, in this paper, the modeling and parameter estimation of the system using a real-coded genetic algorithm(RCGA) is proposed and a backward path tracking control algorithm is then obtained based on the linearized model. Experimental results verify the effectiveness of the proposed method.

• Korean Journal of Fisheries and Aquatic Sciences
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• v.34 no.5
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• pp.445-456
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• 2001

In the 1990s, Cochlodinium polykikoides red tide has been annually occurred in the southern coast of Korea and caused the mass damage to the fisheries with a huge amount of economic loss. The present study was done to establish the biological foundation for the elucidation of the mechanism of C. polykikoiaes red tide. The growth response of C. polykikoides to physico-chemical factors such as temperature, salinity, pH, and light intensity were examined using axenic cultures to evaluate the relative importance of these factors on the dynamics of natural populations, It was found that the highest growth conditions were $25^{\circ}C,\;40\%_{\circ}$, pH 7.5, and 7,500 lux, respectively. The tolerable salinity range of growth was relatively wide at an optimum temperature and was reduced to a much narrower range at a sub-optimum temperature. These findings indicate that C. polykikoides is an eurythermal and euryhaline organism. The organism demanded higher light intensity and oceanic pH narrow in its growth. C. polykikoides utilize inorganic nutrients, such as nitrate and ammonium as N, and phosphate as P. The nutritional requirements of C. polykikoides were $40{\mu}M$ for nitrate, $50{\mu}M$ for ammonium, and $5{\mu}M$ for phosphate. The half saturation constant (Ks) for growth was $2.10{\mu}M$ for nitrate, $1.03{\mu}M$ for ammonium, and $0.57{\mu}M$ for phosphate. These values were comparatively smaller than those of other dinoflagellates reported previously. We confirmed that the organism is characterized as an eutrophic species. However, ammonium Ks value is smaller than that of other eutrophic species, This result indicates that C. polykikoides red tide may outbreak in the waters which eutrophication is in progress rather than eutrophicated waters. C. polykikoides preferred ammonium better than nitrate as a nitrogen source when in a growth stage, Therefore, our results indicate that ammonium is more important nutrient on the growth of the organism in comparison with other inorganic nutrients and C. polykikoides red tide is related with the increased ammonium concentration in the coastal waters.

• Clinical and Experimental Pediatrics
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• v.51 no.7
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• pp.754-759
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• 2008

Purpose : Abnormal activation patterns of Th1/Th2-cells have been suggested to increase the prevalence of allergic diseases. Prevention is regarded as an important corner stone in the management of allergic diseases. In this study, we have investigated the relationship between cord blood levels of IL-4, IL-10, and IL-12 in preterm newborns and the development of allergic respiratory diseases in infancy Methods : Forty-six preterm newborns born at the Ewha Womans University Mokdong Hospital between January 2003 and July 2005, were enrolled for this study, and consent was obtained to test their cord blood samples. Clinical history was obtained from the hospital records. Cord blood was obtained at birth and kept frozen until it was tested. The levels of IL-4, IL-10, and IL-12 were determined by enzyme-linked immunosorbent assay (ELISA). Results : All infants were followed-up for a median of $16.0months{\pm}13.2d$ (range, 12.0 to 36.0 months). Eighteen infants who developed wheezing showed lower cord blood levels of IL-12 ($366.60{\pm}140.40$ vs $435.09{\pm}91.20pg/mL$, P=0.009). Cord blood levels of IL-4 and IL-10 showed no significant difference between the two groups. Four newborns who later developed asthma, and infants with asthma showed lower IL-12 level in the cord blood than other groups. Conclusion : Lower concentration of cord blood levels of IL-12 in newborns who later developed wheezing and asthma suggested that they had abnormal activation patterns of Th1/Th2-cells at the time of birth, and cord blood IL-12 level can be used as a predictor of allergic respiratory diseases.

• Korean Journal of Poultry Science
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• v.13 no.1
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• pp.41-48
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• 1986

In order to investigate the storage period of packed chicken meat in relation to the bacterial contamination of each processing part, a special grade poultry processing plant located at Dongdoochun-City, Gyeonggi-Do, was surveyed mainly in point of sanitary conditions. The results are summarized as follows. 1. processing room near reception and packing room next to shipping area showed the highest bacterial counts in air. 2. Equipments and instruments for slaughtering also showed a high degree of bacterial contamination even before the operation. This finding suggested that the possibility of the bacterial contamination of carcasses through equipments and instruments would be high, if the continuous sanitary control measures are not properly taken. 3. The bacterial count of scalding water was 3${\times}$10$\^$7/ for standard plate count and 4${\times}$10$\^$5/ for most probable number of coliform bacteria at 1 hour after the start of operation. These values were maintained until the completion of processing. 4. At the ending of chilling process, the bacterial counts of chilling water were 3.3 ${\times}$10$^4$ and 3.0${\times}$10$^3$for standard plate count, when the volume of water used per bird were 21 and 51, respectively. Bacterial contamination was further decreased about 10$\^$-3/-10$\^$-4/ times as the effective chlorine concentration in chilling water was maintained about 50 ppm. 5. An average standard plate count of the residual water In abdominal cavity of carcasses was 3.9${\times}$10$^4$immediate after chilling, however, it increased to 4.7${\times}$10$\^$7/ when the carcasses were packed and stored for 10 days at 4$^{\circ}C$. off-odour development was observed as the bacterial count was not less than 10$\^$6//$m\ell$ of the residual water of the packed carcasses. Data indicated that if the standard plate count of the residual water in abdominal cavity of carcasses was not less than l0$^4$immediate after chilling, the packed chicken meat would not be stored longer than 5 days at 4$^{\circ}C$.

• Korean Journal of Soil Science and Fertilizer
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• v.9 no.2
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• pp.77-81
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• 1976

On a newly reclaimed acidic soil, investigation was made to find out the influence of lime and phosphorus application by a large quantity on the uptake of zinc by corn and its distribution in leaves and stem, under a factorial combination with two levels of zinc, lime, and phosphorus with three kinds of soil texture. The results are summarized as following, 1. The concentration of zinc in stem reflected the zinc uptake status of corn better than the leaves. The concentration of zinc in stem responded clearly to the treatments of lime and zinc, while those of leaves tended to be constant regardless of the application of lime and zinc. 2. The zinc uptake was not improved by compost application though it increased the yield of corn significantly. 3. The application of lime for neutralization of soil with low level of phosphorus application affected the yield of dry matter differently among different soils, slight increase on sandy loam soil, slight decrease on loam soil, and significant decrease on clay loam soil. The yield decrease on clay soil is considered to be due to the decreased availability of applied phosphorus owing to the large amount of lime applied.

• Korean Journal of Soil Science and Fertilizer
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• v.11 no.1
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• pp.43-50
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• 1978

In order to compare the effectiveness of different phosphorus forms (pulverized as regranulized) and formulars (compound fertilizers) of fused phosphate and to compare the effectiveness of boron from different forms (straight borax, granulized with fused phosphate and included in compound fertilizer), a field experiment was conducted on a relatively fertile upland soil using soybean as a test crop. Results are summarized as following. 1. Yield of soybean was significantly higher in the plots fertilized with P when compared to check plot (no p). However, no significant differences were observed among the different forms or formulars of fused phosphate, indicating that the regranulization or formulation of compound fertilizer did not influence the effectiveness of phosphorus. 2. The application of boron, regardless of its formular, brought about higher B content in plant tissue and higher grain yield. There was a tendency that boron contained in ragranulized fused phosphate was more effective than straight borax. The results also indicated that when boron is to be included in NPK compound fertilizer, its content should be at the least 1.5% as $B_2O_3$. 3. The effectiveness of boron appeared as increased number of pod, higher B, and Ca contents in plant and the amounts of uptake of these elements by soybean. 4. The analysis of soil after the experiment indicated that different forms or formulars of fused phosphate were similarly effective in increasing the available P, Ca, and Mg contents in the soil. 5. Slight increase in available B contents in the experimental plot soils applied with boron fertilizer was observed after the trial.