• Korean Journal of Soil Science and Fertilizer
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• v.29 no.4
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• pp.424-431
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• 1996

This study was carried out to provide information for establishing counter measures of soil pollution through analysis of Cd. Cu, Pb, and Zn in paddy soils and brown rice. Cadmium, Cu, Pb, and Zn contents in soils were analyzed and distribution maps for these heavy metals were prepared. Heavy metal contents in brown rice were also measured. Average contents of Cd, Cu, Pb, and Zn in surface paddy soils extracted with 0.1 N HCl were 7.4, 35.8, 98.9, and $118.8mg\;kg^{-1}$, respectively. These were 9 times (Cu) to 50 times (Cd) higher than the background level of heavy metals in unpolluted paddy soils in Korea. The contents of Pb and Zn were lower than those measured in 1980, whereas Cd content did not decrease. The levels of heavy metal contamination in paddy soils may not affect growth or yield of rice plant, however, Cd contents indicated a level of serious concern to humans. The average contents of Cd, Cu, Pb, and Zn in brown rice were 0.38, 2.38, 1.31 and $22.31mg\;kg^{-1}$, respectively.

• Food Science and Preservation
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• v.19 no.1
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• pp.62-66
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• 2012

With the rapid growth of fresh-cut produce market, the South Korean fresh-cut industry is facing the challenge of ensuring food safety. As the estimation of the microbial numbers in fresh-cut produce processing lines (tools, and equipment) using the conventional microbiological techniques takes days, so there is a need for faster and easier monitoring methods. This study was conducted to investigate the use of ATP bioluminescence assay to measure the degree of microbial contamination from three actual fresh-cut processing lines. The samples collected from frech-cut vegetables, and fresh-cut fruits processing plants were tested for the estimation of the bacterial number, using the ATP bioluminescence and microbiological methods. The result of former was transferred to log RLU/100 $cm^2$, and that of the latter was transferred to log CFU/100 $cm^2$. A positive linear correlation between the ATP bioluminescence assay value and aerobic-plate count was found for fresh-cut processing lines, with a correlation coefficient of 0.8772 (n=50). The results of this study indicate that ATP bioluminescence assay can be used to monitor microbial contamination in fresh-cut produce processing plants, and can help improve the hygiene therein.

• Journal of the East Asian Society of Dietary Life
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• v.23 no.5
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• pp.654-661
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• 2013

The current research is designed to analyze sterilization effects on mulberries in terms of storage temperature and storage period after treating with tap water (TW), electrolyzed water (EW) and aqueous chlorine dioxide ($ClO_2$). The treated $ClO_2$ concentrations are 10, 50, 100 and 200 ppm. In each concentration, the mulberries are soaked for 30 seconds respectively. The sterilization effects are being compared at room temperature ($25^{\circ}C$) and at $4^{\circ}C$, respectively. And the enzyme activity related to quality is also being investigated and analyzed about for browning inhibition effects. Microbial sterilizing power increases more in treating plots with EW and $ClO_2$ than treating plot with TW. Futhermore sterilizing power of $ClO_2$ increased sharply on high concentration treatment plot as well. Sterilization effects of $ClO_2$ during storage time are better at cold temperature. Pictures taken from scanning electron microscope reveal that there are no microbes in sterilizing solutions treatment plots. From measurement of the enzyme activity, it is concluded that activities decrease more in sterilizing solutions treatment plots as comparing with TW treated plot during the time. The amount of total polyphenolics decrease with the time passing and EW and $ClO_2$ treatment shows less contents than TW treatment. Thus, EW and $ClO_2$ treatment of mulberris are considered as method to improve safety by reducing total plate count and to contribute to quality maintenance and to extend storage time.

• Journal of the Korean Society of Food Science and Nutrition
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• v.41 no.9
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• pp.1191-1196
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• 2012

The purpose of this study was to investigate the tyrosinase, xanthine oxidase, angiotensin converting enzyme (ACE) inhibitory effects, and nitrite scavenging abilities of Jubak (alcohol filter cake, AFC) hot water and ethanol extracts. Tyrosinase inhibitory effects of Jubak hot water and ethanol extracts were above 85%. Nitrite scavenging ability was higher at pH 1.2 than at pH 4.2 and 6.0. Nitrite scavenging abilities of water and ethanol extracts were above 90% at pH 1.2. Xanthine oxidase inhibitory effect of Jubak hot water and ethanol extracts showed a lower, and the effect did not different by hot water and ethanol. ACE inhibitory effects of Jubak hot water and ethanol extracts were approximately 43~53% and 36~47%, respectively. Overall, our results indicate that Jubak hot water and ethanol extracts may have tyrosinase and ACE inhibitory effects and nitrite scavenging ability, but no xanthine oxidase inhibitory effect. Therefore, Jubak has potential as a cosmetic raw material. Additionally, Jubak could be used as a food additive.

• Journal of the Korean GEO-environmental Society
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• v.21 no.10
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• pp.11-16
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• 2020

Korea's agricultural reservoir is one of the country's major infrastructures and plays an important role in people's lives. However, aging reservoirs are a risk for life and property. Currently, large and small dams and reservoirs have been constructed nationwide for more than 40 years of aging. Dams and reservoirs built nationwide are managed by various institutions. Therefore, it is difficult to manage all dams and reservoirs due to cost and time. Managers in the field with less management personnel and lack of expertise should be able to quickly identify risk factors for multiple reservoirs. In this study, risk factors such as seepage, leakage, settlement slide, crack and erosion were selected. To assess the risk of the items, we used the analytical hierarchical process (AHP), one of the Multi-Criteria Decision Making (MCDM) methods. The analysis showed that seepage has the greatest impact on reservoir collapse. It is judged that the priority of detailed diagnosis can be determined by evaluating the risk of dam reservoir collapse in a convenient way in advance using the calculated weight.

• Korean journal of applied entomology
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• v.43 no.3 s.136
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• pp.211-215
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• 2004

Temperature-fecundity of the melon aphid, Aphis gossypii Glover, was studied at constant temperatures ranging from 15 to $32.5^{\circ}C$ under $60-70\%$ RH and a photoperiod of 16 : 8 (L : D) A life table parameters were constructed using the results. The longevity of A. gossypii gradually increased with decreasing temperature below $27.5^{\circ}C$. Also fecundity increased with decreasing temperature and the highest fecundity was 61.8 nymphs per female at $17.5^{\circ}C$. However. daily fecundity increased with increasing temperatures up to $22.5^{\circ}C$ showing 5.9 nymphs per day and thereafter decreased. Longevity and fecundity of the adult in the greenhouse with an average temperature of $21^{\circ}C$ and $65.6\%$ RH, were 20.0 days and 59.6, respectively, which were longer and higher than those in the growth chamber with similar conditions. net reproductive rate (Ro) was 54.9 at $17.5^{\circ}C$ while intrinsic rate of increase ($r_m$) and finite rate of increase ($\lambda$) were the highest 0.5 and 1.6 at $30^{\circ}C$, respectively. doubling time (DT) and mean generation time (T) were the shortest 1.4 and 6.8 at $30^{\circ}C$ indicating that optimal temperature for the development is $30^{\circ}C$.

• Korean journal of applied entomology
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• v.43 no.4 s.137
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• pp.305-310
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• 2004

The development of Myzus persicae (Sulzer) was studied at temperatures ranging from 15 to $32.5^{\circ}C$ under $70{\pm}5\%$ RH, and a photoperiod of 16:8 (L:D). Mortality of 1st-2nd nymph was higher than that of 3rd-4th nymph at the most temperature ranges whereas at high temperature of $32.5^{\circ}C$, more 3-4nymph stage individuals died. The total developmental time ranged from 12.4 days at $15^{\circ}C$ to 4.9 days at $27.5^{\circ}C$, suggesting that higher the temperature, faster the development. However, at higher end temperature ranges of 30 and $32.5^{\circ}C$, the development took 5.0 and 6.3 days, respectively. The lower developmental threshold temperature and effective accumulative temperatures for the total immature stage were $4.9^{\circ}C$ and 116.5 day-degrees. The nonlinear shape of temperature related development was well described by the modified Sharpe and DeMichele model. When the normalized cumulative frequency distributions of developmental times for each life stage were fitted to the three-parameter Weibull function, attendance of shortened developmental times was apparent with pre-nymph, post-nymph, and total nymph stages in descending order. The coefficient of determination $r^2$ ranged between 0.87 and 0.94.

• Korean journal of applied entomology
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• v.57 no.3
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• pp.165-175
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• 2018

Insects are known to live at wide range of temperature, but can not survive when they are exposed to over $40^{\circ}C$ or below supercooling point. The larvae of Helicoverpa assulta have been reared at high ($35^{\circ}C$), low (3 to $10^{\circ}C$), and room temperature ($25^{\circ}C$; control). To identify stress-related genes, the transcriptomes of fat body have been analyzed. Genes such as cuticular proteins, fatty acyl ${\Delta}9$ desaturase and glycerol 3 phosphate dehydrogenase were up-regulated whereas chitin synthase, catalase, and UDP-glycosyltransferase were down-regulated at low temperature. Superoxide dismutase, metallothionein 2, phosphoenolpyruvate carboxykinase and trehalose transporter have been up-regulated at high temperature. In addition, expressions of heat shock protein and glutathione peroxidase were increased at high temperature, but decreased at low temperature. These temperature-specific expressed genes can be available as markers for climate change of insect pests.

• Journal of agricultural medicine and community health
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• v.40 no.4
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• pp.240-249
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• 2015

Objectives: Farmers are known to be exposed to a variety of allergens related to the work environment. This study was conducted to determine the sensitization rates as well as South Korea that they are sensitized to certain allergens farmers through the skin prick test. Methods: By targeting a total of 1143 people living in the rural town of Gyeonggi Province, it was conducted a questionnaire containing demographic and occupational risk factors and underwent skin prick tests with 15 types of allergens(including positive and negative controls). Multivariable logistic regression analysis was used to analyze the association between occupational risk factors and skin prick test positivity. Results: Except for the 30 people whose result is invalid, positive rate of the skin prick test was 18.6% in 1,113 people. The species of house dust mite, Dermatophagoides pteronyssinus and Dermatophagoides farinae was the highest at 8.7% and 8.6%. After adjusted by age, gender, smoking and education level, odds ratio of flower plant farmers is 4.467(95% CI: 2.094-9.527) and fruit farmer is 2.275(95% CI: 1.096-4.721). In addition, the rate of sensitization to grass pollen mixture of the flower plant farmers is significantly higher(15.9%, p<0.001) than other allergens. Conclusions: Even farmers, the rate of sensitization to allergens related to the general environment, such as house dust mite is relatively dominant. However, given the presence of potential cross-reactivity between the allergens or distribution showed that the unique aspects of allergen sensitization in the flower growers, occupational cause is not be completely ruled out.

• Journal of agricultural medicine and community health
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• v.40 no.4
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• pp.221-227
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• 2015

Objective: This study assessed whether both physical disability and perceived dependence relate to depression or whether perceived dependence in personal care activities, household activities, community mobility and recreational activities is an intermediate step in the relationship between physical disability and depressive symptoms. Methods: Data come from a cross-sectional survey of 209 women, aged 55 or older, with osteoarthritis (OA). Mediation analyses occurred in four step and included logistic regression analyses as outlined by Baron & Kenny. Results: The results from step 1 showed that greater difficulty with each domain of physical disabilities was significantly related to greater perceived dependence. In step 2, greater perceived dependence was significantly associated with greater depressive symptoms in all domains. Step 3 analyses showed that greater physical disabilities in each domain were significantly associated with depression. The final step testing mediation indicated that personal care activities, household activities and community mobility were fully mediated by perceived dependence. That was, once dependence was taken into account, the relationship between physical disabilities and depression was no longer significant. Partial mediation was found for dependence and recreational activity limitations. Conclusion: It is important to take into account the experience of perceived dependence as a mediator in understanding the relationship between disability and depression in the domains of personal care, household, and community mobility. To conclude, these findings point to the importance of taking into account an individual's reaction to their disability rather than just focusing on the severity of disability.