• Journal of Korean Society of Water and Wastewater
• /
• 제33권5호
• /
• pp.353-366
• /
• 2019

This research proposes an optimal flushing operation technique in an effort to prevent secondary water pollutions and accidents in aged pipes, and to improve the cleaning effect of unidirectional flushing. Water flow directions were analyzed using EPANET 2.0, while flushing and air scouring experiments in forward and reverse directions were performed in the field. In 42 experiments, average residual chlorine concentration and turbidity were improved after cleaning compared to before cleaning. It was found that even when the same cleaning method was used, further improvement of cleaning effect was possible by applying air injection and reverse direction cleaning techniques. By means of one-way ANOVA(Analysis of variance), it was also possible to statistically verify the need of actively utilizing air injection and reverse direction cleaning. Based on correlation between turbidity and TSS, the total amount of suspended solids removal was estimated for 874 flushing operations and 194 air scouring operations. The result showed that air scouring used more discharge water than flushing by an average of $4.9m^3$ yet with larger amounts of suspended solids removal by an average of 145.9 g. The result of analysis on turbidity values from 887 flushing operations showed low cleaning effect of unidirectional flushing for the pipes with diameters over 300 mm. In addition, the turbidity values measured during cleaning showed an increasing tendency as pipe age increased. The methodology and results of this research are expected to contribute to the efficient maintenance and improvement of water quality in water distribution networks. Follow-up research involving the measurement of water quality at regular time intervals during cleaning would allow a more accurate comparison of discharge water quality characteristics and cleaning effects between different cleaning methods. To this end, it is considered necessary to develop a standardized manual that can be used in the field and to provide relevant trainings.

• Korean Journal of Soil Science and Fertilizer
• /
• 제43권6호
• /
• pp.864-871
• /
• 2010

At the current situation of continuous utilization of heavy metal contaminated upland for agricultural purpose in Korea, minimizing transport of heavy metals from soil to crops is important for securing safety of human health. The present study (in field scale) examined the efficiency of several soil amendments (dolomite, steel slag, lime, zeolite, and compost) on reduction of phytoavailable heavy metals (Cd, Cu, Pb, and Zn) in soil through comparison with no amendment treatment and clean soil cover treatment. For determination of the phytoavailability, 1 M $NH_4NO_3$ extraction and red pepper cultivation were introduced. Among the amendments, in general, dolomite and steel slag were the most effective in reduction of metal (Cd, Pb, and Zn) phytoavailability resulting in less accumulation of these metals in shoot and fruit of red pepper. However, dolomite and steel slag treatment was not as effective as clean soil cover treatment which showed the least metal accumulation in red pepper fruit. Nevertheless, with taking into account the cost, treatment of dolomite or steel slag can be competitive method because the current study showed that dolomite or steel slag treatment reduced accumulated heavy metal concentration effectively in both shoot and fruit of red pepper compared to those from control soil and the concentration in fruit was within the standard value (<0.2 mg $kg^{-1}$ for both Cd and Pb).

• Korean Journal of Food Science and Technology
• /
• 제53권6호
• /
• pp.739-748
• /
• 2021

This study focuses on the use of rice in the production of gluten-free rice udon (GFU) through an optimized mixing ratio, using the Box-Behnken response surface methodology (RSM). Different additional levels of rice flour (A, 40-60 g), acetylated distarch adipate (B, 10-20 g), and trehalose (C, 0-3 g) were used as variables, while water absorption level, volume, cooking loss, solid yield, lightness, texture properties, proximate compositions of GFU and turbidity of cooking water were set as responses in the RSM design model. The optimum mixing ratio for the preparation of gluten-free rice udon was obtained for 60.00 g of rice flour, 18.81 g of acetylated distarch adipate without the addition of trehalose. The response values of the optimized samples were water absorption (60.94%), volume (34.94%), turbidity of the cooking water (0.37), cooking loss (4.77%), solid yield (1.55 g), lightness value (70.04), hardness (2.53 N), springiness (0.18), gumminess (10.45 N), chewiness (1.83 N), and cohesiveness (2.89). This study has shown that rice flour can replace wheat flour to manufacture udon at an optimized mixing ratio successfully derived by statistical estimation method.

• Food Engineering Progress
• /
• 제13권4호
• /
• pp.275-281
• /
• 2009

Sesame oils are partially mixed with other vegetable oils due to high price in a Korean market. To find out authentic sesame oil, a mass spectrometer-based electronic nose (MS-based E-nose) was used. Sesame oil (Se) was blended with soybean oil (So) or corn oil (Co) at the ratio (Se:So, Se:Co) of 97:3, 94:6, 91:9, 88:12 and 85:15, respectively. Intensities of each fragment from sesame oil by MS-based E-nose were completely different from those of soybean oil or corn oil. The obtained results were used for discriminant function analysis (DFA). Volatile organic components (VOC) of soybean oil or corn oil were similar to those of fresh air and DFA plot indicated a significant separation of pure sesame oil and pure other oil. The group of the mixed oil was seperated with that of sesame oil in DFA plot and the added amount of soybean oil to sesame oil was correlated with discriminant function first score (DF1). MS based E-nose system could be used as an efficient method to investigate the purity of sesame oil.

• Asian-Australasian Journal of Animal Sciences
• /
• 제32권2호
• /
• pp.257-264
• /
• 2019

Objective: Dairy cattle nutrient requirement systems acknowledge amino acid (AAs) requirements in aggregate as metabolizable protein (MP) and assume fixed efficiencies of MP used for milk protein. Regulation of mammary protein synthesis may be associated with AA input and milk protein output. The aim of this study was to evaluate the effect of nanoemulsified methionine and cysteine on the in-vitro expression of milk protein (casein) in bovine mammary epithelial cells (MAC-T cells). Methods: Methionine and cysteine were nonionized using Lipoid S 75 by high-speed homogenizer. The nanoemulsified AA particle size and polydispersity index were determined by dynamic light scattering correlation spectroscopy using a high-performance particle sizer instrument. 3-(4,5-Dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide assay was performed to determine the cytotoxicity effect of AAs with and without nanoionization at various concentrations (100 to $500{\mu}g/mL$) in mammary epithelial cells. MAC-T cells were subjected to 100% of free AA and nanoemulsified AA concentration in Dulbecco's modified Eagle medium/nutrient mixture F-12 (DMEM/F12) for the analysis of milk protein (casein) expression by the quantitative reverse transcription polymerase chain reaction method. Results: The AA-treated cells showed that cell viability tended to decrease (80%) in proportion to the concentration before nanogenesis, but cell viability increased as much as 90% after nanogenesis. The analysis of the expression of genetic markers related to milk protein indicated that; ${\alpha}_{s2}$-casein increased 2-fold, ${\kappa}$-casein increased 5-fold, and the amount of unchanged ${\beta}$-casein expression was nearly doubled in the nanoemulsified methionine-treated group when compared with the free-nanoemulsified methionine-supplemented group. On the contrary, the non-emulsified cysteine-administered group showed higher expression of genetic markers related to milk protein ${\alpha}_{s2}$-casein, ${\kappa}$-casein, and ${\beta}$-casein, but all the genetic markers related to milk protein decreased significantly after nanoemulsification. Conclusion: Detailed knowledge of factors, such nanogenesis of methionine, associated with increasing cysteine and decreasing production of genetic markers related to milk protein (casein) will help guide future recommendations to producers for maximizing milk yield with a high level of milk protein casein.

• The Korea Journal of Herbology
• /
• 제29권2호
• /
• pp.15-21
• /
• 2014

Objectives : The purpose of this study was to investigate inhibitory effects of steamed Polygonatum odoratum extract (POE) on differentiation and adipogenesis in 3T3-L1 adipocytes. Methods : Polygonatum odoratum (P. odoratum) extract was extracted with ethyl acetate. Total phenolic and flavonoid contents in POE were measured for antioxidant activity. The spectrophotometric method was used to determine the DPPH and ABTS radical scavenging activity and ferric-reducing antioxidant potential (FRAP). MTT assay was examined for cell toxicity, oil red O staining was performed for intracelluar adipogenesis in differentiated 3T3-L1 adipocytes. Western blot analysis for measurement of CCAAT/enhancer-binding protein ${\alpha}$ ($C/EBP{\alpha}$), peroxisome proliferator-activated receptor${\gamma}$ ($PPAR{\gamma}$) and AMP-activated protein kinase (AMPK) expressions were performed. Results : The results revealed that POE has antioxidant activities. Contents of total polyphenolics and flavonoids were $50.83{\pm}1.52$ GAE mg/100g dry weight of POE and $17.05{\pm}2.47$ RE mg/100g dry weight of POE, respectively. DPPH radical scavenging activity, and FRAP in 10 mg/ml concentration were $92.1{\pm}0.6%$, $244.8{\pm}9.0{\mu}M$ Fe(II) and ABTS inhibition in 5 mg/ml concentration was $84.8{\pm}4.1%$. Treatment of POE in adipocytes inhibited the differentiation and adipogenesis of 3T3-L1 adipocytes compared to those of vehicle control. Additionally, protein expressions of $C/EBP{\alpha}$ and $PPAR{\gamma}$, major transcription factor for the adipogenic genes, were significantly decreased compared to those of vehicle control (p<0.05). Futhermore, phosphorylation of AMPK was increased in 3T3-L1 adipocytes treated with POE compared to that of vehicle control (p<0.05). Conclusions : we demonstrate that steamed P. odoratum extract (POE) has potentiating antioxidant activities, inhibits differentiation and lipid accumulation and also induces energy expenditure in adipocytes, which may contribute to antiobesity property.

• The Korea Journal of Herbology
• /
• 제28권6호
• /
• pp.47-51
• /
• 2013

Objectives : The Illicii Veri Fructus was not only traditional medicine but also food in Asia. The aim of this study was selection of optimum solvent in the fruit of Illicii Veri Fructus because an appropriate solvent affect a medicinal effect. Methods : Illicii Veri Fructus was carried out ultrasonic-assisted extraction as various solvents. Two main compounds, p-anisaldehyde and anethole, were successfully analyzed by high performance liquid chromatography-photodiode array detector (HPLC-PDA) and carried out method validation according to ICH guideline. The optimum solvent selected by comparing with yields of two main ingredients. Results : The p-anisaldehyde and anethole were detected at approximately 8.0 min and 19.8 min, respectively. It was all below 5.0% that RSD of retention time and peak area for two main peaks. Calibration curves of two compounds were good linearity as $R^2$ >0.9999. All of the precisions and accuracy were good intra-day and inter-day as below 5.0% RSD. Limited of detection (LOD) of p-anisaldehyde and anethole were analyzed as $0.134{\mu}g/mL$ and $4.286{\mu}g$, respectively. Limited of quantification (LOQ) of two compounds were $0.407{\mu}g$ and $12.989{\mu}g$, respectively. As a result of this study, p-anisladehyde was detected as 0.209 ~ 0.467%, however anethole was not detected in the distilled water. Conclusions : Anethole was main component as 5.329 ~ 6.815% except for water extraction. Methanol extraction among various solvents was detected the highest contents of p-anisaldehyde and anethole as 0.467(${\pm}0.008$)% and 6.815(${\pm}0.220$)%, respectively.

• Journal of the Korean Society of Fisheries and Ocean Technology
• /
• 제58권1호
• /
• pp.39-48
• /
• 2022

Using environmental DNA (eDNA) in the fisheries and oceanography fields, research on the diversity of biological species, the presence or absence of specific species and quantitative evaluation of species has considerably been performed. Up to date, no study on eDNA has been tried in the area of fisheries acoustics in Korea. In this study, the biomass of a dominant species in the northwestern waters of Jeju Island was examined using 1) the catch ratio of the species from trawl survey results and 2) the ranking ratio of the species from the eDNA results. The dominant species was Zoarces gillii, and its trawl catch ratio was 68.2% and its eDNA ratio was 81.3%. The Zoarces gillii biomass from the two methods was 7199.4 tons (trawl) and 8584.6 tons (eDNA), respectively. The mean and standard deviation of the acoustic backscattering strength values (120 kHz) from the entire survey area were 135.5 and 157.7 m²/nm², respectively. The strongest echo signal occurred at latitude 34° and longitude 126°15' (northwest of Jeju Island). High echo signals were observed in a specific oceanographic feature (salinity range of 32-33 psu and the water temperature range of 19-20℃). This study was a pilot study on evaluating quantitatively aquatic resources by applying the eDNA technique into acoustic-trawl survey method. Points to be considered for high-quality quantitative estimation using the eDNA to fisheries acosutics were discussed.

• Korean Journal of Culture and Social Issue
• /
• 제17권4호
• /
• pp.415-434
• /
• 2011

Leisure is an important role on happiness and health in midlife. Nevertheless, there has been little research using a longitudinal method in Korea to identify the influence of leisure on happiness and health. Current study examined the effect of leisure satisfaction and time for leisure activities on happiness(SHS) and health-related variables(psychological symptoms, physical symptoms, and quality of sleep) in middle aged adults(40-65 years) by longitudinal data. Two surveys were conducted with 10 months' interval and total 145 respondents(M=49.45) participated in both surveys. Hierarchical regression analysis was employed to investigate that both leisure satisfaction and time for leisure activities in the first time have an effect on happiness and health-related variables in the second time after controlling for each happiness and health variables in the first time as well as demographic variables. We found that leisure satisfaction influenced beneficially on happiness(SHS), psychological symptoms, and quality of sleep after 10-month. Similarly, time for leisure activities had effect on happiness(SHS), psychological symptoms, and physical symptoms after 10-month. The implication for study were discussed.

• Journal of Radiopharmaceuticals and Molecular Probes
• /
• 제7권2호
• /
• pp.119-125
• /
• 2021

⁸²Sr for ⁸²Rb generator was produced through the irradiation of the proton beam on the ^nat.RbCI target at the target irradiation facility installed at the end of the Rl-dedicated beamline of the 100 MeV proton linear accelerator of KOMAC (Korea Multi-purpose Accelerator Complex). The average current of the proton beam was 1.2 µA for irradiation time of 150 min. For the separation and purification of the ⁸²Sr from ^nat.RbCI irradiated, Chelex-100 resin was used. The activities of ⁸²Sr in the irradiated ^nat.RbCI target solution and after purification were 45.29 µCi and 43.4 µCi, respectively. The separation and purification yield was 95.8%. As an adsorbent to be filled in the generator for ⁸²Sr adsorption hydrous tin oxide was selected. The adsorption yield of ⁸²Sr into the generator adsorbent was > 99 %, and the total amount of ⁸²Sr adsorbed to the generator was 21.6 µCi as of the day of the ⁸²Rb elution experiment. When the elution amount was 22 mL, the maximum⁸²Rb elution yield was 93.3%, and the elution yield increased as the flow rate increased. After the eluted ⁸²Rb was filled in the correction phantom of the small PET for animals, a PET image was taken. The image scan time was set to 5 min, and the phantom PET image was successfully obtained. As results of impurity analysis on eluted ⁸²Rb using ICP-MS, ^nat.Rb stable isotopes that compete in vivo of ⁸²Rb were identified as undetected levels and were determined to be No-Carrier-Added (NCA).