• Asian-Australasian Journal of Animal Sciences
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• v.24 no.9
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• pp.1314-1317
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• 2011

To evaluate the effects of pulsed electric field (PEF) application on scalder and chiller water on Campylobacter contamination, four different treatments under three different water conditions including hard scalder water ($55^{\circ}C$), soft scalder water ($45^{\circ}C$) and chiller water, were applied as follows: i) a control treatment with no salt and no electric treatment, ii) a PEF only treatment, iii) a PEF treatment with 0.5% salt water, and iv) a PEF treatment with 1% salt water treatment. The use of PEF in hard scalding water showed an effect of reducing Campylobacter when compared to the control during the 200 s timeframe. With the addition of salt, the intervention caused at least 5.81 log CFU/ml reduction of Campylobacter counts after 200 s of PEF exposure. Similar effects were observed under soft scalding conditions. Campylobacter reductions were evident under chilling conditions with up to 2.00 log for PEF only, 5.77 log for PEF+0.5% salt and 2.69 log for PEF+1% salt treatment in water. Therefore, the current PEF setting for the scalder and chiller water can be successfully used to reduce pathogenic loads of Campylobacter on broiler chicken carcasses, and further research may be necessary to apply it in the poultry processing industry.

• Journal of the Korean Geophysical Society
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• v.6 no.2
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• pp.57-69
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• 2003

In this paper the theoretical method to analyse the pore water pressures in the bed under the oscillating water pressure is developed. In the former researches the validity of the theoretical treatment for the one-dimensional problem has been verified. However, the one-dimensional treatment is not sufficient to obtain the precise information concerning the many practical problems. From this point of view, in this study, we derive the fundamental equations for the general three-dimensional sand layer under the oscillating water pressure. The validity of this theoretical method is verified by experiments for the two-dimensional problems.

• The Korean Journal of Physiology and Pharmacology
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• v.25 no.6
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• pp.517-523
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• 2021

The present study aims to investigate the impact of hydrogen-rich water on the lactic acid level in metformin-treated diabetic rats under hypoxia. Thirty Sprague-Dawley rats were randomly divided into five groups, including normal diet group, and diabetes model (DM) group, DM + metformin treatment (DMM) group, DMM + hypoxia treatment (DMMH) group and DMMH + hydrogen-rich water (DMMHR) group. We found that the levels of lactic acid, pyruvate and lactate dehydrogenase were significantly lower in the blood of DMMHR group than DMMH group. Superoxide dismutase and glutathione levels in liver and heart were significantly higher in DMMH group after hydrogen-rich water treatment, while malondialdehyde and oxidized glutathione levels were decreased in DMMHR group when compared with DMMH group, which indicates that hydrogen-rich water could reduce oxidative stress. qPCR analysis demonstrated that that pro-apoptotic genes Bax/Caspase-3 were upregulated in DM group and metformin treatment suppressed their upregulation (DMM group). However, hypoxic condition reversed the effect of metformin on apoptotic gene expression, and hydrogen-rich water showed little effect on these genes under hypoxia. HE staining showed that hydrogen-rich water prevented myocardial fiber damages under hypoxia. In summary, we conclude that hydrogen-rich water could prevent lactate accumulation and reduce oxidant stress in diabetic rat model to prevent hypoxia-induced damages. It could be served as a potential agent for diabetes patients with metformin treatment to prevent lactic acidosis and reduce myocardial damages under hypoxic conditions.

• Journal of environmental and Sanitary engineering
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• v.6 no.1
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• pp.103-108
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• 1991

Visibility studies are conducted in oxidizing organic compounds with ozone to investigate the oxidation in the waste and sewage water. While the ozone has been used as one of the major oxidation of the waste and sewage water, it is not effective to distroy the polluted organic compounds with the practical concentration in waste water treatment. The result are shown follows ; 1. Upon oxidizing organic compound with ozone, the former is much oxidized under three meters and the latter under the ABS waste water. 2. In case of being oxidized organics waste water with ozone codis, much removed under medicine and chemical waste water than anothers of primary treatment process. 3. The final treated waste water of oxidizing organics is higher than that of filtered water or sedimented water. Specially in organics waste water the colority after oxidizing decrease from 95% to 99.9% this suggests that any organic compounds produced during ozonation night be dissdved in the final treated waste water.

• Journal of Advanced Marine Engineering and Technology
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• v.34 no.3
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• pp.391-398
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• 2010

This study is currently giving priority to developing the ballast water treatment system using ozone(Ozone BWTS). The Ozone BWTS, were equipped on the real merchant vessel named as M. V. Hyundai Hong Kong to carried out shipboard tests of ballast water treatment system in accordance with orders of IMO G8 Guidelines. The study results show that the Ozone BWTS is capable of meeting the Ballast Water Performance Standard under Regulation D-.2 of the International Convention for the Control and Management of Ships’ Ballast Water and Sediments, and also the more stringent standards being proposed under US legislation.

• KOREAN JOURNAL OF CROP SCIENCE
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• v.48 no.6
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• pp.506-515
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• 2003

Six barley varieties that showed different degree of drought tolerance were grown with and without drought stress treatment (control), and investigated for the temporal changes in growth and several physiological traits after drought treatment. Soil water potential was -0.05 ㎫ at the initial stage of drought treatment and dropped to -0.29 ㎫ at 19 days after withholding irrigation. Soil water potential (SWP) maintained at -0.05 ㎫ in the control. The dry weight (DW) under the drought treatment were reduced compared to the control as follows: Dicktoo-S (short awn), 69% ; Dicktoo-L (long awn), 70%; Dicktoo-T (tetra), 86%; Dongbori-1, 69%; Suwonssalbori-365, 55% and Tapgolbori, ,37%. Dicktoo lines and Dongbori-1 were more tolerant than Suwonssalbori-365 and Tapgolbori. Leaf relative water contents (RWC) and leaf water potential (LWP) decreased obviously under the drought condition, the decrease being greater especially in the less drought-tolerant barley genotypes. Dongbori-1 and Dicktoo-L in drought treatment showed net photosynthesis of 38% and 17% compared to the control, respectively, and the other four genotypes much lower photosynthesis of 1.1% to 7.0%. Stomatal conductance, mesophyll conductance, and the photochemical efficiency (Fv/Fm) of PS II were reduced by drought treatment, the reduction being greater in drought-sensitive genotypes. The drought-tolerant genotypes had greater osmotic adjustment (OA) capacity under water stress. Thus, the decrease of RWC and LWP was lower and the turgor pressure conservation capacity was higher under water stress in drought-tolerant genotypes. Drought-tolerant genotypes showed less decrease of photosynthesis because stomatal conductance, mesophyll conductance and the ratio (Fv/Fm) of the variable to maximal fluorescence of drought-resistant genotype was decreased less in the drought stress condition. In conclusion, the drought-tolerant genotypes had better water conservation capacity through efficient OA, and this led to the lower decrease of photosynthesis and growth in water stress condition.

• Journal of Animal Science and Technology
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• v.64 no.4
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• pp.782-791
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• 2022

The purpose of this study is to evaluate the effects of multiple cooling systems and different drinking water temperatures (DWT) on the performance of sows and their hair cortisol levels during heat stress. In this study, the effect of four different cooling systems: air conditioner (AC), cooling pad (CP), snout cooling (SC), and mist spray (MS), and two DWT, namely low water temperature (LWT) and high water temperature (HWT) on 48 multiparous sows (Landrace × Yorkshire; 242.84 ± 2.89 kg) was tested. The experiment is based on the use of eight replicas during a 21-days test. Different behaviors were recorded under different cooling treatments in sows. As a result, behaviors such as drinking, standing, and position change were found to be lower in sows under the AC and CP treatments than in those under the SC and MS treatments. Lying behavior increased under the AC and CP systems as compared with that under the SC and MS, systems. The average daily feed intake (ADFI) in sows and weight at weaning in piglets was higher under the AC, CP, and LWT treatments than under the SC, MS and HWT treatments. Sows subjected to SC and MS treatment showed higher hair cortisol levels, rectal temperature, and respiratory rate during lactation than those under AC and CP treatments. Hair cortisol levels, rectal temperature, and respiratory rate were also higher under the HWT than under the LWT treatment. As per the results of this study, the LWT has no significant effect on any of the behavioral factors. Taken together, the use of AC and CP cooling treatment is highly recommended to improve the behavior and to reduce the stress levels in lactating sows.

• Journal of Environmental Science International
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• v.21 no.7
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• pp.837-843
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• 2012

The aims of this study were to investigated the occurrence of caffeine and carbamazepine in Nakdong river basin (8 mainstreams and 2 tributaries) and the behavior of caffeine and carbamazepine under drinking water treatment processes (conventional and advanced processes). The examination results showed that caffeine was detected at all sampling sites (5.4~558.5 ng/L), but carbamazepine was detected at five sampling sites (5.1~79.4 ng/L). The highest concentration level of caffeine and carbamazepine in the mainstream and tributaries in Nakdong river were Goryeong and Jinchun-cheon, respectively. These pharmaceutical products were completely removed when they were subject to conventional plus advanced processes of drinking water treatment processes. Conventional processes of coagulation, sedimentation and sand-filtration were not effective for their removal, while advanced processes of ozonation and biological activated carbon (BAC) filtration were effective. Among these pharmaceuticals, carbamazeoine was more subject to ozonation than caffeine.

• Journal of Bio-Environment Control
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• v.26 no.2
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• pp.146-150
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• 2017

This research investigated the effect of photo/dark period and relative humidity during dark period on the growth and quality of water dropwort in a closed-type plant factory system. At 30 days after planting, the shoot fresh weight of water dropwort under relative humidity of 60/90%(light/dark) treatment significantly higher than that under relative humidity of 60/60% treatment. The shoot fresh weight of water dropwort increased by extending light period under relative humidity of 60/60% treatment, but 16/8h photo/dark period showed the best shoot fresh weight, followed by 20/4h and 22/2h under relative humidity of 60/90% treatment. In the relative humidity of 60/90% treatment, the tipburn occurrence was reduced under 16/8h photo/dark period condition as 1.4%, whereas it was significantly increased under 20/4h and 22/2h of relatively long light time duration as 15.5% and 30.3%, respectively. In the relative humidity of 60/60% treatment, the tipburn occurrence was 15.5% under 16/8h photo/dark period condition and those under 20/4h and 22/2h photo/dark period condition were higher than 25%. The stem hardness of water dropwort was lowest in relative humidity of 60/90% and 16/8h photo/dark period treatment. The mineral contents of leaves were decreased by extending light period, but the contents of Ca were not different significantly among the treatments except the 60/60% and 22/2h treatment.

• Journal of Korean Society of Water and Wastewater
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• v.20 no.1
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• pp.138-146
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• 2006

The characteristics of backwash and concentrate discharges depend upon the quality of the water being treated and the net recovery of the membrane system. This paper is to indicate a design methods on the capacities of residuals treatment facilities in membrane processes for drinking water. We operated a demonstration membrane plant with a recovery rate of 90% for designing G-water treatment plant. We investigated on design parameter (optimum coagulant dosage and surface loading rate etc.) to design efficiently the residuals treatment facilities. The settling test was conducted with 1m columns dosing PACl to kaolin and membrane residuals under the experimental condition that discharge permit was under a 60mg/L. When the quantity of membrane residuals was $1,575m^3/day$, the estimated results for 1st thickener demonstrated the surface loading rate of 14.4m/day, detention time of 5.83hr, available depth of 3.5m.