• Journal of Embryo Transfer
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• v.25 no.3
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• pp.145-148
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• 2010

Oxygen consumption has been regarded as a useful indicator for assessment of mammalian embryo quality. This study was performed to investigate whether oxygen consumption reflects morphological grade of in vivo derived bovine blastocyst-stage embryos (blastocyst). The oxygen consumption of in vitro produced blastocyst was compared to its total cell number. In addition, pregnant rate was measured after transplantation of in vivo blastocysts with different oxygen consumption. The quality of blastocyst collected on day 7 after artificial insemination was categorized as grade I and II (G I and G II) based on microscopic observation of the morphology. Oxygen consumption of blastocyst was measured using a scanning electrochemical microscopy (SECM) and total cell number of in vitro blastocyst was enumerated by counting cells stained by propidium iodide. Pregnancy of recipient cow was confirmed with rectal palpation after 60 days of embryo transfer. The oxygen consumptions of G I blastocysts were significantly higher than those of G II blastocysts ($10.2{\times}10^{15}/mol\;s^{-1}$ versus $6.4{\times}10^{15}/mol\;s^{-1}$, p<0.05). Total cell numbers of in vitro blastocysts were 74.8, 90.7, and 110.2 in the oxygen consumption of below 10.0, 10.0~12.0, and over $12.0{\sim}10^{15}/mol\;s^{-1}$ respectively. Total cell number was significantly increased in embryos with high oxygen consumption (p<0.05). Pregnant rate in recipient cow was 0, 50, and 85.7% in the transplantation of embryo with the oxygen consumption of below 10.0, 10.0~12.0, and over $12.0{\times}10^{15}/mol\;s^{-1}$, respectively. These results suggest that measurement of oxygen consumption may help increase the pregnant rate of bovine embryos.

• The Sea:JOURNAL OF THE KOREAN SOCIETY OF OCEANOGRAPHY
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• v.26 no.2
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• pp.82-95
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• 2021

We investigated the temporal and spatial distribution characteristics of chemical oxygen demand (COD) and total organic carbon (TOC) in all 13 locations of Masan Bay from February to November in 2015. The COD and TOC contents were high during the June-August period when the pollution load increased. In particular, the concentrations of COD and TOC were about twice as high in the surface water as in the bottom water. In spatial distribution, the COD and TOC concentrations at the inner bay were about twice as high as those of the outer bay in Masan Bay. As a result of estimating the oxidation efficiency of COD from the surface layer of Masan Bay in 2015 based on the theoretical oxygen demand (TOD), it was at the level of about 23%. Due to the low oxidation efficiency of COD, there is a risk that the organic matter in Masan Bay will be somewhat underestimated. Therefore, for quantitative analysis of organic matter, COD and TOC analyses need to be combined.

• Journal of Food Hygiene and Safety
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• v.32 no.5
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• pp.396-403
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• 2017

The purpose of this study was to investigate water quality for irrigation water used in Napa cabbage cultivation. The water samples were analyzed for physiochemical and microbiological quality for a total of 111 samples including surface water (n = 75) and groundwater (n = 36) collected from five different regions where Napa cabbage is massively grown. As a conclusion, the levels of fecal indicators for surface water were higher than those for groundwater. The numbers of coliform from surface water and groundwater were 1.96-4.96 and 0-3.98 log MPN/100 mL, respectively. Enterococci were detected in 95% (72/75) of surface water samples and 22% (8/36) of groundwater samples. Besides, 97% (73/75) of surface water samples were observed being contaminated with Escherichia coli, and 22% (8/36) of groundwater sample was positive for E. coli. In the case of surface water, E. coli and coliform correlate to T-P, and enterococci showed relevance to the suspended solid (SS) and biochemical oxygen demand (BOD). In groundwater, fecal indicator bacteria showed relevance to the SS and chemical oxygen demand (COD). These results could be provided as fundamental date for establishing microbial standard of water used in leafy vegetables cultivation.

• Korean Journal of Fisheries and Aquatic Sciences
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• v.8 no.3
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• pp.150-156
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• 1975

This paper dealt itself with the relation of the heat release rate with crank angle in combustion process by adjusting the injection time, injection amount and engine speed of diesel engine. The result of test were obtained by analyzing indicator diagram of KUBOTA 2LKE diesel engine, where the indicator was used Tertronix oscilloscope. The combustion period of diesel engine is composed of premixed burning time and combustion controlled time. The larger the premixed burning region, the higher efficiency was obtained with the higher maximum pressure than at the time of the normal smooth operation. The longer the combustion controlled time, the lower the maximum pressure than the period of the normal operation, but the efficiency was decreased. The region of premixed burning was principally controlled by injection delay, but combustion controlled time was affected when oxygen and fuel were mixed. Efficiency of engine was increased at the time of earlier injection time under the constant injection amount, and engine speed, but the pressure increasing was observed higher than the efficiency increasing.

• Journal of the Mineralogical Society of Korea
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• v.23 no.4
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• pp.403-411
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• 2010

Essentials of understanding the geochemical evolution and geophysical processes in Earth's system are macroscopic properties and atomistic (and electronic) structures of Earth materials. Recent advances in quantum calculations based on the density functional theory allow us to unveil the previously unknown details of local atomic structures in diverse silicates in Earth's interior. Here, we report the O K-edge ELNES (energy-loss near-edge structure; ELNES) spectra and PLDOS (partial local density of states) for oxygen atoms in ${\alpha}$-quartz and stishovite using the quantum calculations based on FP-LAPW (full potential linearized augmented plane wave). The calculated O K-edge ELNES spectrum of ${\alpha}$-quartz shows a strong peak at ~538 eV due to comer-sharing oxygen linking two $SiO_4$ tetrahedra and that for stishovite shows two distinct peaks at ~537 and ~543 eV corresponding to edge-sharing oxygen linking $SiO_6$ octahedra. The significant differences in spectral features of O K-edge ELNES spectra suggest that the O K-edge features can be useful indicator to distinguish various oxygen sites in diverse crystal and amorphous silicates in the Earth's interior.

• Journal of Environmental Health Sciences
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• v.38 no.3
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• pp.251-260
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• 2012

Objectives: The purpose of this study was evaluating the applicability of the circulation dielectric barrier plasma process (DBD) for efficiently treating non-biodegradable wastewater, such as phenol. Methods: The DBD plasma reactor system in this study consisted of a plasma reactor (discharge, ground electrode and quartz dielectric tube, external tube), high voltage source, air supply and reservoir. Effects of the operating parameters on the degradation of phenol and $UV_{254}$ absorbance such as first voltage (60-180 V), oxygen supply rate (0.5-3 l/min), liquid circulation rate (1.5-7 l/min), pH (3.02-11.06) and initial phenol concentration (12.5-100 mg/l) were investigated. Results: Experimental results showed that optimum first voltage, oxygen supply rate, and liquid circulation rate on phenol degradation were 160 V, 1 l/min, and 4.5 l/min, respectively. The removal efficiency of phenol increased with the increase in the initial pH of the phenol solution. To obtain a removal efficiency of phenol and COD of phenol of over 97% (initial phenol concentration, 50.0 mg/l), 15 min and 180 minutes was needed, respectively. Conclusions: It was considered that the absorbance of $UV_{254}$ for phenol degradation can be used as an indirect indicator of change in non-biodegradable organic compounds. Mineralization of the phenol solution may take a relatively longer time than that required for phenol degradation.

• Korean Journal of Soil Science and Fertilizer
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• v.46 no.5
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• pp.327-332
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• 2013

This survey was conducted to obtain basic data about organic matter such as BOD (Biochemical Oxygen Demand), COD (Chemical Oxygen Demand), DOC (Dissolved Organic Carbon) and TOC (Total Organic Carbon) in agricultural water in Gyeongnam province. BOD and COD are currently used for water quality indices, but adoption of TOC is being suggested. The surface water samples were collected at 39 locations in Gyeongnam province in April, July and October. Average concentrations of BOD, COD, DOC and TOC were 1.6, 3.3, 5.3 and $5.7mg\;L^{-1}$, respectively. In July, average concentrations of BOD and COD were 2.4 and $3.9mg\;L^{-1}$, respectively, showing these values were higher than other months. Average concentrations of TOC in April, July and October were 4.8, 7.4 and $4.8mg\;L^{-1}$, respectively. This suggested that the highest value of TOC was in July. Average decomposition efficiencies for BOD-C/TOC and COD-C/TOC were 11.4 and 23.9%, respectively. Correlation coefficient of TOC and DOC was higher by 0.995, whereas that of TOC and COD was lower by 0.763. Especially, TOC and DOC were highly related than others.

• Journal of Environmental Health Sciences
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• v.42 no.4
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• pp.280-292
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• 2016

Objectives: The objective of this study was to build COD regression models for the Han River and evaluate water quality. Methods: Water quality data sets for the dry season (as of January) during a four-year period (2012-2015) were collected from the database of the Han River automatic water quality monitoring stations. Statistical techniques, including combined genetic algorithm-multiple linear regression (GA-MLR) were used to build five-descriptor COD models. Multivariate statistical techniques such as principal component analysis (PCA) and cluster analysis (CA) are useful tools for extracting meaningful information. Results: The $r^2$ of the best COD models provided significant high values (> 0.8) between 2012 and 2015. Total organic carbon (TOC) was a surrogate indicator for COD (as COD/TOC) with high reliability ($r^2=0.63$ in 2012, $r^2=0.75$ for 2013, $r^2=0.79$ for 2014 and $r^2=0.85$ for 2015). The ratios of COD/TOC were calculated as 2.08 in 2012, 1.79 in 2013, 1.52 and 1.45 in 2015, indicating that biodegradability in the water body of the Han River was being sustained, thereby further improving water quality. The BOD/COD ratio supported these findings. The cluster analysis revealed higher annual levels of microorganisms and phosphorous at stations along the Hangang-Seoul and Hantangang areas. Nevertheless, the overall water quality over the last four years showed an observable trend toward continuous improvement. These findings also suggest that non-point pollution control strategies should consider the influence of upstreams and downstreams to protect water quality in the Han River. Conclusion: This data analysis procedure provided an efficient and comprehensive tool to interpret complex water quality data matrices. Results from a trend analysis provided much important information about sources and parameters for Han River water quality management.

• The Korean Journal of Physiology and Pharmacology
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• v.9 no.5
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• pp.283-289
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• 2005

Endothelium, particularly pulmonary endothelium, is predisposed to injury by reactive oxygen species (ROS) and their derivatives. Heme oxygenase (HO) has been demonstrated to provide cytoprotective effects in models of oxidant-induced cellular and tissue injuries. In the present study, we investigated the effects of YS 49 against oxidant [tert-butylhydroperoxide (TBH)]-induced injury using cultured sheep pulmonary artery endothelial cells (SPAECs). The viability of SPAECs was determined by quantifying reduction of a fluorogenic indicator Alamar blue. We found that TBH decreased cell viability in a timeand concentration-dependent manner. YS 49 concentration- and time-dependently increased HO-1 induction on SPAECs. As expected, YS 49 significantly decreased the TBH-induced cellular injury. In the presence of zinc protophorphyrin, HO-1 inhibitor, effect of YS 49 was significantly inhibited, indicating that HO-1 plays a protective role for YS 49. Furthermore, YS 49 showed free radical scavenging activity as evidenced by 1,1-diphenyl-2-picrylhydrazyl (DPPH) and inhibition of lipid peroxidation. However, YS 49 did not inhibit apoptosis induced by lipopolysaccharide (LPS) in SPAECs. Taken together, HO-1 induction along with strong antioxidant action of YS 49 may be responsible for inhibition of TBH-induced injury in SPAECs.

• The Journal of Korean Medicine
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• v.35 no.2
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• pp.12-18
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• 2014

Objectives: This was a retrospective case series about the clinical effect of integrated approach with behavior therapy for obstructive sleep apnea (OSA). Methods: Medical records of twelve patients with OSA who were treated with behavior modification including nasal breathing with oral appliances and sleep in lateral position, oral administration of herbal medicines and acupuncture treatment between January and September of 2013 were reviewed. Apnea-hypopnea index (AHI), day time sleepiness, apneas and hypopneas counts during sleep, risk indicator (RI), oxygen desaturation index, average saturation during sleep, lowest desaturation, lowest saturation, snoring events ratio and number of desaturations (%) were assessed before and after treatments with the ApneaLink device, which is a portable diagnostic apparatus for monitoring airflows of the patient's breath at home. Results: After an average 62.67 (SD 37.16) days of treatment, AHI (from 17.67, 12.79 to 8.75, 8.25, p=0.007), RI (from 22.00, 13.26 to 12.09, 8.03, p=0.004), oxygen desaturation index (from 17.33, 12.17 to 8.17, 7.86, p=0.005), and number of desaturations (from 7.00 times, 9.79 to 0.92 times, 1.39, p=0.044) showed significant improvement. Daytime sleepiness improved from 6.5 (3.2) to 3.8 (1.8) but there was no significant difference after treatment (p=0.17). No adverse events related to treatment were observed during participation in the treatment. Conclusion: From this case series, we found that behavior modification with herbal medication and acupuncture may be effective for improving sleep apnea without serious adverse events. Future randomized controlled trials with larger sample size will be necessary for concrete evidence on the benefit of this integrated treatment for OSA.