• Journal of the korean society of oceanography
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• v.31 no.2
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• pp.64-74
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• 1996

Numerical experiments of OAT (Ocean Acoustic Tomography) are carried out in the East Sea of Korea where the canonical ocean has been perturbed by a mesoscale warm eddy and a thermal front. In order to estimate the horizontal and vertical structure of water temperature of the perturbed ocean, the experimental area is divided into 16 cells with 8 pairs of sources and receivers for a horizontal slice and the water column is divided into 8 layers for a vertical slice. The inversely estimated temperature field by using SVD (Singular Value Decomposition) method reveals the eddy and frontal structure clearly. The rms errors of the two horizontal slices are less than $0.4^{\circ}C$ and $1.7^{\circ}C$ at 400 m and 200 m depths, respectively, while the error in the vertical slice is less than $1.0^{\circ}C.$ For better estimation of temperature by OAT method, particularly for the East Sea, a range-dependent ray model should be used to solve the forward problem. At the same time, improvement in computing the refracted ray path between vertical layers is required to obtain more accurate travel time information. The results of the present experiment give rise to a possibility of application of OAT in remote sensing of the ocean thermal structure.

• Journal of The Korean Society of Grassland and Forage Science
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• v.40 no.4
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• pp.279-284
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• 2020

This study aimed to analyze ruminal fermentation, methane emissions, and methanogen levels for different forage feed type and concentrate feed ratios. Alfalfa hay, oat hay, and a feed concentrate were used for in vitro fermentation experiments, at ratios of 9:1, 5:5, and 1:9 (forage:concentrate). After 24 h of incubation, rumen fermentation and methanogen level changes were evaluated. In the low forage treatments, the total gas, CH4, NH3-N, true dry matter digestibility, and total volatile fatty acid were higher than the other treatments, which were used as the parameters on which to assess rumen fermentation (P < 0.05). The feed ratio influenced the copy number for the total archaea and the genus Methanobrevibacter (P = 0.015, P = 0.010). The copy number result trend was like that for CH4 per digested dry matter (DDM). The PCR results and methanogen copy number analysis indicated that the composition of the methanogens affected the CH4 levels, not their copy number. The results of this study can be applied to predict rumen fermentation and methane emission patterns for cattle fed a variety of feedstuffs.

• The Journal of the Acoustical Society of Korea
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• v.23 no.1
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• pp.24-29
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• 2004

In ocean acoustic tomography (OAT), the pulse compression techniques using M-sequences are employed in the many studies for investigating the ocean structures. M-sequences can provide the good time and Doppler resolution in the process of demodulation using matched-filter. The signal-to-noise (SNR) performance at the output of receiver may be improved by manipulating received signal, i. e. coherently averaging. The processing time can be significantly reduced by using fast hadarmard transform (FHT) or fast Fourier transform (FFT). In this paper, we estimate the multipath arrival structures and delay times using the East Korean Sea experiment data and explore the compensation method for the detrimental effects on performance due to sampling rate error. We also analyze the characteristics of the ocean acoustic channels through scattering function, delay power profile, and time dispersions.

• Microbiology and Biotechnology Letters
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• v.36 no.4
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• pp.307-313
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• 2008

The yeast surface expression system, pCTXYN (6.8 kb), of Bacillus endoxylanase gene (xynB, 642 bp) was constructed and introduced into Saccharomyces cerevisiae EBY100 cell. The transformed yeast cell showing the highest endoxylanase activity was selected through the active staining of colonies grown on YPDG medium containing xylan. With the yeast transformant, EBY100/pCTXYN, grown on galactose containing medium, it was found that the endoxylanase was successfully displayed on the yeast cell surface and the xylooligosaccharides were efficiently produced from xylan. The most of endoxylanase activity was detected in the cell fraction and reached about 1.9 unit/mL after 48 h cultivation. The optimized conditions for xylooligosaccharides production from xylan were determined as follows: substrate and its concentration, oat spelt xylan 6%; concentration of yeast whole-cell, 5 unit/mL; temperature, $50^{\circ}C$, and reaction time $2{\sim}4\;h$. When the oat spelts xylan and corncob xylan were hydrolyzed by treatment with cell surface-displayed endoxylanase, xylotriose was formed as a main product.

• Food Science and Biotechnology
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• v.15 no.6
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• pp.942-947
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• 2006

The effect of oat bran extracts on the formation of aberrant crypt foci (ACF) in the colon induced by 1,2-dimethylhydrazine (DMH) was studied in F344 male rats. Extracts were prepared using various combinations of temperature (40, 45, 50, 55, or 60$^{\circ}C:\;X_1$), ethanol concentration (0,5, 10, 15, or 20%: $X_2$), and pH (5, 6, 7, 8, or 9: $X_3$). Among the various extracts tested, one ethanol extract (EE; $45^{\circ}C$, 15% ethanol at pH 6) and one water extract (WE; $50^{\circ}C$ at pH 5) were selected based on their in vitro antitumor activity. The animals were fed with basal diet alone or basal diet supplemented with 0.25 or 0.5% of EE or WE for 6 weeks. During the initial 2 weeks of the 6-week test period, the rats were subcutaneously injected with DMH (30 mg/kg) 4 times for the induction of ACF. DMH induced an average of 322.7 and 142.9 aberrant crypts (AC) and ACF, respectively. A low dose (0.25%) of EE (containing 38.3% ${\beta}$-glucan) and WE (containing 22.8% ${\beta}$-glucan) greatly reduced the numbers of DMH-induced AC and ACF. Significantly, ACF consisting of more than 3 AC were reduced by half in which the effect of EE, containing a higher concentration of ${\beta}$-glucan, was superior to that of WE. These results demonstrate that oat bran extracts may confer protection against colon carcinogenesis.

• Clinical and Experimental Reproductive Medicine
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• v.45 no.1
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• pp.17-24
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• 2018

Objective: To investigate sperm chromatin/DNA integrity, global DNA methylation, and DNMT mRNA transcription in men with oligoasthenoteratozoospermia (OAT) compared with normozoospermic men. Methods: Semen samples from 32 OAT patients who comprised the case group and 32 normozoospermic men who comprised the control group were isolated and purified using a standard gradient isolation procedure according to World Health Organization criteria. DNMT1, DNMT3A, and DNMT3B transcripts were then compared between groups using real-time quantitative reverse-transcription polymerase chain reaction. Global DNA methylation in sperm was determined by an enzyme-linked immunosorbent assay. Protamine deficiency and the proportion of apoptotic spermatozoa were evaluated using chromomycin A3 (CMA3), aniline blue (AB), and toluidine blue (TB) staining, as well as the terminal deoxynucleotidyl transferase dUTP nick end labeling (TUNEL) assay. The p-values < 0.05 were considered to indicate statistical significance. Results: Significantly higher proportions of AB+, TB+, CMA3+, and TUNEL+ spermatozoa, as well as DNMT3A and DNMT3B transcription, were found in the OAT group. Positive correlations were detected between sperm parameters, DNA/chromatin damage, and DNMT3A and DNMT3B transcripts. Global DNA methylation was significantly higher in the OAT patients and had a significant correlation with abnormal results of all sperm chromatin integrity tests, but was not associated with DNMT1, DNMT3A, or DNMT3B expression. Conclusion: Oligoasthenoteratozoospermic men showed abnormal sperm parameters, abnormal chromatin/DNA integrity, and a higher global DNA methylation rate, as well as overexpression of DNMT mRNA.

• Clinical and Experimental Reproductive Medicine
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• v.46 no.3
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• pp.112-118
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• 2019

Objective: Oxidative stress contributes to male infertility, and antioxidants have been recommended for treating idiopathic oligoasthenoteratozoospermia (OAT). There is, however, a lack of agreement on the type, dosing, and use of individual antioxidants or combinations thereof. The purpose of this study was to compare the effects of two doses of coenzyme Q10 (CoQ10) on semen parameters and antioxidant status in men with idiopathic OAT. Methods: In this prospective study, patients with idiopathic OAT received 200 mg/day (n = 35) or 400 mg/day (n = 30) of CoQ10 orally for 3 months. All patients underwent semen analysis according to the fifth editions of the World Health Organization criteria. Total antioxidant capacity (TAC), catalase (CAT) activity, and superoxide dismutase (SOD) activity were measured both before and after treatment. Results: Treatment with CoQ10 (200 mg/day or 400 mg/day) resulted in a significant increase in sperm concentration from baseline ($8.22{\pm}6.88$ to $12.53{\pm}8.11million/mL$, p= 0.019; $7.58{\pm}5.41$ to $12.33{\pm}6.1million/mL$, p= 0.002, respectively), progressive motility ($16.54%{\pm}9.26%$ to $22.58%{\pm}10.15%$, p=0.011; $14.22%{\pm}12.85%$ to $26.1%{\pm}14.52%$, p= 0.001, respectively), and total motility ($25.68%{\pm}6.41%$ to $29.96%{\pm}8.09%$, p= 0.016; $23.46%{\pm}12.59%$ to $34.82%{\pm}14.17%$, p= 0.001, respectively). CoQ10 therapy also increased TAC (p= 0.009, p= 0.001, respectively), SOD activity (p= 0.004, p= 0.001, respectively), and CAT activity (p= 0.039, p= 0.024, respectively). Furthermore, antioxidant measures correlated significantly with seminal fluid parameters (r = 0.36-0.76). Conclusion: CoQ10 supplementation improved semen parameters and antioxidant status in men with idiopathic OAT, with a greater improvement shown in men who took 400 mg/day than in those who took 200 mg/day.

• Korean Journal of Agricultural Science
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• v.47 no.4
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• pp.941-949
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• 2020

This study evaluated the nutritional value of Italian ryegrass (IRG) as a forage source for Hanwoo. The nutritional value of IRG was assessed and compared to that of rice straw, oat hay, and timothy hay using two different methods: 1) in vitro ruminal fermentation 2) in vivo total tract digestibility. In vitro DM digestibility was lower in rice straw compared to the other three forage sources after both 24 and 48 h of incubation (p < 0.01). Among the four forage sources, IRG had a higher NH3-N concentration after both 24 and 48 h of incubation (p < 0.01). In the in vivo digestibility trials, four different substrates were used: 1) 80% concentrate with 20% rice straw, 2) 80% concentrate with 20% oat hay, 3) 80% concentrate with 20% IRG, and 4) 80% concentrate with 20% timothy hay. The dry matter, crude protein, non-fiber carbohydrate, and detergent fiber digestibility were the greatest in the C80-IRG20 among the four forage groups. In summary, IRG had a similar level of energy efficiency compared to oat hay and timothy hay. Furthermore, the result of the chemical composition analysis showing a higher ammonia concentration in the in vitro fermentation experiment and the high protein digestibility in the in vivo experiment indicate that IRG is a good source of protein compared to oat hay and timothy hay.

• Clinical and Experimental Reproductive Medicine
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• v.48 no.1
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• pp.50-60
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• 2021

Objective: This study investigated the mRNA expression of gamma-aminobutyric acid (GABA) receptors in the sperm of oligoasthenoteratozoospermic (OAT) and teratozoospermic (TER) men compared to normozoospermic (NOR) men, as well as the relationships between GABA receptor expression and sperm parameters, fertilization rate, and embryo quality. Methods: The mRNA expression of GABA A-α1 and GABA B-R2 receptors in sperm was examined using reverse transcription-polymerase chain reaction in three groups of patients: NOR (n=32), OAT (n=22), and TER (n=45). The fertilization rate and embryo quality were assessed in 35 patients undergoing intracytoplasmic sperm injection (ICSI; 10 NOR, 10 OAT, and 15 TER men). Results: OAT men had significantly higher mRNA expression of GABA A-α1 and GABA B-R2 receptors in sperm than NOR men; however, the difference between TER and NOR men was not significant. High levels of these receptors were significantly correlated with low sperm concentration, motility, and morphology, as well as the rate of good-quality embryos (GQEs) at the cleavage stage after ICSI. Patients whose female partners had a >50% GQE rate at the cleavage stage had significantly lower levels of GABA A-α1 receptor expression than those whose partners had a ≤50% GQE rate. Conclusion: Our findings indicate that mRNA levels of GABA receptors in human sperm are correlated with poor sperm quality and associated with embryo development after ICSI treatment. The GABA A-α1 receptor in sperm has a stronger relationship with embryo quality at the cleavage stage than the GABA B-R2 receptor.

• Journal of Animal Science and Technology
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• v.63 no.1
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• pp.137-148
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• 2021

The effect of the addition of dietary fiber extracted from wheat, bamboo, and oat on the quality of fried pork loin batter was investigated. Quality evaluation included proximate composition, pH, color, viscosity, coating and frying yield, electronic nose, and sensory evaluation. Regarding proximate composition of fried batter and fried pork loin, the water content of the dietary fiber treatments was significantly higher than that of the control (p < 0.05), whereas fat content was significantly lower than that of the control (p < 0.05). The lightness of non-fried batter with dietary fiber treatments was significantly higher than that of the control (p < 0.05), whereas the yellowness was significantly lower than that of the control (p < 0.05). The lightness, redness, and yellowness of fried pork loin with dietary fiber treatment were significantly lower than those of the control (p < 0.05). The viscosity and coating and frying yield of dietary fiber treatments were significantly higher than those of the control (p < 0.05). The volatile compounds of dietary fiber treatments were decreased "tallowy" flavor and increased "buttery" and "milky" flavor. The principal components of bamboo and oat fiber treatments were clearly distinguishable from those of the control; however, similar principal components as those of the control were obtained with wheat fiber treatment. Regarding sensory evaluation, the color, texture, and overall acceptability of wheat and oat fiber treatments were significantly higher than those of the control (p < 0.05), and the flavor of the wheat fiber treatment was significantly higher than that of the control (p < 0.05). These results show that wheat and oat fibers are suitable for fried pork loin batter and improve its quality.