• Journal of the Korean Society of Radiology
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• v.10 no.5
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• pp.367-373
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• 2016

This study conducted an analysis to compare the differences in the properties of the magnetic field and the generation of artifacts because of the difference in the magnetic field between 1.5 T equipment and 3.0 T equipment, centering around four types of pulse sequences, mainly applied to the abdominal Magnetic Resonance Imaging (MRI). With data on 500 persons transmitted to the PACS, this study analyzed the SNR value, quantitatively and carried out a qualitative evaluation, dividing MSA, CSA, and DA into three steps. As a result of the quantitative evaluation, the SNR value was significantly higher in the 1.5 T equipment; however, there was a factor deteriorating the image quality, too, as artifacts were generated in the images. The 1.5 T equipment generated fewer artifacts than the 3.0 T equipment did, so it could compensate the image quality for 3.0 T. In conclusion, based on these findings, this study could understand the differences in the properties of the magnetic field and the generation of artifacts occurring because of the difference in the magnetic field and could provide a measure for them. This study would be guidelines for MRI users who directly examine the patients in abdominal MRI using the two types of equipment in the clinical setting in the future.

• Journal of the Korean Society of Radiology
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• v.17 no.7
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• pp.1123-1131
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• 2023

This study aimed to present a method to effectively suppress metal artifacts caused by spinal fusion surgery during spinal MRI study. For this purpose, a phantom made of spinal surgery screws was created to reproduce the metal artifact. Then, images were acquired with 1.5T and 3.0T MRI to evaluate changes in metal artifacts according to magnetic field strength. In addition, metal artifacts were evaluated by increasing the receive bandwidth to 200, 400 and 800 Hz/PX. As a result, metal artifacts occurring in images obtained from the 1.5T MRI decreased by approximately 52.2% compared to images obtained from the 3.0T MRI, showing a significant difference (p<0.05). In particular, the signal loss and signal pile up areas were reduced by approximately 52.81% and 42.71%, respectively, showing a significant effect in suppressing metal artifacts. On the other hand, when images were acquired while increasing the receive bandwidth from 200 to 800 Hz/PX, there was no significant effect, with a decrease of up to 8.93% for the 1.5T MRI and up to 10.98% for the 3.0T MRI (p>0.05). As a result of this study, increasing the receive bandwidth reduced signal loss and reduced some metal artifacts, but did not have a significant effect because it did not suppress signal pile up. However, when the magnetic field strength was reduced from 3.0T to 1.5T, signal loss and signal pile up were greatly reduced, effectively improving the metal artifact. Therefore, in order to suppress metal artifacts caused by spinal fusion surgery, study using a low magnetic field MRI can be said to be the most effective method.

• Journal of radiological science and technology
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• v.26 no.2
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• pp.57-61
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• 2003

The purpose of this study is to compare both 1.5T and 4.7T in Praietal White matter material Phantom using the same methodology at both field strengths. Data at both field strengths are compared in terms of $T_2$ relaxation times, line widths and SNRs MR imaging and $^1H$ MR spectroscopy were performed on GE 1.5T SIGNA system and Broker Biospec 4.7T/30 MRI/MRS system. After phantom axial scan $^1H$ MRS was obtained from T2 weighted image by 3-dimensional localization technique(PRESS : Point RE solved spectroscopy Sequence) this phantom is composed of an aqueous solution 36.7 mmol/L of NAA, 25.0 mmol/L of Cr, 6.3 mmol/L of choline chloride, 30.0 mmol/L or Glu, and 22.5 mmol/L of MI(adjusted to a pH of 7,15 in a phosphate buffet). Data processed using software developed inhouse. At 1.5T, T2 relaxation times for Cho, Cr, and NAA were $0.41{\pm}0.07,\;0.26{\pm}0.04,\;0.46{\pm}0.07$ while at 4.7T they were $0.17{\pm}0.03,\;0.14{\pm}0.05,\;0.20{\pm}0.03$ respectively. At 1.5T, line widths for water, Cho, Cr and NAA were $2.9{\pm}0.7,\;1.6{\pm}0.7,\;1.7{\pm}0.8,\;2.2{\pm}0.02Hz$ while at 4.7T they were $5.2{\pm}1.1,\;4.6{\pm}1.9,\;4.01{\pm}1.8,\;4.8{\pm}1.9Hz$ respectively. It can be seen that $T_2$ relaxation times were significantly shorter at 4.7 compared to 1.5T and that the line widths were also broader. The average SNRs for NAA for subjects at short and long TEs were $23.5{\pm}11.3$ at TE=20 msec ; $15.4{\pm}7.7$ at TE=272 msec at 1.5T and $40{\pm}8.3$ and $17{\pm}3.5$ respectively at 4.7T higher field strength is superior because of improved sensitivity and chemical shift dispersion. However these improvements are partially offset by increased line widths and decrease $T_2$ relaxation times, which act to reduce both sensitivity and resolution. In our experiments with the equipment available to us, 4.7T proton spectra at short TEs exhibit moderately improved sensitivity compared to 1.5T.

• Proceedings of the Korean Magnestics Society Conference
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• 1998.10a
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• pp.102-103
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• 1998

• Asian-Australasian Journal of Animal Sciences
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• v.26 no.11
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• pp.1569-1576
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• 2013

The study was conducted to evaluate the effect of vitamin E and zinc supplementation on energy metabolites, lipid peroxidation, and milk production in peripartum Sahiwal cows. For this, thirty-two pregnant dry Sahiwal cows were selected at sixty days prepartum and divided into four groups viz control, $T_1$, $T_2$, and $T_3$ of eight each. Group $T_1$ were supplemented with zinc at 60 ppm/d/cow, group $T_2$ were supplemented with vitamin E at 1,000 IU/d/cow and group $T_3$ were supplemented with combination of vitamin E at 1,000 IU/d/cow and zinc at 60 ppm/d/cow during d 60 prepartum to d 90 postpartum. Blood samples were collected on d -60, -45, -30, -15, -7, -3, 0, 3, 7, 15, 30, 45, 60, 90, and 120 with respect to day of parturition and analysed for glucose, non esterified fatty acid, and thiobarbituric acid reactive substance. Body condition score was maintained significantly better (p<0.05) in $T_3$ than in the control, $T_1$ and $T_2$ groups. Overall glucose level was higher (p<0.05) in $T_3$ than control, $T_1$, and $T_2$ groups. Levels of nonesterified fatty acid, and thiobarbituric acid reactive substance were lower (p<0.05) in $T_3$ than control, $T_1$, and $T_2$ groups. Milk yield was higher (p<0.05) in $T_3$ than control, $T_1$, and $T_2$ groups. In conclusion, the present study indicated that the supplementation of vitamin E and zinc in peripartum Sahiwal cows enhanced milk production by reducing negative energy balance.

• Journal of Animal Science and Technology
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• v.49 no.5
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• pp.657-666
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• 2007

This study was conducted to evaluate the effects of dietary addition of caprylic acid(CA)-cyclodextrin (CD) complex on in vitro fermentation characteristics, total gas and methane production. Experiment was done with six treatment groups; 1) no CA-CD complex(control), 2) CA 20 mg(T1), 3) CD 830 mg(T2), 4) CA-CD complex 425 mg(T3), CA-CD complex 850mg(T4), CA-CD complex 1,700 mg(T5). Ruminal pH, ammonia and total VFA concentrations of T2, T3, T4 and T5 were lower(P<0.05) than those of control and T1 for the 12h incubation. The increase in molar percentage of propionate was observed in T4 and T5 compared with control and T2 for the 8h incubation(P<0.05), however, the ratio of acetate to propionate was unchanged in all treatments. Total gas of T1 was lower than that of control, but T2, T3, T4 and T5 were higher compared with control for 12h incubation(P<0.05). If the methane ratio (as %) to total gas for all treatments was compared, T3, T4 and T5(CA-CD supplemented groups) averaged 2.7% whereas control, T1 and T2 showed 3.4, 2.8 and 5.1%, respectively. Therefore, according to these results, it might be concluded that supplementation of CA-CD complex could reduce methane production without disrupting ruminal fermentation.

• Journal of The Korean Society of Grassland and Forage Science
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• v.42 no.4
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• pp.215-221
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• 2022

This study was carried out to investigate the growth characteristics, yield and chemical compositions of rye according to mixing ratio of chemical fertilize r(CF) and liquid swine manure (LSM) in paddy field cultivation. The experimental design was arranged in a randomized block design with three replications. The manure fertilizer ratio of five treatments were CF 100% + LSM 0% (C), CF 70% + LSM 30% (T1), CF 50% + LSM 50% (T2), CF 30% + LSM 70% (T3), and CF 0% + LSM 100% (T4) of rye. At this time, the application of liquid swine manure was based solely on nitrogen. Plant length did not show significant differences among treatments. Ear length, leaf length and leaf width were the longest in C, T3, and T2, respectively (p<0.05). The stem diameter showed in the order of T4 > T3 > T2 > T1 > C, which was thicker as the LSM application rate increased (p<0.05). Fresh, dry matter and total digestible nutrient (TDN) yield were the highest in T4 (p<0.05), whereas the lowest in C treatment. Crude protein, neutral detergent fiber (NDF), acid detergent fiber (ADF) and crude fiber content were did not show significant difference among treatments. However, compared to C, crude fat and crude ash were significantly higher in T2 and T3, respectively (p<0.05). Total mineral content decreased significantly as the LSM application rate increased (p<0.05). Total free sugar showed high in T3 and T4 with a high LSM ratio, but showed significantly lower in chemical fertilizer treatment (C) and low LSM treatment (T1) (p<0.05). The analysis of all the above results suggests that the application of LSM is very effective, considering the dry matter yield and the contents of free sugar. In addition, LSM may be possible to grow rye without chemical fertilizer.

• Asian-Australasian Journal of Animal Sciences
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• v.11 no.6
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• pp.702-707
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• 1998

An experiment was conducted to evaluate the effect of a microbial enzyme (Roxazyme-$G^{(R)}$), a multicarbohydrases preparation, supplementation to the wheat-based layer diets. Diets were formulated to include different levels of wheat replacing yellow corn on isocaloric and isonitrogenous basis. The energy value of wheat in the enzyme supplemented diets was adjusted (spec-modified) to have 5% more ME than the wheat in diets without enzyme. A total of 864 Hy-$Line^{(R)}$ brown layers were assigned to 4 dietary treatments: 10% wheat (T1), 25% wheat (T2), 25% wheat (spec-modified)+ 0.01 % Roxazyme-$G^{(R)}$ (T3), and all wheat (spec-modified)+0.01% Roxazyme-$G^{(R)}$ (T4). Hen-day egg productions of T1 and T4 were significantly (p < 0.05) greater than that of T2 but not different from T3. Hen-housed egg production of T4 was significantly (p < 0.01) greater than those of T1 and T3 but not different from T2. Egg weights of T1 and T2 were significantly (p < 0.0 1) greater than that of T4. Feed consumption of T2 was significantly (p < 0.01) lower than other treatments. Feed conversion ratio (feed/egg mass) was not significantly different among treatments. Eggshell thickness of T1 was significantly (p < 0.01) greater than other treatments but ratio of broken eggs was not significantly different among treatments. Haugh unit of T4 was significantly greater (p < 0.05) than that of T2. Egg yolk color was significantly (p < 0.01) influenced by treatments in which enzyme treatment potentiated the yolk pigmentation. It was concluded that a multi-carbohydrases supplementation enables complete replacement of yellow com with wheat without loss of productivity and major egg quality parameters.

• Korean Journal of Soil Science and Fertilizer
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• v.47 no.6
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• pp.571-578
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• 2014

The garlic cultivation area is moved by change of grown environment due to global warming. It is important to predict changes in cultivation area, quantity and quality of each crop. This study was carried out to estimate the yield and response of garlic growth by the rapid temperature changes in the greenhouse with thermostat control system. Seedlings of Namdo garlic were planted on September 27, 2012 and harvested on May 30, 2013. The used treatments for a rapid temperature change in March-April-May were T0 (control): $6.0-10.4-17.2^{\circ}C$, T1: $6.0-5.4(-5)-17.2^{\circ}C$, T2: $6.0-10.4-22.2(+5)^{\circ}C$ and T3: $6.0-5.4(-5)-22.2(+5)^{\circ}C$. Total dried weight per plant of garlic significantly increased by 5.0% for T2, but T1 and T3 decreased by 12.5 and 4.6%, respectively, compared to T0. Total yields of bulb within the temperature change as T2 and T0 increased significantly (p<0.05), as compared to T1. Decreasing temperature significantly (p<0.05) reduced plant height, SPAD reading, crude protein and fiber contents etc., as compared to T0 and T2. ABA contents gradually increased with time but IAA content rapidly decreased. Conclusively, growth and yield of garlic were more affected by decreased temperature than increased temperature at bulb development stage.

• Korean journal of applied entomology
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• v.53 no.3
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• pp.247-260
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• 2014

To identify the species of Trichogramma occurring in the corn fields of Korea as egg parasitoids of Ostrinia furnacalis, we sequenced the full-length of ITS2 nuclear rDNA from 112 parasitoids collected during this study. As a reference to distinguish species, we also retrieved full-length ITS2 sequences of 60 Trichogramma species from the NCBI GenBank database. On the basis of the size and 3'terminal sequence pattern of the ITS2 sequences, the Trichogramma samples collected in this study were divided into three groups (K-1, -2, and -3). Evolutionary distances (d) within and between groups based on ITS2 sequences were estimated to be ${\leq}0.005$ and ${\geq}0.080$, respectively. In the net average distance between groups or species, the d value between K-1 and T. ostriniae, K-2 and T. dendrolimi, and K-3 and T. confusum was the lowest, with values of 0.016, 0.001, and 0.002, respectively. In the phylogenetic tree, K-1 and K-2 were clustered with T. ostriniae and T. dendrolimi, respectively. However, K-3 was clustered with three different species, namely, T. confusum, T. chilonis, and T. bilingensis. NCBI BLAST results revealed that parasitoids belonging to K-1 and K-2 showed 99% identity with T. ostriniae and T. dendrolimi, respectively. Parasitoids in K-3 collected from Hongcheon showed 99-100% identity with T. confusum and T. chilonis, and one parasitoid in K-3 collected from Gochang had 98% identity with T. bilingensis, T. confusum, and T. chilonis. On the basis of these results, we infer that the species of Trichogramma collected in this study are closely related to T. ostriniae (K-1) and T. dendrolimi (K-2). However, it was not possible to distinguish species of K-3 using the ITS2 sequence alone.