• Corrosion Science and Technology
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• v.22 no.1
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• pp.64-72
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• 2023

Ni-Ti shape memory alloy for dental nerve treatment devices was prepared by adding Mo to Ni-Ti alloy to improve flexibility and fatigue fracture characteristics and simultaneously increase corrosion resistance. Surface properties of the alloy were evaluated. Microstructure analysis of the Ni-Ti-xMo alloy revealed that the amount of needle-like structure increased with increasing Mo content. The shape of the precipitate showed a pattern in which a long needle-like structure gradually disappeared and changed into a small spherical shape. As a result of XRD analysis of the Ni-Ti-xMo alloy, R-phase structure appeared as Mo was added. R-phase and B2 structure were mainly observed. As a result of DSC analysis, phase transformation of the Ti-Ni-Mo alloy showed a two-step phase change of B2-R-B19' transformation with two exothermic peaks and one endothermic peak. As Mo content increased, R-phase formation temperature gradually decreased. As a result of measuring surface hardness of the Ti-Ni-Mo alloy, change in hardness value due to the phase change tended to decrease with increasing Mo content. As a result of the corrosion test, the corrosion potential and pitting potential increased while the current density tended to decrease with increasing Mo content.

• Animal Bioscience
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• v.37 no.7
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• pp.1289-1302
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• 2024

Objective: There is a strong relationship between the content of beneficial fatty acids in milk and milk fat metabolic activity in the mammary gland. To improve milk quality, it is therefore necessary to study fatty acid metabolism in bovine mammary gland tissue. In adipose tissue, peroxisome proliferator-activated receptor gamma (PPARG), the core transcription factor, regulates the fatty acid metabolism gene network and determines fatty acid deposition. However, its regulatory effects on mammary gland fatty acid metabolism during lactation have rarely been reported. Methods: Transcriptome sequencing was performed during the prelactation period and the peak lactation period to examine mRNA expression. The significant upregulation of PPARG drew our attention and led us to conduct further research. Results: According to bioinformatics prediction, dual-luciferase reporter system detection, real-time quantitative reverse transcription polymerase chain reaction and Western blotting, miR-130a and miR-130b could directly target PPARG and inhibit its expression. Furthermore, triglyceride and oil red O staining proved that miR-130a and miR-130b inhibited milk fat metabolism in bovine mammary epithelial cells (BMECs), while PPARG promoted this metabolism. In addition, we also found that the coexpression of miR-130a and miR-130b significantly enhanced their ability to regulate milk fat metabolism. Conclusion: In conclusion, our findings indicated that miR-130a and miR-130b could target and repress PPARG and that they also have a functional superposition effect. miR-130a and miR-130b seem to synergistically regulate lipid catabolism via the control of PPARG in BMECs. In the long-term, these findings might be helpful in developing practical means to improve high-quality milk.

• Korean Journal of Radiology
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• v.22 no.9
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• pp.1537-1546
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• 2021

Objective: To assess the role of arterial spin-labeling (ASL) perfusion MRI in identifying cerebral perfusion changes after indirect revascularization in children with moyamoya disease. Materials and Methods: We included pre- and postoperative perfusion MRI data of 30 children with moyamoya disease (13 boys and 17 girls; mean age ± standard deviation, 6.3± 3.0 years) who underwent indirect revascularization between June 2016 and August 2017. Relative cerebral blood flow (rCBF) and qualitative perfusion scores for arterial transit time (ATT) effects were evaluated in the middle cerebral artery (MCA) territory on ASL perfusion MRI. The rCBF and relative time-to-peak (rTTP) values were also measured using dynamic susceptibility contrast (DSC) perfusion MRI. Each perfusion change on ASL and DSC perfusion MRI was analyzed using the paired t test. We analyzed the correlation between perfusion changes on ASL and DSC images using Spearman's correlation coefficient. Results: The ASL rCBF values improved at both the ganglionic and supraganglionic levels of the MCA territory after surgery (p = 0.040 and p = 0.003, respectively). The ATT perfusion scores also improved at both levels (p < 0.001 and p < 0.001, respectively). The rCBF and rTTP values on DSC MRI showed significant improvement at both levels of the MCA territory of the operated side (all p < 0.05). There was no significant correlation between the improvements in rCBF values on the two perfusion images (r = 0.195, p = 0.303); however, there was a correlation between the change in perfusion scores on ASL and rTTP on DSC MRI (r = 0.701, p < 0.001). Conclusion: Recognizing the effects of ATT on ASL perfusion MRI may help monitor cerebral perfusion changes and complement quantitative rCBF assessment using ASL perfusion MRI in patients with moyamoya disease after indirect revascularization.

• Korean Journal of Food Science and Technology
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• v.32 no.3
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• pp.500-506
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• 2000

The effects of sodium stearoyl lactylate(SSL) on the thermal properties of wheat starch and amylopectin, and the crystallinity properties of amylopectin were investigated using differential scanning calorimetry(DSC) and X-ray diffractometer. On the rescan(second heating), amylopectin produced the featureless thermogram shown at the second heating, and SSL alone melted at $40{\sim}55^{\circ}C$, while the mixture of amylopectin containing 8% water and SSL(10:1), presenting the evidence of AP-SSL complex, showed differentiate melting temperature(other crystallinity) from SSL alone. Also, the melting enthalpy of AP and SSL mixture by subsequent heating and cooling were continuously increased. Further, the mixtures of wheat starch: SSL (5:1, w/w) and amylopectin: SSL(5:1, w/w), indicated AP-SSL complex, showed the reversible melting peak at temperature range of $60{\sim}70^{\circ}C$ together with melting peak of SSL observed at temperature range of $40{\sim}55^{\circ}C$. AP-SSL complex in the X-ray diffraction, compared V-form of amylose-lipid complex, exhibited characteristic peaks($2{\theta}$, 5.57, 20.903, 23.227). The gelatinization enthalpy value of wheat starch in the presence of SSL, observed at temperature range of $50{\sim}70^{\circ}C$, was decreased at total water content 60%, whearas had no significant effect at total water content 40, 50%, and also, SSL increased melting enthalpy of amylose-lipid complex. The extent of AP and wheat starch retrogradation wasreduced significantly by SSL.

• Journal of Korean Society of Environmental Engineers
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• v.31 no.9
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• pp.803-810
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• 2009

This study is conducted to examine spatial variations of Dissolved Organic Matter (DOM) in stream and waste waters of the different watershed areas (agricultural, residential, and industrial complex area) by using fluorescence 3D-EEMs (3 Dimensional Excitation Emission Matrix Spectroscopy). Furthermore, the research investigates the changes of DOM characterization by synchronous and 3D-EEMs during a rainfall event. The characterizations of DOM obtained by 3D-EEMs show two noticeable peaks at humic and protein-like regions. Humic-like substances (HLS) are found in rural and urban areas, and humic and protein-like substances (PLS) are shown in industrial area. According to the fluorescence peak $T_1:C_1$ ratios, it is observed that high amount of HLS was discharged from Banweol Industrial Complex (3TG). Additionally, linear relationships (Regression rate, $r^2$=0.65, $r^2$=0.66) have been shown between PLS (peak $T_1,\;B_1$) and biochemical oxygen demand (BOD), which indicates the impact of sewage. For the rainfall event (30 mm), no remarkable difference of DOM was found at rural area except increment of fluorescence intensity comparing dry period. In contrast, HLS at urban area is highly discharged within 30 minutes from the beginning of rainfall. Also, there are high influences of HLS and PLS within 20 minutes at industrial complex (4TG). Fluorescence 3D-EEMs has not only verifies a watershed of DOM origination but also monitors diffuse and point source impacts.

• Journal of Korean Academy of Fundamentals of Nursing
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• v.1 no.1
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• pp.69-76
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• 1994

This study was designed and undertaken to find out the effectiveness of VAS for evaluation of general anesthetic postoperative pulmonary-function. We compared the degree of perceived pulmonary function recovery with peak expiratory flow at postoperative 72 hours of subjects. The subjects of this study were collected 38 patients who had received upper abdominal operation in St. Paul Hospital, Catholic University Medical College, and Kangnam Scared Heart Hospital and Kangdong Scared Heart Hospital, Hallym University. Data collection period was from June 15th, to August 7th, 1992. The degree of pulmonary recovery function was measured with peak expiratory at 72 hours postoperatively. The degree of perceived pulmonary function of the patient was measured with ten points visual analog scale at 72 hours postoperatively. Peak expiratory flow and visual analog score was analyzed with Pearson correlation. Peak expiratory flow was expressed as a ratio of preoperative value. The result was as follows : The recovery of pulmonary function and the degree of perceived pulmonary function of the patient at 72hours postoperatively was revealed high correlation (r=.84). The above result suggested that patients with general anesthetic upper abdominal surgery should evaluate recovery of pulmonary function making use of VAS. We know that VAS is very useful in postoperative patients. We perceived that VAS is to take up a positive attitude of patients. Nurse should furnish the nursing care objectively and scientifically to patients. As VAS was economic and simple, VAS should be adviced for wider application.

• Journal of Electrical Engineering and Technology
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• v.11 no.1
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• pp.157-166
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• 2016

In this paper, a new sag and peak voltage detector is proposed for a single-phase inverter using delta square operation. The conventional sag detector is from a single-phase digital phase-locked loop (DPLL) that is based on d-q transformations using an all-pass filter (APF). The d-q transformation is typically used in the three-phase coordinate system. The APF generates a virtual q-axis voltage component with a 90° phase delay, but this virtual phase cannot reflect a sudden change in the grid voltage at the instant the voltage sag occurs. As a result, the peak value is drastically distorted, and it settles down slowly. A modified APF generates the virtual q-axis voltage component from the difference between the current and the previous values of the d-axis voltage component in the stationary reference frame. However, the modified APF cannot detect the voltage sag and peak value when the sag occurs around the zero crossing points such as 0° and 180°, because the difference voltage is not sufficient to detect the voltage sag. The proposed algorithm detects the sag voltage through all regions including the zero crossing voltage. Moreover, the exact voltage drop can be acquired by calculating the q-axis component that is proportional to the d-axis component. To verify the feasibility of the proposed system, the conventional and proposed methods are compared using simulations and experimental results.

• Journal of Advanced Navigation Technology
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• v.20 no.6
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• pp.612-616
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• 2016

Gamma-ray must be detected and processed immedietely after generation of it in the circumstances where it exists. Software methology may be used to process randomly generated signals, but its memory size and processing time become large. By the way, the hardware circuit to detect randomly generated signals is generalized in industrial site, while those circuits are not able to answer to the cases whose amplitude are very small and also speed high. We researched and developed hardware based peak-hold circuit that is able to detect peaks of gamma-ray signals through direct reading out their values by ADC at the time of maximum reaching for the small amplitude and high speed signals, and proposed and estimated its results in this paper. This peak-hold circuit is adequate to use in the radiation circumstances in which the gamma-rays are heavy because its circuit can catch high speed signals efficiently without software signal processing supports.

• Asian-Australasian Journal of Animal Sciences
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• v.16 no.9
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• pp.1242-1246
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• 2003

Data pertained to 335 crossbred cows comprising of 1/2 Friesian (F) + 1/2 Hariana (H), 1/2 F + 1/4 Jersey (J) + 1/4 H, 1/2 F + 1/4 Brown Swiss (BS) + 1/4 H, 1/2 F + 1/4 Red Dane (R) + 1/4 H, FR (I) and FRH (I) genetic groups extending over a period of 21 years (1970-1990) maintained at Animal Farm of CCS HAU, Hisar. The averages for first lactation milk yield was $2,486.24{\pm}80.26kg$ and peak yield of first three lactation were $11.35{\pm}0.72kg$, $13.97{\pm}0.60kg$ and $16.02{\pm}0.42kg$, respectively. The lifetime milk production was observed as $11,305.16{\pm}1,004.52kg$ in crossbred cattle. The average first lactation fat yield was observed as $102.06{\pm}0.01kg$ and peak fat yield of first three lactation were $0.458{\pm}0.01$, $0.490{\pm}0.01$ and $0.500{\pm}0.02kg$, respectively. The lifetime fat production was estimated as $502.31{\pm}45.90kg$. LTMP and LTFP had reasonably good additive genetic variance which could be exploited either through mass selection/combined with family or pedigree selection. FLMY, peak yields and LTMP had significant positive phenotypic correlation with FLFY and LTFP and the correlation at the genetic level were also higher and positive for these traits. Finally, peak week milk yield of first lactation (PMY1) was the earliest available trait having desirable and significant correlation at phenotypic and positive at genetic level with FLFY, PFY1 and PFY2, PFY3 and LTFP and selection for this trait will help in early evaluation of sires and dams and will increase genetic advancement per unit of time.

• Magazine of the Korean Society of Agricultural Engineers
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• v.19 no.2
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• pp.4377-4384
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• 1977

The curvilinear hydrograph can be replaced by an equivalent triangular hydrograph which is more easily constructed and, for routing through reservoirs or stream channels, gives results about as accurate as those obtained using the curvilinear hydrograph. A synthetic hydrograph is prepared using the data from a number of watersheds to develop a dimensionless unit hydrograph applicable to ungauged watersheds. The dimensionless unit hydrograph for the NakDong River Basin was prepared from the unit hydrographs of a variety of nine subwatersheds. The equation for the peak rate of flow (unit volume of runoff in 1.0mm) was derived as {{{{ { q}_{p } = { 0.21AR} over { {T }_{p } } }}}} The results summarized in this study are as follows: 1) It found that the watershed lag time (Lg, hrs) could be expressed by Lg=0.253(L.Lca)0.4171 The product L.Lca is a measure of the size and shape of the watershed. Correlation coefficient for Lg was 0.97 which defined with high significance. 2) The base length of the unitgraph, in hours, was adopted as Tb=17.51+2.073Lg with high significant correlation coefficient, 0.92. 3) Time in hour from start of rise to peak rate (TP) generally occured at the position of 0.289 Tb with some indication of higher values for larger watershed. 4) Triangular hydrograph is a dimensionless unitgraph prepared from the 40 unitgraphs. The equation is shown as {{{{ { q}_{p } = { K.A.R} over { { T}_{p } } }}}}. The constant K=0.21 is defined to NakDong River basin. 5) In the light of the results analyzed in this study, average errors in the peak discharge of the Trjangular unitgraph was estimated as 5.34 percent to the peak of observed average unitgraph. Each ordinate of the Triangular unitgraph was approached closely to the observed one.