• Wind and Structures
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• v.34 no.1
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• pp.127-136
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• 2022

In this work a multi-fidelity non-intrusive polynomial chaos (MF-NIPC) has been applied to a structural wind engineering problem in architectural design for the first time. In architectural design it is important to design structures that are safe in a range of wind directions and speeds. For this reason, the computational models used to design buildings and bridges must account for the uncertainties associated with the interaction between the structure and wind. In order to use the numerical simulations for the design, the numerical models must be validated by experi-mental data, and uncertainties contained in the experiments should also be taken into account. Uncertainty Quantifi-cation has been increasingly used for CFD simulations to consider such uncertainties. Typically, CFD simulations are computationally expensive, motivating the increased interest in multi-fidelity methods due to their ability to lev-erage limited data sets of high-fidelity data with evaluations of more computationally inexpensive models. Previous-ly, the multi-fidelity framework has been applied to CFD simulations for the purposes of optimization, rather than for the statistical assessment of candidate design. In this paper MF-NIPC method is applied to flow around a rectan-gular 5:1 cylinder, which has been thoroughly investigated for architectural design. The purpose of UQ is validation of numerical simulation results with experimental data, therefore the radius of curvature of the rectangular cylinder corners and the angle of attack are considered to be random variables, which are known to contain uncertainties when wind tunnel tests are carried out. Computational Fluid Dynamics (CFD) simulations are solved by a solver that employs the Finite Element Method (FEM) for two turbulence modeling approaches of the incompressible Navier-Stokes equations: Unsteady Reynolds Averaged Navier Stokes (URANS) and the Large Eddy simulation (LES). The results of the uncertainty analysis with CFD are compared to experimental data in terms of time-averaged pressure coefficients and bulk parameters. In addition, the accuracy and efficiency of the multi-fidelity framework is demonstrated through a comparison with the results of the high-fidelity model.

• Journal of the Korean Chemical Society
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• v.65 no.6
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• pp.433-440
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• 2021

Surfactants are organic compounds that have both hydrophilic and non-polar parts in one molecule, classified as non-ion, anion, cation, and amphoteric surfactants according to the charge of hydrophilic parts in aqueous state. A trace amounts may remain when vegetables and fruits are washed using type1 detergent (Vegetable and fruit detergent), and there is a possibility of exposure to the human body through ingestion. This study developed the simultaneous analysis method for 5 surfactants with LC-MS/MS for analysis of detergent residues after washing vegetables and fruits with detergent. The mobile phase used distilled water and acetonitrile containing 50 mM ammonium formate and 0.1% formic acid and was analyzed using a gradient method using XBridge BEH C8 column. The accuracy of the established method was 83.9-112.1%, and the precision was less than 20%. The detection limit was 7.0 (SLS) to 29.0 (SLES-N3) ㎍/L, and the correlation coefficient (r²) of calibration line regression was greater than 0.99, it is considered suitable for the analysis of trace amounts of surfactant components remaining in vegetables and fruits.

• KOREAN JOURNAL OF CROP SCIENCE
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• v.46 no.6
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• pp.459-463
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• 2001

Changes of rice yield and soil physicochemical properties of the dry-seeded rice-barley double cropping system were investigated for 10 years from 1990 to 1999. Generally, seedling stand was more unstable in the rice-barley cropping system regardless of barley straw addition or removal than in the rice single cultivation as indicated by higher standard deviation of seedling stand across year. Rice yield in rice-barley double cropping cultivation was increased due to barley straw application starting from the second year, recording 2 to 19％ increase (average of 9％ for 10 years) due to higher spikelet number. Protein content and Mg/K equivalent ratio were similiar among the barley straw applied field, rice single crop and barley straw removed plots. Also, amylose content was not significantly different among cropping patterns. Physicochemical properties of soil was improved by applying the barley straw; soil porosity was higher and content of organic matter and cation exchange capacity of Ca increased but those of Mg and K did not differ.

• KOREAN JOURNAL OF CROP SCIENCE
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• v.41 no.5
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• pp.600-607
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• 1996

Colored rices have been used for specific purposes by rice consumers due to the color and nutritive values empirically recognized. In this study, varietal variations of pigmentation and nutritive values were investigated in brown, red, purple and black rices. Pigments were localized in seed coat to pericarp region in all varieties tested. Pigments were slightly residued on the surface of milled rice. Anthocyanin content per g brown rice was 1.63~17.62 $\mu\textrm{g}$ in brown and reddish-brown rices, 3.56~11.10 $\mu\textrm{g}$ in red rices, 28.11~401.22 $\mu\textrm{g}$ in purple rices, and 3, 665.98 $\mu\textrm{g}$ in a black rice. A vatiety DZ 78 showed the highest protein content out of colored rices analyzed for protein. Normal and colored rices were found to have the similiar composition of amino acids, and so was in between brown rice without embryo and milled rice. Colored rices, L $K_1$B-4-12-1-1 and DK 1, showed higher content of vitamin $B_1$ compared with Hwacheongbyeo, a check variety of no specific color, and L $K_1$B-2-1-1 and L $K_1$B-4-12-1-1 showed much higher content of vitamin B2 in brown rice without embryo. Cation contents such as $K^{+}$, $Mg^{2+}$, $Ca^{2+}$ and F $e^{2+}$ were significantly increased in most of the colored rices tested implying that the increase might be associated with color pigmentation.ation.

• The Journal of Korean Obstetrics and Gynecology
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• v.22 no.1
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• pp.1-14
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• 2009

Purpose: Oxidative stress was thought to play a critical role in neurodegenerative disease. Many in vivo and in vitro reports explained the possible pathway of human aging. But in therapeutic aspects, there was no clear answers to prevent aging associated with neural diseases. In this study, we investigated the antioxidant and neuroprotective effects of the Insamyangyung-tang (IYT). Methods: To estimate the antioxidant effects, we carried out 1.1-diphenyl-2-picrylhydrazyl (DPPH) free radical scavenging assay, 2,2'-azinobis-(3- ethylbenzothiazoline-6- sulfonic acid (ABTS) radical cation decolorization assay, and measurement of total polyphenolic content. To evaluate neuroprotective effect of IYT in vitro. We performed thiazolyl blue tetrazolium bromide (MTT) assay, reactive oxygen species (ROS) creation in SH-SY5Y. Tyrosine hydroxylase (TH) immunocytochemistry, nitric oxide (NO) assay, and TNF-${\alpha}$ assay in primary rat mesencephalic dopaminergic neurons. Results: The $IC_{50}$ values were $571.6{\mu}g/m{\ell}$ and $202.3{\mu}g/m{\ell}$ in DPPH and ABTS assay respectively. Total polyphenolic content was 1.05%. In SH-SY5Y culture, IYT significantly increased the decreased cell viability by 6-OHDA at the concentrations of $10{\mu}g/m{\ell}$ in pre-treatment group, $10-100{\mu}g/m{\ell}$ in post-treatment group, and $100{\mu}g/m{\ell}$ in co-treatment group. The production of ROS induced by 6-OHDA was significantly inhibited in IYT treated group. In mesencephalic dopaminergic cell culture, the IYT group reduced the dopaminergic cell loss against 6-OHDA toxicity and the production of No and TNF-${\alpha}$ at the concentration of $0.2{\mu}g/m{\ell}$. Conclusion: These results showed that IYT has antioxidant and neuroprotectctive effects in the dopaminergic cells through decreasing the production of ROS, NO and TNF-${\alpha}$ which can cause many neurodegenerative changes in brain cell.

• Analytical Science and Technology
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• v.19 no.5
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• pp.441-448
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• 2006

11-nor-9-carboxy-${\Delta}^9$-tetrahydrocannabinol (THCCOOH) is the major metabolite of tetrahydrocannabinol (THC) which is the primary psychoactive component of marijuana. It is also the target analyte for the discrimination marijuana use. A method using solid-phase extraction (SPE) and gas chromatography/mass spectrometry (GC/MS) was developed for the determination of THCCOOH in human urine. Urine samples (3 mL) were extracted by SPE column with a cation exchange cartridge after basic hydrolysis. The eluents were then evaporated, derivatized, and injected into the GC/MS. The limits of detection (LOD) and quantitation (LOQ) were 0.4 and 1.2 ng/mL, respectively. The response was linear with a correlation coefficient of 0.999 within the concentration range of 1.2 (LLE 1.3)~50.0 ng/mL. The precision and accuracy were stable within 1.20% and the recovery was 83.6~90.7%. The recovery of SPE method was lower than that of liquid-liquid extraction (LLE), but there were no apparent differences in LOD, LOQ, precision and accuracy between the two methods. While SPE method is used as a very effective and rapid procedure for sample pretreatment, and clean extracts, LLE method was not suitable for the extraction procedure of THCCOOH in urine. The applicability of the method was proven by analyzing a urine samples from a marijuana abusers.

• Analytical Science and Technology
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• v.21 no.5
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• pp.412-423
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• 2008

A procedure based on solid-phase extraction (SPE) followed by liquid chromatography-tandem mass spectrometry has been developed for the simultaneous analysis of 55 basic drugs in equine urine. The test scope covers diversified classes of drugs including some ${\beta}$-blockers, ${\beta}$-agonists, antihypotensives, CNS stimulants, sedatives, tranquilizers, antidepressants, antihypertensives and so on. LC-MS/MS separation and quantification was carried out in positive electrospray ionization and multiple reaction monitoring (MRM) mode. Four different brands of mixed mode cation exchange SPE sorbents; UCT XTRACT$^{(R)}$ XRDAH, Supelco DSC-MCAX$^{(R)}$, Varian Bond Elut Certify$^{(R)}$ and Waters Oasis$^{(R)}$ MCX were compared. The UCT XTRACT$^{(R)}$ XRDAH sorbent provided the best results in the preconcentration of samples, yielding relative recoveries higher than 80% except for terbutaline (41.3%), salbutamol (71.5%), heptaminol (70.7%), phenylpropanolamine (66.3%). Detection limits of the target drugs provided by the proposed analytical procedure were between 0.2~8.3 ng/mL.

• The Korean Journal of Physiology and Pharmacology
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• v.27 no.4
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• pp.417-426
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• 2023

The TRPM4 gene encodes a Ca²⁺-activated monovalent cation channel called transient receptor potential melastatin 4 (TRPM4) that is expressed in various tissues. Dysregulation or abnormal expression of TRPM4 has been linked to a range of diseases. We introduced the hemagglutinin (HA) tag into the extracellular S6 loop of TRPM4, resulting in an HA-tagged version called TRPM4-HA. This TRPM4-HA was developed to investigate the purification, localization, and function of TRPM4 in different physiological and pathological conditions. TRPM4-HA was successfully expressed in the intact cell membrane and exhibited similar electrophysiological properties, such as the current-voltage relationship, rapid desensitization, and current size, compared to the wild-type TRPM4. The presence of the TRPM4 inhibitor 9-phenanthrol did not affect these properties. Furthermore, a wound-healing assay showed that TRPM4-HA induced cell proliferation and migration, similar to the native TRPM4. Co-expression of protein tyrosine phosphatase, non-receptor type 6 (PTPN6 or SHP1) with TRPM4-HA led to the translocation of TRPM4-HA to the cytosol. To investigate the interaction between PTPN6 and tyrosine residues of TRPM4 in enhancing channel activity, we generated four mutants in which tyrosine (Y) residues were substituted with phenylalanine (F) at the N-terminus of TRPM4. The YF mutants displayed properties and functions similar to TRPM4-HA, except for the Y256F mutant, which showed resistance to 9-phenanthrol, suggesting that Y256 may be involved in the binding site for 9-phenanthrol. Overall, the creation of HA-tagged TRPM4 provides researchers with a valuable tool to study the role of TRPM4 in different conditions and its potential interactions with other proteins, such as PTPN6.

• The Korean Journal of Zoology
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• v.23 no.3
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• pp.125-136
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• 1980

The purpose of the present study is to investigate the electrophoretic patterns of ADH isozymes and activity at various developmental stages of Oregon-R and Kwangju strains of D. melanogaster. The ADH isozymes were seperated by agarose gel plate eletrophoresis and they were stained for ADH activity study. The optical density was measured by using densitometer and the total activity was determined by measuring the enzyme solution's absorbance of 340 nm by spectrophotometer. The results are as follows: 1. At egg stages of Oregon-R and Kwangju strains ADH 2, ADH 3, ADH 4 were observed in te zymograms, but all of ADH 1, ADH 2, ADH 3, ADH 4 and ADH 5 were detected in larval, pupal and imaginal stages. 2. The amount of ADH 1+ADH 2 (anion) was 20-40% and that of ADH 3+ADH 4+ADH 5 (cation) was 60-805. In the developmental stages other, than egg stages, ADH 3 of both strains showed the largest amount among all ADH isozymes, and especially ADH 4 of Kwangju strain showed less amount than that of Oregon-R strain. 3. The total activity of the ADH at the egg stage was found to be the lowest, at larval stage became to be higher and to be lower at pupal stage and then became to be the highest at the imaginal stage. It is noticeable that the activity of the ADH in Kwangju strain was higher than that in Oregon-R strain.

• Korean Journal of Materials Research
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• v.33 no.11
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• pp.465-474
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• 2023

The effects of La³⁺ substitution for Sr²⁺-site on the crystal structure and the dielectric properties of (Ba_0.7Sr_0.3-3x/2La_x) (Ti_0.9Zr_0.1)O₃ (BSLTZ) (0.005 ≤ x ≤ 0.02) ceramics were investigated. The structural characteristics of the BSLTZ ceramics were quantitatively evaluated using the Rietveld refinement method from X-ray diffraction (XRD) data. For the specimens sintered at 1,550 ℃ for 6 h, a single phase with a perovskite structure and homogeneous microstructure were observed for the entire range of compositions. With increasing La³⁺ substitution (x), the unit cell volume decreased because the ionic size of La³⁺ (1.36 Å) ions is smaller than that of Sr²⁺ (1.44 Å) ions. With increasing La³⁺ substitution (x), the tetragonal phase fraction increased due to the A-site cation size mismatch effect. Dielectric constant (ε_r) increased with the La³⁺ substitution (x) due to the increase in tetragonality (c/a) and the average B-site bond valence of the ABO₃ perovskite. The BSLTZ ceramics showed a higher dielectric loss due to the smaller grain size than that of (Ba_0.7Sr_0.3)(Ti_0.9Zr_0.1)O₃ ceramics. BSLTZ (x = 0.02) ceramics met the X7R specification proposed by the Electronic Industries Association (EIA).