• BMB Reports
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• v.40 no.1
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• pp.22-28
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• 2007

MyoD, expressed in skeletal muscle lineages of vertebrate embryo, is one of muscle-specific basic helix-loop-helix (bHLH) transcription factors, which plays a key role in the determination and differentiation of all skeletal muscle lineages. In this study, a cDNA of grass carp MyoD was cloned and characterized from total RNA of grass carp embryos by RT-PCR. The full-length cDNA of grass carp MyoD is 1597 bp. The cDNA sequence analysis reveals an open reading frame of 825 bp coding for a protein of 275 amino acids, which includes a bHLH domain composed of basic domain (1-84th amino acids) and HLH domain (98-142th amino acids), without signal peptide. Then the MyoD cDNA of grass carp was cloned to yeast expression vector pPICZ$\alpha$A and transformed into P. pastoris GS115 strain, the recombinant MyoD protein with a molecular weight of about 31KD was obtained after inducing for 2d with 0.5% methanol in pH 8.0 BMGY medium, and the maximum yield was about 250 mg/L in shaking-flask fermentation. The results were expected to benefit for further studies on the crystal structure and physiological function of fish MyoD.

• Molecules and Cells
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• v.41 no.6
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• pp.545-552
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• 2018

Spleen tyrosine kinase (SYK) is a cytosolic non-receptor protein tyrosine kinase. Because SYK mediates key receptor signaling pathways involving the B cell receptor and Fc receptors, SYK is an attractive target for autoimmune disease and cancer treatments. To date, representative oral SYK inhibitors, including fostamatinib (R406 or R788), entospletinib (GS-9973), cerdulatinib (PRT062070), and TAK-659, have been assessed in clinical trials. Here, we report the crystal structures of SYK in complex with two newly developed inhibitors possessing 4-aminopyrido[4,3-D]pyrimidine moieties (SKI-G-618 and SKI-O-85). One SYK inhibitor (SKI-G-618) exhibited moderate inhibitory activity against SYK, whereas the other inhibitor (SKI-O-85) exhibited a low inhibitory profile against SYK. Binding mode analysis indicates that a highly potent SYK inhibitor might be developed by modifying and optimizing the functional groups that interact with Leu377, Gly378, and Val385 in the G-loop and the nearby region in SYK. In agreement with our structural analysis, one of our SYK inhibitor (SKI-G-618) shows strong inhibitory activities on the ${\beta}$-hexosaminidase release and phosphorylation of SYK/Vav in RBL-2H3 cells. Taken together, our findings have important implications for the design of high affinity SYK inhibitors.

• International Journal of Industrial Entomology and Biomaterials
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• v.9 no.2
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• pp.187-191
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• 2004

Actin is a ubiquitous and highly conserved protein found in eukaryotic organisms. In this study, we describe the cDNA cloning and mRNA expression of an actin gene from the mulberry longicorn beetle, Apriona germari. The A. germari actin cDNA is 1524 bp containing a complete 1128 bp open reading frame that encodes a polypeptide of 376 amino acid residues with a predicted molecular weight of about 41.5 kDa. The deduced amino acid sequence of the A.germari actin cDNA showed 99% protein sequence identity to Homalodisca coagulata actin, differing at only two amino acid positions, and 92-98% protein sequence identity to known insect species actins. The predicted three-dimensional structure of A. germari actin revealed the four residue hydrophobic pulg loop characteristic of the actin family. Northern blot analysis showed that A. germari actin is highly expressed in epidermis and muscle, and less strongly in midgut, but not in the fat body of A. germari larva.

• Proceedings of the Korean Vacuum Society Conference
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• 2000.02a
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• pp.163-163
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• 2000

In this research, we used the ion irradiation technique which has an advantae in improving intentionally the properties of surface and interface in a non-equilibrium, instead of the conventional annealing method which has been known to improve the material properties in the equilibrium stat. Cu/Co multilayered films were prepared on SiN4/SiO2/Si substrates by the electron-beam evaporation for the Co layers and the thermal evaporation for the Cu layers in a high vacuum. The ion irradiation with a 80keV Ar+ was carried out at various ion doses in a high vacuum. Hysteresis loops of the films were investigated by magneto-optical polar Kerr spectroscopy at various experimental conditions. The change of atomic structure of the films before and after the ion irradiation was studied by glancing angle x-ray diffraction, and the intermixing between Co and Cu sublayers was confirmed by Rutherford backscattering spectroscopy. The surface roughness and magneto-resistance were measured by atomic force microscopy and with a four-point probe system, respectively. During the magneto-resistance measurement, we changed temperature and the direction of magnetization. From the results of experiments, we found that the change at the interfaces of the Cu/Co multilayered film induced by ion irradiation cause the change of magnetic properties. According to the change in hysteresis loop, the surface inplane component of magnetic easy axis was isotropic before the ion irradiation, but became anisotropic upon irradiation. It was confirmed that this change influences the axial behavior of magneto-resistance. Especially, the magneto-resistance varied in accordance with an external magnetic field and the direction of current, which means that magneto-resistance also shows the uniaxial behavior.

• Journal of Surface Science and Engineering
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• v.34 no.5
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• pp.435-444
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• 2001

WC-( $Ti_{1-x}$ A $l_{x}$) N coatings of constant changing Al concentration were deposited on S45C substrates by high-ionization sputtered PVD method. The Al concentration could be controlled by using evaporation source for Al and fixing the evaporation rate of the metals (i.e, WC- $Ti_{0.86}$A $l_{0.14}$N, WC- $Ti_{0.72}$A $l_{0.28}$N, and WC- $Ti_{0.58}$A $l_{0.42}$N). The corrosion behavior of WC-( $Ti_{1-x}$ A $l_{x}$)N coatings in a deaerated 3.5% NaCl solution was investigated by electrochemical corrosion tests and surface analyses. The measured galvanic corrosion currents between coating and substrate indicated that WC- $Ti_{0.72}$A $l_{0.28}$N coating showed the best resistance of the coating tested. The results of potentiodynamic polarization tests showed that the WC- $Ti_{0.72}$A $l_{0.28}$N coating deposited with 32W/c $m^2$ of Al target revealed higher corrosion resistance. This indicated that the WC- $Ti_{0.72}$A $l_{0.28}$N coating is effective in improving corrosion resistance. In EIS, the WC- $Ti_{0.72}$A $l_{0.28}$N coating showed one time constant loop and increased a polarization resistance of coating ( $R_{coat}$) relative to other samples. Compositional variations of WC-( $Ti_{1-x}$ A $l_{x}$)N coatings were analyzed by EDS and XRD analysis was performed to evaluate the crystal structure and compounds formation behavior. Surface morphologies of the films were observed using SEM and AFM. Scratch test was performed to measure film adhesion strength.strength. adhesion strength.strength.

• Journal of the Korean Ceramic Society
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• v.40 no.7
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• pp.683-689
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• 2003

The cylindrical ${\gamma}$-alumina pellets were prepared using amorphous alumina and pore generating agent. Its were immersed in aqueous solution of the mixture of Fe(NO$_3$)$_3$.9$H_2O$ and $CH_3$COOH, Fe(NO$_3$)$_3$.9$H_2O$ and $CH_3$COOH and HNO$_3$, and Fe(NO$_3$)$_3$.9$H_2O$ and HNO$_3$. The pellets thus were hydrothermally treated at 20$0^{\circ}C$ for 3 h in autoclave, and were investigated morphologies and changes of crystal pore characteristics, $N_2$ adsorption and desorption isotherms, active sites and mechanical strength etc. According to the preparation method, acicular platelet pseudo-boehmite crystals of 0.1~0.3 ${\mu}{\textrm}{m}$ size were transformed into acicular pseudo-boehmite cristals of 0.5~2 ${\mu}{\textrm}{m}$ size having the same crystal structure. When ${\gamma}$-alumina pellets were immersed in aqueous solution of the mixture of Fe(NO$_3$)$_3$.9$H_2O$ and $CH_3$COOH and then were hydrothermally treated, pore volume between 100 $\AA$ and 1000 $\AA$ was increased from 0.34 ㏄/g to 0.86 ㏄/g, and the gap of $N_2$ adsorption and desorption hysteresis loop was decreased due to increasement of pore size. New active site that could adsorb the C-H functional group was created on the catalist. Also, mechanical strength of catalyst was increased from 1.06 ㎫ to 1.36 ㎫.

• Journal of the Korean Magnetics Society
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• v.15 no.3
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• pp.167-171
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• 2005

Detailed aspects of the charge disproportionation (CD) transition for a polycrystalline $La_{1/3}Sr_{2/3}FeO_{2.96}$ were studied with the X-ray diffraction, $M\ddot{o}ssbauer$ spectroscopy, and SQUID magnetometer. The crystal structure was found to be rhombohedral with a space group R/3c. The lattice parameters were $a_R=5.4874\;\AA,\;and\;a_R=60.07^{\circ}$, respectively. $M\ddot{o}ssbauer$ spectra were taken within a wide range of temperature from 4.2 K up to room temperature. In the low temperature region, the spectra were comprised of two superimposed sextets which originated from $Fe^{3+}\;and\;Fe^{5+}$, respectively. This was the antiferromagnetic mixed valence state produced by the charges disproportionated into two different species. In the high temperature region, however, only a singlet from $Fe^{3.6+}$ was observed, indicating that it was a paramagnetic averaged valence state. The CD transition occurred in the temperature range from 175 K to 200 K, in which the two phases coexisted. The origin for the CD transition was explained by the thermally generated fast hopping of electrons. Hysteresis loop showed that there existed a strong antiferromagnetic interaction among magnetic ions. As the temperature increased thru the CD transition temperature, it was very likely that the interaction between $Fe^{3+}\;and\;Fe^{5+}$ was replaced by a more stronger one.

• Journal of the Korean Magnetics Society
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• v.18 no.1
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• pp.24-27
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• 2008

We have prepared $MnFe_2O_4$ nanoparticles with polyol method. The crystallographic and magnetic properties were measured by using X-ray diffraction(XRD), vibrating sample magnetometer(VSM) and $M\"{o}ssbauer$ spectroscopy. The high resolution transmission electron microscope(HRTEM) shows uniform nanoparticle-sizes with $6{\sim}8$ nm. The crystal structure is found to be single-phase cubic spinel with space group of Fd3m. The lattice constant of $MnFe_2O_4$ nanparticles is determined to be $8.418{\pm}0.001{\AA}$. $M\"{o}ssbauer$ spectrum of $MnFe_2O_4$ nanparticles at room temperature(RT) shows a superparamagnetic behavior. In VSM analysis, the diagnosis of the superparamagnetic behavior is also shown in hysteresis loop at RT. $M\"{o}ssbauer$ spectrum at 4.2K shows that the well developed two sextets are with different hyperfine field $H_{hfA}=498$(A-site) and $H_{hfB}=521$(B-site) kOe.

• Journal of the Korean Society of Surveying, Geodesy, Photogrammetry and Cartography
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• v.40 no.4
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• pp.261-273
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• 2022

This study aims to predict the land use demand of Seongnam-city using system dynamics and to simulate the effect of changes in family structure and land use density adjustment policy on land use demand. This study attempted to construct causal loop diagrams and an analysis model. The changes in land use demand over time were predicted through simulation results. As a result of the analysis, as of 2035, an additional supply of 2.08 km² for residential land and 1.36 km² for commercial land is required. Additionally, the current supply area of industrial land can meet the demand. Three policy experiments were conducted by changing the variable values in the basic model. In the first policy experiment, it was found that when the number of household members decreased sharply compared to the basic model, up to 7.99 km² of additional residential land were required. In the second policy experiment, if the apartment floor area ratio was raised from 200% to 300%, it was possible to meet the demand for residential land with the current supply area of Seongnam-city. In the third policy experiment, it was found that even if the average number of floors in the commercial area was raised from four to five and the building-to-land ratio in the commercial area was raised from 80% to 85%, the demand for commercial land exceeded the supply area of the commercial area in Seongnam-city. This study is meaningful in that it proposes a new analytical model for land use demand prediction using system dynamics, and empirically analyzes the model by applying the actual urban planning status and statistics of Seongnam-city.

• Journal of the Economic Geographical Society of Korea
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• v.12 no.2
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• pp.123-141
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• 2009

Interregional migration is viewed as the most important component in regional population change in Korea. The purpose of this study is to analyze the structure of interrelationship among influential factors of interregional migration from the macro-viewpoint. During the period of 2000-05 the correlation between immigration and outmigration among 223 shi gun gu spatial unit was over 0.95, indicating that regions with high outmigration received high immigration. In this study the hypothesized cause-and-effect relationship among six influential factors of total migration flow was analyzed using path analysis. Based on the direct effect culturalwelfare environment has the biggest impact on immigration, while education environment and new housing environment are somewhat less and industrial-job opportunity environment the smallest impact. However based on the indirect effect, fiscal environment has the biggest impact on immigration, while industrial-job opportunity environment and infrastructure environment are somewhat less and new housing environment the smallest impact. If we consider the total effect, fiscal environment and cultural-welfare environment have the most significantly influenced on immigration. In particular, the influence of fiscal environment was remarkable in migration process through nonrecursive path and feedback loop.