• Journal of Photoscience
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• v.2 no.2
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• pp.63-67
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• 1995

Zinc plays a key role in genetic expression, cell division, and growth and is essential for the function of more than 200 enzymes; effects of zinc deficiency induce many syndromes, including abnormal visual adaptation. The pigment epithelium (EP) contains high concentrations of zinc in humans and in animals and it participates in threshold elevation, visual sensitivity increment, and acceleration of rhodopsin regeration during visual adaptation. The origin of c-wave of electroretinogram(ERG) is not only pigment epithelium as shown in present research, but also other cell layers, perhaps the photoreceptors. We propose zinc as a candidate for an internal messenger which participates in signal amplification.

• Journal of The Korean Astronomical Society
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• v.29 no.spc1
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• pp.299-301
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• 1996

It. has been discovered that. active regions commonly have numerous flare-like transient. loop brightenings. We use a magnetic reconnection theory driven by a ponderamotive force on account. of the basic properties of a transient. brightening: lifetime a few mins, total energy $10^{25}\~10^{29}$ erg. The numerical results are consistent with the observations.

• Journal of The Korean Astronomical Society
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• v.29 no.spc1
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• pp.315-316
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• 1996

Based on X-ray (1-8 ${\AA}$) flux data for 1972-1995 the integral spectra of solar flare energy were computed. It has been shown that the spectral index $\beta$ of the integral energy spectrum (IES) vanes systematically with the 11-year cycle phase. The interval of $\beta$-variations (0.47 <$\beta$<1) is characteristic of UV-Cet stars. The maximum energy of the X-ray flares does not exceed $10^{32}$ erg.

• Proceedings of the KIEE Conference
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• 2000.07d
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• pp.3222-3226
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• 2000

In this study, the variations of human physiological signals(EEG and ERG) were measured on a various optic stimulation. From the analysis of the physiological signals, it was cleared that the optimum intensity of light exits at its sensing.

• Journal of the Korean Magnetics Society
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• v.9 no.4
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• pp.184-189
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• 1999

1000 $\AA$ thick Fe films were epitaxially grown on MgO(001) by an rf sputtering and effects of substrate temperature on the structural and magnetic properties were investigated. X-ray diffraction intensity increased with increasing substrate temperature and inter-planar spacing $d_{(002)}$ decrease with increasing the temperature up to 25$0^{\circ}C$. The increased intensity and decreased inter-planar spacing were thought to be attributed to the enhancement of lattice match between Fe films and MgO, thus yielding good epitaxial growth. By using torque magnetometer, VSM and pole figure, very nice epitaxial growth of sputtered Fe films on MgO could be confirmed and $K_1$ value of Fe films grown at 25$0^{\circ}C$ was $4.6{\times}10^5\;erg/cc$, which was very similar to that of bulk single Fe crystal.

• Journal of The Korean Astronomical Society
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• v.44 no.5
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• pp.161-175
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• 2011

We examine the dependence of the morphology of spiral galaxies on the environment using the KIAS Value Added Galaxy Catalog (VAGC) which is derived from the Sloan Digital Sky Survey (SDSS) DR7. Our goal is to understand whether the local environment or global conditions dominate in determining the morphology of spiral galaxies. For the analysis, we conduct a morphological classification of galaxies in 20 X-ray selected Abell clusters up to z~0.06, using SDSS color images and the X-ray data from the Northern ROSAT All-Sky (NORAS) catalog. We analyze the distribution of arm classes along the clustercentric radius as well as that of Hubble types. To segregate the effect of local environment from the global environment, we compare the morphological distribution of galaxies in two X-lay luminosity groups, the low-$L_x$ clusters ($L_x$ < $0.15{\times}10^{44}$erg/s) and high-$L_x$ clusters ($L_x$ > $1.8{\times}10^{44}$erg/s). We find that the morphology-clustercentric relation prevails in the cluster environment although there is a brake near the cluster virial radius. The grand design arms comprise about 40% of the cluster spiral galaxies with a weak morphology-clustercentric radius relation for the arm classes, in the sense that flocculent galaxies tend to increase outward, regardless of the X-ray luminosity. From the cumulative radial distribution of cluster galaxies, we found that the low-$L_x$ clusters are fully virialized while the high-$L_x$ clusters are not.

• Journal of the Korean Chemical Society
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• v.55 no.3
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• pp.392-399
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• 2011

Two conformations of benzoic acid derivatives ($NH_2$, OH, H, F, Cl, CN, NO, $NO_2$) have been investigated at MP2, DFT and HF level using the 6-311++G(d,p) basis set. It was found that the cis isomers are more stable. Hydrogen bonding formation of benzoic acids has been estimated from stabilization energies. The calculated hydrogen-bonding energies of dimers showed a cooperative interaction in the cyclic ones. It was found that an electron-releasing group (ERG) into the phenyl rings resulted in the formation of more stable hydrogen bonding. Red shift of O-H bond was found from -565.3 to -589.3 for dimers. The natural bond orbital (NBO) analysis was applied to characterize nature of the interaction.

• The Korean Journal of Physiology and Pharmacology
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• v.16 no.5
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• pp.327-332
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• 2012

Sertraline is a commonly used antidepressant of the selective serotonin reuptake inhibitors (SSRIs) class. In these experiments, we have used the whole cell patch clamp technique to examine the effects of sertraline on the major cardiac ion channels expressed in HEK293 cells and the native voltage-gated $Ca^{2+}$ channels in rat ventricular myocytes. According to the results, sertraline is a potent blocker of cardiac $K^+$ channels, such as hERG, $I_{Ks}$ and $I_{K1}$. The rank order of inhibitory potency was hERG > $I_{K1}$ > $I_{Ks}$ with $IC_{50}$ values of 0.7, 10.5, and 15.2 ${\mu}M$, respectively. In addition to $K^+$ channels, sertraline also inhibited $I_{Na}$ and $I_{Ca}$, and the $IC_{50}$ values are 6.1 and 2.6 ${\mu}M$, respectively. Modification of these ion channels by sertraline could induce changes of the cardiac action potential duration and QT interval, and might result in cardiac arrhythmia.

• Journal of Veterinary Clinics
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• v.34 no.5
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• pp.341-346
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• 2017

This study was performed to evaluate the effects of an intravitreal injection of cidofovir in beagle dogs. Nine beagle dogs (18 eyes) were used and randomly assigned to the following three groups of various dosages: 100, 500 and $1000{\mu}g$. Aqueous paracentesis was followed by an intravitreal injection of cidofovir. Intraocular pressure (IOP) was measured twice a week and electroretinography (ERG) and ophthalmoscopic examination were performed every week during the study. At the end of the study, all eyes were enucleated for histopathologic evaluation after euthanasia. The IOPs in the 500 and $1000{\mu}g$ groups were statistically lower than baseline with no significant IOP changes in the $100{\mu}g$ group. Reduced amplitudes of ERG recordings were identified in the eyes injected with higher dose groups than the $100{\mu}g$ group. Histopathologic examination revealed that there were dose-related toxicities to the ciliary body and the retina. These results suggest that intravitreal cidofovir had dose-dependent IOP lowering effects associated with ciliary body destruction, but had the potential to cause retinal toxicity in beagle dogs.

• The Bulletin of The Korean Astronomical Society
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• v.41 no.2
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• pp.67.3-68
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• 2016

An X1.6 flare occurred in AR 12192 on 2014 October 22 around 14:06 UT and was observed by Hinode, IRIS, SDO and RHESSI. We analyze a bright kernel which produces a white light flare (WLF) with continuum enhancement and a hard X-ray (HXR) peak. Taking advantage of the spectroscopic observations of IRIS and EIS, we measure the temporal variation of the plasma properties in the bright kernel in the chromosphere and corona. We found that explosive evaporation was observed when the WLF occurred, even though the intensity enhancement in hotter lines is quite weak. The temporal correlation of the WLF, HXR peak, and evaporation flows indicates that the WLF was produced by accelerated electrons. To understand the white light emission processes, we calculated the deposited energy flux from the non-thermal electrons observed by RHESSI and compared it to the dissipated energy estimated from the chromospheric lines (Mg II triplet) observed by IRIS. The deposited energy flux from the non-thermal electrons is about $3.1{\times}10^{10}erg\;cm^{-2}s^{-1}$ when we assume a cut-off energy of 20 keV. The estimated energy flux from the temperature changes in the chromosphere measured from the Mg II subordinate line is about $4.6-6.7{\times}10^9erg\;cm^{-2}s^{-1}$, 15 - 22 % of the deposited energy. By comparison of these estimated energy fluxes we conclude that the continuum enhancement was directly produced by the non-thermal electrons.