• The Korean Journal of Pharmacology
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• v.23 no.2
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• pp.101-111
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• 1987

We investigated the binding properties of $(^3H)$ QNB and $(^3H)$ NMS to mAchR to elucidate the characterstics of mAchR in rat brain by using two different preparations (homogemates & intact brain cell aggregates). The binding properties of both ligands demonstrated high affinity and saturability in both experiments, however $(^3H)$ QNB showed a significantly higher maximal binding capacity than tha ot $(^3H)$ NMS 1. In rat brain homogenates; Displacement of both lignands with several mAchR antagonists resulted in competition curves in accoradnce with the law of massaction for QNB, atropine & scopolamine in thie preparation, also a similar profile was found for the quaternary ammonium analogs of atropine & scopolamine (methyl atropine & methylscopolamine) when $(^3H)$ NMS was used to label the receptors in rat brain. But when these hydrophillic antagonists were used to displace $(^3H)$ QNB, they showed interaction with high- and low-affinity binding sites in brain homogenates. Pirenzepine, the nonclassical mAchR antagonist, was able to displace both ligands from binding sites in this preparation. 2. In intact rat brain cell aggregates; Intact bain cell aggregates were used to elucidate the binding characteristics of $(^3H)$ NMS to mAchR in rat. The magnitude of binding of this ligand was related linearly to the amount of cell protein in the binding assay with a high ratio of total to nonspecific binding. mAchR antagonists displaced specific $(^3H)$ NMS binding according to the law of mass-action, while it was possible to resolve displacement curves using mAchR agonist into high-& low-affinity component. 3. Our results indicate that more hydrophilic receptor ligand $(^3H)$ QNB, displacement experiments in both tissues demonstrated that the lipid solubility of a particulr mAchR ligand might play an important role in determining its profile of binding to the mAchR, and the concentrations of mAchR in rat brain are both on the cell surface (membrane-bound receptor) and in the intracelluar membrane (intermembrane-bound receptor). 4. The results are discussed in terms of the usefulness of dissociated intact rat brain cells in studying mAchR in central nervous system.

• Journal of the Korean Society for Marine Environment & Energy
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• v.17 no.2
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• pp.63-69
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• 2014

Analysis frequency spectrum through observed wave data in northeastern shore, jeju island, during winter and fall, and review wave characteristics. In order to compute maximum wave height, we calculate the ratio of significant wave height to maximum wave height using the linear regression equation. In addition, for calculating JONSWAP spectrum, we assumed ${\gamma}$ value using significant wave height and peak frequency in the observation area. Consequently, the highest frequency is below 1 m in the case of significant wave height and during the first observation, the mean of height was estimated at 0.523 m and during the scend observation, it was 0.423 m. Furthermore, in peak frequency, the highest frequency was 0.12 Hz~0.15 Hz (period is nearly 6.67s~8.33s), the results of ${\gamma}$ from using significant wave height and peak frequency is 2.72 and the significant wave height calculated by straight linear regression equation was $1.635H_s$.

• Journal of the Korean Society of Radiology
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• v.9 no.4
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• pp.187-195
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• 2015

The active transport characteristics of anions of cell membrane model which irradiated by $^{60}Co\;{\gamma}-ray$ was investigated. The cell membrane model used in this experiment was a sulfonated copolymerized membrane of poly(1-methyl-4-vinylpyridiniumiodide-co-divinylbenzene : MeVP-DVBI). First, the initial flux of $OH^-$ and $Cl^-$, $Na^+$ of membrane which was not irradiated was decreased with increase of thickness of membrane $80-200{\mu}m$, increased with increase of NaOH concentration 0-0.5mol/L and MeVP-DVBI concentration 20-80% was increased with initial flux of $OH^-$ and $Cl^-$, decreased with initial flux of $Na^+$. Second, the initial flux of membrane which was irradiated was less than that. And the driving force of pH of irradiated membrane was significantly increased more than membrane which was not irradiated. The initial flux of the $OH^-$ ion was decreased with increase of $H^+$ ion concentration. As selective transport of $OH^-$ and $Cl^-$ of cell membrane model were abnormal, cell damages were appeared at cell.

• Korean Journal of Optics and Photonics
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• v.1 no.2
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• pp.210-216
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• 1990

This study was performed to obtain fundamental data on temperature increases in the dental tissues irradiated by IO.opm laser radiation. For this purpose a experimental facility was established. which was composed of a CO2 laser. a shutter unit and a temperature sensing device. The temperature changes in the pulp chamber of extracted molars. during and after the laser irradiation. were measured as function of laser power. the time of irradration and the thickness of the sample. An empirical formula for the maximum temperature increases, $\DeltaT_m$ was derived from the measured data as follows; $\DeltaT_m=\alphaP\Delta\tauexp(-\betad)$$ where P. $\Delta\tau$ and d are the laser power(W). irradiation time{sec) and the thickness(mm) between pulp chamber and occlusal surface. respectively. Also a theoretical calculation model based on simplified assumptions were established and the results from the calculation were compared with the measured temperature data. A fairly good agreement was obtained.obtained.

• Journal of The Korean Astronomical Society
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• v.38 no.2
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• pp.191-195
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• 2005

We used Subaru observations of A1689 (z = 0.183) to derive an accurate, model-independent mass profile for the entire cluster, r$\le$2Mpc/h, by combining magnification bias and distortion measurements. The projected mass profile steepens quickly with increasing radius, falling away to zero at r${\~}$1.0Mpc/h, well short of the anticipated virial radius. Our profile accurately matches onto the inner profile, r $\le$200kpc/ h, derived from deep HST / ACS images. The combined ACS and Subaru information is well fitted by an NFW profile with virial mass, $(1.93 \pm 0.20) {\times}10^{15} M_{\bigodot}$, and surprisingly high concentration, $C_{vir} = 13.7^{+1.4}_{-1.1}$, significantly larger than theoretically expected ($C_{vir} {\le}4$), corresponding to a relatively steep overall profile. These results are based on a reliable sample of background galaxies selected to be redder than the cluster E/SO sequence. By including the faint blue galaxy population a much smaller distortion signal is found, demonstrating that blue cluster members significantly dilute the true signal for r $\le$ 400kpc/ h. This contamination is likely to affect most weak lensing results to date.

• Journal of the Korean Society of Food Science and Nutrition
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• v.30 no.3
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• pp.500-504
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• 2001

Gamma irradiation was applied to reduce egg allergy. Ovalbumin (OVA), an egg white protein, was used as model allergen and was gamma-irradiated at 3, 5, or 10 kGy in an aqueous state (2.0 mg/mL). The changes in allergenic and antigenic properties of OVA resulted from gamma irradiation were monitored by ELISA with serum from egg-hypersensitive patients (H-IgE), and mouse monoclonal IgG (M-IgG) or rabbit polyclonal IgG (R-IgG). The binding ability of H-IgE to irradiated OVA was dose-dependently reduced. However, IgGs from animal did better recognize 3 or 5 kGy-irradiated OVA. In the evaluation of immune reactivity using blind test, the reactivity of H-IgE rapidly decreased depending upon the irradiation dose. However, the reactivities of M-IgG and R-IgG was higher at 5 and 3 kGy-irradiated OVA than non-irradiated control. The results provide a new possibility to use irradiation process for reducing the allergenicity of egg white.

• Journal of Ecology and Environment
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• v.38 no.4
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• pp.493-503
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• 2015

This study analyzed how spatial distribution of Himantormia lugubris is affected by the microenvironment in the Antarctic Specially Protected Area (ASPA) No. 171 located in the Barton Peninsula of King George Island that belongs to the maritime Antarctic. In order to determine the population structure of H. lugubris growing in Baekje Hill within ASPA No. 171, we counted the individuals of different size groups after dividing the population into 5 growth stages according to mean diameter as follows: ≤ 1 cm, 1-3 cm, 3-5 cm, 5-10 cm, and ≥ 10 cm. The count of H. lugubris individuals in each growth stage was converted into its percentage with respect to the entire population, which yielded the finding that stages 1 through 5 accounted for 32.8%, 25.3%, 15.9%, 22.5%, and 3.5%, respectively. This suggests that the population of H. lugubris in ASPA No. 171 has a stable reverse J-shaped population structure, with the younger individuals outnumbering mature ones. The mean density of H. lugubris was 17.6/0.25 m², mean canopy cover 13.3%, and the mean dry weight 37.8 g/0.25 m². It began to produce spore in the sizes over 3 cm, and most individuals measuring 5-10 cm were adults with sexually mature apothecia. The spatial distribution of H. lugubris was highly heterogeneous. The major factors influencing its distribution and performance were found to be the period covered by snow, wind direction, moisture, size of the substrate, and canopy cover of Usnea spp. Based on these factors, we constructed a prediction model for estimating the spatial distribution of H. lugubris. Conclusively, the major factors for the spatial distribution of H. lugubris were snow, wind, substrate and the competition with Usnea spp. These results are important for understanding of the distribution in the maritime Antarctic and evolution of H. lugubris that claims a unique life history and ecological niche.

• The KIPS Transactions:PartA
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• v.9A no.4
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• pp.519-524
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• 2002

In this paper we study the qualify of sequential coverage analysis under a scenario of distributed stochastic simulation known as MRIP(Multiple Replications In Parallel) in terms of the confidence intervals of coverage and the speedup. The estimator based in the F-distribution was applied to the sequential coverage analysis of steady-state means. in simulations of the $M/M/1/{\infty},\;M/D/I/{\infty}\;and\;M/H_{2}/1/{\infty}$ queueing systems on a single processor and multiple processors. By using multiple processors under the MRIP scenario, the time for collecting many replications needed in sequential coverage analysis is reduced. One can also easily collect more replications by executing it in distributed computers or clusters linked by a local area network.

• Proceedings of the International Microelectronics And Packaging Society Conference
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• 2002.11a
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• pp.73-77
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• 2002

Characteristics of Cu/Si/Cu ohmic contacts to n-type 4H-SiC were investigated systematically. The ohmic contacts were formed by rf sputtering of multi layer Cu/Si/Cu sputtered sequentially. The annealings were peformed With 2-Step using RTP in vacuum ambient. The specific contact resistivity($\rho$c), sheet resistance(Rs), contact resistance(Rc), transfer length(L$_{T}$) were calculated from resistance(R$_{T}$) versus contact spacing(d) measurements obtained from TLM(transmission line method) structure. Best results were obtained for a sample annealed at vacuum as $\rho$c = 1.0x10$^{-6}$ $\Omega$$\textrm{cm}^2$, Rc = 2$\Omega$ and L$_{T}$ = 1${\mu}{\textrm}{m}$. The physical properties of contacts were examined using XRO and AES. The results showed that copper silicide was formed on SiC and Cu was migrated into SiC.o SiC.

• Journal of Life Science
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• v.21 no.9
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• pp.1214-1218
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• 2011

We investigated the fruits of Rubus crataegifolius Bge, a plant which has been traditionally used in Korea in phytotherapy, to describe antioxidant materials from plant sources. R. crataegifolius fruits were extracted with methanol and further fractionated into n-hexane, diethyl ether, and ethyl acetate. The antioxidant activity of each fraction and the residue was assessed using a 1,1-diphenyl-2-picrylhydrazyl (DPPH), $H_2O_2$ radical scavenging method, and their cytotoxicity on human primary kerationcyte (HK) was determined by an MTS assay. The R. crataegifolius fruit methanol extract showed strong antioxidant activity (75.04%, 50%) compared with vitamin C (79.9%, 54.1%) by the DPPH, and $H_2O_2$ method, respectively. The measured activity from the subsequent extracts of the methanol extract were 20.3% for n-hexane fraction (HF), 68.8% for diethyl ether fraction (DF), 67.1% for ethyl acetate fraction (EF), and 67.1% for the residue fraction (RE) by DPPH and 2.2% for HF, 1.6% for DF, 10% for EF, and 50% for the RE by $H_2O_2$ assay. An oxidative stress model of HK was established under a suitable concentration (1 mM). The cell viability of the RE treated group increased and the percentage of apoptotic cells decreased at concentrations of 0.005-0.02% RE compared with the $H_2O_2$ treated group. Fruit extracts of the medicinal plant R. crataegifolius showed potent antioxidant activity and the ability to relieve cell damage from $H_2O_2$ induced injury to HK.