• The Korean Journal of Pharmacology
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• v.32 no.1
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• pp.39-49
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• 1996

In the present study, we observed change in intracellular $Ca^{2+}$$([Ca^{2+}]_i)$ as measured with the fluorescent $Ca^{2+}-indicator$ fura-2 in association with force development of the rat basilar arteries during activation by$K^+$ depolarizing solution and U46619, a thromboxane analogue, in the absence and the presence of calcitonin-gent related peptide (CGRP). CGRP (30 and 100 nM) caused a concentration-dependent inhibition of U46619-induced contraction with decrease in $[Ca^{2+}]_i$, whereas it did not exert any effect on the $K^+$ (90 mM)-induced contraction and increase in $[Ca^{2+}]_i$, Further, $[Ca^{2+}]_i-force$ relationships were determined by plotting the ratio of $F_{340}/F_{380}$ $([Ca^{2+}]_i)$ as a function of the force induced by U46619, and the results were compared with those obtained in the presence of CGRP. The curves obtained in the presence of CGRP (30 and 100 nM) were significantly moved to downward without right shift of the curves suggesting that CGRP inhibited the U46619-induced contraction only by mediation of reduction in $[Ca^{2+}]_i$ with out any change in the sensitivity of contractile apparatus to $Ca^{2+}$. The CGRP-induced attenuation of $[Ca^{2+}]_i$ and force development was significantly inhibited under pretreatment with CGRP $(8{\sim}37)$ fragment (100 nM), a CGRP1 receptor antagonist. Both the reduced contraction and reduction in $[Ca^{2+}]_i$ caused by CGRP were fully reversed by pretreatment with charybdotoxin (100 nM) and iberiotoxin (100 nM), large conductance $Ca^{2+}-activated$ $K^+$ channel blockers, but not by apamin (300 nM), a small conductance $Ca^{2+}-activated$ $K^+$ channel blocker, and glibenclamide ( 1 ${\mu}M$), an ATP-sensitive $K^+$ channel blocker. In conclusion, it is suggested that the CGRP1 receptor, upon activation by CGRP, are coupled to opening of $Ca^{2+}-activated$ $K^+$ channel and cause to decrease in $[Ca^{2+}]_i$, thereby leading to vasodilation of the rat basilar artery. However, it is not defined that the mechanism underlying vasodilation whether the $K^+$ channel blockers, charybdotoxin and iberiotoxin directly block the CGRP receptors and that CGRP-evoked relaxation is dependent on the cyclic AMP or $K^+$ channel opening or both actions.

• The Korean Journal of Ceramics
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• v.4 no.2
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• pp.95-98
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• 1998

We have developed new type of superconducting-superionic conducting nanohybrids, $Ag_xI_wBi_2Sr_2Ca_{n-1}Cu_nO_y$ (n=1 and 2) by applying the chimie douce reaction to the superconducting Bi-based cuprates. These nanohybrids can be achieved by the stepwise intercalation whereby the $Ag^+$ ion is thermally diffused into the pre-intercalated iodine sublattice of $IBi_2Sr_2Ca_{n-1}Cu_nO_y$. According to the X-ray diffraction analysis, the Ag-I intercalates are found to have an unique heterostructure in which the superionic conducting Ag-I layer and the superconducting $IBi_2Sr_2Ca_{n-1}Cu_nO_y$ layer are regularly interstratified with a remarkable basal increment of ~7.3$\AA$. The systematic XAS studies demonstrate that the intercalation of Ag-I accompanies the charge transfer between host and guest, giving rise to a change in hole concentration of $CuO_2$ layer and to a slight $T_c$ change. The Ag K-edge EXAFS result reveals that the intercalated Ag-I has a $\beta$-AgI-like local structure with distorted tetrahedral symmetry, suggesting a mobile environment for the intercalated $Ag^+$ ion. In fact, from ac impedance analyses, we have found that the Ag-I intercalates possess a fast ionic conductivity ($\sigma_i=10^{-1.4}\sim 10^{-2.6}\Omega^{-1}\textrm{cm}^{-1}\;at\;270^{\circ}C$ with an uniform activation energy ($\DeltaE_a=0.22\pm 0.02$ eV). More interesting finding is that these intercalates exhibit high electronic conducting as well as ionic ones ($t_i$=0.02~0.60) due to their interstratified structure consisting of superionic conducting and superconducting layers. In this respect, these new intercalates are expected to be useful as an electrode material in various electrochemical devices.

• Proceedings of the Korean Vacuum Society Conference
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• 2011.02a
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• pp.204-205
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• 2011

In thin film silicon solar cells, p-i-n structure is adopted instead of p/n junction structure as in wafer-based Si solar cells. PECVD is a most widely used thin film deposition process for a-Si:H or ${\mu}c$-Si:H solar cells. For best performance of thin film silicon solar cell, the dopant profiles at p/i and i/n interfaces need to be as sharp as possible. The sharpness of dopant profiles can easily achieved when using multi-chamber PECVD equipment, in which each layer is deposited in separate chamber. However, in a single-chamber PECVD system, doped and intrinsic layers are deposited in one plasma chamber, which inevitably impedes sharp dopant profiles at the interfaces due to the contamination from previous deposition process. The cross-contamination between layers is a serious drawback of a single-chamber PECVD system in spite of the advantage of lower initial investment cost for the equipment. In order to resolve the cross-contamination problem in single-chamber PECVD systems, flushing method of the chamber with NH3 gas or water vapor after doped layer deposition process has been used. In this study, a new plasma process to solve the cross-contamination problem in a single-chamber PECVD system was suggested. A single-chamber VHF-PECVD system was used for superstrate type p-i-n a-Si:H solar cell manufacturing on Asahi-type U FTO glass. A 80 MHz and 20 watts of pulsed RF power was applied to the parallel plate RF cathode at the frequency of 10 kHz and 80% duty ratio. A mixture gas of Ar, H2 and SiH4 was used for i-layer deposition and the deposition pressure was 0.4 Torr. For p and n layer deposition, B2H6 and PH3 was used as doping gas, respectively. The deposition temperature was $250^{\circ}C$ and the total p-i-n layer thickness was about $3500{\AA}$. In order to remove the deposited B inside of the vacuum chamber during p-layer deposition, a high pulsed RF power of about 80 W was applied right after p-layer deposition without SiH4 gas, which is followed by i-layer and n-layer deposition. Finally, Ag was deposited as top electrode. The best initial solar cell efficiency of 9.5 % for test cell area of 0.2 $cm^2$ could be achieved by applying the in-situ plasma cleaning method. The dependence on RF power and treatment time was investigated along with the SIMS analysis of the p-i interface for boron profiles.

• Journal of the Korean Statistical Society
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• v.7 no.1
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• pp.3-10
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• 1978

Let $X_i,...,X_n$ be a random sample from a distribution with cumulants $K_1, K_2,...$. The statistic $t = \frac{\sqrt{x}(\bar{X}-K_1)}{S}$ has the well-known 'student' distribution with $\nu = n-1$ degrees of freedom if the $X_i$ are normally distributed (i.e., $K_i = 0$ for $i \geq 3$). An Edgeworth series expansion for the distribution of t when the $X_i$ are not normally distributed is obtained. The form of this expansion is Prob $(t

• Journal of the Korea Institute of Information Security & Cryptology
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• v.19 no.2
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• pp.49-61
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• 2009

Finite Field multiplication operation is one of the most important operations in the finite field arithmetic. Recently, Fan and Dai introduced a Shifted Polynomial Basis(SPB) and construct a non-pipeline bit-parallel multiplier for $F_{2^n}$. In this paper, we propose a new bit-parallel shifted polynomial basis type I and type II multipliers for $F_{2^n}$ defined by an irreducible trinomial $x^{n}+x^{k}+1$. The proposed type I multiplier has more efficient the space and time complexity than the previous ones. And, proposed type II multiplier have a smaller space complexity than all previously SPB multiplier(include our type I multiplier). However, the time complexity of proposed type II is increased by 1 XOR time-delay in the worst case.

• Transactions on Electrical and Electronic Materials
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• v.18 no.2
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• pp.70-73
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• 2017

We investigated n-i-p type single junction hydrogenated amorphous silicon oxide solar cells. These cells were without front surface texture or back reflector. Maximum power point efficiency of these cells showed that an optimized device structure is needed to get the best device output. This depends on the thickness and defect density ($N_d$) of the active layer. A typical 10% photovoltaic device conversion efficiency was obtained with a $N_d=8.86{\times}10^{15}cm^{-3}$ defect density and 630 nm active layer thickness. Our investigation suggests a correlation between defect density and active layer thickness to device efficiency. We found that amorphous silicon solar cell efficiency can be improved to well above 10%.

• Journal of Microbiology and Biotechnology
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• v.7 no.6
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• pp.373-377
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• 1997

The gene for isopenicillin N synthase (cyclase; IPNS) was cloned from Lysobacter lactamgenus using DNA probe amplified with primers based on the consensus sequences of isopenicillin N synthase genes of other ${\beta}$-lactam-producing microorganisms. The genomic library of L. lactamgenus using pUC18 plasmid cloned at the SacI site were screened with the PCR-generated DNA probe and three positive clones were isolated. Enzyme activities in E. coli clones were confirmed by bioassay and HPLC assay. Throughout the functional mapping, it was observed that the gene for isopenicillin N synthase is located at the 1.3-kb XhoI-BamHI fragment of insert of positive clones. Nucleotide sequencing at both ends of the XhoI-BamHI fragment revealed that IPNS of L. lactamgenus has the common amino acid sequences at amino- and carboxy-termini.

• Bulletin of the Korean Mathematical Society
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• v.57 no.2
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• pp.275-280
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• 2020

Let (R, m) be a Noetherian local Cohen-Macaulay ring and I be a proper ideal of R. Assume that β_R(I, R) denotes the constant value of depth_R(R/Iⁿ) for n ≫ 0. In this paper we introduce the new notion γ_R(I, R) and then we prove the following inequalities: β_R(I, R) ≤ γ_R(I, R) ≤ dim R - cd(I, R) ≤ dim R/I. Also, some applications of these inequalities will be included.

• Applied Chemistry for Engineering
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• v.20 no.6
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• pp.603-611
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• 2009

Thermotropic liquid crystalline behavior of a homologous series of penta-O-4-{4'-(cyanophenylazo)phenoxy}alkyl-D-glucopyranoses(CAGETn, n = 2~10, the number of methylene units in the spacer) has been investigated. The CAGETn with n of 2 and 7 exhibited enantiotropic nematic phases whereas other derivatives showed monotropic nematic phases. This is the first report of glucose derivatives that form thermotropic nematic phases. The isotropic-nematic transition temperatures ($T_{iNS}$) of CAGETns and their entropy variation at $T_{iN}$ showed the odd-even effect as a function of n. This behavior was rationalized in terms of the change in the average shape of the side chains as the parity of the spacer is varied. This rationalization also accounts for the observed variation of nematic-crystalline phase transition temperatures ($T_{NkS}$) and associoated entropy change at $T_{Nk}$. The entropy change at $T_{iN}$ or $T_{Nk}$ reaches a mininum at n = 3, before it increases again for n = 4. This may be attributed to the difference in the arrangement of the side groups. The mesophase properties of CAGETns were entirely different from those reported for partially or fully alkylated glucopyranoses. This result suggests that the degree of substitution and chemical structure of the substituents play an important role in the formation of the mesophase structures in the liquid crystals.

• Journal of Life Science
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• v.18 no.6
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• pp.782-788
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• 2008

The aim of this work is to show differences in the pattern of glycoconjugate composition in the intestines of four teleostean species (Sebastes schlegeli, Halichoeres poecilopterus, Bryzoichthys lysimus, and Takifugu pardalis). We compared four regions of all species studied. The specimens were processed and stained with nine kinds of biotinylated lectins (DBA, SBA, PNA, BSL- I , RCA- I , sWGA, UEA- I , LCA and Con A). Except for Sebastes schlegeli, no differences between regions were observed. The intestinal epithelium of Halichoeres poecilopterus possessed D-glucose/mannose residues in all regions. ${\beta}$-N-acetyl-D-galactosamine was distinctive along the intestines, although the pattern of diversity was different in Sebastes schlegeli, Bryzoichthys lysimus, and Takifugu pardalis. Additionally, the occurrence of Galactose-${\beta}$-1,3-N-acetyl-D-galactosamine and ${\alpha}$-D-galactose were confirmed in the proximal, middle, and distal intestine of Sebastes schlegeli, while rectal intestine lacked these sugar residues. Along with ${\beta}$-N-acetyl-D-galactosamine, ${\beta}$-N-acetyl-D-glucosamine and D-glucose/mannose were also determined in Bryzoichthys lysimus. Galactose-${\beta}$-1,3-N-acetyl-D-galactosamine, D-galactose, and D-glucose/mannose were also present in Takifugu pardalis.