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The Kinetics of Hyperpolarization Activated Current$(i_f)$ in Sinoatrial Node of the Rabbit (토끼 동방결결에서 Pacemaker전류(과분극에 의해 활성화되는 내향전류, $i_f$)의 동력학적 특성에 관한 연구)

  • Earm, Yung-E
    • The Korean Journal of Physiology
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    • v.17 no.1
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    • pp.1-11
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    • 1983
  • 1) The two microelectrode method was used to voltage clamp small preparations of rabbit sinoatrial node. The kinetics of hyperpolarization activated inward current, $i_f$ were analysed. 2) The hrperpolarization pulses activated $i_f$ current in the presence of $10^{-7}g/ml$ TTX and 2 mM $Mn^{2+}$. The activation range was in between -45 mV to -75 mV. The current magnitude was increased and time course was faster by strong hyperpolarization pulses. 3) Standard envelope tests indicated that this current is exponentially controlled by single gate. 4) Semilogarithmic plot of $i_f$ activation versus time was found to be linear in the activation range. The decrease in current magnitude and the shifts in activation curve and rate constants curve to the hyperpolarizing direction were obtained with $Ba^{2+}$, indicating that $Ba^{2+}$ shifts the voltage dependence of the gating kinetics, were partially reversed by 24 mM $K^+$.

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Action Mechanisms of NANC Neurotransmitters in Smooth Muscle of Guinea Pig Ileum (기니픽의 회장평활근에서 NANC 신경전달물질의 작용기전)

  • Kim, Jong-Hoon;Kang, Bok-Soon;Lee, Young-Ho
    • The Korean Journal of Physiology and Pharmacology
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    • v.1 no.6
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    • pp.783-796
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    • 1997
  • The relaxation induced by stimulation of the inhibitory non-adrenergic, non-cholinergic (iNANC) nerve is mediated by the release of iNANC neurotransmitters such as nitric oxide (NO), vasoactive intestinal peptide (VIP) and adenosine triphosphate (ATP). The mechanisms of NO, VIP or ATP-induced relaxation have been partly determined in previous studies, but the detailed mechanism remains unknown. We tried to identify the nature of iNANC neurotransmitters in the smooth muscle of guinea pig ileum and to determine the mechanism of the inhibitory effect of nitric oxide. We measured the effect of NO-donors VIP and ATP on the intracellular $Ca^{2+}$ concentration$([Ca^{2+}]_i)$, by means of a fluorescence dye(fura 2) and tension simultaneously in the isolated guinea pig ileal smooth muscle. Following are the results obtained. 1. Sodium nitroprusside $(SNP:10^{-5}\;M)$ or S -nitro-N-acetyl-penicillamine $(SNP:10^{-5}\;M)$ decreased resting $[Ca^{2+}]_i$ I and tension of muscle. SNP or SNAP also inhibited rhythmic oscillation of $[Ca^{2+}]_i$ and tension. In 40mM $K^+$ solution or carbachol ($(CCh:10^{-6}\;M)$-induced precontracted muscle, SNP decreased muscle tension. VIP did not change $[Ca^{2+}]_i$ and tension in the resting or precontracted muscle, but ATP increased resting $[Ca^{2+}]_i$ and tension in the resting muscle. 2. 1H-[1,2,4]oxadiazol(4,3-a)quinoxalin-1-one $(ODQ:1\;{\mu}M)$, a specific inhibitor of soluble guanylate cyclase, limited the inhibitory effect of SNP 3. Glibenclamide $(10\;{\mu}M)$, a blocker of $K_{ATP}$ channel, and 4-aminopyridine (4-AP:5 mM), a blocker of delayed rectifier K channel, apamin $(0.1\;{\mu}M)$, a blocker of small conductance $K_{Ca}$ channel had no effect on the inhibitory effect of SNP. Iberiotoxin $(0.1\;{\mu}M)$, a blocker of large conductance $K_{Ca}$ channel, significantly increased the resting $[Ca^{2+}]_i$, and tension, and limited the inhibitory effect of SNP. 4. Nifedipine $(1\;{\mu}M)$ or elimination of external $Ca^{2+}$ decreased not only resting $[Ca^{2+}]_i$ and tension but also oscillation of $[Ca^{2+}]_i$ and tension. Ryanodine $(5\;{\mu}M)$ and cyclopiazonic acid $(10\;{\mu}M)$ decreased oscillation of $[Ca^{2+}]_i$ and tension. 5. SNP decreased $Ca^{2+}$ sensitivity of contractile protein. In conclusion, these results suggest that 1) NO is an inhibitory neurotransmitter in the guinea pig ileum, 2) the inhibitory effect of SNP on the $[Ca^{2+}]_i$ and tension of the muscle is due to a decrease in $[Ca^{2+}]_i$ by activation of the large conductance $K_{Ca}$ channel and a decrease in the sensitivity of contractile elements to $Ca^{2+}$ through activation of G-kinase.

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A Study on Printed Books of $M\grave{e}ngz\check{i}$ in Choseon Dynasty (조선시대에 간행된 <맹자(孟子)>의 제판본(諸板本)에 관한 연구(硏究))

  • Ahn, Hyeon-Ju
    • Journal of Korean Library and Information Science Society
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    • v.37 no.1
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    • pp.305-328
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    • 2006
  • This paper is a bibliographic analysis on printed books of $M\grave{e}ngz\check{i}$(孟子) in Choseon Dynasty. Through examination of the physical characteristics of books in many institutes and private collections, $M\grave{e}ngz\check{i}j\acute{i}zh\grave{u}d\grave{a}q\acute{a}n$(孟子集註大全)was systematically explored, which was the most frequently published $M\grave{e}ngz\check{i}$(孟子) in Choseon Dynasty. $M\grave{e}ngz\check{i}$(孟子) was published mainly in Kyungki and Kyungsang provinces, and in the period of 17C to 19C. There are two streams of $M\grave{e}ngz\check{i}j\acute{i}zh\grave{u}d\grave{a}q\acute{a}n$. One is the series of the reprinted edition of $M\acute{i}ngbon$(明本覆刻), originated from Saseookyungdaejun(四書五經大全), compiled by Hokwang(湖廣) and colleagues in $M\acute{i}ng$(明). The second is the series of Chungyuja books(丁酉字本) among movable type books of Choseon(朝鮮活字本), the contents of which being the same as the other stream. Also, $M\grave{e}ngz\check{i}d\grave{a}iw\acute{e}n$(孟予大文) and $M\grave{e}ngz\check{i}zh\grave{e}ngw\acute{e}n$(孟子正文) are frequently published.

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COMINIMAXNESS OF LOCAL COHOMOLOGY MODULES WITH RESPECT TO IDEALS OF DIMENSION ONE

  • Roshan-Shekalgourabi, Hajar
    • Honam Mathematical Journal
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    • v.40 no.2
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    • pp.211-218
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    • 2018
  • Let R be a commutative Noetherian ring, a be an ideal of R and M be an R-module. It is shown that if $Ext^i_R(R/a,M)$ is minimax for all $i{\leq}{\dim}\;M$, then the R-module $Ext^i_R(N,M)$ is minimax for all $i{\geq}0$ and for any finitely generated R-module N with $Supp_R(N){\subseteq}V(a)$ and dim $N{\leq}1$. As a consequence of this result we obtain that for any a-torsion R-module M that $Ext^i_R(R/a,M)$ is minimax for all $i{\leq}dim$ M, all Bass numbers and all Betti numbers of M are finite. This generalizes [8, Corollary 2.7]. Also, some equivalent conditions for the cominimaxness of local cohomology modules with respect to ideals of dimension at most one are given.

On Direct Sums of Lifting Modules and Internal Exchange Property

  • Dejun, Wu
    • Kyungpook Mathematical Journal
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    • v.46 no.1
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    • pp.11-18
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    • 2006
  • Let R be a ring with identity and let $M=M_1{\bigoplus}M_2$ be an amply supplemented R-module. Then it is proved that $M_i$ has ($D_1$) and is $M_j-^*ojective$ for $i{\neq}j$, i = 1, 2, if and only if for any coclosed submodule X of M, there exist $M\acute{_1}{\leq}M_1$ and $M\acute{_2}{\leq}M_2$ such that $M=X{\bigoplus}M\acute{_1}{\bigoplus}M\acute{_2}$.

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PCR-RFLP patterns of three kinds of Metagonimus in Korea (국내에 존재하는 세 종류 메타고니무스속 흡충의 RCR-RFLP반응양상)

  • 유재란;정진성
    • Parasites, Hosts and Diseases
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    • v.35 no.4
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    • pp.271-276
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    • 1997
  • We tried to compare the three kinds oi Metagonimur species. M. Wokognulci, Ifetafonimus Miyata type, and M. tnknhashii, which were Know to be distributed in Korea with polymerase chain reaction based-restriction fragment length polymorphism (PCR- RFLP) patterns. We amplified the internal transcribed spacer 1 (ITSI) site of ribosomal RNA and mitochondrial cytochrome c oxidase I (mCOI) gene. The restriction patterns of ITSI gene loth Rsc I, ALu I and Msp I showed multiple fragmented bands of different sizes between three kinds of Metcgonimus. In case of mc01 gene, Rsc I and Alu I enzymes produced differentially fragmented band patterns. According to the parsimony analysis of PCR-RFLP patterns, the estimated genetic divergence between M Wokognwai and Metasoninus Miyata type was 0.034880, between Metusoninus Miyata type and M. tckc- hushii was 0.028098, between M. wokogawai and M. tnkahashii was 0.018179. It is suggested that Metasonimus Miyata type may be separate species and evolutionize at the older time than the other two species.

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TENSOR PRODUCTS OF C*-ALGEBRAS WITH FIBRES GENERALIZED NONCOMMUTATIVE TORI AND CUNTZ ALGEBRAS

  • Boo, Deok-Hoon;Park, Chun-Gil
    • Journal of the Chungcheong Mathematical Society
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    • v.13 no.1
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    • pp.139-144
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    • 2000
  • The generalized noncommutative torus $T_{\rho}^d$ of rank m was defined in [2]. Assume that for the completely irrational noncommutative subtorus $A_{\rho}$ of rank m of $T_{\rho}^d$ there is no integer q > 1 such that $tr(K_0(A_{\rho}))=\frac{1}{q}{\cdot}tr(K_0(A_{\rho^{\prime}}))$ for $A_{\rho^{\prime}}$ a completely irrational noncommutative torus of rank m. All $C^*$-algebras ${\Gamma}({\eta})$ of sections of locally trivial $C^*$-algebra bundles ${\eta}$ over $M=\prod_{i=1}^{e}S^{2k_i}{\times}\prod_{i=1}^{s}S^{2n_i+1}$, $\prod_{i=1}^{s}\mathbb{PR}_{2n_i}$, or $\prod_{i=1}^{s}L_{k_i}(n_i)$ with fibres $T_{\rho}^d{\otimes}M_c(\mathbb{C})$ were constructed in [6, 7, 8]. We prove that ${\Gamma}({\eta}){\otimes}M_{p^{\infty}}$ is isomorphic to $C(M){\otimes}A_{\rho}{\otimes}M_{cd}(\mathbb{C}){\otimes}M_{p^{\infty}}$ if and only if the set of prime factors of cd is a subset of the set of prime factors of p, that $\mathcal{O}_{2u}{\otimes}{\Gamma}({\eta})$ is isomorphic to $\mathcal{O}_{2u}{\otimes}C(M){\otimes}A_{\rho}{\otimes}M_{cd}(\mathbb{C})$ if and only if cd and 2u - 1 are relatively prime, and that $\mathcal{O}_{\infty}{\otimes}{\Gamma}({\eta})$ is not isomorphic to $\mathcal{O}_{\infty}{\otimes}C(M){\otimes}A_{\rho}{\otimes}M_{cd}(\mathbb{C})$ if cd > 1 when no non-trivial matrix algebra can be ${\Gamma}({\eta})$.

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A syudy on electrochemical charcteristic of $Li_{1-x}Mn_{2}O_{4}$(0$\leq$x$\leq$0.075) ($Li_{1-x}Mn_{2}O_{4}$(0$\leq$x$\leq$0.075)의 전기화학적 특성연구)

  • 박종광;고건문;김민기;이남재;임석진;한병성
    • Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
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    • 2000.07a
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    • pp.444-447
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    • 2000
  • The spinel L $i_{1-x}$ M $n_2$ $O_4$has been synthesized by the solid-state reaction. L $i_{l-x}$M $n_2$ $O_4$which includes a mixture of LiOH . $H_2O$ and Mn $O_2$prepared by preliminary heating at 35$0^{\circ}C$ for 12hr. L $i_{l-x}$M $n_2$ $O_4$fired at temperature range from 75$0^{\circ}C$ for 48hr. The structure and the electrochemical characteristics of spinel to L $i_{1-x}$ M $n_2$ $O_4$which is fabricated by changing sintering condition from starting materials are investigated. The cyclic voltammetric measurement was performed using 3 electrode cells. Electrode specific capacity and cycle life behavior were tested in a 3.0~4.2V range at a constant current density of 0.45mA/c $m^2$. To improve the cycle performance of spinel L $i_{l-x}$M $n_2$ $O_4$as the cathode of 4V class lithium secondary batteries, spinel phases L $i_{1-x}$ M $n_2$ $O_4$were Prepared at various lithium. The results showed that discharge capacity of L $i_{l-x}$M $n_2$ $O_4$varied at lithium quantity decrease with increasing lithium add quantity. The discharge capacities of L $i_{0.925}$M $n_2$ $O_4$and LiM $n_2$ $O_4$revealed 108 and 117mAh/g, respectively.spectively.y.

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Success Factor of m-commerce; A case of DoCoMo′s i-Mode Service (기술언어가 m-commerce의 성공에 미치는 영향에 관한 소고 - i-mode 서비스를 중심으로 -)

  • 김광희
    • Proceedings of the Korea Inteligent Information System Society Conference
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    • 2001.06a
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    • pp.305-314
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    • 2001
  • 본 논문해서는 m-커머스의 대표적인 성공 사례로 꼽히고 있는 NTT DoCOMo의 i-mode 서비스에 초점을 맞추어 성공요인과 그러한 성공을 이끌어 내는데 결정적인 역할을 담당한 웹 페이지 기술언어에 대해 살펴보았다. 분석 결과에 근거하면, i-mode 서비스의 대대적인 성공은 끊임없이 Positive Feedback의 계기를 만들어 냄으로써 가능하게 되었는데, 그것은 다름 아닌 C-HTML이라는 웹페이지 기술언어의 채용이 많은 역할을 하고 있다.

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