• Title/Summary/Keyword: M.I.V

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Phytosociological Studies on the Beech(Fagus multinervis Nakai) Forest and the Pine (Pinus parviflora S. et Z.) Forest of Ulreung Island, Korea (한국 울릉도의 너도밤나무(Fagus multinervis Nakai)림 및 섬잣나무(Pinus parviflora S. et Z.)림의 식물사회학적 연구)

  • 김성덕
    • Journal of Plant Biology
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    • v.29 no.1
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    • pp.53-65
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    • 1986
  • The montane forests of Ulreung Island, Korea, were investigated by the ZM school method. By comparing the montane forests of this island with those of Korean Peninsula and of Japan, a new order, F a g e t a l i a m u l t i n e r v i s, a new alliance, F a l g i o n m u l t i n e r v i s, a new association, H e p a t i c o-F a g e t u m m u l t i n e r v i s and Rhododendron brachycarpum-Pinus parviflora community were recognized. The H e p a t i c o - F a g e t u m m u l t i n e r v i s was further subdivided into four subassociations; Subass. of Sasa kurilensis, Subass. of Rumohra standishii, Subass. of Rhododendron brachycarpum and Subass. of typicum. Each community was described in terms of floristic, structural and environmental features.

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Study on Sensory Papillae of Metagonimus yokogawai Cercaria (Metagonimus yokogawai 세르카리아의 감각유두에 관한 연구)

  • 김재진;민득영소진탁
    • Parasites, Hosts and Diseases
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    • v.22 no.1
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    • pp.11-20
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    • 1984
  • A number of studies on the papillae of cercariae of trematodes reported that the papillar patterns (or chaetotaxy) of cercariae might be an excellent method to attain better understanding of the digenetic trematodes (Richard, 1971 ; Short and Cartrett, 1973; Bayssade-Dufour, 1979) . The present study was aimed to determine the number, distribution pattern and structure of the sensory papillae of Metagonimus yokogawai cercariae, and to elucidate the chaetotaxy of this digenetic trematode. M. yokogawai cercariae were pipetted from a vial in which infected snails (Semisulcospira libertina) had been kept for 3 hours. The snails were collected from an endemic area of M. yokogawai, Boseong river in west-southern part of Korea. Observations of papillae were based on light microscopy of those stained with silver nitrate, and on scanning electron microscopy The results are summarized as follows: 1, All papillae observed were uniciliated. 2. Cilia in anterior tip were shorter than the others in other portions. 3. The body papillae were arranged in essentially symmetrical patterns, Total number of the papillae was 126(63 pairs) in average; anterior tip 40(20 pairs), ventral 20(10 pairs), lateral 42(21 pairs), and caudal 8(4 pairs). 4. The chaetotany of M. yokogawai cercaria was: Ci cycle ($3+3C_{I}V,{\;}2+2C_{I}L,{\;}2+3C_{I}D),{\;}C_{II}{\;}cycle(2C_{II}V,{\;}1C_{II}L,{\;}2C_{II}D),{\;}C_{lll}{\;}cycle{\;}(1+lC_{III}V,{\;}1C_{IlI}L),{\;}C_{IV}{\;}cycle{\;}(1C_{IV}V,{\;}IC_{lV}L){\;}in{\;}cephalic{\;}region:{\;}A_I(1A_{IV}V,{\;}1+2A_{I}L,{\;}1A_{I}D),{\;}A_{II}(1A_{II}V,{\;}1+3A_{II}L,{\;}1A_{II}D),{\;}A_{III}(1A_{III}V,{\;}1+1A_{III}L,{\;}1A_{III}D){\;}and{\;}A_{IV}(1A_{IV}V,{\;}2A_{IV}L)$ in antacetabular region: $1M_{I}V{\;}and{\;}2M_{I}L$ in median: $1+1P_{I}L,{\;}1P_{II}L,{\;}1P_{II}D,{\;}1P_{III}L,{\;}1P_{IV}L{\;}and{\;}1P_{IV}D$ in postacetabular region: 2-2-2-2 in caudal region.

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Increase of Intracellular $Ca^{2+}$ Concentration by Vibrio Vulnificus Cytolysin in Rat Platelets; Triggering Mechanism of Platelet Cytolysis

  • Park, Jin-Bong;Chae, Soo-Wan
    • The Korean Journal of Physiology and Pharmacology
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    • v.3 no.2
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    • pp.199-205
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    • 1999
  • Vibrio vulnificus cytolysin caused platelet cytolysis and increased intracellular calcium concentration $([Ca^{2+}]_i)$ of rat platelets in a concentration-dependent manner. In the presence of V. vulnificus cytolysin (3 HU/ml), lactate dehydrogenase (LDH) activity was increased from $1.3{\pm}0.4%$ of control to $64.3{\pm}3.4%$ in platelet suspension buffer. In $Ca^{2+}-free$ platelet suspension buffer, however, V. vulnificus cytolysin did not induce $[Ca^{2+}]_i$ increase and LDH release. Addition of EGTA (2 mM) to suspension buffer after the initial $Ca^{2+}$ influx reversed $[Ca^{2+}]_i$ to the control level. However, a $Ca^{2+}$ channel blocker verapamil $(20\;{\mu}M)$ or mefenamic acid $(20\;{\mu}M)$ did not inhibit V. vulnificus cytolysin-induced $[Ca^{2+}]_i$ increase and LDH release. Divalent cations such as $Co^{2+},\;Cd^{2+}\;or\;Mn^{2+}$ (2 mM each) also did not alter V. vulnificus cytolysin-induced $[Ca^{2+}]_i$ increase and LDH release. V. vulnificus cytolysin (3 HU/ml)-induced calcium influx was completely blocked by lanthanum (2 mM). Lanthanum (2 mM) also completely blocked V. vulnificus cytolysin (3 HU/ml)-induced LDH release. Osmotic protectants such as, raffinose, sucrose or PEG600 (50 mM each) did not inhibit the lytic activity of V. vulnificus cytolysin. In conclusion, lanthanum sensitive $Ca^{2+}$ influx plays a significant role in Vibrio vulnificus cytolysin-induced platelet cytolysis and thrombocytopenia in V. vulnificus infection.

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SIMPLE VALUATION IDEALS OF ORDER TWO IN 2-DIMENSIONAL REGULAR LOCAL RINGS

  • Hong, Joo-Youn;Lee, Hei-Sook;Noh, Sun-Sook
    • Communications of the Korean Mathematical Society
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    • v.20 no.3
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    • pp.427-436
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    • 2005
  • Let (R, m) be a 2-dimensional regular local ring with algebraically closed residue field R/m. Let K be the quotient field of R and v be a prime divisor of R, i.e., a valuation of K which is birationally dominating R and residually transcendental over R. Zariski showed that there are finitely many simple v-ideals $m=P_0\;{\supset}\;P_1\;{\supset}\;{\cdotS}\;{\supset}\;P_t=P$ and all the other v-ideals are uniquely factored into a product of those simple ones. It then was also shown by Lipman that the predecessor of the smallest simple v-ideal P is either simple (P is free) or the product of two simple v-ideals (P is satellite), that the sequence of v-ideals between the maximal ideal and the smallest simple v-ideal P is saturated, and that the v-value of the maximal ideal is the m-adic order of P. Let m = (x, y) and denote the v-value difference |v(x) - v(y)| by $n_v$. In this paper, if the m-adic order of P is 2, we show that $O(P_i)\;=\;1\;for\;1\;{\leq}\;i\; {\leq}\;{\lceil}\;{\frac{b+1}{2}}{\rceil}\;and\;O(P_i)\;=2\;for\;{\lceil}\;\frac{b+3}{2}\rceil\;{\leq}\;i\;\leq\;t,\;where\;b=n_v$. We also show that $n_w\;=\;n_v$ when w is the prime divisor associated to a simple v-ideal $Q\;{\supset}\;P$ of order 2 and that w(R) = v(R) as well.

ON CYCLIC DECOMPOSITIONS OF THE COMPLETE GRAPH INTO THE 2-REGULAR GRAPHS

  • Liang, Zhihe
    • Journal of applied mathematics & informatics
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    • v.24 no.1_2
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    • pp.261-271
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    • 2007
  • The symbol C($m_1^{n_1}m_2^{n_2}{\cdots}m_s^{n_s}$) denotes a 2-regular graph consisting of $n_i$ cycles of length $m_i,\;i=1,\;2,\;{\cdots},\;s$. In this paper, we give some construction methods of cyclic($K_v$, G)-designs, and prove that there exists a cyclic($K_v$, G)-design when $G=C((4m_1)^{n_1}(4m_2)^{n_2}{\cdots}(4m_s)^{n_s}\;and\;v{\equiv}1(mod\;2|G|)$.

A Study on Fabrication and Characteristics of Nonvolatile SNOSFET EEPROM with Channel Sizes (채널크기에 따른 비휘방성 SNOSFET EEPROM의 제작과 특성에 관한 연구)

  • 강창수;이형옥;이상배;서광열
    • Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
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    • 1992.05a
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    • pp.91-96
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    • 1992
  • The nonvolatile SNOSFET EEPROM memory devices with the channel width and iength of 15[$\mu\textrm{m}$]${\times}$15[$\mu\textrm{m}$], 15[$\mu\textrm{m}$]${\times}$1.5[$\mu\textrm{m}$] and 1.9[$\mu\textrm{m}$]${\times}$1.7[$\mu\textrm{m}$] were fabricated by using the actual CMOS 1 [Mbit] process technology. The charateristics of I$\_$D/-V$\_$D/, I$\_$D/-V$\_$G/ were investigated and compared with the channel width and length. From the result of measuring the I$\_$D/-V$\_$D/ charges into the nitride layer by applying the gate voltage, these devices ere found to have a low conductance state with little drain current and a high conductance state with much drain current. It was shown that the devices of 15[$\mu\textrm{m}$]${\times}$15[$\mu\textrm{m}$] represented the long channel characteristics and the devices of 15[$\mu\textrm{m}$]${\times}$1.5[$\mu\textrm{m}$] and 1.9[$\mu\textrm{m}$]${\times}$1.7[$\mu\textrm{m}$] represented the short channel characteristics. In the characteristics of I$\_$D/-V$\_$D/, the critical threshold voltages of the devices were V$\_$w/ = +34[V] at t$\_$w/ = 50[sec] in the low conductance state, and the memory window sizes wee 6.3[V], 7.4[V] and 3.4[V] at the channel width and length of 15[$\mu\textrm{m}$]${\times}$15[$\mu\textrm{m}$], 15[$\mu\textrm{m}$]${\times}$1.5[$\mu\textrm{m}$], 1.9[$\mu\textrm{m}$]${\times}$1.7[$\mu\textrm{m}$], respectively. The positive logic conductive characteristics are suitable to the logic circuit designing.

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Characteristics analysis of Sub-50nm Double Gate MOSFET (Sub-50nm Double Gate MOSFET의 특성 분석)

  • 김근호;고석웅;이종인;정학기
    • Proceedings of the Korean Institute of Information and Commucation Sciences Conference
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    • 2002.11a
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    • pp.486-489
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    • 2002
  • In this paper, we have investigated characteristics of sub-50nm double gate MOSFET. From I-V characteristics, we obtained =510$\mu$A/${\mu}{\textrm}{m}$ at VMG=VDS=1.5V and VSG=3.0V. Then, the transconductance is 111$\mu$A/V, subthreshold slope is 86mV/dec and DIBL (Drain Induced Barrier Lowering) is 51.3mV. Also, we have presented that TCAD simulator is suitable for device simulation.

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Two Types of Voltage-activated Calcium Currents in Goldfish Horizontal Cells

  • Paik, Sun-Sook;Bai, Sun-Ho;Jung, Chang-Sub
    • The Korean Journal of Physiology and Pharmacology
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    • v.9 no.5
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    • pp.269-273
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    • 2005
  • In horizontal cells (HCs) that were freshly dissociated from goldfish retina, two types of voltagedependent calcium currents ($I_{Ca}$) were recorded using a patch-clamping configuration: a transient type current and a sustained type current. The cell was held at -40 mV, and the prepulse step of -90 mV was applied before command pulse between -65 and +55 mV. The transient $Ca^{2+}$ current was activated by depolarization to around -50 mV from a prepulse voltage of -90 mV lasting at least 400 ms and reached a maximal value near -25 mV. On the other hand, the sustained $Ca^{2+}$ current was induced by pre-inactivation for less than 10 ms duration. Its activation started near -10 mV and peaked at +20 mV. $Co^{2+}$ (2 mM) suppressed both of these two components, but nifedipine ($20{\mu}M$), L-type $Ca^{2+}$ channel antagonist, blocked only the sustained current. Based on the activation voltage and the pharmacolog$I_{Ca}$l specificity, the sustained current appears to be similar to L-type $I_{Ca}$ and the transient type to T-type $I_{Ca}$. This study is the first to confirm that transient type $I_{Ca}$ together with the sustained one is present in HCs dissociated from goldfish retina.

METALLICITIES OF GLOBULAR CLUSTRES M3 AND M5 FROM VI CCD PHOTOMETRY

  • Sohn, Young-Jong;Lee, Hyun-Chul
    • Journal of Astronomy and Space Sciences
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    • v.17 no.1
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    • pp.1-10
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    • 2000
  • To derive the metallicities of M3 and M5, we used the shape of red giant branch, horizontal branch magnitude, and red giant branch bump on the (V-I)-V color magnitude diagrams. [Fe/H] values ranging -1.46 ∼ -1.69 for M3, and -1.00 ∼ -1.49 for M5 are estimated. These values are in good agreements with the previously determined ones. This result leads the morphologies of red giant and horizontal branches on the (V-I)-V color magnitude diagrams can be good indirect metallicity indicators of galactic globular clusters.

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Inhibition of K+ outward currents by linopirdine in the cochlear outer hair cells of circling mice within the first postnatal week

  • Kang, Shin Wook;Ahn, Ji Woong;Ahn, Seung Cheol
    • The Korean Journal of Physiology and Pharmacology
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    • v.21 no.2
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    • pp.251-257
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    • 2017
  • Inhibition of $K^+$ outward currents by linopirdine in the outer hair cells (OHCs) of circling mice (homozygous (cir/cir) mice), an animal model for human deafness (DFNB6 type), was investigated using a whole cell patch clamp technique. Littermate heterozygous (+/cir) and ICR mice of the same age (postnatal day (P) 0 -P6) were used as controls. Voltage steps from -100 mV to 40 mV elicited small inward currents (-100 mV~-70 mV) and slow rising $K^+$ outward currents (-60 mV~40 mV) which activated near -50 mV in all OHCs tested. Linopirdine, a known blocker of $K^+$ currents activated at negative potentials ($I_{K,n}$), did cause inhibition at varying degree (severe, moderate, mild) in $K^+$ outward currents of heterozygous (+/cir) or homozygous (cir/cir) mice OHCs in the concentration range between 1 and $100{\mu}m$, while it was apparent only in one ICR mice OHC out of nine OHCs at $100{\mu}m$. Although the half inhibition concentrations in heterozygous (+/cir) or homozygous (cir/cir) mice OHCs were close to those reported in $I_{K,n}$, biophysical and pharmacological properties of $K^+$ outward currents, such as the activation close to -50 mV, small inward currents evoked by hyperpolarizing steps and TEA sensitivity, were not in line with $I_{K,n}$ reported in other tissues. Our results show that the delayed rectifier type $K^+$ outward currents, which are not similar to $I_{K,n}$ with respect to biophysical and pharmacological properties, are inhibited by linopirdine in the developing (P0~P6) homozygous (cir/cir) or heterozygous (+/cir) mice OHCs.