• Honam Mathematical Journal
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• v.32 no.4
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• pp.689-699
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• 2010

We discuss in this paper the notions of extended negative quadrant dependence and its properties. We study a class of bivariate uniform distributions having extended negative quadrant dependence, which is derived by generalizing the uniform representation of a well-known Farlie-Gumbel-Morgenstern distribution. Finally, we also study the limit behavior on the extended negative quadrant dependence.

• Journal of the Korean Institute of Electrical and Electronic Material Engineers
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• v.16 no.10
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• pp.914-922
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• 2003

The FFS (fringe-field switching) mode was known to exhibit both a wide viewing angle and high transmittance, especially when using a liquid crystal with negative dielectric anisotropy. We have studied cell gap-dependent electrode-optic characteristics of the FFS mode using the LC with negative dielectric anisotropy. In case of a small cell gap of 2 ${\mu}$m, the transmittance at the center of pixel and common electrodes is relatively low because effect of surface anchoring that holds the LC to the initial state is larger than that in a large cell gap of 4 .urn such that the LCs in those regions cannot rotate enough. However, in case of a large cell gap of 4 .urn, the effect of surface anchoring becomes relatively small so that the LCs at the center of pixel and common electrode can be twisted enough by applied voltage, giving rise to high transmittance. Therefore, we can conclude that the light efficiency is dependent on the cell gap.

• The Korean Journal of Physiology and Pharmacology
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• v.2 no.6
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• pp.715-724
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• 1998

Frequency-force relationships (FFR) were studied in electrically field stimulated rat left atria (LA) by reducing the stimulation frequency from resting 3 Hz to test frequencies (0.1-1 Hz) for 5 minutes. The twitch amplitudes of LA elicited the typical negative staircases with 3-phased changes: the initial rapid increase, the second decrease and the following plateau at test frequencies. Verapamil $(3{\times}10^{-5}\;M)$ pretreatment elicited frequency-dependent suppression of the twitch amplitudes, exaggerating the negative staircase. Monensin pretreatment enhanced not the peak but the plateau amplitudes in a concentration-dependent manner. When the $Na^+-Ca^{2+}$ exchange was blocked by $Na^+\;and\;Ca^{2+}$ depletion in the Krebs Hensleit buffer (0 $Na^+-0\;Ca^{2+}$ KHB), the twitch amplitudes increased in a frequency-dependent manner, changing the negtive staircase into the positve one. Meanwhile, the 0 $Na^+-0\;Ca^{2+}$ KHB applicationinduced enhancement was strongly suppressed by caffeine (5 mM) pretreatment. Only dibucaine among the local anesthetics increased the basal tone during frequency reduciton. There were no differences in $^{45}Ca$ uptakes between 0.3 Hz and 3 Hz stimulation except at 1 min when it was significantly low at 0.3 Hz than 3 Hz, illustrating net $Ca^{2+}$ losses. Monensin pretreatment enhanced the rate of this $Ca^{2+}$ loss. Taken together, it is concluded that $Na^+-Ca^{2+}$ exchange extrudes more SR released $Ca^{2+}$ out of the cell in proportion to the frequency, resulting in the negative rate staircase in the rat LA.

• Journal of the Korean Statistical Society
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• v.29 no.3
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• pp.261-268
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• 2000

Let {Xn,n$\geq$1} be a sequence of pairwise negative quadrant dependent(NQD) random variables and let {an,n$\geq$1} and {bn,n$\geq$1} be sequencesof constants such that an$\neq$0 and 0$\infty$. In this note, for pairwise NQD random varibles, a general weak law of alrge numbers of the form(∑│aj│Xj-$\upsilon$n)/bnlongrightarrow0) is established, where {νn,n$\geq$1} is a suitable sequence. AMS 2000 subject classifications ; 60F05

• 한국정보디스플레이학회:학술대회논문집
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• 2003.07a
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• pp.539-542
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• 2003

We have studied cell gap-dependent electrode-optic characteristics of the FFS mode using the LC with negative dielectric anisotropy. In case of a small cell gap of 2 ${\mu}m$, the transmittance at the center of pixel and common electrodes is low due to stronger influence of surface anchoring that holds the LC to the initial state than twisting force induced by neighboring LCs. In case of a large cell gap of 4 ${\mu}m$, the influence of surface anchoring force becomes weak so that the LCs at the center of pixel and common electrode can be twisted enough by applied voltage, giving rise to high transmittance. Therefore, we conclude that the light efficiency in the device is dependent on the cell gap.

• Journal of Microbiology and Biotechnology
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• v.30 no.3
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• pp.341-351
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• 2020

To shed light on the genetic differences among food-originated coagulase-negative Staphylococcus (CNS), we performed pan-genome analysis of five species: Staphylococcus carnosus (two strains), Staphylococcus equorum (two strains), Staphylococcus succinus (three strains), Staphylococcus xylosus (two strains), and Staphylococcus saprophyticus (one strain). The pan-genome size increases with each new strain and currently holds about 4,500 genes from 10 genomes. Specific genes were shown to be strain dependent but not species dependent. Most specific genes were of unknown function or encoded restriction-modification enzymes, transposases, or prophages. Our results indicate that unique genes have been acquired or lost by convergent evolution within individual strains.

• The Transactions of the Korean Institute of Electrical Engineers
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• v.36 no.6
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• pp.418-423
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• 1987

In the course of the investigation to the field dependent electrical conducation mechanism in polypropylene, an abnormal conduction phenomena such as voltage controlled negative resistance charateristics has been observed at the junction of two regions charateriged by schottky effect and space charge effect respectively. This abnormal characteristics was observed initially about 110MV / m of the field strength and at 25 , however, the field strength where it observed was decreased and the apparent feature of negative charateristics was less pronounced as increasing ambient temperature. Although the observations of analogous characteristics in other materials such as polyethylene, polymethylemethactylate, and polystyrene have already been reported together with plausible explanation by Toureille and others, however, it was found that the proposed concept by those authors was little use to the present observations for quantitative discussions. Accordingly we tried to adapt another conceptual discussion based on Gibbons's formulation pertaing to the saturatio trend of the field dependent drift velocity of carriers towards the thermal velocity corresponding to the ambient temperature so that the quantitative explanatio on the observed facts has been succeeded to some estent of reasonable acceptance.

• Animal cells and systems
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• v.9 no.3
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• pp.173-179
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• 2005

Cyclic-AMP-dependent protein kinase (PKA) seems to function as a negative regulator of the c-Jun $NH_2-terminal$ kinase (JNK) signaling pathway. We demonstrate here that the activity of the PKA catalytic subunit (PKAc) is reduced in apoptotic PC12 pheochromocytoma cells. Apoptotic progress was inhibited by dibutyryl cyclic AMP (dbcAMP), an analog of cAMP. The rescue by dbcAMP was attributable to inhibition of the JNK but not of the p38 signaling pathway, due to the induction of PKA activity. JNK was present in immunocomplexes of PKAc, and PKAc phosphorylated JNK in vitro. Presence of p38 kinase, however, was not prominent in immunocomplexes of PKAc. Our data suggest that JNK is a target point of negative regulation by PKAc in the JNK signaling pathway.

• Journal of the Chungcheong Mathematical Society
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• v.31 no.3
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• pp.343-352
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• 2018

We study the complete convergence for sequences of dependent random variables in Hilbert spaces. Results are obtained for negatively associated random variables and ${\phi}$-mixing random variables in Hilbert spaces.

• Korean Journal of Veterinary Research
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• v.41 no.3
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• pp.311-317
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• 2001

In this work we have investigated the physiological effects of $MgCl_2$ in isolated atrium, papillary muscle, perfused heart and anesthesized guinea pig, The addition or infusion of $MgCl_2$ (0~20 mM or mg/kg) to perfused hearts and to anesthesized guinea pigs induced a marked and dose-dependent negative chronotropic effect. The sinoatrial node automaticity could also be reduced by $MgCl_2$. The addition of $MgCl_2$to isolated atria and to papillary muscles induced a marked and dose-dependent negative inotropic effect. The threshold voltage could be increased by $MgCl_2$in papillary muscle. Increasing $MgCl_2$ shortened the action potential duration (APD) in dose-dependent manner at 30% ($APD_{30}$) and 90% repolarization ($APD_{90}$) measured with conventional microelectrode technique in papillary muscle. In anesthesized guinea pig, the magnesium infusion resulted in a dose-dependent drop in blood pressure. These results suggested that magnesium is closely associated with cardiac physiological condition and exerts antiarrhythmic activities.