• Title/Summary/Keyword: Capillary action

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Capillary Force Lithographic Patterning of a Thermoplastic Polymer Layer for Control of Azimuthal Anchoring in Liquid Crystal Alignment

  • Kim, Hak-Rin;Shin, Min-Soo;Bae, Kwang-Soo;Kim, Jae-Hoon
    • Journal of Information Display
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    • v.9 no.1
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    • pp.14-19
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    • 2008
  • We demonstrated the capillary force lithography (CFL) method for controlling the azimuthal anchoring energy of a liquid crystal (LC) alignment layer. When a thermoplastic polymer film is heated to over the glass transition temperature, the melted polymer is filled into the mold structure by the capillary action and the aspect ratio of the pattern is determined by the dewetting time of the CFL process. Here, the proposed method showed that the azimuthal anchoring energy of the LC alignment layer could be simply controlled by the surface relief patterns which were determined by the dewetting times during the CFL patterning.

A Capillary Electrochromatographic Microchip Packed with Self-Assembly Colloidal Carboxylic Silica Beads

  • Jeon, In-Sun;Kim, Shin-Seon;Park, Jong-Man
    • Bulletin of the Korean Chemical Society
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    • v.33 no.4
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    • pp.1135-1140
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    • 2012
  • An electrochromatographic microchip with carboxyl-group-derivatized mono-disperse silica packing was prepared from the corresponding colloidal silica solution by utilizing capillary action and self-assembly behavior. The silica beads in water were primed by the capillary action toward the ends of cross-patterned microchannel on a cyclic olefinic copolymer (COC) substrate. Slow evaporation of water at the front of packing promoted the self-assembled packing of the beads. After thermally binding a cover plate on the chip substrate, reservoirs for sample solutions were fabricated at the ends of the microchannel. The packing at the entrances of the microchannel was silver coated to fix utilizing an electroless silver-plating technique to prevent the erosion of the packed structure caused by the sudden switching of a high voltage DC power source. The electrochromatographic behavior of the microchip was explored and compared to that of the microchip with bare silica packing in basic borate buffer. Electrophoretic migration of Rhodamine B was dominant in the microchip with the carboxyl-derivatized silica packing that resulted in a migration approximated twice as fast, while the reversible adsorption was dominant in the bare silica-packed microchip. Not only the faster migration rates of the negatively charged FITC-derivatives of amino acids but also the different migration due to the charge interaction at the packing surface were observed. The electrochromatographic characteristics were studied in detail and compared with those of the bare silica packed microchip in terms of the packing material, the separation potential, pH of the running buffer, and also the separation channel length.

Characterization of Taurine Transport in Conditionally Immortalized Rat Brain Capillary Endothelial Cell Lines (조건적 불사화 흰쥐 뇌 모세혈관 내피세포주에서 Taurine 수송 특성)

  • 강영숙;이나영
    • Biomolecules & Therapeutics
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    • v.10 no.2
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    • pp.99-103
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    • 2002
  • Taurine has a neuroprotective action from oxidative stress in neural cell. In the present study, we studied taurine transport under basal and stressed conditions in conditionally immortalized rat brain capillary endothelial cell line (TR-BBB13) in vitro. The uptake of[$^3{H}$]taurine in the TR-BBB13 was increased by time-dependently and dependent on both Na$^{+}$ and Cl/ sup -/. Furthermore, $\beta$-alanine strongly inhibited the uptake of [TEX>$^3{H}$]taurine in the TR-BBB13. To study the effcts of oxidative stress on taurine transport, we used diethyl maleate (DEM) and lipopolysccharide (LPS). Diethyl maleate (DEM, $300\Mu\textrm{M}$) significantly reduced uptake of [TEX>$^3{H}$]taurine by time-dependently until 8 hr exposure in TR-BBB 13. But, the [TEX>$^3{H}$]taurine uptake was not changed by lipopolysccharide (LPS, 10 ng/ml) in TR-BBB13.3.

Friction Reduction Properties of Evaporation Coated Petroleum and Silicone Oil Lubricants (증발 코팅법으로 증착된 광유와 실리콘 오일 윤활제의 마찰 저감 특성)

  • Yoo, Shin Sung;Kim, Dae Eun
    • Journal of the Korean Society for Precision Engineering
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    • v.30 no.8
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    • pp.864-869
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    • 2013
  • As the size of mechanical components decreases, capillary forces and surface tension become increasingly significant. A major problem in maintaining high reliability of these small components is that of large frictional forces due to capillary action and surface tension. Unlike the situation with macro-scale systems, liquid lubrication cannot be used to reduce friction of micro-scale components because of the excessive capillary and drag forces. In this work, the feasibility of using evaporation to coat a thin film of organic lubricant on a solid surface was investigated with the aim of reducing friction. Petroleum and silicone oils were used as lubricants to coat a silicon substrate. It was found that friction could be significantly reduced and, furthermore, that the effectiveness of this method was strongly dependent on the coating conditions.

Anti-inflammatory action of p-methoxycinnamic acid (p-Methoxycinnamic acid의 소염작용)

  • 신국현;이은방;우원식
    • YAKHAK HOEJI
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    • v.14 no.3_4
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    • pp.45-50
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    • 1970
  • Anti-infalmmatory action of p-methoxycinnamic acid (p-MCA) was investigated. p-MCA showed a significant decrease in carrageenin and acetic acid induced edema of the rat hind paw, and increased capillary permeability by anaphylaxis and chemical mediators of pontamine sky blue in the mouse peritoneal cavity. It, however, showed only weak inhibitory effect on cotton pellet-induced granuloma formation of the rat.

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Effects of Ethanol Extract of Rehmanniae Radix(RREE) on Resting and Action Potential of Rabbit Sinoatrial Node and Papillary Muscle (Rehmanniae Radix에 의한 가토 동방결절 및 유두근의 활동전압의 변동)

  • Hwang, Bo-Sang;Koh, Sang-Don;Shin, Hong-Kee;Kim, Kee-Soon
    • The Korean Journal of Physiology
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    • v.19 no.2
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    • pp.127-137
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    • 1985
  • The present study was undertaken in order to investigate effect of ethanol extract of Rehmanniae radix(RREE) on electrophysiology of sinus node and papillary muscle. Rehmanniae radix is a herbal medicine which has been known to have diuretic, antipyretic, hemopoietic and cardiotonic effects. Action potentials were recorded by means of glass capillary microelectrode(technique) in rabbit sinoatrial nodal cells and papillary muscle cells which were superperfused with either tyrode solution or tyrode solutions containing different amount of RREE. The results obtained were as follows ; 1) In both central and peripheral nodal cells maximum diastolic potential (MDP) and amplitude of action potential (APA) were not affected by RREE. 2) Action potential duration as expressed $APD_{60}$(time to 60% repolarization) of central and peripheral pacemaker cells were significantly prolonged following perfusion with tyrode solution containing 0.1% RREE. 3) The rates of spontaneous firing from central pecemaker cell were decreased by RREE at concentration of 0.05% and 0. 1% while spontaneous rhythm of perinodal cell was decreased by 0.1% RREE. 4) The action potential duration of papillary muscle as expressed $APD_{60}$ were prolonged by 0.1% RREE.

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?Experimental Study on the Effects of Zanthoxyli Fructus and Fagarae mandshuricae Fructus (천초(川椒) 및 산초(山椒)의 효능(?能)에 관(關)한 실험적(實驗的) 연구(硏究))

  • O, Han-Gyun;Won, Jong-Hun;Jeong, Gyu-Man
    • The Journal of Pediatrics of Korean Medicine
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    • v.4 no.1
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    • pp.1-17
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    • 1990
  • ?In order to investigate effects of Zanthoxyli Fructus (Sample-A) and Fagarae mandshuricae Fructus (Sample-B), experimental study was performed through observation on isolated - ileum analgesic, hypothermal, anti-pyretic, anti-inflammatory, capillary permeability, blood flow rate, blood pressure and respiratory works. The results were as follows; 1. In spontaneous movement of mice isolated-ileum, both samples were noted to have strong inhibitory action after temporary contraction, and to show antagonism against acetylcholine chloride and barium chloride. 2. Both samples were showed to have antihistamin work on guinea pig isolated-ileum 3. In analgesic work by the acetic acid method, only Fagarae mandshuricae Fructus was proved to have significant analgesic effect in mice. 4. Both sample groups indicated anti-pyretic and anti-inflammatory effect. 5. Both samples were noted to have inhibitory effect against capillary permeability ?rise in mice. ?6. Both samples were noted to have dose-dependent falling effect on blood pressure in rabbits.

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Model on the Capillary Action-Induced Dynamics of Contact Lens (모세관 작용에 의한 콘택트 렌즈의 운동 모델)

  • Kim, Dae-Soo
    • Journal of Korean Ophthalmic Optics Society
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    • v.6 no.2
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    • pp.85-97
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    • 2001
  • A mathematical model was proposed to analyze the damped motion of contact lens which is initially displaced from the equilibrium position. The model incorporates the differential equations and their numerical solution program, based on the formulations of restoring force arising from the capillary action in the tear-film layer between the lens and cornea. The model predicts the capillary action induced surface tension, time dependence of displacement of lens when it is released from the equilibrium position. It seems that the motion of lens is similar to the typical over-damped oscillation caused by the large viscous friction in the liquid layer between the cornea and lens. The effect of variables such as base curves, lens diameters and thickness of tear film layer were illustrated by the computer simulation of the derived program. The time required for the lens to return to the original position increases as the liquid layer thickness increases and it decreases as the diameter of lens increases. With the certain value of base curve the time interval is found to be minimum. The free vibrations of lenses were also simulated varying the parameters such as base curve, diameter, layer thickness. The resonant frequencies are inversely proportional to the liquid layer thickness and it increases as the lens diameter increases. The resonant frequency of lens has a maximum when the diameter is of certain value. If the external impulse or force of the same frequency as the natural frequency of contact lens acted on the cornea in vivo it may cause an excessive movement and thus it might cause the distortion 10 the lens or be pulled off the eye.

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Anti-arthritic Effect of Glucosamine and Oriental Herbal Composition

  • Cho, Seong-Wan;Kim, Young-Il;Lee, Young-Jae;Cho, Hyoung-Kwon;Kim, Young-Kwon
    • Biomedical Science Letters
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    • v.14 no.2
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    • pp.97-103
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    • 2008
  • This study was conducted to investigate the effect of an anti-inflammatory and analgesic action of the glucosamine HCl (Glucosamine) and SH-1 (Glucosamine + Oriental herbal composition combined group). Male sprague-Dawley rats $(200{\sim}250g)$ and ICR mice $(20{\sim}30g)$ were randomized and these experimental groups were divided into 4 groups. Two control group were given as negative control (saline) and positive control (Ibuprofen, 100 mg/kg) and two groups given as oral administration of Glucosamine (320 m/kg) and SH-1. Carrageenan induced paw edema test, hot plate method, croton oil induced granuloma, capillary permeability test and acetic acid writhing syndrome were also shown to be comparable in the SH-1 group to anti-inflammatory drug group such as positive control group (Ibuprofen). Although further studies should be performed to confirm the effects of SH-1, present results suggest that the combined administration of SH-1 have potential action in anti-inflammatory and analgesic action. It could be applicable for the improvement of arthritic symptoms as a new diet-supplement.

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Effects of Dopamine on the Contractility and Action Potential of the Rabbit Papillary Muscle (Dopamine이 토끼 유두근의 수축력과 활동전압에 미치는 영향)

  • Huh, In-Hoi;Park, Jong-Wan
    • YAKHAK HOEJI
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    • v.32 no.6
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    • pp.402-414
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    • 1988
  • In order to clarify the receptor types and mechanisms underlying the positive inotropic effect of dopamine on the mammalian ventricular myocardium, the action potential, its first derivatives and isometric contraction of the rabbit papillary muscle were recorded using a force transducer and glass capillary microelectrodes filled with 3M KCl. The results were as follows; (1) In normal Tyrode solution, the contractile force was increased and duration of action potential was shortened with increments of dopamine concentration ($10^{-6}-10^{-4}M$). (2) The dose-response curve was markedly shifted to the right by pretreatment with reserpine (5mg/kg i.p., 24hrs prior to the experiment). (3) In 19mM $K^+-Tyrode$ solution, the duration of action potential, maximum rate of rise (V_{max}) of action potential and overshoot were significantly increased with increments of dopamine concentration ($10^{-6}-10^{-4}M$). (4) The inotropic effect of dopamine on the rabbit papillary muscle pretreated with reserpine was antagonized by atenolol ($10^{-6}M$), but not by phentolamine ($3{\times}10^{-6}M$). (5) In rabbit papillary muscle partially depolarized by 19mM $K^+-Tyrode$ solution, slow electrical response (calcium mediated action potential) as well as contraction were restored by dopamine ($10^{-4}M$); this restoration was blocked by calcium antagonists ($3{\times}10^{-5}M$ $LaCl_3{\cdot}6H_2O$, $3{\times}10^{-6}M$ diltiazem) or ${\beta}-adrenoceptor$ antagonist ($3{\times}10^{-6}M$ atenolol), but not affected by ${\alpha}-adrenoceptor$ antagonist ($10^{-5}M$ phentolamine, $3{\times}10^{-6}M$ yohimbine) or vascular dopaminergic receptor antagonist ($10^{-5}M$ haloperidol). The above results may be interpreted as that the positive inotropic effect of dopamine through both direct and indirect action are caused by increase in slow inward current ($Ca^{2+}$ influx into themyocardial cell), and the direct action is mainly due to the stimulation of ${\beta}-adrenoceptors$ in the rabbit papillary muscle.

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