• Proceedings of the Korean Society of Applied Pharmacology
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• 2000.04a
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• pp.17-19
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• 2000

Heterotrimeric G Proteins transduce ligand binding to a wide variety of seven transmembrane cell surface receptors into intracellular signals. The currently accepted model for the activation of G protein suggests that ligand-activated receptor accelerates GDP-GTP exchange reactions on the ${\alpha}$ subunit of the heterotrimeric G protein. At least seventeen distinct isoforms of the G${\alpha}$ subunit protein have been identified in mammalian organisms. Among them, the G${\alpha}$q family consists of five members whose ${\alpha}$ subunits show different expression patterns. G${\alpha}$q and G${\alpha}$11 seem to be almost ubiquitously expressed, whereas G${\alpha}$14 is predominantly expressed in spleen, lung, kidney and testis. G${\alpha}$16 and its murine counterpart G${\alpha}$15 are expressed in hematopoietic cells and has been shown to couple a wide variety of receptors to phosphoinositide-specific phospholipase C activity. Beta-isoforms of phospholipase C were shown to be activated by all members of G${\alpha}$q family, i.e., G${\alpha}$q, G${\alpha}$11, G${\alpha}$l4 and G${\alpha}$16 subunits either in reconstitution system. or in experiments using cDNA transfection with intact Cos-7 cells.

• Journal of Veterinary Clinics
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• v.14 no.1
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• pp.30-36
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• 1997

It is well estabilished that IL-4, IL-6, $IFN{\gamma}$ and immunoglobulin production are increased as a consequence of advancing age, and endothelial cells increase their expression of pro-inflammatory surface protein, such as ICAM-1, as a consequence of contact with inflammatory cytokines, including IL-1, $TNF{\alpha} or INF{\gamma}.$ This study was designed to define the relationship between age-associated changes of cytokines and immunoglobulin production and ICAM-1 expression in aged mice. Serum from aged mice had elevated IL-6 and immunoglobulin levels compared to mature adult controls and activation-induced production of $IFN{\gamma}$ of splenocytes from aged mice were increased above normal adult level. By immunoperoxidase staining, ICAM-1 in hearts of normal adult mice was expressed occasionally at low levels, but in aged mice, the number of positive blood vessels for ICAM-1 were increased and also the immunoreactivity were stronger. Therefore, these finding indicate that the altered expression of ICAM-1 eith normal aging may actually be correlative to these age-related changes in cytokiness and immunoglobulin production.

• Journal of the Korean Ceramic Society
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• v.35 no.5
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• pp.443-450
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• 1998

Layered double hydroxides(LDHs) [{{{{ {Mg }_{1-x } }}{{{{ {Al }_{x } }}({{{{ {OH}_{2 } }})]ζ+({{{{ {CO }`_{3 } ^{2- } ){ }_{x/2 } }}$.${{{{ { yH}_{2 }O }} wioth variation of layer charge densitywere synthesized by co-precipitation methdo since their charge densities have a very important role to be det-ermined the physicochemical properties of layered materials. The XRD IR and thermal studies of them were discussed and the kinetic study for the decarbonation reaction was also carried out. From the results of XRD analysis we found that the lattice parameter and the unit cell volume were linearly decreased with the amount of Al substituents(x) in the vicinity of x=2∼10${\times}$1/3${\times}$10-1 but they had nearly constant values when the x are far from these vicinit. The activation energies for the decarbonation reaction of x=6.8, 10${\times}$1/3${\times}${{{{ { 10}^{-1 } }} were estimated to be 47.0, 37.6, 39.3 kcal/mol The specific surface areas(90-120 m2/g) of stable hy-drotalcite-type LDHs were dractically decreased with increasing of layer charge density.

• Maxillofacial Plastic and Reconstructive Surgery
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• v.37
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• pp.5.1-5.4
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• 2015

Dry eye syndrome is a relatively common disease of the tears and ocular surfaces that results in discomfort, visual disturbance, and tear film instability with possible damage to the ocular surfaces. Microvascular submandibular gland (SMG) transfer offers a surgical alternative for a permanent autologous substitution of tears using the basal secretion of a transplanted SMG. Long-term follow-up reveals that this technique is a lasting and effective solution for patients with severe dry eye syndrome. The uncomfortable symptoms were relieved, and the frequency of use of pharmaceutical tear substitutes was reduced. Objective examination showed significant improvement in tear film and some features of ocular surface such as breakup time of tear film and corneal staining. Patients may suffer from obstruction of Wharton's duct or epiphora after surgery. Activation of secretion-related receptors could improve the early hypofunction of the denervated SMG and prevent the duct obstruction. Reduction surgery, partial SMG transplantation, uses of atropine gel or Botulinum toxin A could be the choices of treatment for epiphora.

• Proceedings of the Korean Vacuum Society Conference
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• 2014.02a
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• pp.386.1-386.1
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• 2014

The ionic polymer-metal composite (IPMC), a type of electro-active polymer material, has received enormous interest in various fields such as robotics, medical sensors, artificial muscles because it has many advantages of flexibility, light weight, high displacement, and low voltage activation, compare to traditional mechanical actuators. Mostly noble metal materials such as gold or platinum were used to form the electrode of an IPMC by using electroless plating process. Furthermore, carbon-based materials, which are carbon nanotube (CNT) and reduced graphene-CNT composite, were used to alter the electrode of IPMC. To form the electrode of IPMC, we employ the synthesized graphene on copper foil by chemical vapor deposition method and use the transfer process by using a support of PET/silicone film. The properties of graphene were evaluated by Raman spectroscopy, UV/Vis spectroscopy, and 4-point probe. The structure and surface of IPMC were analyzed via field emission scanning electron microscope. The fabricated IPMC performance such as displacement and operating frequency was measured in underwater.

• Korean Journal of Materials Research
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• v.9 no.7
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• pp.675-679
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• 1999

An investigation was performed to prepare spherical cobalt powder with about particle size of 400nm from aqueous cobalt hydroxide slurry under hydrothermal reduction conditions using palladium chloride as a catalyst. The reduction kinetics was in good agreement with a surface reaction core model equation. and the activation energy obtained from Arrhenius plots was 55.6 KJ/mol at the temperature range of $145~195^{\circ}C$. Additionally, the study showed that the cobalt reduction rate is proportional to the initial hydrogen pressure with a reaction order of n=0.63. which corresponds to the gas chemisorption reaction type.

• Resources Recycling
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• v.11 no.4
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• pp.37-43
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• 2002

As the consumption of galvanized steels in cans and automobiles and the quantity of scraps increase, the recycling problems of EAF dust become a important problem. Valuable metals such as Fe, Zn, Pb are of continued interest to metallurgists. To recover the valuable metal and to remove the toxicity of EAF dust, high temperature smelting process is or researching as a pilot scale. The Reduction kinetics of Zn in EAF dust is so important in a view of the economic consideration of the process. In this study, the kinetics behavior of Zn in EAF dust were measured as a point of application in high temperature smelting process. The rate control step in ZnO and franklinite is revealed to be chemical reaction on the reaction surface.

• International Journal of Contents
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• v.6 no.1
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• pp.41-46
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• 2010

The aim of this study was to investigate the effect of different shoe-heel heights on the surface electromyographic (EMG) activity of vastus medialis (VM) and vastus lateralis (VL) during treadmill walking in female patients with patellofemoral pain (PFP). Nineteen women with PFP participated in this research. EMG signals were recorded from the VM and VL of both sides and were compared during the treadmill walking. The subjects walked on a treadmill wearing shoes of three different heel heights: 1 cm, 3 cm and 7 cm. Each subject walked on a treadmill for five minutes at a speed of 2 km/hour with three minutes resting intervals between consecutive trials. The data were analyzed by one-way repeated-measures analysis of variance. The results of the present study indicate that EMG data of the VM and VL of female patients with PFP did improve with an increase in the height of the shoe heel, which were statistically significant. Additionally, the EMG activity of VM increased more dramatically than that of VL associated with the task of walking with high-heeled shoes on the treadmill. This study suggests that the type of high-heeled shoes is related to the VM and VL muscle activation patterns contributing to knee joint pathologies in female patients with PFP.

• Journal of Energy Engineering
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• v.6 no.1
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• pp.34-40
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• 1997

This study aims to investigate the application possibility on natural gas in relation to the catalytic combustion of methane on Pd/cordierite catalyst which is currently used as an automobile converter catalyst. The surface area of the catalyst tested was determined to be about 18.7㎡/g and to keep stable condition in structure at mid-high temperatures. The activation energy for methane combustion reaction was estimated to be 19.2 kcal/mol and a hysterisis on the catalyst activity was observed in terms of the catalyst deactivation as the reaction temperature was varied for the methane combustion. On Pd/cordierite catalyst, The characteristics of methane combustion were studied as functions of space velocity and air/fuel ratios below 700$^{\circ}C$.

• Journal of The Korean Society of Integrative Medicine
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• v.6 no.2
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• pp.117-123
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• 2018

Purpose : The purpose of this study was to investigate the effect of increased brain activity on the muscle endurance and the effect of brain activation through the combination of transcranial direct current stimulation and aerobic exercise on elderly woman. Methods : To investigate the effect of the muscle endurance on right leg, muscle endurance was evaluated by measuring the surface EMG of the muscles of the rectus femoris, biceps femoris, tibialis anterior, and gastrocnemius muscle. Results : There was a significant difference in the pre and post comparisons of muscle endurance on rectus femoris, biceps femoris, tibialis anterior muscle (p<.05). Difference of Combination of transcranial direct current stimulation and aerobic exercise group median frequency was smaller than control group (p<.05). There was not a significant difference in the pre and post comparisons of muscle endurance on biceps femoris, and gastrocnemius muscle. Difference of Combination of transcranial direct current stimulation and aerobic exercise group median frequency was showed a similar pattern. Conclusion : Through these results, It was found that increasing the brain activity by the transcranial direct current stimulation improves the exercise capacity on the elderly women. Combination of transcranial direct current stimulation and aerobic exercise maybe applied as an effective treatment for improving muscular endurance.