• Journal of Korean Society for Atmospheric Environment
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• v.16 no.5
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• pp.453-467
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• 2000

The aim of this research is to collect and characterize fine particles (FPM:$\leq$2.5${\mu}{\textrm}{m}$) and coarse particles (CPM: 2.5~10${\mu}{\textrm}{m}$) using a low volume air sampler provided by the IAEA, at urban (Taejon) and rural area(Wonju) for a period of about two years(April 1996 to May 1998) and to promote a use of nuclear analytical techniques for air pollution studies. For the collection of airborne particulate matter (PM(sub)10), the Gent stacked filter unit sampler and polycarbonate membrane filters were employed. The concentration of trace elements in collected APM samples were determined byu instrumental Neutron Activation Analysis. For validation of the analytical data, internal quality control were implemented by using both the comparison of the analytical results of standard reference materials(NIST SRM 1648) and interlaboratory comparison for proficiency test (NAT-3). The standard uncertainty was less than 15% and Z-score of two samples were within $\pm$1. The monitoring of (PM(sub)10) mass concentration and elemental concentrations were carried out weekly. The average mass concentration of (PM(sub)10) in urban and rural areas were 59.2$\pm$36.5$\mu\textrm{g}$/㎥ and 41.4$\pm$23.7$\mu\textrm{g}$/㎥, respectively. To investigate the emission source, the enrichment factors were calculated for the fine and coarse particle fractions at two sites, respectively and these values were classified for anthropogenic and soil origin elements.

• Korean Journal of Food Science and Technology
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• v.20 no.5
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• pp.650-658
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• 1988

The mobilization of proteins in the cotyledons of germinating soybean seeds (Glycine mar [L.] Merr.) and seedlings was studied by using light microscopy and transmission electron microscopy. The cotyledon tissues of soybean. were packed with protein bodies(diameter $0.1-15{\mu}m$) where storage protein of soybean is deposited. Degradation of protein bodies started in the epidermis and vascular tissues. After swelling of the protein bodies, autolysis of storage proteins began while the external membrane remained unbroken. Hydrolysis of proteins could be internal or peripheral and fusion might begin before complete protein degradation. Possible instances of vacuolar fusion were encountered in some cells. In all cases, the result of degradation was the same; the central vacuole of the cell. At the late stages of seedling growth, breakdown of tonoplast was observed in some cells.

• The Korean Journal of Physiology and Pharmacology
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• v.8 no.3
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• pp.161-165
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• 2004

Exogenous carbon monoxide (0.2%) increases L-type calcium $(Ca^{2+})$ current in human jejunal circular smooth muscle cells. The stimulatory effect of carbon monoxide (CO) on L-type $Ca^{2+}$ current is inhibited by pre-application of L-NNA, a classical competitive inhibitor of nitric oxide synthase (NOS) with no significant isoform selectivity (Lim, 2003). In the present study, we investigated which isoform of NOS affected CO induced stimulation of L-type $Ca^{2+}$ current in human jejunal circular smooth muscle cells. Cells were voltage clamped by whole-cell mode patch clamp technique, and membrane currents were recorded with 10 mM barium as the charge carrier. Before the addition of CO, cells were pretreated with each inhibitor of three NOS isoforms for 15 minutes. CO-stimulating effect on L-type $Ca^{2+}$ current was partially blocked by N-(3-(Amino-methyl) benzyl) acetamidine 2HCl (1400W, an iNOS inhibitor). On the other hand, 3-bromo-7-nitroindazole (BNI, a nNOS inhibitor) or $N^5-(1-Iminoethyl)-L-ornithine$ dihydrochloride (L-NIO, an eNOS inhibitor) completely blocked the CO effect. These data suggest that low dose of exogenous CO may stimulate all NOS isoforms to increase L-type $Ca^{2+}$ channel through nitric oxide (NO) pathway in human jejunal circular smooth muscle cells.

• Journal of Korean Society of Environmental Engineers
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• v.37 no.11
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• pp.607-618
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• 2015

This study was conducted to suggest hydraulic modification for improving evenness of inlet flow distribution into side stream type low-pressure MF (microfiltration) module using CFD (computational fluid dynamics) simulation and PIV (particle image velocimetry) techniques. From the results of CFD simulation for various typed inlet structure, it was investigated that installing internal orifice baffle in inlet the distribution channel could improve the evenness of inlet flow distribution over about 40%. Also, from the results of PIV measurements which were carried out for verifying the CFD simulation, it was observed that the momentum of the water body coming from the opposite side of the inlet was relatively larger. This momentum would generate strong shear force in the near of inlet side wall. On the other hands, occurrence of dead zone and eddy flow was confirmed in the opposite side.

• The Korean Journal of Physiology and Pharmacology
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• v.9 no.6
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• pp.353-361
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• 2005

The interaction of cyclosporine A (CsA), an immunosuppressant, with rat brain Kv1.5 (Kv1.5) channels, which were stably expressed in Chinese hamster ovary cells, was investigated using the whole-cell patch-clamp technique. CsA reversibly blocked Kv1.5 currents at +50 mV in a reversible concentrationdependent manner with an apparent $IC_{50}$ of 1.0μM. Other calcineurin inhibitors (cypermethrin, autoinhibitory peptide) had no effect on Kv1.5 and did not prevent the inhibitory effect of CsA. Fast application of CsA led to a rapid and reversible block of Kv1.5, and the onset time constants of the CsA-induced block were decreased in a concentration-dependent manner. The CsA-induced block of Kv1.5 channels was voltage-dependent, with a steep increase over the voltage range of channel opening. However, the block exhibited voltage independence over the voltage range in which channels were fully activated. The rate constants for association and dissociation of CsA were $7.0{\mu}M{-1}s^{-1}$ and $8.1s^{-1}$, respectively. CsA slowed the deactivation time course, resulting in a tail crossover phenomenon. Block of Kv1.5 by CsA was use-dependent. CsA also blocked Kv1.3 currents at +50 mV in a reversible concentration-dependent manner with an apparent $IC_{50}$ of $1.1{\mu}M$. The same effects of CsA on Kv1.3 were also observed in excised inside-out patches when applied to the internal surface of the membrane. The present results suggest that CsA acts directly on Kv1.5 currents as an open-channel blocker, independently of the effects of CsA on calcineurin activity.

• The Korean Journal of Physiology and Pharmacology
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• v.16 no.5
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• pp.343-348
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• 2012

Blocking or regulating $K^+$ channels is important for investigating neuronal functions in mammalian brains, because voltage-dependent $K^+$ channels (Kv channels) play roles to regulate membrane excitabilities for synaptic and somatic processings in neurons. Although a number of toxins and chemicals are useful to change gating properties of Kv channels, specific effects of each toxin on a particular Kv subunit have not been sufficiently demonstrated in neurons yet. In this study, we tested electro-physiologically if heteropodatoxin2 ($HpTX_2$), known as one of Kv4-specific toxins, might be effective on various $K^+$ outward currents in CA1 neurons of organotypic hippocampal slices of rats. Using a nucleated-patch technique and a pre-pulse protocol in voltage-clamp mode, total $K^+$ outward currents recorded in the soma of CA1 neurons were separated into two components, transient and sustained currents. The extracellular application of $HpTX_2$ weakly but significantly reduced transient currents. However, when $HpTX_2$ was added to internal solution, the significant reduction of amplitudes were observed in sustained currents but not in transient currents. This indicates the non-specificity of $HpTX_2$ effects on Kv4 family. Compared with the effect of cytosolic 4-AP to block transient currents, it is possible that cytosolic $HpTX_2$ is pharmacologically specific to sustained currents in CA1 neurons. These results suggest that distinctive actions of $HpTX_2$ inside and outside of neurons are very efficient to selectively reduce specific $K^+$ outward currents.

• Journal of Nutrition and Health
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• v.30 no.10
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• pp.1123-1131
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• 1997

This study examined the effect of dietary lipids and guar gum on lipid metabolism in ovariectomized rats. The experimental animals received ovarietomy (OVX). Lipids sources were divided into 3 groups (soybean oil(SB), beef tallow(BT)) and fish oil(FO)) and guar gum was supplemented to each lipid diet (SBG, BTG, FOG). Experimental diets were fed to therats for 16 weeks. Serum triglyceride (TG) levels were higher in the BT group and lower in the FO group as compared to the SB group .Serum total cholesterol (Tc) and HDL-C levels were lower in the FO group as compared to the SB group. Serum LDL-C and phospholipid levels were lower in the FO group as compared to the SB group. Serum lipids levels were lowered by guar gum supplement. Serum SFA(saturated fatty acids) contents were not significantly influenced by dietary lipids and guar gum. Serum MUFA(monounsaturated fatty acids) contents were the lowest in the SB group. Fecal weight was highest in the beef tallow group and lowest in the fish oil group. Fecal weight was increased by guar gum supplement in all lipid groups. Total bile acid content in feces was increased by guar gum supplement in the soybean oil and beef tallow groups. The endothelial cells of the beef tallow group changed from a flat shape to distorted round and enlarged shapes. The subendothelial layer was the thickness the thickest in the beef tallow group ; the interspace between elastic lamina was widened and elastic lamina was straightened and partly disrupted . The fish oil group showed more porminient endothelial cells and subendothelial layer. Internal elastic membrane and elastic lamina exhibited regularly wavy shapes. Guar gum supplement showed positive effects in all lipids groups. Based on the above results , it is suggested that beef tallow increased serum TG levels and injured the wall of the aorta. On the other hand, fish oil , which decreased serum lipid levels, has a positive effect on the walls of the aorta. Guar gum protects the aorta from injury by reducing the serum lipid levels. Therefore, it is suggested that soybean oil and beef tallow consumed with guar gum is beneficial.

• Journal of Haehwa Medicine
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• v.20 no.1
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• pp.11-23
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• 2011

Systemic Lupus Erythematosus(SLE) is an autoimmune disease invading the skin, joint, kidney, intestinal membrane, neurosystem and other organs. SLE is an autoimmune disease characterized by immune dysregulation resulting in the production of antinuclear antibodies(ANA), generation of circulating immune complexes, and activation of the complement system. In Korean medicine, lupus can be classified as acute arthritis, reddish butterfly erythema, asthenic disease, edema and so on. The cause and procedure of the diseases are flourishing noxious heat, excessive fire due to deficiency of yin, blood stasis due to stagnation of qi, internal movement of the liver-wind, congenital deficiency, exhausted vital-qi, which are treated by clearing away heat and cooling the blood, nourshing yin and extinguishing fire, treating flatulence and activating blood circulation, nourishing the blood to expel wind, invigorating the liver and kidney, invigorating qi and replenishing the blood. To experimentally examine the influence of Insam-Buja-Tang (Ginseng & Aconiti Extract, IBT) on the outbreak and development of lupus, lupus induce MRL/MpJ-Faslpr lupus-prone mice model was used. As IBT was orally administrated to a lupus model mouse, various tests such as the weight, urine protein, renal function, Lymph cell test of the spleen, Cytokine expression, histopathological analysis of kideny were performed to see the influence on the kidney and whether it work effectively on the immune function. The main purpose of this study is to evaluate the effect of IBT on MRL/MpJ-Faslpr lupus-prone mice model. The effect of IBT on MRL/MpJ-Faslpr lupus-prone mice that can have autoimmune disease similar to SLE in human was evaluated after IBT per oral in the present study.

• Journal of fish pathology
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• v.9 no.1
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• pp.33-40
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• 1996

A filamentous form of mollicute-like bacterium was detected during a routine health survey of wild adult kuruma shrimp Penaeus japonicus. The kuruma shrimp were native to Japan and were imported to Korea. The histology showed no pathological changes. Transmission electron microscopy revealed extensive infections of hepatopancreatic epithelial cell by a pleomorphic, filamentous intracellular bacterium. The filamentous bacterium was of about 60 nm in diameter and 300 nm to more than $1{\mu}m$ in length. Teh morphology of bacteria were filamentous and branched with terminal blebs, or knobs, on the branches. They lacked the cell wall, and were bounded by the plasma membrane. They contained typical prokaryotic ribosomes and fibrillar DNA-like strands. No additional internal structure has been observed. They are considered to be mollicutes, based upon the morphological appearance and upon the cellular location.

• KIEAE Journal
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• v.5 no.2
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• pp.11-18
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• 2005

The Purpose of this study is development and analysis of Effluence Characteristic of the Rainfall in the IRMA Green Roof System(developed in KICT) Plus 50 program is an internal research project at KICT(Korean Institute of Construction Technology) which has it as an object ; to lengthen the building's life 50-year or more and reduce energy conception 50% than present. Green roof system is one of the most important theme in the Plus 50 program. Generally, a Green Roof System has a positive effect on the thermal conductivity in winter, the micro cooling effect on building and city by evaporation in summer, the flood-control effect by runoff-reduction or the treated rainwater-quality of green roof system and so on. However, inspection of the physical effect of green roof system does not consider in Korea. Above all, long-term monitoring and a whole observation of green roof system is needed to probate the effect. So a new experimental method could be tried in this research, which is never attempted in Korea. The measurement by a bucket with a great volume, 1L, gives a new dimension of measuring green roof effect to measure the permanent running flood from a wide roof. This offers a reasonable result on a long-term measuring of a running water. Additionally, the thermal behavior of the IRMA(Insulated Roof Membrane Assembly), known in the western europe as a reasonable solution at green roof system by economical benefits and easy construction, would be experimented.