• The Korean Journal of Physiology and Pharmacology
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• v.3 no.4
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• pp.405-414
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• 1999

The role of platelet-activating factor (PAF) was investigated in intestinal ischemia/reperfusion (I/R) induced acute lung injury associated with oxidative stress. To induce acute lung injury following intestinal I/R, superior mesenteric arteries were clamped with bulldog clamp for 60 min prior to the 120 min reperfusion in Sprague-Dawley rats. Acute lung injury by intestinal I/R was confirmed by the measurement of lung leak index and protein content in bronchoalveolar lavage (BAL) fluid. Lung leak and protein content in BAL fluid were increased after intestinal I/R, but decreased by WEB 2086, the PAF receptor antagonist. Furthermore, the pulmonary accumulation of neutrophils was evaluated by the measurement of lung myeloperoxidase (MPO) activity and the number of neutrophils in the BAL fluid. Lung MPO activity and the number of neutrophils were increased (p＜0.001) by intestinal I/R and decreased by WEB 2086 significantly. To confirm the oxidative stress induced by neutrophilic respiratory burst, gamma glutamyl transferase (GGT) activity was measured. Lung GGT activity was significantly elevated after intestinal I/R (p<0.001) but decreased to the control level by WEB 2086. On the basis of these experimental results, phospholipase $A_2\;(PLA_2),$ lysoPAF acetyltransferase activity and PAF contents were measured to verify whether PAF is the causative humoral factor to cause neutrophilic chemotaxis and oxidative stress in the lung following intestinal I/R. Intestinal I/R greatly elevated $PLA_2$ activity in the lung as well as intestine (p<0.001), whereas WEB 2086 decreased $PLA_2$ activity significantly (p<0.001) in both organs. LysoPAF acetyltransferase activity, the PAF remodelling enzyme, in the lung and intestine was increased significantly (p<0.05) also by intestinal I/R. Accordingly, the productions of PAF in the lung and intestine were increased (p<0.001) after intestinal I/R compared with sham rats. The level of PAF in plasma was also increased (p<0.05) following intestinal I/R. In cytochemical electron microscopy, the generation of hydrogen peroxide was increased after intestinal I/R in the lung and intestine, but decreased by treatment of WEB 2086 in the lung as well as intestine. Collectively, these experimental results indicate that PAF is the humoral mediator to cause acute inflammatory lung injury induced by intestinal I/R.

• Journal of Korean Society of Environmental Engineers
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• v.32 no.1
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• pp.79-86
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• 2010

Effects of operating parameters such as applied voltage, solution conductivity, ferrous ion concentration, electrode material on phenol degradation by pulsed corona discharges were investigated in laboratory scale experiments. The increase of applied voltage enhanced the phenol degradation by generating more energetic electrons. The solution conductivity inversely affected phenol removal rate in the tested ranges because the increase of conductivity decreased the electric field strength through the liquid phase. The addition of ferrous sulfate promoted the phenol degradation through the OH radical production by the Fentonlike reactions between ferrous ion and hydrogen peroxide generated by pulsed corona discharges. Catechol and hydroquinone were detected as primary intermediates of phenol degradation and the decrease of pH and the increase of conductivity were observed probably due to the generation of organic acids. Almost all of the initial phenol was disappeared and 29% of total organic corbon (TOC) was removed in the condition of 0.5 mM of ferrous sulfate after approximately 230 kJ of discharge energy transferred to the reactor.

• Journal of Environmental Science International
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• v.18 no.3
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• pp.299-308
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• 2009

We manufactured PVA-derived hydrogels using a foam generation technique that has been widely used to prepare colloidal gas aphrons(CGA). These gels were differentiated to the conventional gels such as for medical or pharmaceutical applications, which have tiny pores and some crystalline structure. Rather these should be used in de-pollution devices or adhesion of cells or biomolecules. The crosslinkers used in this work were amino acid, organic acid, sugars and lipids(vitamins). The structures of the gels were observed in a scanned electron microscope. Amino acids gels showed remarkably higher swelling ratios probably because their typical functional groups help constructing a highly crosslinked network along with hydrogen bonds. Boric acid and starch would catalyze dehydration while structuring to result in much lower water content and accordingly high gel content, leading to less elastic, hard gels. Bulky materials such as ascorbic acid or starch produced, in general, large pores in the matrices and also nicotinamide, having large hydrophobic patches was likely to enlarge pore size of its gels as well since the hydrophobicity would expel water molecules, thus leading to reduced swelling. Hydrophilicity(or hydrophobicity), functional groups which are involved in the reaction or physical linkage, and bulkiness of crosslinkers were found to be more critical to gel's cross linking structure and its density than molecular weights that seemed to be closely related to pore sizes. Microscopic observation revealed that pores were more or less homogeneous and their average sizes were $20{\mu}m$ for methionine, $10-15{\mu}m$ for citric acid, $50-70{\mu}m$ for L-ascorbic acid, $30-40{\mu}m$ for nicotinamide, and $70-80{\mu}m$ for starch. Also a sensory test showed that amino acid and glucose gels were more elastic meanwhile acid and nicotinamide gels turned out to be brittle or non-elastic at their high concentrations. The elasticity of a gel was reasonably correlated with its water content or swelling ratio. In addition, the PVA gel including 20% ascorbic acid showed fair ability of cell adherence as 0.257mg/g-hydrogel and completely degraded phenanthrene(10 mM) in 240 h.

• Korean Journal of Fisheries and Aquatic Sciences
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• v.20 no.5
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• pp.419-430
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• 1987

The damage of plasmid DNA by lipid peroxidation and its inhibition were investigated through the model system of DNA and linoleic acid at $37^{\circ}C$. The degree of DNA damage increased in proportion to the increase of concentration and peroxidation of linoleic acid. DNA damage induced from linoleic acid peroxidation was greatly inhibited by the addition of active oxygen scavengers, especially, singlet of oxygen scavenge$(\alpha-tocopherol,\;cysteine)$ and superoxide anion scavenger(superoxide dismutase, ascorbic acid) in reaction system. These active oxygens, such as superoxide anion and hydrogen peroxide were rapidly generated in the early stage of peroxidation (POV below 100 mg/kg) and also scanvenged by the addition of superoxide dismutase and catalase, respectively. Hydroperoxide isolated from autoxidised linoleic acid showed DNA damage. Hydroperoxide induced-DNA damage was not inhibited by active oxygen scavengers. Lipid oxidation products, malonaldehyde and hexanal, also influenced on the DNA damage. Accordingly, it is speculated that DNA damage by lipid oxidation products is due to active oxygens such as singlet oxygen and superoxide anion formed in the early stage of peroxidation, direct action of hydroperoxide and formation of low molecular carbonyl compound-DNA complex. Furthermore, DNA damage induced by lipid peroxidation was remarkably inhibited by the addition of active oxygen scavengers and natural antioxidative fractions extracted from garlic and ginger. These antioxidative fractions also suppressed the generation of active orygens and linoleic acid oxidation. It is assumed that the inhibition of DNA damage by garlic and ginger extracts is due to the scavenging effect of active oxygens and the inhibition of hydroperoxide and oxidation products formation.

• Journal of the Microelectronics and Packaging Society
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• v.25 no.3
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• pp.1-5
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• 2018

In this study, the effects of indium (In) doping in InGaN/GaN multi quantum well (MQW) on photoelectrochemical (PEC) properties were investigated. Each quantum well (QW) layer with controlled In content were grown on sapphire substrate. Before growth of MQW, GaN growth consisted of various stages in the following order: buffer GaN growth, undoped GaN growth, and Si-doped n-type GaN growth. Absorbance of InGaN/GaN MQW having different In composition was higher than that of the InGaN/GaN MQW having a constant In composition. It indicates that InGaN layer having different In composition absorbs light having a broad spectrum energy. These results are in agreement with those in photoluminescence (PL). After evaluation of PEC properties, it demonstrated that InGaN/GaN MQW having different In composition was improved InGaN/GaN MQW having constant In composition in PEC water splitting ability.

• The Journal of Art Theory & Practice
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• no.13
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• pp.35-71
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• 2012

The purpose of this essay is to examine the responses of artists on nuclear experiences through an analysis of the nuclear images represented in contemporary Japanese art. Japan has previously as twice experienced nuclear disaster in 20th century. The first atomic bombs were dropped in 1945 as well as the 5th Fukuryumaru, Japanese pelagic fishing boat, exposed by hydrogen bomb test operated by the US in 1954 nearby Bikini atoll. Due to Tsunami taken place by the great earthquake that caused the meltdown of Fukushima Nuclear Power Plant in March 2010, Japan is being experienced a nuclear disaster again. Despite practical experiences, comtemporary Japanese art has avoided the subject of nuclear disasters since the end of the Asia-Pacific War for a variety of reasons. Firstly, GHQ prohibited to record or depict the terrible effect of atomic bomb until 1946. Secondly, Japanese government has tried to sweep the affair under the carpet quite a while a fact of nuclear damage to their people. Because Japan has produced numerous war record paintings during the Second World War, in the aftermath of the defeated war, most of Japanese artists thought that dealing with politics, economics, and social subject was irrelevant to art as well as style of amateur in order to erase their melancholic memory on it. In addition, silence that was intended to inhibit victims of nuclear disasters from being provoked psychologically has continued the oblivion on nuclear disasters. For these reasons, to speak on nuclear bombs has been a kind of taboo in Japan. However, shortly after the atomic bomb dropped on Hiroshima, the artist couple Iri and Toshi Maruki visited to ruin site as a volunteer for Victim Relief. They portrayed the horrible scenes of the legacy of nuclear bomb since 1950 based on their observation. Under the condition of rapid economical growth in 1960s and 1970s, Japanese subculture such as comics, TV animations, plastic model, and games produced a variety of post apocalyptic images recalling the war between the USA and Japanese militarism, and battle simulation based on nuclear energy. While having grown up watching subculture emerged as Japan Neo-Pop in 1990s, New generation appreciate atomic images such as mushroom cloud which symbolizes atomic bomb of Hiroshima. Takashi Murakami and other Neo-Pop artists appropriate mushroom cloud image in their work. Murakami curated three exhibitions including and persists in superflat and infantilism as an evidence in order to analyze contemporary Japanese society. However, his concept, which is based on atomic bomb radiation exposure experience only claimed on damage and sacrifice, does not reflect Japan as the harmer. Japan has been constructing nuclear power plants since 1954 in the same year when the 5th Fukuryumaru has exposed until the meltdown of Fukushima Nuclear Plant although took place of nuclear radiation exposures of Three Mile and Chernobyl. Due to the exploding of Fukushima Nuclear Power Plant, Japan reconsiders the danger of nuclear disaster. In conclusion, the purpose of this paper may be found that the sense of victim which flowed in contemporary art is able to inquire into the response of artist on the subject of nuclear as well as the relationship between society, politics, culture, and modern history of Japan and international political situation.

• Proceedings of the Korean Society for Emotion and Sensibility Conference
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• 2000.11a
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• pp.105-112
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• 2000

The conventional model did not take momentum conservation into consideration when the electron absorbs and emits the photons. II-ray provides momentum conservations on any directions of the entering photons, and also the electrons have radial momentum conservations and fully elastic bouncing between two atoms, in the new atom model. Conventional atom model must be criticized on the following four points. (1) Natural motions between positive and negative entities are not circular motions but linear going and returning ones, fur examples sexual motion, tidal motion, day and night etc. Because the radius of hydrogen atom's electron orbit is the order of 10$^{-11}$ m and the radia of the nucleons in the nucleus are the order of 10$^{-l4}$m and then the converging $\pi$-gamma rays to the nucleus have so great circular momentum, the electron can not have a circular motion. We can say without doubt that any elementary mass particle can have only linear motion, because of the $\pi$-rays' hindrances, near the nucleus. (2) Potential energy generation was neglected when electron changes its orbit from outer one to inner one. The h v is the kinetic energy of the photo-electron. The total energy difference between orbits comprises kinetic and potential energies. (3) The structure of the space must be taken into consideration because the properties of the electron do not change during the transition from outer orbit to inner one even though it produces photon. (4) Total energy conservation law applies to the energy flow between mind and matter because we daily experiences a interconnection between mind and body. Any magnet absorbs n-rays to S pole and sends out the $\pi$-rays from N pole. Proton are constructed with the closed n-rays quantum-mechanically. The crystallizing n-bonding makes two $\pi$-far infrared rays of one wave length between two protons if two $\pi$-rays are supplied to each proton. It is easily done for a $\pi$-ray to be absorbed to a proton if there is a parallel magnetic flow to the blood flow because a $\pi$-ray advances axially under a magnetic field and a proton looks like a sphere. A axially advancing disk-like $\pi$-ray can meet more easily the coming spheres than from the other directions. The blood crystals stimulate the autonomous nerves on the blood vessels during the flow by their mechanical sliding collisions. SM n-ray meridian therapy and SMACN $\pi$-ray meridian therapy show the stimulation of blood flow and also combinational experiment between SM $\pi$-ray meridian therapy and n-ray psycho-physics acupuncture shows more clearly that magnet is forcing to make $\pi$-rays absorbed to the nucleons.s.ons.

• Proceedings of the Korean Society for Emotion and Sensibility Conference
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• 2000.11a
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• pp.98-104
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• 2000

The conventional model did not take momentum conservation into consideration when the electron absorbs and emits the photons. II-ray provides momentum conservations on any directions of the entering photons, and also the electrons have radial momentum conservations and fully elastic bouncing between two atoms, in the new atom model. Conventional atom model must be criticized on the following four points. (1) Natural motions between positive and negative entities are not circular motions but linear going and returning ones, for examples sexual motion, tidal motion, day and night etc. Because the radius of hydrogen atom's electron orbit is the order of 10$^{-11}$ m and the radia of the nucleons in the nucleus are the order of 10$^{-14}$ m and then the converging $\pi$-gamma rays to the nucleus have so great circular momentum, the electron can not have a circular motion. We can say without doubt that any elementary mass particle can have only linear motion, because of the $\pi$-rays'hindrances, nearthenucleus. (2) Potential energy generation was neglected when electron changes its orbit from outer one to inner one. The h v is the kinetic energy of the photo-electron. The total energy difference between orbits comprises kinetic and potential energies. (3) The structure of the space must be taken into consideration because the properties of the electron do not change during the transition from outer orbit to inner one even though it produces photon. (4) Total energy conservation law applies to the energy flow between mind and matter because we daily experiences a interconnection between mind and body. Conventional Concept of Electric Field must be extended in the case of the direct and alternating current. Conventional concept is based on coulomb's force while the electric potential in the direct and alternating current is from Gibb's free energy. And also conventional concept has not any consciousness with human being but the latters has a conscious sensibility. The cell emf is from the kinetic energy of the open $\pi$-rays flow through the conducting wire. The electric potential in alternating current is from that the trans-orbital moving of the induced change of magnetic field in the wire produces flows of open $\pi$-rays, which push the rotating electrons on the orbital and then make the current flow. Human consciousness can induce a resonance with the sensibility of the open $\pi$-rays in the electric measuring equipment. Specially treated acupunctures with Nasucon is for sending an acupunctural effect from one place to another via space by someone's will power.

• The Korean Journal of Food And Nutrition
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• v.33 no.2
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• pp.215-221
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• 2020

The purpose of this study was to investigate the protective effect on oxidative stress induced PC12 cells, and volatile flavor composition of essential oils derived from medicinal plant seeds- Gossypium hirsutum L. (G. hirsutum), Coix lachryma-jobi (C. lachryma-jobi) and Oenothera biennis (O. biennis). The essential oils were obtained by the solvent (hexane) extraction method from the seeds. The essential oils of the seeds were analyzed by the solid-phase micro-extraction gas chromatography mass spectrometry (SPME-GC/MS). The major compounds of G. hirsutum, C. lachryma-jobi and O. biennis were cyclonexanol (16.65%), β-asarone (14.29%) and ylangene (50.01%). The DPPH radical scavenging activity (IC₅₀) was the highest value of 8.52 mg/mL in the O. biennis. Additionally, IC₅₀ values of G. hirsutum and C. lachryma-jobi were 26.76 mg/mL and 36.81 mg/mL. For the oxidative stress on PC12 cells, we treated with hydrogen peroxide (H₂O₂). The pretreatment of oxidative stress induced PC12 cells with all the essential oils preserved or increased their cell viability and G. hirsutum and O. biennis attenuated the ROS generation (by 68.75% and 56.25% vs. H₂O₂ control). The results of this study suggest that the essential oils derived from medicinal plant seeds could be used as valuable back data as a natural essential oil material to prevent neurodegenerative diseases by protecting neuro-cells.

• Proceedings of the Korean Vacuum Society Conference
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• 2012.02a
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• pp.434-435
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• 2012

Plasma enhanced chemical vapor deposition (PECVD) silicon dioxide thin films have many applications in semiconductor manufacturing such as inter-level dielectric and gate dielectric metal oxide semiconductor field effect transistors (MOSFETs). Fundamental chemical reaction for the formation of SiO2 includes SiH4 and O2, but mixture of SiH4 and N2O is preferable because of lower hydrogen concentration in the deposited film [1]. It is also known that binding energy of N-N is higher than that of N-O, so the particle generation by molecular reaction can be reduced by reducing reactive nitrogen during the deposition process. However, nitrous oxide (N2O) gives rise to nitric oxide (NO) on reaction with oxygen atoms, which in turn reacts with ozone. NO became a greenhouse gas which is naturally occurred regulating of stratospheric ozone. In fact, it takes global warming effect about 300 times higher than carbon dioxide (CO2). Industries regard that N2O is inevitable for their device fabrication; however, it is worthwhile to develop a marginable nitrous oxide free process for university lab classes considering educational and environmental purpose. In this paper, we developed environmental friendly and material cost efficient SiO2 deposition process by substituting N2O with O2 targeting university hands-on laboratory course. Experiment was performed by two level statistical design of experiment (DOE) with three process parameters including RF power, susceptor temperature, and oxygen gas flow. Responses of interests to optimize the process were deposition rate, film uniformity, surface roughness, and electrical dielectric property. We observed some power like particle formation on wafer in some experiment, and we postulate that the thermal and electrical energy to dissociate gas molecule was relatively lower than other runs. However, we were able to find a marginable process region with less than 3% uniformity requirement in our process optimization goal. Surface roughness measured by atomic force microscopy (AFM) presented some evidence of the agglomeration of silane related particles, and the result was still satisfactory for the purpose of this research. This newly developed SiO2 deposition process is currently under verification with repeated experimental run on 4 inches wafer, and it will be adopted to Semiconductor Material and Process course offered in the Department of Electronic Engineering at Myongji University from spring semester in 2012.