• Title/Summary/Keyword: species barrier

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Transepithelial Migration of Neutrophils in Response to Leukotriene $B_4$ is Mediated by a Reactive Oxygen Species-ERK-linked Cascade

  • Woo, Chang-Hoon;Kim, Jae-Hong
    • Proceedings of the PSK Conference
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    • 2003.04a
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    • pp.103-106
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    • 2003
  • The epithelial cells that form a barrier lining the lung airway are key regulators of neutrophil trafficking into the airway lumen in a variety of lung inflammatory diseases. Although the lipid mediator leukotriene B$_4$ (LTB$_4$) is known to be a principal chemoattractant for recruiting neutrophils to inflamed sites across the airway epithelium, the precise signaling mechanism involved remains largely unknown. (omitted)

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Community Structures of Macrozoobenthos in the Subtidal Area of the Nakdong River estuary, Korea (낙동강 하구 조하대 대형저서동물의 군집구조)

  • SEO, JIN-YOUNG;KIM, JEONG-HYUN;CHOI, JIN-WOO
    • The Sea:JOURNAL OF THE KOREAN SOCIETY OF OCEANOGRAPHY
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    • v.21 no.3
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    • pp.112-124
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    • 2016
  • In order to see the spatio-temporal distribution patterns of macrobenthic fauna in subtidal areas of Nakdong River estuary, benthic fauna samples were collected seasonally at 8 sites in subtidal areas of Nakdong River estuary from February, 2013 to November, 2015. Sandy sediment facies was found in the southern part of the barrier islands in Nakdong River estuary while muddy sediment facies occupied at sites in offshore areas. The bottom salinity of the study area was measured greater than 30 psu during the study period. The mean species richness and density were estimated as 266 species and $859ind\;m^{-2}$, respectively. Polychaete worms were the most abundant fauna group, and four polychaete species such as Goniada maculata, Sternaspis chinensis, Magelona japonica, and Heteromastus filiformis occurred as dominant species in this study area. Pseudopolydora kempi known as an opportunistic species occurred dominantly only in August, 2013. From the multivariate analyses, the macrobenthic fauna in the subtidal area of the Nakdong River estuary could be divided into 2 assemblages that each occupied sites near barrier islands and offshore areas by sediment facies.

Measurement of excited species in discharges using Laser Absorption spectroscopy

  • Sakai, Yosuke
    • Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
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    • 2000.07a
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    • pp.5-8
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    • 2000
  • The population density of excited species in dc, rf and laser ablation plume plasmas has been measured using laser absorption spectroscopy. It was shown that, when the plasma was modulated by on and off with, the sensitivity and signal to noise (S/N) ratio became high. For example, the atomic O(3$^{5}$ S$^{o}$ $_2$) Population density, No* in $O_2$/He mixtures was obtained by the highest S/N ratio at a frequency of 2.7kHz. In a 20Torr room air, the lowest No* level to be detectable was shown to be an order of 10$^{7}$ cm$^{-3}$ . The population densities of resonance Ar(1S$_2$) and Xe(1S$_4$) levels were also measured in barrier discharges and laser ablation plasmas.

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COVID-19 and veterinarians for one health, zoonotic- and reverse-zoonotic transmissions

  • Yoo, Han Sang;Yoo, Dongwan
    • Journal of Veterinary Science
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    • v.21 no.3
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    • pp.51.1-51.5
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    • 2020
  • A novel coronavirus emerged in human populations and spread rapidly to cause the global coronavirus disease 2019 pandemic. Although the origin of the associated virus (severe acute respiratory syndrome coronavirus 2 [SARS-CoV-2]) remains unclear, genetic evidence suggests that bats are a reservoir host of the virus, and pangolins are a probable intermediate. SARS-CoV-2 has crossed the species barrier to infect humans and other animal species, and infected humans can facilitate reverse-zoonotic transmission to animals. Considering the rapidly changing interconnections among people, animals, and ecosystems, traditional roles of veterinarians should evolve to include transdisciplinary roles.

Effect of Halophyte (Spartina anglica and Calystegia soldanella) Extracts on Skin Moisturizing and Barrier Function in HaCaT Cells (염생식물인 갯끈풀과 갯메꽃 추출물의 HaCaT 세포에서 피부 보습 및 피부 장벽 기능에 미치는 영향)

  • Ha, Yuna;Jeong, JaeWoo;Lee, Won Hwi;Oh, Jun Hyuk;Kim, Youn-Jung
    • Journal of Marine Life Science
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    • v.6 no.2
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    • pp.58-65
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    • 2021
  • As aging progresses, reactive oxygen species (ROS) reduces skin moisturization and collapses skin barrier function. In this study, we evaluated the efficacy of skin moisturizing and skin barrier function enhancement by extracts from halophytes using HaCaT cells. Spartina anglica (S. anglica; SAE) and Calystegia soldanella (C. soldanella; CSE), a kind of halophytes, were collected from Dongmak beach in Incheon, and extracted with 70% ethanol. At the first, we evaluated the cytotoxicity of extracts in HaCaT cell using WST-8 Kit. As a result, the other experiment was conducted by setting the concentration at which the cell viability was 90% or more. SAE and CSE showed high radical scavenging activity through ABTS assay. Expression levels of genes related to skin moisturizing and skin barrier functions, were analyzed by real-time qPCR. As a result, it showed that the expression of aquaporin 3, hyaluronan synthase 2, and transglutaminase 1 was increased by SAE treatment but not changed by CSE. Activation of extracellular signal regulated kinase (ERK), c-Jun N-terminal kinase (JNK), and p38 mitogen activated protein kinase was induced by SAE. These results suggest that SAE can be used as functional materials for cosmetics for skin moisturizing and barrier function enhancement.

A Study for Oxidants Generation on Oxygen-plasma Discharging Process Discharging System (산소-플라즈마 공정에서 산화제의 생성에 대한 연구)

  • Kim, Dong-Seog;Park, Young-Seek
    • Journal of Environmental Science International
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    • v.22 no.12
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    • pp.1561-1569
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    • 2013
  • This study carried out a laboratory scale plasma reactor about the characteristics of chemically oxidative species (${\cdot}OH$, $H_2O_2$ and $O_3$) produced in dielectric barrier discharge plasma. It was studied the influence of various parameters such as gas type, $1^{st}$ voltage, oxygen flow rate, electric conductivity and pH of solution for the generation of the oxidant. $H_2O_2$ and $O_3$.) $H_2O_2$ and $O_3$ was measured by direct assay using absorption spectrophotometry. OH radical was measured indirectly by measuring the degradation of the RNO (N-Dimethyl-4-nitrosoaniline, indicator of the generation of OH radical). The experimental results showed that the effect of influent gases on RNO degradation was ranked in the following order: oxygen > air >> argon. The optimum $1^{st}$ voltage for RNO degradation were 90 V. As the increased of $1^{st}$ voltage, generated $H_2O_2$ and $O_3$ concentration were increased. The intensity of the UV light emitted from oxygen-plasma discharge was lower than that of the sun light. The generated hydrogen peroxide concentration and ozone concentration was not high. Therefore it is suggested that the main mechanism of oxidation of the oxygen-plasma process is OH radical. The conductivity of the solution did not affected the generation of oxidative species. The higher pH, the lower $H_2O_2$ and $O_3$ generation were observed. However, RNO degradation was not varied with the change of the solution pH.

A Study of Atmospheric-pressure Dielectric Barrier Discharge (DBD) Volume Plasma Jet Generation According to the Flow Rate (유량에 따른 대기압 유전체 전위장벽방전(DBD) 플라즈마 젯 발생에 관한 연구)

  • Byeong-Ho Jeong
    • Journal of Industrial Convergence
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    • v.21 no.7
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    • pp.83-92
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    • 2023
  • The bullet shape of the plasma jet using the atmospheric-pressure dielectric barrier discharge method changes depending on the applied fluid rate and the intensity of the electric field. This changes appear as a difference in spectral distribution due to a difference in density of the DBD plasma jet. It is an important factor in utilizing the plasma device that difference between the occurrence of active species and the intensity through the analysis of the spectrum of the generated plasma jet. In this paper, a plasma jet generator of the atmospheric pressure volume DBD method using Ar gas was make a prototype in accordance with the proposed design method. The characteristics jet fluid rate analysis of Ar gas was accomplished through simulation to determine the dependence of flow rate for the generation of plasma jets, and the characteristics of plasma jets using spectrometers were analyzed in the prototype system to generate optimal plasma jet bullet shapes through MFC flow control. Through the design method of the proposed system, the method of establishing the optimal plasma jet characteristics in the device and the results of active species on the EOS were verified.

Prions and Prion Diseases: Fundamentals and Mechanistic Details

  • Ryou, Chong-Suk
    • Journal of Microbiology and Biotechnology
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    • v.17 no.7
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    • pp.1059-1070
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    • 2007
  • Prion diseases, often called transmissible spongiform encephalopathies (TSEs), are infectious diseases that accompany neurological dysfunctions in many mammalian hosts. Prion diseases include Creutzfeldt-Jakob disease (CJD) in humans, bovine spongiform encephalopathy (BSE, "mad cow disease") in cattle, scrapie in sheep, and chronic wasting disease (CWD) in deer and elks. The cause of these fatal diseases is a proteinaceous pathogen termed prion that lacks functional nucleic acids. As demonstrated in the BSE outbreak and its transmission to humans, the onset of disease is not limited to a certain species but can be transmissible from one host species to another. Such a striking nature of prions has generated huge concerns in public health and attracted serious attention in the scientific communities. To date, the potential transmission of prions to humans via foodborne infection and iatrogenic routes has not been alleviated. Rather, the possible transmission of human to human or cervids to human aggravates the terrifying situation across the globe. In this review, basic features about prion diseases including clinical and pathological characteristics, etiology, and transmission of diseases are described. Based on recently accumulated evidences, the molecular and biochemical aspects of prions, with an emphasis on the molecular interactions involved in prion conversion that is critical during prion replication and pathogenesis, are also addressed.

Study on the Generation of Chemically Active Species using Air-plasma Discharging System (공기-플라즈마 방전 시스템에서 화학적 활성종의 생성에 대한 연구)

  • Kim, DongSeog;Park, YoungSeek
    • Journal of Korean Society on Water Environment
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    • v.28 no.3
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    • pp.401-408
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    • 2012
  • High-voltage dielectric discharges are an emerging technique in environmental pollutant degradation, which that are characterized by the production of hydroxyl radicals as the primary degradation species. The initiation and propagation of the electrical discharges depends on several physical, chemical, and electrical parameters such as 1st and 2nd voltage of power, gas supply, conductivity and pH. These parameters also influence the physical and chemical characteristics of the discharges, including the production of reactive species such as OH, $H_2O_2$ and $O_3$. The experimental results showed that the optimum 1st voltage and air flow rate for RNO (N-Dimethyl-4-nitrosoaniline, indicator of the generation of OH radical) degradation were 160 V (2nd voltage of is 15 kV) and 4 L/min, respectively. As the increased of the 2nd voltage (4 kV to 15 kV), RNO degradation, $H_2O_2$ and $O_3$ generation were increased. The conductivity of the solution was not influencing the RNO degradation and $H_2O_2$ and $O_3$ generation. The effects pH was not high on RNO degradation. However, the lower pH and the conductivity, the higher $H_2O_2$ and $O_3$ generation were observed.

A Study on the Microorganism Disinfection and Characteristics of Discharged Water of Dielectric Barrier Discharge Plasma Systems (유전체 장벽 방전 플라즈마 방전수의 특성과 미생물 소독에 관한 연구)

  • Kim, Dong-Seog;Park, Young-Seek
    • Journal of Environmental Health Sciences
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    • v.38 no.2
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    • pp.159-165
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    • 2012
  • Objectives: This experiment was carried out to elucidate the effect of discharged water on the disinfection of $Phytophthora$ $capsici$ and evaluate the water characteristics. Methods: The dielectric barrier discharges (DBD) plasma reactor system used in this study consisted of a plasma component [discharge, ground electrode and quartz dielectric tube], high voltage source, and air supply. The effects of water characteristics such as pH, ORP and conductivity and the disinfection effect of discharged water were investigated. Results: Experimental results showed that in the process of discharge, the pH decreased, whereas ORP and electric conductivity increased. When the discharge time was 30 min, $Phytophthora$ $capsici$ of 2.94 log was disinfected within 300 seconds. Disinfection performance of stored discharged water was maintained for three days; however the disinfection effect vanished after five days. When $Phytophthora$ $capsici$ was injected into the discharged water, the disinfection effect decreased after two days. Conclusions: It is considered that the main disinfection parameters of the discharged water were chemically active species such as $H_2O_2$ and $O_3$ and high ORP.