• Title/Summary/Keyword: Barrier factor

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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.

Study on Effect of Skin Soothing by Helianthus annuus (Sunflower) Seed Oil (Helianthus annuus (Sunflower) Seed Oil 의 항염 및 피부 개선 효과 연구)

  • Jimin So;Gaewon Nam
    • Journal of the Society of Cosmetic Scientists of Korea
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    • v.49 no.4
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    • pp.331-339
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    • 2023
  • In this study, in vitro and clinical studies were conducted to assess the anti-inflammatory effects and skin improvement effects, including moisturizing, sebum secretion-regulating, skin barrier function enhancing, and soothing of Helianthus annuus (Sunflower) seed oil. In in vitro study using cultured human epidermal keratinocytes induced with inflammation by lipopolysaccharide, significant decreases in inflammatory cytokines interleukin-6, interleukin-8, and tumor necrosis factor alpha was revealed, indicating the anti-inflammatory effects of H. annuus (Sunflower) seed oil. Additionally, the results of clinical study on subjects with sensitive skin demonstrated improved skin hydration, regulation of sebum secretion, enhanced skin barrier function, as well as amelioration of skin redness and acne, indicating positive effects on overall skin conditions after application of H. annuus (Sunflower) seed oil containing test product for 4 weeks. Results of this study demonstrated the potential of H. annuus (Sunflower) seed oil as an ingredient for cosmetic, targeting consumers with sensitive skin.

Landform Changes of Terminal Area of the Nagdong River Delta, Korea (낙동강 삼각주 말단의 지형 변화)

  • 오건환
    • The Korean Journal of Quaternary Research
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    • v.13 no.1
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    • pp.67-78
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    • 1999
  • In present, the terminal area of the Nagdong River Delta consists of micro-depositional landforms with sand barrier islands, sand bars and tidal flats which are arranged parallel to the present shoreline, and have rapidly shifted toward sea during last 100 years due to human activities such as construction of estuary dam, industrial complex and residential area. To clarify the landform changes of the area, the author traced the morphologic change pattern based on interpretation of air-photos, topographic maps and old Korean traditional map, and the results are as follows ; Based on the Daedongyeojido, one of the old Korean map, published in 1861, the area including upper part of the delta was underlying by sea level except two larger sand barriers, which means the Nagdong River Delta was not completely formed as the present outline of morphology by 1860s. According to the topographic map(1 :50,000) of 1916, the delta resembled to the present morphology pattern was exposed in 1916, and at this time the area was mainly composed of one sand barrier island, four sand bars and tidal flats, which had slowly elongated southwards before construction of the Nagdong River Estuary Dam in 1987. But after 1987, the area has been rapidly and drastically shifted southwards in arrange with one chain of sand barrier islands (Elsugdo -Myeonghodo-Sinhodo ) and four chains of sand bars (first chain ; Jinwoodo -Daemadeung-Maenggeummeorideung, second chain : Jangjado-Baeghabdeung, third chain ; Saedeung-Namusitdeung, fourth : Doyodeung-Dadaedeung) parallel to shoreline. This rapid landform change of the area is now occurring, and is seemed to ascribed firstly, to the construction of the Nagdong River Estuary Dam on Elsugdo in 1987, the Sinho Industrial Complex on Sinhodo and Myeongji Residential Area on Myeonghodo in 1992, secondly, to artificial alteration of drainage channel and consequential breakdown of former energy system between riverflow and tidal-and wave-energy. From these facts, it is inferred that the landform change pattern of the area will continue until a new equilibrium between the factor available to this energy system is accomplished.

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Effect of the Inhibition of PLA2 on Oxidative Lung Injury Induced by $Interleukin-1{\alpha}$

  • Lee, Young-Man;Cho, Hyun-Gug;Park, Yoon-Yub;Kim, Jong-Ki;Lee, Yoon-Jeong;Park, Won-Hark;Kim, Teo-An
    • The Korean Journal of Physiology and Pharmacology
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    • v.2 no.5
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    • pp.617-628
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    • 1998
  • In order to understand the pathogenetic mechanism of adult respiratory distress syndrome (ARDS), the role of phospholipase A2 (PLA2) in association with oxidative stress was investigated in rats. $Interleukin-1{\alpha}\;(IL-1,\;50\;{\mu}g/rat)$ was used to induce acute lung injury by neutrophilic respiratory burst. Five hours after IL-1 insufflation into trachea, microvascular integrity was disrupted, and protein leakage into the alveolar lumen was followed. An infiltration of neutrophils was clearly observed after IL-1 treatment. It was the origin of the generation of oxygen radicals causing oxidative stress in the lung. IL-1 increased tumor necrosis factor (TNF) and cytokine-induced neutrophil chemoattractant (CINC) in the bronchoalveolar lavage fluid, but mepacrine, a PLA2 inhibitor, did not change the levels of these cytokines. Although IL-1 increased PLA2 activity time-dependently, mepacrine inhibited the activity almost completely. Activation of PLA2 elevated leukotriene C4 and B4 (LTC4 and LTB4), and 6-keto-prostaglandin $F2{\alpha}\;(6-keto-PGF2{\alpha})$ was consumed completely by respiratory burst induced by IL-1. Mepacrine did not alter these changes in the contents of lipid mediators. To estimate the functional changes of alveolar barrier during the oxidative stress, quantitative changes of pulmonary surfactant, activity of gamma glutamyltransferase (GGT), and ultrastructural changes were examined. IL-1 increased the level of phospholipid in the bronchoalveolar lavage (BAL) fluid, which seemed to be caused by abnormal, pathological release of lamellar bodies into the alveolar lumen. Mepacrine recovered the amount of surfactant up to control level. IL-1 decreased GGT activity, while mepacrine restored it. In ultrastructural study, when treated with IL-1, marked necroses of endothelial cells and type II pneumocytes were observed, while mepacrine inhibited these pathological changes. In histochemical electron microscopy, increased generation of oxidants was identified around neutrophils and in the cytoplasm of type II pneumocytes. Mepacrine reduced the generation of oxidants in the tissue produced by neutrophilic respiratory burst. In immunoelectron microscopic study, PLA2 was identified in the cytoplasm of the type II pneumocytes after IL-1 treatment, but mepacrine diminished PLA2 particles in the cytoplasm of the type II pneumocyte. Based on these experimental results, it is suggested that PLA2 plays a pivotal role in inducing acute lung injury mediated by IL-1 through the oxidative stress by neutrophils. By causing endothelial damage, functional changes of pulmonary surfactant and alveolar type I pneumocyte, oxidative stress disrupts microvascular integrity and alveolar barrier.

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Rg3-enriched Korean Red Ginseng extract inhibits blood-brain barrier disruption in an animal model of multiple sclerosis by modulating expression of NADPH oxidase 2 and 4

  • Lee, Min Jung;Choi, Jong Hee;Oh, Jinhee;Lee, Young Hyun;In, Jun-Gyo;Chang, Byung-Joon;Nah, Seung-Yeol;Cho, Ik-Hyun
    • Journal of Ginseng Research
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    • v.45 no.3
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    • pp.433-441
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    • 2021
  • Background: Multiple sclerosis (MS) and its animal model, the experimental autoimmune encephalomyelitis (EAE), are primarily characterized as dysfunction of the blood-brain barrier (BBB). Ginsenoside-Rg3-enriched Korean Red Ginseng extract (Rg3-KRGE) is known to exert neuroprotective, anti-inflammatory, and anti-oxidative effects on neurological disorders. However, effects of Rg3-KRGE in EAE remain unclear. Methods: Here, we investigated whether Rg3-KRGE may improve the symptoms and pathological features of myelin oligodendroglial glycoprotein (MOG)35-55 peptide - induced chronic EAE mice through improving the integrity of the BBB. Results: Rg3-KRGE decreased EAE score and spinal demyelination. Rg3-KRGE inhibited Evan's blue dye leakage in spinal cord, suppressed increases of adhesion molecule platelet endothelial cell adhesion molecule-1, extracellular matrix proteins fibronection, and matrix metallopeptidase-9, and prevented decreases of tight junction proteins zonula occludens-1, claudin-3, and claudin-5 in spinal cord following EAE induction. Rg3-KRGE repressed increases of proinflammatory transcripts cyclooxygenase-2, inducible nitric oxide synthase, interleukin (IL)-1 beta, IL-6, and tumor necrosis factor-alpha, but enhanced expression levels of anti-inflammatory transcripts arginase-1 and IL-10 in the spinal cord following EAE induction. Rg3-KRGE inhibited the expression of oxidative stress markers (MitoSOX and 4-hydroxynonenal), the enhancement of nicotinamide adenine dinucleotide phosphate (NADPH) oxidase 2 (NOX2) and NOX4, and NADPH activity in the spinal cord of chronic EAE mice. Furthermore, apocynin, a NOX inhibitor, mimicked beneficial effects of Rg3-KRGE in chronic EAE mice. Conclusion: Our findings suggest that Rg3-KRGE might alleviate behavioral symptoms and pathological features of MS by improving BBB integrity through modulation of NOX2/4 expression.

Geological Factor Analysis for Evaluating the Long-term Safety Performance of Natural Barriers in Deep Geological Repository System of High-level Radioactive Waste (지질학적 심지층 처분지 내 천연방벽의 고준위 방사성 폐기물 장기 처분 안전성 평가를 위한 지질학적 인자 분석)

  • Hyeongmok Lee;Jiho Jeong;Jaesung Park;Subi Lee;Suwan So;Jina Jeong
    • Economic and Environmental Geology
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    • v.56 no.5
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    • pp.533-545
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    • 2023
  • In this study, an investigation was conducted on the features, events, and processes (FEP) that could impact the long-term safety of the natural barriers constituting high-level radioactive waste geological repositories. The FEP list was developed utilizing the IFEP list 3.0 provided by the Nuclear Energy Agency (NEA) as foundational data, supplemented by geological investigations and research findings from leading countries in this field. A total of 49 FEPs related to the performance of the natural barrier were identified. For each FEP, detailed definitions, classifications, impacts on long-term safety, significance in domestic conditions, and feasibility of quantification were provided. Moreover, based on the compiled FEP list, three scenarios that could affect the long-term safety of the disposal facility were developed. Geological factors affecting the performance of the natural barrier in each scenario were selected and their relationships were visualized. The constructed FEP list and the visualization of interrelated factors in various scenarios are anticipated to provide essential information for selecting and organizing factors that must be considered in the development of mathematical models for quantitatively evaluating the long-term safety of deep geological repositories. In addition, these findings could be effectively utilized in establishing criteria related to the key performance of natural barriers for the confirmation of repository sites.

New APJCP Impact Factor for 2012 is 1.271 - Time to Make a Major Effort to Break Through the 2.0 Barrier

  • Moore, Malcolm A.;Lim, Min-Kyung;Huang, Xin-En
    • Asian Pacific Journal of Cancer Prevention
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    • v.14 no.6
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    • pp.3377-3378
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    • 2013
  • The APJCP Impact Factor for 2012 is 1.271, returning from 0.659 for 2011 (1.240 for 2010 and 1.108 for 2009). For an Asian Pacific journal publishing over 100 papers a month from countries with very varied resources it is heartening and we thank all those who continued to submit papers and cite references in the APJCP through our difficult period. However, we still have very much room for improvement. As Chief Editors it is our shared responsibility to act for the benefit of the cancer control research community who utilize the journal in our region of over four billion people and provide a prestigious forum for publication of research findings which can be freely shared by all. The motivation for the APOCP/APJCP has never been financial profit but a firm financial base is nevertheless essential. Although we have kind support from the Korean National Cancer Center for our Managing Editor and the website, our ability to maintain our Chinese and Thai offices is totally dependent on the processing charges paid by the authors. In order to expand our staff to cope with increased submissions and provide greater assistance in ensuring comprehensive reference coverage and dissemination of findings published in the APJCP to the worldwide research community, a joint decision has been made to increase formatting charges by 50% from July. We ask for author understanding. In addition, we appeal to scientists to positively consider our requests to make their reference lists as comprehensive as possible, including papers from the APJCP where appropriate. The future of the journal and the APOCP is largely in your own hands.

Tilianin Inhibits MUC5AC Expression Mediated Via Down-Regulation of EGFR-MEK-ERK-Sp1 Signaling Pathway in NCI-H292 Human Airway Cells

  • Song, Won-Yong;Song, Yong-Seok;Ryu, Hyung Won;Oh, Sei-Ryang;Hong, JinTae;Yoon, Do-Young
    • Journal of Microbiology and Biotechnology
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    • v.27 no.1
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    • pp.49-56
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    • 2017
  • In the human airway, mucus exists to protect the respiratory system as a primary barrier of the innate immune system. However, hyperexpressed mucus limits airflow, resulting in a decrease of lung function. Among more than 20 mucin family members, MUC5AC and MUC5B are major glycoproteins in human airway mucus. The epidermal growth factor receptor (EGFR) signaling pathway is one of the mechanisms of these mucins expression and specificity protein-1 (Sp1) transcription factor is the downstream signal of this pathway, playing pivotal roles in mucin expression. Even though there are some drugs for treating mucus hypersecretion, no drug has proven effects on humans. We found that the flavonoid tilianin regulated MUC5AC expression and also inhibited Sp1 phosphorylation. In this study, we investigated how tilianin would modulate EGFR signaling and regulate mucin production. In conclusion, tilianin inhibited MUC5AC expression mediated via modulating the EGFR-MEK-ERK-Sp1 signaling pathway in NCI-H292 human airway epithelial cells. This study may provide the basis for the novel treatment of mucus hypersecretion.

A Study on the Relationship of Skin Surface pH with Nutrient Intake or Dietary Pattern in Healthy Adults (건강한 성인에서 피부 산도와 영양소 섭취 및 식사패턴과의 상관성 연구)

  • Kang, Hye-Jin;Kim, Kun-Pyo;Cho, Yunhi
    • The Korean Journal of Food And Nutrition
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    • v.30 no.1
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    • pp.9-18
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    • 2017
  • As an indicator of skin health, acidified skin surface pH ranging from 5 to 7 is crucial for maintaining skin barrier. In this study, we evaluated the relationship between skin pH and dietary pattern (DP) as well as nutrient or food intake in 48 healthy middle aged adults. Skin pH was measured in the skin surface of the inner arm, and blood lipid profile was analyzed. Dietary intake data were obtained using 1 day 24 hour recall method, and DP was extracted using factor analysis. Results revealed that skin pH ranged from 5.15 to 6.88 in all subjects. There was no significant difference in skin pH between males and females. When subjects were grouped by tertile of skin pH, the food intake of fruit, and the nutrient intake of omega 6 fatty acid, potassium, vitamin A, vitamin C, ${\beta}$-carotene, and riboflavin in the first tertile group with skin pH ranging from 5.15 to 5.68 were significantly higher than in the third tertile group with skin pH ranging from 6.26 to 6.88. There was no difference in blood lipid profile between the first and the third tertile group. Among 5 DP extracted by factor analysis, DP5 characterized by a high intake of nuts and fruits as well as a low intake of beverages and alcohol was inversely correlated with skin pH after adjusting for gender and age. DP5 was positively correlated with nutrient intake of carbohydrate, fiber, potassium, iron, vitamin A, vitamin C, ${\beta}$-carotene, thiamine, and riboflavin but negatively correlated with sodium after adjusting for gender, age, smoking, and energy intake. Therefore, acidified skin pH could be maintained by these DP and nutrients.

A Study on Assessment of Mothers Perception of a Newborn Baby (어머니의 신생아에 대한 지각사정에 관한 연구)

  • 이자형
    • Journal of Korean Academy of Nursing
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    • v.16 no.3
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    • pp.67-77
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    • 1986
  • The research was carried out in order to assess, at an early stage, the potential barrier in mother-child relationship in the childs' development by using the screening tool. Consequently, after modifying the Neonatal Perception Inventory developed by Broussard and testing its reliability. It has been applied to 152 mothers at the hospital of three universities in Seoul from August 1 to September 30, 1986. The data was analyzed by S.P.S.S. pro-gram and the results were as follows: 1) Mothers perceived the newborn as an individual, and evaluated their baby higher than other babies. 2) Mothers indicated difficulties in their role performance in the fellowing order-bathing, safety, detecting pain or suffering, and feeding. 3) Mothers' perception of a newborn was positive for 75% of the mothers. 4) The factor analysis of the modified tool using principal components analysis and Varimax rotation resulted in the two factors: Factor 1, Baby as an individual: Factor Ⅱ, Performances are required to meet the new-born's needs. 5) The difference in mothers' individual characteristics such as the number of childbirth, the desire to get pregnant or not, the type of deli-very, and the sex of the newborn did not influence on a mothers' perception of her newborn. As seen above, most of the mothers perceived their newborns as able individuals and expressed difficulties involved in taking care of the newborn. Also most of the mothers perceived their babies positively. My point here is, we ought to observe those mothers who perceive their babies negatively, and then compare them with those mothers who perceive their babies extremely positive or extremely negative. In the future, for more comprehensive assessment tool for maternal perception of the newborn, a repetitive verification and modification of this tool is demanded. At the same time, father's perception of the newborn should be included.

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