• Title/Summary/Keyword: harmful factor

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Effect of the corrosion of plate with double cracks in bonded composite repair

  • Berrahou, Mohamed;Salem, Mokadem;Mechab, B.;Bouiadjra, B. Bachir
    • Structural Engineering and Mechanics
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    • v.64 no.3
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    • pp.323-328
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    • 2017
  • This paper presents a three-dimensional finite element method analysis of repairing plate with bonded composite patch subjected to tensile load. The effect of the corrosion on the damage of the adhesive (FM73) in the length of two horizontal cracks on the both sides is presented. The obtained results show that the crack on the left side creates a very extensive area of the damaged zone and gives values of the stress intensity factor (SIF) higher than that on the right side. We can conclude that the left crack is more harmful (dangerous) than that on the right side.

When Methane is decomposed on the CRT Manufacturing Process

  • Lee, Byoung-Joo;Hong, Sang-Pyo;Ko, Byoung-Doo;Hwang, Cheol-Ho
    • 한국정보디스플레이학회:학술대회논문집
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    • 2002.08a
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    • pp.1051-1052
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    • 2002
  • Vacuum surroundings in Cathode Ray Tubes (CRT) are very important factor for CRT lifetime, especially cathode & getter's. A getter is a very good vacuum pump; unfortunately, it cannot absorb an inert gas and hydrocarbons. There are only argon and helium in CRT after $1^{st}$ emission test because other active gases are absorbed by getter and methane is decomposed during CRT working. It is also very important to know exactly where and when methane is decomposed during the CRT manufacturing process, because methane is known to be harmful to cathode when its amount is high, and getter can't absorb the methane.

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Strengthening of Veterinary Services for Safety and Quality Control of the Livestock Products as Food in the Market Internationalization Era (국제관방화 시대에 있어서 축산식품의 안전성 및 품질에 대한 수의학적 관리강화 방안)

  • 박근식;박종명;조준형
    • Korean Journal of Poultry Science
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    • v.18 no.2
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    • pp.121-135
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    • 1991
  • Facing the international open-trade of agricultural and livestock products, a basic strategy is urgently necessary to improve the domestic livestock industry to an international level. Price and quality competitions are the most important target in international trade. Improvement in productivity of livestock is the most important factor in price competition. In recent trade of livestock products, quality competition becomes more important than price competition in livestock products, and will be severer in the future. Basic strategies for higher productivity and safety of livestock products are listed as follows : 1. Protection from exotic diseases 2. Eradication of indigenous diseases 3. Development of new methods and techniques for control of animal diseases 4. Application of hygiene and management techniques 5. Safety evaluation of feedstuffs and animal drugs, and 6. Development of technique and regulations for prevention and monitoring of residue of harmful chemicals.

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Reevaluation of the Generation of Reactive Oxygen Species (ROS) by Cochlodinium polykrikoides as a Fish Killing Factor; Comparison with Chattonellla marina

  • Kim, Dae-Kyung;Oda, Tatsuya;Muramatsu, Tsuyoshi;Honjo, Tsuneo
    • Proceedings of the Korean Society of Fisheries Technology Conference
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    • 2001.10a
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    • pp.206-207
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    • 2001
  • Cochlodinium polykrikoides is one of the most harmful red tide dinoflagellates and is highly toxic to fish. Red tides due to this dinoflagellate have been reported in Korea, Japan, and other countries, and frequently cause severe damage to fish farming. Recently study has suggested that C. polykrikoides generates reactive oxygen species (ROS) such as superoxide anion ($O_{2-}$) and hydrogen peroxide ($H_2O_2$), and the ROS-mediated ichthyotoxicity has been proposed. (omitted)

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A Study on the Fire Safety Performance of Interior Surface Materials in a Building (건축물의 실내건축 재료에 관한 화재안전성 연구)

  • Seo, Su-Eun;Shin, Seung-Woo
    • Proceedings of the Safety Management and Science Conference
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    • 2013.11a
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    • pp.275-290
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    • 2013
  • The main cause of building fire fatalities occur in the combustible material heat, smoke and toxic gases are. Building interior decoration, etc., especially as much of the harmful substances generated during combustion, and, used in domestic architecture wallpaper, ceiling, and other plastics, built-in foam insulation also analyzed recognition of fire hazards approach to test the conkalrorimiteo test, choedaeyeolbangchulryul through, chongbal heat, mass loss rate, generates carbon monoxide gas hazard ratio tests, analysis and evaluation rigid foam index testing the toxicity of hazardous material generated by performing a gas clean up and assess the material test results, the minimum order to provide data to quantify the risk of fire. Ensure fire safety of building materials, composite materials in order to test the various risk factors could be considered organic to the introduction of testing and evaluation is needed urgently.

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A Study on Ulraviolet-cut Ability of Silk Fabric Dyed with Natural Dyestuffs (천연염재의 자외선 차단성능 연구)

  • 김월순;최인려
    • The Research Journal of the Costume Culture
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    • v.12 no.1
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    • pp.1-11
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    • 2004
  • This study was carried out on the process of natural dye substances which can flock ultraviolet rays without producing harmful substances by pollution, germs, etc. While making human body safe in contact, extracting Gardenia, Sappan wood, Radix scutellariae, Cromwell, Mugwort, Gallnut, Lac. Those are used for curing diseases, dyeing silk cloth with those extracts, and examining the color fastness, Ultraviolet protection. From this study, the following conclusion was produced. Brightness was lower in pre-mordanting than in post. And color difference showed that Radix scutellariae was the highest. Aluminum-mordanting showed a higher color difference than Fe. Colorfastness to washing was high in all samples, and the degree of color-changing by washing was the highest in the sample dyed by gardenia, pre-mordanted gallnut showed the highest degree. Colorfastness to perspiration was the highest in gardenia. UV-A test showed that all samples a high rate of 85% or higher compared with test white cloth. Especially, post-mordanted radix scutellariae, pre-mordanted gallnut and post-mordanted sappanwood showed a superior blocking rate.

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Isolation of Lactobacillus plantarum from Kimchi and Its Inhibitory Activity on the Adherence and Growth of Helicobacter pylori

  • Lee, Hak-Mee;Lee, Yeon-Hee
    • Journal of Microbiology and Biotechnology
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    • v.16 no.10
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    • pp.1513-1517
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    • 2006
  • One single lactic acid producing bacterium, isolated from kimchi, inhibited the growth and adherence of Helicobacter pylori to the human gastric epithelial cell line MKN-45. This isolate was identified as Lactobacillus plantarum and termed L. plantarum strain PL9011. The adherence of H pylori, in the presence of live or nonviable L. plantarum strain PL9011 (10-fold CFU), decreased to 14-20%. The spent culture supernatant of L. plantarum strain PL9011 resulted in the eradication of H pylori. This activity remained stable following neutralization and heat treatment, but not following pepsin treatment, thereby suggesting small peptides as the inhibitory factor. L. plantarum strain PL9011 did not produce any harmful metabolites or enzymes. The results obtained in this study suggest that the L. plantarum strain PL9011 may be a potential novel probiotic for the stomach.

Senotherapeutics and Their Molecular Mechanism for Improving Aging

  • Park, Jooho;Shin, Dong Wook
    • Biomolecules & Therapeutics
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    • v.30 no.6
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    • pp.490-500
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    • 2022
  • Aging is defined as physiological dysfunction of the body and a key risk factor for human diseases. During the aging process, cellular senescence occurs in response to various extrinsic and intrinsic factors such as radiation-induced DNA damage, the activation of oncogenes, and oxidative stress. These senescent cells accumulate in many tissues and exhibit diverse phenotypes, such as resistance to apoptosis, production of senescence-associated secretory phenotype, cellular flattening, and cellular hypertrophy. They also induce abnormal dysfunction of the microenvironment and damage neighboring cells, eventually causing harmful effects in the development of various chronic diseases such as diabetes, cancer, and neurodegenerative diseases. Thus, pharmacological interventions targeting senescent cells, called senotherapeutics, have been extensively studied. These senotherapeutics provide a novel strategy for extending the health span and improving age-related diseases. In this review, we discuss the current progress in understanding the molecular mechanisms of senotherapeutics and provide insights for developing senotherapeutics.

Salty taste: the paradoxical taste

  • In-Sun, Choi;Kyung-Nyun, Kim
    • International Journal of Oral Biology
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    • v.47 no.4
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    • pp.49-54
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    • 2022
  • Taste is a basic sensation to get attracted toward nutritious foods or avoid possible harmful substances. The basic taste qualities in humans consist of sweet, bitter, umami, salty, and sour. Basically, sweet and umami tastes make food attractive, whereas bitter and sour tastes make it avoidable. Salty taste comprises basic salty and high salt taste. The basic salty taste is known as amiloride-sensitive salty taste, which is inhibited by amiloride, but the high salt taste is not sensitive to amiloride. Moreover, high salt taste can also cause avoidance behavior in human beings. Sodium, one of the most important cations in the body fluids of vertebrates, controls the volume of total body fluids and is a risk factor for cardiovascular diseases, such as hypertension. The concentration of sodium in body fluids must be under delicate control. A distinction between the salty taste and high salt taste would be a contributing mechanism to control the volume and/or osmolarity of body fluids.

Formaldehyde Deodorization Effect and Far-Infrared Emission Characteristics of Ceramics Prepared with Sawdust, Risk Husk, and Charcoal: Effect of Material Mixing Ratio

  • HWANG, Jung-Woo;OH, Seung-Won
    • Journal of the Korean Wood Science and Technology
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    • v.50 no.2
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    • pp.104-112
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    • 2022
  • Indoor air quality is a very important environmental factor in modern society. However, air pollutants generated from various interior construction materials significantly affect the human body, including formaldehyde (HCHO) and volatile organic compounds that threaten public health by deteriorating indoor air quality. Effective in removing these harmful substances are porous materials, such as woodceramics. In this study, charcoal, a porous material, was added to rice husk, an agricultural by-product, and sawdust generated during the sawing process to prepare boards and ceramics at different mixing ratios, and the HCHO deodorization performance and far-infrared emission characteristics were measured. As the mixing ratio of charcoal increased, the deodorization rate of the boards and ceramics tended to increase. Overall, the deodorization rate was measured to be 80% to 90%, indicating that the boards and ceramics prepared with charcoal are suitable to be used for the purpose of deodorization. The effect of the material mixing ratio on far-infrared emissivity and emission power was insignificant.