• Title/Summary/Keyword: Smoke extraction

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Upregulation of Heme Oxygenase-1 as an Adaptive Mechanism against Acrolein in RAW 264.7 Macrophages

  • Lee, Nam-Ju;Lee, Seung-Eun;Park, Cheung-Seog;Ahn, Hyun-Jong;Ahn, Kyu-Jeung;Park, Yong-Seek
    • Molecular & Cellular Toxicology
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    • v.5 no.3
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    • pp.230-236
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    • 2009
  • Acrolein, a known toxin in cigarette smoke, is the most abundant electrophilic $\alpha$, $\beta$-unsaturated aldehyde to which humans are exposed in a variety of environmental pollutants, and is also product of lipid peroxidation. Increased unsaturated aldehyde levels and reduced antioxidant status plays a major role in the pathogenesis of various diseases such as diabetes, Alzheimer's and atherosclerosis. The findings reported here show that low concentrations of acrolein induce heme oxygenase-1 (HO-1) expression in RAW 264.7 macrophages. HO-1 induction by acrolein and signal pathways was measured using reverse transcription-polymerase chain reaction, Western blot and immunofluorescence staining analyses. Inhibition of extracellular signal-regulated kinase activity significantly attenuated the induction of HO-1 protein by acrolein, while suppression of Jun N-terminal kinase and p38 activity did not affect induction of HO-1 expression. Moreover, rottlerin, an inhibitor of protein kinase $\delta$, suppressed the upregulation of HO-1 protein production, possibly involving the interaction of NF-E2-related factor 2 (Nrf2), which has a key role as a HO-1 transcription factor. Acrolein elevated the nuclear translocation of Nrf2 in nuclear extraction. The results suggest that RAW 264.7 may protect against acrolein-mediated cellular damage via the upregulation of HO-1, which is an adaptive response to oxidative stress.

A Study on the Refractory Performance Verification of the Thermal Insulators for AES Ducts and Piping (AES 계열 덕트·배관 단열재의 내화성능 검증에 관한 연구)

  • Kwang-Ho Ham;Jea-Chun Sa;Joo-Hwan Lee;Se-Hong Min
    • Journal of the Society of Disaster Information
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    • v.20 no.2
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    • pp.419-429
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    • 2024
  • Purpose: To enhance the non-combustibility of fire protection piping insulation and improve the heat resistance of smoke extraction duct insulation, I plan to verify the suitability of AES insulation materials for these applications through performance testing. Method: The non-combustibility, heat resistance, and thermal insulation performance of AES insulation materials will be verified through various tests. Result: According to the 'Standards for Flame Retardancy and Fire Spread Prevention of Building Finishing Materials,' the results of non-combustibility and gas toxicity tests confirmed the non-combustible properties. The standard fire resistance tests verified the fire resistance performance. Additionally, the thermal insulation performance was confirmed through building insulation tests. Conclusion: As the performance tests on AES inorganic insulation materials have proven their noncombustibility, fire resistance, and thermal insulation performance, these materials are considered a viable alternative for improving fire spread prevention in buildings.

Image Registration and Fusion between Passive Millimeter Wave Images and Visual Images (수동형 멀리미터파 영상과 가시 영상과의 정합 및 융합에 관한 연구)

  • Lee, Hyoung;Lee, Dong-Su;Yeom, Seok-Won;Son, Jung-Young;Guschin, Vladmir P.;Kim, Shin-Hwan
    • The Journal of Korean Institute of Communications and Information Sciences
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    • v.36 no.6C
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    • pp.349-354
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    • 2011
  • Passive millimeter wave imaging has the capability of detecting concealed objects under clothing. Also, passive millimeter imaging can obtain interpretable images under low visibility conditions like rain, fog, smoke, and dust. However, the image quality is often degraded due to low spatial resolution, low signal level, and low temperature resolution. This paper addresses image registration and fusion between passive millimeter images and visual images. The goal of this study is to combine and visualize two different types of information together: human subject's identity and concealed objects. The image registration process is composed of body boundary detection and an affine transform maximizing cross-correlation coefficients of two edge images. The image fusion process comprises three stages: discrete wavelet transform for image decomposition, a fusion rule for merging the coefficients, and the inverse transform for image synthesis. In the experiments, various types of metallic and non-metallic objects such as a knife, gel or liquid type beauty aids and a phone are detected by passive millimeter wave imaging. The registration and fusion process can visualize the meaningful information from two different types of sensors.