• 제목/요약/키워드: capillary permeability

검색결과 128건 처리시간 0.025초

도심지 강우 특성을 고려한 투수성 보도블록의 배수 특성 (Characteristics of Drainage Pervious Block Considering Urban Rainfall)

  • 서다와;윤태섭;염광수;정상섬;문성호
    • 한국지반공학회논문집
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    • 제31권1호
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    • pp.53-64
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    • 2015
  • 본 연구는 도심지 내 집중 강우 특성을 고려한 투수성 보도블록의 배수 특성을 알아보기 위하여 2 가지 골재크기에 대하여 강도, 투수성, 증발 및 배수실험을 실시하였다. 강도의 경우 골재크기와 무관하게 한국산업표준(KS) 규격을 만족시킨 반면, 작은 골재로 구성된 투수성 보도블록의 경우 단위시간당 유량이 작은 경우에도 표면유출이 발생하였다. 큰 골재는 초기 우수조건에서의 배수는 원활한 반면 일정시간이 지난 후 동일한 유량의 배수실험에서 표면유출이 관찰되었다. 이는 간극 내부의 물이 투수성을 저감시키는 역할로 작용한 것으로, 투수성 보도블록의 투수성과 배수 성능은 간극비나 간극연결도 만으로 결정되는 것이 아니고 시간에 따른 증발, 선행우수조건에 의해 좌우됨을 나타낸다. 또한 초기 포화도보다는 이중선형 형태의 시간당 증발 양상과 유입량과 증발로 인한 내부 포화도 변화가 표면유출에 미치는 영향이 큰 것으로 나타났다.

Analgesic and anti-inflammatory effects of galangin: a potential pathway to inhibit transient receptor potential vanilloid 1 receptor activation

  • Kaiwen Lin;Datian Fu;Zhongtao Wang;Xueer Zhang;Canyang Zhu
    • The Korean Journal of Pain
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    • 제37권2호
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    • pp.151-163
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    • 2024
  • Background: Galangin, commonly employed in traditional Chinese medicine for its diverse medicinal properties, exhibits potential in treating inflammatory pain. Nevertheless, its mechanism of action remains unclear. Methods: Mice were randomly divided into 4 groups for 7 days: a normal control group, a galangin-treated (25 and 50 mg/kg), and a positive control celecoxib (20 mg/kg). Analgesic and anti-inflammatory effects were evaluated using a hot plate test, acetic acid-induced writhing test, acetic acid-induced vascular permeability test, formalin-induced paw licking test, and carrageenan-induced paw swelling test. The interplay between galangin, transient receptor potential vanilloid 1 (TRPV1), NF-κB, COX-2, and TNF-α proteins was evaluated via molecular docking. COX-2, PGE2, IL-1β, IL-6, and TNF-α levels in serum were measured using ELISA after capsaicin administration (200 nmol/L). TRPV1 expression in the dorsal root ganglion was analyzed by Western blot. The quantities of substance P (SP) and calcitonin gene-related peptide (CGRP) were assessed using qPCR. Results: Galangin reduced hot plate-induced licking latency, acetic acid-induced contortions, carrageenan-triggered foot inflammation, and capillary permeability in mice. It exhibited favorable affinity towards TRPV1, NF-κB, COX-2, and TNF-α, resulting in decreased levels of COX-2, PGE2, IL-1β, IL-6, and TNF-α in serum following capsaicin stimulation. Galangin effectively suppressed the upregulation of TRPV1 protein and associated receptor neuropeptides CGRP and SP mRNA, while concurrently inhibiting the expression of NF-κB, TNF-α, COX-2, and PGE2 mRNA. Conclusions: Galangin exerts its anti-inflammatory pain effects by inhibiting TRPV1 activation and regulating COX-2, NF-κB/TNF-α expression, providing evidence for the use of galangin in the management of inflammatory pain.

Anti-Allergic and Anti-Asthmatic Activity of Helioscopinin-A, a Polyphenol Compound, Isolated from Euphorbia helioscopia

  • Park, Kwan-Ha;Koh, Dong-Soo;Lee, Seung-Ho;Jung, Ill-Min;Kim, Kyung-Hyun;Lee, Chul-Hoon;Kim, Kye-Hoon;Lim, Yoong-Ho
    • Journal of Microbiology and Biotechnology
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    • 제11권1호
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    • pp.138-142
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    • 2001
  • During the course of searching for anti-allergic substances from unexplored plant sources, an inhibitor of leukotriene $D_4$-induced tracheal contraction was isolated from Euphoribia helioscopia. This isolated polyphenol compound, known as helioscopinin-A, showed a certain inhibitory activity on capillary permeability in passive cutaneous anaphylaxis responses of rats and also on antigen-induced bronchial constriction in an experimental asthma model of guinea pigs. The compound at a high concentration weakly inhibited histamine release from isolated mast cells of rats. It is suggested that this compound is an anti-allergic and anti-asthmatic which exerts its activity through antagonism on leukotrene $D_4$-induced responses. A partial inhibition of allergic mediator relase may also bee involved.

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Anti-arthritic Effect of Glucosamine and Oriental Herbal Composition

  • ;;;;김영권
    • 대한의생명과학회지
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    • 제14권2호
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    • pp.97-103
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    • 2008
  • This study was conducted to investigate the effect of an anti-inflammatory and analgesic action of the glucosamine HCl (Glucosamine) and SH-1 (Glucosamine + Oriental herbal composition combined group). Male sprague-Dawley rats $(200{\sim}250g)$ and ICR mice $(20{\sim}30g)$ were randomized and these experimental groups were divided into 4 groups. Two control group were given as negative control (saline) and positive control (Ibuprofen, 100 mg/kg) and two groups given as oral administration of Glucosamine (320 m/kg) and SH-1. Carrageenan induced paw edema test, hot plate method, croton oil induced granuloma, capillary permeability test and acetic acid writhing syndrome were also shown to be comparable in the SH-1 group to anti-inflammatory drug group such as positive control group (Ibuprofen). Although further studies should be performed to confirm the effects of SH-1, present results suggest that the combined administration of SH-1 have potential action in anti-inflammatory and analgesic action. It could be applicable for the improvement of arthritic symptoms as a new diet-supplement.

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Graves병 안구증에서 $^{99m}Tc-DTPA$ 뇌신티그라피를 이용한 안구/뇌 방사능비에 관한 연구 (The Eye/Brain Radioactivity Ratio for Assessment of Graves' Ophthalmopathy)

  • 이범우;성상규;박원;서관식;최덕주;김종순
    • 대한핵의학회지
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    • 제22권1호
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    • pp.27-31
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    • 1988
  • In Graves' disease, changes in orbital tissue and structure are casued by inflammatory infiltation, which induces increase of capillary permeability and breakdown of blood-tissue barriers. Using the uptake of $^{99m}Tc-DTPA$ in inflammatory lesion, Eye/Brain radioactivity ratios in brain scintigraphy were evaluated in 15 normal controls and 40 Graves' patients. The results were as follows; 1) Eye/Brain radioactivity ratio was significantly higher in Graves' ophthalmopthy group than in control group (p < 0.005). 2) In Graves' ophthalmopathy, Eye/Brain radioactivity ratio was significantly higher in active (progressive) group than in inactive (non-progressive) group (p < 0.05). 3) There was no correlation between class of ATA classification of Graves' ophthalmopathy and Eye/Brain radioactivity ratio. 4) There was no correlation between Eye/Brain radioactivity ratio and serum activity of TBII. In conclusion, Eye/Brain radioactivity ratio using $^{99m}Tc-DTPA$ brain scintigraphy may be useful to determine the activity of Graves' ophthalmopathy and whether treatment of Graves' ophthalmopathy is necessary or not.

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Durability of self compacted concrete containing slag in hot climate

  • Yahiaoui, Walid;Kenai, Said;Menadi, Belkacem;Kadri, El-Hadj
    • Advances in concrete construction
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    • 제5권3호
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    • pp.271-288
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    • 2017
  • This paper aims to investigate the effects of replacing cement with ground granulated blast furnace slag (GGBFS) in self compacting concrete in the fresh and hardened state. The performance of SCC in moderate climate is well investigated but few studies are available on the effect of hot environment. In this paper, the effect of initial water-curing period and curing conditions on the performance of SCC is reported. Cement was substituted by GGBFS by weight at two different levels of substitution (15% and 25%). Concrete specimens were stored either in a standard environment (T=$20^{\circ}C$, RH=100%) or in the open air in North Africa during the summer period (T=35 to $40^{\circ}C$; R.H=50 to 60%) after an initial humid curing period of 0, 3, 7 or 28 days. Compressive strength at 28 and 90 days, capillary absorption, sorptivity, water permeability, porosity and chloride ion penetration were investigated. The results show that the viscosity and yield stress are decreased with increasing dosage of GGBFS. The importance of humid curing in hot climates in particular when GGBFS is used is also proved. The substitution of cement by GGBFS improves SCC durability at long term. The best performances were observed in concrete specimens with 25% GGBFS and for 28 days water curing.

화장품용 천연계면활성제의 제조 및 이용 최신기술 (Manufacturing and Application of Natural Surfactants for Cosmetics)

  • 김형원
    • 접착 및 계면
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    • 제14권4호
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    • pp.197-211
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    • 2013
  • 계면활성제는 상간의 경계면 활성화를 통한 표면장력의 강하능력을 가져 모든 세제(detergents)와 화장품(cosmetics)에 사용되는 필수 주원료이다. 합성세제란 석유화학계의 EO (ethylene oxide), LAB (linear alkylbenzene) 등의 합성계면활성제로 제조한 제품으로 이는 난분해성으로 지구환경, 특히 하천과 강물오염의 주범으로 생태계파괴의 원인이 되고 있다. 이는 또한 분자가 작아 침투력이 강해 피부를 자극하여 아토피피부염을 유발하고 모세관을 통해 기관으로 들어가면 암을 유발할 수도 있다. 최근 합성계면활성제를 대체할 수 있는 양친매성의 생분해성 친환경 및 무자극의 다기능성물질로서 천연 계면활성제 또는 생합성의 생물 계면활성제(biosurfactants)의 개발에 국제적인 관심이 고조되고 있다.

Waste Isolation Pilot Plant Performance Assessment: Radionuclide Release Sensitivity to Diminished Brine and Gas Flows to/from Transuranic Waste Disposal Areas

  • Day, Brad A.;Camphouse, R.C.;Zeitler, Todd R.
    • Nuclear Engineering and Technology
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    • 제49권2호
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    • pp.450-457
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    • 2017
  • Waste Isolation Pilot Plant repository releases are evaluated through the application of modified parameters to simulate accelerated creep closure, include capillary pressure effects on relative permeability, and increase brine and gas saturation in the operations and experimental (OPS/EXP) areas. The modifications to the repository model result in increased pressures and decreased brine saturations in waste areas and increased pressures and brine saturations in the OPS/EXP areas. Brine flows up the borehole during a hypothetical drilling intrusion are nearly identical and brine flows up the shaft are decreased. The modified parameters essentially halt the flow of gas from the southern waste areas to the northern nonwaste areas, except as transported through the marker beds and anhydrite layers. The combination of slightly increased waste region pressures and very slightly decreased brine saturations result in a modest increase in spallings and no significant effect on direct brine releases, with total releases from the Culebra and cutting and caving releases unaffected. Overall, the effects on total high-probability mean releases from the repository are insignificant, with total low-probability mean releases minimally increased. It is concluded that the modified OPS/EXP area parameters have an insignificant effect on the prediction of total releases.

In vitro Alternatives to Skin Irritation Test

  • Shin, Dae-Sup;Kim, Dai-Byung;Ryu, Seung-Rel;Lee, Sun-Hee;Koh, Jae-Sook;Park, Won-Sae;Kim, Pu-Young
    • Biomolecules & Therapeutics
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    • 제3권3호
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    • pp.242-244
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    • 1995
  • In vitro cell culture system has been proposed as a promising alternative model to in vivo skin irritation test. These studies were performed to screen the cytotoxicity effects of surfactants using normal human skin fibroblasts. Cell membrane integrity assessed by the leakage of lactate dehydrogenase (LDH) and mitochondrial integrity by MTT [3-(4, 5-dimethylthiazol-2-yl)-2, 5-diphenyl tetrazolium bromides reduction test were affected in a dose dependent manner. The irritation potential of surfactants to human skin patch test, and the changes of capillary permeability by rabbit intradermal safety test were assessed as in vivo methods. Our results suggest that LDH leakage assay and MTT reduction test using cultured human fibroblasts could be predictive for the irritancy of various surfactants in human, and LDH assay is superior correlated with in vivo test (r=0.886) to MTT test with in vivotest (r=0.757).

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불포화 토양에서 공기의 배출/제한이 침투속도에 미치는 영향 (Effects of Air Drain and Confined Conditions to Infiltration Rate in Unsaturated Soils)

  • 김상래;기재홍;김영진;한무영
    • 상하수도학회지
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    • 제22권6호
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    • pp.681-687
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    • 2008
  • It is well known that the water infiltration rate depends on soil properties such as soil water content, water head, capillary suction, density, hydraulic conductivity, and porosity. However, most of proposed infiltration models assume that the air phase is continuous and in equilibrium with the atmosphere or air compression and air entrapment on infiltration was not considered. This study presents experimental results on unsaturated water infiltration to relate air entrapment and hydraulic conductivity function based on soil air properties. The objectives of this study were to measure change of soil air pressure ahead of wetting front under air drain and air confined condition to find the confined air effect on infiltration rate, to reduce the entrapped air volume related with soil air pressure to increase the soil permeability, and to make a basis of infiltration process model for the purpose of improvement of infiltration rate in the homogeneous soil column. The results of the work show that soil air pressure increases according to increasement of the saturated soil depth rather than the wetting front depth during infiltration process.