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231.
Lee KH Chow YL Sharmili V Abas F Alitheen NB Shaari K Israf DA Lajis NH Syahida A 《International journal of molecular sciences》2012,13(3):2985-3008
Our preliminary screening has shown that curcumin derivative BDMC33 [2,6-bis(2,5-dimethoxybenzylidene)cyclohexanone] exerted promising nitric oxide inhibitory activity in activated macrophages. However, the molecular basis and mechanism for its pharmacological action is yet to be elucidated. The aim of this study was to investigate the anti-inflammatory properties of BDMC33 and elucidate its underlying mechanism action in macrophage cells. Our current study demonstrated that BDMC33 inhibits the secretion of major pro-inflammatory mediators in stimulated macrophages, and includes NO, TNF-α and IL-1β through interference in both nuclear factor kappaB (NF-κB) and mitogen activator protein kinase (MAPK) signaling cascade in IFN-γ/LPS-stimulated macrophages. Moreover, BDMC33 also interrupted LPS signaling through inhibiting the surface expression of CD-14 accessory molecules. In addition, the inhibitory action of BDMC33 not only restricted the macrophages cell (RAW264.7), but also inhibited the secretion of NO and TNF-α in IFN-γ/LPS-challenged microglial cells (BV-2). The experimental data suggests the inflammatory action of BDMC33 on activated macrophage-like cellular systems, which could be used as a future therapeutic agent in the management of chronic inflammatory diseases. 相似文献
232.
Moisture adsorption isotherms of spray-dried yogurt powder were determined at 10, 25, and 40°C using the standard, static-gravimetric method. Experimental data were fitted to five mathematical models (Guggenheim-Anderson-de Boer [GAB], Brunauer-Emmett-Teller [BET], Halsey, modified Oswin, and modified Henderson). A nonlinear regression analysis method was used to evaluate the constants of the sorption equations. The shelf-life of yogurt powder was predicted based on the relationship between permeability coefficient of the packaging material and moisture adsorbed by the powder determined by the GAB equation. Furthermore, the storage stability of spray-dried yogurt powder in terms of quality parameters including moisture content, water activity, color change, and thiobarbituric acid (TBA) value was studied in aluminum laminated polyethylene (ALPE) pouches under storage conditions of 25°C and 50% relative humidity (RH). 相似文献
233.
Color combination criteria are said to entail an affective response in interior design. We investigated the color combination criteria that orient the preference of current observers, after Le Corbusier's 1931 Salubra keyboards. We explored the similarity/contrast in Natural Color System (NCS) hue, blackness, and chromaticness in 312 combinations with four colors, two backgrounds and two accent colors, coming from 43 individual colors, on the walls of a simulated interior of a bedroom from the Swiss Pavilion (Le Corbusier, 1930-1931). Participants were 644 students of architecture and interior design in Western Europe and Near East, who evaluated with a Likert scale their preference for virtual images via an online survey. Results indicate that the most preferred color combinations are those with hues closer in the color wheel, being the similarity between hues in the backgrounds more important than in the accent colors, and with NCS B30G to G as the most preferred hues. Observers preferred color compositions with blackness under 10% and similar blackness between the two background colors, together with a certain blackness contrast between these background colors and the two color accents. Similarly, observers liked color compositions with low chromaticness and low chromaticness difference among the four colors of the composition. 相似文献
234.
Organo clay modified alkyd resins were prepared and these modified alkyd resins were cured with different ratios of melamine formaldehyde and urea formaldehyde resins in this work. Alkyds formulated to have oil content 40% were prepared with phthalic anhydride (PA), glycerine (G), coconut oil fatty acid (COFA), dipropylene glycol (DPG) and organo clay. “K alkyd constant system” was used for the formulation calculations of the alkyd resins. Alkyd resins were blended with 40% of a commercial melamine formaldehyde. The films of the alkyd–amino resins were prepared from 60% solid content xylene solutions using 50 μm applicators. After the films were cured at 140 °C for 2 h in an oven, properties of the films were determined. The film properties of the alkyd–amino resins such as drying degree, hardness, adhesion strength, abrasion resistance, water, acid, alkaline, solvent resistance, and resistance to environmental conditions were investigated. The addition of the urea formaldehyde resin and organo clay has positive effect on the physical and chemical resistance of the alkyd–amino resins. 相似文献
235.
Single fiber fragmentation test (SFFT) was used to investigate the interfacial adhesion in glass fiber‐unsaturated polyester composites. A simplified approach was developed for SFFT based on determination of the maximum number of fragments on the fiber at the end of the test. This approach does not involve length measurements and shortens the experiment time to a few minutes. By using a digital camera attached to the microscope, photographs of the coupon were taken during the test, and the number of fragments within the gauge length were counted later. This method allows quick, quantitative comparison of different fibers and matrices. The test samples were prepared by using commercial polyester resin and E‐glass fibers having different commercial sizings. SFFT results were in excellent agreement with the macromechanical test done on samples prepared with the same glass fiber and same polyester. The crack modes and debonding phenomena were examined from the microscopic images. Atomic force microscopic (AFM) images of the fiber were examined to get detailed topographic information about fiber surfaces. To improve interfacial adhesion, commercial unsaturated polyester was reacted with 3‐aminopropyltriethoxy silane via Michael Addition reaction on the maleate double bonds of the polyester. The resulting silylated polyester was characterized by H1 NMR spectroscopy. The results of SFFT showed that the maximum numbers of fragments increased 23% on using silylated polyester. © 2009 Wiley Periodicals, Inc. J Appl Polym Sci, 2010 相似文献
236.
The C-terminal domain of Nipah virus (NiV) nucleocapsid protein (NP401–532) was inserted at the N-terminus and the immunodominant loop of hepatitis B core antigen (HBc). The stability of NP401–532 increased tremendously when displayed on the HBc particles. These particles reacted specifically with the swine anti-NiV and the human anti-HBc antisera. 相似文献
237.
Mert Dalaran Serkan Emik Gamze Güçlü Tülin Banu İyim Saadet Özgümüş 《Polymer Bulletin》2009,63(2):159-171
In this study, poly(DMAEMA–AMPS–HEMA) terpolymer/montmorillonite nanocomposite hydrogels were prepared by in situ polymerization
technique using 2-(N,N-dimethylamino)ethyl methacrylate (DMAEMA), 2-acrylamido-2-methlypropane sulfonic acid (AMPS), 2-hydroxyethyl methacrylate
(HEMA) monomers in clay suspension media. N,N-methylenebisacrylamide (NMBA) was used as crosslinker and potassium persulfate/potassium bisulfide were used as initiator
and accelerator pair. The water absorption capacities and acidic dye (indigo carmine) adsorption properties of the nanocomposite
hydrogels were investigated. Adsorption properties of the hydrogels were investigated at different conditions such as different
initial dye concentration and contact time. The concentrations of the dyes were determined using UV/Vis Spectrophotometer
at wavelength 610 nm. Langmuir and Freundlich isotherm models were used to describe adsorption data and the results clarified
that these models were the best-fit for the adsorption of indigo carmine. 相似文献
238.
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240.
The identification of semantic relations from a raw text is an important problem in Natural Language Processing. This paper provides semi-automatic pattern-based extraction of part–whole relations. We utilized and adopted some lexico-syntactic patterns to disclose meronymy relation from a Turkish corpus. We applied two different approaches to prepare patterns; one is based on pre-defined patterns that are taken from the literature, second automatically produces patterns by means of bootstrapping method. While pre-defined patterns are directly applied to corpus, other patterns need to be discovered first by taking manually prepared unambiguous seeds. Then, word pairs are extracted by their occurrence in those patterns. In addition, we used statistical selection on global data that is obtaining from all results of entire patterns. It is a whole-by-part matrix on which several association metrics such as information gain, T-score, etc., are applied. We examined how all these approaches improve the system accuracy especially within corpus-based approach and distributional feature of words. Finally, we conducted a variety of experiments with a comparison analysis and showed advantage and disadvantage of the approaches with promising results. 相似文献