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Menglu Yang Nora Botten Robin Hodges Jeffrey Bair Tor P. Utheim Charles N. Serhan Darlene A. Dartt 《International journal of molecular sciences》2022,23(1)
Resolvin (Rv) D2 and RvD1 are biosynthesized from docosahexaenoic acid (DHA) and promote resolution of inflammation in multiple organs and tissues, including the conjunctiva. Histamine is a mediator produced by mast cells in the conjunctiva during the allergic response. We determined the interaction of RvD2 with histamine and its receptor subtypes in cultured conjunctival goblet cells and compared them with RvD1 by measuring intracellular [Ca2+] and mucous secretion. Treatment with RvD2 significantly blocked the histamine-induced [Ca2+]i increase as well as secretion. RvD2 and RvD1 counter-regulate different histamine receptor subtypes. RvD2 inhibited the increase in [Ca2+]i induced by the activation of H1, H3, or H4 receptors, whereas RvD1 inhibited H1 and H3 receptors. RvD2 and RvD1 also activate distinct receptor-specific protein kinases to counter-regulate the histamine receptors, probably by phosphorylation. Thus, our data suggest that the counter-regulation of H receptor subtypes by RvD2 and RvD1 to inhibit mucin secretion are separately regulated. 相似文献
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This paper presents a general technique to derive average current mode control (CMC) laws without input voltage sensing to achieve high power factor for single-phase topologies operating in continuous conduction mode (CCM). The control laws are derived based on the steady-state input-output voltage relationships and the CCM large-signal averaged pulsewidth modulation (PWM)-switch model. Using this methodology, average CMC laws with linear PWM waveforms are discovered for commonly used single-phase power stage topologies such as boost, flyback, SEPIC, and buck/boost. Conventional three-loop-controlled average CMC converters can now be controlled with a two-loop architecture. Hardware results for a boost power factor correction (PFC) and simulation results for flyback, SEPIC, and buck/boost topologies verify operation. The small-signal models of the current loop and voltage loop are derived for the boost topology and are used for control loop design. Input current harmonic distortion measurements demonstrate improved performance compared to the conventional three-loop control technique 相似文献
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Holden Mark P.; Curby Kim M.; Newcombe Nora S.; Shipley Thomas F. 《Canadian Metallurgical Quarterly》2010,36(3):590
Memories for spatial locations often show systematic errors toward the central value of the surrounding region. This bias has been explained using a Bayesian model in which fine-grained and categorical information are combined (Huttenlocher, Hedges, & Duncan, 1991). However, experiments testing this model have largely used locations contained in simple geometric shapes. Use of this paradigm raises 2 issues. First, do results generalize to the complex natural world? Second, what types of information might be used to segment complex spaces into constituent categories? Experiment 1 addressed the 1st question by showing a bias toward prototypical values in memory for spatial locations in complex natural scenes. Experiment 2 addressed the 2nd question by manipulating the availability of basic visual cues (using color negatives) or of semantic information about the scene (using inverted images). Error patterns suggest that both perceptual and conceptual information are involved in segmentation. The possible neurological foundations of location memory of this kind are discussed. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
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Effect of raspberry pomace extracts isolated by high pressure extraction on the quality and shelf‐life of beef burgers
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Nora Kryževičūtė Isabel Jaime Ana M. Diez Jordi Rovira Petras Rimantas Venskutonis 《International Journal of Food Science & Technology》2017,52(8):1852-1861
Raspberry pomace extracts isolated with supercritical carbon dioxide (SCE) and pressurised ethanol/water (ETE) were tested in beef burgers. Only ETE additives effectively inhibited lipid oxidation and the growth of microorganisms, as it was observed by measuring the changes of thiobarbituric acid reactive substances, bacterial counts and the content of O2 and CO2 during storage in the modified atmosphere package. ETE additives also demonstrated some meat colour preservation effects, which were assessed by the intensity of hamburger colour and metmyoglobin concentration. However, ETE additives did not alter burger's taste at the applied concentrations (up to 1%). It may be concluded that the most effective extracts possessing strong antioxidant and antimicrobial activity may be isolated from raspberry pomace by the pressurised liquid extraction with a hydroethanolic solvent; such extracts may be considered as promising additives in meat products for improving their stability and enriching with beneficial to health phytochemicals. 相似文献
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Nora MartinezKenji Hisada Isao TabataKazumasa Hirogaki Susumu YonezawaTeruo Hori 《The Journal of Supercritical Fluids》2011,56(3):322-329
The effect of thermal treatment to improve the metal adhesion into poly-(p-phenylene terephthalamide) (PPTA), e.g. aramid fiber, has been investigated. After palladium(II)-hexafluoroacetylacetonate metal complex, Pd(hfac)2, seeding into the fiber using supercritical fluid carbon dioxide, scCO2, a post-thermal treatment was conducted. As a result, after carrying out electroless copper plating, the adhesive strength between polymer substrate and copper layer greatly increased. Also, in order to have a better comprehension on decomposition reactions of Pd(hfac)2 under supercritical conditions, remains of metal complex were analyzed using electron ionization mass spectrometry technique (EI-MS). EI-MS mass spectra derived from Pd(hfac)2 gave us useful information about its dissociation reactions and reaction temperature under supercritical conditions. Additionally, to verify the Pd particles seeding in the fiber surface, X-ray photoelectron spectrometry (XPS) analyses were performed. The results confirmed that post-thermal treatment induced Pd particles diffusion and deeper penetration of Pd complex and its fragments into the fiber. 相似文献
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When working in safety critical environments, such as railway signalling, technologies are often used to assist the operator in order to make safe decisions as well as to increase efficiency. Keeping mental workload at manageable levels is one of the most critical factors to ensure that tasks can be completed in a safe and effective manner. Numerous methods have been used to measure mental workload, but none of these have managed to show the use of distinct resource pools. This paper therefore measures the levels of usage of different cognitive processes when typical tasks are carried out in two railway signalling environments. To that end, the Multiple Resource Questionnaire is used. The aims of this paper are twofold: First, it establishes the value of the Multiple Resource Questionnaire as a technique in human factors. Second, it investigates and compares the cognitive resources required to carry out the railway signalling task in two different signalling environments. 相似文献