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991.
Rafael Vercelino Thiago Mattar Cunha Elisa Silva Ferreira Fernando Q. Cunha Sérgio H. Ferreira Marcelo G. de Oliveira 《Journal of materials science. Materials in medicine》2013,24(9):2157-2169
New approaches based on topical treatments are needed for treating pain and impaired dermal blood flow. We used a topical Pluronic F127 hydrogel containing S-nitrosoglutathione (GSNO) as a prodrug to generate free NO, an effector molecule that exerts both dermal vasodilation and antinociceptive effects. GSNO-containing hydrogels underwent gelation above 12 °C and released free NO at rates that were directly dependent on the GSNO concentration in the range of 50–150 mM. The topical application of this material led to dose–response dermal vasodilation in healthy volunteers and to a reduction of up to 50 % of the hypernociception intensity in Wistar rats that were subjected to inflammatory pain. Mechanistic investigations indicated that the antinociceptive effect of the topical F127/GSNO hydrogels is produced by the local activation of the cGMP/PKG/KATP channel-signaling pathway, which was stimulated by the free NO that diffused through the skin. These results expand the scope of the biomedical applications of this material and may represent a new approach for the topical treatment of inflammatory pain. 相似文献
992.
We show that, assuming the existence of collision-resistant hash functions, every language in NP has a constant-round public-coin zero-knowledge argument that remains secure under unbounded parallel composition (a.k.a. parallel zero knowledge.) Our protocol is a variant of Barak’s zero-knowledge argument (FOCS 2001), and has a non-black-box simulator. This result stands in sharp contrast with the recent result by Pass, Tseng and Wikstrom (Crypto 2010) showing that only languages in BPP have public-coin parallel zero-knowledge arguments with black-box simulators. 相似文献
993.
The non-linear electric field dependence of ferroelectric thin films can be used to design frequency and phase agile components. Tunable components have traditionally been developed using mechanically tuned resonant structures, ferrite components, or semiconductor-based voltage controlled electronics, but they are limited by their frequency performance, high cost, high losses, and integration into larger systems. In contrast, the ferroelectric-based tunable microwave component can easily be integrated into conventional microstrip circuits and attributes such as small size, light weight, and low-loss make these components attractive for broadband and multi-frequency applications, many of these components are essential elements in the design of a microwave sensor and/or circuit. It has been reported that with a thin ferroelectric film placed between the top conductor layer and the dielectric material of a microstrip structure, and the proper DC bias scheme, tunable components above the Ku band can be fabricated. Components such as phase shifters, coupled line filters, and Lange couplers have been reported in the literature using this technique. In this work, simulated results from a full wave electromagnetic simulator are obtained to show the tunability of a single stage amplifier. Input and output matching networks are simulated on a ferroelectric thin film to control the frequency response of the amplifier. 相似文献
994.
Pentón D Pérez-Barzaga V Díaz I Reytor ML Campos J Fando R Calvo L Cilli EM Morera V Castellanos-Serra LR Pazos F Lanio ME Alvarez C Pons T Tejuca M 《Protein engineering, design & selection : PEDS》2011,24(6):485-493
The use of pore-forming toxins from sea anemones (actinoporins) in the construction of immunotoxins (ITs) against tumour cells is an alternative for cancer therapy. However, the main disadvantage of actinoporin-based ITs obtained so far has been the poor cellular specificity associated with the toxin's ability to bind and exert its activity in almost any cell membrane. Our final goal is the construction of tumour proteinase-activated ITs using a cysteine mutant at the membrane binding region of sticholysin-I (StI), a cytolysin isolated from the sea anemone Stichodactyla helianthus. The mutant and the ligand moiety would be linked by proteinase-sensitive peptides through the StI cysteine residue blocking the toxin binding region and hence the IT non-specific killing activity. To accomplish this objective the first step was to obtain the mutant StI W111C, and to evaluate the impact of mutating tryptophan 111 by cysteine on the toxin pore-forming capacity. After proteolysis of the cleavage sequence, a short peptide would remain attached to the toxin. The next step was to evaluate whether this mutant is able to form pores even with a residual peptide linked to cysteine 111. In this work we demonstrated that (i) StI W111C shows pore-forming capacity in a nanomolar range, although it is 8-fold less active than the wild-type recombinant StI, corroborating the previously reported importance of residue 111 for the binding of StI to membranes, and (ii) the mutant is able to form pores even with a residual seven-residue peptide linked to cysteine 111. In addition, it was demonstrated that binding of a large molecule to cysteine 111 renders an inactive toxin that is no longer able to bind to the membrane. These results validate the mutant StI W111C for its use in the construction of tumour proteinase-activated ITs. 相似文献
995.
Luc��a Su��rez Pablo Rodr��guez-Calvillo Yvan Houbaert Nelson F. Garza-Montes-de-Oca Rafael Col��s 《Oxidation of Metals》2011,75(5-6):281-295
The deformation of the oxide layer grown in ultra low carbon steel was studied by means of electron backscattered diffraction analyses. Samples of the steel were reheated for shorts periods of time at 1050 °C in a chamber designed to obtain thin scale layers before deforming them by plane strain compression at temperatures ranging from 650 to 1050 °C. Microstructural analyses showed that the oxide layer was made almost exclusively of wustite that is ductile when deformed above 900 °C. It is found that wustite develops texture components of the cube and rotated cube type while growing; these components rotate towards ??201?? {100} components once a certain degree of deformation is achieved. Undeformed ferrite close to the oxide layer shows weak ??201?? {100} components that rotate into weak rotated cube components when the substrate is deformed in the austenite range and to strong ??554?? {225} components when deformed in ferrite. Rolling trials carried out in an experimental mill showed similar trends. 相似文献
996.
997.
998.
Photocatalytic properties of PMMA‐TiO2 class I and class II hybrid nanofibers obtained by electrospinning 下载免费PDF全文
Federico Ohlmaier‐Delgadillo Maria Monica Castillo‐Ortega Rafael Ramírez‐Bon Lorena Armenta‐Villegas Dora Evelia Rodríguez‐Félix Hisila Santacruz‐ Ortega Teresa del Castillo‐Castro Irela Santos‐Sauceda 《应用聚合物科学杂志》2016,133(48)
The preparation, characterization, and photocatalytic activity evaluation of three hybrid fibrous materials composed mainly by poly(methyl methacrylate) (PMMA), methyl methacrylate (MMA): 3‐(trimethoxysilyl) propyl methacrylate (TMSPM): titanium butoxide (TBT), TiO2 nanoparticles (NPTiO2), and TiO2 nanowires (NWTiO2) is studied. Two types of fibe?s structures were prepared, single and core‐shell structures. Scanning electron microscopy (SEM) and transmission electron microscopy (TEM) analysis showed both structures, single and core‐shell, as well as the inorganic phase were dispersed in the hybrid fibers. Infrared spectroscopic analysis (FT‐IR) and thermal analysis showed the organic and inorganic components, as well as the weight percentage of the inorganic phase present in hybrid fibers. The photocatalytic activity of the hybrid fibers class I and II showed that the best photodegradative efficiency for methylene blue in aqueous solution (2.9 × 10?5 M) was 95%, provided by PMMA—10 wt % NPTiO2. © 2016 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2016 , 133, 44334. 相似文献
999.
Rafael M. Santos Jolien Thijs Evangelos Georgakopoulos Yi Wai Chiang Ann Creemers Tom Van Gerven 《Chemical Engineering Communications》2016,203(12):1671-1680
Precipitated aragonite can be synthesized at relatively low temperatures by combining the application of low-frequency sonication with the use of magnesium chloride additive, as demonstrated by our prior study. In the present study, new process conditions were found that promote aragonite formation while accelerating and increasing the reaction yield. It was found that Mg-to-Ca molar ratio of 3:1, together with higher slurry concentration (74 g/L Ca(OH)2) and higher power-to-volume ratio (800 W/L gross, achieved by reducing slurry volume), promoted the aragonite formation while working at a higher CO2 flow rate (2.0 NL/min), and consequently higher precipitated calcium carbonate production rate (1 g/(L · min) CaCO3). The yield was thus improved while conserving the desired product properties as follows: high polymorph purity (95.7 wt%), small and narrow particle size distribution (D[3,2] = 0.74 µm), and unique shape (hubbard squash-like). 相似文献
1000.