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981.
A. O. Lopes E. R. Oliveira D. Smania 《Bulletin of the Brazilian Mathematical Society》2012,43(3):467-512
We consider a piecewise analytic real expanding map f: [0, 1] ?? [0, 1] of degree d which preserves orientation, and a real analytic positive potential g: [0, 1] ?? ?. We assume the map and the potential have a complex analytic extension to a neighborhood of the interval in the complex plane. We also assume log g is well defined for this extension. It is known in Complex Dynamics that under the above hypothesis, for the given potential ?? log g, where ?? is a real constant, there exists a real analytic eigenfunction ? ?? defined on [0, 1] (with a complex analytic extension) for the Ruelle operator of ?? log g. Under some assumptions we show that $\frac{1} {\beta }\log \varphi _\beta$ converges and is a piecewise analytic calibrated subaction. Our theory can be applied when log g(x) = ?log f??(x). In that case we relate the involution kernel to the so called scaling function. 相似文献
982.
G.Z. dos Santos Lima K.C. IaroszA.M. Batista I.L. CaldasZ.O. Guimarães-Filho R.L. VianaS.R. Lopes I.C. NascimentoYu.K. Kuznetsov 《Physics letters. A》2012,376(5):753-757
We analyze long-range time correlations and self-similar characteristics of the electrostatic turbulence at the plasma edge and scrape-off layer in the Tokamak Chauffage Alfvén Brésillien (TCABR), with low and high Magnetohydrodynamics (MHD) activity. We find evidence of self-organized criticality (SOC), mainly in the region near the tokamak limiter. Comparative analyses of data before and during the MHD activity reveals that during the high MHD activity the Hurst parameter decreases. Finally, we present a cellular automaton whose parameters are adjusted to simulate the analyzed turbulence SOC change with the MHD activity variation. 相似文献
983.
We analyze several problems of Optimal Transport Theory in the setting of Ergodic Theory. In a certain class of problems we consider questions in Ergodic Transport which are generalizations of the ones in Ergodic Optimization. Another class of problems is the following: suppose ?? is the shift acting on Bernoulli space X={1,2,??,d}?, and, consider a fixed continuous cost function c:X×X???. Denote by ?? the set of all Borel probabilities ?? on X×X, such that, both its x and y marginals are ??-invariant probabilities. We are interested in the optimal plan ?? which minimizes ??c? d?? among the probabilities in ??. We show, among other things, the analogous Kantorovich Duality Theorem. We also analyze uniqueness of the optimal plan under generic assumptions on c. We investigate the existence of a dual pair of Lipschitz functions which realizes the present dual Kantorovich problem under the assumption that the cost is Lipschitz continuous. For continuous costs c the corresponding results in the Classical Transport Theory and in Ergodic Transport Theory can be, eventually, different. We also consider the problem of approximating the optimal plan ?? by convex combinations of plans such that the support projects in periodic orbits. 相似文献
984.
Portable system of energy dispersive X‐ray fluorescence was used to determine the elemental composition of 68 pottery fragments from ‘Sambaqui do Bacanga’, an archeological site in São Luis, Maranhão, Brazil. This site was occupied from 6600 BP until 900 BP. By determining the element chemical composition of those fragments, it was possible to verify the existence of engobe in 43 pottery fragments. Obtained from two‐dimensional graphs and hierarchical cluster analysis performed in fragments of stratigraphies from surface and 113‐cm level, and 10 to 20, 132 and 144‐cm level, it was possible to group these fragments in five distinct groups, according to their stratigraphies. The results of data grouping (two‐dimensional graphics) are in agreement with hierarchical cluster analysis by Ward method. Copyright © 2011 John Wiley & Sons, Ltd. 相似文献
985.
Walid Zeghbib Fares Boudjouan Vitor Vasconcelos Graciliana Lopes 《Molecules (Basel, Switzerland)》2022,27(15)
Within the Cactaceae family, Opuntia comprises the most widespread species, with a recognized importance in human life, including feeding, domestic use as home natural barriers, and as a traditional remedy for diverse diseases and conditions such asthma, edema, and burns. Indeed, scientific reports have stated that these health benefits may be due to various active compounds, particularly polyphenols, which are ubiquitously found in plants and have proven their pharmacological efficiency by displaying antimicrobial, anti-cancer, and anti-inflammatory activities, among others. Opuntia species contain different classes of phenolic compounds that are recognized for their anti-inflammatory potential. Among them, quercetin, isorhamnetin, and kaempferol derivates were reported to greatly contribute to modulate cells’ infiltration and secretion of soluble inflammatory mediators, with key implications in the inflammatory process. In this review, we make a summary of the different classes of phenolic compounds reported in Opuntia species so far and explore their implications in the inflammatory process, reported by in vitro and in vivo bioassays, supporting the use of cactus in folk medicine and valorizing them from the socio-economic point of view. 相似文献
986.
987.
Cristina M. Alfaia Mnica M. Costa Rui M. A. Pinto Jos M. Pestana Miguel Mourato Patrícia Carvalho Ctia F. Martins Paula A. Lopes Madalena M. Lordelo Jos A. M. Prates 《Molecules (Basel, Switzerland)》2022,27(21)
The effect of a high incorporation level of Ulva lactuca, individually and supplemented with a Carbohydrate-Active enZyme (CAZyme) on broilers’ plasma parameters and liver composition is assessed here. Twenty one-day-old Ross 308 male broilers were randomly assigned to one of four treatments (n = 10): corn/soybean meal based-diet (Control); based-diet with 15% U. lactuca (UL); UL diet with 0.005% of commercial carbohydrase mixture; and UL diet with 0.01% of recombinant ulvan lyase. Supplementing U. lactuca with the recombinant CAZyme slightly compromised broilers’ growth by negatively affecting final body weight and average daily gain. The combination of U. lactuca with ulvan lyase also increased systemic lipemia through an increase in total lipids, triacylglycerols and VLDL-cholesterol (p < 0.001). Moreover, U. lactuca, regardless of the CAZyme supplementation, enhanced hepatic n-3 PUFA (mostly 20:5n-3) with positive decrease in n-6/n-3 ratio. However, broilers fed with U. lactuca with ulvan lyase reduced hepatic α- and γ-tocopherol concentrations relative to the control. Conversely, the high amount of pigments in macroalga diets led to an increase in hepatic β-carotene, chlorophylls and total carotenoids. Furthermore, U. lactuca, alone or combined with CAZymes, enhanced hepatic total microminerals, including iron and manganese. Overall, plasma metabolites and liver composition changed favorably in broilers that were fed 15% of U. lactuca, regardless of enzyme supplementation. 相似文献
988.
Graciliana Lopes Elisabete Gomes Mariana Barbosa Joo Bernardo Patrícia Valento 《Molecules (Basel, Switzerland)》2022,27(22)
Background: The use of plants for therapeutic purposes has been supported by growing scientific evidence. Methods: This work consisted of (i) characterizing the phenolic compounds present in both aqueous and hydroethanol (1:1, v/v) extracts of camel grass, by hyphenated liquid chromatographic techniques, (ii) evaluating their anti-inflammatory, antioxidant, and neuromodulation potential, through in vitro cell and cell-free models, and (iii) establishing a relationship between the chemical profiles of the extracts and their biological activities. Results: Several caffeic acid and flavonoid derivatives were determined in both extracts. The extracts displayed scavenging capacity against the physiologically relevant nitric oxide (•NO) and superoxide anion (O2•−) radicals, significantly reduced NO production in lipopolysaccharide (LPS)-stimulated macrophages (RAW 264.7), and inhibited the activity of hyaluronidase (HAase), acetylcholinesterase (AChE) and butyrylcholinesterase (BChE). Some of these bioactivities were found to be related with the chemical profile of the extracts, namely with 3-caffeoylquinic, 4-caffeoylquinic, chlorogenic, and p-coumaric acids, as well as with luteolin and apigenin derivatives. Conclusions: This study reports, for the first time, the potential medicinal properties of aqueous and hydroethanol extracts of camel grass in the RAW 264.7 cell model of inflammation, and in neurologically related conditions. 相似文献
989.
Atefeh Shafaat Juan Francisco Gonzalez-Martinez Wanderson O. Silva Andreas Lesch Bhawna Nagar Zita Lopes da Silva Jessica Neilands Javier Sotres Sebastian Björklund Hubert Girault Tautgirdas Ruzgas 《Angewandte Chemie (International ed. in English)》2023,62(40):e202308181
Biofilm-associated infections, which are able to resist antibiotics, pose a significant challenge in clinical treatments. Such infections have been linked to various medical conditions, including chronic wounds and implant-associated infections, making them a major public-health concern. Early-detection of biofilm formation offers significant advantages in mitigating adverse effects caused by biofilms. In this work, we aim to explore the feasibility of employing a novel wireless sensor for tracking both early-stage and matured-biofilms formed by the medically relevant bacteria Staphylococcus aureus and Pseudomonas aeruginosa. The sensor utilizes electrochemical reduction of an AgCl layer bridging two silver legs made by inkjet-printing, forming a part of near-field-communication tag antenna. The antenna is interfaced with a carbon cloth designed to promote the growth of microorganisms, thereby serving as an electron source for reduction of the resistive AgCl into a highly-conductive Ag bridge. The AgCl−Ag transformation significantly alters the impedance of the antenna, facilitating wireless identification of an endpoint caused by microbial growth. To the best of our knowledge, this study for the first time presents the evidence showcasing that electrons released through the actions of bacteria can be harnessed to convert AgCl to Ag, thus enabling the wireless, battery-less, and chip-less early-detection of biofilm formation. 相似文献
990.
Mayara Cristina Mombach Lorenz Leandro Silva de Almeida Ana Paula de Oliveira Lopes Inacio Flávio Manoel Rodrigues da Silva Júnior Eliézer Quadro Oreste Daiane Dias 《Electroanalysis》2023,35(7):e202200354
Nowadays, carbon-based materials applied to the development of chemically modified sensors have been highlighted once they can generate methods with high sensitivity, stability, conductivity, accuracy and low cost. Hence, these sensors have been used in environmental monitoring in aneco-friendlyy, sensitive, fast, efficient, inexpensive and robust way. In this review, firstly we described about carbon-based materials and their derivatives, followed by the chemically modified carbon-based sensors manufacturing overview and their applications in environmental analytical chemistry related to inorganic and organic compounds determinations. Future perspectives on trends of the carbon-based materials applications in the sensor modifications are also described. 相似文献