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41.
42.
Marina Martinez-Vargas Julio Morales-Gomez Ruben Gonzalez-Rivera Carla Hernandez-Enriquez Adan Perez-Arredondo Francisco Estrada-Rojo Luz Navarro 《International journal of molecular sciences》2013,14(12):23341-23355
The endocannabinoid system is a component of the neuroprotective mechanisms that an organism displays after traumatic brain injury (TBI). A diurnal variation in several components of this system has been reported. This variation may influence the recovery and survival rate after TBI. We have previously reported that the recovery and survival rate of rats is higher if TBI occurs at 1:00 than at 13:00. This could be explained by a diurnal variation of the endocannabinoid system. Here, we describe the effects of anandamide administration in rats prior to the induction of TBI at two different times of the day: 1:00 and 13:00. We found that anandamide reduced the neurological damage at both times. Nevertheless, its effects on bleeding, survival, food intake, and body weight were dependent on the time of TBI. In addition, we analyzed the diurnal variation of the expression of the cannabinoid receptors CB1R and CB2R in the cerebral cortex of both control rats and rats subjected to TBI. We found that CB1R protein was expressed more during the day, whereas its mRNA level was higher during the night. We did not find a diurnal variation for the CB2R. In addition, we also found that TBI increased CB1R and CB2R in the contralateral hemisphere and disrupted the CB1R diurnal cycle. 相似文献
43.
Felipe C. da Silva Carolina Rodrigues da Fonseca Severino Matias de Alencar Marcelo Thomazini Julio C. de Carvalho Balieiro Paola Pittia Carmen Sílvia Favaro-Trindade 《Food and Bioproducts Processing》2013,91(1):28-36
The aim of this work was to obtain propolis in a powder, alcohol-free, water-dispersed and shelf-stable form. Propolis extract was spray-dried using gum Arabic and octenyl succinic anhydride (OSA) starch as carriers in two different weight ratios (1:4 and 1:6). Spray-dried propolis samples were evaluated for morphology, moisture, water activity, water dispersibility, hygroscopicity, particle size, particle distribution, entrapping efficiency, stability, isotherms and antioxidant properties. The spray-drying process produced round particles with sizes ranging from 15 to 24 μm. This process preserved the antioxidant activity of propolis and also allowed propolis to be obtained in a powder form, which was stable during storage at room temperature, had low hygroscopicity and was highly dispersible in cold water. The application of this technology could increase the use of propolis in various industrial applications, such as an antimicrobial and as an antioxidant in food. 相似文献
44.
Air gasification of different biomass fuels, including forestry (pinus pinaster pruning) and agricultural (grapevine and olive tree pruning) wastes as well as industry wastes (sawdust and marc of grape), has been carried out in a circulating flow gasifier in order to evaluate the potential of using these types of biomass in the same equipment, thus providing higher operation flexibility and minimizing the effect of seasonal fuel supply variations. The potential of using biomass as an additional supporting fuel in coal fuelled power plants has also been evaluated through tests involving mixtures of biomass and coal–coke, the coke being a typical waste of oil companies. The effect of the main gasifier operating conditions, such as the relative biomass/air ratio and the reaction temperature, has been analysed to establish the conditions allowing higher gasification efficiency, carbon conversion and/or fuel constituents (CO, H2 and CH4) concentration and production. Results of the work encourage the combined use of the different biomass fuels without significant modifications in the installation, although agricultural wastes (grapevine and olive pruning) could to lead to more efficient gasification processes. These latter wastes appear as interesting fuels to generate a producer gas to be used in internal combustion engines or gas turbines (high gasification efficiency and gas yield), while sawdust could be a very adequate fuel to produce a H2-rich gas (with interest for fuel cells) due to its highest reactivity. The influence of the reaction temperature on the gasification characteristics was not as significant as that of the biomass/air ratio, although the H2 concentration increased with increasing temperature. 相似文献
45.
Due to the increase in the number and popularity of applications such as e-commerce or on-line booking systems, typical of the Web 2.0, dynamic contents are becoming more and more frequent. This trend suggests the review of widely accepted paradigms and models for the World Wide Web. As a system that is continuously changing, both in the offered applications and in its infrastructure, performance evaluation studies are a main concern to provide sound proposals when designing new web-related systems. Although the dynamism in the workload characterization has also been tackled in previous research, it has not been modeled in a precise way yet because of its complex nature.In this paper we propose the Dweb model which represents the dynamism of current web applications in the workload characterization. Dweb is based on three main concepts that allow to model dynamic workload: navigation, workload test and workload distribution. In addition, a dynamic workload generator has been implemented to show the practical application of the proposed model, which has been illustrated through a case study. 相似文献
46.
Cristina Megías Elena Pastor-Cavada Cristina Torres-Fuentes Julio Girón-Calle Manuel Alaiz Rocio Juan Julio Pastor Javier Vioque 《European Food Research and Technology》2009,230(2):353-359
The metal chelating activity, antioxidant properties, and the effect on cell growth of a polyphenol extract from Vicia sativa have been investigated, and compared to those of soybean. The extracts from V. sativa seeds contained three and five times more polyphenols and flavonoids than soybean, respectively. The soybean polyphenol extracts showed higher copper and iron chelating activity than those from V. sativa, although polyphenols from V. sativa were more effective in preventing β-carotene oxidation and showed higher reducing power and scavenging activity than soybean polyphenols. In addition, V. sativa polyphenols were toxic to THP-1 leukemic cells, as opposed to polyphenols extracted from soybean that did not show any antiproliferative activity at similar concentrations. In conclusion, V. sativa polyphenol extracts show promising antioxidant and antiproliferative activities that may be of interest from a functional point of view and for the revalorization of this ancient crop. 相似文献
47.
Otto Julio Ahlert Pinno Andr Ricardo Abed Grgio Luis C.E. De Bona 《Concurrency and Computation》2020,32(12)
The IoT is changing the way we interact with the world. Very soon, almost all of our daily tasks will be made through self intelligent systems embedded in devices scattered all around us. Their mission is to turn our cities, transportation systems, buildings, homes, and bodies in smart environments. These environments will bring us more comfort, improve our performance, increase our profits, and take away time‐consuming tasks. However, besides its great benefits, the IoT is also a big source of concerns, mainly because a good part of its devices will handle private and confidential information. Recently, cases of successful IoT invasions only worsen this scenario and show us that the today's adopted access control systems need to be replaced by more efficiently and secure ones. To overcome these access control problems, in this work, we present the ControlChain. The ControlChain is an access control authorization architecture that is heavily based on Blockchain technology. We also demonstrate the viability of the ControlChain through the E‐ControlChain, a proof‐of‐concept developed to run over the Ethereum network. Our proposals follows the IoT tendency requirements and are user‐transparent, user‐friendly, fully decentralized, scalable, fault tolerant, and compatible with a wide range of today's access control models already used in the IoT. Finally, we also make a cost and a performance analysis of E‐ControlChain, using a Raspberry Pi as an IoT device. 相似文献
48.
Julio Moreno Javier Gómez Manuel A. Serrano Eduardo B. Fernandez Eduardo Fernández-Medina 《Software》2020,50(8):1520-1538
Big Data environments are typically very complex ecosystems; this means that implementing them is complicated. One possible technique with which to address this complexity is the use of abstraction. Reference architecture (RA) can be useful for an improved understanding of the main components of Big Data. Herein, we propose a security RA that includes the management of security concerns and provides the main elements of a Big Data ecosystem. Application of this architecture to real-world scenarios facilitates its refinement and improves its usefulness. In this article, we present a case study of a real-world Big Data ecosystem implemented in a banking environment. This ecosystem was developed by everis, an NTT company with which we collaborated for this study. To conduct this validation case study, a map was established between the elements of the Big Data ecosystem implemented and our proposal. Consequently, a series of valuable lessons that can improve both our architecture and the security of the Big Data environment were obtained. These include recommendations for a set of best practices such as the use of security patterns. 相似文献
49.
Ignacio Peñarrocha Daniel Dolz Julio Ariel Romero Roberto Sanchis 《International journal of systems science》2016,47(2):283-299
This work presents a strategy to minimise the network usage and the energy consumption of wireless battery-powered sensors in the observer problem over networks. The sensor nodes implement a periodic send-on-delta approach, sending new measurements when a measure deviates considerably from the previous sent one. The estimator node implements a jump observer whose gains are computed offline and depend on the combination of available new measurements. We bound the estimator performance as a function of the sending policies and then state the design procedure of the observer under fixed sending thresholds as a semidefinite programming problem. We address this problem first in a deterministic way and, to reduce conservativeness, in a stochastic one after obtaining bounds on the probabilities of having new measurements and applying robust optimisation problem over the possible probabilities using sum of squares decomposition. We relate the network usage with the sending thresholds and propose an iterative procedure for the design of those thresholds, minimising the network usage while guaranteeing a prescribed estimation performance. Simulation results and experimental analysis show the validity of the proposal and the reduction of network resources that can be achieved with the stochastic approach. 相似文献
50.
Leonardo Albarracin Ramiro Ortiz Moyano Juan Martin Vargas Bruno G. N. Andrade Juan Cortez Zamar Stefania Dentice Maidana Kohtaro Fukuyama Shoichiro Kurata María ngela Jure Haruki Kitazawa Julio Villena 《International journal of molecular sciences》2022,23(13)
In recent years, an increase in the prevalence hypermucoviscous carbapenem-resistant Klebsiella pneumoniae with sequence type 25 (ST25) was detected in hospitals of Tucuman (Northwest Argentina). In this work, the virulence and the innate immune response to two K. pneumoniae ST25 strains (LABACER 01 and LABACER 27) were evaluated in a murine model after a respiratory challenge. In addition, comparative genomics was performed with K. pneumoniae LABACER01 and LABACER27 to analyze genes associated with virulence. Both LABACER01 and LABACER27 were detected in the lungs of infected mice two days after the nasal challenge, with LABACER01 counts significantly higher than those of LABACER27. Only LABACER01 was detected in hemocultures. Lactate dehydrogenase (LDH) and albumin levels in bronchoalveolar lavage (BAL) samples were significantly higher in mice challenged with LABACER01 than in LABACER27-infected animals, indicating greater lung tissue damage. Both strains increased the levels of neutrophils, macrophages, TNF-α, IL-1β, IL-6, KC, MCP-1, IFN-γ, and IL-17 in the respiratory tract and blood, with the effect of LABACER01 more marked than that of LABACER27. In contrast, LABACER27 induced higher levels of IL-10 in the respiratory tract than LABACER01. Genomic analysis revealed that K. pneumoniae LABACER01 and LABACER27 possess virulence factors found in other strains that have been shown to be hypervirulent, including genes required for enterobactin (entABCDEF) and salmochelin (iroDE) biosynthesis. In both strains, the genes of toxin–antitoxin systems, as well as regulators of the expression of virulence factors and adhesion genes were also detected. Studies on the genetic potential of multiresistant K. pneumoniae strains as well as their cellular and molecular interactions with the host are of fundamental importance to assess the association of certain virulence factors with the intensity of the inflammatory response. In this sense, this work explored the virulence profile based on genomic and in vivo studies of hypermucoviscous carbapenem-resistant K. pneumoniae ST25 strains, expanding the knowledge of the biology of the emerging ST25 clone in Argentina. 相似文献