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71.
72.
Jose Cesar Rosa Neto Philip C. Calder Rui Curi Philip Newsholme Jaswinder K. Sethi Loreana S. Silveira 《International journal of molecular sciences》2021,22(16)
Macrophages and lymphocytes demonstrate metabolic plasticity, which is dependent partly on their state of activation and partly on the availability of various energy yielding and biosynthetic substrates (fatty acids, glucose, and amino acids). These substrates are essential to fuel-based metabolic reprogramming that supports optimal immune function, including the inflammatory response. In this review, we will focus on metabolism in macrophages and lymphocytes and discuss the role of fatty acids in governing the phenotype, activation, and functional status of these important cells. We summarize the current understanding of the pathways of fatty acid metabolism and related mechanisms of action and also explore possible new perspectives in this exciting area of research. 相似文献
73.
Mertins O Cardoso MB Pohlmann AR da Silveira NP 《Journal of nanoscience and nanotechnology》2006,6(8):2425-2431
In this study we present a full characterization of nanovesicles containing soybean phosphatidylcholine and polysaccharide chitosan. The nanovesicles were prepared by the reverse phase evaporation method, including the preparation of reverse micelles followed by the formation of an organogel, which is dispersed in water to yield the final liposomal particles. Structural changes as a function of the chitosan amount and the filter porosity used in the nanovesicles preparation were studied employing Static and Dynamic Light Scattering as well as Small Angle X-ray Scattering. The hydrodynamic radius of the nanovesicles ranged between 106 and 287 nm, depending on the chitosan contents and the filter porosity. A comparison with nanovesicles free of chitosan indicates the existence of higher contents of multilamellar structures that depends on the chitosan concentration in the vesicles containing chitosan. Typical spherical vesicles having nanometric diameters with polydispersity mostly desired in the biomedical area could only be achieved by filtration through a 0.45 microm porous filter. 相似文献
74.
Silveira LB Martins QS Maia JC Santos JG 《Journal of nanoscience and nanotechnology》2012,12(6):4832-4835
Electrical characterization and magnetic nanocomposite resin seeds Pterodon emarginatus (PE) doped with nanoparticles of maghemite and treated by different chemical processes is reported in this paper. The pure PE resin showed semiconducting characteristics probably the presence of natural iron oxide in its molecular structure. The analysis of M?ssbauer spectra pure resin showed two magnetic sites presented on measurements made at temperature of 300 K. Six "LEDs" to have been doped maghemite nanoparticles forming concentrations of 2.6 x 10(15) to 1.56 x 10(16) particles/cm2 forming the LED-PEMN. In the presence of the applied current versus voltage (0 to 0.9 V) LED-PEMN shown semiconducting properties. In the presence of frequency versus voltage sample of pure resin and LED features small decrease. While samples of LED-PEMN suffers loss frequency linearly with concentration and voltage. The pure PE resin shows high resistance to the applied voltage while the LED-PEMN is observed linear increase with the strength and concentration of nanoparticles of maghemite. 相似文献
75.
Christian Rodriguez Coronado Juliana Tiyoko Yoshioka José Luz Silveira 《Renewable Energy》2011,36(6):1861-1868
Wood gasification technologies to convert the biomass into fuel gas stand out. On the other hand, producing electrical energy from stationary engine is widely spread, and its application in rural communities where the electrical network doesn’t exist is very required. The recovery of exhaust gases (engine) is a possibility that makes the system attractive when compared with the same components used to obtain individual heat such as electric power. This paper presents an energetic alternative to adapt a fixed bed gasifier with a compact cogeneration system in order to cover electrical and thermal demands in a rural area and showing an energy solution for small social communities using renewable fuels. Therefore, an energetic and economical analysis from a cogeneration system producing electric energy, hot and cold water, using wooden gas as fuel from a small-sized gasifier was calculated. The energy balance that includes the energy efficiency (electric generation as well as hot and cold water system; performance coefficient and the heat exchanger, among other items), was calculated. Considering the annual interest rates and the amortization periods, the costs of production of electrical energy, hot and cold water were calculated, taking into account the investment, the operation and the maintenance cost of the equipments. 相似文献
76.
Efficient very‐high‐gravity fermentation of sugarcane molasses by industrial yeast strains
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Heloisy Suzes Barbosa Erick de Abreu Silveira Messias Miranda Jr. José Roberto Ernandes 《Journal of the Institute of Brewing》2016,122(2):329-333
In this study industrial strains were inoculated, in successive cycles, at high cell density into a sugarcane‐based juice containing normal (22%, w/v) and very high sucrose (30%, w/v) levels and supplemented with peptone as a nitrogen source. At 30 °C, in shaken cultures, in the normal gravity situation, efficient sucrose utilization occurred in both the supplemented and unsupplemented medium. At higher sugar concentrations, supplementation with peptone induced a more efficient fermentation compared with the unsupplemented medium, with higher biomass accumulation and maintenance of cell viability, and ethanol levels as high as 16% (v/v). Trehalose was also high during the cycles, probably as a necessary response of the yeast to the high stress fermentation conditions. This suggests that it is possible to increase ethanol production by using very‐high‐fermentation technology and that nutritional supplementation would have a positive effect on the fermentation, allowing for efficient sugar consumption and cell viability maintenance. Copyright © 2016 The Institute of Brewing & Distilling 相似文献
77.
78.
Alexandre B. dos Santos Thiago Vieira Nogueira Coelho Maria José Pontes Daniel Discini Silveira 《Journal of Modern Optics》2013,60(19):1582-1588
This article analyzes the polarization mode dispersion (PMD) in optical fibers and presents a new approach for its measurement. This approach permits the combined analysis of the first-order PMD and the second-order polarization mode dispersion (SOPMD) in optical systems for different values of temperature. The relation between SOPMD and the differential group delay (DGD) in a single-mode fiber is discussed. The analysis is based on time/wavelength and temperature variations changing/impacting PMD and DGD measured values. We present long-term statistical characteristics of SOPMD acquired by a PMD emulator constructed with some pieces of high birefringence fiber, and the correlation between the SOPMD, depolarization (Depol) and polarization-dependent chromatic dispersion (PCD) was investigated. A new interpretation of SOPMD is presented to analyze the problem of the temperature spectral stability. The actual techniques for SOPMD determination, consequently Depol and PCD, use the variation with time and/or wavelength. In some studies, the results obtained for SOPMD are correlated to first-order PMD. We demonstrate experimentally that the temperature is an important factor for the correlation between SOPMD and PMD and cannot be neglected in the optimization of high-speed optical communications links. 相似文献
79.
Alexandre A. Guilherme Mariana S. Silveira Claudia P. M. L. Fontes Sueli Rodrigues Fabiano A. N. Fernandes 《Food and Bioprocess Technology》2012,5(8):3151-3158
The production of lactic acid by Lactobacillus casei B-442 was studied and modeled. Sugar feedstock was provided using cashew apple juice, an alternative glucose and fructose feedstock that proved to yield high concentrations of lactic acid. The fermentations were carried out in a 1-L fermenter under constant agitation (150 rpm) and controlled pH (6.5). Lactic acid production was evaluated through a dynamic study, varying the initial concentration of sugar in the range of 20 to 60 g/L. Biomass, reducing sugars, and lactic acid concentration were measured throughout the experiments. The highest production of lactic acid (59.3 g/L) was obtained operating the fermentation with 60 g/L of reducing sugar from the cashew apple juice. A rigorous kinetic model was developed for batch fermentation of cashew apple juice for lactic acid production by L. casei B-442. The growth of biomass and lactic acid production were affected by substrate limitation, substrate inhibition and lactic acid inhibition. The model assumed growth- and non-growth-associated lactic acid production and a term for microorganism death was also included in the model. Parameters of the kinetic model were determined based on experimental data by using the least mean squares method and Levenberg–Marquardt algorithm. The model validation was performed and the model was statistically able to fit the profiles for growth of biomass, sugar consumption and lactic acid production. The optimization of the process, using the model, was carried out and the optimum operating conditions aiming highest productivity, lowest production cost and highest gross profit are presented. 相似文献
80.
Mariana S. Silveira Cláudia P. M. L. Fontes Alexandre A. Guilherme Fabiano A. N. Fernandes Sueli Rodrigues 《Food and Bioprocess Technology》2012,5(3):947-953
The aim of the present work was to investigate the use of cashew apple juice as a low cost substrate for Lactobacillus casei B-442 cultivation and lactic acid production. Ammonium sulfate was employed as the only exogenous nitrogen source. The effect
of cashew apple juice reducing sugars and ammonium sulfate concentration and the fermentation pH and temperature on biomass
formation, lactic acid production, and productivity were evaluated. The highest productivity (2.36 g/L.h) was obtained applying
50 g/L of reducing sugar from the cashew apple juice supplemented with 6 g/L of ammonium sulfate. The process yield was about
95% when fermentation was carried out at 37 °C with pH controlled at pH 6.5 using NaOH (120 g/L). 相似文献