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701.
M. E. Borges T. Hernández P. Esparza 《Clean Technologies and Environmental Policy》2014,16(2):431-436
Heterogeneous UV-photocatalytic process has been studied as tertiary treatment of real municipal wastewater. Wastewater photocatalytic treatment was carried out using several materials previously developed as photocatalysts: volcanic ashes and nanostructured titania supported over volcanic ashes. Both material activities in particles were compared with Degussa TiO2 (powder). Photocatalyst amount influence was studied by varying it between 2 and 10 g L?1. Wastewater decontamination process was evaluated measuring the chemical oxygen demand evolution with phototreatment time in order to choose the best photocatalytic material and its optimal operation concentration. Moreover, the photocatalytic results obtained were compared with those obtained from photolysis and adsorption studies in wastewater using the same operation conditions. In addition, analyses of main wastewater parameters were made in order to evaluate the complete water decontamination process. Possibility of using photocatalysts in particles shows the main advantage of continuous photocatalyst separation from the water effluent once the decontamination process has finished. Good photocatalytic activities were observed, and it allows to conclude that heterogeneous photocatalysis is an effective method for municipal wastewater treatment, achieving water disinfection and phosphates removal. 相似文献
702.
703.
Elisa Flávia Luiz Cardoso Bail?o Ivano Alessandro Devilla Edemilson Cardoso da Concei??o Leonardo Luiz Borges 《International journal of molecular sciences》2015,16(10):23760-23783
Functional foods include any natural product that presents health-promoting effects, thereby reducing the risk of chronic diseases. Cerrado fruits are considered a source of bioactive substances, mainly phenolic compounds, making them important functional foods. Despite this, the losses of natural vegetation in the Cerrado are progressive. Hence, the knowledge propagation about the importance of the species found in Cerrado could contribute to the preservation of this biome. This review provides information about Cerrado fruits and highlights the structures and pharmacologic potential of functional compounds found in these fruits. Compounds detected in Caryocar brasiliense Camb. (pequi), Dipteryx alata Vog. (baru), Eugenia dysenterica DC. (cagaita), Eugenia uniflora L. (pitanga), Genipa americana L. (jenipapo), Hancornia speciosa Gomes (mangaba), Mauritia flexuosa L.f. (buriti), Myrciaria cauliflora (DC) Berg (jabuticaba), Psidium
guajava L. (goiaba), Psidium spp. (araçá), Solanum lycocarpum St. Hill (lobeira), Spondias mombin L. (cajá), Annona crassiflora Mart. (araticum), among others are reported here. 相似文献
704.
Daiane Damasceno Borges Paul Fabry Thomas Devic Michael T. Wharmby Charlotte Martineau Damien Foucher Francis Taulelle Chul‐Ho Jun Young Kyu Hwang Norbert Stock Martijn F. De Lange Freek Kapteijn Jorge Gascon Guillaume Maurin Jong‐San Chang Christian Serre 《Advanced materials (Deerfield Beach, Fla.)》2015,27(32):4775-4780
705.
706.
Sérgio C. Mannarino Leonardo F. Vilela Aline A. Brasil Juliana N. Aranha Pedro Moradas‐Ferreira Marcos D. Pereira Vítor Costa Elis C. A. Eleutherio 《Yeast (Chichester, England)》2011,28(1):19-25
It has been shown that the activation of cytosolic superoxide dismutase (Sod1) in Saccharomyces cerevisiae is only dependent on Ccs1, which is responsible for insertion of copper into the enzyme catalytic center, and that glutathione (GSH) is not necessary for this process. In this work, we addressed an important role of GSH in Sod1 activation by a Ccs1‐dependent mechanism during oxidative stress and its role in yeast lifespan. Exponential cells of Saccharomyces cerevisiae, treated or not with 0.5 mM menadione for 1 h, were used for evaluation of the effect of a mild oxidative stress pre‐treatment on chronological lifespan. The results showed that menadione induced a lifespan extension in the wild‐type (WT) strain but this adaptive response was repressed in gsh1 and in sod1 strains. Interestingly, menadione treatment increased SOD1 and CCS1 gene expression in both WT and gsh1 strains. However, while these strains showed the same Sod1 activity before treatment, only the WT presented an increase of Sod1 activity after menadione exposure. Glutathionylation seems to be essential for Sod1 activation since no increase in activity was observed after menadione treatment in grx1 and grx2 null mutants. Our results suggest that GSH and glutathionylation are fundamental to protect Sod1 sulfhydryl residues under mild oxidative stress, enabling Sod1 activation and lifespan extension. Copyright © 2010 John Wiley & Sons, Ltd. 相似文献
707.
Insight into the Interactions between Novel Coumarin Derivatives and Human A3 Adenosine Receptors 下载免费PDF全文
Dr. Maria João Matos Dr. Santiago Vilar Dr. Sonja Kachler André Fonseca Prof. Lourdes Santana Prof. Eugenio Uriarte Prof. Fernanda Borges Dr. Nicholas P. Tatonetti Prof. Karl‐Norbert Klotz 《ChemMedChem》2014,9(10):2245-2253
A study focused on the discovery of new chemical entities based on the 3‐arylcoumarin scaffold was performed with the aim of finding new adenosine receptor (AR) ligands. Thirteen synthesized compounds were evaluated by radioligand binding (A1, A2A, and A3) and adenylyl cyclase activity (A2B) assays in order to study their affinity for the four human AR (hAR) subtypes. Seven of the studied compounds proved to be selective A3AR ligands, with 3‐(4′‐methylphenyl)‐8‐(2‐oxopropoxy)coumarin ( 12 ) being the most potent (Ki=634 nM ). None of the compounds showed affinity for the A2B receptor, while four compounds were found to be nonselective AR ligands for the other three subtypes. Docking simulations were carried out to identify the hypothetical binding mode and to rationalize the interaction of these types of coumarin derivatives with the binding site of the three ARs to which binding was observed. The results allowed us to conclude that the 3‐arylcoumarin scaffold composes a novel and promising class of A3AR ligands. ADME properties were also calculated, with the results suggesting that these compounds are promising leads for the identification of new drug candidates. 相似文献
708.
Borges PD Scolfaro LM Leite Alves HW da Silva EF Assali LV 《Nanoscale research letters》2011,6(1):146
In this article, using first-principles electronic structure calculations within the spin density functional theory, alternated
magnetic and non-magnetic layers of rutile-CrO2 and rutile-SnO2 respectively, in a (CrO2)
n
(SnO2)
n
superlattice (SL) configuration, with n being the number of monolayers which are considered equal to 1, 2, ..., 10 are studied. A half-metallic behavior is observed
for the (CrO2)
n
(SnO2)
n
SLs for all values of n. The ground state is found to be FM with a magnetic moment of 2 μB per chromium atom, and this result does not depend on the number of monolayers n. As the FM rutile-CrO2 is unstable at ambient temperature, and known to be stabilized when on top of SnO2, the authors suggest that (CrO2)
n
(SnO2)
n
SLs may be applied to spintronic technologies since they provide efficient spin-polarized carriers. 相似文献
709.
Bluma G. Soares Marlucy de Oliveira Soraia Zaioncz Ana C. O. Gomes Adriana A. Silva Kelly S. Santos Raquel S. Mauler 《应用聚合物科学杂志》2011,119(1):505-514
A comparative study of the development of nitrile rubber (NBR) based nanocomposites was performed; two organomontmorillonites (Cloisite 15A and Cloisite 30B) and two procedures for clay dispersion (melt blending and solution intercalation) were used. The nanocomposites were cured with a system based on dicumyl peroxide in the presence of m‐phenylenebismaleimide as a coagent for curing. The dispersion of the organoclay inside the NBR matrix was investigated with transmission electron microscopy and X‐ray diffraction. All the cured systems displayed a combination of intercalated, partially exfoliated clay platelets and confined, deintercalated clay; the degree of dispersion depended on the amount of clay, the type of intercalant, and the intercalation procedure. The highest amount of intercalated/exfoliated clay was obtained with a previous dispersion of the clay (Cloisite 30B) in an NBR solution. All the nanocomposites presented outstanding tensile strength and creep response, and this indicated a reinforcing effect of the layered silicates. © 2010 Wiley Periodicals, Inc. J Appl Polym Sci, 2011 相似文献
710.
In order for biodiesel to be commercialized as pure biofuel or blending stock for diesel fuels, it must meet a set of requirements defined in standard specifications for a safe and satisfactory engine operation, one of these specifications is the content of fatty acid methyl esters (FAME). Besides, this parameter indicates the performance of the transesterification reaction for biofuel production from vegetable oils. There are several methods to determinate FAME content in biodiesel samples (chromatography, nuclear magnetic resonance spectroscopy and FTIR spectroscopy); however, they take long times and high cost for FAME content determination. From a practical point of view, in industrial biodiesel production is usually necessary to estimate the FAME value quickly. This paper presents correlations experimentally obtained from different oil feedstocks in order to estimate the biodiesel FAME content from the biodiesel dynamic viscosity, a fast determination parameter. 相似文献