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161.
Wesley Pacheco Calixto A. Paulo Coimbra Jesus Carlos da Mota Marcel Wu Wander G. da Silva Bernardo Alvarenga Leonardo da Cunha Brito Aylton Jose Alves Elder Geraldo Domingues Daywes Pinheiro Neto 《International Journal of Numerical Modelling》2015,28(1):78-95
This work presents a genetic operator developed from mathematical methods of curve extrapolation applied in solving problems in geoelectrical prospection. This operator will assist the production of fitter individuals in the population of a genetic algorithm in which inherent patterns of the best individuals of each generation are recognized. The proposed operator in conjunction with a real‐coded genetic algorithm is compared to five alternative optimization techniques known and used in the application to problems in geoelectrical prospection. Copyright © 2014 John Wiley & Sons, Ltd. 相似文献
162.
Lauane G. Moreno Paulo H. Evangelista-Silva Edivânia C. Santos Rodrigo P. Prates Artenizia C. Lima Mateus F. Mendes Vinícius O. Ottone Marcelo H. F. Ottoni Wagner F. Pereira Gustavo E. B. A. Melo Elizabethe A. Esteves 《European Journal of Lipid Science and Technology》2021,123(9):2000332
Inflammatory bowel diseases (IBD) affect the gastrointestinal tract, and the imbalance of intestinal immune homeostasis can trigger them. Pequi oil (PO), a monounsaturated (MUFA) and carotenoid-rich food with nutraceutical potential, could help reshape the intestinal immune response, ameliorating IBD outcomes. This study investigates the effects of a 28 days intake of PO on elements of the intestinal immune response of mice with DSS-induced ulcerative colitis (disease activity index, colonic damage, inflammatory cells and markers). PO reduces body weight, colonic crypt and goblet cell losses and ameliorates diarrhea. In the colon, it increases γδT cells and secretory-IgA and decreases CD8+T cells. In lymphoid organs, it reduces CD8+T cells. Moreover, it also reduces the IL-17 and CRP in plasma. PO oil promotes a less cytotoxic response that may protect mice from immunological injuries caused by an IBD in the intestinal mucosa, improving the disease prognosis. Practical applications: This study demonstrates that the intake of pequi oil contributes to the regulation of immune response and improves clinical and histological signs of DSS-induced ulcerative colitis in mice. Its effects in cytotoxic cell reduction and other inflammatory markers and stimulation of regulatory cells, and preservation of mucus-producing cells, provide news insights about the importance of the regular intake of this food to better prognosis of ulcerative colitis acute episodes. In addition, these findings encourage further studies with foods with a protective potential for the intestinal mucosa. 相似文献
163.
Renata de A. B. Assis Cíntia H. D. Sagawa Paulo A. Zaini Houston J. Saxe Phillip A. Wilmarth Brett S. Phinney Michelle Salemi Leandro M. Moreira Abhaya M. Dandekar 《International journal of molecular sciences》2021,22(19)
Walnut blight is a significant above-ground disease of walnuts caused by Xanthomonas arboricola pv. juglandis (Xaj). The secreted form of chorismate mutase (CM), a key enzyme of the shikimate pathway regulating plant immunity, is highly conserved between plant-associated beta and gamma proteobacteria including phytopathogens belonging to the Xanthomonadaceae family. To define its role in walnut blight disease, a dysfunctional mutant of chorismate mutase was created in a copper resistant strain Xaj417 (XajCM). Infections of immature walnut Juglans regia (Jr) fruit with XajCM were hypervirulent compared with infections with the wildtype Xaj417 strain. The in vitro growth rate, size and cellular morphology were similar between the wild-type and XajCM mutant strains, however the quantification of bacterial cells by dPCR within walnut hull tissues showed a 27% increase in XajCM seven days post-infection. To define the mechanism of hypervirulence, proteome analysis was conducted to compare walnut hull tissues inoculated with the wild type to those inoculated with the XajCM mutant strain. Proteome analysis revealed 3296 Jr proteins (five decreased and ten increased with FDR ≤ 0.05) and 676 Xaj417 proteins (235 increased in XajCM with FDR ≤ 0.05). Interestingly, the most abundant protein in Xaj was a polygalacturonase, while in Jr it was a polygalacturonase inhibitor. These results suggest that this secreted chorismate mutase may be an important virulence suppressor gene that regulates Xaj417 virulence response, allowing for improved bacterial survival in the plant tissues. 相似文献
164.
Sergiane A. de Araújo Rebeca. D. X. Ribeiro Anny. G. V. O. Lima Thiago V. C. Nascimento Jarbas M. da Silva Júnior Analivia M. Barbosa Paulo R. S. Pimentel Neiri J. A. Santos Leilson. R. Bezerra Elznia S. Pereira Ronaldo L. Oliveira 《European Journal of Lipid Science and Technology》2020,122(8)
This study evaluates the quality of sausage obtained from the meat of Nellore cattle fed diets containing different levels (0, 5, 10, and 15 g per kg total DM) of lauric acid (C12:0) from palm kernel cake. A linear reduction (p ≤ 0.05) in lipid oxidation, as reflected by linear decreases in the lightness (L*), yellowness (b*), and saturation (C*) color parameters, is observed on days 7, 14, and 21 of maturation of sausage, and these decreases are accompanied by linear increases in the redness (a*) color and the linoleic (C18:2n–6) and linolenic (C18:3n–3) fatty acid contents. The inclusion of lauric acid in the diet induces linear reductions in the shear force and cooking loss and does not significantly affect various indices, including the centesimal composition, water activity, water holding capacity, composition of most fatty acids (FA), hypocholesterolemic‐to‐hypercholesterolemic FA ratio, atherogenicity, thrombogenicity, and desirable fatty acids. The use of dietary lauric acid from palm kernel cake is recommended at doses up to 15 g per kg because its presence reduces lipid oxidation and improves color parameters, softness, and linoleic and linolenic FA without affecting the FA composition of sausage from Nellore bull's meat. Practical applications : Sausages are products manufactured from chopped or ground meats packaged into animal casings. This product appeared in Brazil through the adaptation of traditional recipes brought by German and Italian immigrant families to weather conditions and the national palate. However, due to its production characteristics, sausage can become a product with lipid characteristics that are undesirable for human consumption. The inclusion of lauric acid (C12:0) in the animal diet might change the biohydrogenation process in the rumen, improve the quality of the deposited FA and reduce lipid oxidation in sausage manufactured from meat. The FA composition and physicochemical properties of sausage predict its acceptance by the consumer market. An optimal advantage would be achieved if these products can be used as not only preservatives but also functional ingredients with antioxidant properties and products for the treatment of metabolic syndrome and cardiovascular diseases through atherogenic action. 相似文献
165.
Ingrid Lessa Leal Yasmin Carolino da Silva Rosa Josenai da Silva Penha Paulo Romano Cruz Correia Pollyana da Silva Melo Danilo Hansen Guimarães Josiane Dantas Viana Barbosa Janice Izabel Druzian Bruna Aparecida Souza Machado 《应用聚合物科学杂志》2019,136(43):48150
In this study, formulations of cassava starch and poly(butylene adipate-co-terephthalate) flexible films were developed, with glycerol, coconut nanocellulose, annatto, and citric acid in different concentrations, as well as the effectiveness of the selected materials in fresh-cut mangoes storage was evaluated. The tensile strength of the different formulations varied from 1.90 (E4) to 6.65 MPa (E3c), and the strain varied from 206.31 (E1c) to 278.41% (E8); this variation was dependent on the percentage of the polymer matrix incorporated. The aw values of the formulations ranged from 0.396 (E2) to 0.569 (E3c). The Formulations E4 and E7 (with additives) presented good properties and were selected to condition mangoes. The micrographs of these films showed regions of micropores that can facilitate the diffusion of water from the packaged product to the surface, allowing decreases in moisture and aw, which is associated with higher color maintenance during fruit storage. E7 presented better barrier properties than E4 (lower values of WVP and water solubility) which may have influenced in a positive way to maintain the stability of the package in the studied period. E7 can be considered as a viable alternative for minimally processed mango storage. © 2019 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2019 , 136, 48150. 相似文献
166.
Ranulfo Benedito de Paula Miranda Roger Borges Juliana Marchi Nelson Batista de Lima Paulo Francisco Cesar 《International Journal of Applied Ceramic Technology》2019,16(5):1979-1988
The addition of bioactive glasses to a Y:TZP matrix represents a feasible alternative to provide bioactivity to this material and optimize osseointegration. This work evaluated the effect of the BG concentration (0 and 10 wt%) and the sintering temperature (1200°C and 1300°C) on the microstructure, relative density, and flexural strength of the composite Y:TZP/BG. The Y:TZP and Y:TZP/BG powders were uniaxially pressed and sintered at 1200°C or 1300°C for 1 h. The microstructure was characterized by X-ray diffraction analysis, scanning electron microscopy, and energy-dispersive X-ray Spectroscopy. Relative density was calculated from density values obtained using the Archimedes’ principle. For the flexural strength, specimens (n = 6) were fractured in a biaxial flexural setup using a piston-on-three-balls fixture in a universal testing machine. Bioactivity test was performed in simulated body fluid solution. The results suggested that BG addition decreased the grain size of the composite, increased porosity and caused a significant decrease in the relative density and flexural strength. Crystalline phases of calcium stabilized cubic zirconia and sodium zirconium silicate were formed after the addition of BG. Finally, it was concluded that composite specimens sintered at 1300°C showed the highest density values and larger grains compared to those sintered at 1200°C. 相似文献
167.
João Paulo Ferreira Santos Benjamim de Melo Carvalho Rosario Elida Suman Bretas 《应用聚合物科学杂志》2019,136(17):47409
Poly(vinylidene fluoride) (PVDF) nanocomposites have plenty of applications in the electronic realm. In this study, we produced nanocomposites based on PVDF and multiwalled carbon nanotubes (MWCNTs), with various MWCNT loadings, using three different processing routes: solution mixing, melt mixing, and electrospinning. The broadband electrical behavior of these nanocomposites was studied and compared via impedance spectroscopy. The morphologies of the nanocomposites were characterized by transmission electron microscopy and scanning electron microscopy. The results reveal that the electrical behaviors of the samples were completely different according to the processing route used. Solution mixing was the most suitable method for producing nanocomposites with the highest conductivities, at low MWCNT loadings, whereas electrospinning was the most suitable method for producing nanocomposites with the lowest dielectric permittivity. These differences were attributed to the different arrangements of the MWCNTs caused by the different processes. Although the solution-mixed samples exhibited long and twisted MWCNTs, the melt-mixed samples had shorter MWCNTs, and the electrospun samples had MWCNTs embedded and aligned inside the insulating polymer nanofibers. Thus, these results project a vast horizon for tailoring the structure and thereby the broadband electrical behavior of PVDF–MWCNT nanocomposites for different types of applications. © 2018 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2019 , 136, 47409. 相似文献
168.
169.
Bruno R. S. Paula Davila Zampieri J. Augusto R. Rodrigues Paulo J. S. Moran 《Advanced Synthesis \u0026amp; Catalysis》2016,358(22):3555-3571
(Z)‐3‐Acetoxymethyl‐4‐R‐3‐buten‐2‐ones (R=aryl, alkyl) and (Z)‐3‐methyl‐4‐R‐3‐buten‐2‐ones (R=aryl) were synthesized and submitted to reduction by the yeast Saccharomyces cerevisiae producing the (R)‐ and (S)‐4‐R‐3‐methybutan‐2‐ones, respectively. This stereochemistry control strategy was applied in the syntheses of (R)‐ and (S)‐Tropional® with moderate to high enantiomeric excesses. Other (Z)‐3‐acyloxymethyl‐4‐phenyl‐3‐buten‐2‐ones showed similar behavior to the (Z)‐3‐acetoxymethyl counterpart, and the acylated Morita–Baylis–Hillman adduct 1‐acetoxy‐2‐methylene‐1‐phenylbutan‐3‐one produced a mixture of products, with and without the acetoxy group, via three different reaction pathways. In addition to experiments employing whole cells, those in which isolated enereductases were used suggested that the main pathway through which the loss of the acetoxy group occurs during the biocatalytic cascade is an SN2′‐type reaction, rather than formal hydrogen addition followed by acetic acid elimination. Finally, related ethyl enones were reduced enantioselectively by the yeast Candida albicans, producing both (R)‐ and (S)‐reduction products, depending on the presence of the acetoxy group in the starting material.
170.
Paulo Ronaldo Sousa Teixeira Ana Siqueira do Nascimento Marreiro Teixeira Emanuel Airton de Oliveira Farias Durcilene Alves da Silva Lívio César Cunha Nunes Cleide Maria da Silva Leite Edson Cavalcanti da Silva Filho Carla Eiras 《Journal of Polymer Research》2018,25(5):127
The babassu coconut is a plant very abundant in northeast of Brazil and other countries, and any part of plant and fruit becomes residue. In this study, babassu mesocarp (Orbignya sp) (BM) was chemically modified with phthalic anhydride (BMPA) to increase its solubility in an aqueous medium, and thus facilitate its processing in the form of thin films. The reaction of modification of the babassu mesocarp with phthalic anhydride (PA), obtaining BMPA, was confirmed by FTIR, XRD, TG/DTG, Zeta Potential and SEM analysis, from the differences in the bands of the FTIR spectra, increase in crystallinity, new thermal profile, changes in zeta potential value and morphology, respectively. The thin monolayer films of BM and BMPA were produced by the self-assembly monolayer (SAM) technique, and adsorbed onto conductive glass substrates (tin-doped indium oxide, ITO). The electroactive properties of these thin films were evaluated by cyclic voltammetry (CV). BM exhibited a pair redox pair process of +0.57 V(oxidation) and?+?0.19 V (reduction) for BM. In BMPA these redox processes were observed at +0.37 V (oxidation) and 0.24 V vs. ECS (reduction), verifying that both BM and BMPA are electroactive materials that can be used in the construction of sensor platforms, without the necessity of being conjugated with other electroactive materials, such as conductive polymers, metal phthalocyanines, or dyes. Furthermore, under the experimental conditions used, the BMPA presented a more reversible redox process and higher electrochemical stability in comparison to BM. This effect occurs because BMPA has higher solubility in aqueous media, which favors the preparation of films with smaller grain sizes compared to BM films, as observed by Atomic Force Microscopy (AFM). This study showed that BMPA is a new material with potential for applications in electrochemical sensors. 相似文献