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排序方式: 共有261条查询结果,搜索用时 10 毫秒
251.
Letícia Dias de Melo Carrasco Jorge Luiz Mello Sampaio Ana Maria Carmona-Ribeiro 《International journal of molecular sciences》2015,16(3):6337-6352
The growing challenge of antimicrobial resistance to antibiotics requires novel synthetic drugs or new formulations for old drugs. Here, cationic nanostructured particles (NPs) self-assembled from cationic bilayer fragments and polyelectrolytes are tested against four multidrug-resistant (MDR) strains of clinical importance. The non-hemolytic poly(diallyldimethylammonium) chloride (PDDA) polymer as the outer NP layer shows a remarkable activity against these organisms. The mechanism of cell death involves bacterial membrane lysis as determined from the leakage of inner phosphorylated compounds and possibly disassembly of the NP with the appearance of multilayered fibers made of the NP components and the biopolymers withdrawn from the cell wall. The NPs display broad-spectrum activity against MDR microorganisms, including Gram-negative and Gram-positive bacteria and yeast. 相似文献
252.
Comparison of Response Surface Methodology and Artificial Neural Network for Modeling Xylose‐to‐Xylitol Bioconversion 下载免费PDF全文
Fábio Coelho Sampaio Janaína Teles de Faria Gabriel Dumond de Lima Silva Ricardo Melo Gonçalves Cristiano Grijó Pitangui Alessandro Alberto Casazza Saleh Al Arni Attilio Converti 《化学工程与技术》2017,40(1):122-129
Previous experimental data of xylose‐to‐xylitol bioconversion by Debaryomyces hansenii carried out according to a 33 full factorial design were used to model this process by two different artificial neural network (ANN) training methods. Models obtained for four responses were compared with those of response surface methodology (RSM). ANN models were shown to be superior to RSM in the predictive capacity, whereas the latter showed better performance in the generalization capability step. RSM with optimization using a genetic algorithm was revealed as a whole to be the best modeling option, which suggests that the comparative performances of RSM and ANN may be a highly problem‐specific issue. 相似文献
253.
D.V. Sampaio M.S. Silva N.R.S. Souza J.C.A. Santos M.V.S. Rezende R.S. Silva 《Ceramics International》2018,44(13):15526-15530
In this work, we introduce a simple, low-cost, and ecofriendly method for producing barium titanate (BaTiO3–BT) and barium calcium titanate (Ba0.77Ca0.23TiO3–BCT) powders. The synthesis was performed by using a proteic sol–gel route which use coconut water in the polymerization step of the metallic precursor. We investigated the effects of the processing parameters with the density, microstructure, and (di)electric properties as sample quality indicators. The sintered ceramics exhibit single crystalline phase, relative density of 95%, a homogeneous microstructure, and an average grain size of 4?µm. The respective dielectric constants of 1200 (BT) and 700 (BCT), measured at room temperature, and the activation energy values for the conductive process are according to those reported in the literature for conventionally prepared ceramics. 相似文献
254.
255.
Rodrigo Zamignan Carpi Sandra M. Barbalho Katia Portero Sloan Lucas Fornari Laurindo Heron Fernando Gonzaga Paulo Cesar Grippa Tereza L. Menegucci Zutin Raul J. S. Girio Cludia Sampaio Fonseca Repetti Cludia Rucco Penteado Detregiachi Patrícia C. Santos Bueno Eliana de Souza Bastos Mazuqueli Pereira Ricardo de Alvares Goulart Jesselina Francisco dos Santos Haber 《International journal of molecular sciences》2022,23(15)
Modifications in the microbiota caused by environmental and genetic reasons can unbalance the intestinal homeostasis, deregulating the host’s metabolism and immune system, intensifying the risk factors for the development and aggravation of non-alcoholic fat liver disease (NAFLD). The use of probiotics, prebiotics and synbiotics have been considered a potential and promising strategy to regulate the gut microbiota and produce beneficial effects in patients with liver conditions. For this reason, this review aimed to evaluate the effectiveness of probiotics, prebiotics, and symbiotics in patients with NAFLD and NASH. Pubmed, Embase, and Cochrane databases were consulted, and PRISMA (Preferred Reporting Items for Systematic Reviews and Meta-Analysis) guidelines were followed. The clinical trials used in this study demonstrated that gut microbiota interventions could improve a wide range of markers of inflammation, glycemia, insulin resistance, dyslipidemia, obesity, liver injury (decrease of hepatic enzymes and steatosis and fibrosis). Although microbiota modulators do not play a healing role, they can work as an important adjunct therapy in pathological processes involving NAFLD and its spectrums, either by improving the intestinal barrier or by preventing the formation of toxic metabolites for the liver or by acting on the immune system. 相似文献
256.
Previously, we presented Circus, an integration of Z, CSP, and Morgan’s refinement calculus, with a semantics based on the unifying theories of programming. Circus provides a basis for development of state-rich concurrent systems; it has a formal semantics, a refinement theory, and a development strategy. The design of Circus is our solution to combining data and behavioural specifications. Here, we further explore this issue in the context of object-oriented features. Concretely, we present an object-oriented extension of Circus called OhCircus. We present its syntax, describe its semantics, explain the formalisation of method calls, and discuss our approach to refinement. 相似文献
257.
Marlene Sofia Arcifa Paula Nunes Coelho Lúcia Helena Sampaio da Silva Karina Ocampo Righi-Cavallaro 《河流研究与利用》2023,39(4):661-674
The construction of small hydroelectric plants (SHPs) has increased greatly worldwide, and the impacts of these impoundments can cause changes in the aquatic biota. Here, we investigated the ecological attributes (abundance, richness, and species diversity) of three communities (phytoplankton, invertebrates in the water column, and benthos) and the functional groups of phytoplankton, before and after the construction of five SHPs in an Amazonian river. The communities were sampled at two sites, one upstream and another downstream of each dam or construction site, before the dam closure. The dam did not change the limnological factors, and the acid waters and low electrical conductivity, typical of “cerrado” rivers, were characteristic of both the pre- and post-dam phases. For aquatic communities, the phytoplankton abundance increased and the diversity of groups decreased in the post-dam phase. Regarding the morphology-based functional groups (MBFG), there was an increase in groups I (small algae with a high surface/volume ratio) and V (phytoflagellates), with a reduction in groups VI (diatoms) and VII (large mucilaginous colonies) in the post-dam phase. The relative abundance of zooplankton species increased in the post-dam phase, and the opposite was observed for the benthic community, with reductions in abundance, richness, and group diversity in the post-dam phase. The structure of the three communities differed between the pre- and post-dam phases, but no difference in communities' similarity was observed between the upstream and downstream sites in both phases. The results show that the change in hydrodynamics, from lotic to semi-lentic, in the reservoirs of the SHPs, was the main driving force for the alterations in the three communities. For phytoplankton, SHPs are favorable in the sense of decreasing the incidence of algal blooms, particularly of cyanobacteria. 相似文献
258.
Glória Maria Guizellini Elizabeth Aparecida Ferraz Da Silva Torres Rosana Aparecida Manólio Soares Freitas Tatiana Saldanha Alexandra Christine Helena Frankland Sawaya Ormindo Domingues Gamallo Maiara Jurema Soares Vanessa Sales de Oliveira Geni Rodrigues Sampaio 《Journal of food science》2020,85(8):2416-2426
259.
Paula Gonçalves Carla Gonçalves Patrícia H. Brito José Paulo Sampaio 《Yeast (Chichester, England)》2020,37(4):313-320
The Wickerhamiella and Starmerella genera form a clade (W/S clade) that branches close to Yarrowia lipolytica in the Saccharomycotina species tree. It comprises approximately 90 recognized species and 50 putative new species not formally described yet. The large majority of the members of the W/S clade are ecologically associated with flowers and floricolous insects. Many species exhibit unusual metabolic traits, like fructophily and the production of sophorolipids, which are glycolipids that can be used as environmentally friendly biosurfactants. Genomic data have not only firmly established the W/S clade but have also revealed a tumultuous evolution of metabolism marked by losses and gains of important metabolic pathways, among which alcoholic fermentation. Possibly the most surprising finding brought to light by comparative genomics concerned the large number of genes acquired by some species of the W/S clade from bacteria through horizontal gene transfer, many of which were shown to be functional in their new setting. This was facilitated by the genetic tractability of one species in the clade, Starmerella bombicola, which is used for the industrial production of sophorolipids. We suggest that high-density coverage of genome sequencing in this clade, combined with the possibility to conduct molecular genetics experiments in at least one species, has the potential to set the stage for yet more exciting discoveries concerning the evolution of yeast metabolism. 相似文献
260.
de Jesus Marco Antonio Sampaio Aguiar Dutra Ana Regina de Cirani Claudia Brito Silva Jesus Katia Regina Evaristo Neto Ruy Castro Sobrosa Guerra José Baltazar Andrade 《Clean Technologies and Environmental Policy》2022,24(3):931-948
Clean Technologies and Environmental Policy - Eco-innovations are innovations capable of helping to reduce the environmental impacts of production processes. In this sense, the adoption of models... 相似文献