Search

Orally administered dimethyl fumarate (DMF) presents gastrointestinal adverse effects, such as pain and diarrhea, in addition to flushing and lymphopenia.Solid lipid nanoparticles (SLNs) with DMF were developed for subcutaneous administration.DMF-incorporated SLNs and free DMF were tested in mice induced with experimental autoimmune encephalomyelitis (EAE).Preventive treatment of free or incorporated DMF were able to reduce the EAE clinical scores, increase the weight of the animals, reduce the lesion area (demyelination and infiltration), reduce microglial fluorescence intensity and reduce the number of microglial cells and astrocytes, when compared to untreated EAE animals. Groups that received DMF had reduced numbers of T cells, B cells and natural killer (NK) cells in the blood, when compared to the non-induced group.DMF incorporated in SLNs was as effective as free DMF in reducing the clinical scores of the animals, but with reduced administrations when given subcutaneously. In addition, SLN-DMF preventive treatment partially prevented a reduction in the percentages of T and B cells, in the blood, when compared to preventive treatment with free DMF (oral), which suggests reduction of lymphopenia.

A simple, inexpensive, highly sensitive, selective novel electrochemical method was developed for simultaneous quantification of the fungicides thiram and carbendazim in samples of honey, fresh grape juice, and an agricultural formulation using a carbon paste electrode modified with recrystallized zeolite. Zeolite was characterized by TG-DSC, XRD, FT-IR, and SEM-EDS before and after recrystallization treatment. The electrodes were electrochemically characterized using cyclic voltammetry, square-wave voltammetry, and electrochemical impedance spectroscopy. Electrode area, standard heterogeneous rate constant, and double-layer capacitance were the electrochemical variables investigated. Recrystallized zeolite had a strong influence on these variables. Development of the method for simultaneous thiram and carbendazim quantification involved optimizing instrumental parameters (frequency, amplitude, and potential step) and experimental parameters (pH, zeolite content, temperature, and recrystallization time). The oxidation peak current for thiram varied linearly in the concentration range of 0.36–4.99 × 10−7 mol L−1, with limit of detection (LD) of 6.74 × 10−9 mol L−1 and limit of quantification (LQ) of 20.17 × 10−9 mol L−1. For carbendazim, the oxidation peak current varied linearly in the concentration range of 0.10–2.35 × 10−6 mol L−1, with LD and LQ of 3.51 × 10−9 and 11.71 × 10−9 mol L−1, respectively. Thiram and carbendazim recovery experiments were performed by adding known amounts of these fungicides to samples of honey and grape juice, yielding recovery rates in the 98.85–101.15% range. In the agricultural formulation, the concentrations measured with the new method were close to those specified on the label, with deviations of below 1.1%. No thiram or carbendazim were found in the grape juice and honey samples. The results demonstrated the method's feasibility for quantifying both compounds simultaneously in these samples.

Pt nanoclusters with Pt porous dendritic structures on top (high porosity materials) were electrodeposited at a low overpotential onto glassy carbon (GC) electrodes modified with graphite (GR), multiwalled carbon nanotubes (MWCNT), graphene oxide (GO), graphene oxide nanoribbons (GONR), chemically converted graphene (CCG), and graphene nanoribbons (GNR). The electrochemical profiles of these materials were investigated using cyclic voltammetry and microgravimetry (electrochemical quartz microbalance). Their electrocatalytic activity towards the oxygen-reduction reaction (ORR) was studied employing hydrodynamic cyclic voltammetry. Physical characterization of the samples was based on transmission electron microscopy (TEM), scanning electron microscope (SEM), atomic force microscopy (AFM), and energy-dispersive X-ray microanalysis (EDX). Pt electrocatalysts electrodeposited onto CCG and GNR exhibited high electrocatalytic activity towards ORR when compared with commercial Pt (10 wt.%) on carbon and high stability after 10 000 potential scans, suggesting the possibility of applying these catalysts to acid fuel cells—viable even in economic terms, as very low amounts of finely dispersed Pt per cm 2 onto thin CCG or GNR films were required to produce the electrocatalysts. GC electrodes modified with Pt electrodeposited onto GR, MWCNT, GO, or GONR exhibited poor electrocatalytic activity.

Anodes and cathodes of fuel cells are usually composed of metallic nanoparticles (NPs) dispersed on carbon, in order to increase their active area. Since the degradation of the catalyst affects the performance of the fuel cells, understanding the stability of its components is pivotal to make these systems more reliable. As such, graphene sheets and carbon nanotubes have been employed as alternative supports to improve the stability of anodes in fuel cells. In this context, we have used polyvinylpyrrolidone (PVP) combined with a one-step chemical reduction induced by ethylene glycol to synthesize Pd NPs dispersed on chemically converted graphene (CCG). We compared the electrochemical stability of Pd NPs supported on carbon black (C), multi-walled carbon nanotubes (MWCNTs) and CCG. MWCNTs and CCG make Pd NPs electrochemically more stable than carbon black. Pd/CCG catalysts are more stable than Pd/MWCNTs during the first potential cycles, while Pd/MWCNTs showed a higher long-term stability. These results allow us to consider a competition between agglomeration of NPs and degradation of the support, where the agglomeration seems to be limited by the available surface area of the support. Fil: Martins, Cauê A.. Universidade Federal do Mato Grosso do Sul; Brasil. Universidade Federal da Grande Dourados; Brasil Fil: Fernández, Pablo Sebastián. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - La Plata. Instituto de Investigaciones Fisicoquímicas Teóricas y Aplicadas. Universidad Nacional de La Plata. Facultad de Ciencias Exactas. Instituto de Investigaciones Fisicoquímicas Teóricas y Aplicadas; Argentina Fil: De Lima, Fabio. Universidade Federal do Mato Grosso do Sul; Brasil Fil: Troiani, Horacio Esteban. Comisión Nacional de Energía Atómica. Gerencia del Area de Investigación y Aplicaciones No Nucleares. Gerencia de Física (Centro Atómico Bariloche); Argentina Fil: Martins, María Elisa. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - La Plata. Instituto de Investigaciones Fisicoquímicas Teóricas y Aplicadas. Universidad Nacional de La Plata. Facultad de Ciencias Exactas. Instituto de Investigaciones Fisicoquímicas Teóricas y Aplicadas; Argentina Fil: Arenillas de la Puente, Ana. Instituto Nacional del Carbón; España. Consejo Superior de Investigaciones Científicas; España Fil: Gilberto, Maia. Universidade Federal do Mato Grosso do Sul; Brasil Fil: Camara, Giuseppe A.. Universidade Federal do Mato Grosso do Sul; Brasil

This paper discusses four algorithms for detecting anomalies in logs of process aware systems. One of the algorithms only marks as potential anomalies traces that are infrequent in the log. The other three algorithms: threshold, iterative and sampling are based on mining a process model from the log, or a subset of it. The algorithms were evaluated on a set of 1500 artificial logs, with different profiles on the number of anomalous traces and the number of times each anomalous traces was present in the log. The sampling algorithm proved to be the most effective solution. We also applied the algorithm to a real log, and compared the resulting detected anomalous traces with the ones detected by a different procedure that relies on manual choices.

A novel pequi fruit ( Caryocar brasiliense Camb.) homogenate source of polyphenol oxidase was obtained and immobilized in chitosan crosslinked with cyanuric chloride (CHcych-PPO). A biosensor was developed and used for the square-wave voltammetric determination of thiodicarb. Several parameters were investigated to evaluate the performance of this biosensor in the presence of hydroquinone and thiodicarb. The best response was obtained using 70:20:10% (w/w/w) of graphite powder:Nujol:CHcych-PPO, 250 U mL −1 of PPO and phosphate buffer solution (0.1 M; pH 7.0) with frequency, pulse amplitude and scan increment of 10 Hz, 150 mV, and 15 mV, respectively. Under optimized operational conditions the thiodicarb concentration was linear in the range of 3.75 × 10 −7 to 2.23 × 10 −6 M with a detection limit of 1.58 × 10 −7 M. The biosensor was applied in the determination of thiodicarb in fresh fruit and vegetable samples and the results compared with those obtained using high-performance liquid chromatography.

This paper reports the integrated application of petrographic and Sm–Nd isotopic analyses for studying the provenance of the Neoproterozoic Marica Formation, southern Brazil. This unit encompasses sedimentary rocks of fluvial and marine affiliations. In the lower fluvial succession, sandstones plot in the “craton interior” and “transitional continental” fields of the QFL diagram. Chemical weathering probably caused the decrease of the 147Sm/144Nd ratios to 0.0826 and 0.0960, consequently lowering originally > 2.0 Ga TDM ages to 1.76 and 1.81 Ga. 143Nd/144Nd ratios are also low (0.511521 to 0.511633), corresponding to negative eNd present-day values (− 21.8 and − 19.6). In the intermediate marine succession, sandstones plot in the “dissected arc” field, reflecting the input of andesitic clasts. Siltstones and shales reveal low 143Nd/144Nd ratios (0.511429 to 0.511710), eNd values of − 18.1 and − 23.6, and TDM ages of 2.16 and 2.37 Ga. Sandstones of the upper fluvial succession have “dissected arc” and “recycled orogen” provenance. 143Nd/144Nd isotopic ratios are also relatively low, from 0.511487 to 0.511560, corresponding to eNd values of − 22.4 and − 21.0 and TDM of 2.07 Ga. A uniform granite–gneissic basement block of Paleoproterozoic age, with subordinate volcanic rocks, is suggested as the main sediment source of the Marica Formation.

Nos últimos vinte anos, nosso serviço recebeu os pacientes com a suspeita de Leucemia Mielóide Aguda (LMA) provenientes de todas as regiões do estado. Entre março de 1980 e dezembro de 1999 analisamos 195 pacientes com idades superior a 12 e inferior a 70 anos, apresentando LMA "de novo" excetuando o subtipo M3. Na década de 80 foram registrados 102 pacientes: 47 homens e 55 mulheres. Destes, 84 receberam quimioterapia de indução com Citarabina e Daunorrubicina (esquema "7+3"), resultando no índice de remissão de 51% (43/84). As médias de sobrevidas livre de doença e global foram dez meses em 35% e 12 meses em 13% respectivamente. De jan/90 a dez/93 houve 41 novos diagnósticos e todos foram submetidos à quimioterapia com esquema "7+3" atingindo a taxa de 66% de remissão. As sobrevidas livre de doença e global foram estatisticamente (p