Solvent Effect on Electrochemical CO₂ Reduction Reaction on Nanostructured Copper Electrodes

The electrochemical reduction of CO2 (CO2RR) is a sustainable alternative for producing fuels and chemicals, although the production of highly desired hydrocarbons is still a challenge due to the higher overpotential requirement in combination with the competitive hydrogen evolution reaction (HER). Tailoring the electrolyte composition is a possible strategy to favor the CO2RR over the HER. In this work we studied the solvent effect on the CO2RR on a nanostructured Cu electrode in acetonitrile solvent with different amounts of water. Similar to what has been observed for aqueous media, our online gas chromatography results showed that CO2RR in acetonitrile solvent is also structure-dependent, since nanocube-covered copper (CuNC) was the only surface (in comparison to polycrystalline Cu) capable of producing a detectable amount of ethylene (10% FE), provided there is enough water present in the electrolyte (>500 mM). In situ Fourier Transform Infrared (FTIR) spectroscopy showed that in acetonitrile solvent the presence of CO2 strongly inhibits HER by driving away water from the interface. CO is by far the main product of CO2RR in acetonitrile (>85% Faradaic efficiency), but adsorbed CO is not detected. This suggests that in acetonitrile media CO adsorption is inhibited compared to aqueous media. Remarkably, the addition of water to acetonitrile has little quantitative and almost no qualitative effect on the activity and selectivity of the CO2RR. This indicates that water is not strongly involved in the rate-determining step of the CO2RR in acetonitrile. Only at the highest water concentrations and at the CuNC surface, the CO coverage becomes high enough that a small amount of C2+ product is formed

Modelos acoplados do IPCC-AR4 e o gradiente meridional de temperatua da superficie do mar no atlântico tropical : relaçoes com a precipitaçao no norte do nordeste do Brasil

Este artigo mostra como três modelos acoplados do Intergovernmental on Panel Climate Change - (IPCC-AR4), o FGOALS1. 0G – LASG do Institute of Atmospheric Physics of China, o GISSER da National Aeronautics Space Admnistration (NASA) e o GFDL_CM2 da National Oceanic and Atmospheric Administration (NOAA), simularam a variabilidade do gradiente meridional de Temperatura da Superfície do Mar (TSM), entre os meses de fevereiro a maio, no Atlântico Tropical (1901-1999). A precipitação durante a estação chuvosa (fevereiro a maio) no setor norte do Nordeste do Brasil (NEB) foi também analisada pelos três modelos e comparada com as observações. Os modelos GISSER e FGOALS1.0G mostraram melhor desempenho na simulação do sinal do gradiente meridional de TSM no Atlântico Tropical para o período de 1901 a 1999. Destaca-se que os modelos apresentaram um melhor desempenho na simulação da tendência decadal, conseguindo explicar entre 50% a 80% da variabilidade do gradiente, com a TSM do setor sul sendo mais bem simulada

Expanded Bed Adsorption Of Bromelain (e.c. 3.4.22.33) From Ananas Comosus Crude Extract

This work focuses on the adsorption of Bromelain in expanded bed conditions, such as the adsorption kinetics parameters. The adsorption kinetics parameters showed that after 40 minutes equilibrium was achieved and maximum adsorption capacity was 6.11 U per resin mL. However, the maximum adsorption capacity was only determined by measuring the adsorption isotherm. Only by the Langmuir model the maximum adsorption capacity, Qm, and dissociation constant, kd, values could be estimated as 9.18 U/mL and 0.591, respectively, at 25°C and 0.1 mol/L phosphate buffer pH 7.5. A column made of glass with an inner diameter of 1 cm was used for the expanded bed adsorption (EBA). The residence time was reduced 10 fold by increasing the expansion degree 2.5 times; nonetheless, the plate number (N) value was reduced only 2 fold. After adsorption, the bromelain was eluted in packed bed mode, with a downward flow. The purification factor was about 13 fold and the total protein was reduced 4 fold. 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Progr, 17, pp. 1128-1136Gaspani, L., Limiroli, E., Ferrario, P., Bianchi, M., In vivo and in vitro effects of bromelain on PGE(2) and SP concentrations in the inflammatory exudate in rats (2002) Pharmacology, 65, pp. 83-86Haq, S.K., Rasheedi, S., Khan, R.H., Characterization of a partially folded intermediate of stem bromelain at low pH (2002) Eur. J. Biochem, 269, pp. 47-52Harrach, T., Eckert, K., Maurer, H.R., Machleidt, I., Machleidt, W., Nuck, R., Isolation and characterization of two forms of an acidic bromelain stem proteinase (1998) J. Protein Chem, 17, pp. 351-361Hatano, K., Sawano, Y., Tanokura, M., Structure-function relationship of bromelain isoinhibitors from pineapple stem (2002) Biol. Chem, 383, pp. 1151-1156Hatano, K., Tanokura, M., Takahashi, K., The amino acid sequences of isoforms of the bromelain inhibitor from pineapple stem (1998) J. 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Resonance fluorescence from a telecom-wavelength quantum dot

© 2016 Author(s).We report on resonance fluorescence from a single quantum dot emitting at telecom wavelengths. We perform high-resolution spectroscopy and observe the Mollow triplet in the Rabi regime - a hallmark of resonance fluorescence. The measured resonance-fluorescence spectra allow us to rule out pure dephasing as a significant decoherence mechanism in these quantum dots. Combined with numerical simulations, the experimental results provide robust characterisation of charge noise in the environment of the quantum dot. Resonant control of the quantum dot opens up new possibilities for the on-demand generation of indistinguishable single photons at telecom wavelengths as well as quantum optics experiments and direct manipulation of solid-state qubits in telecom-wavelength quantum dots

Exopolysaccharides, proteins and lipids in Pleurotus pulmonarius submerged culture using different carbon sources

AbstractFor many years mushrooms have been consumed and appreciated by their nutritional value, and medicinal properties. The traditional mushroom cultivation takes too long and the macrofungi biotechnology has not been explored in its full potential yet. The goal of this work was to observe if different carbon sources could improve the yield and diversify fungi nutrient composition in submerged culture.Pleurotus pulmonarius mycelia and exopolysacharide productions were evaluated using glucose, galactose, xylose and arabinose. The mycelia yield varied depending on the culture medium, and galactose showed to be the best carbon source to produce EPS. Samples that showed the highest protein contents were grown with xylose (19.44%) and arabinose (26.05%). Furthermore, the biomass cultivated with these carbohydrates and with galactose showed five essential amino acids. All cultured biomass showed low lipid contents (∼1%), being composed mainly of unsaturated fatty acids. All EPS fractions showed as main structures glucans and mannogalactans

Spatial analysis of leptospirosis and toxoplasmosis seroprevalence in the canine population in an area of socioeconomic and environmental vulnerability

ABSTRACT Leptospirosis and toxoplasmosis are zoonoses of occupational character that are spread worldwide, mainly in tropical and socioeconomically vulnerable areas. Both diseases have vertebrate hosts, which spread the infectious agent to the environment and are potentially infectious to humans and can progress to fatal cases. The present study reinforces the importance of One Health for the control and prophylaxis of leptospirosis and toxoplasmosis using sentinel animals in areas of socioeconomic vulnerability based on a serological study. A total of 336 blood samples were obtained from the canine population of the urban district, which has high rates of poverty and sanitation. The results were analyzed based on seroreactivity animals and georeferencing by kernel spatial mapping. A total of 43.3% (52/120) of the animals were seroreagents for anti-Leptospira spp., with a predominance of Canicola (35/52 = 67.3%) and Pyrogenes (5/52 = 9.6%), while 52.97% (178/336) of the dogs were seroreactive for anti-Toxoplasma gondii. The presence of seroreagent dogs for both zoonosis alert to the inadequate hygienic-sanitary conditions of the studied region, and highlight the importance of a survey of the social, economic and environmental structure to identify factors related to the links in the epidemiological chain of pathogen transmission and necessary corrective actions

Bifidobacterium animalis subsp lactis HN019 presents antimicrobial potential against periodontopathogens and modulates the immunological response of oral mucosa in periodontitis patients

Objective To evaluate the effects of Bifidobacterium animalis subsp. lactis HN019 (HN019) on clinical periodontal parameters (plaque accumulation and gingival bleeding), on immunocompetence of gingival tissues [expression of beta-defensin (BD)-3, toll-like receptor 4 (TLR4), cluster of differentiation(CD)-57 and CD-4], and on immunological properties of saliva (IgA levels) in non-surgical periodontal therapy in generalized chronic periodontitis (GCP) patients. Adhesion to buccal epithelial cells (BEC) and the antimicrobial properties of HN019 were also investigated. Materials and methods Thirty patients were recruited and monitored clinically at baseline (before scaling and root planing—SRP) and after 30 and 90 days. Patients were randomly assigned to Test (SRP+Probiotic, n = 15) or Control (SRP+Placebo, n = 15) group. Probiotic lozenges were used for 30 days. Gingival tissues and saliva were immunologically analyzed. The adhesion of HN019 with or without Porphyromonas gingivalis in BEC and its antimicrobial properties were investigated in in vitro assays. Data were statistically analyzed (p</p