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The current energy demand requires new energy sources. The use of biomass is an attractive option. In this work, the combustion thermal behaviour and kinetic of custard apple (Annona cherimola) crop remains derived from different plot fertilisation conditions (organic and inorganic) were studied. Thermogravimetry procedures were applied to seeds and wood under four heating rates (5, 10, 20 and 40 °C/min). Iso-conversional methods (Friedman, Flynn–Wall–Ozawa and Kissinger–Akahira–Sunose) were used to determine the activation energy and the frequency factor. Fuel results showed a higher high heating value for seeds (~ 24.78 MJ/mol) when compared with wood (~ 19.33 MJ/mol). Thermogravimetric profiles denoted that, while seed samples were only affected by heating ramps, pruning remains were also influenced by the type of fertiliser. Organic fertiliser was responsible for higher maximum values on the second decomposition peak for wood samples, at 20 and 40 °C/min (56.78%/min and 23.03%/min). Kinetic indexes were also notably influenced by the fertiliser nature. Organic manure reduced the average activation energy results, being more perceptible in seeds (135.51–172.32 kJ/mol) than wood (140.32–144.43 kJ/mol). Hence, it is proven that the type of fertilisation affects the thermal behaviour of custard apple residues. [ABSTRACT FROM AUTHOR]

Trehalose is a common energy reservoir, and its accumulation results in osmotic protection. This sugar can accumulate through its synthesis or slow degradation of the reservoir by trehalase enzymes. Saccharomyces cerevisiae contains two neutral trehalases, NTH1 and NTH2, responsible for 75% and 25% of the enzymatic metabolism. We were interested in the loss-of-function of both enzymes with CRISPR/Cas9. The later NTH2 was of great importance since it is responsible for minor metabolic degradation of this sugar. It was believed that losing its functionality results in limited osmotic protection. We constructed an osmotolerant superior yeast capable of growing in 0.85 M NaCl after independent nth21271_1272delTA mutation by CRISPR/Cas9 technology, compared with nth1 893_894insT and wild type. We suggest that this yeast model could give clues to breeding commercial yeast resulting in non-GMO salinity-tolerant strains. [ABSTRACT FROM AUTHOR]

The present study shows the development of a novel sonochemical synthesis pathway of sub-15 nm silver nanoparticles (AgNPs) with quasi-spherical shape and high stability in aqueous suspension. Different analytical techniques such as on-line UV–Vis spectroscopy, Atomic Force Microscopy (AFM), and Transmission Electron Microscopy (TEM) were complementarily used to characterize the evolution of the properties of AgNPs synthesized with this new route. Furthermore, different centrifugation conditions were studied to establish a practical, simple and straightforward purification method. Particle size was determined by TEM employing two different deposition methods, showing that purified AgNPs have a size of 8.1 nm ± 2.4 nm with a narrow dispersion of the size distribution (95% coverage interval from 3.4 to 13 nm). Critical information of the shape and crystalline structure of these sub-15 nm AgNPs, provided by shape descriptors (circularity and roundness) using TEM and high resolution (HR)-TEM measurements, confirmed the generation of AgNPs with quasi-spherical shapes with certain twin-fault particles promoted by the high energy of the ultrasonic treatment. Elemental analysis by TEM-EDS confirmed the high purity of the sub-15 nm AgNPs, consisting solely of Ag. At the optical level, these AgNPs showed a bandgap energy of (2.795 ± 0.002) eV. Finally, the evaluation of the effects of ultraviolet radiation (UVC: 254 nm and UVA: 365 nm) and storage temperature on the spectral stability revealed high stability of the optical properties and subsequently dimensional properties of sub-15 nm AgNPs in the short-term (600 min) and long-term (24 weeks). [ABSTRACT FROM AUTHOR]

Energy derived from biomass is, nowadays, one of the most attractive options to mitigate fossil fuel use. In this study, an organically fertilized poplar plot was employed. The goals of this work were, in the first place, to analyze the thermal behavior of the samples considering three thermal processes: combustion, gasification, and pyrolysis to, finally, try to determine the influence of the poplar clone and the subscriber type about this parameter. For these purposes, thermogravimetric analysis (TGA) together with kinetic parameters and thermal indexes was used. In the same way, fuel properties were determined. Hence, having average higher heating value around 20 MJ/kg and other accurate properties, poplar samples were considered as a fuel with optimal properties. TGA profiles were different for the thermal processes compared. Four different emission stages appeared for both combustion and gasification (moisture, hemicellulose, cellulose, and lignin). However, pyrolysis profiles showed a different pattern. Thermal index results were higher for the combustion than for the rest of the processes. [ABSTRACT FROM AUTHOR]

Copyright of Cirugía y Cirujanos is the property of Publicidad Permanyer SLU and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Renewable energies can play an important role reversing the current fossil fuels dependence. Among these, biomass is finding more uses consolidating itself as the energy of the future. Current trend is focused on the manufacture of new blends able to achieve a better use of this biomass. The aim of this paper was to assess the potential as fuel of a series of blends consisting of wheat straw and poplar wood fertilized in organic way. Different poplar clones were fertilized with two organic amendments derived from sewage plants. Thus, the effect of clones and fertilization on the thermal behavior of the blends was studied. For this purpose, fuel and thermogravimetric analysis as well as combustion characteristic indexes were used. Results denoted acceptable fuel analysis values. Thermogravimetric profiles showed three mass losses related to volatiles (550 K and 650 K) and char (700 K) liberation. The greatest mass release for blends occurred for the first stage. In particular, the blend consisting of AF8 poplar clone without fertilizer together with straw was the one that experienced this greater release. In the same way, thermal indexes warned of better thermal behavior when fertilizer was not applied; being, again, the blend mentioned above, the one that achieved the best indexes values. Thus, fertilization decreased the thermal performance of wheat straw–poplar wood blends. [ABSTRACT FROM AUTHOR]

This work aimed to investigate thermal decomposition of microalgae throughout the different culture stages. For this purpose, Chlorella sorokiniana was cultured in photobioreactors, and microalgae biomass was sampled at different days throughout the development of the culture. The aim was to analyze the energetic value of this biomass by thermogravimetric analysis as well as to calculate combustion characteristic indexes during the different culture stages. In all cases, thermal decomposition of microalgae biomass during combustion denoted two stages. The first one encompassed the carbohydrates and proteins decomposition and the breakdown of hydrocarbon chains of fatty acids, whereas the second step was closely related to the combustion of the formed char. Fuel composition analysis denoted a microalgae HHV value quite similar to that of Poplar (considered as an energy crop) biomass and slightly higher than published values for herbaceous biomass. In relation with the culture stages, a better combustion performance was found (higher thermal indexes as well as higher DTGmax values) for microalgae biomass sampled at days 19 and 21. These results point to the importance of the culture stage for the thermal valorization of microalgae biomass. [ABSTRACT FROM AUTHOR]

Microalgae are aquatic photosynthetic prokaryotic or eukaryotic microorganisms which cultivation for the fixation of CO2 and the production of biofuels has received large attention. However, the sustainable development of an algal biorefinery is still a challenge. In this context, the valorization of microalgae biomass for a wastewater adsorptive treatment may be an option to explore. Recently, the presence of emerging contaminants (ECs) in natural waters and the associated risks have led to a great concern, especially in the case of pharmaceuticals. In the present work, the elimination of paracetamol from water by biosorption onto microalgae, namely Synechocystis sp., has been studied. Kinetic and equilibrium parameters have been determined and compared with those obtained when using a commercial activated carbon under the same experimental conditions. Although the adsorption kinetics are very similar onto both materials, at the equilibrium, the Langmuir maximum capacity of the activated carbon (278 mg g-1) is five times higher than that of Synechocystis sp. (53 mg g-1). In any case, it must be considered that the utilization of microalgae may be considered an environmentally friendly process with important associated savings. [ABSTRACT FROM AUTHOR]

Energy valorization of rice straw is possible by thermal conversion. The aim of this paper was to study the emissions throughout heating of rice straw under seven different atmospheres (simulating combustion, gasification and pyrolysis). For this purpose, combustion, gasification and pyrolysis of rice straw were studied by simultaneous TG/MS dynamic runs at 15 °C min. Results showed that a partially inert atmosphere is more advisable from an environmental point of view due to the lower emission of contaminants. [ABSTRACT FROM AUTHOR]

This work demonstrates that photochemical doping of CVD-grown graphene can be easily achieved using photoacid (PAG) and photobase (PBG) generators such as triphenylsulfonium perfluoro-1-butanesufonate (TPS-Nf) and 2-nitrobenzyl N-cyclohexylcarbamate (NBC). The TPS-Nf ionic onium salt photoacid generator does not noticeably dope or alter the electrical properties of graphene when coated onto the graphene surface, but is very effective at inducing p-doping of graphene upon exposure of the PAG-coated graphene sample. Likewise, the neutral NBC photobase generator does not significantly affect the electrical properties of graphene when coated, but upon exposure to ultraviolet light produces a free amine, which induces n-doping of the graphene. Electrical measurements show that the doping concentration can be modulated by controlling the deep ultraviolet (DUV) light exposure dose delivered to the sample. The interaction between both dopants and graphene is also investigated. The photochemical doping process is able to tune the work function of the single-layer graphene samples used in this work from 3.4 eV to 5.3 eV. Finally, a p-n junction is fabricated and analyzed, showing that it is possible to control the position of the two current minima (two Dirac points) in the ambipolar p-n junction. [ABSTRACT FROM AUTHOR]

The role of work function and thermodynamic selectivity of hole collecting contacts on the origin of open circuit voltage (VOC) in bulk heterojunction organic photovoltaics is examined for poly(N-9′-heptadecanyl-2,7-carbazole-alt-5,5-(4′,7′-di-2-thienyl-2′,1′,3′-benzothiadiazole) (PCDTBT) and [6,6]-phenyl-C71 butyric acid methyl ester (PC71BM) solar cells. In the absence of a charge selective, electron blocking contact, systematic variation of the work function of the contact directly dictates the VOC, as defined by the energetic separation between the relative Fermi levels for holes and electrons, with little change in the observed dark saturation current, J0. Improving the charge selectivity of the contact through an increased barrier to electron injection from the fullerene in the blend into the hole contact results in a decreased reverse saturation current (decreased J0 and increased shunt resistance, RSH) and improved VOC. Based on these observations, we provide a set of contact design criteria for tuning the VOC in bulk heterojunction organic photovoltaics. [ABSTRACT FROM AUTHOR]

Copyright of Revista CES Salud Pública is the property of Universidad CES and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Pollutants resulting from domestic combustion would have harmful effects on public health, causing disturbances in the atmosphere chemistry and the climate. In this work, the emissions from the combustion of pellets made of 80% poplar (organically fertilized) and 20% cereal straw (Triticum aestivum) have been analysed. Poplar wood from I-214 and AF-8 clones was obtained from fertilized and non-fertilized plots (CONTROL). Dairy wastewater treatment (MUD) and dehydrated sewage sludge (BIOSOLIDS) were the fertilizers employed. BIOSOLIDS-I214 pellets had lower quality standards, so its combustion was omitted. A flue gas sample was sampled together with the particles emitted. The I-214 MUD sample had the highest emitted CO value (1505 mg/MJ). Regarding HCl emission factors, there was a homogeneity in the results linked with the Cl content present in the raw material. A higher particle emission was associated with pellets with higher ash content. Particles were composed mainly for elemental carbon (26–80 mg/MJ), except I-214 MUD. I-214 pellets had the indicators of incomplete combustion and, therefore, major contaminants emission and major environmental impact. Thus, both the poplar clone and the organic fertilizer influenced the parameters and emissions analysed. Therefore, special attention must be paid to both characteristics. [ABSTRACT FROM AUTHOR]

Fluorination of graphene has emerged as an attractive approach toward manipulating its physical, chemical, and electronic properties. To this end, we have demonstrated the viability of sulfur hexafluoride plasmas to fluorinate graphene as a safer alternative to the commonly reported techniques of fluorination that include exposures to fluorine and xenon difluoride gas. Incorporation of fluorine moieties on graphene after SF6 plasma-treatment was confirmed by x-ray photoelectron spectroscopy. Modifications in the valence band states of graphene after plasma-treatment were characterized by ultraviolet photoelectron spectroscopy. Increase in work function of plasma-treated graphene demonstrates the ability of plasma-assisted fluorination to modify the electron emission characteristics of graphene. Raman spectroscopy reveals that the majority of carbon atoms in graphene retain their sp2 hybridization after the plasma-treatment. [ABSTRACT FROM AUTHOR]

An abstract of the article "Duration of Antiretroviral Regimens in Treatment Experienced Patients in Clinical Practice," by Vicente Escudero Vilaplana, Sergio Plata Paniagua, Nicolas Trovato Lopez, Isabel Castillo Romera, Arantza Ais Larisgoitia, Jose Maria Bellon Cano and Maria Sanjurjo Saez is presented.