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Technological approaches which enable the effective utilization of CO2 for manufacturing value-added chemicals and fuels can help to solve environmental problems derived from large CO2 emissions associated with the use of fossil fuels. One of the most interesting products that can be synthesized from CO2 is methanol, since it is an industrial commodity used in several chemical products and also an efficient transportation fuel. In this review, we highlight the recent advances in the development of heterogeneous catalysts and processes for the direct hydrogenation of CO2 to methanol. The main efforts focused on the improvement of conventional Cu/ZnO based catalysts and the development of new catalytic systems targeting the specific needs for CO2 to methanol reactions (unfavourable thermodynamics, production of high amount of water and high methanol selectivity under high or full CO2 conversion). Major studies on the development of active and selective catalysts based on thermodynamics, mechanisms, nano-synthesis and catalyst design (active phase, promoters, supports, etc.) are highlighted in this review. Finally, a summary concerning future perspectives on the research and development of efficient heterogeneous catalysts for methanol synthesis from CO2 will be presented.

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The modification of Cu-Zn catalysts with low amount of Al and Ga (Al+Ga = 3%) was investigated and data corresponding to its influence on the decomposition of the calcined precursors and on the nanomorphology and surface concentration of reduced catalysts were presented in this contribution. The data presented here are supplementary material of the catalysts presented in the research article "Structure and activity of Cu/ZnO catalysts co-modified with aluminium and gallium for methanol synthesis" published in Catalysis Today [1].

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The influence of aging of precipitates on the physical and catalytic properties of a copper/zinc oxide-aluminium (Cu/ZnO-Al) catalyst with an optimized composition (low Al concentration, Cu/Zn/Al = 68/29/3) prepared using co-precipitation has been investigated in detail. The change in the structure of precipitates with aging (from amorphous zincian georgeite to crystalline zincian malachite) strongly influences the micro- and nano-structure (Cu and ZnO crystallite size, exposed copper surface area, Cu-ZnO interactions and stability of ZnO) of the final Cu/ZnO-Al catalysts obtained after calcination and reduction of the precipitates. The results of catalytic activity in methanol synthesis from syngas show the higher intrinsic activity of the catalysts derived from aged zincian malachite precipitates as consequence of the increase in the exposed copper surface area and the Cu-ZnO contacts. The stability of catalysts under the reaction conditions was also improved in the catalysts derived from precipitates aged after crystallization of malachite. The catalyst derived from the precipitate removed close to the point of crystallization of malachite shows very poor activity in the methanol synthesis as consequence of its segregated large Cu crystallites in low contact with ZnO derived from the absence of carbonate retention after calcination of the precipitate and the presence of sodium species after conventional washing which favour the strong sintering and crystallization of Cu during reduction.

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Magellanic penguins, Spheniscus magellanicus, are the most abundant penguins living in temperate regions of South America and are good indicators of environmental pollution in the region. Persistent organic pollutants (POPs) were detected in the liver of Magellanic penguins found debilitated or dead on the beaches of Brazil (states of Rio de Janeiro, Sao Paulo, Santa Catarina and Rio Grande do Sul) between 2008 and 2012 as well as in Uruguay and Chile in 2011. Polychlorinated biphenyls (PCBs) were more prevalent than organochlorine pesticides (DDTs ∼ HCB ∼ Drins) and polybrominated diphenyl ethers (PBDEs). Among PCBs, penta-, hexa- and hepta-chlorinated congeners were predominant. Concentrations of POPs were similar between the Pacific and Atlantic penguin populations, except for PCBs, which were relatively higher in the Pacific population. During the study years (2008-2012), large variations were found in organochlorine pesticides and PCBs tended to decline. Overall, the southern portion of South America has low concentrations of POPs, with either a constant trend or evidence of decline.

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Modification of alumina with La-, Ce-, Zr- and Mg-oxides was studied with the aim to use them as supports of bimetallic Pt-Ni catalysts for the steam reforming of ethanol. Activity results showed that modifications of Al2O3 support with the incorporation of La, Ce, Zr or Mg oxides play an essential role in the catalytic behaviour of PtNi catalysts. Bimetallic PtNi catalyst supported on bare Al2O3 showed evolution of the reaction products with time on stream consisting in the increase of C2H4 production with concomitant decrease of CH4 and CO2 production. The addition of Mg or Zr to γ-A1203 did not inhibit the appearance of ethylene but delayed its production. In the case of Ce- or La-supported catalysts, the product selectivities were stable with time-on-stream, with no changes being observed in the product distribution for 24 h. Characterization results showed that La- and Ce-containing supports improves the Pt and Ni metal exposure values. The better stability achieved for Ce and La containing catalysts was inferred to be related with a participation/assistance of lanthanum and cerium entities in the gasification of coke deposits together with a modification of Pt and Ni dispersion which lower the probability of the nucleation of coke precursors on their surfaces.

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This article provides an overview of stroke genetics studies ranging from the candidate gene approach to more recent studies by the genome wide association. It highlights the complexity of stroke owing to its different aetiopathogenic mechanisms, the difficulties in studying its genetic component, and the solutions provided to date. The study emphasises the importance of cooperation between the different centres, whether this takes places occasionally or through the creation of lasting consortiums. This strategy is currently essential to the completion of high-quality scientific studies that allow researchers to gain a better knowledge of the genetic component of stroke as it relates to aetiology, treatment, and prevention.

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This work analyzes the influence of cerium content (6-15 wt%) on a TiO(2) support over the structure and water gas shift (WGS) activity of Pt catalysts. The structural properties of these Pt/Ce-TiO(2) catalysts were characterized by XRD, TEM and XANES. Physicochemical characterization of the catalysts showed differences in the structure and dispersion of Ce entities on the support with Ce loading. For the samples with low ceria content (6 wt%), cerium is deposited on the support in the form of CeO(x) clusters in a highly dispersed state in close interaction with the Ti atoms. The formation of CeO(x) clusters at low Ce-loading on the support facilitates the dispersion of small particles of Pt and improves the reducibility of ceria component at low temperatures. The changes in platinum dispersion and support reducibility with Ce-loading on the TiO(2) support lead to significant differences in the WGS activity. Pt supported on the sample with lower Ce content (6 wt%) shows better activity than those corresponding to catalysts with higher Ce content (15 wt%). Activity measurements coupled with catalysts characterization suggest that the improvement in the reducibility of the support with lower Ce content was associated with the presence of CeO(x) clusters of high reducibility that improve the chemical activity of the oxide-metal interfaces at which the WGS reaction takes place.

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Palladium catalysts supported on gamma-alumina (AN, AS), amorphous silica-alumina (ASA), and beta-zeolite (betaZ) were prepared with the aim to reduce the content of polycyclic aromatic hydrocarbons (PAHs) in diesel fuels. The removal of PAH compounds was evaluated with a model feed (toluene, naphthalene, and dibenzothiophene)that approached the composition of diesel fuel. The catalysts were characterized by N2 adsorption-desorption isotherms, X-ray photoelectron spectroscopy, transmission electron microscopy, temperature-programmed reduction/temperature-programmed oxidation, Fourier transform (FT) IR of absorbed CO, and diffuse reflectance FT spectroscopy of adsorbed NH3. When palladium was supported on ASA instead of AN or betaZ, the intrinsic activity improved considerably. Such behavior is discussed in terms of larger Brønsted acidity and the degree of reduction of the Pd species on Pd/ASA. For the 2.2 Pd/betaZ catalyst, interaction of the Pd clusters with zeolite protons led to formation of Pddelta+ species, which are not active in the hydrogenation of aromatics. All catalysts were resistant to poisoning by S compounds.

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STUDY OBJECTIVES: To test the hypothesis that continuous application of local anesthesia at the contact area between the endotracheal tube cuff and trachea would reduce both the incidence and severity of postoperative sore throat by blocking the tracheal pain receptors with local anesthetic delivered via endotracheal tube (ETT) cuff. DESIGN: Double-blind randomized study. SETTING: University affiliate hospital. PATIENTS: 106 ASA physical status I and II patients. INTERVENTIONS: Patients' ETT cuffs were inflated with either air or lidocaine. The cuffs of the lidocaine group were prefilled with lidocaine for 90 minutes prior to intubation to saturate the cuff membrane. One hour and 24 hours following extubation, patients were asked about the presence and severity of postoperative sore throat. MEASUREMENTS AND MAIN RESULTS: There was no difference between groups in demographics or anesthetic management. The incidence of sore throat was significantly different at the 24-hour evaluation (59% air vs. 32% lidocaine, p = 0.01). Severity of sore throat was significantly worse with air at both evaluation periods (1 hour = 18.7 +/- 27.0 air vs. 7.90 +/- 18.1 lidocaine, p = 0.02; 24 hours = 25.6 +/- 27.5 air vs. 14.5 +/- 24.8 lidocaine, p = 0.03). CONCLUSIONS: Using lidocaine to inflate the ETT cuff decreases the severity of postoperative sore throat at one hour, and both the incidence and severity at 24 hours.

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