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Objective: Combining a macrolide or a fluoroquinolone to beta-lactam regimens in the treatment of patients with moderate to severe community-acquired pneumonia is recommended by the international guidelines. However, the information in patients with bacteraemic pneumococcal pneumonia is limited.Methods: A propensity score technique was used to analyze prospectively collected data from all patients with bacteraemic pneumococcal pneumonia admitted from 2000 to 2015 in our institution, who had received empirical treatment with third-generation cephalosporin in monotherapy or plus macrolide or fluoroquinolone.Results: We included 69 patients in the monotherapy group and 314 in the combination group. After adjustment by PS for receiving monotherapy, 30-day mortality (OR 2.89; 95% CI 1.07-7.84) was significantly higher in monotherapy group. A higher 30-day mortality was observed in monotherapy group in both 1:1 and 1:2 matched samples although it was statistically significant only in 1:2 sample (OR: 3.50 (95% CI 1.03-11.96), P = 0.046).Conclusions: Our study suggests that in bacteraemic pneumococcal pneumonia, empirical therapy with a third-generation cephalosporin plus a macrolide or a fluoroquinolone is associated with a lower mortality rate than beta-lactams in monotherapy. These results support the recommendation of combination therapy in patients requiring admission with moderate to severe disease. [ABSTRACT FROM AUTHOR]

Abstract: The title compounds have been synthesized by a citrate technique. The crystal structure of these materials has been studied at room temperature from high-resolution neutron powder diffraction data. In, Ru, and M=Mn,Fe are distributed at random over the metal sites of a C-M2O3 bixbyite-type structure, space group , with for M=Mn and for M=Fe. It is well known that In2O3 is able to dissolve certain amounts of transition metals but, at ambient pressure, the solubility is rather small, lower than in In2−s M s O3. Here, we describe a substantial incorporation of magnetic transition metals into In2O3 of half of the metal positions (), by simple thermal treatment at temperatures in the 1300–1400 °C range. Although a bond-valence study shows unrealistically low valences for Ru ions, which statistically occupy the metal positions, replacing In, the magnetic properties suggest a valence equilibrium Ru3+/M3+↔Ru4+/M2+. In2RuFeO6 shows antiferromagnetic interactions below , with a very weak ferromagnetism effect at low temperatures. [Copyright &y& Elsevier]

Abstract: The Ca(V0.5Mo0.5)O3 perovskite has been prepared in order to study its potential use as anode in SOFC. The crystal structure has been refined, by neutron powder diffraction, in the orthorhombic Pbnm space group (no. 62). The electrical conductivity values were over 525Scm−1 in the studied temperature range (25–800°C). The sample is stable under reducing working conditions (H2/N2 10:90, 25–900°C). This orthorhombic phase transforms at 500°C in air to the tetragonal I4 1/a scheelite phase. This transition is reversible and, due to the fact that the thermal expansion coefficients of both, the reduced and oxidized phases, are very similar and match well with those of the other cell components ((10–13)×10−6 K−1) this materials are presented as excellent candidates as anodes in SOFCs. [Copyright &y& Elsevier]

Abstract: Temperature dependent X-ray and neutron powder diffraction have been exploited to revisit the structural evolution of SrCoO2.5 brownmillerite-like phase from room temperature to 1200°C, in complement with DTA–TG, conductivity and thermal expansion measurements. Three different polymorphs have been identified: the orthorhombic “O” brownmillerite phase between room temperature and 653°C, the hexagonal “H” phase between 653°C and 920°C, and the cubic perovskite “C” above 920°C, which is transformed again, by cooling, into the “H” phase at 774°C. The metastable “O” brownmillerite phase can only be obtained by quenching in liquid N2 from 1000°C. The refinement of the crystal and magnetic structures of SrCoO2.5 from NPD data collected “in situ” as a function of temperature in an air atmosphere led to define structural details of the very distinct coordination polyhedra present in the different polymorphs, which have been correlated with the transport properties. The conductivity shows little dependence up to 250°C, and it abruptly increases above this temperature, which is concomitant with a contraction of the Co2–O3 bonds of the tetrahedral CoO4 units of the “O” brownmillerite structure at 350°C, suggesting the presence of an insulator-to-metal transition in this structural polymorph. The dramatic reduction of conductivity above 500°C is connected with the transformation to the “H” polymorph, with a complete oxygen sublattice and a face-sharing octahedral framework with a poor 1D electronic conduction. Further heating above 900°C boosts again the conductivity when the sample is entering the cubic perovskite region, characterized by a 3D vertex-sharing network of CoO6 octahedra. The total conductivity displays a maximum value of 150Scm−1 at 900°C and it increases during the cooling run, thus displaying a characteristic metallic behaviour for the “C” phase. This polymorph presents conductivity values substantially above the required 100Scm−1 in solid oxide fuel cells, suggesting that it is a good candidate for cathode materials in energy conversion devices. [Copyright &y& Elsevier]

Abstract: A new material of nominal stoichiometry YGaMnO5 has been prepared in polycrystalline form from citrate precursors followed by thermal treatments under high-oxygen pressure. This compound has been characterized from neutron powder diffraction (NPD) data and magnetic measurements. For comparison, the parent compound YMn2O5 has also been synthesized and its crystal structure refined by NPD data. The new oxide has an actual stoichiometry YGa1−x Mn1+x O5 (x =0.23), determined by NPD, showing an important cationic disorder between both metal sites; it is orthorhombic, Pbam (SG), and its crystal structure contains chains of Mn4+O6 edge-sharing octahedra, linked together by Ga3+O5 pyramids and YO8 units. With respect to YMn2O5, containing axially elongated MnO5 pyramids due to the Jahn–Teller effect of Mn3+ cations, the GaO5 pyramidal units in YGa0.77Mn1.23O5 are substantially flattened. This compound has a paramagnetic behaviour with two weak anomalies at about 50K and 350K. The magnetic structures, studied at 1.4K and 100K show a ferromagnetic coupling along the chains of MnO6 octahedra. [Copyright &y& Elsevier]

Abstract: The use of pyrochlore oxides as solid-oxide fuel cells (SOFC) cathodes is a promising and rather unexplored alternative. The presence of some cationic disorder in pyrochlores promotes the Frenkel-defect formation responsible of a high-ionic conductivity in these compounds. Moreover, the use of the suitable transition metals at the B position gives rise to an adequate electronic conductivity constituting disordered pyrochlores as mixed, ionic–electronic conductors. In this work, we have synthesized and characterized a new family of pyrochlore oxides with the formula R2MnRuO7 (R=Tb, Dy, Ho, Er, Tm, Yb, Lu and Y) using the smallest rare-earth cations in order to promote disorder in the crystal lattice. Polycrystalline samples were prepared by a soft chemistry procedure involving citrates of the different metal ions, followed by thermal treatments in air or O2 pressure. They are all cubic, space group . The Rietveld-refinement from neutron powder diffraction data at room-temperature evidences that the cation disorder (distribution of Mn between A and B positions) increases when the size of R decreases. This disorder is accompanied by an increment of the oxygen-vacancy concentration due to the reduction of Mn4+ at the B position to Mn2+ at the A position. The obtained compounds display a semiconductor-like behavior with a maximum conductivity of 8.9Scm−1 for Er2MnRuO7 at 900°C. Moreover, the measured thermal expansion coefficients are in the range of 9.8–10.7×10−6 K−1 between 100 and 900°C that perfectly match those of the usual electrolytes, YSZ, LSGM or CGO. The obtained results present the R2MnRuO7 pyrochlores as alternative cathodes for IT-SOFCs. [Copyright &y& Elsevier]

Abstract: The SrCo1−x Sb x O3−δ (x =0.05, 0.1, 0.15 and 0.2) system was tested as possible cathode for solid oxide fuel cells (SOFCs). X-ray diffraction results show the stabilization of a tetragonal P4/mmm structure with Sb contents between x =0.05 and x =0.15. At x =0.2 a phase transition takes place and the material is defined in the cubic Pm-3m space group. In comparison with the undoped hexagonal SrCoO3 phase, the obtained compounds present high thermal stability without abrupt changes in the expansion coefficient. In addition, a great enhancement of the electrical conductivity was observed at low and intermediate temperatures (T ≤800°C). The sample with x =0.05 displays the highest conductivity value that reaches 500Scm−1 at 400°C and is over 160Scm−1 in the usual working conditions of a cathode in SOFC (650–900°C). Moreover, the impedance spectra of the SrCo1−x Sb x O3−δ /Ce0.8Nd0.2O2−δ /SrCo1−x Sb x O3−δ (x ≥0.05) symmetrical cells reveal polarization resistances below 0.09Ωcm2 at 750°C which are much smaller than that displayed by the pristine SrCoO3−δ sample. The composition with x =0.05 shows the lowest ASR values ranging from 0.009 to 0.23Ωcm2 in the 900–600°C temperature interval with an activation energy of 0.82eV. [Copyright &y& Elsevier]