CaTiO3 and Ca1-3xSmxTiO3: Photoluminescence and morphology as a result of Hydrothermal Microwave Methodology

Calcium titanate (CaTiO3 - CT) and samarium doped calcium titanate (CaTiO3:Sm3+ - CT:Sm) powders in different Sm3+ concentrations (0.5-5.0% molar ratio of Sm3+) were obtained by the Hydrothermal Microwave Methodology at 140 degrees C for 16 min. These crystals were structurally characterized by X-ray diffraction (XRD) and micro-Raman (MR) spectroscopy. Field emission scanning electron microscopy images were employed to observe the shape and size of the crystals. The optical properties were investigated by ultraviolet visible (UV Vis) absorption and photoluminescence (PL) measurements. The XRD indicated structural organization at long range while MR revealed short range order for all undoped and Sm-doped samples. Morphological analysis revealed a new cubic morphology for CT:Sm, presenting an average size of 3.0 mu m. Further, the ultraviolet visible absorption spectra indicated the existence of intermediary energy levels within the band gap. The maximum intensity PL emission occurred due to (4)G(5/2) -> H-6(7/2) and (4)G(5/2) -> H-6(9/2), transitions of Sm3+. CIE chromaticity coordinates of the samples were determined and support these materials are promising candidates for applications as phosphors in the visible orange range. This research concluded that the methodology employed here was responsible for the presence of unusual and interesting properties for these new luminescent materials. (C) 2015 Elsevier Ltd and Techna Group S.r.l. All rights reserved.Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq)Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)INCTMN, LIEC, Chemistry Department, Federal University of São Carlos, P.O. Box 676, 13565-905 São Carlos, SP, BrazilInstituto de Ciência e Engenharia do Mar-Federal University of São Paulo-UNIFESP/Campus Baixada Santista, Av. Alm. Saldanha da Gama, 89 – Ponta da Praia, Santos, SP CEP: 11030-400, BrazilUNIFESP, Federal University of São Paulo, Rua Prof. Artur Riedel, 275, SP, 09972-270 Diadema, SP, BrazilINCTMN, LIEC, Chemistry Institute, State University of São Paulo, UNESP, P.O. Box 355, 14800-900 Araraquara, SP, BrazilInstituto de Ciência e Engenharia do Mar-Federal University of São Paulo-UNIFESP/Campus Baixada Santista, Av. Alm. Saldanha da Gama, 89 – Ponta da Praia, Santos, SP CEP: 11030-400, BrazilUNIFESP, Federal University of São Paulo, Rua Prof. Artur Riedel, 275, SP, 09972-270 Diadema, SP, BrazilCNPq: 573636/2008-7FAPESP: 2008/57872-1FAPESP: 2013/07296-2CNPq: 132320/2012-6Web of Scienc

Gadolinium-doped cerium oxide nanorods: novel active catalysts for ethanol reforming

The gadolinium-doped ceria nanorods (Gd(0.2)Ce(0.8)O(2-x) ) were synthesized by hydrothermal treatment. It was shown that the use of microwave heating during hydrothermal treatment decreases the treatment time required to obtain gadolinium-doped ceria nanorods and that oriented attachment is the dominant mechanism responsible for anisotropic growth. It was clear that Gd(0.2)Ce(0.8)O(2-x) nanorods were more catalytically active than commercial CeO(2) in the ethanol reforming reaction.Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq

Effect of Er3+ ions on the phase formation and properties of In(2)O(3)nanostructures crystallized upon microwave heating

Regular sized nanostructures of indium oxide (In2O3) were homogeneously grown using a facile route, i.e. a microwave-hydrothermal method combined with rapid thermal treatment in a microwave oven. The presence of Er3+ doping plays an important role in controlling the formation of cubic (bcc) and rhombohedral (rh) In2O3 phases. The samples presented broad photoluminescent emission bands in the green-orange region, which were attributed to the recombination of electrons at oxygen vacancies. The photocatalytic activities of pure bcc-In2O3 and a bcc-rh-In2O3 mixture towards the UVA degradation of methylene blue (MB) were also evaluated. The results showed that Er+3 doped In2O3 exhibited the highest photocatalytic activity with a photonic efficiency three times higher than the pure oxide. The improved performance was attributed to the higher surface area, the greater concentration of electron traps due the presence of the dopant and the possible formation of heterojunctions between the cubic and rhombohedral phases.Coordenacao de Aperfeicoamento de Pessoal de Nivel Superior (Capes)Conselho Nacional de Desenvolvimento Cientifico e Tecnologico (CNPq)Fundacao de Amparo a Pesquisa do Estado de Minas Gerais (FAPEMIG)FAPEMIGUniv Fed Uberlandia, Inst Quim, BR-38400902 Uberlandia, MG, BrazilUniv Fed Sao Paulo, UNIFESP, BR-09972270 Diadema, SP, BrazilUniv Estadual Paulista, Inst Quim, LIEC, BR-14800900 Araraquara, SP, BrazilUniv Fed Sao Carlos, INCTMN UFSCar, BR-13565905 Sao Carlos, SP, BrazilUniv Fed Sao Paulo, UNIFESP, BR-09972270 Diadema, SP, BrazilFAPEMIG: APQ-00988-13FAPEMIG: APQ-00330-14FAPEMIG: CEX - RED-00010-14Web of Scienc

Novel doped calcium phosphate-PMMA bone cement composites as levofloxacin delivery systems

Antibiotic-loaded acrylic bone cements (ALABCs) are well-established and cost-effective materials to control the occurrence of bone and joint infections. However, the inexistence of alternative antibiotics other than those already commercially available and the poor ability to bind to bone tissue hampering its biological function are still major drawbacks of ALABCs clinical application. The concept of this research work is to develop a novel bone cement (BC) drug delivery system composed by Mg- and Sr-doped calcium phosphate (CaP) particles as drug carriers loaded into a lactose-modified acrylic BC, which, to the best of our knowledge, has never been reported. CaP particles are known to promote bone ingrowth and current research is focused on using these carriers as antibiotic delivery systems for the treatment of bone infections, like osteomyelitis. Levofloxacin is a fluoroquinolone with anti-staphylococcal activity and adequate penetration into osteoarticular tissues and increasingly being recommended to manage bone-related infections. Also, the lactose-modified BC matrix, with a more porous structure, has already proved to enhance antibiotic release from the BC inner matrix. This novel BC composite biomaterial has shown improved mechanical integrity, biocompatibility maintenance, and sustained release of levofloxacin, with concentrations over the minimum inhibitory concentration values after a 48 h while maintaining antibacterial activity over an 8-week period against Staphyloccocus aureus and Staphyloccocus epidermidis, common pathogens associated with bone infections. (C) 2015 Elsevier B.V. All rights reserved

Geoeconomic variations in epidemiology, ventilation management, and outcomes in invasively ventilated intensive care unit patients without acute respiratory distress syndrome: a pooled analysis of four observational studies

Background: Geoeconomic variations in epidemiology, the practice of ventilation, and outcome in invasively ventilated intensive care unit (ICU) patients without acute respiratory distress syndrome (ARDS) remain unexplored. In this analysis we aim to address these gaps using individual patient data of four large observational studies. Methods: In this pooled analysis we harmonised individual patient data from the ERICC, LUNG SAFE, PRoVENT, and PRoVENT-iMiC prospective observational studies, which were conducted from June, 2011, to December, 2018, in 534 ICUs in 54 countries. We used the 2016 World Bank classification to define two geoeconomic regions: middle-income countries (MICs) and high-income countries (HICs). ARDS was defined according to the Berlin criteria. Descriptive statistics were used to compare patients in MICs versus HICs. The primary outcome was the use of low tidal volume ventilation (LTVV) for the first 3 days of mechanical ventilation. Secondary outcomes were key ventilation parameters (tidal volume size, positive end-expiratory pressure, fraction of inspired oxygen, peak pressure, plateau pressure, driving pressure, and respiratory rate), patient characteristics, the risk for and actual development of acute respiratory distress syndrome after the first day of ventilation, duration of ventilation, ICU length of stay, and ICU mortality. Findings: Of the 7608 patients included in the original studies, this analysis included 3852 patients without ARDS, of whom 2345 were from MICs and 1507 were from HICs. Patients in MICs were younger, shorter and with a slightly lower body-mass index, more often had diabetes and active cancer, but less often chronic obstructive pulmonary disease and heart failure than patients from HICs. Sequential organ failure assessment scores were similar in MICs and HICs. Use of LTVV in MICs and HICs was comparable (42·4% vs 44·2%; absolute difference -1·69 [-9·58 to 6·11] p=0·67; data available in 3174 [82%] of 3852 patients). The median applied positive end expiratory pressure was lower in MICs than in HICs (5 [IQR 5-8] vs 6 [5-8] cm H2O; p=0·0011). ICU mortality was higher in MICs than in HICs (30·5% vs 19·9%; p=0·0004; adjusted effect 16·41% [95% CI 9·52-23·52]; p<0·0001) and was inversely associated with gross domestic product (adjusted odds ratio for a US$10 000 increase per capita 0·80 [95% CI 0·75-0·86]; p<0·0001). Interpretation: Despite similar disease severity and ventilation management, ICU mortality in patients without ARDS is higher in MICs than in HICs, with a strong association with country-level economic status