Very Intense Distinct Blue and Red Photoluminescence Emission in MgTiO 3 Thin Films Prepared by the Polymeric Precursor Method: An Experimental and Theoretical Approach

MgTiO3 (MTO) thin films were prepared by the polymeric precursor method with posterior spin-coating deposition. The films were deposited on Pt(111)/Ti/SiO2/Si(100) substrates and heat treated at 350 °C for 2 h and then heat treated at 400, 450, 500, 550, 600, 650 and 700 °C for 2 h. The degree of structural order−disorder, optical properties, and morphology of the MTO thin films were investigated by X-ray diffraction (XRD), micro-Raman spectroscopy (MR), ultraviolet− visible (UV−vis) absorption spectroscopy, photoluminescence (PL) measurements, and field-emission gun scanning electron microscopy (FEG-SEM) to investigate the morphology. XRD revealed that an increase in the annealing temperature resulted in a structural organization of MTO thin films. First-principles quantum mechanical calculations based on density functional theory (B3LYP level) were employed to study the electronic structure of ordered and disordered asymmetric models. The electronic properties were analyzed, and the relevance of the present theoretical and experimental results was discussed in the light of PL behavior. The presence of localized electronic levels and a charge gradient in the band gap due to a break in the symmetry are responsible for the PL in disordered MTO lattice.

Parameters optimization of heat treatment for obtaining luminescent PZT powders

Low crystalline PZT powder samples were successfully synthesized using polymeric precursor method and slow decomposition steps. The polymeric resin precursor was thermal treated in a muffle type oven varying the temperature from 250 °C to 700 °C and the time from 3 to 24 hours in order to investigate the order/disorder mechanism toward the amorphous powders. Powder samples with low crystalline phases were obtained at lower temperatures and long time of thermal treatment, demonstrating a kinetic dependence for organic removal and a thermodynamic barrier for crystallization processes. Through XRD and FTIR spectroscopy characterizations the long time thermal treated samples showed to be composed of the solid solution of metal oxides in absent of organic matter, originating broad XRD peaks profiles and no carbonaceous bands in FTIR spectra. A Photoluminescence characterization showed that the peak emission is higher for disordered and homogeneous phases, which only can be reached through the long time of thermal treatment.

Função pulmonar em indivíduos com SAOS antes e após o uso do CPAP: estudo randomizado duplo cego

Pós-graduação em Bases Gerais da Cirurgia - FMB

Convivendo com o lixo: a vulnerabilidade socioambiental no bairro Jardim Graminha, Leme, Sao Paulo

Urban space occupation occurs in an extremely disordered way. Political, economical and social aspects converge to create a problem that affects mostly poor people who are impelled to occupy areas where social and environmental problems are likely to emerge. Floods, landslides and different forms of pollution have more effects on the most vulnerable groups. In many cases, actions taken by the government legitimate this structure and reinforce its reproduction. This work seeks to confirm both that poor people are vulnerable to social and environmental problems resulting from inappropriate urban solid waste disposal and that the local government contributes to this situation. It is assumed that the issue is related first to the government’s disregard for poor people who live in unhealthy places and, second, to the inability of such people to demand for better living conditions. In this study, a waste disposal area within Jardim Graminha neighborhood in Leme (São Paulo) was selected to be analyzed by means of systematic observation. The study clearly shows that poor people living near that area where different types of garbage are disposed are vulnerable and the government does not control the situation. It is also pointed out that governmental intervention and the use of political and technical tools are necessary for planning and managing the area to mitigate these problems and to decrease poor people’s social and environmental vulnerability.

Síntese, estrutura e atividade de peptídeos derivados de ParD, o antídoto do módulo toxina-antitoxina ParDE

Pós-graduação em Biotecnologia - IQ

De Flaubert para Maupassant

This article aims to present some reflections about a selection of letters that Gustave Flaubert (1821-1880) wrote to Guy de Maupassant (1850-1893), between September 23, 1872 and May 3, 1880. For eight years, Flaubert was Maupassant’s friend and a literary master and his letters, marked by a multiple and disordered discourse, reveal a path to friendship and the passionate dedication of the master regarding the intellectual and artistic development of the young writer. It is intended here, to draw some considerations to the moments when Flaubert’s speech assumes, directly or indirectly, a pedagogical role and the letter becomes a way to literary teaching.

Photoluminescence of BaZrO3 explained by a order/disorded transformation

Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq)

Two-dimensional nonlinear map characterized by tunable Levy flights

Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)

Descrição e análise de contingências presentes em legislações referentes à mobilidade urbana

Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)

Repercussões cardiovasculares em crianças com distúrbios respiratórios obstrutivos do sono: revisão de literatura

Objective: To review the cardiovascular consequences of obstructive sleep-disordered breathing in children Data source: Medline and Ovid data base. Study selection: pediatric articles (original articles and case report) that investigated the obstructive sleep-disordered breathing in children Data synthesis: The obstructive sleep-disordered breathing can lead to serious cardiovascular consequences such as pulmonary hypertension, pulmonary edema and anatomic and functional abnormalities Conclusions: The knowledge of cardiovascular repercussions allows in better management of pediatric patients and may result in positive consequences for treatment and follow up of these patients.

O espaço-tempo não comutativo em Teoria Quântica de Campos, Matéria Condensada Mole e Física Biológica

Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES)

Polysomnografic findings of obstrutive sleep apnea in children with adenotonsillar hypertrophy

Serous Background: There are few studies assessing the clinical manifestations of sleep breathing disorders and polysomnograms in several pediatric age ranges. This studied aimed to assess polysomnography results such as apnea-hypopnea index, mean oxygen saturation and sleep efficiency in children presenting with airway obstruction and adenotonsillar hypertrophy complaints, and to establish whether they are correlated to age and sex. Methods: A retrospective study with children of both sexes, aged between 2 and 12 years, with clinically suspected obstructive sleep apnea syndrome and adenotonsillar hypertrophy, who underwent polysomnography before surgery. The children were allocated to groups according to their age range (Group I: 2 to 4 years old; Group II: 5 to 8 years old; Group III: 9 to 12 years old). Apnea-hypopnea index, mean oxygen saturation and sleep efficiency data were compared between sexes and among the three groups (Student’s t test, p < 0.05). Results: Of 167 children studied by polysomnography, 76.6% were of school age and 67% were male. For all studied age ranges, there was no difference between sexes for the investigated parameters (body mass index, apnea-hypopnea index, mean oxygen saturation and sleep efficiency). As regards mean oxygen saturation, Group I showed the lowest value (89.9 ± 6.2). Apnea-hypopnea indexes were higher in male children aged between 2 and 4 years (9.9 ± 5.2). Group III had the lowest sleep efficiency (84.1 ± 9.2). Conclusion: There was a predilection of more severe cases of obstructive sleep apnea syndrome for children younger than four years, shown by higher apnea-hypopnea index per hour and lower mean oxygen saturation in this age range.

Obtenção de nanofibras de carbono a partir do processo de eletrofiação

Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES)