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Rio de Janeiro, Brazil

The Fluminense Federal University is one of the four federally funded public universities in the State of Rio de Janeiro, Brazil. The university was established by federal law on December 18, 1960. It is the union of five federal colleges and three state colleges. It has about 50,000 undergraduate students, and 12,000 graduate students . It has six campuses in the city of Niterói, on the southeast side of Guanabara Bay, and 12 satellite campuses in towns of the state. There are 68 undergraduate and 208 graduate programs available at UFF in Natural and Social science.The word fluminense in Portuguese, from Latin flumen , is the native adjective for the state of Rio de Janeiro.The Law School of Fluminense Federal University was founded in 1912. The School of Medicine of Fluminense Federal University is one of the Brazilian leading schools in scientific research and article publications.UFF holds the first undergraduate course in Film ever created in Brazil, founded by Nelson Pereira dos Santos. Wikipedia.

Reis M.S.,Federal University of Fluminense
Applied Physics Letters | Year: 2012

The magnetocaloric effect of non-relativistic diamagnetic materials presents an oscillatory character due to the crossing of the Landau levels with the Fermi energy. This effect occurs at low temperature (ca 1 K) and high magnetic field (ca 10 T). Considering the relativistic properties of graphenes, a 2D massless diamagnetic material, these oscillations could be preserved and the effect occurs in a much higher temperature (ca 100 K), due to the huge Fermi velocity (106 m/s). In addition, the magnetocaloric effect can be tuned as either inverse or normal, by changing the magnetic field change in ca 3.4 T. © 2012 American Institute of Physics. Source

Mattos L.V.,Federal University of Fluminense | Jacobs G.,University of Kentucky | Davis B.H.,University of Kentucky | Noronha F.B.,Brazilian National Institute of Technology
Chemical Reviews | Year: 2012

Significant progress has been made in gaining insight into the reaction mechanisms of ethanol reforming. To this end, infrared spectroscopy has been a powerful tool in achieving this goal. The dissociation of ethanol to ethoxy species can occur on the support, and those with sufficiently labile O adatoms or OH groups offer a means of accomplishing this step. Dehydrogenation of the ethoxy species to acetaldehyde is very likely assisted by the metal particles added to the support, as well as the presence of labile O adatoms or hydroxyl groups located on the support. A major route to catalyst deactivation is that of carbon formation. Temperature-programmed oxidation, used to characterize the nature of carbon deposits, demonstrated significant amounts of carbon deposited on the catalyst surface. The metal appears to operate across the metal-oxide junction to assist in hydrogen transfer and related reactions such as acetate demethanation. Source

Soares R.L.S.,Federal University of Fluminense
World Journal of Gastroenterology | Year: 2014

Irritable bowel syndrome (IBS) remains a clinical challenge in the 21st century. It's the most commonly diagnosed gastrointestinal condition and also the most common reason for referral to gastroenterology clinics. Its can affect up to one in five people at some point in their lives, and has a significantly impact of life quality and health care utilization. The prevalence varies according to country and criteria used to define IBS. Various mechanisms and theories have been proposed about its etiology, but the biopsychosocial model is the most currently accepted for IBS. The complex of symptoms would be the result of the interaction between psychological, behavioral, psychosocial and environmental factors. The diagnosis of IBS is not confirmed by a specific test or structural abnormality. It is made using criteria based on clinical symptoms such as Rome criteria, unless the symptoms are thought to be atypical. Today the Rome Criteria III is the current goldstandard for the diagnoses of IBS. Secure positive evidence of IBS by means of specific disease marker is currently not possible and cannot be currently recommended for routine diagnosis. There is still no clinical evidence to recommend the use of biomarkers in blood to diagnose IBS. However, a number of different changes in IBS patients were demonstrated in recent years, some of which can be used in the future as a diagnostic support. IBS has no definitive treatment but could be controlled by non-pharmacologic management eliminating of some exacerbating factors such certain drugs, stressor conditions and changes in dietary habits. The traditional pharmacologic management of IBS has been symptom based and several drugs have been used. However, the cornerstone of its therapy is a solid patient physician relationship. This review will provide a summary of pathophysiology, diagnostic criteria and current and emerging therapies for IBS. © 2014 Baishideng Publishing Group Inc. All rights reserved. Source

Reis M.S.,Federal University of Fluminense
Applied Physics Letters | Year: 2011

This Letter presents the oscillatory behavior found in the magnetic entropy change of diamagnetic materials. We show that this quantity depends on the oscillating term and, as a consequence, the magnetocaloric potential can be tuned as either inverse or normal, depending on the value of the magnetic field change. A quite small change (≈10-3 T) of the magnetic field change is able to invert the magnetic entropy change. These results open doors for applications at quite low temperatures and can be further developed to be incorporated into adiabatic demagnetization refrigerators, as well as sensible magnetic field sensors. © 2011 American Institute of Physics. Source

Rakov N.,Federal University of Vale do Sao Francisco | Maciel G.S.,Federal University of Fluminense
Optics Letters | Year: 2014

Er3+ doped powders are generally used for fluorescence-based temperature sensing application when near-infrared lasers are the excitation sources of choice. The fluorescence of Er3+ is produced by nonlinear (upconversion) processes, which generate strong internal heat. Lowering the excitation power causes drastic reduction of the fluorescence signal, and as a consequence the sensor applicability of Er3+ doped powders becomes compromised. Here we propose the use of the downconverted fluorescence of Yb3+ produced by efficient energy transfer from Nd3+ as an alternative temperature sensing system. Our results are presented for yttrium silicate powders prepared by combustion synthesis. © 2014 Optical Society of America. Source

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