Universidade Federal de Minas Gerais is a federal university located in Belo Horizonte, state of Minas Gerais, Brazil. UFMG is one of Brazil's five largest universities, being the largest federal university. It offers 75 undergraduate degrees, including a Medicine degree, Law and Economics, plus Engineering and Science and Art degrees. It offers 57 PhD programs, 66 MSc programs, 79 Post-Baccalaureate programs and 38 medical internship programs. UFMG has a population of 49,254 students.The undergratuate students are admitted through the national biannual exams called Unified Selection System . Its undergraduate courses were ranked in 1st place in the 2007 results for the National Student's Performance Exam and 4th place in the 2008 results. Its Computer Science course was considered the best in the country, as well the Social science course, from FAFICH by the latest edition of ENADE.The rector of UFMG is Clelio Campolina Diniz. Past students include former Brazilian presidents Juscelino Kubitschek and Tancredo Neves; writer, medical doctor and diplomat João Guimarães Rosa, writers Fernando Sabino, Pedro Nava and Cyro dos Anjos; plastic surgeon Ivo Pitanguy, poet Carlos Drummond de Andrade and musicians Fernando Brant, Samuel Rosa of Skank and Fernanda Takai of Pato Fu.UFMG is the tenth in the rankings of best universities in Latin America, according QS World University Rankings . As reported by the Academic Ranking of World Universities , UFMG is one of the five best universities in Brazil in 2013, and in the World Rank is in the range of 301-400 best universities. Wikipedia.
Souza F.O.,Federal University of Minas Gerais
IET Control Theory and Applications | Year: 2013
The delay-dependent stability problem for systems with time-delay varying in an interval is addressed in this study. Based on Lyapunov-Krasovskii theory the proposed methods formulated as linear matrix inequality problems are able to check the stability interval when the time-varying delay d(t) belongs to an interval [τ1, τ2]. The Lyapunov - Krasovskii functional (LKF) selected in the present paper is simpler than some ones considered in the literature. However, the criteria obtained, based on this simple LKF, outperformed the similar existing ones in all numerical tests accomplished in this paper. Notation: Through out this paper the superscript T stands for transpose. 0 refers to a null matrix with appropriate dimensions. For a real symmetric matrix M, the notation M> 0 (< 0) means that M is the positive (negative) definite. The symmetric term in a matrix is denoted by *. © The Institution of Engineering and Technology 2013.
Saldanha P.L.,Federal University of Minas Gerais
Optics Express | Year: 2010
It is proposed a natural and consistent division of the momentum of electromagnetic waves in linear, non-dispersive and non-absorptive dielectric and magnetic media into material and electromagnetic parts. The material part is calculated using directly the Lorentz force law and the electromagnetic momentum density has the form ε0E× B, without an explicit dependence on the properties of the media. The consistency of the treatment is verified through the obtention of a correct momentum balance equation in many examples and showing the compatibility of the division with the Einstein's theory of relativity by the use of a gedanken experiment. An experimental prediction for the radiation pressure on mirrors immersed in linear dielectric and magnetic media is also made. © 2010 Optical Society of America.
Saldanha P.L.,Federal University of Minas Gerais
Physical Review A - Atomic, Molecular, and Optical Physics | Year: 2014
In an recent work with the title "Asking Photons Where They Have Been," Danan et al. experimentally demonstrate an intriguing behavior of photons in an interferometer [Phys. Rev. Lett. 111, 240402 (2013)PRLTAO0031- 900710.1103/PhysRevLett.111.240402]. In their words: "The photons tell us that they have been in the parts of the interferometer through which they could not pass." They interpret the results using the two-state vector formalism of quantum theory and say that, although an explanation of the experimental results in terms of classical electromagnetic waves in the interferometer is possible (and they provide a partial description), it is not so intuitive. Here we present a more detailed classical description of their experimental results, showing that it is actually intuitive. The same description is valid for the quantum wave function of the photons propagating in the interferometer. In particular, we show that it is essential that the wave propagates through all parts of the interferometer to describe the experimental results. We hope that our work helps to give a deeper understanding of these interesting experimental results. © 2014 American Physical Society.
Ribeiro A.L.,Federal University of Minas Gerais
Journal of the American Heart Association | Year: 2014
Electrocardiography has been considered an important tool in the management of Chagas disease (ChD) patients, although its value in elderly infected patients is unknown. This study was designed to investigate the prevalence and prognostic value of electrocardiographic abnormalities in Trypanosoma cruzi infected and noninfected older adults. We studied 1462 participants in Bambuí City, Brazil, with electrocardiogram (ECG) records classified by the Minnesota Code. Follow-up time was 10 years; the endpoint was mortality. Adjustment for potential confounding variables included age, gender, conventional risk factors, and B-type natriuretic peptide (BNP). The mean age was 69 years (60.9% women). The prevalence of ChD was 38.1% (n=557). ECG abnormalities were more frequent in ChD patients (87.6% versus 77.7%, P<0.001). Right bundle branch block (RBBB) with left anterior hemiblock (LAH) was strongly related to ChD (OR: 11.99 [5.60 to 25.69]). During the mean follow-up time of 8.7 years, 556 participants died (253 with ChD), and only 89 were lost to follow-up. ECG variables of independent prognostic value for death in ChD included absence of sinus rhythm, frequent ventricular and supraventricular premature beats, atrial fibrillation, RBBB, old and possible old myocardial infarction, and left ventricular hypertrophy. The presence of any major ECG abnormalities doubled the risk of death in ChD patients (HR: 2.18 [1.35 to 3.53]), but it also increased the risk in non-ChD subjects (HR: 1.50 [1.07 to 2.10]); the risk of death increased with the number of major abnormalities in the same patient. ECG abnormalities are more common among elderly Chagas disease patients and strongly predict adverse outcomes.
Sandoval J.R.,Federal University of Minas Gerais
PloS one | Year: 2013
The Altiplano region of the South American Andes is marked by an inhospitable climate to which the autochthonous human populations adapted and then developed great ancient civilizations, such as the Tiwanaku culture and the Inca Empire. Since pre-Columbian times, different rulers established themselves around the Titicaca and Poopo Lakes. By the time of the arrival of Spaniards, Aymara and Quechua languages were predominant on the Altiplano under the rule of the Incas, although the occurrence of other spoken languages, such as Puquina and Uruquilla, suggests the existence of different ethnic groups in this region. In this study, we focused on the pre-Columbian history of the autochthonous Altiplano populations, particularly the Uros ethnic group, which claims to directly descend from the first settlers of the Andes, and some linguists suggest they might otherwise be related to Arawak speaking groups from the Amazon. Using phylogeographic, population structure and spatial genetic analyses of Y-chromosome and mtDNA data, we inferred the genetic relationships among Uros populations (Los Uros from Peru, Uru-Chipaya and Uru-Poopo from Bolivia), and compared their haplotype profiles with eight Aymara, nine Quechua and two Arawak (Machiguenga and Yanesha) speaking populations from Peru and Bolivia. Our results indicated that Uros populations stand out among the Altiplano populations, while appearing more closely related to the Aymara and Quechua from Lake Titicaca and surrounding regions than to the Amazon Arawaks. Moreover, the Uros populations from Peru and Bolivia are genetically differentiated from each other, indicating a high heterogeneity in this ethnic group. Finally, our results support the distinctive ancestry for the Uros populations of Peru and Bolivia, which are likely derived from ancient Andean lineages that were partially replaced during more recent farming expansion events and the establishment of complex civilizations in the Andes.