Campus Universitario

Viçosa, Brazil

Campus Universitario

Viçosa, Brazil
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Fernandez S.,Complutense University of Madrid | Naranjo F.B.,Campus Universitario
Solar Energy Materials and Solar Cells | Year: 2010

Aluminum-doped zinc oxide films were deposited at 100 °C on polyethylene terephthalate by radio-frequency magnetron sputtering. The sputtering parameters such as RF power and Argon working pressure were varied from 25 to 125 W and from 1.1 to 0.2 Pa, respectively. The structural properties of as-deposited films were analysed by X-ray diffraction, showing that all the deposited films were polycrystalline, with hexagonal structure and a strong preferred c-axis orientation (0 0 2). Full width at half maximum and grain sizes were around 0.27° and ranged from 24 to 32 nm, respectively. The strain state of the samples was also estimated from X-ray diffraction measurements, obtaining compressive stresses from 0.29 to 0.05 GPa. Resistivity as low as 1.1×10-3 Ω cm was achieved for the film deposited at 75 W and 0.2 Pa, sample that showed a low strain state of -0.06 GPa. High optical transmittance (∼80%) was exhibited when films were deposited at RF powers below 100 W. Band gap energies ranged from 3.36 to 3.39 eV and a refractive index of 1.80±0.05, constant in the visible region, was also obtained. © 2009 Elsevier B.V. All rights reserved.

Partidario M.R.,University of Lisbon | Coutinho M.,Campus Universitario
Environmental Impact Assessment Review | Year: 2011

This is the brief story of a decision process and the role of Strategic Environmental Assessment in government political decision-making. Following a prolonged, and agitated, decision process, initiated in the 1960s, the Government of Portugal in 2005 took the final decision to build the new international airport of Lisbon at the controversial location of Ota, 40. km north of Lisbon. The detailed project design and EIA were started. However this decision would change in 2007 due to the challenge raised by a private sponsored study that identified an alternative location for the airport at Campo de Tiro de Alcochete (CTA). This new site, which had never been considered as an option before, appeared to avoid many of the problems that caused public controversy at the Ota site. The Government, pressured by this challenge, promoted a strategic comparative assessment between the two sites. The result of this study was the choice of CTA as the preferred location. This paper discusses this radical change in the decision from a socio-political perspective. It will highlight the relevance of Strategic Environmental Assessment (SEA), and the strategic and constructive approach it enables in mega-project decision-making. © 2010 Elsevier Inc.

Panek L.,Campus Universitario | Firer M.,University of Campinas | Alves M.M.S.,Federal University of Paraná
IEEE Transactions on Information Theory | Year: 2010

Poset and block metrics were introduced in recent years as alternative metrics to study error correcting codes. Poset-block codes were introduced in 2008, encompassing both poset and block metrics. In this paper, we study a family of such metrics, the Niederreiter-Rosenbloom-Tsfasman block metrics. In this context, we classify the classes of equivalent codes, describe canonical representatives of each class and develop much of the classical theory of error correcting codes for Niederreiter-Rosenbloom-Tsfasman block codes, including determination of packing radius and classification of MDS and perfect codes, determination of covering radius and characterization of quasi-perfect codes, and the description of an algorithm for syndrome decoding. © 2010 IEEE.

Dunlop J.A.,Leibniz Institute for Evolution and Biodiversity Science | De Oliveira Bernardi L.F.,Campus Universitario
Naturwissenschaften | Year: 2014

A fossil opilioacarid mite (Parasitiformes: Opilioacarida) in Burmese amber is described as ?Opilioacarus groehni sp. nov. This ca. 99 Ma record (Upper Cretaceous: Cenomanian) represents only the third fossil example of this putatively basal mite lineage, the others originating from Eocene Baltic amber (ca. 44-49 Ma). Our new record is not only the oldest record of Opilioacarida, but it is also one of the oldest examples of the entire Parasitiformes clade. The presence of Opilioacarida - potentially Opiloacarus - in the Cretaceous of SE Asia suggests that some modern genus groups were formerly more widely distributed across the northern hemisphere, raising questions about previously suggested Gondwanan origins for these mites. © 2014 Springer-Verlag Berlin Heidelberg.

The terminology used in the paleoanatomical study of gymnospermous woods, proceeding from Carboniferous and Permian of Gondwana, is characterized by vagueness of criteria regarding the selection of the characteristics of taxonomic value. In this regard, a greater negligence is comparatively emphasized in relation to the pith than the other units that composed the stem and the lack of uniformity in the nomenclature used in primary and secondary xylem paleoanatomy. Such procedures have led to elaboration of incomplete generic and specific descriptions, to the difficulty of comparison between the specimens and, often, to the inadequate taxonomic. Thus, aiming at the definition of the features of taxonomic value and the standardization of terminology, a methodology based on proposition and discussion of the anatomical characteristics of the pith and primary and secondary xylem used to inter-taxa differentiation of the Gondwana gymnospermous woods is presented. Notes about the anatomy of the other units of stem, neighboring the secondary xylem, and illustrations of taxa that exhibit the characters considered are also presented.

Hermida R.C.,Campus Universitario | Ayala D.E.,Campus Universitario | Mojon A.,Campus Universitario | Fernandez J.R.,Campus Universitario
Journal of the American College of Cardiology | Year: 2011

Objectives: We investigated whether reduced cardiovascular risk is more related to the progressive decrease of asleep or awake blood pressure. Background: Independent studies have concluded that elevated sleep-time blood pressure is a better predictor of cardiovascular risk than awake or 24-h blood pressure means. However, the impact on cardiovascular risk of changes in these ambulatory blood pressure characteristics has not been properly investigated. Methods: We prospectively studied 3,344 subjects (1,718 men and 1,626 women), 52.6 ± 14.5 years of age, during a median follow-up of 5.6 years. Those with hypertension at baseline were randomized to ingest all their prescribed hypertension medications upon awakening or <1 of them at bedtime. Blood pressure was measured for 48 h at baseline and again annually or more frequently (quarterly) if treatment adjustment was required. Results: With data collected at baseline, when asleep blood pressure was adjusted by awake mean, only the former was a significant predictor of outcome in a Cox proportional hazards model also adjusted for sex, age, and diabetes. Analyses of changes in ambulatory blood pressure during follow-up revealed a 17% reduction in cardiovascular risk for each 5-mm Hg decrease in asleep systolic blood pressure mean (p < 0.001), independently of changes in any other ambulatory blood pressure parameter. Conclusions: The sleep-time blood pressure mean is the most significant prognostic marker of cardiovascular morbidity and mortality. Most importantly, the progressive decrease in asleep blood pressure, a novel therapeutic target that requires proper patient evaluation by ambulatory monitoring, was the most significant predictor of event-free survival. (Prognostic Value of Ambulatory Blood Pressure Monitoring in the Prediction of Cardiovascular Events and Effects of Chronotherapy in Relation to Risk [the MAPEC Study]; NCT00295542) © 2011 American College of Cardiology Foundation.

Diaz Pace D.M.,Campus Universitario
Journal of Quantitative Spectroscopy and Radiative Transfer | Year: 2013

In this paper, line profile analysis of several Cr transitions was carried out for characterization of a laser-induced plasma. The plasma was generated on a metallic alloy (nominal Cr concentration 29.7%) in air at atmospheric pressure by using an infrared Nd:YAG laser. The emission intensities of 24 Cr I lines and 25 Cr II lines were measured spatially integrated along the line-of-sight with good resolution. Their line profiles were analyzed applying a computational fitting algorithm under a framework of a homogeneous plasma in thermodynamic equilibrium. The effects of self-absorption and spatial inhomogeneity were taken into account. The plasma temperature and the parameters Nl (the atom/ion concentration times the length of the plasma along the line-of-sight) were accurately determined, and the electron density was estimated. The results were properly interpreted under the employed approach, demonstrating the important influence of the issues investigated on characterizing the physical state of laser-induced plasmas. © 2013 Elsevier Ltd.

Hermida R.C.,Campus Universitario | Ayala D.E.,Campus Universitario | Mojon A.,Campus Universitario | Fernandez J.R.,Campus Universitario
Chronobiology International | Year: 2013

Numerous studies have consistently shown an association between blunted sleep-time relative blood pressure (BP) decline (non-dipping) and increased cardiovascular disease (CVD) risk in hypertension. Normotensive persons with a non-dipper BP profile also have increased target organ damage, namely, increased left ventricular mass and relative wall thickness, reduced myocardial diastolic function, increased urinary albumin excretion, increased prevalence of diabetic retinopathy, and impaired glucose tolerance. It remains a point of contention, however, whether the non-dipper BP pattern or just elevated BP, alone, is the most important predictor of advanced target organ damage and future CVD events. Accordingly, we investigated the role of dipping status and ambulatory BP level as contributing factors for CVD morbidity and mortality in the MAPEC (Monitorización Ambulatoria para Predicción de Eventos Cardiovasculares, i.e., Ambulatory Blood Pressure Monitoring for Prediction of Cardiovascular Events) study. We prospectively studied 3344 individuals (1718 men/1626 women), 52.6 ± 14.5 (mean ± SD) yrs of age, during a median follow-up of 5.6 yrs. BP was measured by ambulatory monitoring (ABPM) for 48 h at baseline, and again annually or more frequently (quarterly) if treatment adjustment was required in treated hypertensive patients. At baseline, those with ABPM-substantiated hypertension were randomized to one of two treatment-time regimen groups: (i) ingestion of all prescribed hypertension medications upon awakening or (ii) ingestion of the entire dose of ≥1 of them at bedtime. Those found to be normotensive at baseline were untreated but followed and evaluated by repeated ABPM like the hypertensive patients. Participants were divided into four investigated categories on the basis of dipping status and ambulatory BP: (i) dipper vs. non-dipper, and (ii) normal ambulatory BP if the awake systolic (SBP)/diastolic (DBP) BP means were <135/85 mm Hg and the asleep SBP/DBP means were <120/70 mm Hg, and elevated ambulatory BP otherwise. Cox survival analyses, adjusted for significant confounding variables, documented that non-dippers had significantly higher CVD risk than dippers, whether they had normal (p = .017) or elevated ambulatory BP (p < .001). Non-dippers with normal awake and asleep SBP and DBP means, who accounted for 21% of the studied population, had similar hazard ratio (HR) of CVD events (1.61 [95% confidence interval, CI: 1.09-2.37]) as dippers with elevated ambulatory BP (HR: 1.54 [95% CI: 1.01-2.36]; p = .912 between groups). These results remained mainly unchanged for treated and untreated patients analyzed separately. Our findings document that the risk of CVD events is influenced not only by ambulatory BP elevation, but also by blunted nighttime BP decline, even within the normotensive range, thus supporting ABPM as a requirement for proper CVD risk assessment in the general population. The elevated CVD risk in "normotensive" individuals with a non-dipper BP profile represents a clear paradox, as those persons do not have "normal BP" or low CVD risk. Our findings also indicate the need to redefine the concepts of normotension/hypertension, so far established on the unique basis of BP level, mainly if not exclusively measured at the clinic, independently of circadian BP pattern. Copyright © Informa Healthcare USA, Inc.

Barbosa M.N.,Campus Universitario | Da Silva Mota M.T.,Campus Universitario
American Journal of Primatology | Year: 2013

Parental care in mammals is influenced by sensory stimuli from infants, and by changes in the hormone levels of caretakers. To determine the responsiveness to infant cues in nonreproductive adult male common marmosets (Callithrix jacchus) with and without previous experience in caretaking, we exposed 12 males to newborn marmosets and assessed their cortisol plasma levels and behavioral response. Newborn marmosets housed in transparent enclosures were placed inside the cages of the adult male subjects. Males were exposed four times to two different experimental conditions: (a) newborn enclosures remained closed during the observation period and (b) newborn enclosures were opened during the observation period to allow direct social interaction by the adult males. Blood samples from adult males were collected after each behavioral observation trial to measure the levels of cortisol. The behavioral responses of adult males exposed to the closed and open newborn enclosures showed a significant difference only with respect to the frequency of displacements, where males moved among the quadrants of their own cages with greater frequency when the newborn enclosure was sealed. Experienced males approached newborn enclosures more frequently, spent more time in close proximity, and carried and recovered newborns more quickly than inexperienced males. The successive exposure to newborns increased the responsiveness in inexperienced males. The highest levels of plasma cortisol in adult males were recorded following periods of exposure to the sealed newborn enclosures. This suggests that successive exposure to newborns and previous alloparental caregiving experience while living in family groups influences the responsiveness of male marmosets to the sensory cues of newborns. © 2012 Wiley Periodicals, Inc.

Matos V.L.D.,Campus Universitario | Finardi E.C.,Campus Universitario
International Journal of Electrical Power and Energy Systems | Year: 2012

The long-term hydrothermal scheduling is one of the most important problems that must be solved in power systems area. This problem aims to obtain an optimal policy, under water resources uncertainty, for the hydro and thermal plants over a multi-annual planning horizon. The purpose of this paper is twofold. Firstly, we present a computational model which is in development for solving the long-term hydrothermal scheduling of the Brazilian hydrothermal power system. Secondly, it is described some modeling issues which may cause problems to achieve an optimal policy and are currently included in the official long-term optimization model of the Brazilian regulatory framework. This paper presents some solutions, for those problems, that were implemented on our model. We evaluate the solutions related to the original modeling and the modified one, in order to show evidences of the problems and that the solutions proposed are a good start point. To accomplish this evaluation, we consider in the model the whole Brazilian power system, with a reduced planning horizon. © 2012 Elsevier Ltd. All rights reserved.

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