Desenvolvimento de um programa computacional para classificação do uso da terra em imagens CBERS 2

Pós-graduação em Agronomia (Energia na Agricultura) - FCA

Identificação de parâmetros modais utilizando apenas as respostas da estrutura: identificação estocástica de subespaço e decomposição no domínio da frequência

Pós-graduação em Engenharia Mecânica - FEIS

Análise modal baseada apenas na resposta: decomposição no domínio da frequência

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

Análise eletromiográfica da postura do profissional de saúde no inícioe fim doexpediente de trabalho

Pós-graduação em Engenharia Mecânica - FEG

Quantitative EEG evaluation in patients with acute encephalopathy

Objetivos Investigar o uso do EEG quantitativo (qEEG) em pacientes com encefalopatias agudas (EAs ) e anormalidades da atividade de base no EEG. Método s pacientes foram divididos em prognóstico favorável (grupo A, 43 pacientes) e desfavorável (grupo B, 5 pacientes). O programa EEGLAB foi utilizado para a análise do qEEG. Um gráfico da potência espectral de todos os canais foi gerado para cada participante. Os dois grupos foram comparados estatisticamente. Resultados No grupo A, a análise espectral revelou picos (frequências teta e alfa) em 84% (38/45) dos pacientes. No grupo B, um pico espectral na frequência delta foi detectado em um paciente. Os pacientes remanescentes dos dois grupos não apresentaram picos espectrais. A análise estatística mostrou menores frequências registradas nos eletrodos posteriores dos pacientes do grupo B. Conclusão O qEEG pode ser útil na avaliação de pacientes com EAs auxiliando na determinação do prognóstico.

Singular Value Decomposition and Ligand Binding Analysis

Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES)

Effect of Pursed-Lip Breathing in Patients With COPD: Linear and Nonlinear Analysis of Cardiac Autonomic Modulation

Objective: The aim of the present study was to evaluate the effect of pursed-lip breathing (PLB) on cardiac autonomic modulation in individuals with chronic obstructive pulmonary disease (COPD) while at rest. Methods: Thirty-two individuals were allocated to one of two groups: COPD (n = 17; 67.29 +/- 6.87 years of age) and control (n = 15; 63.2 +/- 7.96 years of age). The groups were submitted to a two-stage experimental protocol. The first stage consisted of the characterization of the sample and spirometry. The second stage comprised the analysis of cardiac autonomic modulation through the recording of R-R intervals. This analysis was performed using both nonlinear and linear heart rate variability (HRV). In the statistical analysis, the level of significance was set to 5% (p = 0.05). Results: PLB promoted significant increases in the SD1, SD2, RMSSD and LF (ms(2)) indices as well as an increase in alpha(1) and a reduction in alpha(2) in the COPD group. A greater dispersion of points on the Poincare plots was also observed. The magnitude of the changes produced by PLB differed between groups. Conclusion: PLB led to a loss of fractal correlation properties of heart rate in the direction of linearity in patients with COPD as well as an increase in vagal activity and impact on the spectral analysis. The difference in the magnitude of the changes produced by PLB between groups may be related to the presence of the disease and alterations in the respiration rate.

Caracterização magnetométrica de Sill de diabásio na região de Limeira - SP

Pós-graduação em Geologia Regional - IGCE

Analysis Methodology for Vortex-Induced Motion (VIM) of a Monocolumn Platform Applying the Hilbert-Huang Transform Method

Vortex-induced motion (VIM) is a highly nonlinear dynamic phenomenon. Usual spectral analysis methods, using the Fourier transform, rely on the hypotheses of linear and stationary dynamics. A method to treat nonstationary signals that emerge from nonlinear systems is denoted Hilbert-Huang transform (HHT) method. The development of an analysis methodology to study the VIM of a monocolumn production, storage, and offloading system using HHT is presented. The purposes of the present methodology are to improve the statistics analysis of VIM. The results showed to be comparable to results obtained from a traditional analysis (mean of the 10% highest peaks) particularly for the motions in the transverse direction, although the difference between the results from the traditional analysis for the motions in the in-line direction showed a difference of around 25%. The results from the HHT analysis are more reliable than the traditional ones, owing to the larger number of points to calculate the statistics characteristics. These results may be used to design risers and mooring lines, as well as to obtain VIM parameters to calibrate numerical predictions. [DOI: 10.1115/1.4003493]

Experimental gestational hypothyroidism evokes hypertension in adult offspring rats

Gestational hypothyroidism is a prevalent disorder in pregnant women. We aimed to investigate the impact of experimental gestational hypothyroidism (EGH) on cardiovascular and autonomic nervous systems (ANS) in the offspring of rats. EGH was induced with methimazole (MMI) 0.02% in drinking water from day 9 of gestation until birth. Sixty day old offspring from MMI-treated dams (OMTD, n = 13) or water-treated dams (OWTD, n = 13) had femoral arteries surgically assessed for the measurements of heart rate (HR), mean (MAP), systolic (SAP) and diastolic arterial pressure (DAP), and spontaneous baroreflex sensitivity (BRS). To investigate the balance of ANS, we established the high (HF) and low frequency (LF) bands of pulse interval (PI) and LF band of SAP spectrum. OMTD had increased MAP (130.2 +/- 2.0 vs 108.8 +/- 3.0 mm Hg, p<0.001), SAP (157.3 +/- 2.9 vs 135.7 +/- 4.5 mm Hg, p<0.001) and DAP (109.7 +/- 1.9 vs 88.4 +/- 2.6 mm Hg, p<0.001) when compared to OWED, and had lower HR (355.1 +/- 8.9 vs 386.8 +/- 9.2 bpm, p<0.05). After spectral analysis of PI and SAP, only LF band of SAP spectrum was higher (7.2 +/- 0.8 vs 4.0 +/- 0.6 mm Hg-2, p<0.01) in OMTD under spontaneous condition. Despite bradycardia, EGH promotes spontaneous hypertension in 60 day old offspring, probably due to increased sympathetic modulation of vessels, which is suggested by the higher LF of SAP. These findings suggest a critical role of maternal THs in the development of fetal cardiovascular and autonomic nervous systems. Crown Copyright (C) 2012 Published by Elsevier B.V. All rights reserved.

Low-dose Enalapril Reduces Angiotensin II and Attenuates Diabetic-induced Cardiac and Autonomic Dysfunctions

Activation of renin-angiotensin system has been linked to cardiovascular and autonomic dysfunctions in diabetes. Experiments were performed to investigate the effects of angiotensin-converting enzyme inhibitor (ACEI), enalapril, on cardiac and autonomic functions in diabetic rats. Diabetes was induced by streptozotocin (50 mg/kg), and rats were treated with enalapril (1 mg.kg(-1).d(-1)). After 30 days, evaluations were performed in control, diabetic, and enalapril-treated groups. Cardiac function was evaluated by echocardiography and through cannulation of the left ventricle (at baseline and in response to volume overload). Heart rate and systolic blood pressure variabilities were evaluated in the time and frequency domains. Streptozotocin rats had left ventricular systolic and diastolic dysfunctions, expressed by reduced ejection fraction and increased isovolumic relaxation time. The ACEI prevented these changes, improved diastolic cardiac responses to volume overload and total power of heart rate variability, reduced the ACE1 activity and protein expression and cardiac angiotensin (Ang) II levels, and increased angiotensin-converting enzyme 2 activity, despite unchanged blood pressure. Correlations were obtained between Ang II content with systolic and diastolic functions and heart rate variability. These findings provide evidence that the low-dose ACEI prevents autonomic and cardiac dysfunctions induced by diabetes without changing blood pressure and associated with reduced cardiac Ang II and increased angiotensin-converting enzyme 2 activity.

Indagine delle proprietà statistiche di serie temporali di posizione applicata al caso della stazione permanente GPS della base Mario Zucchelli in Terra Vittoria (Antartide)

Da ormai sette anni la stazione permanente GPS di Baia Terranova acquisisce dati giornalieri che opportunamente elaborati consentono di contribuire alla comprensione della dinamica antartica e a verificare se modelli globali di natura geofisica siano aderenti all’area di interesse della stazione GPS permanente. Da ricerche bibliografiche condotte si è dedotto che una serie GPS presenta molteplici possibili perturbazioni principalmente dovute a errori nella modellizzazione di alcuni dati ancillari necessari al processamento. Non solo, da alcune analisi svolte, è emerso come tali serie temporali ricavate da rilievi geodetici, siano afflitte da differenti tipologie di rumore che possono alterare, se non opportunamente considerate, i parametri di interesse per le interpretazioni geofisiche del dato. Il lavoro di tesi consiste nel comprendere in che misura tali errori, possano incidere sui parametri dinamici che caratterizzano il moto della stazione permanente, facendo particolare riferimento alla velocità del punto sul quale la stazione è installata e sugli eventuali segnali periodici che possono essere individuati.

Strukturbildung in dünnen Filmen aus Mischungen statistischer Copolymere

Dünne Polymerfilme besitzen einen weiten Anwendungsbereich in vielen High-Tech Applikationen. All diese Anwendungen erfordern ein bestimmtes Anwendungsprofil des dünnen Films. Diese Anforderungen umschließen sowohl die physikalischen Eigenschaften des Films als auch seine Struktur. Um sie zu realisieren, werden oftmals Mischungsfilme aus verschiedenen Polymeren verwendet. Diese neigen jedoch in vielen Fällen zur bereits während der Präparation zu Phasenseparation.Vor diesem Hintergrund wurde untersucht welchen Einfluss die Verträglichkeit der gemischten Polymere auf die Strukturbildung des dünnen Films ausüben. Als Modellsystem hierfür dienten Mischungen statistischer Poly-styrol-stat-para brom-styrol Copolymere.Die Oberflächenstrukturen, die sich währen der Präparation der Mischungsfilme einstellten, wurden mit Rasterkraftmikroskopie untersucht. wobei die Topologie einer statistischen Analyse unterzogen wurde. Zum einen wurde hierzu die spektrale Leistungsdichte der Oberflächenkontour zum anderen die zugehörigen Minkowski-Funktionale berechnet.Neben Oberflächenstrukturen bilden sich während der Präparation auch Entmischungsstrukturen im inneren des Filmes. Zur Charakterisierung dieser Strukturen wurden die Filme durch Streuung unter streifendem Einfall untersucht. Durch eine modellfreie Interpretation der Streuexperimente gelang der Nachweis der inneren StrukturenFür nur schwach unverträglich Filme konnte auf Basis der Streuexperimente eine Replikation der Oberflächenstruktur des Substrates auf die Filmoberflächen nachgewiesen werden. Diese Replikation wurde für verschieden raue Substrate und bezueglich der Kinetik ihrer Abnahme beim Quellen der Filme untersucht.

Caratterizzazione e generazione di segnali PWM per amplificatori in classe D ad alta efficienza

The convergence of information technology and consumer electronics towards battery powered portable devices has increased the interest in high efficiency, low dissipation amplifiers. Class D amplifiers are the state of the art in low power consumption and high performance amplification. In this thesis we explore the possibility of exploiting nonlinearities introduced by the PWM modulation, by designing an optimized modulation law which scales its carrier frequency adaptively with the input signal's average power while preserving the SNR, thus reducing power consumption. This is achieved by means of a novel analytical model of the PWM output spectrum, which shows how interfering harmonics and their bandwidth affect the spectrum. This allows for frequency scaling with negligible aliasing between the baseband spectrum and its harmonics. We performed low noise power spectrum measurements on PWM modulations generated by comparing variable bandwidth, random test signals with a variable frequency triangular wave carrier. The experimental results show that power-optimized frequency scaling is both feasible and effective. The new analytical model also suggests a new PWM architecture that can be applied to digitally encoded input signals which are predistorted and compared with a cosine carrier, which is accurately synthesized by a digital oscillator. This approach has been simulated in a realistic noisy model and tested in our measurement setup. A zero crossing search on the obtained PWM modulation law proves that this approach yields an equivalent signal quality with respect to traditional PWM schemes, while entailing the use of signals whose bandwidth is remarkably smaller due to the use of a cosine instead of a triangular carrier.

The effect of arts speech therapy on cerebral oxygenation and low frequency hemodynamic oscillations measured using functional near-infrared spectroscopy

Introduction: As a previous study revealed, arts speech therapy (AST) affects cardiorespiratory interaction [1]. The aim of the present study was to investigate whether AST also has effects on brain oxygenation and hemodynamics measured non-invasively using near-infrared spectroscopy (NIRS). Material and methods: NIRS measurements were performed on 17 subjects (8 men and 9 women, mean age: 35.6 ± 12.7 y) during AST. Each measurement lasted 35 min, comprising 8 min pre-baseline, 10 min recitation and 20 min post-baseline. For each subject, measurements were performed for three different AST recitation tasks (recitation of alliterative, hexameter and prose verse). Relative concentration changes of oxyhemoglobin (Δ[O2Hb]) and deoxyhemoglobin (Δ[HHb]) as well as the tissue oxygenation index (TOI) were measured using a Hamamatsu NIRO300 NIRS device and a sensor placed on the subjects forehead. Movement artifacts were removed using a novel method [2]. Statistical analysis (Wilcoxon test) was applied to the data to investigate (i) if the recitation causes changes in the median values and/or in the Mayer wave power spectral density (MW-PSD, range: 0.07–0.13 Hz) of Δ[O2Hb], Δ[HHb] or TOI, and (ii) if these changes vary between the 3 recitation forms. Results: For all three recitation styles a significant (p < 0.05) decrease in Δ[O2Hb] and TOI was found, indicating a decrease in blood flow. These decreases did not vary significantly between the three styles. MW-PSD increased significantly for Δ[O2Hb] when reciting the hexameter and prose verse, and for Δ[HHb] and TOI when reciting alliterations and hexameter, representing an increase in Mayer waves. The MW-PSD increase for Δ[O2Hb] was significantly larger for the hexameter verse compared to alliterative and prose verse Conclusion: The study showed that AST affects brain hemodynamics (oxygenation, blood flow and Mayer waves). Recitation caused a significant decrease in cerebral blood flow for all recitation styles as well as an increase in Mayer waves, particularly for the hexameter, which may indicate a sympathetic activation. References 1. D. Cysarz, D. von Bonin, H. Lackner, P. Heusser, M. Moser, H. Bettermann. Am J Physiol Heart Circ Physiol, 287 (2) (2004), pp. H579–H587 2. F. Scholkmann, S. Spichtig, T. Muehlemann, M. Wolf. Physiol Meas, 31 (5) (2010), pp. 649–662