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Desenvolvimento de circuitos planares sobre substratos t?xteisCavalcante, Gustavo Ara?jo 28 April 2014 (has links)
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Previous issue date: 2014-04-28 / Coordena??o de Aperfei?oamento de Pessoal de N?vel Superior / The use of flexible materials for the development of planar circuits is one of the
most desired and studied characteristics, lately, by researchers. This happens because
the flexibility of the substrate can provide previously impracticable applications, due to
the rigidity of the substrates normally used that makes it difficult to fit into the circuits
in irregular surfaces. The constant interest in recent years for more lighter devices,
increasingly more compacts, flexible and with low cost, led to a new line of research of
great interest from both academic and technological views, that is the study and
development of textile substrates that can be applied in the development of planar
circuits, for applications in the areas of security, biomedical and telecommunications.
This paper proposes the development of planar circuits, such as antennas , frequency
selective surfaces (FSS) and planar filters, using textile (cotton ticking, jeans and brim
santista) as the dielectric substrate and the Pure Copper Polyester Taffeta Fabric, a
textile of pure copper, highly conductive, lightweight and flexible, commercially sold
as a conductive material. The electrical characteristics of textiles (electric permittivity
and loss tangent) were characterized using the transmission line method (rectangular
waveguide) and compared with those found in the literature. The structures were
analyzed using commercial software Ansoft Designer and Ansoft HFSS, both from the
company Ansys and for comparison we used the Iterative Method of Waves (WCIP).
For the purpose of validation were built and measured several prototypes of antennas,
planar filters and FSS, being possible to confirm an excellent agreement between
simulated and measured results / A utiliza??o de materiais flex?veis para o desenvolvimento de circuitos planares ? uma das caracter?sticas mais desejadas e estudadas, ultimamente, pelos pesquisadores, pois essa maleabilidade do substrato proporciona aplica??es antes imposs?veis, devido ? rigidez dos substratos normalmente utilizados o que dificultava a adequa??o dos circuitos em superf?cies irregulares. O constante interesse nos ?ltimos anos por dispositivos mais leves, cada vez mais compactos, flex?veis e com custo reduzido, levou a uma nova linha de pesquisa de grande interesse tanto do ponto de vista acad?mico quanto tecnol?gico que ? o estudo e desenvolvimento de substratos t?xteis que possam ser aplicados no desenvolvimento de circuitos planares, para aplica??es nas ?reas de seguran?a, biom?dica e telecomunica??es. Este trabalho prop?e o desenvolvimento de circuitos planares, tais como antenas, superf?cies seletivas de frequ?ncia (FSS) e filtros planares, utilizando tecidos (lona, jeans e brim santista) como substrato diel?trico e o tecido Pure Copper Polyester Taffeta Fabric, um tecido de cobre puro, altamente condutivo, leve e flex?vel, comercialmente vendido como material condutivo. As caracter?sticas el?tricas dos tecidos (permissividade el?trica e tangente de perda) foram determinadas utilizando o m?todo de linha de transmiss?o e comparadas com os encontrados na literatura. As estruturas foram analisadas utilizando os softwares comerciais Ansoft Designer, Ansoft HFSS ambos da empresa Ansys e para efeito de compara??o foi utilizado o M?todo Iterativo das Ondas (WCIP). Para efeito de
valida??o foram constru?dos e medidos v?rios prot?tipos de antenas, FSS e filtros planares sendo poss?vel constatar uma excelente concord?ncia entre os resultados simulados e medidos
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For?a muscular respirat?ria, qualidade de vida e modula??o auton?mica da frequ?ncia card?aca na distrofia miot?nicaAra?jo, Thaise Lucena 22 July 2009 (has links)
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Previous issue date: 2009-07-22 / Background: The myotonic dystrophy (MD) is a multisystem neuromuscular disease that can affect the respiratory muscles and heart function, and cause impairment in quality of life. Objectives: Investigate the changes in respiratory muscle strength, health-related quality of life (HRQoL) and autonomic modulation heart rate (HR) in patients with MD. Methods: Twenty-three patients performed assessment of pulmonary function, sniff nasal inspiratory pressure (SNIP), the maximal inspiratory (MIP) and expiratory (MEP) pressure, and of HRQoL (SF-36 questionnaire). Of these patients, 17 underwent assessment of heart rate variability (HRV) at rest, in the supine and seated positions. Results: The values of respiratory muscle strength were 64, 70 and 80% of predicted for MEP, MIP, and SNIP, respectively. Significant differences were found in the SF-36 domains of physical functioning (58.7 ? 31,4 vs. 84.5 ? 23, p<0.01) and physical problems (43.4 ? 35.2 vs. 81.2 ? 34, p<0.001) when patients were compared with the reference values. Single linear regression analysis demonstrated that MIP explains 29% of the variance in physical functioning, 18% of physical problems and 20% of vitality. The HRV showed that from supine position to seated, HF decreased (0.43 x 0.30), and LF (0.57 x 0.70) and the LF/HF ratio (1.28 x 2.22) increased (p< 0.05). Compared to healthy persons, LF was lower in both male patients (2.68 x 2.99) and women (2.31 x 2.79) (p< 0.05). LF / HF ratio and LF were higher in men (5.52 x 1.5 and 0.8 x 0.6, p <0.05) and AF in women (0.43 x 0.21) (p< 0.05). There was positive correlation between the time of diagnosis and LF / HF ratio (r = 0.7, p <0.01). Conclusions: The expiratory muscle strength was reduced. The HRQoL was more impaired on the physical aspects and partly influenced by changes in inspiratory muscle strength. The HRV showed that may be sympathetic dysfunction in autonomic modulation of HR, although with normal adjustment of autonomic modulation during the change of posture. The parasympathetic modulation is higher in female patients and sympathetic tends to increase in patients with longer diagnosis / Introdu??o: A distrofia miot?nica (DM) ? uma doen?a neuromuscular multissist?mica que pode afetar a musculatura respirat?ria e a fun??o card?aca, e ocasionar preju?zos na qualidade de vida. Objetivos: Investigar as altera??es na for?a muscular respirat?ria, qualidade de vida relacionada ? sa?de (QVRS), e modula??o auton?mica da freq??ncia card?aca (FC) em pacientes com DM. M?todos: Foram avaliados 23 pacientes quanto ? fun??o pulmonar, press?o inspirat?ria nasal sniff (SNIP), press?es respirat?rias m?ximas (PIm?x e PEm?x), e QVRS (question?rio SF-36). Destes, 17 realizaram avalia??o da variabilidade da frequ?ncia card?aca (VFC) em repouso, nas posturas supina e sentada. Resultados: Os valores da for?a muscular respirat?ria foram de 64, 70 e 80%predito para PEm?x, PIm?x, e SNIP, respectivamente. Foi encontrada diminui??o significativa nos dom?nios do SF-36 capacidade funcional (58.7 ? 31,4 vs. 84.5 ? 23, p<0.01) e disfun??o f?sica (43.4 ? 35.2 vs. 81.2 ? 34, p<0.001) comparado a valores de refer?ncia. A an?lise de regress?o linear mostrou que a PIm?x explica 29% da vari?ncia na capacidade funcional, 18% na disfun??o f?sica e 20% na vitalidade. A VFC mostrou que, da postura supina para a sentada, o espectro AF diminuiu (0.43 x 0.30) e o espectro BF (0.57 x 0.70) e a raz?o BF/AF (1.28 x 2.22) aumentaram, com p<0.05. Comparado a valores de refer?ncia, BF foi inferior (p<0.05) tanto nos pacientes homens (2.68 x 2.99), como nas mulheres (2.31 x 2.79). A raz?o BF/AF e o espectro BF foram maiores nos homens (5.52 x 1.5 e 0.8 x 0.6), e o espectro AF, nas mulheres (0.43 x 0.21), com p<0.05. Houve correla??o significativa positiva entre tempo de diagn?stico e raz?o BF/AF (r= 0.7, p< 0.01). Conclus?es: Indiv?duos com DM t?m for?a muscular expirat?ria diminu?da. A QVRS mostrou-se mais prejudicada em rela??o a aspectos f?sicos e parcialmente influenciada por varia??es na for?a muscular inspirat?ria. Pode haver disfun??o simp?tica na modula??o auton?mica da FC, com ajuste normal da postura supina para a sentada. A modula??o parassimp?tica ? superior em pacientes mulheres e a modula??o simp?tica tende a aumentar nos pacientes com maior tempo de diagn?stico
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Revisitando o eletrocorticograma intra-operat?rio na epilepsia mesial do lobo temporal: relev?ncia das oscila??es de alta frequ?nciaSilva, Anderson Brito da 13 December 2013 (has links)
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Previous issue date: 2013-12-13 / Epilepsies are neurological disorders characterized by recurrent and spontaneous seizures
due to an abnormal electric activity in a brain network. The mesial temporal lobe epilepsy
(MTLE) is the most prevalent type of epilepsy in adulthood, and it occurs frequently
in association with hippocampal sclerosis. Unfortunately, not all patients benefit from
pharmacological treatment (drug-resistant patients), and therefore become candidates for
surgery, a procedure of high complexity and cost. Nowadays, the most common surgery is
the anterior temporal lobectomy with selective amygdalohippocampectomy, a procedure
standardized by anatomical markers. However, part of patients still present seizure after the
procedure. Then, to increase the efficiency of this kind of procedure, it is fundamental to
know the epileptic human brain in order to create new tools for auxiliary an individualized
surgery procedure.
The aim of this work was to identify and quantify the occurrence of epilepticform activity -such as interictal spikes (IS) and high frequency oscillations (HFO) - in electrocorticographic
(ECoG) signals acutely recorded during the surgery procedure in drug-resistant patients
with MTLE.
The ECoG recording (32 channels at sample rate of 1 kHz) was performed in the surface
of temporal lobe in three moments: without any cortical resection, after anterior temporal
lobectomy and after amygdalohippocampectomy (mean duration of each record: 10 min; N
= 17 patients; ethic approval #1038/03 in Research Ethic Committee of Federal University
of S?o Paulo). The occurrence of IS and HFO was quantified automatically by MATLAB
routines and validated manually. The events rate (number of events/channels) in each
recording time was correlated with seizure control outcome.
In 8 hours and 40 minutes of record, we identified 36,858 IS and 1.756 HFO. We observed
that seizure-free outcome patients had more HFO rate before the resection than non-seizure
free, however do not differentiate in relation of frequency, morphology and distribution of
IS. The HFO rate in the first record was better than IS rate on prediction of seizure-free
patients (IS: AUC = 57%, Sens = 70%, Spec = 71% vs HFO: AUC = 77%, Sens = 100%,
Spec = 70%). We observed the same for the difference of the rate of pre and post-resection
(IS: AUC = 54%, Sens = 60%, Spec = 71%; vs HFO: AUC = 84%, Sens = 100%, Spec =
80%). In this case, the algorithm identifies all seizure-free patients (N = 7) with two false
positives.
To conclude, we observed that the IS and HFO can be found in intra-operative ECoG
record, despite the anesthesia and the short time of record. The possibility to classify the
patients before any cortical resection suggest that ECoG can be important to decide the
use of adjuvant pharmacological treatment or to change for tailored resection procedure.
The mechanism responsible for this effect is still unknown, thus more studies are necessary
to clarify the processes related to it / As epilepsias s?o dist?rbios neurol?gicos caracterizados por crises espont?neas e recorrentes,
resultantes de uma atividade el?trica anormal de uma rede neural. Dentre os diferentes
tipos de epilepsia, a epilepsia mesial do lobo temporal (EMLT) ? a mais observada em
adultos, sendo frequentemente associada ? esclerose hipocampal. Infelizmente, nem todos
os pacientes s?o beneficiados pelo tratamento farmacol?gico (pacientes f?rmaco-resistentes).
Para estes sujeitos, uma alternativa ? a realiza??o de cirurgia, um procedimento de alta
complexidade e elevado custo. Atualmente, o procedimento mais realizado ? a lobectomia
temporal anterior com amigdalo-hipocampectomia seletiva, uma cirurgia padronizada por
marcos anat?micos. Entretanto, uma parcela dos pacientes continua a apresentar crises
incapacitantes ap?s o tratamento cir?rgico. Desta forma, para aumentar a efici?ncia deste
tipo de tratamento, ? fundamental a compreens?o do enc?falo humano epil?ptico com
vistas a se criar ferramentas que auxiliem na realiza??o de procedimentos individualizados.
O objetivo do presente trabalho foi identificar e quantificar a ocorr?ncia de atividade
epileptiforme - esp?culas interictais (EI) e oscila??es de alta frequ?ncia (OAF) - em registros
eletrocorticogr?ficos (ECoG) realizados durante procedimento cir?rgico em pacientes com
EMLT refrat?ria ao tratamento farmacol?gico.
Registros ECoG (32 canais a uma taxa de amostragem de 1 kHz) foram realizados na
superf?cie do lobo temporal em 3 momentos cir?rgicos: no c?rtex intacto, ap?s lobectomia
temporal anterior e ap?s amigdalo-hipocampectomia (dura??o m?dia de cada um desses
registros: 10 min; N=17 pacientes). A ocorr?ncia de EI e OAF foi quantificada automatica-mente, por meio de rotinas em MATLAB, e validadas manualmente. A taxa de ocorr?ncia
em cada um dos tempos cir?rgicos foi correlacionada com o resultado cir?rgico quanto ao
controle das crises, num seguimento de 2 anos.
De um total de 8 h e 40 min de registro, identificamos 36.858 EI e 1.756 OAF. Observamos
que os pacientes que ficaram livres de crises no p?s-operat?rio apresentaram maior quanti-dade de OAF antes da cirurgia do que aqueles que continuaram a ter crises; por?m, n?o
diferiram quanto a frequ?ncia, morfologia e distribui??o de EI. A ocorr?ncia de OAF no
registro basal apresentou melhor desempenho que as EI na previs?o do controle total das
crises no p?s-operat?rio (EI: AUC = 57%, S = 71% , E = 70% vs OAF: AUC = 77%, S =
100%, E=70%). O mesmo foi observado com a varia??o da ocorr?ncia entre os momentos
pr?- e p?s-ressec??o (EI: AUC = 54%, S = 71%, E = 60% vs OAF: AUC = 84%, S =
100%, E = 80%). Nesse caso, o classificador foi capaz de identificar todos os pacientes
livres de crises (N = 7) , apresentando apenas dois falsos positivos.
Desta forma, podemos concluir que as OAF, juntamente com as EI, podem ser encontradas
no registro ECoG intra-operat?rio, mesmo na presen?a de anest?sicos e em uma curta
sess?o de registro. Al?m disso, a observa??o de que a ocorr?ncia desses eventos no in?cio
da cirurgia permite classificar o paciente quanto ao progn?stico cir?rgico abre caminho
para aplicar o ECoG intra-operat?rio, por exemplo, na decis?o sobre o uso de tratamento
farmacol?gico adjuvante ou da convers?o para ressec??es individualizadas. No entanto,
o mecanismo respons?vel por esse efeito ainda ? desconhecido, logo novos estudos s?o
necess?rios para melhor esclarec?-lo
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