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1
Fung, Jimmy Jr. "Parameter Identification of Nonlinear Systems Using Perturbation Methods and Higher-Order Statistics." Thesis, Virginia Tech, 1998. http://hdl.handle.net/10919/36921.
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A parametric identification procedure is proposed that combines
the method of multiple scales and higher-order statistics to
efficiently and accurately model nonlinear
systems. A theoretical background for the method of
multiple scales and higher-order
statistics is given.
Validation of the procedure is performed
through applying it to numerical simulations of two
nonlinear systems. The results show how the procedure can
successfully characterize the system damping and nonlinearities and
determine the corresponding parameters.
The procedure is then applied to experimental measurements from
two structural systems, a
cantilevered beam and a three-beam frame. The results show that
quadratic damping should be accounted for in both systems.
Moreover, for the three-beam frame, the parametric excitation is
much more important than the direct excitation.
To show the flexibility of the
procedure, numerical simulations of ship motion under parametric
excitation are used to determine nonlinear parameters govening the
relation between pitch, heave, and roll motions. The results show
a high level of agreement between the numerical simulation and the
mathematical model with the identified parameters.Master of Science
2
Negrete, Regagnon Pedro. "Bispectral imaging in astronomy." Thesis, Imperial College London, 1995. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.307433.
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Fackrell, Justin W. A. "Bispectral analysis of speech signals." Thesis, University of Edinburgh, 1997. http://hdl.handle.net/1842/1384.
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Techniques which utilise a signal's Higher Order Statistics (HOS) can reveal information about non-Gaussian signals and nonlinearities which cannot be obtained using conventional (second-order) techniques. This information may be useful in speech processing because it may provide clues about how to construct new models of speech production which are better than existing models. There has been a recent surge of interest in the application of HOS techniques to speech processing, but this has been handicapped by a lack of understanding of what the HOS properties of speech signals are. Without this understanding the HOS information which is in speech signals can not be efficiently utilised. This thesis describes an investigation into the use of HOS techniques, in particular the third-order frequency domain measure called the bispectrum, to speech signals. Several issues relating to bispectral speech analysis are addressed, including nonlinearity detection, pitch-synchronous analysis, estimation criteria and stationarity. A flaw is identified in an existing algorithm for detecting quadratic nonlinearities, and a new detector is proposed which has better statistical properties. In addition, a new algorithm is developed for estimating the normalised bispectrum of signals contaminated by transient noise. Finally the tools developed in the study are applied to a specially constructed database of continuant speech sounds. The results are consistent with the hypothesis that speech signals do not exhibit quadratic nonlinearity.
4
Jin, Song. "Bispectral reconstruction of speckle-degraded images /." Online version of thesis, 1992. http://hdl.handle.net/1850/11230.
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Sundaramoorthy, Gopalakrishnan. "Improved techniques for bispectral reconstruction of signals /." Online version of print, 1990. http://hdl.handle.net/1850/11456.
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Partanen, Mikko. "Anestesidjup med hjälp av Bispectral Index : litteraturstudie." Thesis, Uppsala universitet, Institutionen för folkhälso- och vårdvetenskap, 2012. http://urn.kb.se/resolve?urn=urn:nbn:se:uu:diva-272182.
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Deschk, Mauricio. "Índice biespectral, efeitos hemodinâmicos e respiratórios da infusão contínua de propofol associado ou não ao fentanil em bezerros." Botucatu, 2015. http://hdl.handle.net/11449/140258.
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Orientador: Celso Antônio RodriguesCoorientador: Paulo Sergio Patto dos Santos
Banca: Stélio Pacca Loureiro Luna
Banca: Antônio José de Araújo Aguiar
Banca: Lídia Mitsuko Matsubara
Banca: Juan Carlos Duque Moreno
Resumo: O estudo teve por objetivo avaliar o índice biespectral e os efeitos hemodinâmicos, respiratórios e hemogasométricos da infusão contínua de propofol associado ou não ao fentanil em bezerros. Foram utilizados oito animais machos entre seis e doze meses de idade, holandeses, com massa corporal média de 123 ± 18 kg. Todos os animais participaram de ambos os grupos, respeitando-se sempre um intervalo mínimo de uma semana entre uma anestesia e outra, os bezerros foram aleatoriamente distribuídos entre os grupos. Os animais foram induzidos à anestesia com propofol na dose de 5 mg/kg; IV, grupo controle (GP) ou propofol 4 mg/kg associado ao fentanil 0,001 mg/kg; IV, grupo fentanil (GF) e posicionados em decúbito lateral direito, onde permaneceram respirando espontaneamente ar ambiente. Ato contínuo, a manutenção anestésica foi realizada pela infusão contínua de propofol na taxa de 0,6 mg/kg/minuto; IV, associado ou não à infusão de fentanil 0,001 mg/kg/hora.Em ambos os grupos os fármacos foram administrados por meio de bomba de infusão durante 60 minutos. A mensuração das variáveis hemodinâmicas (FC, PAS, PAD, PAM, DC, PVC, PAPm, PAPOm, IC, IS, IRVS e IRVP), respiratórias (ETCO2, f, SpO2, VTE e VME), hemogasométricas (PaO2, PaCO2, SaO2, DB, pH e HCO3-) e indice bispectral (BIS, IQS e EMG) foi feita antes da indução anestésica (MB), e 15, 30,45 e 60 minutos após o início da infusão contínua dos fármacos (M15, M30, M45 e M60, respectivamente). Os parâmetros hemodinâmicos mantiveram-se estáveis durante o período de avalição, não foram observadas diferenças significativas entre os grupos nas variáveis respiratórias ou no BIS, porém, todos os animais apresentaram depressão respiratória e acidose. Com a infusão de propofol associado ou não ao fentanil obteve-se manutenção satisfatória dos parâmetros hemodinâmicos com depressão respiratória, indicando, portanto, a necessidade do emprego de ventilação...
Abstract: The aim of this study was to evaluate the bispectral index and hemodynamic, respiratory and blood gas effects of continuous infusion of propofol with or without fentanyl in calves. Eight animals were used, with six to 12 months old, male Holstein calves, with an average weight of 123 ± 18 kg. All animals participated in both groups, respecting always a minimum interval of one week between the anesthetic procedures, the calves were randomly distributed between groups. They were induced to anesthesia with propofol at a dose of 5 mgkg-1 IV control group (GP) or propofol 4 mg kg-1 associated with fentanyl 0.001mgkg-1 IV fentanyl group (GF) and positioned in right lateral decubitus, where remained spontaneously breathing room air. Subsequently, the Anesthesia was maintained by continuous infusion of propofol at the rate of 0.6 mg kg-1 min-1 IV, with or without the infusion of fentanyl 0.001mg kg-1 hour-1. In both groups, drugs were administered through an infusion pump over 60 minutes. The measurements of hemodynamic parameters (HR, SAP, DAP, MAP, CO, CVP, mPAP, mPAPO, CI, SI, SVRI and PVRI), respiratory (ETCO2, f, SpO2,VME and VTE), blood gas(PaO2, PaCO2, SaO2, DB, pHandHCO3-) and bispectral index (BIS, SQI and EMG) were evaluated before anesthesia induction(MB), 15, 30, 45 and 60 minutes after the beginning of continuous infusion of drugs (M15, M30, M45 and M60, respectively). Hemodynamic parameters remained stable during the evaluate on period, no significant differences were observed between the groups in the respiratory variables and BIS, however, all animals presented respiratory acidosis. With the infusion of propofol associated or not with fentanyl the maintenance of the hemodynamic parameters was satisfactory with respiratory acidosis indicating, therefore, the use of mechanical ventilation
Doutor
8
Deschk, Mauricio [UNESP]. "Índice biespectral, efeitos hemodinâmicos e respiratórios da infusão contínua de propofol associado ou não ao fentanil em bezerros." Universidade Estadual Paulista (UNESP), 2015. http://hdl.handle.net/11449/140258.
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000866936.pdf: 1220294 bytes, checksum: 4c57fe16155fd1456befca08e06dd4e1 (MD5)Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)
O estudo teve por objetivo avaliar o índice biespectral e os efeitos hemodinâmicos, respiratórios e hemogasométricos da infusão contínua de propofol associado ou não ao fentanil em bezerros. Foram utilizados oito animais machos entre seis e doze meses de idade, holandeses, com massa corporal média de 123 ± 18 kg. Todos os animais participaram de ambos os grupos, respeitando-se sempre um intervalo mínimo de uma semana entre uma anestesia e outra, os bezerros foram aleatoriamente distribuídos entre os grupos. Os animais foram induzidos à anestesia com propofol na dose de 5 mg/kg; IV, grupo controle (GP) ou propofol 4 mg/kg associado ao fentanil 0,001 mg/kg; IV, grupo fentanil (GF) e posicionados em decúbito lateral direito, onde permaneceram respirando espontaneamente ar ambiente. Ato contínuo, a manutenção anestésica foi realizada pela infusão contínua de propofol na taxa de 0,6 mg/kg/minuto; IV, associado ou não à infusão de fentanil 0,001 mg/kg/hora.Em ambos os grupos os fármacos foram administrados por meio de bomba de infusão durante 60 minutos. A mensuração das variáveis hemodinâmicas (FC, PAS, PAD, PAM, DC, PVC, PAPm, PAPOm, IC, IS, IRVS e IRVP), respiratórias (ETCO2, f, SpO2, VTE e VME), hemogasométricas (PaO2, PaCO2, SaO2, DB, pH e HCO3-) e indice bispectral (BIS, IQS e EMG) foi feita antes da indução anestésica (MB), e 15, 30,45 e 60 minutos após o início da infusão contínua dos fármacos (M15, M30, M45 e M60, respectivamente). Os parâmetros hemodinâmicos mantiveram-se estáveis durante o período de avalição, não foram observadas diferenças significativas entre os grupos nas variáveis respiratórias ou no BIS, porém, todos os animais apresentaram depressão respiratória e acidose. Com a infusão de propofol associado ou não ao fentanil obteve-se manutenção satisfatória dos parâmetros hemodinâmicos com depressão respiratória, indicando, portanto, a necessidade do emprego de ventilação...
The aim of this study was to evaluate the bispectral index and hemodynamic, respiratory and blood gas effects of continuous infusion of propofol with or without fentanyl in calves. Eight animals were used, with six to 12 months old, male Holstein calves, with an average weight of 123 ± 18 kg. All animals participated in both groups, respecting always a minimum interval of one week between the anesthetic procedures, the calves were randomly distributed between groups. They were induced to anesthesia with propofol at a dose of 5 mgkg-1 IV control group (GP) or propofol 4 mg kg-1 associated with fentanyl 0.001mgkg-1 IV fentanyl group (GF) and positioned in right lateral decubitus, where remained spontaneously breathing room air. Subsequently, the Anesthesia was maintained by continuous infusion of propofol at the rate of 0.6 mg kg-1 min-1 IV, with or without the infusion of fentanyl 0.001mg kg-1 hour-1. In both groups, drugs were administered through an infusion pump over 60 minutes. The measurements of hemodynamic parameters (HR, SAP, DAP, MAP, CO, CVP, mPAP, mPAPO, CI, SI, SVRI and PVRI), respiratory (ETCO2, f, SpO2,VME and VTE), blood gas(PaO2, PaCO2, SaO2, DB, pHandHCO3-) and bispectral index (BIS, SQI and EMG) were evaluated before anesthesia induction(MB), 15, 30, 45 and 60 minutes after the beginning of continuous infusion of drugs (M15, M30, M45 and M60, respectively). Hemodynamic parameters remained stable during the evaluate on period, no significant differences were observed between the groups in the respiratory variables and BIS, however, all animals presented respiratory acidosis. With the infusion of propofol associated or not with fentanyl the maintenance of the hemodynamic parameters was satisfactory with respiratory acidosis indicating, therefore, the use of mechanical ventilation
FAPESP: 2013/09469-1
9
Lindholm, Maj-Lis. "Utility of bispectral index (BIS) monitoring during general anesthesia." Stockholm, 2009. http://diss.kib.ki.se/2009/978-91-7409-697-2/.
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Cole, Zachary K. "Radar target recognition using bispectrum correlation." Thesis, Monterey, Calif. : Naval Postgraduate School, 2007. http://bosun.nps.edu/uhtbin/hyperion-image.exe/07Jun%5FCole.pdf.
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Thesis (M.S. in Physics)--Naval Postgraduate School, June 2007.Thesis Advisor(s): Brett Borden. "June 2007." Description based on title screen as viewed on July 31, 2007. Includes bibliographical references (p. 79-80). Also available in print.
11
Pike, Cameron M. "Multipath signal detection using the bispectrum." Ohio : Ohio University, 1990. http://www.ohiolink.edu/etd/view.cgi?ohiou1183467926.
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Coleman, Robin Marie. "Étude de la relation entre l'indice bispectral et la douleur." Mémoire, Université de Sherbrooke, 2012. http://hdl.handle.net/11143/6287.
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L'évaluation de la douleur est un défi de taille chez la clientèle incapable de communiquer verbalement à l'unité de soins intensifs (USI). Les outils d'évaluation présentement utilisés par les cliniciens pour détecter la douleur chez les patients sous sédation et ventilés mécaniquement, tels que les signes vitaux (SV) et les outils comportementaux, présentent des lacunes limitant leur utilisation dans ce contexte. Les signes vitaux ne sont pas spécifiques à la douleur et les comportements peuvent être influencés par plusieurs facteurs. Des études récentes suggèrent que la valeur de l'indice bispectral (BIS), une mesure physiologique de l'activité corticale, pourrait augmenter lors de stimuli nociceptif. Le premier objectif de ce mémoire était d'effectuer une revue de la littérature scientifique sur l'utilisation des mesures physiologiques, plus particulièrement le BIS dans l'évaluation du nociception chez les patients incapables de communiquer à l'USI. Cette revue de la littérature nous a permis de découvrir certaines variables possiblement confondantes devant être contrôlées lors de la poursuite des études sur la relation entre le BIS et le nociception. De plus, elle a pèrmis d'orienter notre deuxième objectif visant à étudier la relation entre le BIS et le nociception. Le deuxième objectif de ce mémoire était d'effectuer une étude quasi-expérimentale avec mesures avant-après, intra sujet. Cette étude visait à examiner les changements du BIS en réponse à des stimuli nociceptifs expérimentaux auprès de trente participants sous anesthésie générale. Au bloc opératoire (BO), une thermode était installée au niveau de l'avant-bras du participant afin d'induire un stimuli nociceptif thermique d'intensité modérée et sévère. Le BIS a été observé pendant l'exposition aux stimuli nociceptifs après l'induction d'anesthésie générale, avant la chirurgie. Une augmentation significative du BIS a été observée pendant les stimuli nociceptifs de 40/100 et de 70/100. La courbe ROC (Receiver Operating Characteristic Curve) a démontré une sensibilité (Se) de 40,0 % et une spécificité (Sp) de 73,3 % avec un BIS > 45, dans la distinction des stimuli d'intensité modérée et sévère. En conclusion, le BIS a augmenté en réponse à un stimulus nociceptif expérimental de 40/100 et de 70/100. La Se et la Sp du BIS ne supportent pas l'utilisation du BIS pour la distinction de différentes intensités de douleur dans le contexte de sédation profonde au BO. Néanmoins, son utilisation, devrait être davantage étudiée auprès de la clientèle moins profondément sédationnée à l'USI.
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Jouny, Ismail. "Bispectral analysis of radar signals with application to target classification /." The Ohio State University, 1990. http://rave.ohiolink.edu/etdc/view?acc_num=osu1487683049375875.
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Flowers, John. "Quantifiying the Depth of Oral Sedation Using Bispectral Index Monitoring." VCU Scholars Compass, 2008. http://scholarscompass.vcu.edu/etd/1511.
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Purpose: To determine whether Bispectral Index Monitoring is an effective tool for quantifying sedation depth after the administration of oral drug regimens in children.Methods: This retrospective study reviewed the charts of 75 children who received oral conscious sedation for dental treatment. Data collected from the chart included; 1) BIS values at 5 minute intervals and at five critical events: pre-operative, local anesthesia delivery, rubber dam placement (if utilized), during operative treatment, and postoperatively, 2) behavior ratings at the five critical events and an overall behavior assessment, 3) treatment data, and 4) demographic data. Results: The mean BIS value for orally sedation children in this study was 84.53 (SD = 5.76). The mean overall sedation assessment was 2.04 (SD = 1.16). No significant correlation was found between BIS values and behavioral ratings.Conclusion: The BIS monitor provided limited information regarding the depth of sedation in children undergoing oral sedation for dental treatment.
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Fergusson, J. "Primordial non-Gaussianity and the CMB bispectrum." Thesis, University of Cambridge, 2009. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.598987.
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In this thesis we will present a comprehensive set of formalisms for comparing, evolving, and constraining primordial non-Gaussian models through the CMB bispectrum. First, we introduce the idea of a shape function for characterising the primordial non-Gaussianity. The shape function can also be used to construct a correlator between the models which we use to group the space of possible models into four main classes: equilateral, squeezed, flattened, and scale dependent. Next, we use a common property of the shape function to create a method for calculating, without approximation, the CMB bispectrum from a general primordial model. There are two techniques we use to speed up the calculation. The first is to use the flat sky approximation for large l, and the second is to exploit the smoothness of the reduced bispectrum to calculate the bispectrum first on a sparse grid then interpolate to obtain the remaining points. We then discuss methods for calculating estimators by decomposing the bispectrum, either today or at primordial times, into the product of eigenmodes. First we deal with the primordial bispectrum and describe how the decomposition can be used to both constrain primordial models and to estimate the primordial bispectrum from observations. Then we repeat the analysis for the CMB bispectrum and describe how this process can be used to constrain models, but this time allowing for the inclusion of late time effects. It also presents a method for generating maps with an arbitrary bispectrum and power spectrum.
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Yankelevich, Victoria [Verfasser]. "Cosmology with the galaxy bispectrum / Victoria Yankelevich." Bonn : Universitäts- und Landesbibliothek Bonn, 2019. http://d-nb.info/1200020030/34.
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Ambrogi, Federico. "Bispectrum of cosmological models with massive neutrinos." Master's thesis, Alma Mater Studiorum - Università di Bologna, 2014. http://amslaurea.unibo.it/7429/.
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Uno dei più importanti campi di ricerca che coinvolge gli astrofisici è la comprensione della Struttura a Grande Scala dell'universo. I principi della Formazione delle Strutture sono ormai ben saldi, e costituiscono la base del cosiddetto "Modello Cosmologico Standard".
Fino agli inizi degli anni 2000, la teoria che spiegava con successo le proprietà statistiche dell'universo era la cosiddetta "Teoria Perturbativa Standard". Attraverso simulazioni numeriche e osservazioni di qualità migliore, si è evidenziato il limite di quest'ultima teoria nel descrivere il comportamento dello spettro di potenza su scale oltre il regime lineare.
Ciò spinse i teorici a trovare un nuovo approccio perturbativo, in grado di estendere la validità dei risultati analitici. In questa Tesi si discutono le teorie "Renormalized Perturbation Theory"e"Multipoint Propagator".
Queste nuove teorie perturbative sono la base teorica del codice BisTeCca, un codice numerico originale che permette il calcolo dello spettro di potenza a 2 loop e del bispettro a 1 loop in ordine perturbativo. Come esempio applicativo, abbiamo utilizzato BisTeCca per l'analisi dei bispettri in modelli di universo oltre la cosmologia standard LambdaCDM, introducendo una componente di neutrini massicci.
Si mostrano infine gli effetti su spettro di potenza e bispettro, ottenuti col nostro codice BisTeCca, e si confrontano modelli di universo con diverse masse di neutrini.
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Pettinari, Guido Walter. "The intrinsic bispectrum of the Cosmic Microwave Background." Thesis, University of Portsmouth, 2013. https://researchportal.port.ac.uk/portal/en/theses/the-intrinsic-bispectrum-of-the-cosmic-microwave-background(ce62a4e8-625f-4c84-9e0c-821df12cba10).html.
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Cosmology, intended as the study of the origin and evolution of the Universe and its components, has advanced from being a philosophical discipline to a data-driven science. Much of this progress was achieved in the last few decades thanks to the wealth of cosmological data from Earth and space-based experiments. The abundance of observational constraints has considerably narrowed the space for theoretical speculation, to the point that now most of the cosmological community agrees on a standard model of cosmology. A crucial assumption of this model is that the structure observed in the Universe, such as planets, stars and galaxies, can be ultimately traced back to tiny density perturbations in the early Universe. Therefore, a huge theoretical and experimental effort is being made by cosmologists and particle physicists to gain insight of the mechanism of generation of these primordial fluctuations, which remains still largely unknown. The bispectrum of the cosmic microwave background (CMB) has been recently recognised as a powerful probe of this mechanism, as it is sensitive to the non-Gaussian features in the seed fluctuations. To access this information, however, it is crucial to model the non-linear evolution of the CMB between the formation of the initial fluctuations and its observation, which results in the emergence of an intrinsic bispectrum. The main purpose of this thesis is to quantify the intrinsic bispectrum and compute the bias it induces on the primordial signal. To do so, we develop SONG, a new and efficient code for solving the second-order Einstein-Boltzmann equations, and use it to estimate the intrinsic CMB non-Gaussianity arising from the non-linear evolution of density perturbations. The full calculation involves contributions from recombination and less tractable ones from terms integrated along the line of sight. We investigate the bias that this intrinsic bispectrum implies for searches of primordial non-Gaussianity. We find that the inclusion or omission of certain line of sight terms can make a large impact. When including all physical effects but lensing and time-delay, we find that the contamination from the intrinsic bispectrum generally leads to a small bias in the estimates of non-Gaussianity, which is good news for the prospect of using cosmic microwave background data to probe primordial non-Gaussianity. The intrinsic non-Gaussianity can be searched for directly, using the predicted signal as a template; our calculations suggest this signal is just beyond what is possible with the Planck CMB survey, with a signal-to-noise rising to unity only for an angular resolution of `max = 3000.
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Vieira, Elayne Francis Leal Leite. "Uso do índice bispectral como monitor de perfusão encefálica em procedimentos neuroendovasculares." reponame:Repositório Institucional da UnB, 2016. http://repositorio.unb.br/handle/10482/22364.
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Dissertação (mestrado)—Universidade de Brasília, Faculdade de Medicina, Programa de Pós-Graduação em Ciências Médicas, 2016.Submitted by Fernanda Percia França (fernandafranca@bce.unb.br) on 2016-11-21T19:05:16Z No. of bitstreams: 1 2016_ElayneFrancisLealLeiteVieira.pdf: 1581348 bytes, checksum: 6e3f6250bbce4068157c5d6ccd5c1a2f (MD5)
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Justificativa: O tratamento endovascular das doenças neurológicas é realizado através de técnica minimamente invasiva e vem evoluindo rapidamente nas últimas décadas. Apesar disto, a neurocirurgia endovascular não é um procedimento isento de intercorrências. Existem várias formas de se monitorar a função cerebral no intra-operatório, no entanto, estudos sugerem que, apesar de não ter sido desenhado inicialmente para tal, o Índice Biespectral (BIS) pode ter utilidade na detecção da isquemia cerebral, associado às vantagens de ser não-invasivo e de fácil interpretação. A necessidade da monitorização da perfusão encefálica nesses procedimentos se justifica pela possibilidade de detecção precoce de eventos adversos, sua prevenção, e mesmo, a redução do tempo para reintervenção. Objetivos: Verificar a utilidade do BIS como monitor da perfusão cerebral. Métodos: Os valores de BIS foram observados inicialmente, antes da indução anestésica, com pacientes despertos, no transoperatório e no momento do despertar, e foram confrontados com a avaliação clínica da consciência do paciente através de escalas de sedação/coma conhecidas. Resultados: A respeito do tipo de procedimento, houve 17 embolizações de aneurismas (41,5%) e 13 embolizações de malformações arteriovenosas (31,7%); outros procedimentos menos frequentes foram responsáveis pelos 26,8% restantes. Ocorreram 3 complicações transoperatórias (7,3%), todas em embolizações de aneurismas. Todas as complicações foram sinalizadas com alterações nos valores do BIS no transoperatório (p=0,043).Conclusões: Na população do presente estudo, o BIS se mostrou um monitor sensível da perfusão encefálica, embora pouco específico. Estudos adicionais e com populações maiores são necessários para confirmar os achados.
Purpouse: Endovascular treatment of neurological diseases through minimally invasive techniques has advanced rapidly in recente decades. Nevertheless, endovascular neurosurgery is not free of complications. Several methods are available for intraoperative monitoring of brain function. Studies suggest that, although it was not designed for this purpouse, the bispectral index (BIS) may be a useful, non-invasive and readily interpretable method for detection of cerebral ischemia. Monitoring of cerebral perfusion during such procedures is justified by the possibility of early detection and prevention of adverse events, and perhaps even of reducing the time to reintervention when necessary. Objetives: To acess the utility of BIS for cerebral perfusion monitoring. Methods: BIS values were recorded at baseline (before induction of anaesthesia), intraoperatively, and at the time of emergence from anaesthesia, and were compared to clinical assessments of level of consciousness using established sedation and coma scales. Results: Regarding procedure type, there were 17 aneurysm embolisations (41.5%) and 13 arteriovenous malformation embolisations (31.7%); other, less frequent procedures accounted for the remaining 26.8%. Three patients, all of whom were undergoing aneurysm embolisation, experienced intraoperative complications (7.3%). All intraoperative complications were heralded by intraoperative changes in BIS (p=0.043) Conclusions: In the population of the present study, BIS monitoring was a sensitive, although not very specific, marker of cerebral perfusion. Further studies with larger populations are needed to confirm these findings.
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Deschk, Mauricio. "Índice bispectral, efeitos hemodinâmicos e respiratórios da infusão contínua de diferentes taxas de propofol em bezerros /." Araçatuba : [s.n.], 2013. http://hdl.handle.net/11449/99631.
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Resumo: O estudo teve por objetivo avaliar o índice bispectral, efeitos hemodinâmicos e respiratórios da infusão contínua de diferentes taxas de propofol em bezerros. Foram utilizados 8 animais de seis a 12 meses de idade, holandeses, pesando de 84 a 124 kg. Os animais foram induzidos à anestesia com propofol na dose de 5 mg/kg IV e posicionados em decúbito lateral direito, onde permaneceram respirando espontaneamente ar ambiente. Ato contínuo, a manutenção anestésica foi realizada pela infusão contínua de propofol, administrado por meio de bomba de infusão em duas diferentes taxas 0,6 mg/kg/minuto IV (G06) e 0,8 mg/kg/minuto IV, (G08) durante 60 minutos. Os 8 animais foram anestesiados duas vezes, com uma semana de intervalo entre uma anestesia e outra. As variáveis hemodinâmicas (FC, PAS, PAD, PAM, DC, PVC, PAPm, PAPOm, IC, IS, IRVS e IRVP), respiratórias (ETCO, f, SpO, 2 2 V, V, e PFI), hemogasométricas (PaO, PaCO, SaO, DB, pH e HCO -) e TE ME 2 2 2 3 índice bispectral (BIS, EMG e IQS) foram avaliadas antes da indução anestésica (M ), e 15, 30, 45 e 60 minutos após o início da infusão contínua do B propofol (M15, M30, M45 e M60, respectivamente). Já a colheita das amostras para a dosagem plasmática do propofol foi realizada aos M15, M30, M45 e M60 minutos durante a infusão contínua do propofol e as demais colheitas foram realizadas após o termino da infusão com intervalos de 10 minutos por um período de 50 minutos (M70, M80, M90, M100 e M110 respectivamente). A infusão contínua de diferentes taxas de propofol não alterou as variáveis do BIS ao longo do tempo durante a infusão, também não causou alterações hemodinâmicas importantes, porém o G08 apresentou acidose respiratória indicando uso de ventilação controladaAbstract: The aim of this study was to evaluate the bispectral index, hemodynamic and respiratory effects of continuous infusion of different rates of propofol in calves. Eight Holstein calves aging between six and 12 months and weighing 84-124 kg were used. They were induced to anesthesia with propofol at a dose of 5 mg / kg IV and positioned in right lateral recumbency, where they remained spontaneously breathing ambient air. Immediately thereafter, the anesthesia was maintained by continuous infusion of propofol administered with the aid of an infusion pump in two different rates 0.6 mg / kg / minute, IV (G06) and 0.8 mg / kg / minute, IV, (G08), during 60 minutes. The 8 animals were anesthetized twice, with one-week interval between anesthesia. The measurements of hemodynamic (HR, SAP, DAP, MAP, CO, CVP, mPAP, mPAPO, CI, SI, SVRI and PVRI), and respiratory parameters (ETCO2, f, SpO2, VTE, VME, and PFI), arterial blood gases (PaO2, PaCO2, SaO2, BE, pH and HCO3-) and bispectral index (BIS, EMG and SQI) were assessed before induction of anesthesia (MB), and 15, 30, 45 and 60 minutes after the start of continuous infusion of propofol (M15 , M30, M45 and M60, respectively). Sampling to measure plasma propofol was performed M15, M30, M45 and M60 minutes during continuous infusion of propofol and other samples were harvested after the end of infusion with 10-minute intervals during a period of 50 minutes (M70, M80, M90, M100 and M110 respectively). Continuous infusion of propofol at different rates did not alter the variables BIS over time and also did not cause significant hemodynamic changes, but the G08 had respiratory acidosis suggesting the use of controlled ventilation
Orientador: Paulo Sergio Patto dos Santos
Banca: Valéria Nobre Leal de Souza Oliva
Banca: Simone Bopp
Mestre
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Deschk, Mauricio [UNESP]. "Índice bispectral, efeitos hemodinâmicos e respiratórios da infusão contínua de diferentes taxas de propofol em bezerros." Universidade Estadual Paulista (UNESP), 2013. http://hdl.handle.net/11449/99631.
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deschk_m_me_araca.pdf: 1043151 bytes, checksum: 98566e693ca4c0ab17fc2c38ada17bfc (MD5)Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)
O estudo teve por objetivo avaliar o índice bispectral, efeitos hemodinâmicos e respiratórios da infusão contínua de diferentes taxas de propofol em bezerros. Foram utilizados 8 animais de seis a 12 meses de idade, holandeses, pesando de 84 a 124 kg. Os animais foram induzidos à anestesia com propofol na dose de 5 mg/kg IV e posicionados em decúbito lateral direito, onde permaneceram respirando espontaneamente ar ambiente. Ato contínuo, a manutenção anestésica foi realizada pela infusão contínua de propofol, administrado por meio de bomba de infusão em duas diferentes taxas 0,6 mg/kg/minuto IV (G06) e 0,8 mg/kg/minuto IV, (G08) durante 60 minutos. Os 8 animais foram anestesiados duas vezes, com uma semana de intervalo entre uma anestesia e outra. As variáveis hemodinâmicas (FC, PAS, PAD, PAM, DC, PVC, PAPm, PAPOm, IC, IS, IRVS e IRVP), respiratórias (ETCO, f, SpO, 2 2 V, V, e PFI), hemogasométricas (PaO, PaCO, SaO, DB, pH e HCO -) e TE ME 2 2 2 3 índice bispectral (BIS, EMG e IQS) foram avaliadas antes da indução anestésica (M ), e 15, 30, 45 e 60 minutos após o início da infusão contínua do B propofol (M15, M30, M45 e M60, respectivamente). Já a colheita das amostras para a dosagem plasmática do propofol foi realizada aos M15, M30, M45 e M60 minutos durante a infusão contínua do propofol e as demais colheitas foram realizadas após o termino da infusão com intervalos de 10 minutos por um período de 50 minutos (M70, M80, M90, M100 e M110 respectivamente). A infusão contínua de diferentes taxas de propofol não alterou as variáveis do BIS ao longo do tempo durante a infusão, também não causou alterações hemodinâmicas importantes, porém o G08 apresentou acidose respiratória indicando uso de ventilação controlada
The aim of this study was to evaluate the bispectral index, hemodynamic and respiratory effects of continuous infusion of different rates of propofol in calves. Eight Holstein calves aging between six and 12 months and weighing 84-124 kg were used. They were induced to anesthesia with propofol at a dose of 5 mg / kg IV and positioned in right lateral recumbency, where they remained spontaneously breathing ambient air. Immediately thereafter, the anesthesia was maintained by continuous infusion of propofol administered with the aid of an infusion pump in two different rates 0.6 mg / kg / minute, IV (G06) and 0.8 mg / kg / minute, IV, (G08), during 60 minutes. The 8 animals were anesthetized twice, with one-week interval between anesthesia. The measurements of hemodynamic (HR, SAP, DAP, MAP, CO, CVP, mPAP, mPAPO, CI, SI, SVRI and PVRI), and respiratory parameters (ETCO2, f, SpO2, VTE, VME, and PFI), arterial blood gases (PaO2, PaCO2, SaO2, BE, pH and HCO3-) and bispectral index (BIS, EMG and SQI) were assessed before induction of anesthesia (MB), and 15, 30, 45 and 60 minutes after the start of continuous infusion of propofol (M15 , M30, M45 and M60, respectively). Sampling to measure plasma propofol was performed M15, M30, M45 and M60 minutes during continuous infusion of propofol and other samples were harvested after the end of infusion with 10-minute intervals during a period of 50 minutes (M70, M80, M90, M100 and M110 respectively). Continuous infusion of propofol at different rates did not alter the variables BIS over time and also did not cause significant hemodynamic changes, but the G08 had respiratory acidosis suggesting the use of controlled ventilation
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Jolicoeur, Sheean. "The observed bispectrum for SKA and other galaxy surveys." University of the Western Cape, 2019. http://hdl.handle.net/11394/6792.
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Philosophiae Doctor - PhDNext-generation galaxy surveys will usher in a new era of high precision cosmology. They will increasingly rely on the galaxy bispectrum to provide improved constraints on the key parameters of a cosmological model to percent level or even beyond. Hereby, it is imperative to understand the theory of the galaxy bispectrum to at least the same level of precision. By this, we mean to include all the general relativistic projection effects arising from observing on the past lightcone, which still remains a theoretical challenge. This is because unlike the galaxy power spectrum, the galaxy bispectrum requires these lightcone corrections at second-order. For the rst time, this PhD project looks at all the local relativistic lightcone e ects in the galaxy bispectrum for a at Friedmann-Lemaitre-Robertson-Walker Universe, giving full details on the second-order scalars, vectors and tensors. These lightcone effects are mostly Doppler and gravitational potential contributions. The vector and tensor modes are induced at second order by scalars. We focus on the squeezed shapes for the monopole of the galaxy bispectrum because non-Gaussianity of the local form shows high signatures for these triangular con gurations. In the exact squeezed limit, the contributions from the vectors and tensors vanish. These relativistic projection effects, if not included in the analysis of observations, can be mistaken for primordial non-Gaussianity. For future surveys which will probe equality scales and beyond, all the relativistic corrections will need to be considered for an accurate measurement of primordial non-Gaussianity.
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Pearson, Ruth. "CMB lensing : polarization, large-scale structure and the primordial bispectrum." Thesis, University of Sussex, 2014. http://sro.sussex.ac.uk/id/eprint/48418/.
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Gravitational lensing of photons in the Cosmic Microwave Background (CMB) can be described by an integrated potential along the line of sight, the CMB lensing potential. Covariances in maps of the CMB are generated by the lensing effect, and are used to reconstruct the lensing potential itself, which is a useful probe of the matter distribution. The CMB lensing potential has been measured to high significance with CMB temperature data. However, signal to noise for lensing reconstruction from CMB polarization data is expected to be much better due to the presence of the lensing B-mode. Upcoming data from ground based CMB polarization instruments will provide high resolution maps over small patches of the sky. This will provide much better lensing reconstruction, but also presents data analysis challenges. This thesis begins with an introduction to the field of CMB lensing and CMB lensing reconstruction. The second chapter details the biases present in reconstructing the lensing potential from CMB polarization maps considering first the full sky, and then small patches of sky. It also shows that using the pure-B mode formalism for the CMB polarization leads to improved lensing reconstruction over the naive case on the cut sky. Given the upcoming improvement in the CMB lensing reconstruction, it is expected that cross-correlations of the CMB lensing with other structure tracers, such as galaxies, will yield improved information for cosmology. It is also expected that the CMB lensing will become useful to help constrain uncertainties in the galaxy power spectrum, and provide information on the linear galaxy bias and redshift distribution. The third chapter of the thesis forecasts the power of cross correlation science for a number of galactic and non-galactic parameters. Finally, the CMB lensing effects the level of non-Gaussianity observed in the CMB. The fourth chapter of the thesis is a study of the lensing effect on the primordial squeezed bispectrum. We conclude in the fifth chapter.
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Lin, Tsu-Shiuan. "Accelerating radio transient detection using the Bispectrum algorithm and GPGPU." Master's thesis, University of Cape Town, 2015. http://hdl.handle.net/11427/21198.
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Modern radio interferometers such as those in the Square Kilometre Array (SKA) project are powerful tools to discover completely new classes of astronomical phenomena. Amongst these phenomena are radio transients. Transients are bursts of electromagnetic radiation and is an exciting area of research as localizing pulsars (transient emitters) allow physicists to test and formulate theories on strong gravitational forces. Current methods for detecting transients requires an image of the sky to be produced at every time step. Since interferometers have more information available to them, the computational demands for producing images becomes infeasible due to the larger data sets provided by larger interferometers. Law and Bower (2012) formulated a different approach by using a closure quantity known as the "bispectrum": the product of visibilities around a closed loop of antennae. The proposed algorithm has been shown to be easily parallelized and suitable for Graphics processing units (GPUs).Recent advancements in the field of many core technology such as GPUs has demonstrated significant performance enhancements to many scientific applications. A GPU implementation of the bispectrum algorithm has yet to be explored. In this thesis, we present a number of modified implementations of the bispectrum algorithm, allowing both instruction-level and data-level parallelism. Firstly, a multi-threaded CPU version is developed in C++ using OpenMP and then compared to a GPU version developed using Compute Unified Device Architecture (CUDA).In order to verify validity of the implementations presented, the implementations were firstly run on simulated data created from MeqTrees: a tool for simulating transients developed by the SKA. Thereafter, data from the Karl Jansky Very Large Array (JVLA) containing the B0355+54pulsar was used to test the implementation on real data. This research concludes that the bispectrum algorithm is well suited for both CPU and GPU implementations as we achieved a 3.2x speed up on a 4-core multi-threaded CPU implementation over a single thread implementation. The GPU implementation on a GTX670, achieved about a 20 times speed-up over the multi-threaded CPU implementation. These results show that the bispectrum algorithm will open doors to a series of efficient transient surveys suitable for modern data-intensive radio interferometers.
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Lazanu, Andrei. "The power spectrum and bispectrum of inflation and cosmic defects." Thesis, University of Cambridge, 2016. https://www.repository.cam.ac.uk/handle/1810/256999.
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Much of the recent progress in cosmology has come from studying the power spectrum of the cosmic microwave background (CMB). The latest results from the Planck satellite confirmed that the inflationary paradigm with the $\Lambda$CDM six-parameter model provides a very good description of the observed structures in the Universe. Even so, additional parameters, such as cosmic defects, are still allowed by current observational data. Additionally, many of the inflationary models predict a significant departure from Gaussianity in the distribution of primordial perturbations. Higher order statistics, such as the bispectrum, are required to test and constrain such models. The late-time distribution of matter in the Universe - large-scale structure (LSS) - contains much more information than the CMB that has not yet been used. In this thesis, we look at both problems: the effects of cosmic defects, in particular cosmic strings and domain walls on the CMB power spectrum through numerical simulations, and the dark matter bispectrum of large-scale structure. Topological defects are predicted by most inflationary theories involving symmetry breaking in the early Universe. In this thesis we study the effects of cosmic strings and domain walls on the CMB by determining their power spectrum. We use Nambu-Goto and field theory simulations for cosmic strings and domain walls respectively, and we determine the power spectra they produce with a modified Einstein-Boltzmann solver sourced by unequal time correlators from components of the energy-momentum tensor of the defects. We use these spectra together with CMB likelihoods to obtain constraints on the energy scales of formation of the cosmic defects, finding $G\mu/c^{2} < 1.29 \times 10^{−7}$ and $\eta < 0.93$ MeV (at 95% confidence level) for cosmic strings and domain walls respectively, when using the Planck satellite likelihoods. For the matter bispectrum of LSS, we compare different perturbative and phenomenological models with measurements from $N$-body simulations by using shape and amplitude correlators and we determine on which scales and for which redshifts they are accurate. We propose a phenomenological ‘three-shape’ model, based on the fundamental shapes we have observed by studying the halo model that are also present in the simulations. When calibrated on the simulations, this model accurately describes the bispectrum on all scales and redshifts considered, providing a prototype bispectrum HALOFIT-like methodology that could be used to describe and test parameter dependencies.
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Durand, Pierre. "Théorie et estimation conventionnelle du bispectre : application aux processus linéaires-quadratiques à spectre de raies." Grenoble INPG, 1991. http://www.theses.fr/1991INPG0063.
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Cette these est consacree a la construction et a la caracterisation de nouveaux outils de traitement du signal utilisant les statistiques d'ordre superieur. La notion de cumulants de variables aleatoires est tout d'abord introduite. Elle intervient ensuite dans les definitions des multicorrelations et des multispectres d'un processus reel, dont on expose les proprietes generales. Le multispectre d'ordre trois, ou bispectre, est ensuite etudie en detail. Ses proprietes vis-a-vis des bruits blancs, des processus lineaires et des processus lineaires-quadratiques, apportent une solution a des problemes jusqu'alors insolubles en utilisant uniquement l'information de l'ordre deux. Une normalisation du bispectre, la bicoherence, mesure la gaussianite et la linearite du processus. Sont etudies des estimateurs du bispectre de type fourier. Une synthese de leurs proprietes statistiques est proposee. Les problemes numeriques de l'estimation du bispectre et de la bicoherence sont presentes. Pour un processus a spectre de raies, la bicoherence detecte un couplage quadratique entre trois composantes frequentielles. Cette propriete est utilisee pour developper une methode de detection de la variation du modele lineaire-quadratique. Appliquee a des enregistrements espaces dans le temps des vibrations d'un systeme d'engrenages, cette methode chiffre l'etat d'usure et peut donc etre utilisee pour predire une rupture. Enfin, le bispectre resoud le probleme d'identification aveugle d'un systeme lineaire lorsque la densite de probabilite du bruit blanc d'entree est non symetrique. La deconvolution aveugle de donnees sismiques en utilisant le bispectre est comparee aux resultats classiques
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Mohamed-Benkadda, Mohamed Sadruddin. "Turbulence fluide étude optique et analyse bispectrale des couplages de modes /." Grenoble 2 : ANRT, 1987. http://catalogue.bnf.fr/ark:/12148/cb376080516.
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Wear, Steven M. "Shift-invariant image reconstruction of speckle-degraded images using bispectrum estimation /." Online version of thesis, 1990. http://hdl.handle.net/1850/11219.
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Duboisset-Chareyre, Laure. "Analyse bispectrale de signaux réels : application à la détection de transitoires." Grenoble INPG, 1997. http://www.theses.fr/1997INPG0168.
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En lutte sous-marine, des l'acquisition d'un signal en sortie d'une antenne sonar, la premiere question qui se pose est : <<<>le signal comporte-t-il de l'information ou ne s'agit-il que de bruit?<>>> cette question est determinante pour la securite de l'equipage et du batiment. Depuis peu, on s'interesse a la detection des bruits transitoires. Signaux brefs, emis lors de manoeuvres, ils sont souvent moins discrets que les bruits rayonnes classiques mais leur caractere fugitif les avait rendus jusque-la moins remarquables. Les methodes classiques de detection sont souvent mal adaptees a ce type de signaux. C'est pourquoi nous abordons d'autres methodes pour ameliorer cette detection. Des algorithmes utilisant les transformees temps-frequence et les ordres superieurs sont compares. A l'issue de cette etude, nous montrons l'interet d'une methode utilisant le calcul du bispectre. Ce dernier presente des caracteristiques remarquables que nous decrivons precisement. L'utilisation du detecteur bispectral nous amene a etudier en detail l'environnement reel dans lequel nous travaillons. Nous montrons notamment que le bruit de mer presente des caracteristiques proches de celles d'une gaussienne qui le differencie des transitoires a detecter. Enfin, notre souci etant de proposer un detecteur operationnel, nous avons mis au point la detection bispectrale en temps reel. Cela nous a amenes a faire des choix quant a la programmation du detecteur en terme, par exemple, de longueur de fenetres d'analyse lors de l'estimation du bispectre. Nous expliquons les difficultes rencontrees lors de l'implantation. Nous montrons comment elles ont ete resolues et presentons les performances de la methode et du programme.
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Mohamed-Benkadda, Mohamed Sadruddin. "Turbulence fluide : étude optique et analyse bispectrale des couplages de modes." Paris 11, 1987. http://www.theses.fr/1987PA112152.
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Méthode basée sur la diffusion de Rayleigh. Détermination des lois d'échelle et étude du mélange turbulent de deux gaz différents. Analyse bispectrale des signaux de diffusion. Estimation analytique du coefficient de couplage, basée sur une hypothèse de clôture du type R. P. A.
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Abolmoali, Philip. "Spectral Energy Transfers in Transonic Cavity Flows with High Frequency Flow Control from Powered Resonance Tubes." University of Cincinnati / OhioLINK, 2017. http://rave.ohiolink.edu/etdc/view?acc_num=ucin1511867795447293.
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Freeman, Jonathan Dennis. "Estimation of astronomical images from the bispectrum of atmospherically distorted infrared data." Diss., The University of Arizona, 1989. http://hdl.handle.net/10150/184939.
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The uses of the bispectrum for recovering the images of one-dimensional infrared astronomical speckle data are examined in detail. An analytic model for the bispectral transfer function, the variance, and the covariance of the bispectrum are developed. The models are evaluated by Monte Carlo integration and the results are compared to sample estimates of the same quantities obtained from simulated data. For comparison, the same sample quantities are computed from observed data. The bispectrum is shown to be useful for determining estimates of the object phase. A recursive method which is used to obtain the object phase estimates is introduced. Since the bispectrum provides multiple estimates of each object phase, a number of methods for combining the multiple estimates are developed and compared. Many techniques have been proposed to determine the phase of images which have been atmospherically distorted. Among these techniques are the Knox-Thompson, and the Simple Shift-and-Add algorithms. These methods are compared to the bispectrum via an objective measure which is developed. Optimization techniques are used to great success. A model for the bispectrum of a binary star is developed and fit to the image bispectrum by the Levenberg-Marquardt algorithm for non-linear least squares. The ability of the algorithm to determine binary star parameters from the bispectrum is tested with both simulated and observed data. Since the bispectrum may not always be available, a method is developed which determines binary star parameters from the image Fourier transform. The full set of object phases and moduli are determined by use of the conjugate gradient and conjugate direction algorithms in the last section. Two starting points for each algorithm are employed. The first starting point uses the estimates of the object phases obtained from the recursive bispectrum technique. The second assumes no information is known about the object. The speed of convergence of each algorithm is analyzed and recommendations are made for future use.
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Clunan, Timothy Peter. "The primordial universe : instantons, the ghost spectrum and the closed universe bispectrum." Thesis, University of Cambridge, 2010. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.608826.
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Liu, Ngai. "Asservissement des agents d'anesthésie intraveineux par l'activité électro-corticale." Versailles-St Quentin en Yvelines, 2008. http://www.theses.fr/2008VERS0025.
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L’anesthésie générale se définit comme un état réversible induit par des agents d’anesthésie agissant sur la conscience pour les hypnotiques, l’analgésie pour le morphinomimétiques et le relâchement musculaire pour les curares. L’effet de l’hypnotique est mesurable directement par l’activité électro-corticale. Une stimulation nociceptive provoque une activation électro-corticale lorsque l’analgésie est insuffisante. Nous disposons de différents moniteurs qui quantifient l’activité électro-corticale par une analyse bispectrale (BIS) ou du désordre (Entropy) de l’électro-encéphalogramme. L’ objectif de ce projet est la mise au point d’une double boucle fermée entre un hypnotique intraveineux (propofol) et un morphinomimétique intraveineux (rémifentanil) asservis à l’activité électro-corticale lors de l’anesthésie générale. La boucle fermée permet d’ajuster les quantités de médicament afin d’obtenir l’effet souhaité tout en limitant les effets secondaires. Les différentes étapes de ce projet ont consisté à déterminer l’interaction des curares lors de l’induction de l’anesthésie sur le BIS. Mise au point et validation clinique d’un algorithme permettant l’asservissement du propofol au BIS lors de l’induction. Mise au point et validation clinique d’un algorithme permettant l’asservissement du propofol au BIS lors de l’induction et de l’entretien de l’anesthésie. Validation clinique de cette boucle fermée lors de situation extrême. Mise au point et validation clinique d’une double boucle propofol-rémifentanil avec comme seul signal entrant le BIS. Création d’une base de donnée avec enregistrement simultanée du BIS et de l’Entropy. Mise au point d’une double boucle fermée guidée par l’Entropy. Au total, nos travaux démontrent l’activité électro-corticale seul permet l’asservissement simultané d’un hypnotique et d’un morphinomimétiqueGeneral anesthesia can be defined as a reversible pharmacological state related to effect on consciousness for hypnotic agent, analgesia for opioid agent and muscle relaxation for neuromuscular blocking agent. Hypnotic effect is measured directly by the electro-cortical activity. Moreover, a noxious stimuli may cause cortical activation when the antinociception level is insufficient. We have different monitors which measure the electro-cortical activity by bispectrale (BIS) or entropy analysis (Entropy) of electroencephalographic raw. The aim of this project was to develop a dual closed-loop controller for an intravenous hypnotic agent (propofol) and an intravenous opioid agent (remifentanil) guided by the electro-cortical activity. The closed-loop controller allows to adjust the drug flow to the minimum necessary for the effectiveness and reducing thereby side effects. The different steps of this project were to determine the interaction of neuromuscular blocking agent during the induction of anesthesia on the electro-cortical activity. Development and clinical validation of an algorithm allowing the feedback control of propofol guided by the BIS during the induction. Development and clinical algorithm validation allowing the feedback control of propofol during anesthesia induction and maintenance. Clinical Validation of the controller during extreme condition. Development and clinical validation of a dual-loop controller steering remifentanil and propofol guided by the BIS as single input. Development of patients database with simultaneous recording of BIS and the Entropy and clinical validation of a dual closed-loop controller guided by the Entropy. Finally, we have demonstrated that the electro-cortical activity solely can steer automatically a hypnotic and opioid agents
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Santos, Gustavo José von Glehn [UNESP]. "Avaliação paramétrica das associações anestésicas atropina-xilazinacetamina, levomepromazina-zomidazolam-cetamina em cães: aspectos nociceptivos e índice bispectral." Universidade Estadual Paulista (UNESP), 2003. http://hdl.handle.net/11449/89126.
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santos_gjg_me_botfmvz.pdf: 1424431 bytes, checksum: f89df8af775fecc755d6047f8022753f (MD5)Avaliou-se o comportamento bispectral e multiparamétrico de cães anestesiados com atropina-xilazina-cetamina, levomepromazina-tiletamina-zolazepam e levomepromazina-cetamina-midazolam. Para tanto foram empregados 30 cães machos ou fêmeas sadios e não prenhes. A monitoração foi realizada em momentos: distribuídos em: M0, imediatamente antes a administração da medicação pré-anestésica; M1, 15 minutos após a administração da medicação pré-anestésica e imediatamente anterior a administração da associação anestésica; e M2 e M7, que referem-se às aferições realizadas em intervalos de 10 minutos iniciados após a administração da associação anestésica. A partir dos resultados observados pode-se concluir que: os fármacos dissociativos apresentam pouca influencia sobre a redução do índice bispectral, sendo a redução mais marcante, verificada no grupo tratado com levomepromazina-tiletamina-zolazepam. O índice bispectral apresentou variações em função da estimulação do paciente no período trans anestésico. Os fármacos dissociativos mostraram-se ineficientes na abolição de dor visceral, apresentando efeito fugaz na analgesia somática, sendo estes acompanhados de recuperação desconfortável e elevados índices de avaliação bispectral.
The bispectral and multiparametric behaviour was studied in 30 healthy and non pregnant mongrel dogs submitted to atropine-xilazine-ketamine, levomepromazine-tiletamine-zolazepam and levomepromazine-ketamine-midazolam. The monitoring were done in moments M0, immediately before the pre-anesthetic medication; M1, immediately after the pre-anesthetic medication and before the anesthetic association; and M2 to M7 in each 10 minutes intervals. The results showed the low influence of the dissociative medications on the bispectral index reduce, and decrease was specially observed in the group treated with levomepromazine-tiletamine-zolazepam. the bispectral index. Variations in bispectral index was influenciated by the animal manipulation during the trans-anesthetic period. The dissociative drugs indicated inefficient effects in the abolition visceral pain, showing shorts duration effects in abolition if the somatic pain accomplished by high levels of bispectral measurement.
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Santos, Gustavo José von Glehn. "Avaliação paramétrica das associações anestésicas atropina-xilazinacetamina, levomepromazina-zomidazolam-cetamina em cães : aspectos nociceptivos e índice bispectral /." Botucatu : [s.n.], 2003. http://hdl.handle.net/11449/89126.
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Orientador : Flávio MassoneResumo: Avaliou-se o comportamento bispectral e multiparamétrico de cães anestesiados com atropina-xilazina-cetamina, levomepromazina-tiletamina-zolazepam e levomepromazina-cetamina-midazolam. Para tanto foram empregados 30 cães machos ou fêmeas sadios e não prenhes. A monitoração foi realizada em momentos: distribuídos em: M0, imediatamente antes a administração da medicação pré-anestésica; M1, 15 minutos após a administração da medicação pré-anestésica e imediatamente anterior a administração da associação anestésica; e M2 e M7, que referem-se às aferições realizadas em intervalos de 10 minutos iniciados após a administração da associação anestésica. A partir dos resultados observados pode-se concluir que: os fármacos dissociativos apresentam pouca influencia sobre a redução do índice bispectral, sendo a redução mais marcante, verificada no grupo tratado com levomepromazina-tiletamina-zolazepam. O índice bispectral apresentou variações em função da estimulação do paciente no período trans anestésico. Os fármacos dissociativos mostraram-se ineficientes na abolição de dor visceral, apresentando efeito fugaz na analgesia somática, sendo estes acompanhados de recuperação desconfortável e elevados índices de avaliação bispectral.
Abstract: The bispectral and multiparametric behaviour was studied in 30 healthy and non pregnant mongrel dogs submitted to atropine-xilazine-ketamine, levomepromazine-tiletamine-zolazepam and levomepromazine-ketamine-midazolam. The monitoring were done in moments M0, immediately before the pre-anesthetic medication; M1, immediately after the pre-anesthetic medication and before the anesthetic association; and M2 to M7 in each 10 minutes intervals. The results showed the low influence of the dissociative medications on the bispectral index reduce, and decrease was specially observed in the group treated with levomepromazine-tiletamine-zolazepam. the bispectral index. Variations in bispectral index was influenciated by the animal manipulation during the trans-anesthetic period. The dissociative drugs indicated inefficient effects in the abolition visceral pain, showing shorts duration effects in abolition if the somatic pain accomplished by high levels of bispectral measurement.
Mestre
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Ammermann, Peter A. "Nonlinearity and Overseas Capital Markets: Evidence from the Taiwan Stock Exchange." Diss., Virginia Tech, 1999. http://hdl.handle.net/10919/28816.
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Numerous studies have documented the existence of nonlinearity within various financial time series. But how important of a finding is this? This dissertation examines this issue from a number of perspectives. First, is the nonlinearity that has been found a statistical anomaly that is isolated to a few of the more widely known financial time series or is nonlinearity a statistical regularity inherent in such series? Second, even if nonlinearity is pervasive, does this finding have any practical relevance for finance practitioners or academics?
Using the relatively financially isolated but nonetheless well-traded Taiwan Stock Exchange as a case study, it is found that virtually all of the stocks trading on this exchange exhibit nonlinearity. The pervasiveness of nonlinearity within this market, combined with earlier results from other markets, suggests that nonlinearity is an inherent aspect of financial time series. Furthermore, closer examination of the time-paths of various measures of this nonlinearity via both windowed testing and recursive testing and parameter estimation reveals an additional complication, the possibility of nonstationarity. The serial dependency structures, especially for the nonlinear dependencies, do not appear to be constant, but instead appear to exhibit a number of brief episodes of extremely strong dependencies, followed by longer stretches of relatively quiet behavior. On average, though, these nonlinearities appear with sufficient strength to be significant for the full sample.
Continuing on to examine the relevance of such nonlinearities for empirical work in finance, a variety of conditionally heteroskedastic models were fit to the returns for a subsample Taiwanese stocks, the Taiwanese stock index, and stock indices for other stock markets, including New York, London, Tokyo, Hong Kong, and Singapore. In a majority of cases, such models appear to be successful at filtering out the extant nonlinearity from these series of returns; however, a variety of indicators suggest that these models are not statistically well-specified for these returns, calling into question the inferences obtained from these models. Furthermore, a comparison of the various conditionally heteroskedastic models with each other and with a dynamic linear regression model reveals that, for many of the data series, the inferences obtained from these models regarding the day-of-the-week effect and the extant autocorrelation within the data varied from model to model. This finding suggests the importance of adequately accounting for nonlinear serial dependencies (and of ensuring data stationarity) when studying financial time series, even when other empirical aspects of the data are the focus of attention.Ph. D.
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Belmonte, Emilio de Almeida [UNESP]. "Infusão contínua de morfina ou fentanil, associados à licodaína e cetamina, em cães anestesiados com isofluorano." Universidade Estadual Paulista (UNESP), 2008. http://hdl.handle.net/11449/89051.
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belmonte_ea_me_jabo.pdf: 395445 bytes, checksum: 92da23e7783cda1b9d0618c6cb55f316 (MD5)Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES)
Objetivou-se avaliar os parâmetros cardiovasculares e respiratórios, em cães anestesiados com isofluorano, submetidos à infusão contínua de morfina (3,3 μg/Kg/min) ou fentanil (0,03 μg/Kg/min), associados à lidocaína (50 μg/Kg/min) e cetamina (10 μg/Kg/min). Para tal, formaram-se dois grupos de oito animais, denominados morfina-lidocaína-cetamina MLK e fentanil-lidocaína-cetamina (FLK). Os cães foram pré-tratados com levomepromazina (0,5 mg/Kg IV), induzidos à anestesia com propofol (5 mg/Kg) e mantidos com isofluorano, ajustando-se a concentração para obterem-se valores de índice biespectral (BIS) entre 55 e 65. As mensurações da freqüência cardíaca (FC), duração (Ps) e amplitude (PmV) da onda P, intervalo PR, duração do complexo QRS, intervalo QT e RR, pressões arteriais sistólica (PAS), diastólica (PAD), e média (PAM), concentração de isofluorano expirado (EtISO), tensão de dióxido de carbono expirado (EtCO2), saturação de oxihemoglobina (SpO2) freqüência respiratória (f), tempo para extubação (Te), temperatura esofágica (T) e consumo de anestésico (ISOmL) tiveram início 30 minutos após a indução (M0), e após o início da infusão das soluções, em intervalos de 15 minutos (M15 a M75). Os dados foram submetidos à análise de perfil (P < 0,05) e ao Teste T (P < 0,05). À exceção da T (grupo FLK), não houve diferenças entre momentos para as demais variáveis. Entre grupos, EtISO (M30), FC (M0, M45, M60 e M75) e QRS (M60), ISOmL e T (M30, M45, M60 e M75), apresentaram médias do grupo MLK maiores que as do FLK. Para QT (M30 e M75), RR (M0, M60 e M75) e SpO2 (M60), as médias do grupo MLK foram menores que as do FLK. Concluiu-se que as soluções testadas não comprometem os parâmetros avaliados e não prejudicam a monitoração da profundidade anestésica por meio do BIS.
The aim of this study was investigate the effects over cardiovascular and respiratory system related with the continuous rate infusion of morphine (3,3mg/Kg/min) or fentanyl (0,03mg/Kg/min) associated with a solution of lidocaine (50ug/Kg/min) and ketamine (10ug/Kg/min). For such, two groups named morphine-lidocaine-ketamine (MLK) and fentanyl-lidocaine-ketamine (FLK) with eight dogs each were formed. As preanesthetic medication, the dogs received levomepromazine (0,5mg/Kg – IV). For induction and maintenance of anesthesia, propofol (5mg/Kg –IV) and isoflurane were used respectively. The values of bispectral index (BIS) were maintained between 55 and 65. The measurements of heart rate (HR), length (Ps) and amplitude (PmV) of the P wave, PR interval, duration of the QRS complex, QT interval and RR, systolic blood pressures (SBP), diastolic (DBP) and mean (MAP), expired concentration of isoflurane (EtISO), tension of carbon dioxide expired (ETCO2), oxyhemoglobin saturation (SpO2) respiratory rate (f), time to extubation (Te), esophageal temperature (T) and consumption of anesthetics (ISOmL) started 30 minutes after induction (M0), and after the infusion of solutions, at intervals of 15 minutes (M15 to M75). The data were submitted to analysis of profile (P <0.05) and the T test (P <0.05). With the exception of T (FLK group), there was no difference between moments for the other variables. Among groups, EtISO (M30), FC (M0, M45, M60 and M75) and QRS (M60), ISOmL and T (M30, M45, M60 and M75), showed means of MLK more than FLK. For QT (M30 and M75), RR (M0, M60 and M75) and SpO2 (M60), the means of MLK were smaller than FLK. The result of this study demonstrates that booth tested solutions not alters the respiratory or cardiovascular parameters, but, the solution with fentanyl promotes temperature reduction.
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Pidde, Aleksandra. "Dynamics of the membrane potential: studies of the membrane potential of Jurkat cells using wavelet and wavelet bispectral analysis." Doctoral thesis, Universitat Pompeu Fabra, 2020. http://hdl.handle.net/10803/670401.
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Fluctuations are fundamental for living organisms. They arguably result from interactions with the complex, and unpredictable environment, and can often be manifested as temporal variability. The cell must continually resist the external variations in the osmotic pressure by continuous adjustments in the intracellular concentrations. This happens through a highly specialised network of membrane transporters, and is manifested in the dynamics of the membrane potential. The aim of the work presented here is to provide understanding and insight into the dynamics of the free-running membrane potential in nonexcitable cells, based on experimental data. In order to achieve this, first the quantitative comparisons of the average values of the membrane potential and their standard deviations recorded in various conditions are made. The analysis is further extended through the use of the wavelet transform to investigate the time and frequency components of the signal. This work is the first to report an intermittent oscillations in the membrane potential around frequency of 8 mHz but also around frequencies of 0.03, 0.05 or 0.09 Hz. To further understand this dynamics from univariate time series, time-reversibility is investigated and a novel wavelet-bispectral density analysis is developed. The wavelet-bispectral density allows for a formal quantitative, not merely qualitative interpretation of the results of wavelet-bispectral analysis. Finally, the newly developed autowavelet-bispectral analysis is applied to the recordings of the membrane potential. These indicate possible nonlinear couplings between different oscillatory modes in the cellular membrane potential.Les fluctuacions són fonamentals pels éssers vius i probablement siguin el resultat d’interaccions amb un entorn complex i impredictible. Aquest tipus d’activitat es pot manifestar en forma de variabilitat temporal. Les cèl.lules han de resistir contínuament les variacions externes de la pressió osmòtica fent reajustaments continus de les concentracions intracel.lulars. Això és possible gràcies a una xarxa altament especialitzada de transportadors de membrana i dóna lloc a la dinàmica del potencial de membrana. L’objectiu d’aquest treball és proporcionar una millor comprensió de la dinàmica del potencial lliure de membrana en cèl.lules no excitables a partir de dades experimentals. Amb aquest objectiu i en primer lloc, comparem la mitjana i la desviació estàndard del potencial de membrana en diferents condicions de registre. Complementem aquesta anàlisi investigant les components temporo-freqüencials de la senyal mitjançant la transformada wavelet. Aquest és el primer treball on es reporten oscil.lacions intermitents del potencial de membrana amb una freqüència aproximada de 8 mHz, però també al voltant de 0.03, 0.05 i 0.09 Hz. Per entendre millor aquest comportament en el context d’una sèrie temporal univariada, utilitzem el biespectre-wavelet i l’anàlisi de reversibilitat del temps. A més, proposem una nova mesura, la densitat biespectral-wavelet, que permet fer una interpretació quantitativa -i no només qualitativa- dels resultats de l’ànalisi biespectralwavelet. L’aplicació del nou formalisme als registres del potencial de membrana posa de manifest l’existència de possibles acoblaments no lineals entre diferents modes oscil.latoris en el potencial de membrana.
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Dusi, Gabriel Aikawa. "Interferência da hipoxemia na avaliação do nível de consciência pelo índice bispectral em cavalos anestesiados com propofol ou isofluorano." reponame:Repositório Institucional da UFPR, 2017. http://hdl.handle.net/1884/48527.
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Orientador : Prof. Dr. Ricardo Guilherme D'Otaviano de Castro VilaniDissertação (mestrado) - Universidade Federal do Paraná, Setor de Ciências Agrárias, Programa de Pós-Graduação em Ciências Veterinárias. Defesa: Curitiba, 28/03/2017
Inclui referências : f. 50-55
Área de concentração : Ciências Veterinárias
Resumo: O índice bispectral (BIS) é um parâmetro derivado do eletroencefalograma que permite a monitoração da profundidade anestésica de forma quantitativa. Embora sua utilização seja ampla na medicina, seu uso é limitado na medicina veterinária, havendo diferentes resultados quanto a sua aplicabilidade, inclusive em cavalos. A hipoxemia não é uma complicação incomum na anestesia equina, podendo levar a alterações do BIS de forma que este não reflita corretamente o componente hipnótico da anestesia. Este estudo teve como objetivos comparar o índice bispectral e a avaliação clínica da profundidade anestésica em cavalos anestesiados com isofluorano ou propofol e avaliar a influência da hipoxemia nos valores do BIS em cavalos submetidos a hipoxemia por ventilação monopulmonar. Foram utilizados seis animais submetidos a anestesia para toracoscopia. Após pré-medicação com xilazina e indução anestésica com propofol e guaiafenesina, a anestesia foi mantida com propofol (PRO) ou isofluorano (ISO) sendo a taxa de infusão e a fração expirada dos anestésicos alteradas segundo avaliação clínica da profundidade anestésica. O BIS foi avaliado nos animais acordados, após 10 minutos de sedação, a cada 10 minutos durante a manutenção da anestesia, no início do despertar e no momento da extubação. Foram avaliados parâmetros cardiovasculares e respiratórios, variáveis hemodinâmicas e de oxigenação tecidual durante a anestesia. Os valores médios de BIS foram 97±1 para animais acordados e 80±6 para animais sedados, havendo diferença significativa entre estes e entre os animais anestesiados (p<0,05). Para os planos superficial, adequado e profundo de anestesia o BIS foi 68±1, 67±10 e 59±7, respectivamente, sendo o BIS no plano profundo significativamente menor quando comparado ao plano superficial (p=0,014) No inicio do despertar o BIS foi de 79±8 e de 87±6 no momento da extubação, valor significativamente mais alto quando comparado aos animais anestesiados. A hipoxemia levou a aumento significativo nos valores de BIS de 59±6 para 65±7 (p=0,012), acompanhado de aumento na FC, PAM e EMG no PRO. O BIS pode ser utilizado para diferenciar planos mais profundos de anestesia em cavalos, em especial quando anestesiados com isofluorano, e na percepção do despertar em cavalos anestesiados com propofol ou isofluorano. A hipoxemia ocasionar o aumento nos valores de BIS decorrente da ativação simpática e aumento da EMG em cavalos anestesiados com propofol. Palavras-chave: eletroencefalograma; equinos; oxigenação; TIVA
Abstract: Bispectral index (BIS) is an electroencephalogram derivated parameter which allows depth of anesthesia monitoring in an objective way. Althought it has a widespread use in medicine, its use in veterinary medicine is limitated, with different results regarding its applicability, including horses. Hypoxemia is not an uncommon complication during equine anesthesia and may lead to BIS changes so that it does not accurately reflect the hypnotic component of anesthesia. The objectives of this study were to compare the bispectral index and clinical evaluation of anesthetic depth in horses anesthetized with isoflurane or propofol; and to evaluate the influence of hypoxemia on BIS values in horses submitted to hypoxemia by monopulmonary ventilation. It were used six horses undergoing anesthesia for thoracoscopy. After premedication with xylazine and anesthetic induction with propofol and guaiafenesin, anesthesia was maintained with propofol (PRO) or isoflurane (ISO) and the infusion rate and the expired fraction of the anesthetics were altered according to clinical evaluation of anesthetic depth. The BIS was evaluated in the awake animals, 10 minutes after sedation, every 10 minutes during anesthesia maintenance, at the beginning of the awakening and at the time of extubation. Cardiovascular and respiratory parameters, hemodynamic variables and tissue oxygenation were evaluated during anesthesia. The mean values of BIS were 97 ± 1 for awake animals and 80 ± 6 for sedated animals, with a significant difference between these and between anesthetized animals (p <0.05). For the superficial, adequate and deep planes of anesthesia the BIS was 68 ± 1, 67 ± 10 and 59 ± 7, respectively, and the BIS in the deep plane was significantly smaller when compared to the superficial plane (p= 0.014). BIS was 79 ± 8 and 87 ± 6 at the time of extubation, a significantly higher value when compared to anesthetized animals. Hypoxemia led to a significant increase in BIS values from 59 ± 6 to 65 ± 7 (p = 0.012), accompanied by an increase in HR, MAP and EMG in the PRO. BIS can be used to differentiate deeper planes of anesthesia in horses, especially when anesthetized with isoflurane, and in the perception of awakening in horses anesthetized with propofol or isoflurane. Hypoxemia may lead to increased BIS values due to sympathetic activation and increased EMG in horses anesthetized with propofol. Key-Words: electroencephalogram; equine; oxygenation; TIVA
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Wang, Xue. "CARDIO-RESPIRATORY INTERACTION AND ITS CONTRIBUTION IN SYNCOPE." UKnowledge, 2006. http://uknowledge.uky.edu/gradschool_diss/254.
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A hypothetical causal link between ventilatory regulation of carbon dioxide anddevelopment of syncope during orthostatic challenges is reduction in arterial partialpressure of carbon dioxide and resultant reduction in cerebral blood flow. We performedtwo experiments to investigate the ventilatory sensitivity to carbon dioxide and factorsaffecting cerebral autoregulation (CA). We also studied the nonlinear phase couplingbetween cardio-respiratory parameters before syncope.For experiment one, in 30 healthy adults, we stimulated chemo and baro reflexesby breathing either room-air or room-air with 5 percent carbon dioxide in a pseudorandom binary sequence during supine and 70 degree head up tilt (HUT). Six subjectsdeveloped presyncope during tilt.To determine whether changes in ventilatory control contribute to the observeddecrease in PaCO2 during HUT, we assessed ventilatory dynamic sensitivity to changesin PaCO2 during supine and 70 degrees HUT. The sensitivity of the ventilatory controlsystem to perturbations in end tidal carbon dioxide increased during tilt.To investigate nonlinear phase coupling between cardio-respiratory parametersbefore syncope, bispectra were estimated and compared between presyncopal andnon-presyncopal subjects. Our results indicate that preceding presyncope, nonlinearphase coupling is altered by perturbations to baro and chemo reflexes.To investigate the effects of gender in CA, we selected 10 men and 10age-matched women and used spectral analysis to compare differences in CA betweenmen and women. Our results showed that gender-related differences in CA did exist andgender may need to be considered as a factor in investigating CA.To investigate the influence of induced hypocapnia on CA in absence ofventilatory variability, we performed experiment two in which subjects were randomlyassigned to a Control (under normocapnia) or Treatment (under hypocapnia) group. Bothgroups voluntarily controlled their breathing pattern yet two groups breathed in air withdifferent levels of carbon dioxide. Our results show that changes in mean blood pressureat middle cerebral artery level were less transferred into mean cerebral blood flow in theTreatment group than in the Control group, suggesting better CA under hypocapniarelative to under normocapnia.
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Lineburger, Eric Benedet [UNESP]. "Relação do índice bispetral e da taxa de supressão do traçado do eletroencefalograma com disfunção cognitiva pós-operatória em cirurgia de revascularização do miocárdio." Universidade Estadual Paulista (UNESP), 2014. http://hdl.handle.net/11449/113900.
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000795302.pdf: 290369 bytes, checksum: 58bda7f024f4cce4b41311ea8576a046 (MD5)Introdução: Não está claro na literatura se os valores do índice bispectral (BIS) e da taxa de supressão do traçado de eletroencefalograma (TS), estão relacionados à disfunção cognitiva pós-operatória (DCPO). Objetivo: Avaliar os valores de BIS e TS e sua relação com a DCPO após cirurgia de revascularização do miocárdio (CRM) em pacientes submetidos a anestesia com sevoflurano (SEVO) guiada pelo BIS. Tipo de estudo: Observacional prospectivo. Local do estudo: Hospital de ensino. Pacientes: Noventa pacientes adultos programados para CRM com ou sem circulação extra-corpórea (CEC). Intervenções: A anestesia foi induzida com propofol, remifentanil e atracúrio e mantida com concentrações expiradas de SEVO (ETSEVO) em valores de concentração alveolar mínima (CAMSEVO) adaptada à idade, tendo como alvo valores de BIS de 40-60. O Mini-Exame do Estado Mental (MEEM) para avaliação cognitiva dos pacientes foi aplicado na admissão hospitalar e três meses após a cirurgia. Variáveis estudadas: Os valores de BIS, TS, ETSEVO e CAMSEVO foram registrados a cada 5 minutos durante o procedimento. Redução de um desvio padrão (DP) ou mais no MEEM basal foi definida como DCPO. Resultados: A proporção de DCPO foi de 40%. Os pacientes foram alocados em dois grupos: com (n = 36) ou sem DCPO (n = 54). Não houve diferença significativa na incidência de DCPO entre os pacientes que foram submetidos à CRM com ou sem CEC (p = 1,0). Quanto às características dos pacientes, somente os valores de índice de massa corporal (IMC) foram maiores no grupo sem DCPO (p = 0,009). Valores médios de BSR, ETSEV e MACSEV foram maiores no grupo sem DCPO (p < 0,05). Em uma análise multivariada, valores menores de TS (Razão de Chances-RC 0,008, Intervalo de Confiança-IC 95% [0,001-0,53], p = 0,02), CAMSEVO (RC 0,001, IC 95% [0,001-0,08], p = 0,008), ETSEVO (RC 0,03, IC 95% [0,002-0,66], p = 0,02) e ...
Background: It is still controversial whether bispectral index (BIS) and burst suppression ratio (BSR) values are related to postoperative cognitive dysfunction (POCD). OBJECTIVE: To evaluate BIS and BSR values and their relation to POCD after coronary artery bypass grafting (CABG) surgery in patients undergoing BIS-guided sevoflurane (SEVO) anaesthesia. DESIGN: Prospective, observational study. SETTING: Teaching hospital. PATIENTS: Ninety adult patients scheduled for on- or off-pump CABG surgery. INTERVENTIONS: Anaesthesia was induced with propofol, remifentanil and atracurium and maintained with end-tidal SEVO (ETSEVO) at age-adapted minimum alveolar concentration (MACSEVO) targeting BIS values of 40-60. Mini-Mental State Examination (MMSE) for cognitive assessment of the patients was applied on hospital admission and at 3 months after surgery. MAIN OUTCOME MEASUREMENTS: BIS, BSR, ETSEVO and MACSEVO values were recorded every 5 minutes during the procedure. A decrease of 1 standard deviation or more from the basal MMSE was defined as POCD. RESULTS: The POCD proportion was 40%. The patients were allocated into two groups: with POCD (n=36) or no POCD (n=54). There was no difference of POCD incidence between patients who were submitted to on- versus off-pump CABG (P=1.0). With regard to the patient’s characteristics, only body mass index (BMI) was higher in the no-POCD group (P=0.009). Mean BSR, ETSEVO and MACSEVO values were higher in the no-POCD group (P<0.05). In a multivariable analysis, lower values of BSR (odds ratio-OR 0.008; 95%CI [0.001-0.53]; P=0.02), MACSEVO (OR 0.001; 95%CI [0.001-0.08]; P=0.008), ETSEVO (OR 0.03; 95%CI [0.002-0.66]; P=0.02) and BMI (OR 0.82; 95%CI [0.70-0.96]; P=0.01) were independent predictors of risk for POCD incidence. BIS values did not influence POCD incidence (OR 1.0; 95%CI [0.95-1.11]; P=0.40). CONCLUSION: BIS-guided SEVO anaesthesia titrated to a range between 40 and 60 is not a predictive factor ...
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Lineburger, Eric Benedet. "Relação do índice bispetral e da taxa de supressão do traçado do eletroencefalograma com disfunção cognitiva pós-operatória em cirurgia de revascularização do miocárdio /." Botucatu, 2014. http://hdl.handle.net/11449/113900.
Full textAbstract:
Orientador: José Reinaldo Cerqueira BrazBanca: Paulo do Nascimento Junior
Banca: Maria Angela Tardelli
Resumo: Introdução: Não está claro na literatura se os valores do índice bispectral (BIS) e da taxa de supressão do traçado de eletroencefalograma (TS), estão relacionados à disfunção cognitiva pós-operatória (DCPO). Objetivo: Avaliar os valores de BIS e TS e sua relação com a DCPO após cirurgia de revascularização do miocárdio (CRM) em pacientes submetidos a anestesia com sevoflurano (SEVO) guiada pelo BIS. Tipo de estudo: Observacional prospectivo. Local do estudo: Hospital de ensino. Pacientes: Noventa pacientes adultos programados para CRM com ou sem circulação extra-corpórea (CEC). Intervenções: A anestesia foi induzida com propofol, remifentanil e atracúrio e mantida com concentrações expiradas de SEVO (ETSEVO) em valores de concentração alveolar mínima (CAMSEVO) adaptada à idade, tendo como alvo valores de BIS de 40-60. O Mini-Exame do Estado Mental (MEEM) para avaliação cognitiva dos pacientes foi aplicado na admissão hospitalar e três meses após a cirurgia. Variáveis estudadas: Os valores de BIS, TS, ETSEVO e CAMSEVO foram registrados a cada 5 minutos durante o procedimento. Redução de um desvio padrão (DP) ou mais no MEEM basal foi definida como DCPO. Resultados: A proporção de DCPO foi de 40%. Os pacientes foram alocados em dois grupos: com (n = 36) ou sem DCPO (n = 54). Não houve diferença significativa na incidência de DCPO entre os pacientes que foram submetidos à CRM com ou sem CEC (p = 1,0). Quanto às características dos pacientes, somente os valores de índice de massa corporal (IMC) foram maiores no grupo sem DCPO (p = 0,009). Valores médios de BSR, ETSEV e MACSEV foram maiores no grupo sem DCPO (p < 0,05). Em uma análise multivariada, valores menores de TS (Razão de Chances-RC 0,008, Intervalo de Confiança-IC 95% [0,001-0,53], p = 0,02), CAMSEVO (RC 0,001, IC 95% [0,001-0,08], p = 0,008), ETSEVO (RC 0,03, IC 95% [0,002-0,66], p = 0,02) e ...
Abstract: BACKGROUND: It is still controversial whether bispectral index (BIS) and burst suppression ratio (BSR) values are related to postoperative cognitive dysfunction (POCD). OBJECTIVE: To evaluate BIS and BSR values and their relation to POCD after coronary artery bypass grafting (CABG) surgery in patients undergoing BIS-guided sevoflurane (SEVO) anaesthesia. DESIGN: Prospective, observational study. SETTING: Teaching hospital. PATIENTS: Ninety adult patients scheduled for on- or off-pump CABG surgery. INTERVENTIONS: Anaesthesia was induced with propofol, remifentanil and atracurium and maintained with end-tidal SEVO (ETSEVO) at age-adapted minimum alveolar concentration (MACSEVO) targeting BIS values of 40-60. Mini-Mental State Examination (MMSE) for cognitive assessment of the patients was applied on hospital admission and at 3 months after surgery. MAIN OUTCOME MEASUREMENTS: BIS, BSR, ETSEVO and MACSEVO values were recorded every 5 minutes during the procedure. A decrease of 1 standard deviation or more from the basal MMSE was defined as POCD. RESULTS: The POCD proportion was 40%. The patients were allocated into two groups: with POCD (n=36) or no POCD (n=54). There was no difference of POCD incidence between patients who were submitted to on- versus off-pump CABG (P=1.0). With regard to the patient's characteristics, only body mass index (BMI) was higher in the no-POCD group (P=0.009). Mean BSR, ETSEVO and MACSEVO values were higher in the no-POCD group (P<0.05). In a multivariable analysis, lower values of BSR (odds ratio-OR 0.008; 95%CI [0.001-0.53]; P=0.02), MACSEVO (OR 0.001; 95%CI [0.001-0.08]; P=0.008), ETSEVO (OR 0.03; 95%CI [0.002-0.66]; P=0.02) and BMI (OR 0.82; 95%CI [0.70-0.96]; P=0.01) were independent predictors of risk for POCD incidence. BIS values did not influence POCD incidence (OR 1.0; 95%CI [0.95-1.11]; P=0.40). CONCLUSION: BIS-guided SEVO anaesthesia titrated to a range between 40 and 60 is not a predictive factor ...
Mestre
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Thiesen, Roberto. "Efeitos da cetamina s(+) sobre parâmetros cardiorrespiratórios, hemogasométricos e índice biespectral, em cães anestesiados com sevofluorano /." Jaboticabal : [s.n.], 2010. http://hdl.handle.net/11449/101100.
Full textAbstract:
Orientador: Newton NunesBanca: Paulo Sérgio Patto dos Santos
Banca: Juan Carlos Duque Moreno
Banca: José Antonio Marques
Banca: Paola Castro Moraes
Resumo: Com este estudo, objetivou-se avaliar os efeitos da cetamina S(+) sobre parâmetros cardiorrespiratórios, hemogasométricos e índice biespectral (BIS), em cães induzidos à anestesia com sevofluorano por meio de máscara facial, intubados e mantidos anestesiados com o mesmo agente em concentração equivalente à 1 CAM, em circuito com reinalação parcial de gases, FiO2 = 0,6 e fluxo de 250mL + 30mL/kg em ventilação espontânea. Após 30 minutos da estabilização da anestesia e preparação dos animais, foram colhidos os valores basais. Subsequentemente os tratamentos foram realizados, sendo bolus de Ringer com Lactato para o grupo controle (GC) e cetamina S(+) (6mg/kg) para o grupo cetamina S(+) [GS(+)]. As variáveis foram registradas em intervalos de dez minutos após o tratamento durante a primeira hora e de 15 minutos na segunda hora. Os valores com distribuição normal foram submetidos à análise de variância (ANOVA) seguida pelo teste de Tukey. Os parâmetros que não passaram no teste de normalidade foram analisados pelo teste de Kruskal-Wallis. O nível de significância adotado para todos os testes foi de 5% (p<0,05). As variáveis hemogasométricas e cardiovasculares não sofreram alterações significativas durante todo o período anestésico. Observou-se diminuição nos valores de BIS imediatamente após o tratamento no GS(+). Neste grupo também ocorreu depressão respiratória após a aplicação do bolus, no entanto estes valores retornaram aos basais depois de 30 minutos. Concluiu-se que a associação de cetamina S(+) na dose de 6 mg/kg à anestesia com sevofluorano em cães, aprofundou o plano anestésico dos animais de maneira transitória, sem alterar significativamente seus parâmetros cardiovasculares e hemogasométricos
Abstract: The effects of (S)-ketamine on cardiorespiratory parameters, blood gases and bispectral index was evaluated in sixteen dogs anesthetized with sevoflurane (SEV). Animals received SEV by facemask until they had the laringotracheal reflex abolished and were able to be intubated. Dogs were kept under general anesthesia with SEV 1 MAC in closed circuit system, FiO2 = 0,6 and 250mL + 30mL/kg flow rate, breathing spontaneously. Baseline values were measured after 30 minutes to allow for the anesthetic concentration to achieve a steady-state. Subsequently, animals received a loading dose of (S)-ketamine (Cetamina S+ group) or Lactate's Ringer (Control group). Cardiorespiratory parameters, blood gases and bispectral index were measured in 10 minutes intervals during the first hour and each 15 minutes during the second hour of anesthesia. Between group and within group differences were evaluated using repeated measures ANOVA for parametric data. Tukey's test was applied when results were significant. For non-parametric data Kruskall-Wallis test was used. A P value < 0.05 was considered significant for all tests. There were no significant differences among treatments in cardiovascular parameters and blood gas analysis. Respiratory depression and decreased BIS values after (S)-ketamine injection were evidenced, however, the values returned to baseline after 30 minutes. It was concluded that the injection of an anesthetic dose of (S)-ketamine increased the depth of anesthesia transitorily without significant changes in cardiovascular and blood gas parameters
Doutor
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Hashimoto, Ichihiko. "Toward a precision cosmological test of gravity from redshift-space bispectrum based on perturbation theory." Kyoto University, 2018. http://hdl.handle.net/2433/232243.
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Olfe, Nils [Verfasser], and Boris A. [Akademischer Betreuer] Hoffmann. "Evaluation der Sedierungstiefe mittels "Bispectral Index Monitoring" bei Patienten während der Ablation von Herzrhythmusstörungen / Nils Olfe ; Betreuer: Boris A. Hoffmann." Hamburg : Staats- und Universitätsbibliothek Hamburg, 2019. http://d-nb.info/1186891939/34.
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Olfe, Nils Verfasser], and Boris A. [Akademischer Betreuer] [Hoffmann. "Evaluation der Sedierungstiefe mittels "Bispectral Index Monitoring" bei Patienten während der Ablation von Herzrhythmusstörungen / Nils Olfe ; Betreuer: Boris A. Hoffmann." Hamburg : Staats- und Universitätsbibliothek Hamburg, 2019. http://nbn-resolving.de/urn:nbn:de:gbv:18-97185.
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Yoo, Byungseok. "Practical Aspects of Assessing Nonlinear Ultrasonic Response of Cyclically Load 7075-T6 Aluminum." Thesis, Virginia Tech, 2006. http://hdl.handle.net/10919/36335.
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The ultrasonic NDE technique to characterize the ultrasonic nonlinear response of the cyclically load 7075-T6 aluminum is described in this thesis. In order to estimate the nonlinear relation of the ultrasonic waves due to material fatigue damage or degradation, the spectral analysis techniques such as the power spectrum, bispectrum, and bicoherence spectrum are applied. The ultrasonic nonlinearity parameters by Cantrell and Jhang are introduced and presented as a function of the material fatigue growth, the number of fatigue cycles. This thesis presents the effectiveness of the bispectral analysis for evaluating the nonlinear aspects of the ultrasonic wave propagation. The results show that the nonlinearity parameters by Cantrell and Jhang are responsive to the output amplitude of the received signal and vary for the various materials, and independent of the input frequency and the ultrasonic wave propagation distance. By using the bispectral analysis tools, particularly the bicoherence spectrum, the increase of the coupling levels between the fundamental, its harmonic, and subharmonic frequency components is presented as the number of fatigue cycles is increased. This thesis suggests that the application of the bicoherence spectrum based on the nonlinear wave coupling relations be more effective for estimating the level of the material fatigue life.Master of Science
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Thiesen, Roberto [UNESP]. "Efeitos da cetamina s(+) sobre parâmetros cardiorrespiratórios, hemogasométricos e índice biespectral, em cães anestesiados com sevofluorano." Universidade Estadual Paulista (UNESP), 2010. http://hdl.handle.net/11449/101100.
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Com este estudo, objetivou-se avaliar os efeitos da cetamina S(+) sobre parâmetros cardiorrespiratórios, hemogasométricos e índice biespectral (BIS), em cães induzidos à anestesia com sevofluorano por meio de máscara facial, intubados e mantidos anestesiados com o mesmo agente em concentração equivalente à 1 CAM, em circuito com reinalação parcial de gases, FiO2 = 0,6 e fluxo de 250mL + 30mL/kg em ventilação espontânea. Após 30 minutos da estabilização da anestesia e preparação dos animais, foram colhidos os valores basais. Subsequentemente os tratamentos foram realizados, sendo bolus de Ringer com Lactato para o grupo controle (GC) e cetamina S(+) (6mg/kg) para o grupo cetamina S(+) [GS(+)]. As variáveis foram registradas em intervalos de dez minutos após o tratamento durante a primeira hora e de 15 minutos na segunda hora. Os valores com distribuição normal foram submetidos à análise de variância (ANOVA) seguida pelo teste de Tukey. Os parâmetros que não passaram no teste de normalidade foram analisados pelo teste de Kruskal-Wallis. O nível de significância adotado para todos os testes foi de 5% (p<0,05). As variáveis hemogasométricas e cardiovasculares não sofreram alterações significativas durante todo o período anestésico. Observou-se diminuição nos valores de BIS imediatamente após o tratamento no GS(+). Neste grupo também ocorreu depressão respiratória após a aplicação do bolus, no entanto estes valores retornaram aos basais depois de 30 minutos. Concluiu-se que a associação de cetamina S(+) na dose de 6 mg/kg à anestesia com sevofluorano em cães, aprofundou o plano anestésico dos animais de maneira transitória, sem alterar significativamente seus parâmetros cardiovasculares e hemogasométricos
The effects of (S)-ketamine on cardiorespiratory parameters, blood gases and bispectral index was evaluated in sixteen dogs anesthetized with sevoflurane (SEV). Animals received SEV by facemask until they had the laringotracheal reflex abolished and were able to be intubated. Dogs were kept under general anesthesia with SEV 1 MAC in closed circuit system, FiO2 = 0,6 and 250mL + 30mL/kg flow rate, breathing spontaneously. Baseline values were measured after 30 minutes to allow for the anesthetic concentration to achieve a steady-state. Subsequently, animals received a loading dose of (S)-ketamine (Cetamina S+ group) or Lactate`s Ringer (Control group). Cardiorespiratory parameters, blood gases and bispectral index were measured in 10 minutes intervals during the first hour and each 15 minutes during the second hour of anesthesia. Between group and within group differences were evaluated using repeated measures ANOVA for parametric data. Tukey`s test was applied when results were significant. For non-parametric data Kruskall-Wallis test was used. A P value < 0.05 was considered significant for all tests. There were no significant differences among treatments in cardiovascular parameters and blood gas analysis. Respiratory depression and decreased BIS values after (S)-ketamine injection were evidenced, however, the values returned to baseline after 30 minutes. It was concluded that the injection of an anesthetic dose of (S)-ketamine increased the depth of anesthesia transitorily without significant changes in cardiovascular and blood gas parameters
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Belmonte, Emilio de Almeida. "Infusão contínua de morfina ou fentanil, associados à licodaína e cetamina, em cães anestesiados com isofluorano /." Jaboticabal : [s.n.], 2008. http://hdl.handle.net/11449/89051.
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Orientador: Newton NunesBanca: João Moreira da Costa Neto
Banca: Paulo Sérgio Patto dos Santos
Resumo: Objetivou-se avaliar os parâmetros cardiovasculares e respiratórios, em cães anestesiados com isofluorano, submetidos à infusão contínua de morfina (3,3 μg/Kg/min) ou fentanil (0,03 μg/Kg/min), associados à lidocaína (50 μg/Kg/min) e cetamina (10 μg/Kg/min). Para tal, formaram-se dois grupos de oito animais, denominados morfina-lidocaína-cetamina MLK e fentanil-lidocaína-cetamina (FLK). Os cães foram pré-tratados com levomepromazina (0,5 mg/Kg IV), induzidos à anestesia com propofol (5 mg/Kg) e mantidos com isofluorano, ajustando-se a concentração para obterem-se valores de índice biespectral (BIS) entre 55 e 65. As mensurações da freqüência cardíaca (FC), duração (Ps) e amplitude (PmV) da onda P, intervalo PR, duração do complexo QRS, intervalo QT e RR, pressões arteriais sistólica (PAS), diastólica (PAD), e média (PAM), concentração de isofluorano expirado (EtISO), tensão de dióxido de carbono expirado (EtCO2), saturação de oxihemoglobina (SpO2) freqüência respiratória (f), tempo para extubação (Te), temperatura esofágica (T) e consumo de anestésico (ISOmL) tiveram início 30 minutos após a indução (M0), e após o início da infusão das soluções, em intervalos de 15 minutos (M15 a M75). Os dados foram submetidos à análise de perfil (P < 0,05) e ao Teste T (P < 0,05). À exceção da T (grupo FLK), não houve diferenças entre momentos para as demais variáveis. Entre grupos, EtISO (M30), FC (M0, M45, M60 e M75) e QRS (M60), ISOmL e T (M30, M45, M60 e M75), apresentaram médias do grupo MLK maiores que as do FLK. Para QT (M30 e M75), RR (M0, M60 e M75) e SpO2 (M60), as médias do grupo MLK foram menores que as do FLK. Concluiu-se que as soluções testadas não comprometem os parâmetros avaliados e não prejudicam a monitoração da profundidade anestésica por meio do BIS.
Abstract: The aim of this study was investigate the effects over cardiovascular and respiratory system related with the continuous rate infusion of morphine (3,3mg/Kg/min) or fentanyl (0,03mg/Kg/min) associated with a solution of lidocaine (50ug/Kg/min) and ketamine (10ug/Kg/min). For such, two groups named morphine-lidocaine-ketamine (MLK) and fentanyl-lidocaine-ketamine (FLK) with eight dogs each were formed. As preanesthetic medication, the dogs received levomepromazine (0,5mg/Kg - IV). For induction and maintenance of anesthesia, propofol (5mg/Kg -IV) and isoflurane were used respectively. The values of bispectral index (BIS) were maintained between 55 and 65. The measurements of heart rate (HR), length (Ps) and amplitude (PmV) of the P wave, PR interval, duration of the QRS complex, QT interval and RR, systolic blood pressures (SBP), diastolic (DBP) and mean (MAP), expired concentration of isoflurane (EtISO), tension of carbon dioxide expired (ETCO2), oxyhemoglobin saturation (SpO2) respiratory rate (f), time to extubation (Te), esophageal temperature (T) and consumption of anesthetics (ISOmL) started 30 minutes after induction (M0), and after the infusion of solutions, at intervals of 15 minutes (M15 to M75). The data were submitted to analysis of profile (P <0.05) and the T test (P <0.05). With the exception of T (FLK group), there was no difference between moments for the other variables. Among groups, EtISO (M30), FC (M0, M45, M60 and M75) and QRS (M60), ISOmL and T (M30, M45, M60 and M75), showed means of MLK more than FLK. For QT (M30 and M75), RR (M0, M60 and M75) and SpO2 (M60), the means of MLK were smaller than FLK. The result of this study demonstrates that booth tested solutions not alters the respiratory or cardiovascular parameters, but, the solution with fentanyl promotes temperature reduction.
Mestre