Remifentanil bolus dose is a safe procedure to control intense noxious stimuli in hypertensive neurosurgical patients

Patients with hypertension may be more prone to develop hypotension as a consequence of opioid administration under general anesthesia. The hemodynamic and bispectral index responses to a remifentanil bolus in neurosurgical hypertensive patients under target-controlled infusion with propofol and remifentanil are addressed. Ten healthy patients and 10 patients with diagnosed hypertension under pharmacological treatment were studied. A 2 µg/kg remifentanil bolus was administered to all patients before skin incision under target-controlled infusion with propofol and remifentanil. Mean arterial pressure, heart rate, and the area under the curve for the bispectral index of the electroencephalogram were analyzed within the groups and compared between them every 30 seconds for two minutes following the bolus. Two minutes after the remifentanil bolus, remifentanil predicted effect-site concentrations reached maximum values of 8.46±0.91 ng/ml and 9.74±1.29 ng/ml in the healthy and hypertensive patients, respectively. Both groups showed a significant decrease in mean arterial pressure, heart rate, and in the area under the curve for the bispectral index. Mean arterial pressure decreased by 17.3±10% and 24±9%, heart rate by 11.1±8% and 12±8%, and the bispectral index by 13±9.2% and 8.6±8.4% in the healthy and hypertensive patients, respectively, 120 seconds after the remifentanil bolus. In a clinical situation in which high remifentanil doses may be required, hypertensive patients are expected to have hemodynamic and bispectral index responses similar to those observed in healthy patients.info:eu-repo/semantics/publishedVersio

A step towards effect-site target-controlled infusion with propofol in dogs: a ke0 for propofol

Target-controlled infusion (TCI) anesthesia using target effect-site concentration rather than plasma concentration provides less drug consumption, safer anesthesia, less undesired side effects and improved animal welfare. The aim of this study was to calculate the constant that converts propofol plasma into effect-site concentration (ke0) in dogs, and to implement it in a TCI system and compare it with the effect on the central nervous system (CNS). All dogs were subjected to general anesthesia using propofol. Fourteen dogs were used as the pilot group to calculate ke0, using the tpeak method. Fourteen dogs were used as the test group to test and validate the model. Rugloop ii® software was used to drive the propofol syringe pump and to collect data from S/5 Datex monitor and cerebral state monitor. The calculated ke0 was incorporated in an existing pharmacokinetic model (Beths Model). The relationship between propofol effect site concentrations and anesthetic planes, and propofol plasma and effect-site concentrations was compared using Pearson’s correlation analysis. Average tpeak was 3.1 min resulting in a ke0 of 0.7230 min−1. The test group showed a positive correlation between anesthetic planes and propofol effect-site concentration (R = 0.69; P < 0.0001). This study proposes a ke0 for propofol with results that demonstrated a good adequacy for the pharmacokinetic model and the measured effect. The use of this ke0 will allow an easier propofol titration according to the anesthetic depth, which may lead to a reduction in propofol consumption and less undesired side effects usually associated to high propofol concentrations in dogs.The authors would like to acknowledge the Fundação para a Ciência e a Tecnologia (FCT – Lisboa, Portugal) and the Project POCTI⁄CVT ⁄559056 ⁄2004. The C. S. Nunes would like to acknowledge UISPA-IDMEC.info:eu-repo/semantics/publishedVersio

On the stability of the set of hyperbolic closed orbits of a hamiltonian

A Hamiltonian level, say a pair $(H,e)$ of a Hamiltonian $H$ and an energy $e \in \mathbb{R}$, is said to be Anosov if there exists a connected component $\mathcal{E}_{H,e}$ of $H^{-1}({e})$ which is uniformly hyperbolic for the Hamiltonian flow $X_H^t$. The pair $(H,e)$ is said to be a Hamiltonian star system if there exists a connected component $\mathcal{E}^\star_{H,e}$ of the energy level $H^{-1}({{e}})$ such that all the closed orbits and all the critical points of $\mathcal{E}^\star_{H,e}$ are hyperbolic, and the same holds for a connected component of the energy level $\tilde{H}^{-1}({\tilde{e}})$, close to $\mathcal{E}^\star_{H,e}$, for any Hamiltonian $\tilde{H}$, in some $C^2$-neighbourhood of $H$, and $\tilde{e}$ in some neighbourhood of $e$. In this article we prove that for any four-dimensional Hamiltonian star level $(H,e)$ if the surface $\mathcal{E}^\star_{H,e}$ does not contain critical points, then $X_H^t|_{\mathcal{E}^\star_{H,e}}$ is Anosov; if $\mathcal{E}^\star_{H,e}$ has critical points, then there exists $\tilde{e}$, arbitrarily close to $e$, such that $X_H^t|_{\mathcal{E}^\star_{H,\tilde{e}}}$ is Anosov.info:eu-repo/semantics/publishedVersio

Stella Vitae. Cantata

Orquestração de Dionísio Vila MaiorOrquestração de "Stella Vitae. Cantata". Música, letra e harmonização vocal de Dionísio Vila MaiorN/

De Kafka a Kundera: Praga, capital literária

Recursos Educativos - HumanidadesEscritores que viveram e escreveram na cidade de Praga: Franz Kafka; Rainer Maria Rilke; Bohumil Hrabal; Milan Kundera. Depoimentos dos professores Luís Carlos Gonçalves e Gerald Bär, docentes da Universidade Aberta.info:eu-repo/semantics/publishedVersio

Learning space for management education

Material pedagógico para a unidade curricular: Gestão da Inovação do Conheciment

O povoado pré-histórico de Leceia (Oeiras) : síntese de vinte anos de escavações arqueológicas (1983-2002)

O povoado pré-histórico de Leceia é conhecido no mundo científico desde 1878, altura em que o General Carlos Ribeiro, pioneiro da Pré-História e da Geologia portuguesas, sobre ele publicou uma extensa e bem documentada memória, apresentada à Academia Real das Ciências de Lisboa, que pode considerar-se a primeira monografia dedicada a um povoado pré-histórico português. Apesar de a estação ser, desde então, frequentemente referida em trabalhos da especialidade, tanto em Portugal como no estrangeiro - Leite de Vasconcelos dedicou-lhe, em 1917, artigo publicado nas páginas de "0 Arqueólogo Português" com o título expressivo de "Arqueologia liceense" - jamais, até ao início da intervenção ali iniciada por iniciativa do signatário, se tinham ali realizado escavações. Apenas Joaquim Fontes publicou, em 1955, os resultados sumários de pequenas valas de prospecção que ali executou, em colaboração com o Escultor Alvaro de Brée, este último durante décadas coleccionador de materiais arqueológicos obtidos pelo próprio ou por naturais da região, tal como havia acontecido anteriormente com Abílio Rozeira, na década de 1920; tais materiais estudados e publicados pelo signatário em 1980 e 1981 , já depois de se ter dedicado à minuciosa prospecção do terreno, realizada em inumeráveis visitas ao local, desde 1970, ano em que lhe fora oferecida a monografia de Carlos Ribeiro, oferecida pelo próprio a seu trisavô, antigo Ministro e Presidente da Associação dos Arqueólogos Portugueses, o Conselheiro Augusto José da Cunha

A multi-agent approach for web adaptation

Web growth has brought several problems to users. The large amount of information that exists nowadays in some particular Websites turns the task of finding useful information very difficult. Knowing users’ visiting pattern is crucial to owners, so that they may transform or customize the Website. This problem originated the concept known as Adaptive Website: a Website that adapts itself for the purpose of improving the user’s experience. This paper describes a proposal for a doctoral thesis. The main goal of this work is to follow a multi-agent approach for Web adaptation. The idea is that all knowledge administration about the Website and its users, and the use of that knowledge to adapt the site to fulfil user’s needs, are made by an autonomous intelligent agent society in a negotiation environment. The complexity of the problem and the inherently distributed nature of the Web, which is an open, heterogeneous and decentralized network, are reasons that justify the multi-agent approach. It is expected that this approach enables real-time Web adaptation with a good level of benefit to the users.info:eu-repo/semantics/publishedVersio

Emissão de sábado, dia 18 de abril de 2009

Emissões - TemáticasVídeo Institucional da Universidade Aberta, produzido em 2009. Entrevista ao professor Luís Carlos Gonçalves, docente da Universidade Aberta e autor do videograma “De Kafka a Kundera: Praga, capital literária”. Videograma "De Kafka a Kundera: Praga, capital literária": Escritores que viveram e escreveram na cidade de Praga: Franz Kafka; Rainer Maria Rilke; Bohumil Hrabal; Milan Kundera, com depoimentos dos professores Luís Carlos Gonçalves e Gerald Bär, docentes da Universidade Aberta. Clip documental: “As Palavras no Lugares: Santa Apolónia”. Santa Apolónia e a poesia de Álvaro de Campos. Notícias: “1º Curso de Formação Integrada em Elearning”, dia 25 de março de 2009, na Reitoria da Universidade Técnica de Lisboa, no âmbito do protocolo de colaboração, assinado a 8 de maio de 2008, entre a Universidade Aberta e a Universidade Técnica de Lisboa: Reportagem da cerimónia de abertura, com depoimentos de Fernando Ramôa Ribeiro, Reitor da Universidade Técnica de Lisboa, de Carlos Reis, Reitor da Universidade Aberta, de Helena Pereira, Vice-reitora da Universidade Técnica de Lisboa, de António Teixeira, Pró-reitor da Universidade Aberta, de Ana Lucas, do Instituto Superior de Economia e Gestão, de Esmeralda Delgado, da Faculdade de Medicina Veterinária e de Leonel Fadigas, da Faculdade de Arquitetura. Clip documental: “As Palavras nos Lugares: Palácio Ceia”. O Palácio Ceia, sede da Universidade Aberta em Lisboa, com as palavras do poeta Correia Garção.info:eu-repo/semantics/publishedVersio