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1.
J Cardiovasc Electrophysiol ; 33(8): 1725-1733, 2022 08.
Artigo em Inglês | MEDLINE | ID: mdl-35637604

RESUMO

PURPOSE: Since the widespread availability of contact-force sensing catheters, the need for a waiting period after pulmonary vein isolation (PVI) has not been reassessed. We aim to evaluate whether a waiting period is still necessary after PVI guided by the ablation Index (AI). METHODS: Prospective, multicenter, randomized study of consecutive patients referred for paroxysmal atrial fibrillation (AF) ablation from May 2019 to February 2020. Patients were randomized in a 1:1 ratio to PVI with versus without a waiting period of 20 min. Acute pulmonary vein (PV) reconnection after adenosine challenge was the primary endpoint. A per-protocol analysis was designed to determine whether a strategy of dismissing the waiting period after PVI was noninferior to waiting for 20 min for identifying acute PV reconnection. PVI was guided by tailored AI values and an interlesion distance ≤6 mm. RESULTS: During the enrollment period, 167 patients (56% males, mean age of 57 ± 14 years) fulfilled the study inclusion criteria - 84 patients (308 PV) in the waiting period group (Group A) and 83 patients (314 PV) in the group without a waiting period (Group B). Acute PV reconnection was identified in 3.8% (95% confidence interval [CI], 1.7%-5.9%) of PVs in the study group B compared to 2.9% (95% CI, 1.0%-4.8%) of PVs in the Group A (p = .002 for non-inferiority). At 1-year follow-up, there was no significant difference in arrhythmia recurrence between groups (9.5% in Group A vs. 9.6% in Group B, hazard ratio: 1.03 [95% CI, 0.39-2.73], p = .98). CONCLUSION: In paroxysmal AF patients submitted to ablation, a tailored PVI guided by the AI rendered a 20-min waiting period unnecessary.


Assuntos
Fibrilação Atrial , Ablação por Cateter , Veias Pulmonares , Adulto , Idoso , Fibrilação Atrial/diagnóstico , Fibrilação Atrial/cirurgia , Ablação por Cateter/efeitos adversos , Ablação por Cateter/métodos , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Estudos Prospectivos , Veias Pulmonares/cirurgia , Recidiva , Software , Resultado do Tratamento
2.
Biol Open ; 8(12)2019 Dec 18.
Artigo em Inglês | MEDLINE | ID: mdl-31852657

RESUMO

Information transfer between individuals typically depends on multiple sensory channels. Yet, how multi-sensory inputs shape adaptive behavioural decisions remains largely unexplored. We tested the relative importance of audio and visual sensory modalities in opponent size assessment in the vocal cichlid fish, Metriaclima zebra, by playing back mismatched agonistic sounds mimicking larger or smaller opponents during fights of size-matched males. Trials consisted in three 5-min periods: PRE (visual), PBK (acoustic+visual) and POST (visual). During PBK agonistic sounds of smaller (high frequency or low amplitude) or larger (low frequency or high amplitude) males were played back interactively. As a control, we used white noise and silence. We show that sound frequency but not amplitude affects aggression, indicating that spectral cues reliably signal fighting ability. In addition, males reacted to the contrasting audio-visual information by giving prevalence to the sensory channel signalling a larger opponent. Our results suggest that fish can compare the relevance of information provided by different sensory inputs to make behavioural decisions during fights, which ultimately contributes to their individual fitness. These findings have implications for our understanding of the role of multi-sensory inputs in shaping behavioural output during conflicts in vertebrates.

3.
Hist. ciênc. saúde-Manguinhos ; Hist. ciênc. saúde-Manguinhos;24(1): 165-185, jan.-mar. 2017. graf
Artigo em Português | LILACS | ID: biblio-840691

RESUMO

Resumo Analisa como a inovação responsável é discutida e implementada no contexto de uma das principais ações de fomento à nanotecnologia do governo português. Por meio da teoria do ator-rede e da sociologia das ausências, investigamos o processo de coprodução do International Iberian Nanotechnology Laboratory para identificar como preocupações quanto ao desenvolvimento responsável têm sido implementadas ou ausentadas nas normas e práticas. O instituto foi concebido a partir de um imaginário sociotécnico que o vislumbra como unidade autônoma de produção de inovações tecnológicas voltadas exclusivamente para o aumento da competitividade num mercado global, o que tem servido como obstáculo para práticas robustas de desenvolvimento responsável.


Abstract This article analyzes how responsible innovation has been discussed and implemented in the context of one of the Portuguese government’s main activities to foster nanotechnology. Through the actor-network theory and the sociology of absences, we investigate the process of coproduction at the International Iberian Nanotechnology Laboratory to identify how concerns about responsible development have been implemented or ignored in the rules and practices. The institute emerged from a sociotechnical imagination that views it as an autonomous unit for producing technological innovations aimed exclusively at increasing competitiveness in a global market, which has been an obstacle to the materialization of robust responsible development practices.


Assuntos
Humanos , Desenvolvimento Tecnológico , Nanotecnologia , Academias e Institutos , Invenções , Portugal
4.
J Acoust Soc Am ; 138(6): 3941-50, 2015 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-26723348

RESUMO

The study of acoustic communication in animals often requires not only the recognition of species specific acoustic signals but also the identification of individual subjects, all in a complex acoustic background. Moreover, when very long recordings are to be analyzed, automatic recognition and identification processes are invaluable tools to extract the relevant biological information. A pattern recognition methodology based on hidden Markov models is presented inspired by successful results obtained in the most widely known and complex acoustical communication signal: human speech. This methodology was applied here for the first time to the detection and recognition of fish acoustic signals, specifically in a stream of round-the-clock recordings of Lusitanian toadfish (Halobatrachus didactylus) in their natural estuarine habitat. The results show that this methodology is able not only to detect the mating sounds (boatwhistles) but also to identify individual male toadfish, reaching an identification rate of ca. 95%. Moreover this method also proved to be a powerful tool to assess signal durations in large data sets. However, the system failed in recognizing other sound types.


Assuntos
Acústica , Batracoidiformes/fisiologia , Reconhecimento Automatizado de Padrão , Comportamento Sexual Animal , Processamento de Sinais Assistido por Computador , Acústica da Fala , Medida da Produção da Fala/métodos , Vocalização Animal , Animais , Batracoidiformes/classificação , Ecossistema , Humanos , Masculino , Cadeias de Markov , Modelos Teóricos , Espectrografia do Som
5.
BMC Res Notes ; 6: 25, 2013 Jan 22.
Artigo em Inglês | MEDLINE | ID: mdl-23339526

RESUMO

BACKGROUND: Sequencing-by-synthesis technologies significantly improve over the Sanger method in terms of speed and cost per base. However, they still usually fail to compete in terms of read length and quality. Current high-throughput implementations of the pyrosequencing technique yield reads whose length approach those of the capillary electrophoresis method. A less obvious question is whether their quality is affected by platform-specific sequencing errors. RESULTS: We present an empirical study aimed at assessing the quality and characterising sequencing errors for high throughput pyrosequencing data. We have developed a procedure for extracting sequencing error data from genome assemblies and study their characteristics, in particular the length distribution of indel gaps and their relation to the sequence contexts where they occur. We used this procedure to analyse data from three prokaryotic genomes sequenced with the GS FLX technology. We also compared two models previously employed with success for peptide sequence alignment. CONCLUSIONS: We observed an overall very low error rate in the analysed data, with indel errors being much more abundant than substitutions. We also observed a dependence between the length of the gaps and that of the homopolymer context where they occur. As with protein alignments, a power-law model seems to approximate the indel errors more accurately, although the results are not so conclusive as to justify a depart from the commonly used affine gap penalty scheme. In whichever case, however, our procedure can be used to estimate more realistic error model parameters.


Assuntos
Artefatos , Genoma Bacteriano , Sequenciamento de Nucleotídeos em Larga Escala/estatística & dados numéricos , Modelos Estatísticos , Algoritmos , Sequência de Bases , Mutação INDEL , Dados de Sequência Molecular , Mycoplasma hyopneumoniae/genética , Alinhamento de Sequência , Staphylococcus aureus/genética , Streptococcus pneumoniae/genética
6.
Bioinformatics ; 24(16): i160-6, 2008 Aug 15.
Artigo em Inglês | MEDLINE | ID: mdl-18689819

RESUMO

MOTIVATION: Position weight matrices (PWMs) have become a standard for representing biological sequence motifs. Their relative simplicity has favoured the development of efficient algorithms for diverse tasks such as motif identification, sequence scanning and statistical significance evaluation. Markov chainbased models generalize the PWM model by allowing for interposition dependencies to be considered, at the cost of substantial computational overhead, which may limit their application. RESULTS: In this article, we consider two aspects regarding the use of higher order Markov models for biological sequence motifs, namely, the representation and the computation of P-values for motifs described by a set of occurrences. We propose an efficient representation based on the use of tries, from which empirical position-specific conditional base probabilities can be computed, and extend state-of-the-art PWM-based algorithms to allow for the computation of exact P-values for high-order Markov motif models. AVAILABILITY: The software is available in the form of a Java objectoriented library from http://www.cin.ufpe.br/approxiamtely paguso/kmarkov.


Assuntos
Algoritmos , Modelos Químicos , Modelos Genéticos , Análise de Sequência/métodos , Simulação por Computador , Interpretação Estatística de Dados , Cadeias de Markov , Modelos Estatísticos
7.
Rev. adm. pública ; 25(4): 25-32, out.-dez. 1991.
Artigo em Português | LILACS | ID: lil-112940

RESUMO

A "crise ecológica" provoca questionamento da estratégia de desenvolvimento brasileiro centrada na industrializaçäo e quanto aos investimentos em controle de produçäo. O BNDES desempenha papel importante na induçäo do investimento ambiental em consonância com política ambiental brasileira.


Assuntos
Desenvolvimento Econômico/tendências , Política Ambiental/economia , Brasil , Conservação dos Recursos Naturais , Meio Ambiente , Órgãos Governamentais , Indústrias , Investimentos em Saúde/tendências
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