31 documents found, page 1 of 4
Quaternion Hyperbolic Fourier Transforms and uncertainty principles
Ferreira, M.; Morais, J.The present study introduces the two-sided and right-sided Quaternion Hyperbolic Fourier Transforms (QHFTs) for analyzing two-dimensional qua\-ternion-valued signals defined in an open rectangle of the Euclidean plane endowed with a hyperbolic measure. The different forms of these transforms are defined by replacing the Euclidean plane waves with the corresponding hyperbolic plane waves in one dimension, giving...
Quaternion Hyperbolic Fourier Transforms and Uncertainty Principles
Ferreira, M.; Morais, J.The present study introduces the two-sided and right-sided Quaternion Hyperbolic Fourier Transforms (QHFTs) for analyzing two-dimensional quaternion-valued signals defined in an open rectangle of the Euclidean plane endowed with a hyperbolic measure. The different forms of these transforms are defined by replacing the Euclidean plane waves with the corresponding hyperbolic plane waves in one dimension, giving t...
Hyperbolic linear canonical transforms of quaternion signals and uncertainty
Morais, J.; Ferreira, M.This paper is concerned with Linear Canonical Transforms (LCTs) associated with two-dimensional quaternion-valued signals defined in an open rectangle of the Euclidean plane endowed with a hyperbolic measure, which we call Quaternion Hyperbolic Linear Canonical Transforms (QHLCTs). These transforms are defined by replacing the Euclidean plane wave with a corresponding hyperbolic relativistic plane wave in one d...
“Os cidadãos querem ser informados”: estudo de caso sobre o papel do design no ...
Morais, J.; Burrows, Alison; Trigueiros, PaulaGovernos em todo o mundo estão gradualmente disponibilizando os seus dados não confidenciais em plata-formas online, para facilitar o acesso público a essas informações. Porém, a maior parte das plataformas de Dados Aberto do Governo (DAG) não são tão inclusivas quanto se propõem pois, apesar da ênfase política no “envolvimento do cidadão”, seus verdadeiros usuários são profissionais técnicos. Este trabalho usa...
Metagenomic sequencing with spiked primer enrichment for viral diagnostics and ...
Deng, X.; Achari, A.; Federman, S.; Yu, G.; Somasekar, S.; Bártolo, I.; Yagi, S.; Mbala-Kingebeni, P.; Kapetshi, J.; Ahuka-Mundeke, S.Metagenomic next-generation sequencing (mNGS), the shotgun sequencing of RNA and DNA from clinical samples, has proved useful for broad-spectrum pathogen detection and the genomic surveillance of viral outbreaks. An additional target enrichment step is generally needed for high-sensitivity pathogen identification in low-titre infections, yet available methods using PCR or capture probes can be limited by high c...
Characterization of planktonic and biofilm cells from two filamentous cyanobact...
Romeu, M.J.L.; Domínguez-Pérez, D.; Almeida, D.; Morais, J.; Campos, A.; Vasconcelos, V.; Mergulhão, F.J.M.Cyanobacteria promote marine biofouling with significant impacts. A qualitative proteomic analysis, by LC-MS/MS, of planktonic and biofilm cells from two cyanobacteria was performed. Biofilms were formed on glass and perspex at two relevant hydrodynamic conditions for marine environments (average shear rates of 4 s−1 and 40 s−1). For both strains and surfaces, biofilm development was higher at 4 s−1. Biofilm de...
The relative importance of shear forces and surface hydrophobicity on biofilm f...
Faria, S.I.; Teixeira-Santos, R.; Romeu, M.J.; Morais, J.; Vasconcelos, V.; Mergulhão, F.J.Understanding the conditions affecting cyanobacterial biofilm development is crucial to develop new antibiofouling strategies and decrease the economic and environmental impact of biofilms in marine settings. In this study, we investigated the relative importance of shear forces and surface hydrophobicity on biofilm development by two coccoid cyanobacteria with different biofilm formation capacities. The strong...
Experimental assessment of the performance of two marine coatings to curb biofi...
Faria, S.I.; Teixeira-Santos, R.; Gomes, L.C.; Silva, E.R.; Morais, J.; Vasconcelos, V.; Mergulhão, F.J.M.Biofilms formed on submerged marine surfaces play a critical role in the fouling process, causing increased fuel consumption, corrosion, and high maintenance costs. Thus, marine biofouling is a major issue and motivates the development of antifouling coatings. In this study, the performance of two commercial marine coatings, a foul-release silicone-based paint (SilRef) and an epoxy resin (EpoRef), was evaluated...
Chlorosphaerolactylates A−D: Natural lactylates of chlorinated fatty acids isol...
Gutiérrez-Del-Río, I.; de Fraissinette, N.B.; Castelo-Branco, R.; Oliveira, F.; Morais, J.; Redondo-Blanco, S.; Villar, C.J.; José Iglesias, M.Four natural lactylates of chlorinated fatty acids, chlorosphaerolactylates A−D (1−4), were isolated from the methanolic extract of the cyanobacterium Sphaerospermopsis sp. LEGE 00249 through a combination of bioassay-guided and MS-guided approaches. Compounds 1−4 are esters of (mono-, di-, or tri)chlorinated lauric acid and lactic acid, whose structures were assigned on the basis of spectrometric and spectrosc...
Assessment of constructed wetlands' potential for the removal of cyanobacteria ...
Bavithra, G.; Azevedo, J.; Oliveira, F.; Morais, J.; Pinto, E.; Ferreira, I.M.P.L.V.O.; Vasconcelos, V.; Campos, A.; Almeida, C.M.R.Microcystis blooms and the subsequent release of hepatotoxic microcystins (MCs) pose a serious threat to the safety of water for human and livestock consumption, agriculture irrigation, and aquaculture worldwide. Microcystin-LR (MC-LR), the most toxic variant of MCs, has been widely detected in a variety of environments such as water, sediments, plants, and many aquatic organisms. Conventional solutions of wate...