Desenvolvimento de um Repositório de Imagens e Base de Dados Portuguesa de Casos COVID-19: Aprendizagem e Partilha de Conhecimento em Tempo de Pandemia

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Bacillary Angiomatosis by Bartonella Quintana in an HIV-Infected Patient

Bacillary angiomatosis and bacillary peliosis are opportunistic infections caused by Bartonella henselae and Bartonella quintana, which occur in patients with late-stage infection. We report a case of bacillary angiomatosis in an HIV-infected patient with skin, bone, and probably liver involvement, The identification of the agent (B quintana ) was done by polymerase chain reaction in the skin specimen. The patient had complete regression of all lesions after a 6-month regimen of oral erythromycin

Acoustic behaviour of GFRP-PUR web-core composite sandwich panels

This paper presents an experimental and analytical study about the sound insulation of innovative sandwich panels - named EasyFloor – _for the rehabilitation of degraded timber floors in old buildings. Two types of panels were developed: (i) an all-composite sandwich panel, made of glass fibre reinforced polymer (GFRP) face sheets and webs, and polyurethane (PUR) foam; (ii) and a hybrid sandwich panel, where the top face sheet comprises a thin layer of concrete. The study included the comparative analysis of the airborne sound reduction and impact sound pressure level of both types of panels based on experimental tests on full-scale specimens, including a typical floor covering. The acoustic insulation properties determined experimentally were compared with predictions from different analytical models typically applied to sandwich panels, and also with performance requirements defined in building regulation. Among the different analytical models that were assessed, Sharp’s model provided the most accurate predictions when considering the natural and dilatation frequencies as the critical frequency. The comparison of the normalized airborne and impact sound indices determined experimentally with requirements set in building regulation shows that the use of GFRP-PUR panels in the rehabilitation of lightweight timber floors and in new construction, where building comfort requirements are stricter, require mitigation measures to improve sound insulation

Graphene nanoribbons and nanoflakes from functionalized carbon precursors

The process of formation of graphene by exfoliation of carbon nanotubes (CNT) or graphite originates graphene nanoribbons (GNR) and graphene nanoflakes (GNF), respectively. These nanoparticles are expected to present interesting electronic properties, depending on their shape, size, and on their edge shape. Several methods for the unzipping of nanotubes were described in the literature [1]. The major limitations to the application of these methods are related to low yield, or to the formation of highly oxidized GNRs. The present work was motivated by the observation of the unzipping of functionalized CNT under ultra-high vacuum scanning tunneling microscopy (UHV STM) [2]. The CNTs under observation were functionalized by the 1,3-dipolar cycloaddition reaction [3], a potential route for the production of GNRs without oxidation. The formation of graphene flakes was observed when functionalized graphite was exfoliated under similar conditions as the CNT. The graphite was functionalized by the same procedure as the CNT.Fundação para a Ciência e a Tecnologia (FCT

What Makes a Pediatrician a Neonatologist

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