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TB is a public health problem, and its diagnosis can be challenging. Among imaging methods, chest X-ray (CXR) is the leading choice for assessing pulmonary TB (PTB). Recent advancements in the field of artificial intelligence have stimulated studies evaluating the performance of machine learning (ML) for medical diagnosis. This study validated a new original Brazilian tool, the XmarTB, applied to CXR images to support the early diagnosis of PTB.An ML model was trained on 3,800 normal images, 3,800 abnormal CXRs without PTB and 1,376 with PTB manifestations from the publicly available TBX11K database.The binary classification can distinguish between normal and abnormal CXR with a sensitivity of 99.4% and specificity of 99.4%. The XmarTB tool had a sensitivity of 98.1% and a specificity of 99.7% in detecting TB cases among CXRs with abnormal CXRs; sensitivity was 96.7% and specificity 98.7% in detecting TB cases among all samples.This diagnostic tool can accurately and automatically detect abnormal CXRs and satisfactorily differentiate PTB from other pulmonary diseases. This tool holds significant promise in aiding the proactive detection of TB cases, providing rapid and accurate support for early diagnosis..

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Social facilities such residential structures and day-centres increasingly seek integrated, structured, adapted, creative, dynamic and economic strategies to prevent frailty. The arising need of an aged and frail population requires innovative interventions and products to prevent cognitive and physical decline. The interregional MIND&GAIT project aims to promote independent living in frail older adults by improving cognition and gait ability by using assistive products. This transdisciplinary strategy within a 24-months period expects as project' deliverables: i) a structured and good practice-based combined intervention (CI) consisting of a cognitive stimulation programme and a physical exercise programme; ii) an auto-blocking mechanism for rolling walkers with biofeedback acquisition (ABMRW); iii) a randomized clinical trial to assess CI' effectiveness; and iv) a web-platform to be used as a repository that will support and disseminate the intervention materials, covering the action-line of translational research. Positive benefits are expected in prevention and maintenance of frail older adults' capacities. Preliminary results showed positive effects on the improvement of cognitive and physical functions, functionality and depressive symptomatology. The interregional geographical coverage induced by MIND&GAIT underlines the potential replicability of the project extension to the community in the Centro and Alentejo regions of Portugal. MIND&GAIT network supports actions and provides learning opportunities and emergence of locally-embedded support systems towards social innovation for older adults.

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The strength of binding between the Helicobacter pylori blood group antigen-binding adhesin (BabA) and its cognate glycan receptor, the Lewis b blood group antigen (Le(b)), was measured by means of atomic force microscopy. High-resolution measurements of rupture forces between single receptor-ligand pairs were performed between the purified BabA and immobilized Le(b) structures on self-assembled monolayers. Dynamic force spectroscopy revealed two similar but statistically different bond populations. These findings suggest that the BabA may form different adhesive attachments to the gastric mucosa in ways that enhance the efficiency and stability of bacterial adhesion.

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Helicobacter pylori colonizes the gastric mucosa of half of the worlds population and persistent infection is related with an increase in the risk of gastric cancer. Adhesion of H. pylori to the gastric epithelium, which is essential for infection, is mediated by bacterial adhesin proteins that recognize specific glycan structures (Gly-R) expressed in the gastric mucosa. The blood group antigen binding adhesin (BabA) recognizes difucosylated antigens such as Lewis B (Leb), while the sialic acid binding adhesin (SabA) recognizes sialylated glycoproteins and glycolipids, such as sialyl-Lewis x (sLex). This work aimed to investigate whether these Gly-Rs (Leb and sLex) can attract and specifically bind H. pylori after immobilization on synthetic surfaces (self-assembled monolayers (SAMs) of alkanethiols on gold). Functional bacterial adhesion assays for (Gly-R)-SAMs were performed using H. pylori strains with different adhesin protein profiles. The results demonstrate that H. pylori binding to surfaces occurs via interaction between its adhesins and cognate (Gly-R)-SAMs and bound H. pylori maintains its characteristic rod-shaped morphology only during conditions of specific adhesin-glycan binding. These results offer new insights into innovative strategies against H. pylori infection based on the scavenging of bacteria from the stomach using specific H. pylori chelating biomaterials.

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An outbreak of dengue fever in Madeira island was reported in 2012. Clinical and laboratory findings of the first two laboratory-confirmed autochthonous cases are reported. Both cases had fever (≥38 °C) and petechial rash. Symptoms also included myalgia, asthenia, nausea, vomiting, anorexia, diffuse abdominal pain, and diarrhoea. The two cases were confirmed by serology and one tested positive for a dengue viral sequence. Dengue virus serotype DEN-1 was identified with probable Central or South American origin.

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Toscana virus (TOSV) is an emerging Phlebovirus of growing interest as a human pathogen in the Mediterranean Basin. In Portugal, however, little is known about the prevalence of TOSV infection. The aim of this work was to perform a seroprevalence study in patients with requests for laboratory diagnosis of vector-borne viruses. A total of 538 patients with and without neurological signs from 2004 to 2008 were studied by in-house indirect immunofluorescence assay and commercial enzyme-linked immunosorbent assays. A prevalence of 4.2% for IgG antibodies was found in the group of patients with neurological signs. Five (3%) of these had recent infections. In the group with no neurological signs, the IgG prevalence was 1.3%. Two samples, belonging to two patients, were also confirmed with plaque reduction neutralization tests with the TOSV ISS. Phl.3 Italian strain. This work showed that TOSV is present and causing disease from north to south in Portugal. The probable circulation of different phlebovirus serotypes in Portugal emphasizes the need for further studies.

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This work identified, quantified, and presents results for metals in water using a portable energy dispersive X-ray fluorescence (EDXRF) system. It was possible to quantify the following range of concentrations in mg L(-1): Ca(0.043-0.021), Ti(0.137-0.014), Mn(0.052-0.008), Fe(1.66-0.035), Ni(0.012-0.010), Cu(0.010-0.007), Zn(0.070-0.007), and Pb(1.01-0.85). The final conclusion is that in 4h of field work it was possible to prepare, measure, and analyze 14 membranes.

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Conductive and transparent undoped thin films of indium oxide (InOx ), 120 nm average thick, were deposited by radio frequency plasma enhanced reactive thermal evaporation (rf-PERTE) of indium in the presence of oxygen at room temperature. Several substrates were used in order to study their influence on the main properties of these films: alkali free (AF) glass, fused silica, crystalline silicon and polyethylene terephthalate (PET). Surface morphology of the InOx films as a function of the substrates was observed by SEM and showed that the undoped InOx films obtained are nanostructured. For the c-Si substrate, InOx films with increased grain size are obtained, induced by the crystalline substrate. Films deposited on fused silica and AF glass substrates show a nano-grainy surface with similar surface morphologies. The InOx films deposited on AF glass show the highest values of both: electrical conductivity of about 1100 (omega cm)(-1) and visible transmittance of 85%. The substrate has a greater influence on the surface morphology of the films when a polymer (PET) is used. InOx films deposited on PET show a decrease in the electrical conductivity (90 (omega cm)(-1)) and a slight decrease in the average visible transmittance (78%).

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Preconcentration of heavy metals in water with ammonium pyrrolydine dithiocarbamate (APDC) is a common practice in analytical chemistry. A literature review on this topic showed that several authors use this precipitation agent, but in different preconcentration conditions, conducting to divergent results. The objective of this work is to use factorial design to optimize the factors involved in the preconcentration process of heavy metals using APDC. Five factors were studied: sample volume, solution pH, APDC concentration, APDC volume and stirring time. The assays were performed by energy dispersive X-ray fluorescence (EDXRF). The values for detection limits within 95% confidence level, in microg L(-1), were: Fe (6.0+/-0.1), Cu (4.0+/-0.1), Zn (2.0+/-0.1), Se (4.0+/-0.1) and Pb (5.0+/-0.1). The value for quantification limit for the five elements was 20 microg L(-1), with 3% deviation. Multi-element standard solutions were prepared. Precipitation procedure was applied in the spiked solutions and the samples were filtered in cellulose ester membrane for quantification measurements. The optimum values obtained were 300 mL of sample solution, pH 4, 1 mL of 2% APDC and 10 min of stirring time. The concentration results obtained for the validation measurements were satisfactory for in situ survey employing a portable instrument.

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An X-ray tube with a Mo target and Zr filter, operated at 45 kV/20 mA, was used to excite samples (5 microL deposited on a quartz support) and the total reflection angle condition was obtained with a double reflector module built with two 10-cm-long 7-mm-thick quartz crystals placed 50 microns apart. A high-resolution spectrometer based on a Si(Li) detector coupled to a multichannel analyzer was used for X-ray detection and the spectra were interpreted with the AXIL software. The system was calibrated with standard chemical solutions containing Cr, Fe, Cu, Zn, and Pb, and Y was used as an internal standard to correct eventual geometric errors and high-voltage instabilities of the X-ray generator. The limits of detection were 19, 9, 5, and 4 ng/mL for Cr, Fe, Cu, and Zn, respectively, analyzed through characteristic K alpha X-rays, and 7 ng/mL for Pb, through L alpha X-rays, considering 50 microL samples deposited and dried on a quartz support, to be excited/detected for 1000 s.

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