Browsing by resource type "contribution to journal"
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- A 1.7-mW −92-dBm Sensitivity Low-IF Receiver in 0.13-um CMOS for Bluetooth LE ApplicationsPublication . Silva-Perreira, Marco.; Sousa, J. T. de; Freire, J. Costa; Vaz, J. CaldinhasThis paper presents a 1.7-mW low-intermediate-frequency receiver design for Bluetooth low-energy (BLE) applications. The design exploits particular aspects of BLE, such as the relaxed in-band interference characteristics, more precisely the C/I1 MHz, and the relatively high-frequency-shift keying modulation index, to deliver a high level of energy efficiency and simplicity to the receiver baseband architecture. Reliable quadrature signals are generated in the RF signal path without consuming energy, which is supported by an inverter-based low-noise amplifier (LNA) that achieves high gain and low noise figure under low-power budgets. A small-signal analysis of low-power inverter-based LNAs is presented offering simple design equations. Seeking an affordable solution, the fabricated prototype is fully integrated into an earlier generation CMOS technology node (0.13 μm), occupying a silicon area smaller than 0.7 mm2. The receiver achieves a sensitivity level of -92 dBm while consuming 1.41 mA from a 1.2-V supply.
- The 2018 periodontitis case definition improves accuracy performance of full-mouth partial diagnostic protocolsPublication . Botelho, João; Machado, Vanessa; Proença, Luís; Mendes, José JoãoWe aimed to compare the accuracy performance of the new 2018 periodontitis case definition by the European Federation of Periodontology (EFP)/ American Association of Periodontology (AAP) with Centers for Disease Control (CDC)/AAP 2012 in full-mouth partial recording protocols (PRP). Retrospective data from NHANES 2011-2012 and 2013-2014 were analyzed. For each case definition, full-mouth diagnostic was defined as the reference standard. Patients were diagnosed for the presence of periodontitis and staging for each PRP. Sensitivity, specificity, accuracy and precision, through several indicators, were determined. Performance measurement was assessed through binary and multiclass ROC/AUC analyses. Our performance analysis shows that the new 2018 classification outperforms the 2012 classification regarding the diagnosis and staging of periodontitis on full-mouth PRPs. This recent case definition has strengthened the utility of PRPs and its improvements certainly explain the observed findings. Also, our findings contribute to the reliability of PRPs and its use in future worldwide epidemiological surveys.
- 3D bioprinting of novel κ-carrageenan bioinks : an algae-derived polysaccharidePublication . Marques, Diana M. C.; Silva, João C.; Serro, Ana Paula; Cabral, Joaquim M. S.; Sanjuan-Alberte, Paola; Ferreira, Frederico C.Novel green materials not sourced from animals and with low environmental impact are becoming increasingly appealing for biomedical and cellular agriculture applications. Marine biomaterials are a rich source of structurally diverse compounds with various biological activities. Kappa-carrageenan (κ-c) is a potential candidate for tissue engineering applications due to its gelation properties, mechanical strength, and similar structural composition of glycosaminoglycans (GAGs), possessing several advantages when compared to other algae-based materials typically used in bioprinting such as alginate. For those reasons, this material was selected as the main polysaccharide component of the bioinks developed herein. In this work, pristine κ-carrageenan bioinks were successfully formulated for the first time and used to fabricate 3D scaffolds by bioprinting. Ink formulation and printing parameters were optimized, allowing for the manufacturing of complex 3D structures. Mechanical compression tests and dry weight determination revealed young’s modulus between 24.26 and 99.90 kPa and water contents above 97%. Biocompatibility assays, using a mouse fibroblast cell line, showed high cell viability and attachment. The bioprinted cells were spread throughout the scaffolds with cells exhibiting a typical fibroblast-like morphology similar to controls. The 3D bio-/printed structures remained stable under cell culture conditions for up to 11 days, preserving high cell viability values. Overall, we established a strategy to manufacture 3D bio-/printed scaffolds through the formulation of novel bioinks with potential applications in tissue engineering and cellular agriculture.
- Accuracy of inertial measurement units when applied to the countermovement jump of track and field athletesPublication . Miranda-Oliveira, Paulo; Branco, Marco; Fernandes, OrlandoIn this study, we aimed to assess the countermovement jump (CMJ) using a developed instrument encompassing an off-the-shelf Inertial Measurement Unit (IMU) in order to analyze performance during the contraction phase, as well as to determine the jump height and the modified reactive strength index (RSImod), using force plate (FP) data as reference. Eight athletes (six males and two females) performed CMJs with the IMU placed on their fifth lumbar vertebra. Accuracy was measured through mean error (standard deviation), correlation, and comparison tests. The results indicated high accuracy, high correlation (r), and no statistical differences between the IMU and the FP for contraction time (r = 0.902; ρ < 0.001), negative impulse phase time (r = 0.773; ρ < 0.001), flight time (r = 0.737; ρ < 0.001), jump time (r = 0.708; ρ < 0.001), RSImod (r = 0.725; ρ < 0.001), nor minimum force (r = 0.758; ρ < 0.001). However, the values related to the positive impulse phase did not have the expected accuracy, as we used different devices and positions. Our results demonstrated that our developed instrument could be utilized to identify the contraction phase, jump height, RSImod, and minimum force in the negative impulse phase with high accuracy, obtaining a signal similar to that of an FP. This information can help coaches and athletes with training monitoring and control, as the device has simpler applicability making it more systematic.
- Accuracy of panoramic radiograph for diagnosing periodontitis comparing to clinical examinationPublication . Machado, Vanessa; Proença, Luís; Morgado, Mariana; Mendes, José João; Botelho, JoãoIn this study, we explore the diagnostic accuracy of a Radiographic-based Periodontal Bone Loss (R-PBL) method as a screening tool for periodontitis, in the form of radiographic bone loss, under the 2018 case definition in comparison to the 2012 case definition. The analysis was based on 456 patients (253 females and 203 males), screened for periodontal status in the Study of Periodontal Health in Almada-Seixal (SoPHiAS) project and subjected to a panoramic dental X-ray. Patients were diagnosed for the presence of periodontitis following the 2018 and 2012 case definition. R-PBL classification was defined by alveolar bone loss and diagnosed as no periodontitis (≥80% remaining alveolar bone), mild to moderate periodontitis (66% to 79%), or severe periodontitis (<66%). We appraise the X-ray quality to look for the influence on the performance of R-PBL. Sensitivity, specificity, accuracy, and precision, through several indicators, were determined. Performance measurement was assessed through binary and multiclass Receiver operating characteristic/are under the curve (ROC/AUC) analyses. Our results show that the tested R-PBL method under the 2018 case definition is a reliable tool in periodontitis cases screening. This method does not replace clinical periodontal evaluation, but rather, it screens patients towards a definitive periodontitis diagnosis. These results will contribute to support the development of automated prediction systems towards periodontitis surveillance.
- Acute kidney injury associated with COVID-19 infection : a case reportPublication . Duarte, Tiago; Caeiro, Fernando; Góis, Mário; Matos, António; Viana, Lena; Vieira, César; Paulos, Jorge; Paixão, Paulo; Matos, Bruno; Germano, Nuno; Nolasco, FernandoSARS-Cov2 infection is a highly transmissible disease associated with serious pulmonary disease. Renal involvement is frequent and associated with poor prognosis; however, mechanisms of kidney injury are not well established. We present a SARS-Cov2 patient with severe acute kidney injury. Kidney biopsy findings revealed a pattern of acute tubular necrosis with isometric vacuolization of the proximal tubule. The interstitium and glomeruli were normal. Electronic microscopy showed multiple viral-like particles in both the glomeruli and proximal tubule. This case study shows how SARS-Cov 2 infection can result in different kinds of kidney lesion.
- Adansonia digitata L. (Baobab fruit) effect on postprandial glycemia in healthy adults : a randomized controlled trialPublication . Rita, Keyla; Bernardo, Maria Alexandra; Silva, Maria Leonor; Brito, José; Mesquita, Maria Fernanda; Pintão, Ana Maria; Moncada, MargaridaBaobab fruits have been traditionally used in Africa due to their therapeutic properties attributed to their high polyphenol content. The aim of the study was to investigate the effect of baobab fruit on postprandial glycaemia in healthy adults and to measure its bioactive compounds and antioxidant activity. The study (NCT05140629) was conducted on 31 healthy subjects. The participants were randomly allocated in the control group (oral glucose tolerance test (OGTT); n = 16) and in the intervention group (OGTT, followed by administration of 250 mL baobab aqueous extract (BAE); n = 15). Total phenols, proanthocyanins, hydrolyzable tannins, and antioxidant activity (FRAP, DPPH, ABTS, and inhibition of O2•− and NO• methods) were quantified. Repeated measures ANOVA of mixed type and independent samples t-test were used. Glycemia incremental area under the curve (p = 0.012) and glucose maximum concentration (p = 0.029) was significantly lower in the intervention group compared to the control group. The BAE revealed high total contents of phenols, proanthocyanins, and hydrolyzable tannins, as well as a strong capacity to scavenge superoxide anions and nitric oxide radicals and a high antioxidant activity. In conclusion, this study encourages the use of this food component as a promising source of natural antioxidants and a hypoglycemic agent under glucose load acute conditions.
- Adaptation and Validation of the Instrument ‘Children Care Quality at Hospital’ for PortuguesePublication . Loureiro, Fernanda; Araújo, Beatriz; Charepe, ZaidaObjective: adapt and validate the instrument Children Care Quality at Hospital (CCQH) to assess the quality of nursing care of hospitalized children for the Portuguese language of Portugal. Materials and Methods: content, language, and conceptual validity methodological study, with translation, feedback, and reflection. A non-probabilistic simple was used of 252 children between 7 and 11 years of age, hospitalized due to acute disease in nine services of six Portuguese hospitals. The reliability and validity of the results were determined to measure the psychometric properties of the instrument. Construct validity was calculated through exploratory factor analysis of main components with Varimax rotation and the internal consistency by determining the Cronbach’s alpha coefficient. Results: the internal consistency has adequate psychometric characteristics suitable for the Portuguese population (Cronbach’s alpha values between 0.66 and 0.82). The instrument maintained 49 items grouped into three categories: characteristics, activities, and environment. The psychometric characteristics of the CCQH, adapted and validated for Portuguese, guarantees its reliability and validity to measure satisfaction with the quality of nursing care from the perspective of school-aged children. Conclusions: the instrument could be used to assess children’s satisfaction with the quality of nursing care during their hospitalization.
- Adverse outcome pathways associated with the ingestion of titanium dioxide nanoparticles : a systematic reviewPublication . Rolo, Dora; Assunção, Ricardo; Ventura, Célia; Alvito, Paula; Gonçalves, Lídia; Martins, Carla; Bettencourt, Ana; Jordan, Peter; Vital, Nádia; Pereira, Joana; Pinto, Fátima; Matos, Paulo; Silva, Maria João; Louro, HenriquetaTitanium dioxide nanoparticles (TiO2-NPs) are widely used, and humans are exposed through food (E171), cosmetics (e.g., toothpaste), and pharmaceuticals. The oral and gastrointestinal (GIT) tract are the first contact sites, but it may be systemically distributed. However, a robust adverse outcome pathway (AOP) has not been developed upon GIT exposure to TiO2-NPs. The aim of this review was to provide an integrative analysis of the published data on cellular and molecular mechanisms triggered after the ingestion of TiO2-NPs, proposing plausible AOPs that may drive policy decisions. A systematic review according to Prisma Methodology was performed in three databases of peer-reviewed literature: Pubmed, Scopus, and Web of Science. A total of 787 records were identified, screened in title/abstract, being 185 used for data extraction. The main endpoints identified were oxidative stress, cytotoxicity/apoptosis/cell death, inflammation, cellular and systemic uptake, genotoxicity, and carcinogenicity. From the results, AOPs were proposed where colorectal cancer, liver injury, reproductive toxicity, cardiac and kidney damage, as well as hematological effects stand out as possible adverse outcomes. The recent transgenerational studies also point to concerns with regard to population effects. Overall, the findings further support a limitation of the use of TiO2-NPs in food, announced by the European Food Safety Authority (EFSA).
- AI, optimization, and human values: mapping the intellectual landscape of industry 4.0 to 5.0Publication . Rosário, Albérico Travassos; Raimundo, RicardoThis study conducts a systematic bibliometric literature review to explore the conceptual and technological transition from Industry 4.0 to Industry 5.0, focusing on the roles of artificial intelligence (AI), optimization, and human values. Applying the PRISMA 2020 protocol, the analysis includes 53 peer-reviewed sources from the Scopus database, em phasizing the integration of advanced technologies such as cyber–physical systems, the Internet of Things, collaborative robotics, and explainable AI. While Industry 4.0 is marked by intelligent automation and digital connectivity, Industry 5.0 introduces a human-centric paradigm emphasizing sustainability, resilience, and co-creation. The findings underscore the significance of human–machine collaboration, process personalization, AI education, and ethical governance as foundational pillars of this new industrial era. This review highlights the emerging role of enabling technologies that reconcile technical performance with social and environmental values, promoting a more inclusive and sustainable model for industrial development.