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MILLMETER WAVE SOFTWARE DEFINED RADIO
No full textThis study presents the design, implementation, and evaluation of an advanced
SDR platform that significantly enhances flexibility, performance, and expandability
in wireless communication systems. The research encompasses the development
of a base SDR platform operating from 100 MHz to 6 GHz, complemented by
a mmWave expansion card extending the frequency range up to 40 GHz. The
platform’s architecture integrates a powerful signal processing core, featuring both
FPGA-based hardware processing and a quad-core ARM CPU, enabling efficient
handling of complex signal processing tasks.
Key features of the developed SDR platform include a wide frequency range, high
bandwidth capabilities of up to 56 MHz, and flexible sampling rates up to 60 MSPS
(with potential for 120 MSPS). The system incorporates MIMO 2x2 functionality and
an on-board frequency synthesizer operating up to 18 GHz, enhancing its versatility
for various wireless applications. The platform’s expandability is demonstrated
through the successful integration of the mmWave expansion card, showcasing
its readiness for next-generation wireless technologies, including 5G and beyond.
Additionally, the SDR’s modular design approach, coupled with multiple power
options, such as USB-PD and a high-speed PCIe interface for data offloading, ensures
adaptability to diverse research scenarios and future technological advancements.
Extensive laboratory and real-environment assessments validate the SDR plat form’s performance, confirming its compliance with and, in some instances, surpass ing initial design specifications. The research highlights the platform’s potential
for exploring new modulation schemes, investigating spectrum sharing techniques,
and developing novel wireless protocols. This work significantly contributes to the
field of software defined radio, providing a robust foundation for future research in
wireless communications, from IoT to fixed and cellular communications and radar
systems
Curae de Mim (Care for Me): A Personalized Alzheimer’s Care Nursing Intervention for Informal Caregivers
No full textArticle number - 270This article belongs to the Section Personalized Critical CareBackground: Informal caregivers of individuals with Alzheimer’s disease often experience high levels of emotional, physical, and psychological burden. Personalized nursing interventions are essential to support these caregivers and promote their well-being. Objectives: The objective of this study was to implement and evaluate a personalized psychoeducational intervention—Curae de Mim (Care for Me)—designed to reduce caregivers’ burden and enhance the emotional resilience among informal caregivers for people with Alzheimer’s disease. Methods: A mixed-methods study was conducted with 14 informal caregivers in a Portuguese community healthcare setting. The intervention consisted of six weekly group sessions guided by a mental health nurse, using cognitive–behavioral and recovery-oriented approaches. Results: After the intervention, the caregivers’ burden scores decreased significantly. The mean burden score dropped from 78 to 50. The thematic analysis revealed two key outcomes: emotional empowerment through peer interactions and reframing of the caregiver’s role through knowledge and self-care. Conclusions: This program proved effective in reducing caregivers’ burden and promoting adaptive coping. The integration of narrative reflection and specialized nursing care contributed to improved mental health outcomes
Prediabetes risk classification algorithm via carotid bodies and K-means clustering technique
No full textArticle number - e2516Diabetes is a disease that affects millions of people in the world and its early screening prevents serious health problems, also providing relief in the demand for healthcare services. In the search for methods to support early diagnosis, this article introduces a novel prediabetes risk classification algorithm (PRCA) for type-2 diabetes mellitus (T2DM), utilizing the chemosensitivity of carotid bodies (CB) and K-means clustering technique from the field of machine learning. Heart rate (HR) and respiratory rate (RR) data from eight volunteers with prediabetes and 25 without prediabetes were analyzed. Data were collected in basal conditions and after stimulation of the CBs by inhalation of 100% of oxygen and after ingestion of a standardized meal. During the analysis, a greater variability of groups was observed in people with prediabetes compared to the control group, particularly after inhalation of oxygen. The algorithm developed from these results showed an accuracy of 86% in classifying for prediabetes. This approach, centered on CB chemosensitivity deregulation in early disease stages, offers a nuanced detection method beyond conventional techniques. Moreover, the adaptable algorithm and clustering methodology hold promise as risk classifications for other diseases. Future endeavors aim to validate the algorithm through longitudinal studies tracking disease development among volunteers and expand the study’s scope to include a larger participant pool.This work was funded by Portuguese national funds provided by Fundação para a Ciência e Tecnologia: FCT-UIDB/05704/2020 and CEECINST/00051/2018 regarding Maria P. Guarino collaboration; and in the scope of the research project 2 ARTs—Acessing Autonomic Control in Cardiac Rehabilitation (PTDC/EMD-EMD/6588/2020) cof inanced by the Portuguese Foundation for Science and Technology (FCT). Rafael Pinheiro received financial support from the FCT through the Institutional Scientific Employment Stimulus CEECINST/00060/2021. The funders had no role in study design, data collection and analysis, decision to publish, or preparation of the manuscript
Elemental and Nutritional Characterisation with Vibrational Spectroscopy Analysis of Ulva sp., Gracilaria multipartita, and Sargassum muticum
No full textMacroalgae are rich in bioactive compounds with potential therapeutic appli cations, including antioxidant, antimicrobial, and nutritional properties. In this study,
the biochemical composition of three seaweed species—Ulva sp., Gracilaria multipartita,
and Sargassum muticum—was analysed, focusing on their mineral content and macronu trient profile. The ash, protein, fibre, lipid, and carbohydrate contents ranged from (dw)
26.56 to 33.53 g/100 g, 10.13 to 18.43 g/100 g, 0.11 to 0.19 g/100 g, 5.83 to 10.88 g/100 g,
and 42.48 to 53.27 g/100 g, respectively. The findings indicate that the species studied
are excellent sources of essential minerals, particularly magnesium, potassium, calcium,
sodium, and trace elements, such as iron, zinc, copper, and manganese. Sargassum muticum
exhibited the highest mineral content and thus holds significant promise for further ex ploration in biomedical and therapeutic contexts. FTIR, FT-RAMAN, and FT-NIR analysis
highlight the presence of proteins, lipids, carbohydrates, including cell wall phycocolloids,
and phenolic compounds. These results underscore the potential of macroalgae as natural
sources of bioactive compounds for health-related applications, highlighting their value
beyond traditional dietary supplementation.This work was funded by national funds through FCT, Fundação para a Ciência e a Tecnologia,
I.P., within the scope of the projects MARE, Centro de Ciências do Mar e do Ambiente, UID/04292/MARE,
ARNET, Aquatic Research Network, LA/P/0069/2020 (DOI:10.54499/LA/P/0069/2020), and CERNAS
UIDB/00681 (DOI:10.54499/UIDB/00681).N/
Definitions of determinants of physical activity behaviour: process and outcome of consensus from the DE-PASS expert group
No full textThe authors would like to acknowledge the significant contribution to this work of experts within Work Group 3 of the DE-PASS project. The authors would also like to thank Beverley Yohanan for her professional English language editing of this article.Article number - 34Background Despite extensive research on physical activity behaviour (PAB), consensus is lacking on related terms and definitions, thereby hindering the ability to compare findings between studies and to develop reliable assessment tools. This study therefore aimed to establish consensus on the definitions of key PAB determinants. Methods First, an international expert steering committee was established, comprising members of the European Cooperation in Science and Technology (COST) action “DEterminants of Physical ActivitieS in Settings” (DE‑PASS). Recently published review‑level studies were used to identify key determinants of PAB. Two independent reviewers systematically reviewed the literature to catalogue the range of definitions used for key determinants of PAB (steps 1–2). A two‑round modified Delphi survey was conducted online from February to September 2023, to determine the optimal definition for each determinant. In round 1, experts selected the most suitable definition for each of the 41 initially identified determinants. In round 2, experts ranked the appropriateness of the definition selected from round 1 on a 5‑point Likert scale. Consensus was defined a priori as ≥ 75% agreement on the definition (i.e., ratings of ≥ 4 points). A professional English language expert ensured concise, coherent wording and high‑quality editing of the definitions (steps 3–6). Results Eighty‑five experts in PAB research participated in round 1, and sixty‑nine experts in round 2. Consensus of definitions was achieved for 39 of the 41 determinants (88.4%–98.6% agreement). The consensus threshold was not achieved for two determinants: genetic profile and regulation (69.6%) and backyard access/size (73.9%). Conclusions The findings of this study offer a consensus‑based set of definitions for 39 key determinants of PAB. These definitions can be used homogenously in academic research on physical activity.This work was funded by the Virtual Mobilities and Short Time Scientific Missions grants of COST Action CA19101, titled 'Determinants of Physical Activities in Settings' (DE-PASS). JD was supported by the project “Research of Excellence on Digital Technologies and Wellbeing CZ.02.01.01/00/22_008/0004583” which is co-financed by Europe Union. JC acknowledges the support of the Center for Innovative Care and Health Technology (ciTechCare), funded by Portuguese national funds provided by Fundação para a Ciência e Tecnologia (UIDB/05704/2020). JCR acknowledges the support of the Research Center in Physical Activity, Health and Leisure (UID/DTP/00617/2020), and Laboratory for Integrative and Translational Research in Population Health (LA/P/0064/2020), funded by Portuguese national funds provided by Fundação para a Ciência e Tecnologia. Funding organizations had no role in study design, data collection and analysis, decision to publish, or preparation of the manuscript.The authors would like to acknowledge the significant contribution to this
work of experts within Work Group 3 of the DE-PASS project. The authors
would also like to thank Beverley Yohanan for her professional English lan‑
guage editing of this article
Novas vozes da página - entrevista a Cristiana Madureira
No full textA PÁGINA tem vindo a convidar e a integrar novos 69
colaboradores permanentes, pro ssionais da educação
e de outras áreas que vão partilhar com os leitores as
suas experiências e perspetivas. Nas próximas edições,
daremos a conhecer as novas caras, começando, nas
páginas seguintes, com Cristiana Pizarro Madureira e
Felipe Trillo Alonso.
Com uma vasta experiência como professora, com
carreira nacional e internacional, Cristiana Pizarro
Madureira é, desde janeiro de 2022, professora adjunta
na Escola Superior de Educação e Ciências Sociais, do
Instituto Politécnico de Leiria, onde coordena o curso
de Mestrado em Ciências da Educação: Educação e
Desenvolvimento Comunitário.
“Da minha experiência pessoal e pro ssional, aqui lo que mais gostaria de partilhar [com os leitores da
Novas vozes
na PÁGINA
UNIVERSIDADE SANTIAGO DE COMPOSTELA
PÁ GINA] prende-se com a necessidade de diariamente,
com fé e esperança, acreditarmos em todos e cada um
de nós e no poder que temos, como educadores, em
contribuir para a transformação daqueles com os quais
partilhamos a vida”, refere em entrevista.
Felipe Trillo Alonso cumpriu, em abril deste ano, 40
anos de exercício docente na Universidade de Santiago
de Compostela, na área da Didática e Organização Es colar. Durante esse tempo: aprendeu, ensinou, escreveu,
dirigiu e orientou – o que continua a fazer ainda hoje.
Aos leitores da PÁGINA pretende mostrar que “há
vida para além da subordinação ao burocratismo e ao
economicismo dominantes”, bem como da excelência,
da competitividade e da pressa, “que geram tanta in segurança e stress”, conta na entrevista.
Maria João Leiteinfo:eu-repo/semantics/publishedVersio
Potential of Marine Biomolecules: Advances in Extraction and Applications of Proteins, Polysaccharides, and Antioxidant Compounds
No full textOceans are increasingly viewed as a new frontier for economic development, contributing to the bridge between food industry, sea bioeconomy, and health. Nowadays, oceans are under attention as a strategy for creating opportunities and driving innovation, and their vital importance will become even more evident in the years to come. Therefore, it is crucial to study oceans under a holistic approach, taking the maximum value of their abundant resources in a sustainable way. As such, blue bioeconomy is the path forward, since it is a development strategy that meets the economic potential without compromising the environmental health. A special look needs to be taken at the underutilized resources and by-products, which hold unexploited value. For instance, green macroalgae are widespread marine macroalgae that lack industry applications, despite being rich in biopolymers (polysaccharides) and antioxidants. Moreover, fish by-products are also rich sources of biopolymers, mostly proteins. Thus, among other potential uses, raw materials could be explored to produce functional edible coatings under a blue bioeconomy approach. A detailed characterization of raw materials is the first step for the development of value-added products. These topics will be addressed in this review.This work was funded by national funds through FCT—Fundação para a Ciência e a Tecnologia, I.P.—via a PhD grant awarded to Gabriela Sousa (2022.13225.BD, https://doi.org/10.54499
/2022.13225.BD); project UIDB/04129/2020 of LEAF—Linking Landscape, Environment, Agriculture and Food Research Center (doi 10.54499/UIDB/04129/2020); MARE—Marine and Environmental Sciences Centre (UIDB/04292/2020); and ARNET—Aquatic Research Network (LA/P/0069/2020)
The impact of Covid-19 on Portuguese Accommodation Sector Default
No full textThe journal is institutionally owned by ISAG - European Business School, with the technical support of Research Center in Business Sciences and Tourism of the Consuelo Vieira da Costa Foundation (CICET-FCVC).Purpose: Worldwide travel restrictions and other measures to mitigate the pandemic situation caused a period of instability for accommodation companies. The consequences of this global phenomenon are still being explored. This study aims to understand the impact of Covid-19 on the probability of not fulfilling its obligations (default risk) and on its determinants in the Portuguese accommodation sector.
Methodology: A Logistic regression on a panel data of 8,688 companies located in Portugal, from 2017 to 2022 was used.
Results: The results show that Covid-19 contributed to an increase in the percentage of defaulters. Moreover, the pandemic situation had an impact on what determines financial difficulties. The determinants are different depending on the period analyzed, and the company’s size.
Originality: This study adds empirical evidence on the impact of non-payment in the accommodation sector in Portugal and, to the best of our knowledge, there is a lack of literature on the impact of Covid-19.This research was supported by National Funds of the FCT – Portuguese Foundation for Science and Technology within the project [UIDB/04928/2020]
A importância do projeto “Gerações em 2 Pautas” e a sua valorização no possível decréscimo da solidão dos idosos residentes nos lares
No full textEste projeto incide sobre a problemática da solidão dos idosos institucionalizados em lares. Foca-se, especialmente, na compreensão dos contributos de programas de intervenção assentes no uso de estratégias promotoras de experiências artísticas e culturais na redução da solidão nesta população. Assim, tendo em conta a natureza do projeto “Gerações em 2 Pautas”, procurou-se compreender os seus contributos na redução da solidão dos idosos residentes nos lares, nomeadamente institucionalizados do Centro Social Paroquial da Caranguejeira, Lar São Cristóvão e do Centro Paroquial de Santa Catarina da Serra.
Através da análise do projeto, de pesquisa documental, do resultado da análise de entrevistas semiestruturadas individuais e em pequenos grupos junto dos agentes envolvidos nas instituições participantes , traçam-se os âmbitos de ação do projeto “Gerações em 2 Pautas”; procura-se perceber como foi percecionado pelos seus participantes, compreender a importância do recurso a estratégias do domínio das artes e da cultura na diminuição da solidão nos idosos institucionalizados, entender a importância desses processos de partilha de experiências e vivências de aprendizagem entre diferentes gerações.
Na perspetiva dos entrevistados, este projeto contribuiu para a redução da diminuição dos idosos institucionalizados através das oportunidades proporcionadas para a sua valorização enquanto ser individual e coletivo. Os resultados sugerem, ainda, o contributo destas vivências artísticas e culturais para a sensação de maior inclusão dos idosos institucionalizados na sociedade, maior respeito e valorização das suas vozes, que ficaram mais ativas através das partilhas das suas histórias e vivências.
Assim, as experiências artísticas e culturais proporcionadas pelo projeto desempenharam um papel performativo, mediador, inclusivo, capaz de esbater barreiras sociais, (re)criando, deste modo, laços e novas experiências através de aprendizagens, partilhas e dinâmicas criativas
“É estar a ver a nossa casa a arder e atirar gasolina para o fogo”: poder, resistência e luta em defesa do planeta.
No full textinfo:eu-repo/semantics/publishedVersio