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Reviews and syntheses: review of proxies for low-oxygen paleoceanographic reconstructions
Publication . Hoogakker, Babette A.A.; Davis, Catherine; Wang, Yi; Kusch, Stephanie; Nilsson-Kerr, Katrina; Hardisty, Dalton S.; Jacobel, Allison; Macaya, Dharma Reyes; Glock, Nicolaas; Ni, Sha; Sepúlveda, Julio; Ren, Abby; Auderset, Alexandra; Hess, Anya V.; Meissner, Katrin J.; Cardich, Jorge; Anderson, Robert; Barras, Christine; Basak, Chandranath; Bradbury, Harold J.; Brinkmann, Inda; Castillo, Alexis; Cook, Madelyn; Costa, Kassandra; Choquel, Constance; Diz, Paula; Donnenfield, Jonas; Elling, Felix J.; Erdem, Zeynep; Filipsson, Helena L.; Garrido, Sebastián; Gottschalk, Julia; Menon, Anjaly Govindankutty; Groeneveld, Jeroen; Hallmann, Christian; Hendy, Ingrid; Hennekam, Rick; Lu, Wanyi; Lynch-Stieglitz, Jean; Matos, Lélia; Martínez-García, Alfredo; Silveira Molina, Giulia; Muñoz, Práxedes; Moretti, Simone; Morford, Jennifer; Nuber, Sophie; Radionovskaya, Svetlana; Raven, Morgan Reed; Somes, Christopher J.; Studer, Anja S.; Tachikawa, Kazuyo; Tapia, Raúl; Tetard, Martin; Vollmer, Tyler; Wang, Xingchen; Wu, Shuzhuang; Zhang, Yan; Zheng, Xin-Yuan; Zhou, Yuxin
A growing body of observations has revealed rapid changes in both the total inventory and the distribution of marine oxygen over the latter half of the 20th century, leading to increased interest in extending oxygenation records into the past. The use of paleo-oxygen proxies has the potential to extend the spatial and temporal range of current records, constrain pre-anthropogenic baselines, provide datasets necessary to test climate models under different boundary conditions, and ultimately understand how ocean oxygenation responds beyond decadal-scale changes. This review seeks to summarize the current state of knowledge about proxies for reconstructing Cenozoic marine oxygen: sedimentary features, sedimentary redox-sensitive trace elements and isotopes, biomarkers, nitrogen isotopes, foraminiferal trace elements, foraminiferal assemblages, foraminiferal morphometrics, and benthic foraminiferal carbon isotope gradients. Taking stock of each proxy reveals some common limitations as the majority of proxies functions best at low-oxygen concentrations, and many reflect multiple environmental drivers. We also highlight recent breakthroughs in geochemistry and proxy approaches to constraining pelagic (in addition to benthic) oxygenation that are rapidly advancing the field. In light of both the emergence of new proxies and the persistent multiple driver problem, the need for multi-proxy approaches and data storage and sharing that adhere to the principles of findability, accessibility, interoperability, and reusability (FAIR) is emphasized. Continued refinements of proxy approaches and both proxy–proxy and proxy–model comparisons are likely to support the growing needs of both oceanographers and paleoceanographers interested in paleooxygenation records.
Understanding risk factors of post-stroke mortality
Publication . Castro, David; Antonio, Nuno; Marreiros, Ana; Nzwalo, Hipólito
Stroke is one of the leading causes of death worldwide. Understanding the risk factors for poststroke mortality is crucial for improving patient outcomes. This study analyzes and predicts poststroke mortality using the modified Rankin Scale (mRS), a functional neurological evaluation scale. Several Machine Learning models were developed and assessed using a dataset of 332 stroke patients from Hospital de Faro, Portugal, from 2016 to 2018. The Random Forest model outperformed others, achieving an accuracy of 98.5% and a recall of 91.3. Twenty-four risk factors were identified, with stroke severity as the most critical. These findings provide healthcare professionals with valuable tools for early identification and intervention for high-risk stroke patients, enabling informed decision-making and customized treatment plans. This research advances healthcare predictive analytics, offering a precise mortality prediction model and a comprehensive analysis of risk factors, potentially improving clinical outcomes and reducing mortality rates. Future applications could extend to patient monitoring and management across various medical conditions.
How reliable is the evaluation of DNA binding constants? insights and best practices based on an inter-laboratory fluorescence titration study
Publication . Dömötör, Orsolya; Binacchi, Francesca; Ribeiro, Nádia; Busto, Natalia; Gonzalez-García, Jorge; Garcia-España, Enrique; Correia, Isabel; Enyedy, Éva A.; Hamacek, Josef; Terenzi, Alessio; Basílio, Nuno; Barone, Giampaolo; PALMA ANTUNES CAVACO, ISABEL MARIA; Biver, Tarita
In all experimental sciences, the precision and reliability of quantitative measurements are paramount. This is particularly true when examining the interactions between small molecules and biomolecules/polyelectrolytes, such as DNAs/RNAs, and yet it is overlooked in most publications of thermodynamic binding parameters. This paper presents findings from COST Action 18202 “Network for Equilibria and Chemical Thermodynamics Advanced Research,” which assessed the consistency of data derived from the interactions of calf-thymus DNA (CT-DNA) with the fluorescent intercalator ethidium bromide (EB) through spectrofluorimetric titrations. We first discuss critical experimental aspects and propose a reference experimental protocol which can be used to calibrate procedures for the determination of nucleic acid binding equilibrium constants. We then fit the experimental points according to different procedures and analyse the results focusing on the statistical dispersion of the data, aiming at enlightening the strong and weak points of different fitting procedures. The implications of this work are significant, demonstrating how the statistical dispersion of experimental data can influence the interpretation of biochemical coordination mechanisms. Our study reveals that, despite rigorous protocol standardization, the determination of binding parameters remains sensitive to the choice of data fitting method, with deviations in the logarithmic stability constant (logK) values not falling below 5 % relative standard deviation (RSD), or ± 0.5 logK units for 95 % confidence. This variability evidences the critical need for standardized best practices in data treatment as well as experimental procedures. Although our study focuses on the EB/CT-DNA system through fluorescence titrations, the broader implications for other methodologies across various biochemical systems highlight the importance of this first-of-its-kind inter-laboratory comparison in advancing our understanding of biochemical coordination processes.
Physics with non-unital algebras? an invitation to the okubo algebra
Publication . Marrani, Alessio; Corradetti, Daniele; Zucconi, Francesco
This paper presents some preliminary discussion on the possible relevance of the Okubonions, i.e. the real Okubo algebra O, in quantum chromodynamics (QCD). The Okubo algebra lacks a unit element and sits in the adjoint representation of its automorphism group SUO, thus being fundamentally different from the better-known octonions O. While these latter may represent quarks (and color singlets), the Okubonions are conjectured to represent the gluons, i.e. the gauge bosons of the QCD SU(3) color symmetry. However, it is shown that the SU(3) groups pertaining to Okubonions and octonions are distinct and inequivalent subgroups of Spin(8) that share no common SU(2) subgroup. The unusual properties of Okubonions may be related to peculiar QCD phenomena like asymptotic freedom and color confinement, though the actual mechanisms remain to be investigated.
Exploração das percepções sobre o emprego na hotelaria no Algarve durante a COVID
Publication . Castela, Guilherme; Henriques, Cláudia Helena; Lampreia Carvalho, Fatima; Afonso, Carlos
The Travel and Tourism (T&T) industry is highly sensitive to extreme events like pandemics (Price et al., 2022; OECD, 2020). The COVID-19 pandemic severely disrupted the sector, leading to mobility restrictions and closures (Chowdhury and Jomo, 2020). However, it also presented opportunities for innovation (Price et al., 2022). The economic impact on Portugal's GDP was significant, with T&T's contribution dropping from 17.1% in 2019 to 8.7% in 2020 and recovering in subsequent years (WTTC, 2022). Given the Algarve's dependence on tourism, this study highlights the need for new strategies to overcome challenges (EURES, 2022). This research aims to analyse how Algarve's (South of Portugal) hospitality (hotels and restaurants) employers and employees perceived the Portuguese government's measures to address the COVID-19 crisis via a Three-Way Data Analysis multivariate statistical procedure, namely the COSTATIS method, which can be considered a more advanced or specialized version of STATIS, offering more flexibility and refinement in handling complex data relationships. The statistical procedure supports the assessment of 27 varieties of perceptions of the pandemic crisis that were collected from respondents distributed in four hospitality professional categories (restaurant and hotel managers and employees). The conclusions identify that association with a professional category in the hospitality industry tends to affect ideas regarding the potential for coping and resilience associated with organizational challenges. Members of the diverse professional categories think of the crisis in different ways due to their status and hierarchic position in business organisations. More attention should be given to what those professionals with lower status have to say about the organisational climate in the event of future crises.