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Accelerated dynamic light sheet microscopy: unifying time-varying patterned illumination and low-rank and sparsity constrained reconstruction
No full textLight Sheet Fluorescence Microscopy (LSFM) enables rapid and gentle 3D fluorescence imaging of dynamic processes over extended periods in translucent samples at the mesoscopic scale. However, its temporal resolution is constrained by the sequential acquisition of individual two-dimensional planes at varying depths, making it challenging to capture rapid dynamics such as the beating of a zebrafish heart. To address this limitation, we recently developed spatially modulated Selective Volume Illumination Microscopy, which utilizes a compressed sensing approach to reconstruct the entire imaging volume from measurements where multiple planes are illuminated simultaneously using spatially modulated light. Building on this advancement, we now introduce a novel spatio-temporal patterned illumination strategy and volume reconstruction method that incorporates low-rank and sparsity constraints, effectively leveraging the temporal and spatial redundancy present in sequential volumetric acquisitions. This method was applied to the volumetric imaging of embryonic zebrafish hearts, achieving an improvement in imaging speed of 4-fold compared to standard LSFM and a 2-fold improvement compared to traditional compressed sensing approaches, while preserving reconstruction accuracy and enabling the visualization of fast dynamic events with a resolution of a few tens of milliseconds. Our approach represents a step forward in enhancing the temporal resolution of LSFM for studying fast biological dynamics.LCF/PR/HR22/00533; 871124; 101094250; IR0000016; CUP B53C2200175000
Development of an untouchable interactivity system for the live cinema performance: SSL2020
No full textO presente artigo relata o processo de criação de um sistema de interatividade intocável para a performance de live cinema SSL2020. Esse sistema possibilita a performer de interagir ao vivo com os elementos áudio e visuais da obra, assim como de manipular a narrativa do filme, através dos movimentos corporais. Utilizou-se um periférico computacional que deteta os gestos das mãos, um software de programação visual para a criação do projeto, e uma interface intermédia que atua como um controlador digital. O conjunto destas tecnologias forma um sistema que não necessita de toque direto nos objetos para funcionar durante a performance.info:eu-repo/semantics/publishedVersio
Social media as a driver of physical activity: a snapshot from sport sciences students
No full textSocial media has become integral to daily life. During the COVID-19 pandemic, these digital tools enabled people to maintain physical activity at home despite restrictions, positively impacting public health. This study examines whether the trend of using social media to support physical activity has continued post-pandemic. A questionnaire was administered to 251 university sport sciences students to gauge their perceptions of social media's role in guiding and promoting physical activity. The findings indicate that participants engage with social media daily, viewing platforms such as YouTube, Instagram, and TikTok as valuable for visualizing and promoting physical activity. However, they report a lack of professional training in social media use at the university level. These results carry practical implications for health policymakers, educational institutions, faculty, students, and sport industry professionals, highlighting the importance of targeted training in social media management and the development of relevant policies to harness the potential of social media in promoting physical activity
Editorial on the themed issue in honor of Carlos Gutiérrez Merino: forty years of research excellence in the field of membrane proteins and bioenergetics
No full textProf. Carlos Gutiérrez-Merino has led over 30 research projects funded by national and international agencies and, under his guidance, numerous researchers have developed their doctoral theses, contributing to the growth of biomedical research in Extremadura
A high-resolution chronology for the archaeological deposits at Pinnacle Point 5–6, Western Cape Province, South Africa
No full textPinnacle Point Site 5-6 (PP5-6) is a key archaeological and paleoenvironmental site located on the edge of the Palaeo-Agulhas Plain along the southern Cape coast of South Africa. Construction of high-resolution chronologies for archaeological sites beyond the range of radiocarbon dating is challenging. Geochronological methods such as optical dating are hampered by the availability of applicable materials that are directly associated with the events of interest. Optical dating relies on assumptions made about time-dependent changes and is made up of a series of measurements each with its own random and systematic uncertainties that together make up the age estimates. In this study, we explicitly took on the challenge to systematically produce a high-resolution chronology for PP5-6 made up of 197 individual age estimates of which 169 were input into a Bayesian age model. PP5-6 is ideal because of its fine-scale stratigraphy and use of modern excavation techniques and detailed recording of stratigraphy and plotted finds. Excavations and dating took place concurrently over almost two decades to inform the dating strategy, contextualise sample choice and data analysis, and to bring the scales of analysis of different proxies closer together. Here we present the optical dating process, including sensitivity tests of our instruments, data analysis procedures and modelling approach. We then construct a final timeline for comparisons with other proxy data and interpretation of the sedimentary sequence and occupation of PP5-6 over an interval of similar to 60,000 years from similar to 110,000 to similar to 50,000 years ago. We show how closely linked sediment deposition is to changes in global climate and sea-level, identify a few Pleistocene and Holocene erosional events that modified the site post-depositionally and place a variety of interconnected causes and effects coincident with different types of occupation on this timeline. This approach opens up opportunities to reduce the resolution of chronologies closer to the human timescales required to improve our understanding of changes through time and to make more direct comparisons between other sites and proxies that contain similarly highly resolved archives of human occupation and change.BCS-0524087; BCS-1138073; BCS-146037
Revisiting the thermal alteration of buried bone
No full textThe impacts of heat exposure directly on bone material are widely acknowledged, yet a comprehensive understanding regarding the degree of thermal alteration experienced by bone buried beneath a combustion feature or fire event remains poorly described. Such potential incidental burning below a surface fire presents challenges for distinguishing between the intentional remains of fire use behaviors from haphazard heat exposure. In this study, we address the extent to which buried bone material can undergo alteration under concentrated high-heat conditions, achieved through using a fire simulator operating at 950 degrees C for a duration of 6 h simulating a high temperature hearth fire. Here we describe the degree of carbonization and calcination in bone samples buried at three depths (-2,-6, and-10 cm) in gravel and a mixed gravel and fine sand substrate. We find that, at the sustained temperature of 950 degrees C, plus heating and cooling time, calcination of bone material can occur at shallow depths of-2 cm under the fire simulator, whereas at-6 cm only one sample of each experimental condition is recognized to be fully structurally and chemically calcined. Despite only two samples calcining at this depth, several other bones buried at-6 cm displayed pale and light coloration, experiencing the elimination of organics without undergoing true calcination, likely due to the prolonged exposure to heat removing the organic component. At-10 cm depth, bone material centered under the heat source became carbonized, while buried bones positioned at the periphery of the heat source are recognized only be partially thermally altered. Notably, neither gravel nor a mixture of gravel and sand substrates create a detectable reduction environment in the spectroscopic analyses of the buried bones. Our findings highlight that not only can post-depositional heating significantly impact buried faunal material, but that in this way humans can act as post-depositional agents
Seasonal variation in seabird abundance and bycatch at artisanal bottom-set net fisheries in the southern Iberian Atlantic coast
No full textBycatch is a major cause of seabird mortality, yet most studies focus on industrial fisheries, with limited knowledge on artisanal fisheries. This study investigates the seasonal abundance of seabirds off the southern-eastern coast of mainland Portugal, their attendance at artisanal bottom-set net fisheries, and observed bycatch, using onboard observations and fishermen interviews. From March 2020 to November 2022, 24,643 seabirds were observed attending fishing vessels in 183 daily fishing trips (98.4 % of 186 trips), spanning 20 species across 7 families, with 25 seabirds recorded as bycatch. Lesser black-backed and Yellow-legged gulls (Larus fuscus and Larus michahellis) were the most abundant species, followed by Audouin's gulls (Ichthyaetus audouinii), Great shearwaters (Ardenna gravis), and Northern gannets (Morus bassanus). During summer, the abundance of Yellow-legged and Audouin's gulls (local breeders) and Lesser black-backed gulls (non-breeding species) increased with fishery catch per unit effort. Great shearwaters were more affected by gear type, exhibiting higher attendance and bycatch in trammel nets during autumn. 65 % of Great shearwater bycatch occurred during a single fishing event, probably from fishermen cleaning nets and discarding fish and viscera during net setting. Fishermen interviews identified Northern gannets and Great cormorants (Phalacrocorax carbo) as the most frequently bycaught species, particularly in winter when onboard observations were limited. These findings underscore the impact of artisanal fisheries on seabird populations and highlight the importance of combining onboard data with fishermen interviews to improve bycatch estimates and inform conservation efforts. Our study also suggests that fishermen behaviour during fishery operations significantly influence seabird bycatch.LIFE18 NAT/PT/000927; 2022.07032.CEECIND/CP1714/CT0009; 2021.01812.CEECIND/CP1656/CT001
Distinct shoreline behaviour along storm‐dominated and geologically controlled coastal barriers
No full textContemporary shoreline change is driven by a complex combination of factors, and as such is often highly variable along the coast. While differences in beach morphology can explain some of the variability in shoreline change, the geological constraints imposed by coastal geology are often overlooked. This work examines the influence of foreshore configurations with varying degrees of non-dynamic geological control, which are analysed in combination with hydrodynamic forcing to investigate seasonal to multiannual shoreline evolution along five coastal barriers in the Outer Hebrides, Western Scotland. These barriers are characterised by strongly geologically constrained evolution and are exposed to a storm-dominated wave climate. Due to the variable temporal interval between available cloud-free Planet Scope images, monthly averaged vegetation lines from 2016 to 2023 were derived from satellite imagery as a shoreline position indicator using an automated approach validated by visual inspection. The satellite-derived vegetation lines have a sub-pixel accuracy with a root mean square error of 3 m. Changes in monthly averaged shoreline position are statistically correlated with monthly extreme storm conditions, characterised by both extreme water levels and wave conditions. However, the control exerted by the variable geological configuration along the barriers results in distinct inter- and intra-site shoreline change behaviour, with lower shoreline variability observed in barrier sectors fronted by rocky foreshores, compared to sediment-rich foreshores. The observed multiannual shoreline change from 2016 to 2023 is characterised by a small but statistically significant accreting trend (mean 0.4 m/yr), likely representing the recovery of the barriers from extreme winter storms that impacted northern European coasts from 2013 to 2015. The results demonstrate that considering variable geological controls in shoreline change assessments improves the understanding of shoreline variability along coastal barriers, allowing to identify distinct storm-driven shoreline behaviour according to the degree of geological control.UID/0350/2020; CEECINST/00052/2021/CP2792/CT0011; BSG-2022-3
Proceedings of Education International Congress/Multiplier Event RESUPERES "Resilience in Higher Education"
No full textThis publication is a part of the Overcoming adversities. Resilience in the Higher Education, Project (RESUPERES), an Erasmus+Cooperation partnership in higher education KA220-HED, project funded by the European Commission for the period 2022-2025. Coordination of the University of Granada. Erasmus Key Action 2: 2021-1- ES01-KA220-HED-000031173Project (RESUPERES), an Erasmus+Cooperation partnership in higher education KA220-HED, project funded by the European Commission for the period 2022-2025. Coordination of the University of Granada. Erasmus Key Action 2: 2021-1- ES01-KA220-HED-00003117
Novel field experiment on alkalinity enhancement in intertidal environments—a trailblazer for natural climate solutions
No full textOne recently proposed approach to reduce atmospheric CO2 concentrations is marine alkalinity enhancement. This technique increases the CO2 uptake capacity of seawater through weathering of fine-grained (mafic) rocks and minerals in marine environments. The weathering process has been extensively tested in laboratory studies and verified by numerical models. Field experiments scaling the CO2 uptake under natural conditions are still lacking. In a methodological approach, a novel in situ experiment was designed and installed in a salt marsh at Ria Formosa coastal lagoon, southern Portugal. The experiment comprised deployments of different sizes of olivine and basalt substrates, and a control site, which were tidally submerged twice a day. A monthly monitoring scheme of supernatant and porewater properties from each deployment and control site was established, and procedures for temperature, salinity, oxygen, pH, total alkalinity, nutrient, and trace metal analyses were defined. This paper is devoted to the methods and describes the design, a protocol for the analyses, and an evaluation of experimental performance and reliability. Data from the first 6 months are presented for validation of the experiment. They demonstrated elevated total alkalinity in water samples, mostly in porewater after the deployments, while salinity, oxygen, and pH reflect the control conditions. Significant alkalinity differences were observed between the treatments and the natural background conditions monitored at the control site, during the 6 months of the experiment. The methodological approach is presented with strengths, limitations, and recommendations for an upscaling as CO2 removal measure, servicing, and subsequent investigations.PTDC/CTA-CLI/1065/2021; CEECINST/00052/2021/CP2792/CT0012; CEECINST/00052/2021/CP2792/CT0007; CEECINST/00146/2018/CP1493/CT0002; S-026426/202