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Effect of petrochemical contaminants on the photosynthetic physiology on the seagrass Halophila baillonii Ascherson
No full textOil spills represent a significant threat to seagrasses as hydrocarbons can impair photosynthetic processes and plant functioning, although physiological responses may vary depending on the spill and environmental conditions This study investigates the physiological responses of Halophila baillonii when exposed to the watersoluble fraction (WSF) of crude oil. Photosynthetic pigment composition, maximum quantum yield (Fv/Fm), and oxidative stress indicators malondialdehyde (MDA) and hydrogen peroxide (H2O2) were analyzed after shortterm exposure. A significant increase in chlorophyll a and b concentrations and variations in carotenoid levels were detected, while photochemical efficiency and oxidative stress indicators were maintained. These findings suggest that the species dynamically adjusts its pigment composition to optimize light capture and mitigate oxidative stress, demonstrating physiological plasticity. Its ability to tolerate WSF exposure highlights the species' short-term resilience to hydrocarbon pollution. Future studies should investigate the effects of long-term exposure to different oil types, such as boat fuel, and the recovery mechanisms of seagrasses.grant number 88887.497010/2020–00 and BFP-0204-2.05/25; grant number 440826/2020–
P0463 Distinct hepcidin dynamics in crohn’s disease and ulcerative colitis: links to iron homeostasis and inflammatory activity
No full textBackground: Hepcidin, the master regulator of systemic iron metabolism, is influenced by iron availability and inflammation.1 In inflammatory bowel disease (IBD), iron deficiency and anaemia are common, yet how hepcidin is regulated in relation to disease phenotype, iron status and inflammatory burden remains incompletely understood.2 We aimed to characterise hepcidin regulation in ulcerative colitis (UC) and Crohn’s disease (CD) according to iron status and inflammatory markers. Methods: In this cross-sectional multicentre study, 589 individuals were enrolled (178 healthy controls, 130 UC, 281CD). Patients were stratified by iron status and activity. Serum hepcidin, iron parameters, and inflammatory and clinical data were collected. Iron deficiency was defined using the ECCO criteria2 , which focuses on ferritin, and a combined ferritin and transferrin saturation definition. Group comparisons, correlations, and multivariable linear regressions were performed. Results: Hepcidin correlated positively with C-reactive protein (CRP) in CD (r=0.125; p=0.038) and negatively with faecal calprotectin (FCAL) in UC (r=-0.311; p
Thermal performance experimental study of a robust funnel solar cooker using an enhanced evaluation method
No full textThe Pucca solar cooker is a domestic funnel-type cooker, constructed of concrete and silvered glass mirrors. Its robust construction allows it to be kept outside permanently, in all weather conditions. However, its reflectors may gradually degrade over time, leading to diminished performance. To assess this issue, six Pucca cookers were tested side by side using a water load of 2 kg in each cooker. Two of the cookers had new mirrors, two had minimally degraded mirrors, and two had badly degraded mirrors. Non-linear efficiency curves were determined by a suitable enhanced evaluation method. Small differences were noted between the efficiency curves of the four cookers with the least degraded reflectors. By contrast, the points of maximum efficiency for the two cookers with badly degraded reflectors amounted to only about 70% of the value seen in the other cookers. The impact of this degradation on performance is illustrated by the figures predicted using the enhanced procedure, where the measured temperature data were fitted to a second-order polynomial with a time-dependent exponential term to derive nonlinear efficiency curves. The best performing cooker is expected to boil 2 kg of water in about three hours when the ambient temperature is 20 ◦C and the solar irradiance is 700 Wm 2, and in only 1.4 h when the ambient temperature is 30 ◦C and solar irradiance is 1000 Wm 2. The two cookers with badly degraded mirrors could not boil 2 kg of water at all under either of those conditions. The enhanced method is reliable
P0397 Soluble transferrin receptor as a reliable inflammation-independent marker of iron deficiency in crohn’s disease and ulcerative colitis
No full textBackground: Iron deficiency is a common complication in inflammatory bowel disease (IBD), including ulcerative colitis (UC) and Crohn’s disease (CD).1 However, standard iron markers are influenced by inflammation, complicating the diagnosis of true iron deficiency.1,2 Soluble transferrin receptor (sTfR) has been proposed as a more reliable, inflammation-independent marker of iron demand.3 This study aimed to assess the utility of sTfR in identifying iron deficiency without anaemia (IDWA). Methods: The ID_IBD study was a multicentre, cross-sectional study. Iron status was classified using two approaches: the ECCO consensus definition, focusing on ferritin thresholds adjusted for inflammatory markers (C-reactive protein [CRP] and faecal calprotectin [FCAL]), and a stricter definition that adds transferrin saturation to the ECCO criteria. sTfR levels were compared across groups, and ROC curve analysis was used to identify optimal diagnostic cut-offs. Results: This analysis included 411 IBD patients (130 UC, 281CD) and 178 controls. sTfR showed no correlation with CRP or FCAL. In UC, patients with IDWA had significantly higher sTfR levels (median 1.20mg/L, IQR 1.02-1.42) compared to non-IDWA patients (median 1.05mg/L, IQR 0.92-1.22; p=0.013). Anaemic UC patients also showed elevated sTfR levels (median 1.27mg/L, IQR 1.14-1.59) compared to non-IDWA individuals (patients but was significantly higher in anaemic patients (p=0.003). Conclusion: sTfR appears to be an inflammation-independent marker of iron status in IBD. It showed potential for identifying IDWA in UC, while in CD it mainly reflected increased iron demand in anaemia. Further longitudinal studies are warranted to validate its role and assess its clinical utility in IBD
Can sudden fluctuations in tourism demand influence the earnings management practices of the hotel industry? Evidence from Portugal
No full textThis study examines how sudden shifts in tourism demand affect the Earnings Management (EM) strategies of hotel firms, using Portuguese companies as the study context. This paper uses accounting data from 490 non-listed Portuguese hotel firms collected from the ORBIS database over the 2016-2021 period. The presence of EM practices is investigated using the methodology developed by Burgstahler and Dichev (1997), while panel data regression is used to explore the impact of the COVID-19 pandemic on the sample firms' EM practices. Portuguese hotel firms use EM practices upward or downward depending on their starting position. In general, these firms tend to manipulate results in order to avoid reporting losses, a practice they intensify when faced with a sharp decline in demand. In particular, this paper finds that, during the recent pandemic period, such companies have aggressively used the discretionary component of accruals to disclose higher results. To the best of our knowledge, this is the first article exploring how a sudden decline in tourism demand affects the EM behaviour of firms operating in the hospitality sector. Our findings have important implications for such companies' stakeholders, especially investors and regulators.UID/ ECO/04007/2020, UI/BD/150797/202
MARS lander: georeferencing landing and pop points of untethered ocean monitoring systems using fundamental physics
No full textSubsurface observations are crucial for understanding the ocean's role in Earth's climate and for refining climate models. However, existing aquatic monitoring systems that allow such insights remain complex and costly due to their high demands for deployment, sampling, and recapture. Since low-cost, easy-to-deploy deep-sea landers are scarce, and with the aim of facilitating more subsurface observations, this study provides a simple method for georeferencing small-sized untethered landers. Their underwater trajectories are modelled with fundamental physics, dead reckoning, lander geometry, and numerical simulations. Using free fall, upthrust, and ocean current dynamics, the proposed approach estimates their underwater trajectories, including landing (at the seabed) and pop (at the sea surface) points. The method relies on the lander's physical characteristics, including its vertical and horizontal cross-sectional areas, to calculate the drag force coefficients used to determine its trajectories during descent and ascent through the water column. Ocean currents' magnitudes are modelled using Ekman's exponential decay down to 90 m of the water column, while the depths until 900 m are modelled from prior ADCP surveys by varying ocean current headings with depth between − 20 and 20◦. Surface ocean and wind current headings are modelled with open datasets from satellite telemetry. Lander's velocity, displacement, and dive time to the landing and pop points, including the total radial excursion and uncertainty in heading, are analytically derived, numerically calculated, and empirically assessed a-posteriori until 90 m, yielding a ~38 m radial excursion (40% error) against the obtained GNSS coordinates in field deployment, and 33◦ in heading uncertainty during a 138-s excursion. Additional random walk simulations are shown for full ocean depth obtaining radial excursion of 1038 m with 278 min total dive time. This approach is generalizable to any subsurface aquatic monitoring systems targeting deployments with diverse payloads from smaller sea vessels, not requiring cranes, radio, GNSS, or acoustic telemetry. Since it accounts for key nature factors, our method provides special benefits in planning and optimizing deployments. Additional discussion focuses on the method's practicality for full ocean depth deployments.PTDC/CCI-COM/0450/2020; CEECINST/00098/201
Mapping saltmarsh vertical distribution communities in southern Portugal using high spatiotemporal resolution satellite imagery
No full textSaltmarshes, transitional coastal habitats between terrestrial and marine ecosystems, offer crucial ecological benefits, including coastal protection, biodiversity enhancement, water purification and carbon sequestration. However, saltmarsh areas are shrinking, primarily due to human activities. Traditional monitoring approaches for saltmarsh coverage are often costly and restricted in spatial scope, prompting a shift towards remote sensing techniques. While remote sensing has proven effective for studies that cover large spatial areas, its application for smaller areas remains challenging. In this study, we trained classification models to identify saltmarsh vegetation communities in southern Portugal. We utilized high-resolution (3-metre) and high-frequency (near-daily) imagery to optimize image selection according to tidal conditions at the time of capture and developed an elevation proxy for the intertidal zone. Our model achieved an overall accuracy of 67%, estimating a total of 4,572 ha of saltmarsh in southern Portugal, 85% located in the Ria Formosa lagoon. The middle saltmarsh zone, dominated by Atriplex portulacoides, Salicornia perennis and Salicornia fruticosa, covered the largest area. The approach presented here holds promise for further refinement, enabling automated, high-resolution monitoring of saltmarsh communities, which is essential for conservation and management initiatives.020.03825.CEECIND; A.BG.CALL4.012.2020; Grants FAM 2023/2024N/
Older men´s perceptions on nonformal and formal activities in the community
No full textThe demographic landscape of Europe is undergoing a profound transformation, with a growing proportion of older adults. In response, European Commission has adopted the Active Ageing policy, aligning with the World Health Organization’s framework, to promote participation among older adults. However, participation in learning activities remains unevenly distributed, often favouring those with higher educational attainment and women. Drawing on Cumulative Advantage and Disadvantage theory, the main aim of this study is to understand if differences and similarities in older men’s perceptions of non-formal and informal activities are shaped by their educational attainment. Using a biographical research approach, we analysed narrative interviews with 54 older men from southern Portugal, alongside with three focus groups with educators and non-formal education providers. Our findings revealed that social class and gender are key factors in influencing older adults’ participation in learning and community activities. Older men with lower educational attainment faced precarious work conditions, financial instability, and limited engagement in learning activities. In contrast, those with higher educational attainment benefited from cultural engagement and social capital, being more involved in learning activities. Gender also influenced community participation, with older women favouring structured learning and older men favouring informal, community-based activities. Community activities seem to be a way for women to leave traditional domestic spaces and to express changes in their daily lives. The lower participation of men in such activities can be explained by social class, but also by the gendered nature of different spaces. Men tend to seek out safe, predominantly male spaces and avoid mixed education and learning spaces. Both situations stem from patriarchal dominance in private relations and a more nuanced relative dominance in community/societal relations.info:eu-repo/semantics/draf
Phytochemical composition and bioactivity of different fruit parts of opuntia robusta and opuntia ficus-indica: conventional versus NADES-based extraction
No full textThis study evaluated the extraction efficiency of two Natural Deep Eutectic Solvents (NADESs), glycerol–urea (1:1) and citric acid–sorbitol (1:2), for recovering phenolic compounds from the different parts of the fruit (pulp, seed-containing pulp, seeds, and peel) of Opuntia robusta and Opuntia ficus-indica in comparison with 50% methanol. Phytochemical profiling was performed using ultra-high-performance liquid chromatography–highresolution mass spectrometry, alongside antioxidant and enzyme inhibition assessments (acetylcholinesterase, butyrylcholinesterase, tyrosinase, α-glucosidase, and α-amylase). Glycerol–urea performed similarly to methanol in extracting phenolic compounds with notable antioxidant properties. Peel extracts contained the highest levels of bioactive compounds, particularly phenolic acids (525.49 in O. robusta and 362.96 µg/gDW in O. ficus indica). Enzyme inhibition varied across species and fruit parts, with extracts from both species inhibiting all targeted enzymes. Notably, this study provides the first evidence of tyrosinase inhibitory activity in O. robusta, which exhibited the strongest inhibition. Overall, these results emphasize the potential of cactus fruit extracts, particularly from O. robusta, for valorization, and support the use of NADESs as a sustainable and medium for extracting antioxidant compounds. Furthermore, the potential of fruit peel as waste with nutraceutical applications was demonstrated.UID/05183/2025; CEECINST/00052/2021; MCIN/AEI/10.13039/50110001103
Resilience of innovation
No full textThe resilience of innovation approach extends the notion of resilience—commonly used to refer to socio-economic systems—to the innovation process. This text reviews conceptual perspectives on resilience (engineering, ecological, adaptive and transformative) and highlights innovation as a dynamic process, not just an outcome. Innovation resilience differs from related concepts such as innovation persistence and technological resilience, which focus on stability rather than the transformative nature of the process. In addition, we highlight that innovation resilience is a multi-level phenomenon and allows for the exploration of opportunities for social and environmental change in times of uncertainty