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Trait-based vulnerability and tolerance thresholds of tropical mollusks in light of projected increases in climate-change stressors
No full textExtreme climate conditions increasingly threaten worldwide coastal biodiversity. We applied a trait-based approach to quantify the tolerance thresholds of 13 mollusk species from five tropical coastal habitats, using controlled experiments that simulate extreme temperature, salinity, submersion, and desiccation stress. Survival was analyzed in relation to functional traits, including isolation from ambient conditions (presence/absence of shell closure and/or operculum), respiration mode (branchial or pulmonate), shell thickness, and habitat type. Thermal safety margins (TSMs) were also projected under future climate scenarios. Species that possess isolation traits consistently survived across stress conditions. Bivalves generally tolerated higher temperatures and broader salinity ranges than gastropods, and pulmonate gastropods experienced high mortality under both prolonged submersion and desiccation. Desiccation tolerance was strongly associated with the ability to isolate. Thicker shells provided limited protection against extreme temperatures but did not protect taxa with narrow salinity tolerances. Projected TSMs indicated that species from mangrove and oyster-bank habitats will be subject to temperatures that exceed their upper thermal limits before the end of this century. Vulnerability to climate change arises from a combination of functional traits and habitat context. By addressing multiple climate-related variables, i.e., temperature, salinity, inundation, and desiccation, all of which are shifting with global climate change, this study identified combinations of traits that will confer tolerance to tropical mollusks under future conditions and identified taxa that will likely be at risk. This study fills critical data gaps for tropical habitats worldwide and provides a framework for predicting biotic responses to climate extremes.UID/04326/2025; UID/PRR/04326/202
Prokaryotic community structure and auxin biosynthesis in early developmental stages of farmed atlantic nori (Porphyra spp.)
No full textIntroduction: Algal-microbiome interactions are considered pivotal for host health and development. Current understanding of the diversity and function of algal-associated microorganisms in aquaculture settings remains limited, preventing the development of microbiome-based solutions for sustainable algal growth.Methods: We employed cultivation-dependent and -independent approaches to determine the structure of bacterial communities associated with farmed Atlantic Nori (Porphyra dioica and Porphyra umbilicalis) at early developmental stages. 16S rRNA gene amplicon sequencing and cultivation of bacterial symbionts were performed for algal and culturing water samples harvested from indoor photobioreactors at stages S1 (conchocelis cultures growing vegetatively), S2 (conchosporangia), and S3 (young blades).Results: The phyla Pseudomonadota (Alpha- and Gammaproteobacteria classes) and Bacteroidota were dominant in algal samples, followed by Planctomycetota, Actinobacteriota, and Verrucomicrobiota. At the phylotype level, these communities were highly structured throughout the host’s life cycle. Uncultivated lineages Sva0996 (Actinomycetota), OM190 (Planctomycetota), Pir4 (Planctomycetota), and the genera Blastopirellula, Algoriphagus, Hyphomonas, and Marinobacter, among others, were enriched in algal samples and presented significantly different abundances across developmental stages. In some cases (e.g., genera Aquimarina, Sulfitobacter, Maribacter, and Nonlabens), those changes were also observed in culturing water. Moreover, the genera Ensifer (Rhizobiaceae), Paraglaciecola (Alteromonadaceae), and the uncultivated lineages DEV007 (Verrucomicrobiota) and Pir4 (Planctomycetota) were consistently present in P. dioica and P. umbilicalis samples at multiple developmental stages. Several Porphyra-associated bacterial genera and putative novel species, mostly belonging to the families Roseobacteraceae, Flavobacteriaceae, and Alteromonadaceae were identified via cultivation. Many cultured members of the Porphyra microbiome produced the growth-promoting hormone auxin, particularly those belonging to the genera Alteromonas, Marinobacter, Sulfitobacter, Leucothrix, and Roseovarius.Discussion: This study unveils complex, phylogenetically distinct, and temporally structured bacterial communities possessing algal morphogenesis-inducing capacities during early developmental stages of Porphyra spp., highlighting the potential of microbiome-based interventions for sustainable growth of marine algae in aquaculture.CEECIND/00788/201
Assessing the role of CT imaging in identifying candidates for neoadjuvant chemotherapy in right colon cancer: a critical analysis
No full textBackground and purpose Standard treatment for localized right colon cancer is radical surgery, followed by adjuvant chemotherapy for stage III or intermediate MSS and high-risk stage II tumours. Recent studies suggest a benefit from neoadjuvant chemotherapy (NAC), particularly for T4b and/or N+tumours. Patient selection for NAC relies on CT-based clinical staging, but the accuracy of CT in detecting high-risk features is variable, raising concerns about potential overtreatment. The study aims to demonstrate the accuracy of CT staging of the right colon with the purpose of indicating neoadjuvant CT. Methods Patients undergoing curative right hemicolectomy between 2013 and 2023 at two Portuguese institutions were included. All had preoperative CT; those receiving NAC were excluded. Sensitivity, specificity, positive predictive value, and negative predictive value of CT in identifying T4b and N+tumours were calculated by comparing clinical (cTNM) and pathological (pTNM) staging. Results Among 165 patients (48% male, mean age 70.5 years), CT showed low sensitivity (26%) but high specificity (91%) for pT4b tumours, with a tendency toward understaging. For nodal disease, sensitivity was 87% and specificity 41%. Only 57% of cT4b and/or cN+cases confirmed at least one unfavorable pathological factor, implying potential overtreatment in 43% of patients if NAC were applied solely based on CT findings. Conclusion CT remains the standard for clinical staging but demonstrates limited accuracy in identifying high-risk right colon cancers. NAC decisions should integrate additional criteria beyond CT findings to avoid overtreatment
Impression management, government agencies' regulation and analyst forecasts: empirical evidence from an emerging market
No full textPurpose- This study aims to investigate the relationship between government agencies' regulation and analyst forecasts in an emerging market and whether this relationship is mediated by impression management in earnings press releases.Design/methodology/approachThe sample consists of 1,816 quarterly observations of Brazilian listed firms from 2003 to 2021, based on data from Thomson Reuters (R). The impression management of the sample firms is obtained by analyzing their earnings releases using the Watson Natural Language Understanding (NLU) platform developed by IBM (R). We employ a manual firm-level classification procedure to detect regulated and non-regulated firms by government agencies.FindingsBased on structural equation modeling, the findings suggest that firms regulated by government agencies present, on average, lower levels of impression management in earnings press releases. Additionally, we find that the level of firms' impression management, in turn, is negatively related to analyst forecast errors. These empirical results indicate that impression management in earnings press releases is a crucial mediating channel between government agencies' regulation and analyst forecast errors. Moreover, we find that government agencies' regulation has a positive and direct effect on analyst forecast errors, possibly due to its impact on other firm-level incentives and market dynamics, which may be positively or negatively associated with analyst forecasts.Originality/valueThis study contributes to the previous literature on the relationship between government agencies' regulation and analyst forecasts by theoretically discussing and empirically analyzing the mediating role of impression management as an important factor in this relationship, exploring the various facets through which state regulation ends up changing the structure of the informational environment in which companies are located. An important debate for the emerging markets literature is also provided, and policy discussions are featured.UID/06522/2025, 404658/2023-
Destination marketing organisations: envisioning a regenerative tourism operating model
No full textThis study critically evaluates Destination marketing organisations (DMOs) within the paradigm of regenerative tourism, shifting from conventional operating models primarily centred on marketing and economic growth to a regenerative-oriented framework. Building on the scarce tourism transition literature, this study integrates participatory normative scenario-building with the Three-Horizons framework in workshops with 26 DMO managers. It examines current DMO activities, identifies key operating characteristics, and explores how these align with either traditional or regenerative approaches. The findings highlight a need for DMOs to broaden their activities beyond traditional promotion, to include stewardship, management and regenerative marketing. Theoretically, this study contributes to advancing the understanding of regenerative tourism within DMOs, helping bridge the gap between its theoretical foundations and real-world practice. Methodologically, it provides a replicable and adaptable tool for participatory foresight in tourism governance. It contributes a manifesto offering actionable pathways to guide policymakers and DMOs in transitioning towards regenerative tourism futures.UID/04020/202
Phantom cosmology with arbitrary potential: new accelerating scaling attractors
No full textIn this article, we investigate the existence of accelerating scaling solutions in coupled phantom cosmology without assuming any specific potential for the phantom scalar field. The coupling between phantom dark energy and dark matter is motivated by the warm inflationary paradigm, with the dissipation coefficient assumed to be either constant or variable. The evolution equations are written in the form of autonomous systems, whose stability is studied using methods of qualitative analysis of dynamical systems. For this analysis, the only requirement imposed on the otherwise arbitrary phantom potential is that a particular dynamical variable, defined in terms of the potential and its derivative, must be invertible. For such a generic potential, we show that accelerated scaling solutions do exist, for both constant and variable dissipation coefficients. Although there is a limitation to these scaling solutions – specifically, the current stage of accelerated expansion is not preceded by a long enough matter-dominated era – our results show that the existence of a direct coupling between phantom dark energy and dark matter yields great potential for addressing the cosmic coincidence problem.UID/04106/2025; UID/PRR/04106/202
First insights on chemical nature and bioactivity of surface mucus from the Antarctic sponges Mycale (Oxymycale) acerata and Dendrilla antarctica
No full textThe mucus produced by the Antarctic sponge species Mycale (Oxymycale) acerata and Dendrilla antarctica was ana¬lyzed to investigate its chemical composition and assess potential cytotoxic activity against human tumor cell lines. The mucus samples exhibited a high-water content (98–99%), while inorganic salts represented most of the total dry weight (67.1 ± 2.3%). Sodium was the most abundant element, accounting for 75% in D. antarctica and up to 82% in M. acerata. Other major elements—including magnesium, potassium, and calcium—comprised 3–10% of the inorganic fraction. Pro¬tein content was estimated at 0.44% for M. acerata and 5.63% for D. antarctica, with a carbon-to-nitrogen (C/N) ratio between 3 and 5. Elemental analysis was supported by μFT-IR spectroscopy, which confirmed the presence of inorganic salts, water, and proteinaceous materials. Further characterization by 1H NMR spectroscopy and LC–MS revealed the pres¬ence of amino acids, peptides, sugars, carboxylic acids, nitrogenous bases, and their derivatives. Notably, oxylipin concen¬trations ranged between 1 and 3 ng/L. In addition, M. acerata mucus demonstrated antiproliferative activity, selectively inhibiting the growth of Malme-3 M melanoma cell lines, thus suggesting a potential for cytotoxic effects. Overall, these findings provide the first chemical characterization of Antarctic sponge mucus, providing first insights for its potential exploitation as a novel source of bioactive compounds.EMBRC.PT ALG-01-0145-FEDER-02212
The southern african stone age site index (SASSI): a spatial, chronological and contextual resource for archaeological research
No full textSouthern Africa possesses a deep archaeological record, spanning more than a million years, which has attracted over a century of research. As a result, it offers one of the densest and most detailed pictures of Stone Age occupation history in Africa. However, certain time periods and regions have featured more prominently in research, particularly the later Middle Stone Age of the coastal and mountain zones. Moreover, the modern emphasis on absolute dating and well-resolved chronologies often excludes open-air and surface sites from reviews and syntheses, meaning that environments lacking deep, stratified rock shelters remain underrepresented. To address this, the Southern African Stone Age Site Index (SASSI) provides a centralised, openly accessible resource for archaeological research, featuring 492 reported Earlier, Middle and Later Stone Age sites from South Africa, Lesotho, Eswatini and Namibia. It includes both dated and undated sites, and encompasses diverse contexts. The database integrates spatial, chronological, cultural and contextual information, following FAIR data principles. While previous synthetic datasets have emphasised chronology and systematics, SASSI instead prioritises spatial coverage, offering a foundation for new perspectives on demography, settlement patterns, and landscape use in southern Africa’s past.TENURE.008/CP00040/CT0000
Early Pleistocene (1.94–1.46 Ma) records for the upper mediterranean outflow Water branch reveal low and high latitude climate influences
No full textThe Mediterranean Outflow Water (MOW), modified by paleoceanographic conditions and tectonic processes, played a significant role in the formation of sediments drifts along the Iberian Margin. Using sediment samples from IODP Hole U1387C, we explore the Early Pleistocene history of the upper MOW core above the central Faro Drift in the Gulf of Cadiz. The time series of benthic foraminifer stable isotope and grain size related data have a rigorous stratigraphic framework consisting of nannofossil biostratigraphy and paleomagnetic and delta 18O stratigraphy. The paleoenvironmental records are supplemented by natural gamma ray downhole logging data. Above the hiatus associated with the youngest dolostone, sandy to muddy contourite sedimentation started at 1.946 Ma, i.e., within Marine Isotope Stage (MIS) 74, at IODP Site U1387, slightly younger than at IODP Site U1389. Formation of contourite layers, reflected in the sortable silt and sand percentage records, strongly reacted to precession forcing, including semi- and quarter-precession cycles. The majority of the contourite beds developed during stadial (colder) climate periods, like previous observations from the Early to Late Pleistocene. Formation of contourite layers within MIS 53, MIS 55 and MIS 65, however, appear to be linked to the prevailing atmospheric conditions over North Africa. Periods of poor ventilation in the upper MOW were linked to insolation maxima and reduced ventilation in the Mediterranean Sea. Here, MIS 51 presents a peculiar case as poor ventilation reached from the surface to the lower North Atlantic Deep Water range, reflecting unique interglacial conditions that merit future exploration.UID/04326/2025, UID/PRR/04326/2025, PID2021-128322NB-I00 and PID2024-158309NB-I0
Unravelling the chemical nature of the spawning-inducing pheromone (SIP) in the pacific oyster (Magallana gigas)
No full textIn external fertilisation, spawning synchrony is often mediated by pheromones. However, their chemical nature is rarely well-established; this is particularly true for bivalves. This study used an electrophysiological technique—the electro-osphradiogram (EOsG)—to investigate the spawning-inducing pheromone (SIP) in the Pacific oyster (Magallana gigas), a species of economic and environmental relevance. Recording the electrophysiological response of the osphradium to conspecific sperm milt and its fractions, we show that the SIP is multicomponent, likely proteinaceous—with at least one component linked to the spermatozoa and the other components in free solution—and all resistant to freezing. At least three active components are involved: one of about 35 kDa, one between 3 and 10 kDa and one of less than 3 kDa. All three, alone, evoke responses from the osphradium, but all three must probably be present to evoke the full biological response—gamete release— in the receiver. All three are likely polar; none were retained by a range of solid-phase
extraction cartridges. We suggest that the EOsG will be useful to isolate and identify the individual components of the oyster SIP. Successful identification of the SIP will represent an important step towards more sustainable and efficient bivalve hatchery practices.UID/04326/2025; UID/PRR/04326/202