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A morphometric characterization of early CHICK embryo elongation
No full textThe chicken embryo has long been a pivotal model system to understand the cellular and molecular mechanisms driving amniote embryo development. Its easy access for in vivo experimentation, together with the development of ex ovo culture techniques, has made it a choice model system for elaborate experimental manipulations. Temporal progression of chick embryo development is classically categorized using the Hamburger and Hamilton staging system (Hamburger, V., & Hamilton, 1951). However, this offers limited temporal resolution when comparing embryos within the same developmental stage and may further be hindered by experimental conditions that directly impact the morphological structures used for stage identification. Here, we performed timelapse imaging of early chick embryonic stages HH4 to HH10 and obtained quantitative elongation data of multiple embryonic portions, yielding two valuable and freely accessible data resources for the chick research community. We identified length measurements capable of describing developmental time, thus enabling the alignment of independent embryos with temporal resolution. Notably, the head-fold (C-HF) showed a strong time correlation, even though it elongates above the primary embryonic axis. A morphometric characterization of HH stages further showed that C-HF length can discriminate HH stages of development, albeit with limited resolution. Finally, we present ChEEQ: Chicken Embryo Elongation Quantification (https://colab.research.google.co m/github/EmbryoClock/ChickElong/blob/main/ChEEQ/ChEEQ.ipynb), a new morphometric tool describing HH4-HH10 embryo elongation, that allows the comparison of user-input data with our reference dataset and is capable of inferring quantitative alterations to embryo developmental time using length measurements alone. Together, these resources open new avenues for investigating vertebrate embryo elongation and quantitatively assessing the effects of experimental interventions on development.SFRH/BD/146043/2019; COVID/BD/153553/202
CytroCell: a computational study in aqueous solution and infrared spectroscopic structural characterization
No full textA COSMO-RS conductor-like screening model for realistic solvation and molecular dynamics simulations conducted in GROMACS were used to gain insight into the structure and behaviour of CytroCell citrus nanocellulose in aqueous and more complex solutions, including the green solvent dihydrolevoglucosenone.
DRIFT spectroscopy was used to investigate the structure of CytroCell nanocellulose solid samples obtained via acoustic cavitation of lemon, orange, and red orange industrial processing waste. The computational and experimental results obtained are relevant to all forthcoming applications of this new family of nanocelluloses sustainably sourced from the citrus industry’s main waste product via the CytroCav circular economy process.D.D.1551.11-10-2022; PE0000000
Physical training protocols for improving dyspnea and fatigue in long COVID: a systematic review with meta-analysis
No full textObjective: This study aimed to evaluate physical training protocols for alleviating long COVID symptoms, especially dyspnea and fatigue, through a systematic review with meta-analysis. Method: Data were collected from EMBASE, LILACS, PubMed, Scopus, CINAHL, Web of Science, and grey literature (Google Scholar, medRxiv). Studies evaluating dyspnea and/or fatigue before and after physical rehabilitation, using validated questionnaires, were included. Studies lacking pre- and post-assessments or physical training were excluded. Two reviewers independently extracted data on intervention type, duration, frequency, intensity, and assessment methods for dyspnea and fatigue. Bias risk was evaluated using the Cochrane tool. Results: Combined methods, such as respiratory muscle training with strength and aerobic exercise, were common for long COVID symptoms. Aerobic exercise notably improved dyspnea and/or fatigue. Among 25 studies, four had a low risk of bias. Meta-analysis of two studies found no significant reduction in fatigue. Conclusion: Combined training methods, particularly aerobic exercise, alleviate dyspnea and fatigue in long COVID. More high-quality studies are needed to confirm these findings
Yeast species associated with industrial cultures of the marine microalgae tisochrysis lutea: temperature profiles and auxin production
No full textThis study provides the first systematic characterization of culturable yeast diversity associated with large-scale cultivation of Tisochrysis lutea. This marine haptophyte is widely used in aquaculture for its high content of essential fatty acids, pigments, and other bioactive compounds. Culture sampling was conducted at Necton S.A. facilities (Olhão, Portugal) over full production cycles from 5 L flasks until tubular photobioreactors during the months of May and June. The study aimed to identify and isolate the present yeast species and evaluate their physiological traits relevant to potential co-cultivation strategies. All retained isolates belonged to the phylum Basidiomycota, with six species identified: Rhodotorula sphaerocarpa (45%), R. mucilaginosa (20%), R. diobovata (13%), Vishniacozyma carnescens (16%), Naganishia diffluens (3%), and Moesziomyces aphidis (3%). Temperature growth profiles (10–40 ◦C), tolerance to artificial sea water, and auxin production were characterized, revealing that, except for V. carnescens, the yeast isolates grow optimally at 25–30 ◦C, within the ideal range for T. lutea cultivation. Results suggest that some of these marine yeasts, particularly R. sphaerocarpa and R. mucilaginosa isolates, could serve as biological enhancers of algal productivity, in situ. This foundational work supports future efforts to develop targeted yeast management or co-cultivation strategies, with the goal of improving biomass yield and metabolite production in industrial T. lutea photobioreactors
Linguistic loops and geometric invariants as a way to pre-verbal thought?
No full textWe introduce the concepts of linguistic transformation, linguistic loop and semantic deficit. By exploiting Lie group theoretical and geometric techniques, we define invariants that capture the structural properties of a whole linguistic loop. This result paves the way to a totally new line of research, employing tools from Lie theory and higher-dimensional geometry within language studies. But, even more intriguingly, our study hints to a mathematical characterization of the meta-linguistic or pre-verbal thought, namely of those cognitive structures that precede the language
Resisting or complying with neoliberal subjectification? Finnish and Portuguese non-traditional graduates and their educational ethoses
No full textThe Bourdieusian view of higher education (HE) emphasises its inherited nature and function in maintaining social hierarches. This is in conflict with the egalitarian and meritocratic ideas prevailing in some welfare regimes, such as those organised around Social Democratic or Conservative precepts. Moreover, the Bologna Process that began in the 2000s instilled the idea of employability as a broader goal of HE within the EU. This study investigates the experiences of non-traditional graduates (NTGs) from Finland and Portugal in relation to the trends affecting welfare regimes and the historical trajectories of HE. In the analysis, the ethoses of ‘HE as a virtue’, ‘human capital’, and ‘employability’ were identified. The ethoses are accompanied by varying degrees of resisting or complying with commodification of HE and neoliberal subjectification. HE institutions can be regarded as providing distinctive ethoses of NTGs that can be traced back to the influence of their respective welfare regimes.UID/05739/202
The vertebral column of flatfish: a review
No full textFlatfish (Pleuronectiformes) encompass fascinating fish species known for their high gastronomical value, rearing performances, and market prices, which attract both economic and scientific interest. Despite these attributes, flatfish exhibit unique morphological, developmental, and biological features, as well as distinctive swimming movements, which require special approaches in skeletal biology research, an area that remains relatively unexplored for this diverse group of fishes. These unique features emerge during metamorphosis, at the end of the larval period, when bilateral symmetric pelagic larvae gradually become asymmetric and undergo various morphological and physiological changes. Consequently, the skeletal characteristics of these species include a certain degree of asymmetry in the skeletal structures. These fish also present acellular bone (bone devoid of osteocytes).
Research on flatfish skeletons is crucial for improving animal welfare and promoting sustainable farming, as the literature indicates that more than 50% of the larvae and juveniles of different cultured flatfish can be affected by skeletal deformities.
This review aims to compile the available studies on the development of vertebral column deformities in flatfish in an integrative manner, addressing state-of-the-art research on the etiology, diagnostics, and innovative studies on this issue. It also covers the fundamental aspects of teleost skeletal development, particularly the flatfish vertebral column
Resident empowerment in all-inclusive context: cost–benefit perception and support for sustainable tourism development in a small island destination
No full textThis study examines the relationships among resident empowerment, perceptions of tourism costs and benefits, and support for sustainable tourism development (SSTD) in a small island destination dominated by all-inclusive resorts. Using survey data from 341 residents in Cape Verde and employing PLS-SEM analysis, results reveal significant relationships between empowerment, benefits, and SSTD. The perception of all-inclusive resorts' positive impacts moderates the relationship between empowerment and SSTD, while the perception of all-inclusive resorts' costs does not moderate any relationships. The study contributes to understanding how all-inclusive tourism development influences resident attitudes and support for sustainability in small island contexts. The findings underscore the importance of empowering residents and managing perceptions of tourism impacts to foster SSTD. Practical implications include the need for policies that promote local empowerment, equitable benefit distribution, and mitigation of negative impacts to ensure long-term sustainability of small island destinations and beyond.UI/BI/150802/202
Movement patterns of the invasive atlantic blue crab in a northeastern atlantic estuary
No full textThe movement ecology of invasive species discloses critical information to estimate ecological impacts and inform management policies to control their spread. The Atlantic blue crab Callinectes sapidus Rathbun, 1896, has successfully invaded coastal and estuarine ecosystems in southern Europe, making it urgent to understand fundamental aspects of its ecology in the non-native range. Recent studies identified key prey species for the Atlantic blue crab and quantified niche overlap with other crab species; however, the areas where the impacts are likely to be greater remain unexplored. Thus, we aim at studying its spatial ecology and assess which areas of a tidal estuary (Guadiana, Portugal) are predominantly used by the invasive Atlantic blue crab through acoustic telemetry. A total of 24 specimens were collected in the estuary in 2022, tagged, and tracked for up to nine months using four acoustic receivers located at 1, 3, 11, and 20 km from the river mouth. Two predominant patterns were observed: 1) movements along the estuary synchronized with the tide, and 2) extended residency periods in the transition between the middle and upper estuary. These findings can now inform policy makers and be used to better design local management plans, namely in upper areas of the Guadiana estuary where the species tends to aggregate, making it easier to be targeted by artisanal fisheries, when compared to coastal areas.COVID/BD/153280/2023; 2021.00956.CEECIND; 2023.07953.CEECIN
A glycymeris-rich unit as evidence of a late pleistocene tsunami event from NW algeria: a biostratigraphic, taphonomic, and sedimentological approach
No full textCompared to the extensive research carried out on the Neogene deposits of the Lower Chelif Basin, the Pleistocene series is still poorly studied, with no detailed lithological succession published to date. This study focuses on the Glycymeris-rich Unit (GRU) along the coastal area of the Hachacha Plateau in Northwestern Algeria. This unit unconformably overlies Miocene, Pliocene, and Pleistocene basements. The latter was identified for the first time in this work using a biostratigraphic approach based on calcareous nannofossils and planktonic foraminifera. The GRU is interpreted as a tsunami-related deposit, formed in a coastal environment (foreshore/backshore) during the upper Pleistocene, corresponding to the Last Interglacial period, i.e., Marine Isotopic Substage 5e (MIS 5e). This interpretation provides a first multidisciplinary description of a tsunami deposit in Algeria that is supported by distinctive biotic, taphonomic, and sedimentological features. The deposits contain a mixture of marine organisms from different ecological zones (supralittoral to shallow circalittoral biocenoses), including molluscan assemblages such as the so-called Senegalese fauna (bivalves and gastropods), sponges, serpulids, coralline algae and corals. Occasionally, rare terrestrial snails are also found mixed with the marine fauna. Taphonomic analysis reveals low percentages of boring, absence of encrustation, and excellent shell preservation, suggesting that powerful waves eroded sediment masses and transported them inland from deeper areas beneath the taphonomic active zone. The predominance of sharp-edged fragmented shells, chaotic arrangements with oblique to vertical shell orientations and the good shell sorting, indicates transport by mass flows and rapid deposition during an extreme event – a tsunami –, distinguishing these deposits from those associated with gradual and oscillatory flows, such as storm events. Sedimentological characteristics, including irregular erosive base, lateral facies variations, wide grain size ranges (clay to boulders), normal and inverse grading, and diagnostic structures (both fragile and hard-rock rip-up clasts, high-energy flow features such as horizontal and oblique laminations, and hummocky cross-stratification, injection of sediment into the substrate, imbrication of large angular boulders and soft sediment deformation structures), combined with the active tectonic context of Northwestern Algeria support the interpretation as a seismically triggered tsunami and enhances the understanding of this type of deposits in similar coastal settings.FCT/2023.07418; 2023.07418.CEECIND/CP2845/CT0001; POCI-01–0145-FEDER-00682; LA/P/ 0048/2020; (M1.1.a/005/Funcionamento-C-/2016, CIBIO-A; M1.1.A/INFRAEST CIENT/A/001/2021); LA/P/0068/202