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Dominant effects of the antiepileptic drug carbamazepine over climate change stressors on mytilus galloprovincialis toxicity
No full textPharmaceuticals have become ubiquitous in marine realms, raising concerns about their ecological effects. This study investigates the ecotoxicological impact of the antiepileptic drug carbamazepine on marine mussels (Mytilus galloprovincialis) under increased seawater temperature and salinity, reflecting projected climate change scenarios. Mussels were exposed to carbamazepine (CBZ, 5 μg L− 1 ) for 28 days in both current (17 ◦C and salinity 35) and predicted (23 ◦C and salinity 40) conditions. A multiple-biomarker approach was employed to assess alterations in energy balance, antioxidant and biotransformation systems, membrane damage, neurotoxicity, and genotoxicity in gills and digestive glands. The results indicated that CBZ caused significant oxidative stress, disruption in energy metabolism, and neurotoxic and genotoxic effects, regardless of the combination of stressors. Moreover, biomarkers were modulated by the time of exposure, suggesting a time-specific response in mussels exposed to either a single or multiple stressors. The findings underscore the complex interplay between pharmaceutical pollution and climate change stressors. This study provides crucial insights into the toxicity of pharmaceuticals in marine environments under future climate change scenarios. To our knowledge, this is the first study to investigate the effects of CBZ on marine mussels in conjunction with the simultaneous rise in seawater temperature and salinity.UID/50017/202
Impact of trace elements of wastewater from steel and iron industry on benthic communities of Bizerte lagoon (Tunisia)
No full textThe metallurgical industry is amongst the most water-intensive industrial sectors. It generates significant quantities of trace elements (TEs) in wastewater, which are largely discharged into the aquatic ecosystems. The purpose of this study is to investigate the influence of TEs in wastewater effluent (WWF) from the Tunisian Iron and Steel Company "EL FOULADH" on the Bizerte Lagoon ecosystem. To this end, it entailed collecting samples of EL FOULADH WWF, Bizerte Lagoon water, and sediments from seven stations located both adjacent and far (-0.12, 0.34, 5.37, 7.58, 8.26, 8.65, 11.96 m) from WWF discharge points and measuring their TEs contents. Additionally, sediment contamination indices were estimated and bacterial and meiofaunal community assemblages were analyzed. Both univariate (ANOVA) and multivariate (PCA/CCA/Cluster) analysis revealed significant dissimilarities in the distribution of TEs, meiofaunal, and bacterial communities between downstream and upstream WWF discharge points. The comparison of abiotic and biotic variables revealed specific benthic assemblages for the station closest to the WWF discharge points. Interestingly, these sediments are distinctively characterized by the total disappearance of copepods. These findings offer us valuable information, pointing out to specific meiofauna and bacterial taxa, TEs sediment content affects the benthic assemblage of Bizerte lagoon via modeling trophic relationships
Effect of warming on European green crab (Carcinus maenas) populations from larvae to sexual maturity
No full textUnderstanding the effects of climate change on the physiology of marine species, particularly during their early life stages (larvae and juveniles), is essential for predicting population dynamics. Carcinus maenas is a widely distributed species of significant ecological and economic importance. This experimental study investigates the effects of warming on the early life stages of the European green crab, C. maenas, through two complementary experiments: (1) larval development and survival were assessed under three temperature regimes-approximately 18.5 degrees C (representing the annual average Portuguese seawater temperature between 1980 and 2020, used as the control), and two projected climate change scenarios: RCP 4.5 (+1.5 degrees C) and RCP 8.5 (+3.5 degrees C), and (2) juvenile survival and growth were monitored in mesocosms from early settlement to sexual maturity. Results indicated that larval mortality exceeded 90 % across all treatments, with 75 % occurring within the first 8 days (95 % CI: 7-8), and that warming enhanced larval survival, with the RCP 4.5 scenario yielding the highest survival rates compared with the control. Additionally, warming also reduced the pelagic larval duration, which declined from 27 (+/- 2) days at 18.5 degrees C to 16 (+/- 1) days at 22 degrees C. Similarly, the duration of the megalopa (settlement) stage decreased from 10 to 6 days. Therefore, despite high mortality, accelerated development under warming may enhance population resilience. Juvenile mortality was also high, with 50 % of settled individuals dying within the first 50 (95 % CI: 31-46) days, and differences in growth and survival between sexes were observed: females reached sexual maturity faster than males 83 +/- 12 and 109 +/- 20 days, respectively. Moreover, only 24 % (95 % CI: 16-34) of the settled females reached sexual maturity, compared to just 9 % of males (95 % CI: 5-18). These results indicate that C. maenas reach reproductive maturity within six months. The biological data reveal a fast growth increment, high larval and juvenile mortality, and suggest that projected climate change scenarios through the end of the century will have a limited impact on the species' population dynamics and recruitment.101071300, CEECIND/CP1639/CT000
Culture to commitment: hr blueprint for sustainable hospitality-tourism academia growth
No full textThis study examines the relationship between organizational culture (OCu), job satisfaction (JBS), and organizational commitment (OCo) in Indian hospitality and tourism higher education institutions (HEIs) using the OCTAPACE framework. Grounded in Social Exchange, Organizational Support, and OCu theories, it assesses cultural influences on commitment directly and via JBS. Data from 386 teaching and non-teaching staff were collected through stratified purposive sampling, using validated scales and acknowledging limitations from the lack of a central database. Analysis employed Partial Least Squares Structural Equation Modelling (PLS-SEM). Results show that OCu significantly enhances JBS and commitment, with JBS partially mediating this link. Findings offer actionable insights for HR policy, leadership strategies, and employee retention in service-oriented academic contexts
Unlocking the potential of other effective area-based conservation measures (OECMs) for achieving conservation targets: a global scoping review
No full textOther Effective Area-based Conservation Measures (OECMs), introduced by the Convention on Biological Diversity (CBD), refer to areas outside formal protected-area networks that deliver effective and enduring in situ biodiversity conservation. This scoping review systematically examined global approaches to identifying and evaluating potential OECMs. Analysing 99 studies covering 694 case studies and 237 000 potential sites, we found that potential OECMs are widespread, particularly in Asia and terrestrial environments, with most initiatives led by the environmental sector. Assessments relied largely on qualitative expert knowledge, with limited application of analytical methods. Although CBD criteria were commonly applied, contributions of related to ecosystem services and socio-cultural values were often overlooked. Effectiveness evaluations showed considerable uncertainty, with over one-third of case studies reporting inadequate evidence of conservation outcomes. The review emphasises the need for standardised assessment methodologies, improved decision-support tools, and socio-cultural integration to enhance OECM recognition, particularly under the 30 × 30 conservation biodiversity target
Anthony E. Marks (1938–2025): pioneer of the palaeolithic
No full textAnthony “Tony” Edward Marks passed away on August 15, 2025, at his home in Santa Fe, New Mexico, at the age of 87. Tony’s passing marks the end of a remarkable career in archaeology that spanned nine countries, four continents, and a quarter million years of prehistory. Not only did he fundamentally shape how we understand the Palaeolithic record, but he transformed our very perception of lithic technology, teaching us how to find the profound depth of meaning in stone.
A proud New Yorker, Tony was born, raised, and edu¬cated in Manhattan. As a young student at Columbia Uni¬versity eager to pursue his love of European medieval art and churches, he was promptly taken aside by the anthropol¬ogy department head, Marvin Harris, who (rather forcefully as Tony would recall) urged him to stick with archaeology. Tony’s professional career began with the UNESCO Nubian salvage campaigns of the 1960s. As Lake Nasser rose behind the Aswan High Dam, Tony mapped prehistoric sites along the east bank of the Nile before their inundation. During the Nubian salvage project, he documented several key Palaeo¬lithic industries, including an array of assemblages defined by the presence of Nubian core technology. He could never know at the time how that discovery would unexpectedly resurface decades later, at the end of his career
Using reflectance to measure chlorophyll a in corals: calibration and implications of skeletal optical properties
No full textClimate change-driven coral bleaching and associated chlorophyll (Chl) loss increasingly threaten coral reefs, highlighting the need for non-invasive, cost-effective tools to assess corals’ physiological condition. Researchers have explored the reflectance-based Normalized Difference Vegetation Index (NDVI) as a proxy for Chl a. However, almost no calibration curves exist to date; thus it remains unknown if the relationship between Chl a and NDVI differs among coral species, and whether it is influenced by skeletal optical properties. Here, we correlated Chl a content to NDVI in three coral species with different skeletal morphologies and reflectance modes across a range of health states (i.e., bleaching states). We found a strong positive relationship between Chl a and NDVI in all species, validating NDVI as a proxy for Chl a in corals. However, this relationship is non-linear, showing deviations at the highest and lowest ends of the pigmentation spectrum. We propose that in healthy states, this non-linearity is due to pigment self-shading, whereas in bleaching states, it is caused by backscattering of light by the increasingly exposed coral skeleton, because pigment loss enhances absorption by the remaining Chl a pigments and lowers, rather than increases, reflectance. To avoid Chl a under- or overestimation, we recommend to log-transform Chl a and create species-specific calibration curves. Overall, the non-invasive, repeatable, and scalable nature of reflectance measurements and NDVI make them valuable tools for assessing coral health both ex- and in situ. They provide a comprehensive view of the holobiont’s physiological condition and hold potential for broader applications in reef-scale monitoring, remote sensing, coral restoration, and conservation
Modulation of a RBP as potential therapeutic strategy for SCA2
No full textSpinocerebellar ataxia type 2 (SCA2) is one of the nine polyglutamine disease (polyQ), characterized by an abnormally long expansion of the adenine-cytosine-guanine (CAG) trinucleotide within each respective disease-associated gene. PolyQ diseases are dominantly inherited neurodegenerative disorders in which, affected people experience a myriad of highly debilitating motor symptoms. SCA2 arises from a mutation within the coding region of the ATXN2 gene, which is translated into ataxin-2 protein bearing an abnormally long polyQ tract. This mutant protein is prone to aggregate and known to gain toxic function, which is in the basis for disrupting several molecular pathways, which ultimately lead to neuronal death, within specific brain region, including the pons and the cerebellum. Among other, these disrupted pathways might include aberrant RNA metabolism or even loss of cellular proteostasis. Unfortunately, there are no therapeutic options capable of preventing such pathways to became dysregulated, which mean that people affected by SCA2 have no therapies able to cure nor delay the disease progression, ultimately suffering a premature death. To understand whether reestablishing cellular proteostasis could, in fact mitigate SCA2-associated pathology we sought to evaluate the impact of expressing HSPA8, a crucial chaperone involved in the mechanism of proteome homeostasis. In this work we used both in vitro and in vivo approaches to assess whether HSPA8 expression was able prevent SCA2 pathology. We observed that in in vitro models of SCA2 and in an in vivo lentiviral model of this disease, HSPA8 expression was able to both prevent the number of ataxin-2 aggregates and at the same time preserve the neuronal tissue. This work suggests that the expression of HSPA8, a chaperone involved in the mechanism of cellular proteostasis, was able to mitigate SCA2-associated disease hallmarks. Therefore, HPSPA8 could represent a novel therapeutic target for SCA2.A ataxia espinocerebelosa do tipo 2 (SCA2, do inglês spinocerebellar ataxia type 2) é uma doença neurodegenerativa, autossómica dominante, que se encontra inserida num grupo de nove doenças conhecidas por doenças de poliglutaminas (PolyQ), e que partilham entre si diversos mecanismos patológicos. De entre as diversas formas hereditárias de ataxia, a SCA2 representa a segunda mais prevalente a nível mundial. Esta doença caracteriza-se pela progressão de um conjunto de sintomas debilitantes, sendo a ataxia cerebelosa o sintoma clínico mais predominante. Adicionalmente, os doentes de SCA2 podem também apresentar outros sintomas resultantes da degeneração cerebelosa como a disartria, rigidez muscular, disfagia, assim como outras manifestações não cerebelosas, como movimentos sacádicos oculares lentos, contrações musculares involuntárias e mioclonia. Atualmente, os tratamentos disponíveis são unicamente sintomáticos, não existindo uma terapia eficaz, capaz de atrasar ou parar a progressão da doença.
A SCA2 surge como consequência de uma expansão anormal do trinucleótido citosina-adenina-guanina presente na exão 1, na região codificante do gene ATXN2. A expansão anormal de CAGs é conhecida por estar na raiz da patologia inerente à SCA2. Esta mutação conduz à síntese de uma proteína – ataxina-2 – que contém uma sequência de glutaminas anormalmente expandida, que quando, igual ou superior a 32 glutaminas é responsável pela manifestação do fenótipo de SCA2. A proteína ataxina-2, em condições normais, desempenha funções biológicas essenciais, entre as quais modificações pós-transcricionais, regulação da tradução, formação de grânulos de stress, homeostase do cálcio, assim como processos de endocitose e reorganização do citoesqueleto. No entanto, a forma mutante da ataxina-2 tende a agregar, conduzindo à formação de oligómeros e, eventualmente, à acumulação de agregados proteicos insolúveis capazes de gerar toxicidade neuronal e desregular diversos mecanismos moleculares e celulares. As propriedades tóxicas da ataxina-2 mutante em conjunto com a formação de agregados, são por isso, responsáveis pela disfunção e morte de populações neuronais específicas, nomeadamente as células de Purkinje.
As células têm a capacidade de se adaptar a diversos estímulos intrínsecos e extrínsecos, promovendo uma resposta através de diferentes mecanismos que facilitam a adaptação das mesmas a contextos específicos, e os neurónios não são exceção. A resposta celular pode envolver processos de metabolismo de RNA ou até mesmo mecanismos de manutenção da homeostase do proteoma (proteostase). Por um lado, modificações pós-transcricionais são reguladas por RNA-binding proteins (RBPs), que desempenham uma função importante no metabolismo de RNAs e, por isso, determinando o seu destino. No que respeita à proteostase celular, esta é executada por proteínas de diversas classes conhecidas por chaperonas moleculares. As chaperonas desempenham uma ação essencial no eficiente enrolamento de proteínas recém sintetizadas, na prevenção da formação de agregados proteicos derivados da má conformação de proteínas, no re-enrolamento de proteínas e, em última instância, no direcionamento de proteínas para vias de degradação. De uma forma geral, as chaperonas são proteínas auxiliares que atuam sobre outras proteínas com conformações anormais, impedindo a sua acumulação e eventual agregação, contribuindo por isso para a manutenção da proteostase. Recentemente, diversos estudos em doenças neurodegenerativas, incluindo as doenças de polyQ evidenciaram a importância das RBPs e das chaperonas moleculares como potenciais alvos terapêuticos. De facto, nas doenças de agregação, nomeadamente na SCA2, a formação de agregados proteicos aberrantes, conduzem à disrupção de múltiplos mecanismos celulares, entre os quais a disfunção dos mecanismos de proteostase celular. Estes agregados, são também conhecidos por estabelecer interações anormais com outras proteínas que são sequestradas das suas funções normais, o que por fim, pode conduzir à morte neuronal.
Deste modo, e sendo a SCA2 uma doença atualmente sem cura, o objetivo principal deste trabalho foi tirar partido das propriedades das RBPs e das chaperonas moleculares, através da modulação de uma RBP/chaperona específica, denominada HSPA8, como um possível alvo terapêutico na mitigação desta doença. Expectavelmente, o uso da HSPA8 iria modular a proteostase celular, e como resultado preveniria os efeitos negativos da proteína ataxina-2, conduzindo assim à mitigação da neuropatologia associada à SCA2. De forma a atingir este objetivo, o trabalho aqui apresentado foi dividido, essencialmente, em três fases.
Na primeira parte deste estudo, fomos averiguar o efeito da sobrexpressão da HSPA8 num modelo de SCA2 in vitro utilizando células N2a. Com esta estratégia, foi possível observar que a sobrexpressão da HSPA8 permitiu a redução do número de células com agregados quer na forma wild-type (WT), quer em formas mutante da ataxina-2. Contudo, não foi possível identificar alterações nos níveis da proteína ataxina-2 mutante. Foi ainda possível constatar que a expressão da HSPA8 não produziu um efeito tóxico.
Na segunda parte deste trabalho, averiguou-se se os resultados obtidos no modelo in vitro de SCA2 poderiam ser traduzidos para um contexto in vivo mais robusto. Para isso, foi utilizado um modelo lentiviral de SCA2 de murganhos co-injetado no estriado com partículas lentivirais que codificavam para a ataxina-2 mutante e para a HSPA8, ou como controlo, co-injetado da mesma forma com a ataxina-2 e GFP. O impacto da expressão da HSPA8 em sinais neuropatológicos de SCA2 foi observado e, foi possível identificar uma redução no número de agregados de ataxina-2 mutante. Para além disso, verificou-se uma redução da perda do marcador neuronal DARPP-32, aquando da expressão da HSPA8. Adicionalmente, foi possível constatar que a HSPA8 não induziu alterações nos níveis de proteína ataxina-2 mutante. Marcadores de neuroinflamação, nomeadamente da ativação da microglia e da ativação de astrócitos, tais como IBA1 e GFAP, respetivamente, foram analisados. Verificou-se que, a expressão da HSPA8, parecia não exacerbar eventos de microgliose e astrogliose.
Por último, avaliou-se possíveis alterações nos níveis basais da HSPA8 num contexto in vivo, utilizado um modelo lentiviral de murganho de SCA2. Assim sendo, os níveis de expressão da HSPA8 foram acedidos e não foi possível detetar alterações entre murganhos do modelo lentiviral de SCA2 e murganhos WT. Deste modo, confirmando que a nossa estratégia terapêutica, se baseava na sobrexpressão da HSPA8, ao invés da reposição dos seus níveis.
Em suma, este estudo permitiu perceber que a sobrexpressão da HSPA8, originou resultados concordantes, quer num contexto in vitro, quer num contexto in vivo de SCA2. A expressão da HSPA8 permitiu a redução do número de agregados, mas não dos níveis da proteína ataxina-2 mutante, o que poderá ser sugestivo que de, de facto, a HSPA8 está a direcionar a proteína ataxina-2 para mecanismos de restabelecimento da sua conformação, em vez de direcioná-la para as vias de degradação, sugerindo assim, uma recuperação da proteostase celular. Deste modo, o presente estudo realça a HSPA8 como um novo potencial alvo terapêutico, não apenas com o intuito de tratar sintomaticamente os pacientes de SCA2, mas com a capacidade atrasar ou mesmo curar esta doença debilitante
From destination attributes to tourist satisfaction: novelty-seeking as a bridge between liminality and place attachment
No full textThis study analyses how destination attributes influence tourist satisfaction via perceived quality, price, and safety, and how these relationships differ by novelty-seeking orientation. Framed at the intersection of liminality and place attachment, novelty-seeking is conceptualised as the behavioural mechanism linking extraordinary experiences to emotional bonds with place, offering the first empirical integration of these frameworks in tourism research. Using data from 1,488 tourists visiting the Algarve (Portugal) in 2022–2023 and Partial Least Squares Multigroup Analysis (PLS-MGA), the results show that for conservative tourists, destination attributes enhance perceived quality, lower perceived prices and safety concerns, and increase satisfaction. For adventurous tourists, satisfaction is driven mainly by perceived price and is negatively affected by in situ safety concerns, indicating that novelty-seekers do not uniformly discount risk. The findings highlight how novelty-seeking conditions cognitive pathways to satisfaction and inform market segmentation strategies aligned with distinct motivational orientations.UID/04020/202
Transdisciplinarity in water management: a systematic review of concepts, practices, and challenges
No full textTransdisciplinarity has become a central paradigm for addressing complex socio-environmental challenges that transcend disciplinary and institutional boundaries. This article revisits the concept from the perspective of water resources management, questioning whether its increasing application has achieved the depth and transformative potential originally envisioned. A systematic review and bibliometric analysis were conducted to examine how transdisciplinarity has been conceptualized and operationalized across 61 international initiatives covering multiple governance scales and institutional contexts. The findings reveal that, although transdisciplinarity is now widely recognized in scientific and policy agendas, its implementation often remains rhetorical or fragmented. Persistent barriers include limited knowledge co-production, asymmetry between scientific and local expertise, and weak participatory mechanisms. Nonetheless, promising experiences demonstrate that when communities are engaged as co-authors of decisions, water governance becomes more legitimate, adaptive, and sustainable. By integrating empirical evidence with conceptual reflection, this study advances understanding of how ethical and methodological co-production can move transdisciplinarity from a normative paradigm toward an actionable framework for water governance