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Global Warming Affects the Pathogenesis of Important Fish Diseases in European Aquaculture
Full text linkGlobal warming remains a neglected environmental challenge for the sustainability of primary production, particularly aquaculture, which is highly susceptible to the spread of established pathogens and the induction of emerging infectious diseases under warming conditions. Over the past decade, Europe has experienced dramatically high temperatures that may impact both farmed fish and their pathogens in a largely unpredictable manner. While, in general, warming may boost the rate of disease transmission and its virulence by increasing pathogens' fitness in weakened hosts, some diseases characteristic of cooler environments may become rare. Field data is still largely fragmented, but in vitro experiments reveal that almost 28 microbial diseases in European finfish farming could be facilitated by climate warming. Innovative mitigation tools, such as fish selective breeding, epigenetic programming, the development of new vaccines, and alternative treatments, may prove essential in coping with the effects of rising water temperatures on fish diseases in Europe
Establishing the effects of Nanocellulose-based bio-inks in an advanced 3D in vitro model for cartilage tissue engineering
Full text linkTrauma, cancer or congenital conditions can lead to the loss of facial cartilage resulting in altered function and form. Tissue engineering (3D-printing) has the potential to create bespoke cartilage implants for reconstruction with biomaterials as ink carriers loaded with patient cells. There is rising interest in nanocellulose as a bio-ink candidate, but relative paucity of studies investigating an all-natural hybrid bio-ink inclusive of alginate (most common natural bio-ink material) and hyaluronic acid (HA)(native component of human extra-cellular matrix). This study aims to: i) evaluate the cytotoxic and pro-inflammatory effects of each bio-ink components individually and combined as bio-inks; ii) create an advanced 3D in vitro model for biocompatibility testing; and iii) apply the model for toxicity testing, refinement of bio-ink formulations and further model characterisation with differential gene expression analysis.Six forms of nanocellulose, alginate, HA, and two cross-linker agents were investigated for their biological impact to human chondrocyte C20A4 and dermal fibroblast HFF-1 cell lines. Material sterility was determined by microbial growth assay. Cell-line characterisation and material exposures (21 days) and cross-linker exposures (7 days) were examined for cell viability, morphology and pro-inflammatory mediators (IL-6/IL-8) release. Minimum cross-linkage time and rheologically defined gelation behaviour of bio-inks with calcium chloride (CaCl2)permitted completion of a standard operating procedure for the creation of an advanced 3D in vitro model. To mimic the implanted in vivo scenario, the in vitro model consisted of chondrocyte-encapsulated and fibroblast surface-seeded cross-linked hydrogels. RNA extraction via the spin column technique with optimisations were performed. Differential gene expression analysis was conducted using Nanostring against the nanocellulose-based bio-ink with the 3D in vitro model.All materials maintained sterility over 21 days, except for pulp-derived nanocellulose which were excluded. Material exposures (chondrocytes: nanocellulose/alginate/HA;fibroblasts: alginate/HA) showed no significant cytotoxic effects over 21 days.Enzymatically pretreated nanocellulose (ETC) displayed the lowest pro-inflammatory effects when exposed against chondrocytes, with trends of carboxymethylated(CTC)>TEMPO-mediated oxidised(TTC)>ETC on D1-7 and TTC >CTC>ETC on D14-21.CaCl2 exposure on fibroblasts demonstrated a dose- and time-dependent cytotoxicity supporting use of the lowest concentration and shortest cross-linkage time to minimise adverse cellular impact. Testing of optimised bio-inks (ETC:Alginate and ETC: Alginate:HA at 6mg/ml in media) demonstrated that nanocellulose-based bio-ink inclusive of HA was superior for chondrocyte proliferation. Heightened IL-6/IL-8 and lactate dehydrogenase release at latter timepoints indicated the need for further model development. Nanostring was successfully applied for differential gene expression analysis, which corroborated pro-inflammatory effects observed via cytokine quantification, as well as identified multiple areas of interest for further research.Overall, ETC was shown to be a promising bio-ink candidate, and when combined with alginate and HA, formed a complete bio-ink formulation specific for 3D-bioprinted cartilage constructs for reconstructive purposes. Biological and rheological testing identified optimal parameters for bio-ink and in vitro model creation, whilst RNA extraction from chondrocytes encapsulated within cross-linked bio-ink was feasible and applicable with the Nanostring technology
Enhancing rheological and ageing performance of asphalt binders using hazelnut shell biochar additives
Full text linkThis study evaluated the effect of biochars derived from European hazelnut shells as modifiers of the antioxidant, physical, and rheological properties of asphalt binders used in road construction. Two types of biochar (BH) were produced via slow pyrolysis at 300 °C (BH1) and 550 °C (BH2) with a residence time of 1 h, and were incorporated into unaged, short-term aged (RTFO), and long-term aged (PAV) asphalt binders. Phenolic compounds of the BHs were identified by liquid chromatography, while their antioxidant effect on asphalt binders was assessed using spectroscopic analyses. Physical properties (rotational viscosity, penetration, softening point, Fraass breaking point) and rheological properties (rutting parameter G*/sin(δ), Rheological Ageing Index, multiple stress creep recovery (MSCR), fatigue parameter (G*∙sin(δ), crossover temperature, and complex modulus |G*|) were measured in all ageing states. The results revealed that both BHs mitigated binder ageing, as evidenced by reductions in ageing indices and oxygenated structures. BH1’s antioxidant effect was attributed to its phenolic compounds, whereas BH2’s effect was attributed to its porous morphology, which facilitated the adsorption of volatiles. Physically, BH reduced viscosity by up to 16 % after PAV ageing, maintained penetration, and lowered the softening point, although Fraass breaking points increased due to particle stiffening. Rheologically, BH improved rutting resistance by up to 8 % during the early ageing stages. After PAV ageing, it mitigated stiffness gain, preserved viscoelastic behaviour, and reduced |G*| at low temperatures compared with the controls. Overall, recycled hazelnut shell BH enhanced the ageing resistance and thermal stability of bituminous binders through distinct mechanisms, offering a potentially viable option to extend the service life of road pavement materials
Plastic additives enrich diverse bacterial communities which show the hallmarks of plastic degradation
Full text linkPlastics contain a variety of chemical additives that enhance their performance but often pose environmental risks due to their persistence and leaching. Microbial degradation offers a promising strategy to mitigate these pollutants, yet efficient methods to identify active degraders remain limited. This project aims to combine biochemical assays with 16S rRNA amplicon sequencing to screen microbial communities for plastic additive biodegradation. Inocula from natural (Chessel Bay, Swansea Bay) and anthropogenic (Wastewater Plant, Recycling Plant) environments were enriched for 22 days, using di(2-ethylhexyl) terephthalate (DEHT) and tetradecane and compared to negative controls. We adapted high-throughput assays to measure community-level growth, death, redox, and esterase activity. DEHT yielded the highest growth, while tetradecane enhanced redox activity. 16S rRNA amplicon sequence analysis identified 957 amplicon sequence variants across 36 cultures. PERMANOVA showed that the substrate explained 39%–63% of the variance in community structure. Both additives enriched bacterial families known to degrade plastics (e.g. Nocardiaceae, which correlated with esterase activity). Other bacterial families not previously associated with plastic degradation (e.g. Vermiphiliaceae) highlight potential for plastic and additive biodegradation. These results demonstrate that diverse environmental microbiomes can metabolize ester- and alkane-based plastic additives. Our methods enable scalable screening of biodegradative communities for bioremediation applications
Rain or shine, default risks align: exploring the climate-default nexus in small and micro firms
Full text linkWe investigate the impact of escalating temperatures and heavy rainfall on the default probability of small and micro enterprises (SMiEs) in six European countries between 2005 and 2014. Our findings reveal that a one standard deviation increase (2.56∘C) in the yearly mean temperature raises a firm's default probability by 86.5 basis points. Additionally, a one standard deviation increase (2.46 mm) in the Simple Precipitation Intensity Index increases the default probability by 32.4 basis points. We argue that one channel explaining the adverse impact of climate risk on default probability is labour productivity loss. In addition, micro and financially constrained firms exhibit increased vulnerability to these risks. However, when the ultimate owners also serve as the firms' managers, they can mitigate the adverse effects of rising temperatures and heavy rainfall
Conviction: A stage play exploring attitudes and prejudices towards ex-offenders
No full textConviction is a full-length, two-act stage play set entirely within a prison classroom in a Category B men’s prison. The narrative unfolds in real time and centres on four characters:Angela, a civilian English teacher; Jimmy, a young, recidivist drug offender; Murph, a long-serving inmate convicted of murder; and Ray, a disgraced solicitor imprisoned for fraud. The play begins with light humour and classroom banter but gradually escalates into psychological unease and coercive tension, culminating in the accidental killing of Angela.Dramatically, the play explores the dynamics of authority, masculinity, survival, and institutional violence. It interrogates the rehabilitative promise of prison education, the performance of identity under surveillance, and the everyday strategies of control and resistance.The confined setting of Conviction heightens the emotional intensity, as the characters’ words and shifting tones reveal the delicate balance between power, vulnerability, and survival. The play explores the ethical complexities of an environment in which the lines between right and wrong are blurred, revealing to the audience the everyday realities of prison life. Rather than sensationalising its subject, Conviction invites reflection: How does society treat those who have served their time, and what more could we do to help them move forward without judgement
Mapping perceived service quality in tourism resorts through user-generated content
No full textThis study aims to identify the key components of service quality in Brazilian tourism resorts based on user-generated content posted on online platforms, using indicators drawn from the TOURQUAL model. The research is exploratory in nature, employing a quantitative approach. The sample comprises 82,327 textual comments published between January 2023 and January 2024. These were extracted from the TrustYou platform, which consolidates guest reviews from Google, TripAdvisor, and Booking.com. The software tools T-LAB (version 8.1) and R-Studio, with the quanteda package, were used to conduct thematic analysis, lexical mapping, and dimensionality reduction through Sammon’s mapping technique. The analysis found that perceptions relating to tangible and operational aspects were important, including factors such as food and beverage services, physical infrastructure, recreation, and cleanliness. Customer service was the most prominent perceived quality factor, involving elements such as the friendliness, technical knowledge, and attentiveness of staff
Improvement of barrier properties of recycled thermoplastic polymers by O2 and NH2 functionalized graphene nanofillers
No full textGraphene/polymer composites have a wide range of applications, such as energy storage, 3D printing, sensors, water purification, and heat dissipation materials due to their enhanced mechanical, electrical, and thermal properties. One major challenge is graphene’s tendency to aggregate due to strong Van der Waals interactions (5.9 kJ mol−1), which hinders uniform dispersion in the polymer matrix. Therefore, this study focused on improving the barrier properties of recycled polymer matrices, such as Nylon 6, Nylon 66, and polyethylene terephthalate, against moisture using chemically modified graphene nanofillers (GNPs). The nanocomposite films were prepared based on the variation of GNPs’ loadings and thicknesses. The results obtained from scanning electron microscope revealed that the addition of GNPs resulted in the formation of irregular protuberances on the fracture surface of the polymer matrices, with graphene fillers dispersed within the matrices. The water vapor transmission rate (WVTR) for samples with 0.5 mm was reduced by the addition of GNPs. The moisture barrier properties of recycled polymer matrices are improved by adding O2- and NH2- to GNPs, with interfacial interactions between the fillers and the matrices dependent on the functionalization type
The association between academic pressure and adolescent depressive symptoms and self-harm: a longitudinal, prospective study in England
Full text linkBackgroundAcademic pressure could increase the risk of adolescent depression and self-harm. However, there are few longitudinal studies of this association, and those that exist have limitations. We aimed to investigate associations between perceived levels of academic pressure and subsequent depressive symptoms and self-harm from adolescence to early adulthood. Our hypothesis was that higher levels of academic pressure would be associated with higher levels of depressive symptoms and self-harm.MethodsIn this longitudinal study, we used data from the Avon Longitudinal Study of Parents and Children (Avon, UK) that includes adolescents born in 1991–92. Our primary exposure of interest was academic pressure measured at age 15 years, using items from a school experiences questionnaire (total scores 0–9). Outcomes were depressive symptoms assessed with the Short Mood and Feelings Questionnaire at five timepoints between age 16 years and 22 years (total scores 0–26), and a self-harm questionnaire at four timepoints between age 16 years and 24 years. Analyses were linear (depressive symptoms) and logistic (self-harm in the previous year) multilevel models in samples with multiply imputed data, before and after adjustments.FindingsWe included 4714 adolescents (2725 [57·8%] female, 1989 [42·2%] male). In fully adjusted models, a 1-point increase in academic pressure at age 15 years was associated with a 0·43 (95% CI 0·36–0·51) point increase in depressive symptoms. This association was largest when depressive symptoms were assessed at age 16 years (0·53, 0·42–0·64), but remained at age 22 years (0·35, 0·23–0·47). For self-harm, in fully adjusted models, each 1-point increase in academic pressure was associated with an 8% higher odds of self-harm (adjusted odds ratio 1·08, 1·01–1·16), with no differences over time.InterpretationOur findings support the hypothesis that academic pressure is a potential modifiable risk factor for adolescent depressive symptoms, and possibly self-harm. Interventions to reduce academic pressure could be developed and evaluated
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