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New level resolved ground and excited state Pb III, IV, V, and VI photoionization cross-sections for heavy metal subdwarf modelling
No full textHigh abundances of various lead (Pb) species have been identified in the spectra of many asymptotic giant branch stars and O- and B-type subdwarfs (sdO/B). Additional atomic data relating to Pb, and in particular photoionization cross-sections, are needed to allow a greater understanding of the origin of these observed Pb abundances, and hence discern the evolutionary pathway of these stars. We have calculated level-resolved photoionization cross-sections for Pb iii, iv, v, and vi. Four new target structures have been developed with the General Relativistic Atomic Structure Package (grasp0), whose corresponding energy levels, Einstein A-coefficients, and oscillator strengths have been found to be in good agreement with previous experimental and theoretical sources. The photoionization cross-sections calculated using the Dirac Atomic R-matrix Codes (darc) are available in topbase format, and follow the trends expected for an isonuclear series. These new Pb data sets will now allow for the modelling of Pb abundances and line opacities under non-local thermodynamic equilibrium (non-LTE) conditions. Using the helium-rich hot subdwarf EC 22536–5304 as a test case, we show that there are noticeable differences in the Pb line profiles across the ultraviolet and optical wavelength regions under LTE and non-LTE conditions. There is both depletion and enrichment of individual Pb species. This highlights the importance of applying non-LTE conditions when modelling EC 22536–5304, as well as other O/B-type stars.<br/
Dual-functional La<sub>2</sub>NiO<sub>4</sub> impregnation for enhancement of catalytic activity and microstructure in SOEC fuel electrodes
No full textAchieving high efficiency and long-term durability in solid oxide electrolysis cells (SOECs) requires innovative electrode engineering. In this study, we report a simple and scalable impregnation strategy to enhance the performance and stability of SOECs by modifying the conventional Ni-YSZ fuel electrode with La2NiO4. Under operating conditions, La2NiO4 undergoes in-situ decomposition, forming a nanocomposite of Ni nanoparticles embedded within La(OH)3 substrate. This unique structure provides abundant catalytic sites for H2O dissociation and suppresses Ni coarsening, thereby ensuring stable electrochemical performance. The impregnated electrode delivered a high current density of −1.36 A cm−2 at 1.3 V and 750 °C, while exhibiting significantly enhanced stability with a low degradation rate of only 0.25 mV h−1 over 200 h, significantly outperforming the unmodified electrode counterpart. Electrochemical and microstructural analyses further confirmed reduced polarization resistance and excellent microstructural robustness. These findings highlight the promise of this impregnation approach for developing high-performance, durable SOEC electrodes, advancing sustainable hydrogen production technologies.<br/
Management of alien bird impacts does not reflect their severity
No full textBiological invasions can harm biodiversity – indeed, they are a principal cause of native species extinctions (Bellard et al. 2016. Alien species as a driver of recent extinctions. Biol. Lett. 12:20150623). Biological invasions occur worldwide – whilst some of their impacts are managed, others are not. Identifying drivers of management actions may reveal why some impacts remain unmanaged, informing strategies to improve management consistency. We identified factors that influence actions to protect native animals from the biodiversity impacts of alien birds. We reviewed literature to identify impacts, categorising them as unmanaged or managed (irrespective of management success). For each impact, we collected data on variables hypothesised to influence management, including characteristics of affected native species (e.g., endemism) and alien species (e.g., years resident as an alien); characteristics of impacts (e.g., their severity – how harmful they are to native species, as measured using a published framework); and characteristics of the environment (e.g., human population density). We used binomial mixed effects models to identify associations between variables and management. Intuitively, actions to manage alien bird impacts tend to focus on the protection of endemic species. However, they do not focus on the most severe impacts, nor the most threatened native species. Indeed, feasibility influences actions, whereby long-established alien bird populations with damaging biodiversity impacts remain unmanaged, most likely because these long-established populations tend to be large and widespread and hence are considered too difficult or costly to manage. Timely interventions are crucial to prevent the damaging biodiversity impacts of biological invasions from becoming unmanageable
Transplantation of mesenchymal stromal cell-derived mitochondria alleviates endothelial dysfunction in pre-clinical models of acute respiratory distress syndrome
No full textBackgroundPulmonary endothelial dysfunction with increased capillary permeability is a key aspect in the pathogenesis of acute respiratory distress syndrome (ARDS). It has been demonstrated that mesenchymal stromal cells (MSC) can modulate host cells through mitochondrial transfer. Although mitochondrial transplantation is a promising treatment strategy for conditions underpinned by mitochondrial dysfunction, its therapeutic potential in ARDS has not been sufficiently investigated. Herein, we tested the potential of MSC mitochondrial transplantation to restore functionality of the pulmonary endothelium in pre-clinical models of ARDS.MethodsMitochondria (mt) derived from human bone-marrow MSC were isolated and immediately used for transplantation to primary human pulmonary microvascular endothelial cells (HPMEC) in the presence of Escherichia coli lipopolysaccharide (LPS) or plasma samples from ARDS patients classified into hypo- and hyper-inflammatory phenotypes. Mitochondrial function, inflammatory status, and barrier integrity of HPMEC were assessed at 24 h. LPS- challenged mice were treated with MSC-mt intravenously, and the severity of lung injury and inflammatory response were evaluated.ResultsExposure to LPS or ARDS plasma induced endothelial hyperpermeability associated with mitochondrial dysfunction. MSC-mt were readily internalized by HPMEC without cytotoxicity or inflammatory response, mitigating mitochondrial dysfunction and restoring barrier integrity. In vivo, administration of MSC-mt alleviated lung injury, reduced inflammatory cell infiltration in the alveoli and increased VE-cadherin mRNA levels in the lung tissue, indicating restoration of the alveolar-capillary barrier integrity.ConclusionThis study demonstrated MSC mitochondrial transplantation as a promising therapeutic approach for treatment of endothelial dysfunction in the context of acute inflammation. Further exploration of mitochondrial transplantation in ARDS is warranted.<br/
Mould-free microneedles in a single step: 3D printing with photopolymer resins for transdermal delivery
No full textDigital light processing (DLP) 3D printing has emerged as a rapid alternative to la-bour intensive micro moulding for producing microneedle (MN) arrays, yet its use in biodegradable, dissolving MNs has been limited by proprietary, non degradable resins. The current study proposed an innovative, biocompatible PEGDA-vinyl pyrrolidone photo-resin with lithium phenyl(2,4,6 trimethylbenzoyl) phosphinate initiator, which systematically optimises its rheology and photo-reactivity for DLP printing. The resin viscosity, cure kinetics and spectral signatures were characterised, and a 40 % PEGDA up-to 100 % VP blend with 0.4 % initiator was identified as providing rapid photopol-ymerisation, low shrinkage and complete vinyl conversion. Using a desktop DLP plat-form, 6 × 6 MN patches were printed in a single step without moulds and analysed by optical and scanning electron microscopy. The printed MNs reproduced CAD dimen-sions with <3 % deviation, achieving a height of 1.40 ± 0.02 mm and a base thickness of 1.00 ± 0.01 mm, and showed a tip radius consistent with sharp penetration. Compression testing measured an array force of 32 N, corresponding to ~0.9 N per needle, exceeding the 0.2 N threshold for skin insertion. FTIR and 1H NMR confirmed near quantitative crosslinking, thermogravimetric and differential scanning calorimetry indicated stabil-ity at ambient conditions, and dissolution studies showed complete needle dissolution. These results demonstrate that pixel aware DLP printing of an optimised PEGDA/VP resin yields geometrically precise, mechanically robust dissolving MNs in a single step, addressing the limitations of micro moulding and paving the way for customisable, on demand transdermal delivery of active molecules and biologics
The role of the pulmonary microenvironment in driving Systemic Sclerosis (SSc) to Systemic Sclerosis-Interstitial Lung Disease (SSc-ILD) transition
No full textOBJECTIVE: A common complication in systemic sclerosis (SSc) is the development of SSc-associated interstitial lung disease (SSc-ILD), which has poor prognosis and high mortality rates. The pulmonary microenvironment may include mediators involved in disease pathogenesis that could be targets for new therapies to reduce SSc-to-SSc-ILD transition. Here, we aimed to identify soluble mediators in bronchoalveolar lavage fluid (BALF) that would differentiate SSc-ILD from SSc only patients through a systematic review.METHODS: Using a pre-registered study protocol, two databases (Web of Science, PubMed) were screened for publications between 2000-2024 in adult patients (keywords "Systemic sclerosis AND biomarker AND (lung lavage OR bronchoalveolar lavage)"). Mediators were meta-analysed (RevMan) and functionally enriched pathways identified (STRING-DB/G:Profiler).RESULTS: Screening identified 20 (out of 82) publications for inclusion into the systematic review; with qualitative synthesis (n=12) and meta-analyses (n=5). 30 different mediators were identified, 17 were available for SSc versus SSc-ILD comparison. Mediators showed a strong interconnectedness and were clustered into 3 groups: those released from tertiary granules (predominately extracellular matrix remodelling function), with chemokine receptor binding or antioxidant function.CONCLUSION: Due to the limited number of studies, we were unable to perform a meta-analysis on mediators between SSc and SSc-ILD, highlighting the need for further studies. However, our review strongly highlights the involvement of the pulmonary epithelium in SSc-ILD, contributing to positive feedback between injured epithelial cells and fibroblast activation/fibrosis. Further research into the role of the epithelium is needed to identify novel mechanisms leading to SSc-ILD that could serve as novel pharmacological targets.</p
Perspective on sustainable strategies for integrating catalytic CO<sub>2</sub> valorization in industrial processes: advances, challenges, and opportunities
No full textThis perspective paper explores the pivotal intersection of sustainability, industrial processes, and catalytic CO2 valorization. Industrial activities contribute significantly to greenhouse gas emissions, necessitating a shift towards positioning CO2 as a valuable resource rather than a pollutant. Catalytic valorization not only mitigates emissions but also fosters a circular economy by using CO2 as carbon pool for fuels and chemical synthesis. This perspective highlights recent advances, emerging technologies, and economic considerations in CO2 valorization, emphasizing interdisciplinary collaboration. It evaluates economic viability, identifies challenges, and underscores the importance of infrastructure, market acceptance, and regulatory frameworks. As industries pursue sustainability, CO2 valorization offers a transformative solution for a greener industrial landscape