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Boost of trace methane photo-oxidation in the presence of water vapor via the interfacial hydrophobic effect
No full textThe study of water resistance of methane photo-oxidation catalysts is important and challenging for the removal of methane from the atmosphere. Herein, we investigate the mechanistic role of water in the photocatalytic oxidation of trace methane on ZnO decorated with various metal (Cu, Pt). We found that suppressing water dissociation at active sites mitigates hydroxyl-induced catalyst poisoning. Critical insight reveals that photo-generated holes (h+) mediate the conversion of passivating hydroxyl groups (OH*) into reactive hydroxyl radicals (•OH), simultaneously liberating active sites and promoting the reaction. In addition, temperature-dependent experiments revealed that increasing the temperature from 20 to 80 °C enhanced the methane conversion by approximately 4-fold, proving that partial desorption of water molecules from the catalyst surface releases active sites. The experimental results show that 0.5 % Pt/ZnO is about 2-fold more water resistant than 0.5 % Cu/ZnO. These findings provide valuable experience and guidance for both mechanistic understanding of water-mediated methane photooxidation and rational design of high-performance catalysts.</p
Stochastic modelling of burden of livestock diseases on domestic ruminants in Ethiopia
Full text linkThis study, carried out in 2022-2023, quantified the financial burden of disease in cattle, sheep and goats in Ethiopia for the year 2021 using the animal health loss envelope (AHLE) metric. The AHLE measures all cause disease burden, avoidable and non-avoidable, as the difference in the financial performance of a livestock production system (e.g., gross margin) comparing a scenario where animals are in an ideal state of health to the current situation. A stochastic dynamic population model (DPM) was employed to calculate the gross margin for an average farm and for the national herd under these current and ideal health scenarios. Data for parametrizing the DPM were derived from secondary sources and expert elicitation. The stochastic DPM was simulated for 10,000 iterations and results are reported as means with 95 % percentile intervals (PI). The annual AHLE per average farm was estimated at USD 1209 (95 %PI:392-2470) in cattle, USD 158 (95 %PI:66-292) in sheep and USD 416 (95 %PI:136-847) in goats. At national level, the annual AHLE in ruminants was USD 18.39 billion with USD 15.42 billion (95 % PI:12.70-18.57) in cattle, USD 1.04 billion (95 % PI:0.84-1.30) in sheep, and USD 1.93 billion (95 % PI:1.64-2.25) in goats. Morbidity losses constituted the largest component of the AHLE, exceeding 50 % across all species, while animal health expenditure represented the smallest component, accounting for less than 2 % of AHLE in all species. This high disease burden, with minimal contribution from animal health expenditure, indicates significant opportunity for improvement through investment in animal health.</p
The lexicon adapts to competing communicative pressures:Explaining patterns of word similarity
No full textCross-linguistically, lexicons tend to be more phonetically clustered than required by the phonotactics of the language; that is, words within a language are more similar to each other than they need to be. In this study, we investigate how this property evolves under the influence of competing communicative pressures: a production-side pressure to re-use more easily articulated sounds, and a comprehension-side pressure for distinctiveness of wordforms. In an exemplar-based computational model and a communication experiment using a miniature artificial language, we show that natural-language-like levels of clustering emerge from a trade-off between these pressures. With only one pressure at work, the resulting lexicons tend to inhabit an extreme region of the possible design space: production pressures alone give rise to maximally clustered lexicons, while comprehension pressures alone give rise to maximally disperse lexicons. We also test whether clustering emerges more strongly for high-frequency items, but our results lend support only to a weak relationship between frequency and clustering. Overall, this study adds to a growing body of evidence showing that mechanisms operating at the level of individual language users and individual episodes of communication can give rise to emergent structural properties of language
Microbial death in the Andes: necromass declines despite growth and carbon-use-efficiency increases with decadal soil warming
No full textThe growth and death of soil microbes are important drivers of soil carbon formation. A warming climate is predicted to affect both the production of microbial biomass and the stability of microbial residues (necromass) held in soils. However, we have very little information on how warming in tropical soils will affect these processes, and on the effect of temperature on microbial production and turnover over different time-scales. To address this, we studied temperature effects on microbial-mediated C cycling across two different time-scales, using a 20 °C mean annual temperature gradient in the Peruvian Andes (long-term effects) and decadal experimental-warming via soil translocation (11-years of temperature effects). At long-term timescales, a legacy of warmer temperatures decreased microbial carbon use efficiency (CUE), microbial biomass C, and decreased fungal and bacterial necromass concentration in soils. At decadal timescales, experimental warming increased CUE, microbial production and microbial biomass concentration (likely the result of concomitant changes in substrate availability). However, this did not translate into increased microbial necromass concentration, which generally declined with warming across all temporal scales. Together, we show that warmer temperatures over decadal (11-year) timescales affect soil microbial processes to potentially increase their C input to soil (increased CUE, microbial production, and biomass) but we find no evidence that this C became stabilized as the necromass C pool decreased. Our results indicate that warming can alter microbial community metabolism to potentially increase necromass C inputs to soil, although we find no evidence to show that this offset overall soil C loss with warming
Parental use of distraction and portioning to reduce snack intake by children with avid eating behaviour:An experimental laboratory study
Full text linkIntroduction: Children's avid eating behaviour is characterised by frequent snacking and food responsiveness. Parents need evidence-based advice on specific feeding practices, such as distraction techniques and portioning, that can be used to reduce children's intake of high energy-dense snacks. This experimental laboratory study tested the effectiveness of these feeding practices. Methods: Parents and children (3–5 years; N = 129) who were identified as having an avid or typical eating profile were recruited and randomly allocated to one of three conditions. Following a standardised meal, children's energy intake (kcal) in the absence of hunger was assessed. While children had access to a snack buffet, parents were asked to use one of the following feeding practices: (1) Distract – using distraction techniques to delay children's snack intake; (2) Portion – allowing children to have snacks from pre-portioned pots; or (3) Control – allowing children to eat the type and number of snacks that their child wanted to. Results: Children in the distraction condition consumed significantly less energy from snacks (M = 54.44 kcal, SD = 73.30) compared to children in the portion (M = 103.89 kcal, SD = 91.33, p < .001) or control condition (M = 115.92 kcal, SD = 90.55, p < .001). Energy intake in the portion and control conditions was not significantly different (p > .05). Children with avid versus typical eating profiles did not differ significantly in energy intake (p > .05). Conclusion: Parental use of distraction techniques may be effective for reducing children's intake of high energy-dense snacks and could be recommended for use to support the development of children's healthy eating. Research to examine the effectiveness of distraction in real-world settings is now needed.</p
Major element zonation following rapid heating of homogeneous glass in wire-loop experiments_full dataset
No full textData used for the publication "Major element zonation following rapid heating of homogeneous glass in wire-loop experiments". Data obtained as part of a systematic investigation of magmatic degassing process in analogue lunar magma, funded by the Leverhulme Trust through Research Project Grant RPG-2021-015, and the Carnegie Trust through PhD Scholarship award PHD01069
Controlling Tip Vortices and Cavitation through Tip Permeability for Tidal Turbin
Full text linkBlade-tip vortices can lead to wakes, cavitation and noise, and their control remains a significant challenge for tidal and wind turbines. In the present work, we propose controlling tip vortices through local permeability on a model-scale horizontal-axis turbine. The numerical investigation follows a rigorous validation and verification process. The tip permeability is modelled by including a porous zone over the blade tip, within which Darcy’s law is applied. The results demonstrate that there is an optimal range of permeability, corresponding to a non-dimensionalDarcy number, , of around 10−5, that can substantially decrease the tip vortex intensity. The revealed flow physics show that the permeable tip can effectively enlarge the vortex viscouscore radius with little change to the vortex circulation. The permeable tip treatment can increase the minimal pressure-coefficient at the vortex core by up to 63%, which significantly alleviates the cavitation risk. This approach has negligible influence on the turbine’s energy-harvesting performance because the spanwise extent of the permeable zone is only in the order of 0.1%turbine diameter. Our findings demonstrate this approach’s great promise to break the upper tip-speed ratio limit capped by cavitation for tidal turbines, contributing to developing more efficient and resilient turbines
Robust airline scheduling with turnaround under uncertainty:Towards collaborative airline scheduling
Full text linkRobust airline scheduling fosters operational resilience in aviation by producing plans that remain feasible despite ensuing disruptions. This paper analyses the airline scheduling process, including flight scheduling, fleet assignment, aircraft routing, and crew pairing. It examines how previous studies optimise these decisions and deal with the influence of the aircraft ground handling (turnaround) process, an important aspect of airport operations that is known to often create havoc in flight timetables. The analysis of the literature focuses on how to harness turnaround resilience to improve airline schedule robustness and applies a framework of variables (characteristics) to support data collection and synthesis. The variables include levels of integration of multiple planning stages, uncertainty modelling, turnaround consideration, type of robustness sought, and type of optimisation method employed. Based on our review, we propose a comprehensive airline scheduling process that incorporates turnaround planning to enhance the estimation of aircraft turn time, crew sit time, and passenger connecting time under uncertainty. More precise estimates will enable models to produce robust schedules at a lower cost (shorter buffer times). Since third-party organisations typically operate turnarounds, this planning approach needs to involve multiple autonomous decision-makers. Therefore, we encourage a collaborative robust scheduling framework to be built on existing operations research theories and industry protocols.</p
Global manta and devil ray population declines: closing policy and management gaps to reduce fisheries mortality
No full textSignificant progress has been made in advancing priority actions to conserve manta and devil rays, yet implementation and enforcement of protective measures often fall short, leaving most mobulid populations at risk of overfishing. Drawing on a literature review, fisheries databases, agency reports, and expert interviews, we assess global trends in mobulid catch and mortality. We examine both targeted and incidental catch, in small (<15m, ‘SV’) and large (>15m, ‘LV’) vessel fisheries to identify hotspots with the highest risk of fisheries-related mortality and population decline. We estimate global fisheries catch 264,520 (184,407 – 344,987) mobulids per year, with SV fisheries accounting for 87% of global mortality. The highest-risk hotspots, based on mortality and declines, are located in India, Indonesia, Sri Lanka, Peru, and Myanmar. Mobulid retention is driven by demand, with higher mortality rates observed in countries exporting gill plates, and to a lesser extent, in those trading meat domestically or internationally. We recommend urgent implementation and enforcement of mobulid listings under the Convention on International Trade in Endangered Wild Flora and Fauna (CITES), the Convention on the Conservation of Migratory Species of Wild Animals (CMS), and national protective measures, including (i) uplisting mobulids to CITES Appendix I, (ii) full legislative protection for all mobulid species in high-risk fishing nations to reduce demand, (iii) avoiding fishing in critical habitats through permanent or temporary targeted area closures, or management, (iv) limiting drift gillnet effort, and (v) involving fishers in management decisions and implementation
Investigating TRPM3 Modulation and Cyst Reversibility in Ex Vivo and Organoid Models of Autosomal Dominant Polycystic Kidney Disease (ADPKD)
No full textAutosomal dominant polycystic kidney disease (ADPKD) is the most common hereditary kidney disease, affecting approximately 1 in 1000 live births. It is characterised by multiple fluid-filled cysts in renal tubules. ADPKD is associated with mutations in the PKD1 and PKD2 genes, which encode the proteins polycystin 1 (PC1) and polycystin 2 (PC2). PC1 is a transmembrane protein that acts as a mechano-sensor, while PC2 is a non-selective cation channel that belongs to the transient receptor potential (TRP) superfamily. PC1 and PC2 form a heterodimer complex in the primary cilium, crucial for regulating intracellular calcium levels. Recent research suggests that TRPM3, another TRP family member, is necessary for PC2's ciliary function. Therefore, I analysed the impact of TRPM3 activators (nifedipine and CIM0216) and inhibitors (isosakuranetin, primidone, and diclofenac) on cyst formation in cultured E12.5 mouse kidneys which were exposed to various concentrations of forskolin, a compound known to induce cyst formation in kidney cultures. The results indicated that cyst formation occurred at lower forskolin concentrations in kidney rudiments treated with TRPM3 antagonists. In contrast, TRPM3 agonists significantly reduced cyst formation, especially at high forskolin concentrations, compared to kidneys treated with forskolin alone. Among the TRPM3 agonists tested, nifedipine—an FDA-approved antihypertensive drug—showed potential as a therapeutic for ADPKD. Isosakuranetin was the TRPM3 antagonist that most significantly increased forskolin sensitivity. I generated a drug-induced PKD model by treating mouse kidney rudiments with isosakuranetin and forskolin to analyse cyst reversibility. Cysts in my PKD model originated from proximal tubules and showed disrupted apical-basal polarity. Upon isosakuranetin and forskolin withdrawal, cysts shrank and eventually disappeared with no detectable cell death. I showed that siRNA-based downregulation was not a useful technique for designing a reversible cyst-forming organoid model, at least in my experimental conditions. To test whether similar results in cyst reversibility could be achieved in mutant human systems, I developed a CRISPR/Cas13b-based reversible gene downregulation system for future studies. This tool has the potential for the analysis of cyst regression in human organoid studies by inducing cyst formation through controlled downregulation of PKD1 or PKD2 genes, followed by gene re-expression. Overall, the study suggests that TRPM3 could be a viable target for ADPKD treatment, and nifedipine may be a promising therapeutic option. The findings also provide detailed findings into cyst regression in an early developmental stage. However, it should be noted that all results obtained in these studies were from ex vivo mouse kidney rudiments. To obtain more reliable results, the data here should be confirmed in human ADPKD models. In this context, nifedipine can be tested in ADPKD patient-derived organoids or PKD1 or PKD2 mutant human organoid models
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