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High fidelity CFD/CSD method for rotor blade optimization
No full textThis paper demonstrates a framework for using high-fidelity methods to design rotor blades. An initial rectangular blade is optimised with respect to a generalised blade surface parameterisation, which includes variations in twist, chord, sweep and anhedral. Particular focus is placed on coupling aeroelasticity with the adjoint optimisation and trimming methods at desired flight conditions. Conclusions are drawn on the new design’s effectiveness and the framework’s efficiency to obtain it. The obtained design featured a twist distribution balancing hover and forward flight performance, with a tip design needed to alleviate adverse effects in forward flight. Prominent features include forward and aft tip sweeps with a small reduction in chord distribution
Trends in socioeconomic inequalities of dental caries experience among 12-year-olds in Chile: an ecological cohort study
No full textIntroduction:
Socioeconomic inequalities in childhood dental caries remain a major public health concern, even in countries with declining overall prevalence. Chile provides a unique setting to examine these inequalities nationally and assess the potential mitigating role of systemic fluoride delivery programmes.
Methods:
This ecological cohort study analysed 1,261,690 dental examinations of 12-year-olds across 325 Chilean municipalities from 2009 to 2023, representing 99.8% of eligible national records. Caries prevalence was modelled against area socioeconomic deprivation (IDSE deciles), adjusting for rurality and systemic fluoride delivery programmes, and weighting for number of total examinations by municipality/year. Inequality metrics included Absolute Rate Difference (ARD), Slope Index of Inequality (SII), and Relative Index of Inequality (RII).
Results:
A strong and persistent socioeconomic gradient was observed: adolescents in the most deprived municipalities had a 17 percentage-point higher caries prevalence than those in the least deprived (β = -0.17, 95% CI: -0.20, -0.14). This gradient followed a dose-response pattern and was confirmed by summary measures (ARD = 0.151; RRR = 1.234). Temporal analysis revealed peak inequality pre-pandemic (SII = 0.17, 95% CI: -0.20, -0.14), followed by a steady decline post-2018, reaching non-significant levels by 2023 (SII = 0.04, 95% CI: -0.15, 0.06). Fluoridation programmes modestly attenuated the deprivation gradient by 24% (β = -0.13), though they explained limited variance (ΔR² = 0.04).
Conclusion:
Socioeconomic inequalities in dental caries among Chilean adolescents remain substantial, despite national declines in prevalence. While systemic fluoridation contributes to modest reductions in inequality, structural determinants are the primary drivers of persistent inequalities
Cardiovascular risk as a moderator of the relationship between plasma Alzheimer disease biomarkers and cognitive status
Get PDFBackground:
Plasma biomarkers may aid Alzheimer disease (AD) diagnosis and prognosis. Cardiovascular risk contributes to cognitive decline in AD, but whether it modifies the relationship between plasma biomarkers and cognitive status has not been assessed in a large multisite cohort. We aimed to explore if cardiovascular risk moderates plasma AD biomarkers’ relationship with cognitive status.
Methods:
We included cognitively normal (n=301) participants and participants with mild cognitive impairment or probable AD (n=444) from the Bio‐Hermes‐001 study. Cardiovascular risk was quantified using the Atherosclerotic Cardiovascular Disease risk calculator. Logistic regression analyzed associations of cardiovascular risk and plasma biomarkers (amyloid beta 42/amyloid beta 40, phosphorylated tau [p‐tau]181, p‐tau217, apoE4 [apolipoprotein E]) with cognitive status. Moderation by cardiovascular risk was tested in each model.
Results:
We included 745 participants (mean age=72.3 years; 423 [56.8%] female). Plasma biomarkers and cardiovascular risk were independently associated with cognitive status across models; the strongest association was with p‐tau217 (odds ratio [OR], 2.33 [95% CI, 1.89–2.9]; P<0.001). Cardiovascular risk moderated only the relationships of p‐tau181 and p‐tau217 with cognitive status (P<0.05).
Conclusions:
Plasma AD biomarkers and cardiovascular risk were independently associated with cognitive status, with cardiovascular risk moderating the p‐tau181 and p‐tau217 cognitive status relationships. If certain plasma biomarkers and cardiovascular risk independently contribute to dementia risk, cardiovascular risk assessment should complement other biomarker evaluations in cognitive screening. Results should be interpreted with caution as associations might be primarily driven by age and sex. Future research including education and genetic risk is needed to clarify the studied relationships
Structural and functional characterization of chemically modified antisense oligonucleotides targeting miR-214-3p in endothelial cells
Get PDFMiR-214-3p is a multifunctional regulator involved in oxidative stress, vascular inflammation, and endothelial nitric oxide synthase (eNOS)-dependent vasodilation. Its aberrant expression contributes to endothelial dysfunction and cardiovascular pathology, making it an attractive therapeutic target. Here, we report the design and evaluation of a panel of eight antisense oligonucleotides (ASOs) complementary to the miR-214-3p guide strand and incorporating locked nucleic acid (LNA) or 2′-O-methoxyethyl (MOE) modifications. Comprehensive macromolecular and physicochemical analyses, including melting temperature (Tm) predictions, molecular dynamics (MD) simulations, circular dichroism (CD) thermal stability assays, and nuclease degradation studies, demonstrated that LNA and MOE modifications markedly enhance duplex stability and nuclease resistance compared with the commercial miRCURY LNA miR-214 inhibitor. Among the tested designs, ASO-60 displayed the most favorable properties, combining superior thermodynamic stability with strong target engagement. Functional assays in human umbilical vein endothelial cells (HUVECs) further confirmed that ASO-60 effectively relieved miR-214-mediated repression of eNOS, as well as other key endothelial genes, outperforming the reference inhibitor at submicromolar concentrations. These findings support ASO-60 as a promising lead for further development and highlight how macromolecular characterization of chemically tailored oligonucleotides can bridge structural optimization with translational potential in restoring endothelial function and addressing cardiovascular disease
Status assessments for two endangered populations of vendace (Coregonus albula) and evidence that their abundance is modulated by percid fishes
No full textThe study of low-latitude populations can inform our understanding of how cold-adapted species might respond to environmental change. The vendace (Coregonus albula) is a lacustrine fish that is distributed across northern Europe. In the UK, there are two extant native vendace populations. These populations are at the south-western edge of the species' global distribution and both are exposed to a range of pressures including eutrophication, rising water temperatures and introduced fishes. These populations were assessed in 2024 using a combination of quantitative hydroacoustics and targeted gill netting. These data were then placed in the context of population assessments spanning the preceding three decades. Finally, the time series of population assessments was analysed to identify factors that were associated with low abundances of vendace. In both lakes, the abundance of post-juvenile vendace was higher in 2024 than expectations derived from a reference baseline. The balanced age structure of the vendace captured by gill net indicated regular recruitment to the post-juvenile age groups and there was no evidence that the lakes lacked the deep water refugia that vendace require to avoid thermal stress. High abundances of native perch (Perca fluviatilis) and introduced ruffe (Gymnocephalus cernua) in the natal years of the dominant post-juvenile vendace age groups were associated with markedly low vendace population sizes. As ruffe are not native to the studied lakes, this demonstrates one of the risks associated with the translocation of fish. However, despite the threats they face, the UK's two endangered populations of vendace appear to be persisting
Seasonal decline in mitochondrial plasticity in the three-spined stickleback
Get PDFMitochondrial plasticity enables ectothermic animals to maintain performance under changing thermal conditions, but whether this ability declines through adulthood is unknown. We explored changes in mitochondrial plasticity in the three-spined stickleback (Gasterosteus aculeatus), a temperate fish that in many populations has a single breeding season over which it produces multiple clutches and then dies. Wild-caught fish were exposed to one of three thermal regimes: remaining at 12°C, switching to constant warm (21°C) or diel cycling (12–21°C) for three weeks at either the beginning or end of the season. We quantified both phosphorylating and non-ATP-producing (OXPHOS and LEAK) respiration in isolated muscle mitochondria and oxidative control efficiency (OxCE). Early in the breeding season, young fish responded to elevated temperatures by adjusting both their capacity for ATP production and non-ATP-production respiration, but this mitochondrial plasticity declined over the season. OxCE was unaffected by time of season or temperature treatment. Changing body condition was unrelated to mitochondrial function. Our findings indicate that mitochondrial plasticity declines across adult life, potentially limiting thermal resilience in older individuals, the first time this has been reported in an ectotherm. This highlights the need to account for age-related physiological changes in capacity when predicting species’ responses to environmental change
National-scale river water quality in the Philippines: establishing baselines in a mineralised megadiverse nation
Get PDFMining underpins the global economy, is crucial to achieving net-zero targets yet can cause significant degradation of river health. Critical to managing this risk are national river monitoring programmes ideally incorporating pre-mining baseline water quality data to evaluate the impacts of mining and the success of mine site rehabilitation. We obtained metal(loid) flux, concentration, and bioavailability baseline data across the Philippines, a country with limited environmental datasets, globally significant biodiversity, and considerable mineral wealth, to establish nationwide benchmarks of water quality prior to an industrialisation of mining operations. Through sampling 10 major catchments, we show the Philippines contributes proportionally large volumes of metal(loid)s to the oceans (3 % Co, 1.7 % Ni, 1.2 % Cu, 0.6 % Cr). These large fluxes are not solely from mining-impacted catchments but also from mineralised catchments with no large-scale mining. This suggests that an apportionment approach, where contaminant contributions are allocated to baseline and anthropogenic sources, would be beneficial to catchment managers and help identify and prioritise remedial interventions. Additionally, CDGT (bioavailable) metal(loid) concentrations varied substantially across the Philippines, demonstrating the need for water quality guidelines based on ecologically-relevant metal(loid) concentrations. This study establishes the first nationwide ground-truthed baselines of hydrology and water quality in the Philippines, providing a reference point for future management and a statement of current condition. Beyond the Philippines, our monitoring approach can be adopted in other mineralised nations so that the future impacts of mining and the efficacy of sustainable mining approaches can be effectively monitored and reported on
South Asian Muslim women’s experiences of divorce in Scotland
No full textThis article provides an in-depth exploration of the experiences of eight Muslim women who were divorced or sought to be divorced in Scotland. Scotland is distinct within the UK in facilitating the civil registration of marriage by a religious celebrant, but divorce may still require separate legal and religious procedures. We found that participants were disempowered when husbands utilised Islamic processes to end marriages, leaving women without financial support and to initiate legal proceedings. Scottish family law creates a new set of challenges, especially when children are involved and/or finances have to be agreed upon. Civil and Islamic processes were weaponised to control women’s marital and financial status, a phenomenon that can be understood through a gendered lens and within the context of domestic abuse and coercive control. Further research is needed to understand how far the experiences here are representative within and outside the Muslim community in Scotland
Grower-in-the-loop interactive reinforcement learning for greenhouse climate control
Get PDFClimate control is crucial for greenhouse production as it directly affects crop growth and resource use. Reinforcement learning (RL) has received increasing attention in this field, but still faces challenges, including limited training efficiency and high reliance on initial learning conditions. Interactive RL, which integrates human (grower) input with the RL agent’s learning, offers a potential solution to overcome these challenges. However, interactive RL has not yet been applied to greenhouse climate control. Furthermore, human input is hardly perfect due to the complexity of climate control. The performance of interactive RL may also be limited by imperfect input. Therefore, this paper aims to explore the possibility and performance of applying interactive RL with imperfect inputs into greenhouse climate control, by: (1) developing three representative interactive RL algorithms tailored for greenhouse climate control (reward shaping, policy shaping and control sharing); (2) analyzing how input characteristics are often contradicting, and how the trade-offs between them make grower’s inputs difficult to perfect; (3) proposing a neural network-based approach to enhance the robustness of interactive RL agents under limited input availability; (4) conducting a comprehensive evaluation of the three interactive RL algorithms with imperfect inputs in a simulated greenhouse environment. The demonstration shows that interactive RL incorporating imperfect grower inputs has the potential to improve the performance of the RL agent. Interactive RL algorithms that influence action selection, such as policy shaping and control sharing, perform better when dealing with imperfect inputs, achieving 8.4% and 6.8% improvement in profit, respectively. In contrast, reward shaping, an algorithm that manipulates the reward function, is sensitive to imperfect inputs and leads to a 9.4% decrease in profit. This highlights the importance of selecting an appropriate mechanism when incorporating imperfect inputs
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