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Different roads to the brain: A brief overview of divergent pathways and convergent mechanisms in amoebic neuroinvasion
No full textFree-living amoebae such as Acanthamoeba spp., Balamuthia mandrillaris, and Naegleria fowleri are opportunistic protists capable of causing devastating infections of the central nervous system. Although these organisms differ in ecology, morphology, and clinical progression, they converge on shared strategies that enable adhesion, immune evasion, and neuroinvasion. Here, we briefly present a comparative analysis of their routes of entry, molecular determinants, and neuropathogenic mechanisms with an eye to understand parallel and divergent pathways. A complete understanding of shared and distinct mechanisms can inform translational advances, including organoid-based modelling, multi-omics biomarker discovery, and therapeutic targeting of conserved host-pathogen signalling pathways
Allelic diversity of the Zymoseptoria tritici effector Zt-11 leads to the loss of interactions with small, secreted proteins from wheat
No full textPathogen secreted effector proteins play a key role in host-pathogen interactions, however the evolutionary and structural mechanisms underlying their diversification remain poorly understood. Previously, Zt-11 a Zymoseptoria tritici pathogen effector was found to interact with small, secreted proteins from wheat (TaSRTRG6, TaSSP6 and TaSSP7). Deletion of Zt-11 delayed Septoria tritici blotch (STB) disease development in wheat. Here, we investigate the diversity of Zt-11 in 168 field isolates which revealed high allelic diversity in Zt-11, three distinct Zt-11 haplotype groups and signatures of positive selection. Structural predictions of these isoforms and the wheat host interacting protein TaSRTRG6, exhibit high structural confidence (pLDDT >80). Whereas the wheat interactors TaSSP6 and TaSSP7 are intrinsically disordered proteins with no reliable structural model. Molecular docking and yeast two-hybrid assays revealed haplotype-specific binding between Zt-11 and TaSRTRG6, with some isoforms showing loss of interaction in vivo. Finally, I1:H1 which no longer interact with small, secreted wheat proteins (TaSRTRG6, TaSSP6 and TaSSP7) also displayed increased disease symptoms during wheat infection assays. Together these findings suggest that Zt-11 undergoes evolution through positive selection and structural adaptation enabling evasion from wheat host small, secreted proteins
Comparison of international wind loading codes with a proposed Computational Fluid Dynamics framework considering the slenderness of buildings
No full textThis study compares the latest editions of five international wind loading codes -namely, the American code (ASCE 7–22), the Japanese code (AIJ-2019), the Australian/New Zealand code (AS/NZS 1170.2:2021), the European code (EN 1991-1-4:2018), and the Canadian code (NBCC 2020)- against a proposed Computational Fluid Dynamics (CFD) framework. The comparison is based on 12 isolated square buildings situated in open terrain, with height-to-plan-dimension ratios (H/B) ranging from 1 to 12. The objective is to classify each code according to the H/B ratio, identify its strengths and limitations, and highlight the scenarios where wind tunnel testing becomes essential. The influence of building natural frequency is also examined. Numerical results reveal that, for along-wind loads, ASCE 7–22 aligns well with CFD predictions for H/B ≤ 6, when the directionality factor is not considered. AIJ 2019 and NBCC 2020 show good agreement for H/B ≤ 8, AS/NZS 1170.2:2021 for H/B ≤ 5, and EN 1991-1-4:2018 for H/B ≥ 6. For across-wind base moments, AS/NZS 1170.2:2021 matches the CFD results well at H/B ratios of 3 and 4. In terms of acceleration, EN 1991-1-4:2018 provides the best match for along-wind acceleration, while NBCC 2020 performs best for cross-wind acceleration. Furthermore, the findings confirm the necessity of employing wind tunnel testing or a CFD-based approach when the building exceeds an H/B ratio of 4, as across-wind effects become dominant beyond this threshold
A review of the ground seismic vibrations induced by wind-turbines: controls, issues and opportunities
No full textTo meet our Net Zero commitments, the past decade has seen a dramatic increase in wind power, with hundreds of thousands of wind turbines already in place. Many studies have focused on the environmental impact of windfarms; however, wind turbine-induced ground seismic vibrations have received less attention. Prior seismic observations near wind turbines show apparently contradictory spatio-temporal noise patterns and complex relationships to operational parameters. Here, we investigate these contradictions, categorizing seismic observations from wind farms worldwide, and explain the causes for this variation. We link the ground seismic response to the fundamentals of wind, the structural response of wind turbines, and the interactions of their foundations with variable geology. We summarise these approaches and discuss potential implementation in noise management, alongside noise suppression technologies. We finally explore the use of wind turbine noise as a seismic source to potentially monitor the structural health of wind turbine structures, and the subsurface. The latter is highly relevant to measurement, monitoring and verification of CO2 and H2 storage, where cost-effective and long-term monitoring solutions are necessary
CFD investigation of indoor airflow and heat removal during night cooling with ceiling and attic ventilation in a residential building
No full textThis paper investigates the cooling potential of a perforated ceiling as part of a night-time ventilation technique for residential buildings in tropical climates. 3D steady Reynolds-averaged Navier-Stokes computational fluid dynamics simulations were carried out under non-isothermal conditions (wind and buoyancy-driven ventilation) for an isolated realistic single-story residential building with internal partitions and a pitched roof. Three different building ventilation configurations were assessed, i.e. cross-ventilation through window openings on the windward and leeward walls (C1), configuration C1 but with a perforated ceiling and attic ventilation (C2), single-sided ventilation through the windward window opening combined with a perforated ceiling and attic ventilation (C3). The results show that C2 performs better than C1 and C3, as it allows the most efficient heat removal from the occupied zone, resulting in a reduction of the volume-average mean air temperature within the rooms. Configuration C2 resulted in a 98% higher heat removal effectiveness (HRE) and a 20% higher air exchange rate (ACH) than the reference case (C1). Decreasing the porosity of the perforated ceiling for C2, from φ = 40% to φ = 33%, resulted in a reduction of HRE and ACH of 32% and 7%, respectively. Furthermore, different approach-flow angles (i.e. α = -60°; α = -30°; α = 0°; α = 30°; α = 60°) did not significantly affect HRE and ACH within the unpartitioned side of the building (Room 1 (R1)), while a substantial effect was found for the partitioned side (R2/R3). Overall, C2 outperforms C1 and C3 with respect to heat removal
UHS Microfluidic Investigation of Hydrogen-Methane Mixtures at 58.6 bar and 20–50 °C
No full textHydrogen storage in depleted gas reservoirs has gained attention as a large-scale option for intermittent green energy. Few experimental studies have investigated the influence of its native natural gas on the storage process. We investigate the influence of methane on UHS through microfluidic experiments with pre-blended and port-injection mixtures at 58.6 bar and 20–50 °C. Our drainage results indicate a positive correlation between front stability and capillary number. A wider range of pores is invaded with increasing methane content. In-situ mixing exerts a negative effect on storage capacity (as high as 13 %) and flow connectivity. Conversely, a higher withdrawal efficiency is observed for hydrogen, with one-third of the remaining ganglia occupying pore corners and parts of pores. Presence of methane in the mixtures increases the percentage of multiple pore-spanning ganglia from 1.6 % to 23–25 % at the end of imbibition. While the presence of methane can enhance connectivity, the process of in-situ mixing may reduce storage capacity, indicating a complex effect on the overall UHS process which required further investigation especially over higher-pressure conditions
Techno-Enviro-Economic Assessment of Long-Term Strategic Capacity Expansion for Dubai’s Clean Energy Future Using PLEXOS
No full textWith global energy systems shifting toward sustainable solutions, Dubai faces the challenge of meeting rising energy needs while minimizing environmental impacts. This study explores long-term (LT) strategic planning for Dubai’s power sector through a techno-environmental–economic lens. Using PLEXOS® modelling software (Version 9.20.0001) and official data from Dubai’s main utility provider, a comprehensive model examines medium- and LT energy pathways. The analysis identifies solar photovoltaic (PV) technology as central to achieving Dubai’s goal of 100% clean energy by 2050. It also highlights the need to cut emissions from natural gas (NG) infrastructure, targeting a goal of 14.5% retirement of NG energy generation capacities by the mid-century. Achieving zero-emission goals will require complementary technologies such as carbon capture (CC), nuclear energy, and energy storage as part of a broader decarbonization strategy. This study further assesses the economic effects of climate policy, showing that moderate carbon pricing could increase the Levelized Cost of Energy (LCOE) by an average of 6% across the forecast horizon. These findings offer valuable guidance for decision-makers and stakeholders, particularly the Dubai Electricity and Water Authority (DEWA), in advancing a carbon-neutral energy system. By 2050, Dubai’s total installed generation capacity is projected to reach 53.3 GW, reflecting the scale of transformation needed to meet its clean energy ambitions
Epanechnikov Nonparametric Kernel Density Estimation Based Feature-Learning in Respiratory Disease Chest X-Ray Images
No full textThis study presents a novel method for diagnosing respiratory diseases using image data. It combines Epanechnikov’s non-parametric kernel density estimation (EKDE) with a bimodal logistic regression classifier in a statistical-model-based learning scheme. EKDE’s flexibility in modeling data distributions without assuming specific shapes and its adaptability to pixel intensity variations make it valuable for extracting key features from medical images. The method was tested on 13808 randomly selected chest X-rays from the COVID-19 Radiography Dataset, achieved an accuracy of 70.14%, a sensitivity of 59.26%, and a specificity of 74.18%, demonstrating moderate performance in detecting respiratory disease while showing room for improvement in sensitivity. While clinical expertise remains essential for further refining the model, this study highlights the potential of EKDE-based approaches to enhance diagnostic accuracy and reliability in medical imaging.</p
Isofrequency spin-wave imaging using color center magnetometry for magnon spintronics
No full textMagnon spintronics aims to harness spin waves in magnetic films for information technologies. Color center magnetometry is a promising tool for imaging spin waves, using electronic spins associated with atomic defects in solid-state materials as sensors. However, two main limitations persist: the magnetic fields required for spin-wave control detune the sensor-spin detection frequency, and this frequency is further restricted by the color center nature. Here, we overcome these limitations by decoupling the sensor spins from the spin-wave control fields -selecting color centers with intrinsic anisotropy axes orthogonal to the film magnetization- and by using color centers in diamond and hexagonal boron nitride to operate at complementary frequencies. We demonstrate isofrequency imaging of field-controlled spin waves in a magnetic half-plane and show how intrinsic magnetic anisotropies trigger bistable spin textures that govern spin-wave transport at device edges. Our results establish color center magnetometry as a versatile tool for advancing spin-wave technologies. [Abstract copyright: © 2025. The Author(s).
Sex and physicochemistry modulate the acute toxicity of PAHs in the tropical amphipod model, Parhyale hawaiensis
No full textSex-specific physiological differences can modulate the toxicity of contaminants; however, the relationship between these differences and the physicochemistry of toxicants remains understudied. Our objective was to investigate sex-specific differences in the acute toxicity of nine priority polycyclic aromatic hydrocarbons (PAHs) with varying physicochemical properties (logKow: 3.30–6.63) in the tropical marine amphipod Parhyale hawaiensis. Adult males and females were exposed (96 h), toxicity thresholds (LCx and ECx) were determined, and Toxic Units (TUs), Hazard Quotients (HQs), and Risk Quotients (RQs) were computed to assess environmental risks. The results revealed a consistent pattern of heightened sensitivity in females for all the tested PAHs. For the most toxic mid-range compounds (logKow 4.4–4.95), females were significantly (p ≤ 0.05) more sensitive than males, with LC50 values of 111.3 µg/L in females and 190.3 µg/L in males for phenanthrene. This heightened sensitivity was particularly evident at lower effect thresholds, where female EC10 values for the most toxic PAHs were approximately two-fold lower than those for males. Toxicity was nonlinear with respect to hydrophobicity, and mid-range PAHs (logKow 4.4–4.95) posed the highest acute toxicity risk. Consequently, the calculated Risk Quotient for phenanthrene in females (RQ = 14.44) was nearly 30 times the Level of Concern (0.5). This study provides foundational toxicity data for a key tropical species, demonstrating that risk assessments that overlook both sex-specific vulnerabilities and the distinct threats of mid-range PAHs may fail to protect critically important tropical marine ecosystems
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