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A Review of Modelling, State of Charge Estimation and Management Methods of EV Lithium-Ion Batteries
No full textElectric Vehicles (EVs) can contribute significantly to reducing greenhouse gas emissions and addressing climate change problems. Modern EVs are primarily powered by electrochemical batteries such as lead-acid (Pb-acid), nickel-metal hydride (NiMH), sodium-ion (Na-ion), solid-state and lithium-ion (Li-ion) batteries. When compared to other battery types, Li-ion batteries are the most suitable for EV applications due to their practical features such as their high energy density, high charging and discharging efficiency and extended lifetime. However, the main risk of Li-ion batteries is that they are exposed to thermal runaway phenomena, which raises severe concerns about the safety of EV propulsion systems. Thermal runaways should be considered carefully as they cannot be stopped once they start and can lead to battery explosion. One of the main reasons leading to this phenomenon is abusing the state of charge (SoC) of the battery. Therefore, the battery management system (BMS) plays a crucial role in mitigating the stimulation of the thermal runaway process by accurately estimating and properly managing the battery cells. To help researchers and designers with understanding this matter, this paper proposes a review of the most effective SoC estimation methods for EV Li-ion batteries and links these methods with practical energy management systems in the EV market
Correction : Randomization in the age of platform trials: unexplored challenges and some potential solutions
No full textHost state’s policy and institutional challenges in addressing transnational repression within their borders: the case of the Egyptian diaspora in the UK
No full textThe Egyptian government's crackdown on dissent extends beyond its borders, with diaspora members facing threats and intimidation even in exile. This article examines the institutional and policy challenges host states face when attempting to tackle transnational repression within their borders, focusing on the post-2013 Egyptian diaspora in the UK as a case study. It highlights that the UK still lacks the necessary awareness and policy tools to adequately respond to the authoritarian targeting of individuals on its territory. The article provides the first systematic review of the background, mechanisms, and consequences of transnational repression against Egyptians in the UK, laying the groundwork for a more critical discussion and contributing to calls for policy reforms to safeguard diaspora rights in host states
Widespread biophysical cooling effects due to post-fire greening
No full textWildfires and greening are two important biophysical processes that influence land surface-climate feedback patterns. However, the impact of post-fire greening, which primarily reflects canopy structural recovery, on land surface temperature (LST) remains uncertain, particularly at the daily scale, as this temporal resolution allows for a clearer observation of how fire seasonality and vegetation regrowth influence short-term land surface energy dynamics. In this research, using satellite sensor observations covering the globe from 2004 to 2019, we found that the median post-fire recovery time of leaf area index (LAI) was 479.5 days. Most forests exhibited faster canopy LAI recovery than low-stature herbaceous vegetation, likely due to differences in burn severity and affected plant structures. Fire seasonality also shaped LAI recovery patterns: dry-season and spring fires led to quicker regrowth, with the shortest recovery in temperate spring fires (173.7 days), while wet-season and summer fires showed delayed recovery, especially in cold zones where summer fires need 425.5 days to recovery. During post-fire greening, the annual cycle of LAI recovery caused an average cooling effect of −0.04 K d-1, due to the strong evapotranspiration-climate negative feedback. However, seasonal effects varied: summer fires in temperate and cold zones led to cooling, with the strongest warming observed after temperate winter fires (up to 0.104 K d⁻1). Furthermore, we observed a widespread decrease in carbon use efficiency during post-fire LAI recovery, which means that the recovery rate of ecosystem carbon sinks may not be synchronized with the rate of vegetation greening. By distinguishing between structural and functional recovery, we found that early evapotranspiration-driven cooling during structural recovery may not persist throughout ecosystem functional recovery. This study enhances our understanding of the global biophysical climate effects of post-fire greening in the context of the earth’s land surface-climate feedback, and reveals precise changes in the component parts of this feedback effect
Purified Zymogens Reveal Mechanisms of Snake Venom Metalloproteinase Auto-Activation
No full textSnake venoms contain diverse mixtures of toxins that evolved to incapacitate prey, but in humans they cause extensive pathology following snakebite envenomation. In viper venom, the most potent toxins are the haemorrhagic and coagulopathic snake venom metalloproteinases (SVMPs). Because venoms contain a SVMP cocktail, and due to their cytotoxicity, SVMP characterizations have been hampered by the lack of purified enzymes. By incorporating their prodomain, which blocks the active SVMP site, we overcame their cytotoxicity and enabled recombinant production of zymogens from all three structurally variable SVMP classes (PI, PII and PIII) using our baculovirus/insect cell expression system. Zymogens were auto-activated by incubation with Zn2+ ions, resulting in prodomain cleavage, PII disintegrin cleavage and PIII prodomain proteolysis. Auto-activated SVMPs were characterized using protein substrate degradation, platelet aggregation and blood coagulation assays, benchmarked to native venom-purified SVMP. Our recombinant zymogen production protocol is generically applicable for the expression of SVMPs, unlocking biomedical use in haematology, and discovery of novel snakebite therapeutics
Generalized Additive Model With Dynamic Coefficients for Spatiotemporal Ozone Predictions
No full textAccurate prediction of surface‐level ozone concentrations is critical for air quality management and public health protection. This study develops a flexible spatiotemporal statistical modeling framework to predict daily mean O3 concentrations across Italy by integrating satellite‐derived ozone estimates with ground‐based observations and high‐resolution environmental predictors. The proposed model is based on a linear regression with dynamic intercept and slope that relate in situ O3 measurements to satellite data, explicitly addressing additive (systematic shifts) and multiplicative (scaling) biases in satellite‐derived ozone estimates. These spatiotemporally varying coefficients are modeled through a generalized additive model framework, allowing the capture of complex and potentially nonlinear relationships between ozone levels and environmental covariates. This unified and interpretable approach enables a detailed understanding of bias patterns in satellite data. Model diagnostics and crossvalidation demonstrate superior explanatory power and predictive performance compared to simpler models. The interpretability of the model is illustrated by revealing the influence of elevation, nitrogen dioxide concentrations, and seasonal variation on bias structures. Furthermore, the model's downscaling capability is demonstrated by producing fine‐scale ozone concentration predictions over Italy and its surrounding regions. The proposed modeling framework offers an accurate, scalable, and interpretable tool for mapping surface‐level ozone, supporting improved environmental monitoring and informing policy decisions
Experimental Observation of Self-Organised Mode-Locked Emission in a W-Band Free-Electron Maser
Get PDFExperimental observation is reported of passive, self-organised mode-locking in a high-power free-electron maser (FEM) oscillator operating near 103 GHz, using a ∼1.36 MeV, 1.15 A energy-recovered electron beam. Macropulses of 10 μs duration were recorded in which mode-locking is established from the onset of measurable radiation and persists throughout the pulse. Power-detector and heterodyne measurements show a regular train of kW-level spikes with a spacing of 10.4 ns, consistent with the cavity free spectral range. A modal analysis of the intermediate-frequency signal reveals strong phase coherence across more than sixteen longitudinal modes. A distinct sideband appears with a spacing that remains stable to within 0.2 MHz even though the carrier frequency drifts by several megahertz between pulses due to variations in beam energy. This behaviour contradicts the power-dependent scaling expected from synchrotron-driven FEL sidebands and instead indicates a cavity-anchored coupling mechanism. The results demonstrate that robust passive mode-locking can arise naturally in mm-wave FEM oscillators without external modulation