SACM - United Kingdom
Permanent URI for this collectionhttps://drepo.sdl.edu.sa/handle/20.500.14154/9667
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Item Restricted ‘The Legality of NATO Military Interventions: Balancing Collective Defense and International Law’(The University Of Edinburgh, 2024) Alanazi, Khalid; Neff, StephenNATO Military Interventions Legal Frameworks Collective Defense International Law North Atlantic Treaty Article 5 Non-Article 5 Operations Peace Enforcement Stabilization Missions 1999 Kosovo Intervention Humanitarian Intervention Responsibility to Protect (R2P) United Nations Charter Legality and Legitimacy Humanitarian Impact Global Peace and Security International Legal Standards Precedents in NATO Actions Humanitarian Outcomes and Consequences26 0Item Restricted Active Power Filters for Industrial Loads(University of Strathclyde, 2024-08) Alanazi, Khalid; Campos-Gaona, DavidHigh-power industrial loads, such as induction ovens and machine drives, frequently use uncontrolled rectifiers that introduce significant harmonic content into AC networks. This harmonic current can distort the voltage at the point of common coupling (PCC), negatively impacting other connected loads by reducing efficiency, increasing equipment wear, and potentially causing transformer saturation. Excessive heating and noisy operation in motors are further consequences. To mitigate these effects and improve overall system efficiency, distribution system operators (DSOs) may penalize customers generating high harmonic levels, incentivizing harmonic reduction measures. Active power filters (APFs) are designed to address these harmonics. They measure the load current, extract the harmonic and reactive components, and supply these back into the system to counteract the unwanted currents. APFs are categorized into series, shunt, and hybrid types. Series APFs inject voltage in series with the grid to maintain nominal load voltage during voltage sags or swells, while shunt APFs are parallel-connected to supply local reactive and harmonic components. Hybrid APFs combine active and passive elements for enhanced performance. APFs offer several advantages, including improved power quality, reduced thermal stress on electrical components, minimized electronic interference, and enhanced system efficiency. They adapt to changing harmonic currents in real-time, unlike passive filters that are tuned for specific harmonics and cannot adjust to varying loads. Passive filters, such as single-tuned, double-tuned, and high-pass filters, may require multiple units for comprehensive harmonic elimination, increasing cost and space requirements.25 0Item Restricted An investigation into 1-methyl-3-octyl imidazolium toxicity in the undifferentiated HepaRG cell line(Saudi Digital Library, 2023) Alanazi, Khalid; Wright, MattThe 1-Methyl-3-Octyl Imidazolium (M8OI) was recently detected in the environment using rat progenitor (B-13) cell lines in a toxicity screen. M8OI has subsequently been proposed as a potential trigger for Primary Biliary Cholangitis (PBC), an autoimmune liver disease. The HepaRG cells were used to investigate the M8OI toxicity because they are human progenitor like cells that can differentiate into both hepatocytes as well as cholangiocytes. In previous studies, undifferentiated HepaRG cells were shown to be relatively insensitive to M8OI toxic effects compared to B13 cells. This study aims to examine the insensitivity of undifferentiated HepaRG cells to M8OI. Increased medium glucose concentrations did not afford protection to undifferentiated HepaRG cells, in contrast to B-13 cells. Seahorse assay indicated that undifferentiated HepaRG cells consumed significantly less oxygen compared to B-13 cells when normalised for protein. Further, M8OI was less potent as an inhibitor of oxygen consumption in HepaRG cells compared to B-13 cells. This study also investigated whether undifferentiated HepaRG cells expressed CYP1A1, which could be capable of converting M8OI into non-toxic compounds. The results of this study indicated that undifferentiated HepaRG cells had negligible CYP1A1 activity although low levels were detectable after treatment with beta-naphthoflavone. These data suggest that undifferentiated HepaRG cells are less sensitive to M8OI toxicity compared to B-13 cells due to reduced reliance on mitochondrial oxidative phosphorylation combined with reduced sensitivity to M8OI inhibitory action on the electron transport chain. Expression of functional CYP1A1 activity was not responsible for reduced sensitivity to M8OI.24 0