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Continuous-Variable Quantum Key Distribution with Composable Security and Tight Error Correction Bound for Constrained Devices
Get PDFConstrained devices, such as smart sensors, wearable devices, and Internet of Things nodes, are increasingly prevalent in society and rely on secure communications to function properly. These devices often operate autonomously, exchanging sensitive data or commands over short distances, such as within a room, house, or warehouse. In this context, continuous-variable quantum key distribution (CV-QKD) offers the highest secure key rate and the greatest versatility for integration into existing infrastructure. A key challenge in this setting, where devices have limited storage and processing capacity, is obtaining a realistic and tight estimate of the CV-QKD secure key rate within a composable security framework, with error correction (EC) consuming most of the storage and computational power. To address this, we focus on low-density parity-check (LDPC) codes with non-binary alphabets, which optimise mutual information and are particularly suited for short-distance communications. We develop a security framework to derive finite-size secret keys near the optimal EC leakage limit and model the related memory requirements for the encoding process in one-way error correction. This analysis facilitates the practical deployment of CV-QKD, particularly in constrained devices with limited storage and computational resources
Multi-agent Q-learning with particle filtering for UAV tracking in Open-RAN environment
Get PDFThis paper introduces a method for target tracking that leverages mobile sensor nodes and Unmanned Aerial Vehicles (UAVs) within an Open- Radio Access Network (RAN) framework. Open-RAN is a flexible and standardized architecture that allows open and interoperable components in RANs, promoting efficiency and adaptability. The core methodology involves improving the accuracy and energy consumption tracking in urban areas filled with obstacles and dynamic conditions. Mobile sensor nodes use a particle filtering algorithm to detect and estimate target positions, and this information is relayed to nearby Evolved/Next Generation Node Bs (e/gNBs), which function as the radio access network infrastructure. The e/gNBs manage clusters of UAVs using a specialized xApp integrated into the near-real-time RAN Intelligent Controller (RIC). The UAVs utilize a comprehensive tracking strategy based on received signal strength (RSS), a trilateration algorithm, and an enhanced multi agent Q-learning algorithm (eMAQL). This approach enables UAVs to optimize their flight paths while balancing accuracy, power usage, and communication delays
Foot peripheral sensory neuropathy: a frequent disabling manifestation in systemic sclerosis
Get PDFObjectives: Peripheral sensory neuropathy (PSN) is an under-recognized feature in SSc. Moreover, SSc foot involvement is frequent but poorly
investigated. We aimed to provide a detailed characterization of foot PSN in a large cohort of SSc patients, describing its associations with
disease-specific features, physical disability and quality of life (QoL).
Methods: SSc patients and healthy controls (HCs) comparable for age and gender were enrolled in a cross-sectional observational case-control
study. All subjects underwent a detailed quantitative sensory testing of feet evaluating touch, vibratory, thermal and pain sensitivity, ultimately
investigating the presence of large and small fiber neuropathy. Patient-reported outcomes (Scleroderma Health Assessment Questionnaire,
Manchester Foot Pain and Disability Index and Systemic Sclerosis Quality of Life Questionnaire) were administered to assess neuropathic
symptoms, foot disability and QoL.
Results: A total of 109 SSc patients (88.1% female, median age 59.0 years) and 51 HC were enrolled. SSc patients presented with a significant
impairment in each sensory parameter assessed (P ≤ 0.01 for all). Foot PSN was present in 85.3% of the patients, with 80% having small fiber
and 57% large fiber neuropathy, co-existing in 51.4% of the cases. PSN was associated with age, smoking, foot ulceration, disease duration
and corticosteroids use. Precisely, 80.6% subjects with PSN reported at least one neuropathic symptom. Patients with neuropathic symptoms
reported worse physical function, worse foot disability and more impaired QoL.
Conclusion: Foot PSN presents as a common and disabling manifestation in SSc patients, involving small and large fibres. Hence, foot PSN
assessment should be included as a part of the SSc workup
RNA-seq analysis reveals transcriptome changes in livers from Efcab4b knockout mice
Get PDFEFCAB4B is an evolutionarily conserved protein that encodes for the Rab GTPase Rab46, and the CRAC channel modulator, CRACR2A. Previous genome wide association studies have demonstrated the association of EFCAB4B variants in the progression of non-alcoholic fatty liver disease (NAFLD). In this study we show that mice with global depletion of Efcab4b−/− have significantly larger livers than their wild-type (WT) counterparts. We performed RNA-sequencing (RNA-seq) analysis of liver tissues to investigate differential global gene expression among Efcab4b−/− and WT mice. Of the 69 differentially expressed genes (DEGs), analyses of biological processes found significant enrichment in liver and bile development, with 6 genes (Pck1, Aacs, Onecut1, E2f8, Xbp1, and Hes1) involved in both processes. Specific consideration of possible roles of DEGs or their products in NAFLD progression to (NASH) and hepatocarcinoma (HCC), demonstrated DEGs in the livers of Efcab4b−/− mice had roles in molecular pathways including lipid metabolism, inflammation, ER stress and fibrosis. The results in this study provide additional insights into molecular mechanisms responsible for increasing susceptibility of liver injuries associated with EFCAB4B
Low-micromolar Quantification of Fluorinated Analytes Using Hyperpolarised 19F Benchtop NMR
Get PDFBenchtop NMR spectrometers are more affordable and accessible than high-field NMR instruments but suffer from higher limits of detection (LOD) and lower chemical shift resolution due to their moderate magnetic fields. Here we demonstrate reductions in the single-scan LOD values for 19F benchtop (1 T) NMR of 3,5-difluoropyridine (DFP) and 2,4,6-trifluorobenzylamine (TFBA) to (6.84 ± 0.45) μM and (162 ± 28) μM via SABRE (Signal Amplification By Reversible Exchange) hyperpolarisation. Further reductions in LOD to (600 ± 20) nM and (17.5 ± 2.0) μM are achieved by combining SABRE with SHARPER (Sensitive, Homogeneous, And Resolved PEaks in Real time) detection. Quantification is demonstrated over the micromolar concentration range using linear external calibration. The effects of polarisation transfer to the solvent via proton exchange in the case of TFBA are shown to be minimised in methanol-d4; however, 19F detection and quantification are also achieved in protio methanol, with a LOD of (42.6 ± 3.6) μM
Combined clinoptilolite and Fe(O)OH for efficient removal of Cu(II) and Pb(II) with enhanced solid–liquid separation
Get PDFThis study investigated combining fine clinoptilolite with iron hydroxide coagulant, as a cost-effective, dual-purpose flocculant for enhanced removal of Pb2⁺ or Cu2⁺ ions, along with the solid–liquid separation and physicochemical analysis. For the clinoptilolite, adsorption kinetics fitted a pseudo-second-order (PSO) rate model with higher rate constants for Pb2+, while equilibrium adsorption data fitted the Langmuir monolayer model, with Qmax similar at 18.8 mg/g for Pb2+ and 18.3 mg/g Cu2+. TEM elemental mapping of the clinoptilolite evidenced areas of K and Fe impurities, while SEM suggested a uniform distribution of aggregates comprising a clinoptilolite core with decorated FeOOH. X-ray diffraction (XRD) indicated the FeOOH phase as α-FeOOH (Goethite) with no change in structure on inclusion of adsorbed Pb2+. Combined clinoptilolite-FeOOH flocs were significantly larger than FeOOH only precipitates, while flocs formed from 0.5 wt% FeOOH and 1 wt% clinoptilolite produced the fastest settling rates and greatest consolidation. Compressive yield stress data also correlated with enhanced dewatering of the combined systems, due to the dense clinoptilolite acting as a weighter material. For final metals removal, combined flocs outperformed FeOOH across a broad concentration range, achieving > 98% removal for both Pb2⁺ or Cu2⁺. The greater metals removal combined with denser floc production and improved settling features highlights significantly enhanced performance above that possible from either ion exchange or precipitation alone
Tropical cyclone induced compound flooding in Madagascar: a coupled modeling approach
Get PDFCompound flooding occurs when multiple contributing factors, such as oceanic (storm surge, tide, and waves) and continental (heavy rainfall and river discharge), combine to exacerbate flood impacts. Tropical cyclone (TC)-induced compound flooding is a major hazard and societal concern, particularly in underdeveloped, highly exposed and vulnerable countries like Madagascar. Despite being repeatedly impacted by TCs, the region receives little attention from the scientific community, particularly in the modeling of TC-induced flooding and associated hazards. Here, we developed a high-resolution (30 m) compound flood model over Madagascar. The model is nested in a regional tide-surge-wave model purpose-built for this region. A dedicated topographic and bathymetric dataset was developed to accurately represent the whole land–ocean continuum. Using this framework, we modeled a recent intense TC Batsirai (2022) and assessed the resulting flooding. Our model shows good accuracy, achieving a hit ratio of 0.83 when matched with the remote sensing derived flood map. Our results demonstrate that the TC-induced flooding in this region is compound in nature, with flooding being significantly underestimated when continental factors (e.g. rainfall-runoff) are excluded. The impact of the ocean is primarily observed along the coastline, extending 5–10 km inland along the rivers. Additionally, we identified a non-linear interaction between oceanic and continental factors, which has important implications for the numerical modeling of such compound flood events. We estimate that at least 30% of the flooded area in our modeled domain comprises agricultural lands, highlighting the potential for significant societal impact. The developments and findings of this study pave the path forward for a national-scale compound flood modeling over Madagascar at a resolution suited for household-scale flood risk and impact assessments
The role of long‐term hydrodynamic evolution in the accumulation and preservation of organic carbon‐rich shelf sea deposits
Get PDFUnderstanding and mapping seabed sediment distribution in shelf seas is essential for effective coastal management, offshore developments, and for blue carbon stock assessments and conservation. Fine-grained marine sediments, particularly muds, play a key role in long-term organic carbon sequestration, so knowledge of the spatial extent of these carbon-rich deposits is important. Here, we consider how changes in shelf sea tidal dynamics since the Last Glacial Maximum have influenced the development of three mud depocenters in the northwest European shelf seas: the Fladen Ground, the Celtic Deep, and the Western Irish Sea Mud Belt. Using a new high-resolution paleotidal model, we demonstrate how the evolution of simulated tidal parameters, including bed shear stress and bottom boundary layer thickness, differ across these sites. Geological data support our findings, indicating that long-term mud sedimentation continues to the present in the Celtic Deep and Western Irish Sea Mud Belt, while in the Fladen Ground, accumulation cannot be fully explained by contemporary hydrodynamics. In the latter, mud deposition is relict, deposited during quiescent tidal conditions between 17,000 and 5,000 years ago. We suggest that simulating paleoceanographic conditions can contribute to understanding first-order sediment dynamics over large spatial and temporal scales, a key input for predictive mapping and regional blue carbon inventories. This approach is a valuable first step in data-poor regions to identify potential fine sediment deposits. By illustrating the temporal evolution of organic carbon-rich deposits, we provide a broader context for managing organic carbon storage in shelf sea sedimentary environments
Affect, collective action and the policy process in housing safety crises
Get PDFInternational failures in housing safety have created complex policy problems for national governments, as well as creating severe negative impacts for those living in homes with significant defects. This article focuses on two cases—the post-Grenfell building safety crisis in England, and the defective concrete blocks or ‘mica’ crisis in Ireland—to explore the relational dynamics of policy processes, focusing on the role of affects. Through in-depth interviews with 28 residents living through these crises, the research explores how policy shapes collective affects and how, in turn, feelings associated with the crises can be reconfigured through collective action to influence the policy process. The concept of counter-affects is mobilised to explain how the ‘subjects’ of policy interventions strategically deploy personal stories to shape new collective feelings about the crises, disrupting the operation of power through the policy process. By building counter-affects of solidarity, recognition, empathy, and outrage, collective movements associated with housing safety crises built a broader coalition oriented towards the achievement of policy goals. Whilst effective, this strategy also has repercussions in the re-enactment of feelings of crisis, uncertainty, and unsafety
Wall of visas: how race impacts the externalization of (forced) migration control in south-south migration corridors
Get PDFExternalization happens when countries “extend” their borders beyond their territorial limits. While existing literature on it focuses on the “Global North”, similar practices in the “Global South” are understudied and implemented differently, with a greater use of visas as a hidden type of externalization strategy. Little is known on whether these practices are racially determined. We partly fill this gap; focusing on Brazil, we demonstrate how it uses humanitarian visas for Haitians and family reunification visas for Sub-Saharan African refugees as an externalization strategy to control the (forced) migration of black forced migrants to Brazil. We draw from thematic analysis of legislation, minutes from official meetings, interviews with stakeholders and diplomatic archival research. We show that, despite its “liberal” migration policy, Brazil's visa policies instead function as a hidden externalization strategy, operating as a metaphorical “racial wall of visas”, keeping mainly black (forced) migrants out, preventing them from receiving protection
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