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A large-scale framework for deriving tidal flat topography from SWOT data
No full textTidal flat topography is a fundamental attribute affecting inundation dynamics, sediment transport, and ecosystem functioning, yet accurate and spatially consistent large-scale monitoring remains challenging. Here, we leveraged satellite altimetry from the Surface Water and Ocean Topography (SWOT) mission to develop a novel, large-scale framework for deriving tidal flat topography from SWOT data, and demonstrated its capability by generating a high-accuracy, national-scale elevation dataset for China. By combining a percentile-based aggregation of multi-temporal water-surface elevation observations with a tide-constrained, adaptive best-quantile (best-q) reconstruction strategy, followed by linear interpolation for gap filling, we improved both vertical accuracy and spatial completeness. Validation against airborne LiDAR, GNSS-RTK surveys, and ICESat-2 photon data demonstrates robust performance across diverse coastal settings, achieving RMSE = 0.34–0.47 m and R2 = 0.81–0.88 at a horizontal resolution of 100 m. Compared with existing large-scale digital elevation models (DEMs), the SWOT-derived topography not only improves vertical accuracy by over 80% but also providing substantially more complete spatial coverage of tidal flat elevations. Spatial analyses reveal pronounced latitudinal gradients, with higher tidal flats concentrated in low-latitude regions and extensive low-lying flats dominating northern estuarine and deltaic systems. This study establishes a scalable framework for tidal-flat elevation retrieval and provides a foundational dataset to support coastal monitoring and sustainable management
Privacy Enhancing Technologies for Intelligent Healthcare: Research Challenges and Opportunities
No full textThe efficient and secure processing of confidential health data always remained an important challenge for healthcare professionals and policymakers as this information needs to be shared among several parties for both data analytics and improved health treatments. In this regard, Privacy Enhancing Technologies (PETs) have already shown great potential in deploying intelligent healthcare systems for improved prognosis and diagnosis. This article explains important privacy-preserving techniques by focusing on their security models and performance issues. It specifically discusses libraries and tools that can be used to implement a particular PET model. Moreover, a detailed comparison is provided to highlight the strengths and weaknesses of each of the privacy enhancing approaches. It further sheds light on the security requirements of the health sector and summarizes state-of-the-art homomorphic encryption, secure multi-party computation, differential privacy, and trusted execution environment approaches used in the healthcare setting. Finally, important parameters are discussed that must be kept in consideration while choosing an optimal PET. The survey is concluded by presenting some future directions to improve the performance of PETs and their usage in the healthcare domain. To the best of our knowledge, it is the first article that comprehensively discusses PETs in the context of healthcare
From fabric to process: An integrated study of deformed quartz-rich carbonates
No full textThis study investigates the presence and nature of diffuse deformation in a low-porosity carbonate rock that underwent polyphase tectonics and contains a network of veins, tectonic stylolites, and deformation bands. By using a non-destructive methodology based on Electron Backscatter Diffraction, X-ray computed tomography, coupled with results from Anisotropy of Magnetic Susceptibility and the Fry technique, we examine the grain fabric and strain distribution within the rock. Our investigation reveals evidence of quartz reorientation with respect to the polyphase contractional history of the area. Several mechanisms of quartz reorientation were proposed, including rigid reorientation during rotation and diffusion-related processes. The coexistence of ductile and brittle deformation mechanisms in the carbonate matrix indicates a complex response to compaction which can be recorded by the matrix, but does not appear to have a direct effect on the actual amount of shortening, as this is predominantly affected by the deformation bands. Our findings highlight the complexity of strain accommodation, with diffuse deformation creating subtle variations in grain size, shape, and orientation within the carbonate matrix. The study enhances our understanding of deformation processes in poly-deformed carbonate rocks and provides valuable insights into the geological context of the studied locations, by using a novel technique that can be useful for gaining qualitative and quantitative information from the rock samples. However, linking specific reorientation mechanisms to individual tectonic events remains challenging due to the multifaceted nature of deformation processes operating over different magnitudes and timescales
Quantum information processing with spatially structured light
No full textQudits have proven to be a powerful resource for quantum information processing, offering enhanced channel capacities, improved robustness to noise, and highly efficient implementations of quantum algorithms. The encoding of photonic qudits in transverse-spatial degrees of freedom has emerged as a versatile tool for quantum information processing, allowing access to a vast information capacity within a single photon. We examine recent advances in quantum optical circuits with spatially structured light, focusing particularly on top-down approaches that employ complex mode-mixing transformations in free space and fibers. We highlight circuits based on platforms such as multi-plane light conversion, complex scattering media, multi-mode, and multi-core fibers. We discuss their applications for the manipulation and measurement of multi-dimensional and multi-mode quantum states. Furthermore, we discuss how these circuits have been employed to perform multi-party operations and multi-outcome measurements, thereby opening new avenues for scalable photonic quantum information processing
Fish Diversity and Invasive Species Detection in the Perak River, Malaysia, Through eDNA Metabarcoding
No full textFreshwater ecosystems are among the most threatened globally, facing rapid biodiversity declines due to habitat degradation, pollution, overexploitation, and invasive species introductions. Southeast Asia, recognized as a global freshwater biodiversity hotspot, is experiencing some of the highest extinction risks. The Perak River, Malaysia’s second-longest river, supports diverse fish communities critical for regional ecological stability and food security, but comprehensive biodiversity assessments have been lacking. This study used environmental DNA (eDNA) metabarcoding targeting the 12S rRNA gene to comprehensively assess fish diversity and detect invasive species across the Perak River. Water samples from five locations were analyzed using high-throughput sequencing on the Illumina MiSeq platform. We identified 16 orders, 32 families, 51 genera, and 57 species, with Cyprinidae being the dominant family (15.78% of species). Invasive species such as Micropterus salmoides, Oreochromis spp., and Gambusia affinis recognised as invasive either globally or in Malaysia were also detected, raising ecological concerns. Our results highlight the efficiency of eDNA metabarcoding for non-invasive biodiversity monitoring in tropical river systems and demonstrate its potential for early detection of invasive species. This pioneering baseline study provides essential data to guide conservation strategies, inform management policies, and contribute to broader efforts addressing freshwater biodiversity loss in Southeast Asia
A mixed methods systematic review of the psychosocial and rehabilitative impact of prison technology with recommendations for practice
No full textExtant research suggests the use of technology in prisons can improve their safety, legitimacy, environment, and efficiency. Recently, mechanisms have also been described throughwhich technology may contribute to rehabilitation. However, less is known about the psychologicalprocesses that explain this outcome. Here we present a systematic review addressing this lacuna.The Preferred Reporting Items for Systematic reviews and Meta-Analyses (PRISMA) method wasapplied to search six databases (Scopus, PsycINFO, LISTA, Criminal Justice Abstracts, Web of Scienceand Academic Search) and grey literature in October 2020. Studies were included if participantswere people living in prison, the intervention was a technological innovation to support arehabilitative environment, and outcomes were psychological or behavioural. Fourteen reports ofthirteen studies met the criteria, and quality assessment checks were performed. Analysis usingmeta-aggregation identified five integrated findings. A broad range of technologies have beenintroduced to prisons. Technologies were found to positively influence the emotions, thinking,behaviour, and relationships of those living in prisons. However, technology failures weredetrimental experiences for prisoners. The findings are used to shape recommendations for howtechnology might contribute to the psychosocial and rehabilitative environment of prisons. <br/
Parametric set-theoretic Yang-Baxter equation: p-racks, solutions & quantum algebras
No full textThe theory of the parametric set-theoretic Yang-Baxter equation is established from a purely algebraic point of view. The first step towards this objective is the introduction of certain generalizations of the familiar shelves and racks called parametric (p)-shelves and racks. These objects satisfy a parametric self-distributivity condition and lead to solutions of the Yang-Baxter equation. Novel, non-reversible solutions are obtained from p-shelf/rack solutions by a suitable parametric twist, whereas all reversible set-theoretic solutions are reduced to the identity map via a parametric twist. The universal algebras associated to both p-rack and generic parametric, set-theoretic solutions are next presented and the corresponding universal ℛ-matrices are derived. The admissible universal Drinfel’d twist is constructed allowing the derivation of the general settheoretic universal ℛ-matrix. By introducing the concept of a parametric coproduct we prove the existence of a parametric co-associativity. We show that the parametric coproduct is an algebra homomorphism and the universal ℛ-matrices satisfy intertwining relations with the algebra coproducts
Africanus III. pfb-imaging–A flexible radio interferometric imaging suite
No full textThe popularity of the CLEAN algorithm in radio interferometric imaging stems from its maturity, speed, and robustness. While many alternatives have been proposed in the literature, none have achieved mainstream adoption by astronomers working with data from interferometric arrays operating in the big data regime. This lack of adoption is largely due to increased computational complexity, absence of mature implementations, and the need for astronomers to tune obscure algorithmic parameters. This work introduces pfb-imaging: a flexible library that implements the scaffolding required to develop and accelerate general radio interferometric imaging algorithms. We demonstrate how the framework can be used to implement a sparsity-based image reconstruction technique known as (unconstrained) SARA in a way that scales with image size rather than data volume and features interpretable algorithmic parameters. The implementation is validated on terabyte-sized data from the MeerKAT telescope, using both a single compute node and Amazon Web Services computing instances
Simulating an Autonomous System in CARLA using ROS 2
No full textAutonomous racing offers a rigorous setting to stress test perception, planning, and control under high speed and uncertainty. This paper proposes an approach to design and evaluate a software stack for an autonomous race car in CARLA: Car Learning to Act simulator, targeting competitive driving performance in the Formula Student UK Driverless (FS-AI) 2025 competition. By utilizing a 360° light detection and ranging (Li-DAR), stereo camera, global navigation satellite system (GNSS), and inertial measurement unit (IMU) sensor via ROS 2 (Robot Operating System), the system reliably detects the cones marking the track boundaries at distances of up to 35 m. Optimized trajectories are computed considering vehicle dynamics and simulated environmental factors such as visibility and lighting to navigate the track efficiently. The complete autonomous stack is implemented in ROS 2 and validated extensively in CARLA on a dedicated vehicle (ADS-DV) before being ported to the actual hardware, which includes the Jetson AGX Orin 64GB, ZED2i Stereo Camera, Robosense Helios 16P LiDAR, and CHCNAV Inertial Navigation System (INS)
Shaping illiberal citizenries:Far-right justifications of educational structures
No full textEducational structures do not only have pedagogical implications; by defining and ranking categories of teaching and learning, and by assigning individuals to these categories, they also contribute to shaping the identity and stratification of citizenries. It is this latter dimension that is often mobilised in the political debate on structures. Existing literature in sociology and politics shows that the main parties in post-World War II Europe have typically invoked liberal citizenship norms based on solidarity, autonomy and pluralism in this debate to appeal to both domestic electorates and international audiences. But what about those who disagree with liberal and egalitarian understandings of citizenship? This paper examines one such movement: the post-1945 Western European far right. Applying rigorous content analysis to an extensive original database of archival documents, we show that extreme and radical right parties and intellectual organisations largely advocate highly stratified education systems and justify this preference with social-order based citizenship norms – but we also find rhetorical variation. While existing theories of liberal-democratic education politics can serve to understand some of this variation, more specific theorising may be needed for educational research to develop a finer-grained understanding of the rhetorical and positional choices of actors who reject liberal-democratic principles.</p
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