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Combinatorial solutions to the Social Golfer Problem and the Social Golfer Problem with adjacent group sizes
No full textThe Social Golfer problem (SGP) consists of scheduling v players into rounds of equally sized groups in such a way that (1) any two players are assigned to the same group in at most one round and (2) as many rounds as possible are obtained. Combinatorial properties dictate the maximum theoretical number of rounds that may or may not be achievable. Any solution with the theoretically maximum number of rounds is called a maximal solution, and solutions with the number of rounds that is the best currently known (but not necessarily maximal) are said to be optimal. Existing techniques to find optimal solutions consist of exhaustive search methods and constructions based on combinatorial structures such as mutually orthogonal Latin squares (MOLSs) and mutually orthogonal Latin rectangles (MOLRs). In this paper, we investigate other combinatorial designs that can provide optimal solutions with at least as many rounds as those published and introduce novel constructions based on transversal designs, incomplete transversal designs, and starter blocks. We also provide optimal solutions to a related problem, where group sizes may differ by one but all rounds have the same number of groups of each size (the Social Golfer problem with adjacent group sizes (SGA)). We show how optimal solutions to this problem can be derived from optimal solutions to an instance of the SGP with either more or fewer players. An algorithm is presented to find an optimal solution in general, and solutions are provided for up to 150 players
Comprehensive review of WPC pyrolysis mechanisms and catalysis with emerging AI opportunities
Get PDFWood–plastic composites (WPCs), as hybrid materials of lignocellulosic fibers and thermoplastics, present significant challenges in end-of-life management due to their multiphase and multicomponent nature. Pyrolysis has emerged as an effective thermochemical strategy for converting waste WPCs into fuels and value-added carbon products. This review systematically summarizes recent advances in WPC pyrolysis mechanisms, catalytic upgrading, and kinetic modelling, with particular emphasis on how machine learning (ML) and artificial intelligence (AI) are beginning to reshape process understanding and optimization. The review discusses the catalytic roles of zeolites, metal oxides, and activated carbons, as well as the influence of fillers, compatibilizers, and ageing effects on product selectivity. Increasing attention is being directed toward hybrid kinetic–AI frameworks that integrate experimental datasets with mechanistic constraints to achieve interpretable, transferable, and data-efficient modelling of complex biomass–plastic interactions. Beyond methodological advances, AI-enabled analytics offer practical benefits including accelerated experimental design, improved uncertainty quantification, and data-driven guidance for scale-up. Finally, future priorities are highlighted, including standardized data infrastructures, multi-scale kinetic–reactor modelling, and integration with techno-economic and life-cycle assessment to support carbon-negative and industry-ready WPC pyrolysis systems
Two invariant subalgebras of rational Cherednik algebras
Get PDFOriginally motivated by connections to integrable systems, two natural subalgebras of the rational Cherednik algebra have been considered in the literature. The first is
the subalgebra of all degree zero elements and the second is the Dunkl angular momentum
subalgebra.
In this article, we study the ring-theoretic and homological properties of these algebras.
Our approach is to realise them as rings of invariants under the action of certain reductive
subgroups of SL2. This allows us to describe their centres. Moreover, we show that they are
Auslander–Gorenstein and Cohen–Macaulay and, at t = 0, give rise to prime PI-algebras
whose PI-degree we compute.
Since the degree zero subalgebra can be realized as the ring of invariants for the maximal
torus T ⊂ SL2 and the action of this torus on the rational Cherednik algebra is Hamiltonian,
we also consider its (quantum) Hamiltonian reduction with respect to T. At t = 1, the
quantum Hamiltonian reduction of the spherical subalgebra is a filtered quantization of the
quotient of the minimal nilpotent orbit closure Omin in gl(n) by the reflection group W. At
t = 0, we get a graded Poisson deformation of the symplectic singularity Omin/W
Learning Neighbourhoods in the Developing South: A Practical Toolkit for Cities and Communities. PASCAL Briefing Paper 32
Get PDFExperimental infection of horses with African horse sickness virus results in overt disseminated intravascular coagulation
No full textBackground:
African horse sickness (AHS), caused by the vector‐borne African horse sickness virus (AHSV), is endemic to sub‐Saharan Africa and infection results in high mortality in naïve equine populations. Clinical signs include submucosal petechiae and prolonged bleeding post venepuncture indicative of hypocoagulation. Pathological activation of haemostasis may result from tissue factor expression as a result of vascular endothelial damage or dysfunction, the proposed pathologic mechanism in AHS, potentially resulting in disseminated intravascular coagulation (DIC).
Objectives:
To describe haemostatic changes during experimental AHSV infection and to characterise DIC using plasma‐based and viscoelastic assays.
Study Design:
In vivo experiments.
Methods:
Four horses were experimentally infected with AHSV. Blood samples were obtained before infection, then every 24 h until humane euthanasia. Haematology and thromboelastography (TEG) were performed and prothrombin time (PT), activated partial thromboplastin time (aPTT), fibrinogen and D‐dimer concentrations, as well as activities of antithrombin (AT) and coagulation factors II, VII, VIII, X, and XII were measured.
Results:
Over the disease course, TEG variables showed increased clot initiation time (R) and decreased α‐angle, maximum amplitude (MA), and clot strength (G). The velocity curve showed decreased maximum rate of thrombus generation (MRTG) and thrombus generation (TG), and increased time to maximum rate of thrombus generation (TMRTG). Prothrombin time, aPTT and D‐dimer concentration increased while AT activity decreased. All horses developed severe thrombocytopenia.
Conclusions:
Horses experimentally infected with AHSV developed a consumptive coagulopathy with a bleeding phenotype. These findings fulfil the criteria of overt DIC characterised by procoagulant activation, inhibitor consumption and increased fibrinolytic activity
The scapegoating hypothesis revisited: unpacking blame attribution towards the International Monetary Fund
No full textGovernments in economic hardship that borrow from the International Monetary Fund (IMF) under strict conditionalities are commonly expected to scapegoat the Fund to prevent domestic protest and electoral punishment. But we know little about the micro-level mechanisms underpinnings this scapegoating hypothesis. This paper theoretically specifies and empirically assesses two strategies that governments can employ to shape whom citizens hold responsible for the contested economic policies in IMF programs. After entering IMF programs, governments may deflect responsibility for contested economic policies by either actively shifting blame onto the IMF; or by laying low and hoping on other actors to take the bait. We examine these expectations empirically by employing a survey experiment in Pakistan in June 2023. While this setting constitutes a typical case for the scapegoating hypothesis, both strategies fail to deflect responsibility to the Fund. This surprising nonfinding warrants further research on the scapegoating hypothesis and its scope conditions
Gallium oxide-based photodetectors for water quality monitoring
No full textWe present an approach to water quality monitoring using gallium oxide (Ga2O3) ultrawide-band-gap semiconductors. Nitrates, dissolved organic carbon, and suspended solid concentrations are three commonly measured water quality parameters that display optical absorption ranging from the deep ultraviolet to the visible region. This broad spectral region poses a challenge for accurate and efficient (simultaneous) measurement of absorption/extinction arising from varying concentrations of these parameters because silicon (Si), the classical detector material, has poor performance across this optical region. To overcome these limitations, we propose the use of ultrawide-band-gap semiconductors to trace changes in optical absorption from varying water compositions by measuring the photocurrent response at different wavelengths. Here, we use α-phase Ga2O3 as a suitable material to measure a broad photocurrent response ranging from 200 to 465 nm. The photocurrent response consisted of three well-defined regions inherently linked to the rich electronic landscape of the material. Region (i) (200–250 nm) corresponds to band-to-band excitation of charge carriers, aligning well with the absorption characteristics of nitrates. Region (ii) (250–350 nm) corresponds to band tail-related transitions, allowing a photocurrent response to dissolved organic carbon concentrations. Finally, we utilize defect-mediated transitions in Region (iii) (350–465 nm) to monitor suspended solid concentrations. It was observed here that the sensitivity of the photocurrent response to the changing water composition strongly depends on the excitation wavelength, where 225, 260, and 465 nm excitation yielded (for our setup) the best results for the monitoring of nitrates, dissolved organic carbon, and suspended solid concentrations, respectively
Towards socially robust policy modelling: scoping review of public involvement in computational policy modelling
No full textComputational policy modelling appeals to policymakers seeking to understand potential outcomes of policy decisions, yet there are long-standing concerns about the “social robustness” of the knowledge it generates. A key route to socially robust policy modelling is the active involvement of publics as partners, and not only subjects, of modelling; yet the technical and abstracted nature of the modelling process poses particular challenges for conventional involvement practice. This scoping review of published computational modelling papers which report public involvement explores both practical elements of involvement in modelling and the tacit or explicit justifications authors offer for involving publics. We found a preponderance of professional stakeholders over “lay” publics and a bifurcation between informal feedback and highly structured input. We conclude that approaches to public involvement in computational policy modelling should seek ongoing dialogic involvement across the stages of the modelling process, be more attentive to power dynamics in the involvement process, and consider how involvement can be inclusive of diverse publics
Up-to-date test beam results of ATLAS ITk pixel sensors and modules
Get PDFThe ATLAS Inner Detector will be replaced by a new all-silicon Inner Tracker (ITk) in 2029 to meet the challenges of the High Luminosity LHC (HL-LHC). The ITk pixel system combines 3D sensors at the innermost layer, operating after exposure to fluences of up to 2 × 1016 neq/cm2, with thin n-in-p planar modules in the outer layers. Beam tests are essential for qualifying these sensors and modules before and after irradiation. Recent test beam campaigns in 2024 evaluated new fabrication techniques, thick planar sensors, and modules with the latest ITkPixV2 readout chip, while the 2025 program introduces novel 3D triplet and planar quad configurations. Recent test beam results will be presented here, highlighting sensor performance and readiness of the ITk pixel detectors for HL-LHC operation
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