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Conformal scalar field theory from Ising tricriticality on the fuzzy sphere
Get PDFFree theories are landmarks in the landscape of quantum field theories: their exact solvability serves as a pillar for perturbative constructions of interacting theories. Fuzzy sphere regularization, which combines quantum Hall physics with state-operator correspondence, has recently been proposed as a promising framework for simulating three-dimensional conformal field theories (CFTs), but so far it has not provided access to free theories. We overcome this limitation by designing a bilayer quantum Hall system that hosts an Ising tricritical point—a nontrivial fixed point where first-order and second-order transitions meet—which flows to the conformally coupled scalar theory in the infrared. The critical energy spectrum and operator structure match those at the Gaussian fixed point, providing nonperturbative evidence for the emergence of a free scalar CFT. Our results expand the landscape of CFTs realizable on the fuzzy sphere and demonstrate that even free bosonic theories—previously inaccessible—can emerge from interacting electrons in this framework
Inclusive pedagogies and practices of English for Academic Purposes (EAP) in higher education (HE): An exploratory survey-based study
Get PDFInclusion has become a defining marker of quality and equity in higher education (HE), yet its operationalisation in English for Academic Purposes (EAP) teaching remains underexplored. This paper presents the first empirical phase of a multi-stage BALEAP-funded project investigating inclusive teaching practices in EAP. Using an exploratory qualitative survey of 23 EAP practitioners across diverse institutional roles and global contexts, the study captures how inclusion is understood, enacted, and constrained within English-medium HE environments. Thematic analysis identified two overarching domains: barriers to inclusion, including limited awareness and training, prescriptive curricula, lack of diversity consideration, time constraints, and prohibitive course costs, and approaches to inclusion, encompassing differentiated instruction, culturally responsive pedagogy, reflective practice, personalised learning, and cooperative, student-centred engagement. Findings reveal that while inclusivity is widely endorsed as an ethical and pedagogical imperative, its translation into practice is hindered by structural and institutional limitations. EAP educators often navigate tensions between linguistic rigour and equity, highlighting the need for systemic frameworks that recognise inclusivity as a core professional competency rather than an optional enhancement. The study contributes novel empirical evidence by translating existing inclusion theory into an EAP context and extending the focus from individual practices to an organisational ethos, thereby providing a diagnostic foundation for subsequent project phases that develop practical and policy-oriented recommendations. It argues that meaningful inclusion requires coordinated institutional action aligning policy, curriculum, and professional development to position linguistic and cultural diversity as drivers of educational excellence rather than challenges to be managed
A Validated Mass Spectrometry Platform for Oxysterol Analysis of Single Human Gastruloids and Liver Organoids
Get PDFOxysterols, i.e., hydroxylated cholesterol metabolites, are associated with various signaling pathways and diseases. Their low abundance and structural complexity create analytical challenges, particularly in small sample sizes. We here present an optimized and validated miniaturized sample preparation method that enables oxysterol detection and quantification in single stem cell-derived 3D cell aggregates, as exemplified in human liver organoids (stem cell-based 3D liver models) and human gastruloids (stem cell-based embryo models) using liquid chromatography–mass spectrometry (LC–MS). The method, utilizing enzyme-assisted derivatization with Girard-T reagent, allowed a 10-fold decrease in starting material compared to conventional methodology while maintaining sensitivity and precision. A validation based on Eurachem guidelines confirmed quantitative performance and reproducibility across days and operators. In addition, we introduce a tailored normalization method, allowing same-sample measurements of oxysterols and the total protein content. The miniaturized method enabled successful detection and quantification of oxysterols of expected presence (e.g., 26-hydroxycholesterol), as well as unexpected (24S-hydroxycholesterol) and unknown oxysterols. Using our updated method, we could reveal significant heterogeneity among individual organoids and gastruloids, both between and within cell sources/protocols. Overall, we provide a reliable and high-sensitivity method for analyzing oxysterols in limited biological samples, opening opportunities for further insights into their roles in, e.g., liver function and early embryogenesis
Patterns of Functional Connectivity Differentiate Individuals and Individual Regions in Face and Scene Selective Networks
Get PDFThe perception and recognition of faces and scenes rely on distributed neural systems comprising specialised, category-selective regions in visual cortex that interact with an extended network of cortical regions across the brain. While prior work has demonstrated face- and scene-selective responses can be differentiated based on patterns of whole-brain connectivity, it remains unclear whether category-selective regions within each network also possess distinguishable whole-brain connectivity profiles reflecting their specific functional roles. It is also unclear whether individuals have distinct connectivity profiles that might underlie individual differences in face or scene perception. In this study, we used functional magnetic resonance imaging (fMRI) from multiple different naturalistic movie watching paradigms and at rest. We identified whole-brain functional connectivity fingerprints for each of the core regions within the face and scene processing networks. We found that patterns of functional connectivity were more similar within than between participants and were distinct across individual regions of the face and scene networks. These findings demonstrate that brain regions within category-selective visual networks are characterised by distinctive connectivity profiles with the rest of the brain
Astrocytes: orchestrators of brain gas exchange and oxygen homeostasis
Get PDFIf we consider neurons like muscles during exercise, the demand for oxygen (O2) and carbon dioxide (CO2) elimination is constantly changing. This review summarises the evidence that astrocytes are essential for homeostasis of the respiratory gases in the brain, with a particular focus on oxygen homeostasis. Astrocytes surround cerebral blood vessels and sense changes in oxygen availability in the milieu. They contribute to pH homeostasis and are increasingly recognized for their contribution to central chemosensitivity, particularly in detecting changes in CO2 and proton (H+) concentrations. They are one of the cell types that govern changes in cerebral perfusion rate. Cerebral perfusion dynamically matches tissue metabolism, to balance O2 delivery and CO2 removal. By examining the role of astrocytes as both sensors and effectors in this homeostatic balancing act, this review argues that astrocytes influence the metabolic environment of neural networks with profound implications for cognitive function
Force and aspiration: mobility and class formation on the peripheries of Addis Ababa
Get PDFWhile the emergence of social class is usually associated with relations of production or patterns of consumption, this article argues for centring mobility in class analysis, especially within rapidly growing cities. It focuses on the peripheries of Addis Ababa, where Africa's most remarkable state-led housing programme has produced wrenching sociospatial change. As a wide spectrum of households are sucked or expelled into these peripheries, new constellations have emerged in which varying experiences of residential mobility and everyday physical movement are redrawing lines of difference beyond categories of owner and tenant, rich and poor, formal and informal. We draw on interviews and solicited diaries from residents in various housing types within peripheral neighbourhoods. Deploying the prisms of ‘displaceability’ and ‘motility’ (the potential to be mobile), we argue that agency and confidence regarding one's mobility—the degree to which moving or staying put is a realization of aspiration rather than force—is contributing to class formation, including by sharpening relational differentiation within the urban middle class. As well as shedding light on the reconstitution of class in urban Ethiopia, the article addresses an important gap regarding the role that mobility plays in social class dynamics in contexts of rapid urban growth and transformation
“I think from the beginning, the ambitions were compromised”: a case study of COVAX as vaccine equity policy operationalisation
Get PDFBackground
COVAX was designed to support the discovery, development, and distribution of COVID-19 vaccines globally, at scale and pace. This article examines how COVAX promoted vaccine equity and what lessons can be learnt.
Methods
Informed by a scoping review of lessons learnt from GHPs, we reviewed 109 documents related to COVAX and other GHPs and conducted 23 key informant interviews with representatives from GHPs, civil society, academia, and the private sector. Data were synthesised thematically using Rushton and Williams's framework.
Results
Data showed how the global health policy context shaped COVAX, with experience with Gavi and CEPI influencing its governance structure. We highlighted weaknesses in transparency and accountability, limited engagement with civil society organisations [CSO] and LMIC stakeholders, contested policy debates (e.g., different framing) and paradigms (e.g., prioritising technical and financial over political solutions).
Conclusions
COVAX largely replicated existing GHP approaches, subsidising research and development and then paying for resulting discoveries. While recognising how this reflects global power structures, in the inevitable next global health crisis, the international health community must advocate for greater LMIC and CSO involvement in decision-making, sharing of intellectual property and technology transfer, and rebalancing of flows of innovation costs and benefits to a broader range of actors across public and private sectors
Securing Bangladesh's nuclear future: is the regulated asset base model the answer to address project corruption?
Get PDFBangladesh's goal of achieving high-income status by 2041 requires dependable, low-emission, and affordable energy. With near-universal grid coverage and increasing demand, nuclear energy is a strategic asset for long-term baseload supply. However, the existing financing model, typified by the country's most expensive $12.65 billion Rooppur project which is 90% Russian loan funded, creates national fiscal strain, inflated costs, and systemic corruption risks. The regulated asset base (RAB) model, a framework in utility regulation, offers a viable alternative. By distributing a small levy among Bangladesh's roughly 37 million electricity bill payers, the RAB model can mobilize significant low-cost capital. This reduces reliance on foreign debt and enforces disciplined, transparent project management from the start. This perspective article expects that implementing a RAB model for future nuclear projects in Bangladesh would potentially reduce corruption risks, attract healthy international competition, and lower the ultimate cost of electricity. Our analysis references global examples, specifically the United Kingdom's Sizewell C and Thames Tideway Tunnel projects, and presents a Bangladesh-specific framework. Strengthening the capacity and independence of local regulator (Bangladesh Energy Regulatory Commission [BERC]) is essential to this shift, acting as the guarantor for both investors returns and consumer protection. The RAB model provides Bangladesh an alternative path to energy security, fiscal prudence, and clean power, provided immediate regulatory reform is adopted
No-Code ML pipeline development: Leveraging knowledge graphs and language models
Get PDFConstructing machine learning (ML) pipelines is challenging for non-ML experts due to various tasks and methods. Despite several no-code tools, their ML catalogs remain difficult to navigate. To address these challenges, we present an interactive system that simplifies ML pipeline creation through a graphical user interface (GUI) powered by ExeKGLib , a knowledge graph (KG)-based ML framework. The GUI features a drag-and-drop interface, allowing users to design ML workflows visually without coding. In addition, a large language model (LLM)-powered assistant provides context-aware recommendations for selecting pipeline steps from the ExeKGLib graph. We also utilize ontologies and semantic validation to ensure logical dependencies within the pipeline, guaranteeing usability and correctness. The resulting pipelines are automatically translated into executable KGs and executed by ExeKGLib. We demonstrate the system’s capabilities through a detailed walkthrough, highlighting its role in streamlining ML workflow creation and execution. This demo showcases the synergy between ontologies, KGs, and LLM-powered recommendations, democratizing ML pipeline development for both experts and non-experts
Micro-explosion and recycling of an iron-ethanol-kerosene slurry fuel
Get PDFMetallic iron is explored as a dual-purpose energy carrier and material feedstock by formulating a kerosene-based iron–ethanol slurry that serves both as a micro-explosive fuel where each droplet undergoes rapid internal bubble growth and fragments into many smaller droplets and as a source of recyclable iron. Single-droplet combustion experiments (with 30 wt% iron particles in kerosene + 5 wt% ethanol) demonstrate novel micro-explosion-driven combustion behavior. The addition of ethanol markedly enhances combustion, nearly quadrupling the burning rate and halving the burnout time compared to kerosene alone. Iron particle size is shown to govern the combustion mode: micron-scale iron produces intense, disruptive micro-explosions (with droplet fragmentation rates up to ∼20,000 sec⁻¹) leading to complete burnout in as little as 0.3 s, whereas nano-iron yields more controlled burning (∼1,700 sec⁻¹). Crucially, the hydrocarbon slurry provides an in-situ antioxidant effect, in the sense that the surrounding kerosene liquid acts as a protective barrier that separates the iron particles from oxygen, delaying iron oxidation during combustion and enabling non-oxidative storage of the metal fuel. Following combustion, over 90% of the iron oxide byproduct is recovered and regenerated into metallic iron via hydrogen reduction. The reduced iron is then compacted by Field-Assisted Sintering Technology (FAST), yielding dense iron compacts with fine microstructure and a Vickers hardness of ∼165 HV approximately twice that of conventional pure iron (70–90 HV). This integrated combustion–reduction–sintering cycle highlights a circular iron loop in which the fuel itself becomes a high-value product. The findings showcase a sustainable, energy-efficient metal fuel platform that couples fire-driven micro-explosion phenomena with advanced materials processing, pointing to new opportunities in carbon-free combustion, functional material fabrication, and pyrotechnic applications
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