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Transforming jet flavour tagging at ATLAS
Get PDFJet flavour tagging enables the identification of jets originating from heavy-flavour quarks in proton–proton collisions at the Large Hadron Collider, playing a critical role in its physics programmes. This paper presents GN2, a transformer-based flavour tagging algorithm deployed by the ATLAS Collaboration that represents a different methodology compared to previous approaches. Designed to classify jets based on the flavour of their constituent particles, GN2 processes low-level tracking information in an end-to-end architecture and incorporates physics-informed auxiliary training objectives to enhance both interpretability and performance. Its performance is validated in both simulation and collision data. The measured c-jet (light-jet) rejection in data is improved by a factor of 3.5 (1.8) for a 70% b-jet tagging efficiency, compared to the previous algorithm. GN2 provides substantial benefits for physics analyses involving heavy-flavour jets, such as measurements of Higgs boson pair production and the couplings of bottom and charm quarks to the Higgs boson, and demonstrates the impact of advanced machine learning methods in experimental particle physics
Technical writing across space and time: the challenges of lemmatisation and part-of-speech tagging in the historiographical and medical corpora of (post)classical Greek
No full textDatasets related to the book chapter of the same name in V. Fendel (ed.), Verbal Multi-Word Expressions in Corpus Languages: Data, Methodology, and Analysis. Cambridge: Open Book Publishers. 2026
Grammatical constraints on focus alternatives? The case of gender in Czech
No full textThis paper examines the interaction of grammatical gender and focus in speakers’ linguistic competence and processing. We adopt the theory that analyses focus as the inducement of alternative meanings. Based on previous research on Romanian, we tested whether gender restricts focus alternatives through gender-marked numerals in Czech. However, the results of our acceptability judgement experiment found no effects of gender. We raised the possibility that the effects of gender were located the processing of focus instead. We conducted a speeded acceptability judgment experiment, which found effects of gender but in the opposite direction; gender matched items were less acceptable. Finally, we conducted a probe recognition experiment to examine the representation of focus alternatives in the mind. The results revealed no effects of gender. Overall, the research reported in this paper make us decrease our credence in the hypothesis that gender interacts with focus alternatives
Fractured Brotherhoods: Ethnic Identity in Multi-Ethnic Violent Political Groups
Get PDFThis paper explores the critical role of pre-existing social networks in determining the organizational integration or fragmentation of armed groups, with a particular focus on sub-Saharan Africa. Ethnic networks and structures have historically shaped conflicts in this region, such as the civil wars in Burundi and Nigeria. Although some contemporary armed groups, especially religious extremists in Somalia, Nigeria, and Mali, claim to transcend ethnic identities, maintaining cohesion in ethnically heterogeneous groups remains challenging. Effective socialization of combatants is essential for ensuring homogeneity and commitment, as individuals possess multiple overlapping social and political identities. Implementing socialization methods, such as ideological education, helps unify members and maintain organizational coherence despite diverse backgrounds. However, these efforts often face barriers, and ethnicity can remain a dominant factor. Through interviews with Boko Haram ex-combatants in Northern Nigeria (2019–2023), this study examines when, why, and how ethnicity becomes foregrounded within armed groups, overriding intended supra-identities. The findings reveal that unit leaders’ pathways to leadership and their socialization into Boko Haram are primary determinants of ethnic foregrounding. Leaders promoted without full socialization are more likely to retain ethnic sentiments and exhibit bias toward co-ethnics, influencing reward, punishment, and military operations
Tomographic constraints on the high-energy cosmic neutrino emission rate
Get PDFDespite growing efforts to find the sources of high-energy neutrinos measured by IceCube, the bulk of the neutrinos remain with unknown origins. In this work, we aim to constrain the emissivity of cosmic high-energy neutrinos from extragalactic sources through their correlation with the large-scale structure. We use cross-correlations between the IceCube 10-year data set and tomographic maps of the galaxy overdensity to place constraints on the bias-weighted high-energy neutrino emissivity out to redshift . We test two different models to describe the evolution of neutrino emissivity with redshift, a power-law model , and a model tracking the star formation history, assuming a simple power-law model for the energy injection spectrum. We also consider a non-parametric reconstruction of the astrophysical neutrino emissivity as a function of redshift. We do not find any significant correlation, with our strongest results corresponding to a deviation with respect to a model with zero signal. We use our measurements to place upper bounds on the bias-weighted astrophysical high-energy neutrino emission rate as a function of redshift for different source models. This analysis provides a new probe to test extragalactic neutrino source models. With future neutrino and galaxy data sets, we expect the constraining and detection power of this type of analysis to increase
Molecular driving force of a small molecule-induced protein disorder-order transition
Get PDFThe selectivity and affinity of numerous protein–protein interactions depends upon the folding of intrinsically disordered regions (IDRs) that accompanies complexation. Here we investigate how folding-on-binding of a protein IDR by small molecules is facilitated by synergestic exploitation of interactions with a folded protein region. To this end, the molecular driving forces that underpin ordering of the N-terminal intrinsically disordered ‘lid’ region of the oncoprotein MDM2 by the small molecule AM-7209 were elucidated by a combination of molecular dynamics simulations, calorimetry and NMR measurements. Strikingly, mutations of lid residues distant from the ligand-binding site modulate potency by up to three orders of magnitude. A key requirement for conversion of this IDR into an ordered motif is collective stabilisation of a network of non-polar contacts between a chlorophenyl moiety of AM-7209 and the lid residue I19 to overcome conformational entropy loss associated with folding of the IDR. Our findings underscore the crucial role that protein IDRs can play in drug-resistance mechanisms and expand strategies available to medicinal chemists for ligand optimisation endeavours
On the well-posedness of a nonlocal kinetic model for dilute polymers with anomalous diffusion
Get PDFIn this work, we study a class of nonlocal-in-time kinetic models of incompressible dilute polymeric fluids. The system couples a macroscopic balance of linear momentum equation with a mesoscopic subdiffusive Fokker–Planck equation governing the evolution of the probability density function (PDF) of polymers. The model incorporates nonlocal features to capture subdiffusive and memory-type phenomena. Our main result asserts the existence of global-in-time large-data weak solutions to this nonlocal system. The proof relies on an energy estimate involving a suitable relative entropy, which enables us to handle the critical general non-corotational drag term that couples the two equations. Crucial steps in our analysis are the proof of the nonnegativity of the PDF and to establish strong convergence of the sequence of Galerkin approximations. This involves a novel compactness result for nonlocal PDEs. Lastly, we prove the uniqueness of weak solutions with sufficient regularity
Aperiodic parameters of the fMRI power spectrum associate with preterm birth and neonatal age
Get PDFPerinatal period is a critical time for brain development and premature-born children have an elevated likelihood for neurodevelopmental conditions. While strong associations of structural magnetic resonance imaging with preterm birth and post-menstrual age (PMA) have been reported, results with functional MRI (fMRI) have been considerably weaker. Using the task-free neonatal fMRI dataset from the Developing Human Connectome Project (dHCP), we first studied the associations of the aperiodic component of the blood-oxygen-level-dependent (BOLD) signal power spectrum from pre- and postcentral gyri with preterm birth and mapped the associations with PMA, postnatal age, and sex, and found clear differences between preterm and full-term groups, as well as males and females. Second, we used machine learning regression to predict participants' age from the aperiodic parameters of the BOLD signal from 90 cortical and subcortical regions of interest with relatively high accuracy (test R2's 0.20-0.41)
Beijing’s global opposition campaign
Get PDFThe conventional literature on power transitions warns that a rising challenger may seek to dethrone the established power by launching a devastating great-power war. The contemporary international environment, however, differs from that of the past, creating incentives to avoid a major conflagration and instead employ a strategy of amassing international support and improving institutional standing. Given these strategic aims, as a rising power, China is more likely to adopt tactics analogous to a domestic opposition party: promoting an alternative political programme with slogans and manifestos; seeking a greater institutional presence by building support with coalitions and patronage relationships; and using political communications to portray itself positively in contrast to the incumbent power. Based on an examination of three domains of China’s behaviour, this analogy sheds light on the tactics it is using to pursue a greater international leadership role
Rethinking chaı̂ne opératoire: agency and cognition in Bronze Age Aegean pottery production
Get PDFThe aim of this project is to rethink and re-envision the chaîne opératoire approach by considering theories of agency and cognition. I investigate three hypotheses: (1) chaîne opératoire is frequently engaged with only partially, (2) chaîne opératoire can be enhanced by considering theories of agency (ways of doing) and cognition (ways of thinking), and (3) that by incorporating theories of agency and cognition and further re-envisioning the framework we may arrive at a novel approach for the methodological analysis of production processes. This thesis is divided into three parts. In Part One, Leroi-Gourhan’s chaîne opératoire approach is reviewed and the main components are defined. Developments of the chaîne opératoire approach and, in particular, adaptations of the chaîne opératoire approach for archaeology are explored. Archaeological case studies of Bronze Age Aegean pottery are compiled for analysis due to the popularity of the chaîne opératoire approach within this subject as well as pottery’s unique affordances. Upon analysis, I develop a taxonomy of three Use Types of the chaîne opératoire approach. Each Use Type draws on distinct elements of the chaîne opératoire approach. I argue that outdated theories of agency and cognition are at the center of the discrepancies between the significant scope of the framework and its practical use(s). In Part Two, theories of agency and cognition are analyzed. I propose that the significant scope of the framework can be supported by theories of emergent, enactive, relational, co- constructive agency. Thereafter, I develop an avenue for the inclusion of these theories of agency within a chaîne opératoire approach. I then propose that the significant scope of the chaîne opératoire approach can similarly be supported by theories of embodied, enacted, and extended cognition due in part to how closely linked these theories are to process trends and milieus. Following analysis, I propose a singular framework which links these cognitive theories with process trends and milieus. Part Three is the culmination of this work wherein I produce a novel chaîne opératoire approach which accounts for contemporary theories of agency and cognition demonstrated via application to a case study at Zakros. Throughout this project I also develop the visualization of the chaîne opératoire approach. What has historically been imagined as a linear framework, is re-envisioned commensurate with the theoretical amendments proposed. The final proposed framework and visualization effectively link the finite aspects of making with the larger phenomenon of the process of making