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A new implicit formulation of the enthalpy method using flag updates
No full textIn the computation of problems involving phase changes, numerical approaches formulated on enthalpy offer numerous advantages to ‘front-tracking’ methods where the moving boundary between phases is explicitly tracked. However, due to the piecewise definition of enthalpy, such formulations effectively insert additional nonlinearity into the governing equations, thus adding increased complexity to implicit time-evolution schemes. In this paper, we develop and present a new ‘flag-update’ enthalpy method that crucially results in a linear set of equations at each time step. The equations can then be formulated as a sparse linear system, and subsequently solved using a more efficient inversion process. In a detailed error analysis, and via benchmarking on the classic Stefan problem in 1D and 2D, we show that the flag-update scheme is significantly faster than traditional implicit (Gauss–Seidel SOR) methods. However, speedup does not persist in 3D due to the significant memory and storage manipulations required. This study highlights the need to develop rigorous numerical analysis thresholds on such schemes
II - What can we mean? On practices, norms and pluralisms
No full textLast century, Michael Dummett argued that the principles of intuitionistic logic are semantically neutral, and that classical logic involves a distinctive commitment to realism. The ensuing debate over realism and anti-realism and intuitionistic logic has now receded from view. The situation is reversed in mathematics: constructive reasoning has become more popular in the twenty-first century with the rise of proof assistants based on constructive type theory. In this paper, I revisit Dummett’s concerns in the light of these developments, arguing that both constructive and classical reasoning are recognizable and coherent assertoric and inferential practices
Bayesian networks for network inference in biology
No full textBayesian networks (BNs) have been used for reconstructing interactions from biological data, in disciplines ranging from molecular biology to ecology and neuroscience. BNs learn conditional dependencies between variables, which best ‘explain’ the data, represented as a directed graph which approximates the relationships between variables. In the 2000s, BNs were a popular method that promised an approach capable of inferring biological networks from data. Here, we review the use of BNs applied to biological data over the past two decades and evaluate their efficacy. We find that BNs are successful in inferring biological networks, frequently identifying novel interactions or network components missed by previous analyses. We suggest that as false positive results are underreported, it is difficult to assess the accuracy of BNs in inferring biological networks. BN learning appears most successful for small numbers of variables with high-quality datasets that either discretize the data into few states or include perturbative data. We suggest that BNs have failed to live up to the promise of the 2000s but that this is most likely due to experimental constraints on datasets, and the success of BNs at inferring networks in a variety of biological contexts suggests they are a powerful tool for biologists
The LSE right on Scruton's right:Kenneth Minogue on Roger Scruton's conservatism
No full textThis paper explores the intricate dynamics within postwar British intellectual conservatism, focusing on the critique posed by Kenneth Minogue against Roger Scruton’s conservative philosophy. Roger Scruton noted the fragmentation and marginalization of conservatism in postwar British intellectual circles, attributing it to the pervasive influence of John Stuart Mill’s skepticism toward conservative intellect. Despite this, notable conservative clusters emerged at the London School of Economics under Michael Oakeshott and at Peterhouse College, Cambridge, under Maurice Cowling. These clusters, identified as the LSE Right and the Peterhouse Right, respectively, significantly influenced political and academic discourses despite their small size. This paper examines the significant yet underexplored differences between Minogue, representing the LSE Right, and Scruton, the leading figure of Scruton’s Right. Drawing on Minogue’s personal papers, this study elucidates his critical stance on Scruton’s conservatism. By analyzing Minogue’s critique, this paper contributes to a deeper understanding of the doctrinal divergences within British conservatism and their implications for its future trajectory
Isoselenourea‐catalyzed enantioselective pyrazolo‐heterocycle synthesis enabled by self‐correcting amide and ester acylation
No full textPyrazole heterocycles are prevalent in a wide range of medicinal and agrochemical compounds, and as such, the development of methods for their enantioselective incorporation into molecular scaffolds is highly desirable. This manuscript describes the effective formation of fused pyrazolo-pyridones and -pyranones in high enantioselectivity (up to >99:1 er) via an isoselenourea (HyperSe) catalyzed enantioselective [3 + 3]-Michael addition-cyclization process using readily available pyrazolylsulfonamides or pyrazolones as pronucleophiles and α,β-unsaturated anhydrides as starting materials. Mechanistic analysis indicates an unusual self-correcting reaction pathway involving preferential [1,2]-addition of the pronucleophile to initially generate an intermediate amide or ester that can be intercepted by isoselenourea acylation, leading to productive formation of the fused heterocyclic products with high enantiocontrol. The scope and limitations of this process are developed across a range of examples, with insight into the factors leading to the observed enantioselectivity provided by density functional theory (DFT) analysis
Performing disability in French court ballet
No full textIn response to the valuable ongoing work on disability in the field of early modern English theatre, this article advocates for Disability Studies approaches to early modern French theatre. It examines disabled characters from a range of seventeenth-century French court ballets, with a focus on Le Ballet de la nuit (1653). Modern discussions of the lived experience of disability as performance are brought into conversation with the performance by non-disabled dancers, most of them professionals rather than courtiers, of physical and sensorial disabilities in a theatrical genre that emphasized exceptional physical prowess. It is seen that the practice of cripping up (or disability drag) worked against the reality of disability and promoted a heightened ableist aesthetic. However, it is also argued that the bodily experience of performing disability – sometimes with (seemingly) cumbersome props, awkward prosthetics or concealed limbs – will also have granted the dancers new choreographic opportunities and embodied knowledge. This embodied knowledge was not, of course, the same as that of real disabled people. But the creation of ballets featuring disabled characters performed in disability drag unwittingly hinted at what those works sought to deny: the existence of – and skills involved in – authentic disability dance
'...and the evidence was irrefutable':the politics of evidence in the World Commission on Dams
No full textEvidence-based policy-making increasingly shapes the practice of advisory bodies, including global environmental assessments (GEAs). Advocates point to the power of evidence (particularly, but not only scientific evidence) to improve policy-making. Here we discuss how political considerations shaped evidence-gathering and use within the World Commission on Dams (WCD), a GEA body which was active between 1998 and 2000. We use insights from semi-structured interviews with participants in the WCD process. First, we argue that the WCD shows that the political nature of evidence-gathering has long been important in GEA processes. Despite rhetoric emphasising the objectivity of its evidence base, the WCD's evidence-gathering was permeated by political considerations, for example in convening stakeholders with opposing views, giving evidence an instrumental purpose in widening participation and epistemic authority beyond just information and learning. Second, we show how a diversity of evidence (in form and substantive content) can challenge mainstream views. Contrary to the conventional emphasis on technical and quantitative data in GEA processes, we show how personal engagement with emotionally charged evidence, including that from grassroots sources and participatory processes within the WCD, created a shared understanding among opposing sides
Pagan idols and Christian anxieties in medieval Troy narratives
No full textThis chapter examines the treatment of pagan cult statues as idols in mediaeval Troy narratives. It focuses on the language used to convey the idea of idolatry, ranging from relatively neutral presentations to the explicit rejection of idols and their veneration. The literary emphasis on the wealth lavished on pagan gods and their images, on the physical worship of the images through prostration and sacrifice, and on the demonic forces inhabiting the ‘empty’ images is often mirrored in manuscript illuminations which depict the images as ‘ugly’ figures made of gold and animated by pagan worship. This chapter draws on both visual and literary evidence to highlight the ways in which mediaeval Troy narratives reflect a Christian struggle to appropriate the Greco-Roman past and its narratives, while simultaneously using them to distinguish ancient pagan ritual from contemporary Christian practices and ideals. It argues that mediaeval Troy narratives serve as vehicles for Christian reflections on the concept of idolatry and on Christianity’s complicated relationship with it, as well as vehicles for the perpetuation of religious prejudice by linking paganism and Islam with devil-worship through the charge of idolatry
How the year 2025 changed writing recent Chinese (and world) history
No full textOver the past few years, I have been planning and researching a multi-volume work entitled "A politico-cultural history of the People's Republic of China 1976-2025". However, given the contemporary and and global reach of my book, geopolitical events over the past few months have obliged me to re-assess the historiographical and methodological compass of my work. Here I address why
Designing progressive model elicitation tools to support complex cognitive activities
No full textExternalizations such as sketches and diagrams are effective in helping individuals plan for complex projects and designs. Offloading complex information on a different medium (e.g. paper) frees up cognitive resources for sophisticated thinking. However, there are significant challenges in effectively using externalizations and notations (formalized externalizations). It is difficult to envision formal representations of complex ideas at the beginning and it is also hard to keep track of evolutions within notations. In addition, existing notations may be insufficient or inflexible for our specific purposes. We call instances of such thinking in which humans have to work through complex information and action space as instances of "Progressive Model Elicitation" (PME). We explore ways to support PME processes by presenting a set of design principles and Schematica, a prototype that implements those design principles to support PME. We present illustrative examples of Schematica use to support the process of PME