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Improving forecasting accuracy at the OBR: submission to the treasury committee enquiry ‘The OBR: 15 years on’
Get PDFThe OBR has made systematic large forecast errors since 2010. Our approach corrects large forecast errors occurring after unexpected shifts. It can be implemented rapidly even if updating a forecasting system is difficult. Illustrated here by improved forecasting of UK productivity relative to OBR
Why The Polyvagal Theory Is Untenable: An international expert evaluation of the polyvagal theory and commentary upon Porges, S.W. (2025). Polyvagal theory: current status, clinical applications, and future directions. Clin. Neuropsychiatry, 22(3), 169-184
Get PDFThirty-nine highly acknowledged experts in the areas of the physiology and the evolution of the vagus nerve and of vertebrate social behavior (many whose works have been cited in the polyvagal theory [PVT] literature as supporting the theory) were invited by the first author to participate as co-authors of this article. They were asked to evaluate the PVT and comment upon an overview of the theory written by its author (Porges, 2025a). All those invited, save one, accepted and co-authored the paper. The dissenting scholar was "unfamiliar with the PVT." This article specifically appraises--based upon the current state of knowledge of autonomic function and vertebrate evolution--several major elements of the PVT, as described in Porges (2025a) and elsewhere. These include: 1) the validity of PVT assumptions that respiratory sinus arrhythmia is a direct measure of the extent of central vagal drive to the heart; 2) PVT characterizations regarding the neuroanatomy and functions of two major brainstem vagal nuclei, the ventrally situated Nucleus Ambiguus and the Dorsal Motor Nucleus of the vagus nerve; 3) PVT assertions regarding the evolution of the vagus nerve; 4) PVT claims about the specificity of mammalian social behavior in relation to nonmammalian vertebrates, and 5) PVT interpretations of earlier seminal physiological literature. All co-authors agree that major tenets of the PVT are not supported by past or current knowledge and, in several instances, are inconsistent with the broader evidence base. Since the topics addressed constitute fundamental premises of the PVT, we conclude that the PVT is untenable, because it is not defensible based on existing neurophysiological and evolutionary evidence. The psychological elements composing the superstructure of the PVT are primarily derived from earlier psychological literature and are neither clarified nor strengthened by PVT constructs that lack evidence. This article does not intend to address alternative explanations about relations between vagal function and psychological processes, although such explanations do exist
Advancing health policy and systems research and analysis: new frontiers, renewed relevance
Get PDFHealth systems are at a crossroads. Globally, health systems are straining under the weight of responding to persistent and emergent challenges. Uncertainties in health financing, service delivery, new technologies and disease burdens are hindering health systems abilities to maximize collective and scaled action to achieve health equity and social justice. In March 2025, a group of health policy and systems experts were convened by an organization, to consider the ‘new frontiers’ of the field in the context of shifting global and national landscapes. Deliberations centred on the critique that health policy and systems research (HPSR) need to restate its core foundations, better articulate its impacts in real health systems and policy processes, while defining its role within or apart from ‘global health’. Six frontiers were identified: new institutional forms of HPSR beyond academic settings; more fully theorized and hypothesized studies that go beyond descriptive; more applies systems thinking; new educational models to support analysis, networking and systems leadership; more domestic financing for HPSR; and genuine engagement with a new set of health system development actors. For HPSR to remain relevant, strengthening the science and practice of how diverse actors engage to bring about collective action for health equity and social justice is imperative. The current global geopolitical, financing, and planetary shifts, while critical, present an opportunity for these new frontiers in HPSR to deepen the impact of the field
Was capital expensive in the colonial countryside? The view from Uttar Pradesh
Get PDFWas capital expensive in Colonial India? This paper addresses this question by examining rents and land prices between 1800 and 1939 in the United Provinces (now Uttar Pradesh) in Northern India. I calculate four different estimates of the rate of return to landownership, which by arbitrage should be linked to the rate of return on land-like capital investment more generally. All show a major decline in real interest rates over the 19th century. By 1870, those used to price landownership were usually less than 5 per cent. By 1900, the rent (net of tax) to price ratio was much the same as in England. The rate of return to land was not far from formal sector interest rates: financial markets were integrated. Over the long run there was rather modest real rent growth. Land prices skyrocketed, however, because of falling interest rates. These results suggest that private property rights were expected to be secure and that capital was not expensive, at the relevant margin for land-like investments, in Colonial India: low investment was due to a low demand for it rather than an expensive supply
Layered double hydroxide-based catalysts for thermocatalytic CO2 conversion
Get PDFThis thesis explores the development of layered double hydroxide (LDH)-based catalysts for the direct thermocatalytic conversion of carbon dioxide (CO2) to value-added chemicals, specifically methanol and dimethyl ether (DME). The research contributes to the advancement of low-cost, efficient catalysts designed to utilise CO2 as a carbon feedstock, thereby supporting defossilisation strategies and facilitating the transition of the chemical industry from a linear to a circular economy.Chapter 1 provides the contextual foundation for the work by outlining the current challenges and opportunities in CO2 utilisation. It examines the thermodynamic and catalytic limitations associated with CO2 conversion, with a particular focus on the production of methanol and DME, two high-value chemicals with a wide range of applications. The chapter introduces LDHs as catalyst precursors and discusses how hierarchical structures such as core-shells can enhance catalyst performance.In Chapter 2, the synthesis and characterisation of a bifunctional [email protected] core-shell catalyst, derived from an LDH-coated zeolite precursor, for the direct conversion of CO2-to-DME (CTD). Catalytic testing was carried out in a fixed-bed reactor operating at 3 MPa, between 220 – 300 °C and a weight hourly space velocity (WHSV) of 44,000 mL/gcat·h (CO2/H2/N2 24:72:4). The bifunctional catalyst demonstrated high DME productivity with a maximum space time yield (STYDME) of 0.72 gDME/gcat·h. Further experiments revealed the importance of an oxidising calcination atmosphere in activating the catalyst for efficient CTD conversion.Chapter 3 investigates the impact of residual sodium content and the ZSM-5:LDH ratio on the performance of the core-shell catalyst. Although sodium had a minimal influence on the methanol productivity of the LDH-derived Cu1.3ZnAl catalyst (0.27 – 0.29 g_(CH_3 OH)/gcat·h), it had a considerable impact on the performance of the bifunctional catalysts. Results from CO2 hydrogenation experiments revealed that [email protected], with a 1:1 ZSM-5:LDH ratio, remained the most active catalyst under the conditions of P = 3 Mpa, T = 260 – 340 °C, WHSV = 18,000 mL/gcat·h, and CO2/H2/N2 = 24:72:4. These findings underscore the importance of precise control over the core-shell precursor morphology in determining the catalytic performance of the resulting catalyst.Chapter 4 describes the synthesis and characterisation of a series of Zr-incorporated hydrotalcite-like materials to investigate the role of Zr as a promoter for Cu1.3ZnAl. CO2 hydrogenation tests of Zr-incorporated Cu1.3ZnAl led to improved CTM activity at higher Zr loadings (CZA-Zr0.5 = 0.33 g_(CH_3 OH)/gcat·h, CZA-Zr0.75 = 0.33 g_(CH_3 OH)/gcat·h). Subsequently, Zr was incorporated into the in-situ¬ coprecipitation of the core-shell. The remainder of the chapter discusses its performance relative to the original [email protected] core-shell catalyst.Chapter 5 provides a summary of the key findings presented throughout the thesis and outlines potential directions for future research. Chapter 6 describes the analytical techniques and synthesis methods used in the Chapters 2 to 4. Additional data and supplementary information referenced in the main text are included in the Appendices
Joint moments of characteristic polynomials from the orthogonal and unitary symplectic groups
No full textWe establish asymptotic formulae for general joint moments of characteristic polynomials and their higher-order derivatives associated with matrices drawn randomly from the groups and in the limit as . This relates the leading-order asymptotic contribution in each case to averages over the Laguerre ensemble of random matrices. We uncover an exact connection between these joint moments and a solution of the -Painlevé V equation, valid for finite matrix size, as well as a connection between the leading-order asymptotic term and a solution of the -Painlevé III equation in the limit as . These connections enable us to derive exact formulae for joint moments for finite matrix size and for the joint moments of certain random variables arising from the Bessel point process in a recursive way. As an application, we provide a positive answer to a question proposed by Altug et al. [Quarterly Journal of Mathematics, 65 (2014), 1111--1125]
Scale-separated AdS vacua and holography
Get PDFThis thesis explores potential holographic duals of AdS vacua in string theory with a parametric separation between the AdS curvature scale and the scale of the internal dimensions. Our primary focus is on the four-dimensional vacua constructed by DeWolfe, Giryavets, Kachru, and Taylor (DGKT, 2005). We analyze the spectrum of low-lying scalar operators and find a universal structure: all dimensions are integer-valued, independent of flux choices or intersection numbers. For similar three-dimensional scale-separated AdS vacua, we find that integer conformal dimensions are not always present there. We explain how integer dimensions come together with exotic shift symmetries for the scalar fields that depend polynomially on spacetime coordinates. Additionally, we observe how vacua with integer dimensions seem to correspond to a simplified holographic brane set-up, where large N scalings can be derived in a simple way from the near-horizon geometry, similarly to the well-understood Freund-Rubin vacua. Finally, we present a systematic method for deriving the holographic brane setup from the flux-induced scalar potential and apply this framework to several examples, including the DGKT model
A Short Report on Melanocyte/Melanoma Culture, Senescence, and Reproducibility
Get PDFAt the 2025 ESPCR (European Society for Pigment Cell Research) meeting in Erlangen, a workshop on “Pigment Cell Models: Sensitivity, Innovation, and the Challenges of Cell Culture” brought together researchers to discuss technical, methodological, and reproducibility issues in culturing melanocytes, keratinocytes, fibroblasts, and melanoma cells. The discussion between experts in the field highlighted key and recurrent pitfalls affecting experimental outcomes, including low‐density seeding, temperature fluctuations, over‐passaging, and mycoplasma contamination, as well as sources of variability arising from media composition, batch effects, and environmental conditions. Importantly, the workshop distinguished between practices supported by evidence and consensus‐based guidance derived from collective expert experience. Species‐ and donor‐specific differences, especially between human, mouse, and zebrafish melanocyte models, were identified as additional major determinants of experimental variability. Emerging systems, including human and mouse pluripotent stem cell (PSC)‐derived melanocytes, as well as avian and zebrafish melanoma lines, were discussed for their complementary mechanistic and translational value. Overall, the workshop concluded that transparent documentation, explicit reporting standards, and shared best practices are essential to improve reproducibility and further advance pigment cell research
The DREAMS START intervention for sleep in dementia: Long‐term follow‐up of a randomized controlled trial
Get PDFINTRODUCTION: Sleep disturbances are common and distressing for people with dementia and their family caregivers, with limited treatment options. The DREAMS START (Dementia RElAted Manual for Sleep; STrAtegies for RelaTives) multi‐component intervention for sleep disturbance in people at home with dementia is clinically and cost‐effective at 8 months. In this long‐term follow‐on study, we assessed 2‐year clinical effectiveness. METHODS: We recruited dyads of people with dementia and their family caregivers from community settings, for a two‐arm, multi‐center, single‐blind, parallel‐arm, superiority trial with the primary outcome Sleep Disorders Inventory (SDI). Analyses were intention to treat. RESULTS: We randomized 377 dyads, 189 to treatment‐as‐usual (TAU) and 188 to intervention; 177 dyads (46.9%) were followed up at 24 months. Two‐year adjusted mean SDI score was lower in the intervention arm than TAU (−5.40; 95% CI −9.14 to −1·67; p = 0·005). DISCUSSION: In this follow‐on study we demonstrate 2‐year improvement in sleep disruption for people with dementia. DREAMS START has potential for delivery at scale
Where Do Stars Explode in the ISM?—The Distribution of Dense Gas around Evolved Massive Stars in M33
Get PDFThe effect of supernovae (SNe) on star formation in the interstellar medium (ISM) depends sensitively on where SNe explode with respect to ISM clouds. Observationally, SN ISM environments characterized by spatially resolved gas maps can empirically guide the placement of SNe in subgrid models, but unfortunately such measurements remain scarce, as SNe are rare and often distant. Here we demonstrate a new approach—mapping the ISM around evolved massive stars that are soon to explode. These provide a substantially larger sample of “explosion sites” (than just historical SNe) in nearby galaxies that have high-resolution atomic and molecular ISM maps from the Jansky Very Large Array and Atacama Large Millimeter/submillimeter Array. We demonstrate this technique in the well-resolved Local Group spiral M33 by analyzing the 50 pc scale projected ISM densities around red supergiants (RSGs; 8–30 M⊙ stars) Wolf–Rayet stars (W-Rs; >30M⊙ stars), and supernova remnants. We find a mass-dependent correlation between stars and gas clouds, with at least 45% of W-Rs and up to 77% of RSGs having no detectable H2 at their pixel locations. In the sample with H2 detections, we find that more-massive younger progenitors are coincident with denser gas. We show that the density distributions for stars >15 M⊙ are statistically distinct from random alignment of stars and gas in M33. Our work provides the first observationally derived estimate of the fraction of the SN-producing stellar population correlated with ISM density peaks. We demonstrate how this can be compared with galaxy simulations, and advocate similar comparisons to the community for constraining subgrid models