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Universal filtered quantizations of nilpotent Slodowy slices
Every conic symplectic singularity admits a universal Poisson deformation and a universal filtered quantization, thanks to the work of Losev and Namikawa. We begin this paper by showing that every such variety admits a universal equivariant Poisson deformation and a universal equivariant quantization with respect to a reductive group acting on it by C X-equivariant Poisson automorphisms. We go on to study these definitions in the context of nilpotent Slodowy slices. First, we give a complete description of the cases in which the finite W -algebra is a universal filtered quantization of the slice, building on the work of Lehn–Namikawa–Sorger. This leads to a near-complete classification of the filtered quantizations of nilpotent Slodowy slices. The subregular slices in non-simply laced Lie algebras are especially interesting: with some minor restrictions on Dynkin type, we prove that the finite W -algebra is a universal equivariant quantization with respect to the Dynkin automorphisms coming from the unfolding of the Dynkin diagram. This can be seen as a non-commutative analogue of Slodowy’s theorem. Finally, we apply this result to give a presentation of the subregular finite W -algebra of type B as a quotient of a shifted Yangian.</p
Skin hepcidin initiates psoriasiform skin inflammation via Fe-driven hyperproliferation and neutrophil recruitment
Psoriasis is a multifactorial, chronic inflammatory skin disease with unresolved questions on its primary events. Iron overload has been described in the epidermis of psoriasis patients, but its relevance remains unknown. We found that the key iron regulatory hormone hepcidin was highly expressed in the epidermis of psoriasis patients, especially the pustular variants resistant to treatments. In a murine model of acute skin inflammation, keratinocyte-derived hepcidin was required for iron retention in keratinocytes, leading to hyperproliferation of the epidermal layer and neutrophil recruitment, two main features of psoriatic skin lesions. Keratinocytes overexpressing hepcidin were sufficient to elicit these psoriasiform features in a transgenic mouse model. Furthermore, transcriptome analysis of these keratinocytes revealed canonical pathways found in human psoriasis, pointing to a causal role for hepcidin in the pathogenesis of the disease. Altogether, our data suggest that hepcidin could be an actionable target for skin psoriasis treatment, in addition to current therapeutics, or targeted as maintenance therapy during remission to prevent recurrence.</p
Pursuing family justice before, during, and after the COVID-19 pandemic:the changing role of Legal Companions and the new invisibility of unmet legal need
This article provides three snapshots of family justice – pre-pandemic, during national lockdown, and as England settled into a ‘new normal’ of hybrid justice processes. It does so by drawing upon focus group discussions with Legal Companions working in the family court, who support litigants in person in the manner of McKenzie Friends. This research points to the interacting influences of policy reform and pandemic management, such that the emergency measures introduced by the latter entrenched the longer term changes sought by the former. The study seeks to capture the compound effects of these shifts, including a deepening of social inequality, a sharp reduction in access to justice, and the decreased visibility of those who are in greatest need of support. As part of this, we explore the diffuse benefits of the emotional support provided by Legal Companions to those representing themselves in private family law cases and identify key changes to this role in the new world of online and hybrid justice
A lanthanide-rich kilonova in the aftermath of a long gamma-ray burst
Observationally, kilonovae are astrophysical transients powered by the radioactive decay of nuclei heavier than iron, thought to be synthesized in the merger of two compact objects 1–4. Over the first few days, the kilonova evolution is dominated by a large number of radioactive isotopes contributing to the heating rate 2,5. On timescales of weeks to months, its behaviour is predicted to differ depending on the ejecta composition and the merger remnant 6–8. Previous work has shown that the kilonova associated with gamma-ray burst 230307A is similar to kilonova AT2017gfo (ref. 9), and mid-infrared spectra revealed an emission line at 2.15 micrometres that was attributed to tellurium. Here we report a multi-wavelength analysis, including publicly available James Webb Space Telescope data 9 and our own Hubble Space Telescope data, for the same gamma-ray burst. We model its evolution up to two months after the burst and show that, at these late times, the recession of the photospheric radius and the rapidly decaying bolometric luminosity (L bol ∝ t −2.7±0.4, where t is time) support the recombination of lanthanide-rich ejecta as they cool.</p
Statistical critical reactive maintenance characterisation for digital twin implementation in universities
Purpose: Facilities management (FM) plays a key role in the performance of businesses to ensure the comfort of users and the sustainable use of natural resources over operation and maintenance. Nevertheless, reactive maintenance (RM) services are characterised by delays, waste and difficulties in prioritising services and identifying the root causes of failures; this is mostly caused by inefficient asset information and communication management. While linking building information modelling and the Internet of Things through a digital twin has demonstrated potential for improving FM practices, there is a lack of evidence regarding the process requirements involved in their implementation. This paper aims to address this challenge, as it is the first to statistically characterise RM services and processes to identify the most critical RM problems and scenarios for digital twin implementation. The statistical data analytics approach also constitutes a novel practical approach for a holistic analysis of RM occurrences. Design/methodology/approach: The research strategy was based on multiple case studies, which adopted university campuses as objects for investigation. A detailed literature review of work to date and documental analysis assisted in generating data on the FM sector and RM services, where qualitative and statistical analyses were applied to approximately 300,000 individual work requests. Findings: The work provides substantial evidence of a series of patterns across both cases that were not evidenced prior to this study: a concentration of requests within main campuses; a balanced distribution of requests per building, mechanical and electrical service categories; a predominance of low priority level services; a low rate of compliance in attending priority services; a cumulative impact on the overall picture of five problem subcategories (i.e. Building-Door, Mechanical-Plumbing, Electrical-Lighting, Mechanical-Heat/Cool/Ventilation and Electrical-Power); a predominance of problems in student accommodation facilities, circulations and offices; and a concentration of requests related to unlisted buildings. These new patterns form the basis for business cases where maintenance services and FM sectors can benefit from digital twins. It also provides a new methodological approach for assessing the impact of RM on businesses. Practical implications: The findings provide new insights for owners and FM staff in determining the criticality of RM services, justifying investments and planning the digital transformation of services for a smarter provision. Originality/value: This study represents a unique approach to FM and provides detailed evidence to identify novel RM patterns of critical service provision and activities within organisations for efficient digitalised data management over a building’s lifecycle.</p
On the development and analysis of coupled surface-subsurface models of catchments. Part 3. Analytical solutions and scaling laws
The objective of this three-part work is to formulate and rigorously analyse a number of reduced mathematical models that are nevertheless capable of describing the hydrology at the scale of a river basin (i.e. catchment). Coupled surface and subsurface flows are considered. In this third part, we focus on the development of analytical solutions and scaling laws for a benchmark catchment model that models the river flow (runoff) generated during a single rainfall. We demonstrate that for catchments characterised by a shallow impenetrable bedrock, the shallow-water approximation allows a reduction of the governing formulation to a coupled system of one-dimensional time-dependent equations for the surface and subsurface flows. Asymptotic analysis is used to derive semi-analytical solutions for the model. We provide simple asymptotic scaling laws describing the peak flow formation, and demonstrate its accuracy through a comparison with the two-dimensional model developed in Part 2. These scaling laws can be used as an analytical benchmark for assessing the validity of other physical, conceptual or statistical models of catchments.</p
Decentralized Funding of Public Goods in Blockchain System:Leveraging Expert Advice
Public goods projects, such as open-source technology, are essential for the blockchain ecosystem's growth. However, funding these projects effectively remains a critical issue within the ecosystem. Currently, the funding protocols for blockchain public goods lack professionalism and fail to learn from past experiences. To address this challenge, our research introduces a human oracle protocol involving public goods projects, experts, and funders. In our approach, funders contribute investments to a funding pool, while experts offer investment advice based on their expertise in public goods projects. The oracle's decisions on funding support are influenced by the reputations of the experts. Experts earn or lose reputation based on how well their project implementations align with their advice, with successful investments leading to higher reputations. Our oracle is designed to adapt to changing circumstances, such as experts exiting or entering the decision-making process. We also introduce a regret bound to gauge the oracle's effectiveness. Theoretically, we establish an upper regret bound for both static and dynamic models and demonstrate its closeness to an asymptotically equal lower bound. Empirically, we implement our protocol on a test chain and show that our oracle's investment decisions closely mirror optimal investments in hindsight
Cyber-diplomacy:The Emergence of a Transient Field
It is only in the last two decades that states have started to focus on the need to use traditional diplomatic means in discussions surrounding cyber-policy. This article explores how these discussions have been progressively ‘diplomatised’. Diplomatisation is proposed in this article as a process which involves external and internal dynamics of institutionalisation and positioning, both of which are essential for the successful creation of a new diplomatic field. Understanding the emergence of cyber-diplomacy is crucial to recognise the successes, frustrations and opportunities associated with the (lack of) regulation when it comes responsible state behaviour in this domain. This article does so based on 40 interviews conducted with diplomats and experts involved in the emergence of cyber-diplomacy. It looks at the idiosyncratic evolution of this field within specific nation states as well as overall developments at the international level, particularly within the context of the United Nations
Dataset for "Calorie restriction-induced leptin reduction and T-lymphocyte activation in blood and adipose tissue in men with overweight and obesity"
Raw data composed of adipose tissue ex vivo secretion, adipose tissue macrophage abundances, adipose tissue T cell counts and proportions, T cell activation marker expression and leptin and insulin receptor expression in adipose tissue, peripheral blood T cell counts and proportions, T cell activation marker expression and leptin and insulin receptor expression in peripheral blood, peripheral blood monocyte proportions and expression of leptin and insulin receptors, adipose tissue metabolic gene expression, serum metabolic and inflammatory protein concentrations, basic participant anthropometrics, dietary energy intake and daily expenditure, DEXA-derived body composition, OGTT results, and energy intake prescriptions during a 3 day 50 % calorie restriction protocol in 12 overweight and obese males