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Two distinctions about world-relative truth
No full textThe distinction between truth in and truth at a possible world plays a significant role in many debates in modal metaphysics. In this note, I argue that there are two radically different ways of making the distinction precise. Moreover, I argue that the differences matter, showing how they differently constrain the modal metaphysics of properties and propositions
Zebra stripes:the questions raised by the answers
No full textMultiple hypotheses have been suggested to explain why the three zebra species (Equus quagga, E. grevyi and E. zebra) are striped. We review how well these theories explain the nature (rather than simply the existence) of the stripes. Specifically, we explore how well different theories explain (i) the form of zebra stripes (especially on different body parts), (ii) stripe variation between zebra populations and among species, and (iii) the lack of striping in other equids or other large mammalian herbivores. The main hypotheses discussed during the last decade are the deterrence of biting flies, thermoregulation through stripe‐generated air movement, and three anti‐predation hypotheses: crypsis to avoid detection; dazzle colouration to confuse pursuers; and interspecies signalling to encourage protective mixed‐species herding. Our evaluation suggests that these theories struggle to explain all aspects of variation in striping. For each theory we identify where through logical reasoning or empirical data, the theory is unable to account for an aspect of variation, or whether information is currently lacking. In the latter case we offer concrete suggestions for the types of empirical study that would be most useful. Deterrence of biting flies is the theory that currently has strongest empirical support, but this theory alone struggles to explain why striping occurs so strongly in zebra but not in other African mammals, and the distribution of stripes across the body. These aspects can be explained by the interspecies signalling theory, but this theory has not been empirically evaluated. We suggest how future studies could best utilise our framework to close the most pressing knowledge gaps in our understanding of this iconic example of animal colouration
Missing spectral weight in a heavy-fermion system far above Néel temperature
No full textThe competition between the Kondo spin-screening effect and the Ruderman-Kittel-Kasuya-Yosida (RKKY) interaction in heavy-fermion systems drives the quantum phase transition (QPT) between the magnetically ordered and the heavy-Fermi-liquid ground states. Despite intensive investigations of heavy quasiparticles on the Kondo-screened side of the QPT and of their breakdown at the quantum critical point, the magnetically ordering side has not systematically been studied. Using terahertz time-domain spectroscopy, we report a suppression of the Kondo quasiparticle weight in CeCu6−Au samples on the antiferromagnetic (AFM) side of the QPT at temperatures as much as two orders of magnitude above the Néel temperature N. With our systematic investigations into the high-temperature, paramagnetic region on the AFM side of the phase diagram of CeCu6−Au, i.e., with = 0.2, 0.3, and 0.5, we show that the suppression results from a quantum frustration effect induced by the temperature-independent RKKY interaction. Hence, our results emphasize that, in addition to critical fluctuations, the RKKY interaction may play an important role in the quantum-critical scenario
To hoard or not to hoard?:Political uncertainty and corporate cash holdings in emerging Asian economies
No full textThis study aims to examine the impact of political uncertainty on corporate cash holdings across eight Asian emerging economies from 1990 to 2023, using data on national elections and corporate financial data. We focus on two distinct electoral systems: a presidential or legislative electoral system (in Indonesia, South Korea, Malaysia, the Philippines, Singapore, Taiwan, and Thailand) and an assembly-elected presidential system (in the People’s Republic of China), to explore how these systems influence corporate cash holdings. Using fixed effects regressions, the study estimates the sensitivity of cash holdings to cash flows during election periods, showing that cash holdings vary not only by electoral system but also by firm size. The results show that firms in presidential or legislative systems exhibit higher cash flow sensitivity during elections, while firms in the assembly-elected system (China) show negative sensitivity. In addition, this study presents an in-depth examination of close election results and coup d’état events, studying their impacts on corporate cash-holding strategies. These findings show how elections shape corporate financial strategies, contributing to the literature on political uncertainty and its differential impacts on corporate behaviour across different political contexts
Immune response to MVA-BN vaccination for Mpox:current evidence and future directions
No full textThe 2022 global mpox outbreak, caused by clade IIb of the monkeypox virus (MPXV), prompted emergency use authorisation of the Modified Vaccinia Ankara–Bavarian Nordic (MVA-BN) vaccine, previously approved for smallpox prevention. Understanding immune responses to the MVA-BN vaccine is critical to inform both current and future mpox vaccine policy, particularly amid reports of breakthrough infections in vaccinated persons, uncertainty about the durability of vaccine-induced protection, and the emergence of further outbreaks of mpox from different viral clades, including the clade I-driven public health emergency of international concern. MVA-BN elicits binding and neutralising antibody, memory B cells, and T cell responses. Immune responses vary by host factors, prior orthopoxvirus exposure, and dosing regimens. While seroconversion is generally robust, circulating antibody titres often wane rapidly, particularly in vaccinia-naïve and/or immunocompromised individuals, including people with HIV. Vaccine-induced neutralising antibody responses to MPXV are frequently lower than to vaccinia virus, and their role in protection remains ill-defined. In contrast, T cell responses appear more sustained and may support long-term immunity in the absence of persistent antibody titres. This narrative review synthesises current evidence on the immunogenicity and durability of MVA-BN vaccination, highlights challenges in assay interpretation, and outlines key research priorities, including the need to explore correlates of protection, booster strategies, and next-generation vaccine design
Bands, beets & berries:a quantum study of natural dyes for solar cells
No full textDye-sensitised solar cells (DSSCs) offer a sustainable alternative to silicon-based photovoltaics, but widespread adoption is hindered by the cost and scarcity of mainstream dyes. This study investigates the viability of a selection of natural pigments; pelargonidin, betanin, lutein, quercetin, and copper chlorophyllin A as low-cost, sustainable sensitisers for DSSCs. Using density functional theory (DFT) and time-dependent DFT (TD-DFT), the electronic structures, UV-Vis absorption profiles, and electrostatic potential (ESP) maps of each dye were evaluated and compared to the benchmark N3 dye. Copper chlorophyllin A emerged as the most promising candidate, exhibiting strong visible light absorption, favourable frontier orbital alignment, and robust anchoring potential to TiO₂. Quercetin also showed potential due to favourable electrostatic characteristics and photostability, though its absorption is UV-weighted. The findings support the feasibility of locally sourced, natural dyes for DSSC application, and suggest co-sensitisation as a strategy to broaden absorption and improve performance
Weight-bearing pain and implant migration, progressive radiolucencies, radiolucency more than 2 mm and subsidence on radiographs and CT are generally accepted criteria for knee arthroplasty loosening:an international Delphi consensus study
No full textPurpose: Establishing the diagnosis of loosening in total or unicondylar knee arthroplasty remains a challenge with different clinical and radiological signs evaluated in study designs with high risk of bias, where few or incomplete criteria are formulated for establishing the diagnosis of implant loosening. This study aimed at evaluating the variability between different clinical and radiological criteria and establish a consensus regarding clinical and radiological criteria for the diagnosis of knee arthroplasty loosening.Methods: Highly specialized knee surgeons focusing on revision arthroplasty were invited to take part in an international panel for a Delphi consensus study. In the first round, the participants were asked to state their most important clinical and radiological criteria for implant loosening. In a second round, the panel's agreement with the collected criteria was rated on a 5-point Likert scale (1-5). High variability was defined by receiving at least one score each indicating complete disagreement and complete agreement. Consensus was established when over 70% of participants rated a criterion as 'fully agree' (5) or 'mostly agree' (4).Results: High variability was observed in 56% of clinical criteria and 38% of radiological criteria. A consensus was reached on one clinical (weight-bearing pain [82%]) and four radiological criteria, that is, implant migration, progressive radiolucencies, subsidence and radiolucencies >2 mm on X-ray or computed tomography (CT) (84%-100%).Conclusion: Amongst specialized knee revision surgeons, there is high variability in clinical and radiological criteria that are seen as important contributing factors to diagnosis of knee implant loosening. A consensus was reached on weight-bearing pain as clinical criterion and on implant migration, progressive radiolucencies, subsidence and radiolucencies of more than 2 mm on X-ray or CT as radiological criteria. The variability rates observed, along with the criteria that reached consensus, offer important insights for the standardization of diagnostic protocols.Level of evidence: Level V.</p
Insights into biomimetic system–ligand interaction of substituted isophthalic acid:a functionality induced photophysical study
No full textThe present article attempts to interpret the modulation of photophysical properties of isophthalic acid (IPA) through its amino [5-amino isophthalic acid (5-amino IPA)] and azido [5-azido isophthalic acid (5-azido IPA)] substituted derivatives which are chemically potent organic ligands. The ground state structure–reactivity correlation of 5-amino IPA and 5-azido IPA has been deciphered through computational studies. The computed energetics show significant interaction feasibility of the substituted ligand systems with the biomimetic systems which is further validated experimentally. The binding interaction of the probes with oppositely polarized functionalization is studied to be significant with cetyltrimethylammonium bromide (CTAB) and bovine serum albumin (BSA) with the amino functionalized derivative having a comparatively stronger binding constant value. The steady-state absorption and fluorescence study establish significant modification of polarity of the heteronuclear probes. The micro polarity study in water–dioxane mixtures enables determination of polarity of 5-amino IPA in CTAB and BSA unlike 5-azido IPA. Presence of an overlapping region between the emission spectrum of BSA and the absorption spectrum of the probes as probable donor–acceptor pair are also scrutinized via the steady-state fluorescence studies. The photophysical behavior of 5-amino IPA is observed to be somewhat dissimilar to that of 5-azido IPA
Immersive learning of cerebral visual impairment:understanding vision through dynamic immersive simulations
No full textMany different brain-based impairments of vision can affect how someone experiences the world. Those conditions, called Cerebral Visual Impairments (CVI) are often difficult to explain and understand as each individual has their own unique experience of how they see and how their conditions affect them. However, people with CVI benefit substantially if those close to them understand their condition well enough to know which simple steps will make their world easier to navigate, interpret and understand. This paper summarises efforts to create immersive virtual reality visualisations which help those without CVI to better understand various CVI conditions. Two environments types are explored; classrooms and a climate change museum. A visual interface has been created which simulates various effects of CVI. Through this mechanism the user tailors their experience by selecting different impairments and their level of severity which then reacts dynamically to the environment chosen. Through experiential learning from a perspective of the world differing from their own, users gain exposure to CVI and potentially understand changes they can make to better support those affected. Evaluation and feedback demonstrates the simulation’s effectiveness as a research platform in its ability to help refine understanding of the dynamic nature of the impairments. The simulation is also effecting in establishing change in understanding, potentially leading to broader accessibility standards in schools, public spaces and beyond
Amplifying immersive climate learning
No full textClimate change poses an existential threat to our heritage and the way we live, yet its impacts are still often perceived as distant, which in turn acts as a barrier to achieving the behavioural and societal changes required to solve this emergency. This paper summarises impacts of climate change, psychological barriers to effective action, and how experiential climate learning can help overcome these challenges. Surveys of community perceptions of threats to cultural and natural heritage in Scotland’s Western Isles, and the increasing engagement of heritage practitioners with this emergency point to the power of heritage as a positive actor in the climate crisis. A strategy for using virtual reality to extend experiential climate learning is proposed and evaluated through the creation and deployment of a climate heritage exhibit. The exhibit enables climate impacts and potential climate futures for the Western Isles to be experienced. The workflow used is then applied to global landscapes experiencing climate change. This demonstrates the way that virtual reality can represent the diversity of landscapes impacted by this crisis and enable immersive climate learning experiences