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DiICz MR-TADF emitters as potent energy transfer photocatalysts
No full textFunding: The authors thank the European Union H2020 research and innovation program for the funding under the Marie S. Curie Grant Agreement (PhotoReAct, No. 956324), and EPSRC for financial support (EP/W522259/1, EP/W007517/1 and EP/M02105X/1).Photoinduced energy transfer (PEnT) reactions are a subset of photochemical reactions that involve the indirect photoactivation of substrates following an energy transfer from a photoexcited sensitizer/photocatalyst. Examples of PEnT reactions include E/Z isomerizations, [2 + 2] cycloadditions, and sigmatropic shifts. Here we introduce a family of diindolocarbazole (DiICz) multi-resonant thermally activated delayed fluorescent (MR-TADF) photocatalysts (PCs), DiICztBu4 , DiICzMes4 , DiICztBuCz4 , and DiICztBuDPA4 , which have relatively high triplet energies (ET). We cross-compare their photocatalytic behavior and that of relevant literature reference PCs' in five distinct PEnT reactions. We demonstrate that the use of the DiICz PCs consistently leads to more rapid reaction rates and higher yields compared to the widely used 4CzIPN . DiICztBu4 , DiICzMes4 , and DiICztBuCz4 possess similar ET but decreasing singlet–triplet energy gaps, ΔEST, enabling for the first time a comparison of the dependency of both the reaction kinetics and the final yield on this photophysical parameter. We observed that when the reaction kinetics are fast, there is little sensitivity to quenching of the excited PC by oxygen, implying that Dexter Energy Transfer (DET) to the substrate is competitive with DET to oxygen. Importantly, this means that some of the DET reactions using these PCs can be performed in air without adversely affecting reaction yield.Peer reviewe
Linguistic analysis and psychical research 1940-1960 : the case of Casimir Lewy
Get PDFThis paper explores a hitherto overlooked chapter in the history of analytic philosophy, namely the role that psychical research (i.e. the study of phenomena like telepathy, clairvoyance, ghosts, or communication with spirits of the dead) played in British philosophy between 1940 and 1960. This paper focuses on Casimir Lewy’s (1919–1991) engagement with psychical research and demonstrates that Lewy’s early work constitutes a move towards sustained application of the linguistic method to psychical research between 1940 and 1960. I argue that paying attention to psychical research during this period is significant for two reasons. The first is that this period represents a unique chapter in the history of the analytic tradition, namely, a philosophical preoccupation with the meaning of the language used by psychical researchers. The second is that a foundational moment in the history of analytic philosophy of religion is inseparable from its origin in psychical research.Peer reviewe
Non-Markovian effects in long-range polariton-mediated energy transfer
Get PDFFunding: K.B.A., B.W.L., and J.K. acknowledge support from EPSRC (Grant No. EP/T014032/1). P.F.W. acknowledges support from EPSRC (Grant No. EP/T518062/1).Intramolecular energy transfer driven by near-field effects plays an important role in applications ranging from biophysics and chemistry to nano-optics and quantum communications. Advances in strong light–matter coupling in molecular systems have opened new possibilities to control energy transfer. In particular, long-distance energy transfer between molecules has been reported as the result of their mutual coupling to cavity photon modes and the formation of hybrid polariton states. In addition to strong coupling to light, molecular systems also show strong interactions between electronic and vibrational modes. The latter can act as a reservoir for energy to facilitate off-resonant transitions and, therefore, energy relaxation between polaritonic states at different energies. However, the non-Markovian nature of these modes makes it challenging to accurately simulate these effects. Here, we capture them via process tensor matrix product operator methods to describe exactly the vibrational environment of the molecules combined with a mean-field treatment of the light–matter interaction. In particular, we study the emission dynamics of a system consisting of two spatially separated layers of different species of molecules coupled to a common photon mode and show that the strength of coupling to the vibrational bath plays a crucial role in governing the dynamics of the energy of the emitted light; at strong vibrational coupling, this dynamics shows strongly non-Markovian effects, eventually leading to polaron formation. Our results shed light on polaritonic long-range energy transfer and provide further understanding of the role of vibrational modes of relevance to the growing field of molecular polaritonics.Peer reviewe
Vocal consensus building for collective departures in wild western gorillas
Get PDFFunding: This work was supported by the University of Neuchatel, the Action Transversal of the National Museum of Natural History in Paris, the NCCR Evolving Language, Swiss National Science Foundation Agreement #51NF40_180888 and the ‘Origins syntax’, Swiss National Science Foundation Agreement #310030_185324.The ability to coordinate actions is of vital importance for group-living animals, particularly in relation to travel. Groups can only remain cohesive if members possess a cooperative mechanism to overcome differences in individual priorities and social power when coordinating departures. To better understand how hominids achieve spatio-temporally coordinated group movements, we investigated vocally initiated group departures in three habituated groups of western gorillas (Gorilla gorilla) in the Central African Republic. The large sexual dimorphism of gorillas has led to the untested assumption that the silverback males are the sole decision-makers in gorilla groups, although there are also observations that suggest otherwise. To address this, we analysed the direction and timing of group departures and found that high-ranking individuals (silverbacks and high-ranking females) were more successful in indicating the direction of future travel than others, but that the timing of departure was the apparent result of a cumulative vocal voting process among all adult group members. Our findings illustrate that even in species with a large sexual size dimorphism, travel decisions can be taken collectively via a consensus-building process.Peer reviewe
Comparing migration of Whinchats Saxicola rubetra from the non-breeding grounds in Liberia and Nigeria : differences due to geography but otherwise very similar
Get PDFFunding: Chris Goodwin, A.P. Leventis Conservation Foundation, AP Leventis Ornithological Research Institute, the British Ornithologists’ Union and the Linnean Society.Migrant birds in the Afro-Palearctic region are declining, so understanding general migration characteristics, such as site use, connectivity, and phenology is crucial for their conservation. We tracked 64 whinchats Saxicola rubetra, a declining Palearctic-breeding passerine, from non-breeding sites in Nigeria and Liberia, to Europe and back, in multiple years. We predicted differences, resulting from the geographical location of the two non-breeding sites, in location of respective breeding areas (migratory connectivity), number of non-breeding and stopover sites, migration distance and duration, degree of loop migration and phenology. But we predicted similarities, resulting from optimising migration behaviour, in migration leg distance duration, and stopover duration. Liberian tagged birds bred mainly in central and northern Europe, with Nigerian birds mainly in eastern Europe. Migratory spread was large resulting in range overlap and low connectivity. About 25% of whinchats used more than one sub-Saharan non-breeding site, their location dependent on geographic availability. Liberian birds had longer migrations in distance and duration, and more stopovers, but only Nigerian birds showed a statistically significant difference in longitude comparing spring and autumn migrations (i.e., a clear loop migration). Nigerian birds departed later than Liberian birds, independent of breeding latitude or migration distance, although latitude determined arrival time for breeding. Spring migration leg distance and stopover duration, and all leg durations, were similar for both populations; but Nigerian birds had longer duration stopovers and shorter distance migration legs in autumn. Whinchats were shown to have varied migration routes and characteristics, with a variable pace of migration that allows them between 50 and 75% of daylight hours to rest and forage, but with major stopover duration possibly being affected by site quality. One whinchat moved from sub-Saharan non-breeding site to northern European breeding site in 7 days, and 8% of complete migration durations were 14 days or less. This suggests whinchats are well adapted to the current variable geography and so may have the capacity to adapt to potential climate change across Europe and West Africa, although average quality and availability of stopover sites may be contributing to declines.Peer reviewe
Demographic biases in AI-generated simulated patient cohorts : a comparative analysis against census benchmarks
Get PDFBackground Generative artificial intelligence models are being introduced as low-cost tools for creating simulated patient cohorts in undergraduate medical education. Their educational value, however, depends on the extent to which the synthetic populations mirror real-world demographic diversity. We therefore assessed whether two commonly deployed large language models produce patient profiles that reflect the current age, sex, and ethnic composition of the UK. Methods GPT-3.5-turbo-0125 and GPT-4-mini-2024-07-18 were each prompted, without demographic steering, to generate 250 UK-based ‘patients’. Age was returned directly by the model; sex and ethnicity were inferred from given and family names using a validated census-derived classifier. Observed frequencies for each demographic variable were compared with England and Wales 2021 census expectations by chi-square goodness-of-fit tests. Results Both cohorts diverged significantly from census benchmarks (p < 0.0001 for every variable). Age distributions showed an absence of very young and older individuals, with certain middle-aged groups overrepresented (GPT-3.5: χ2(17) = 1310.4, p < 0.0001; GPT4mini: χ2(17) = 1866.1, p < 0.0001). Neither model produced patients younger than 25 years; GPT-3.5 generated no one older than 47 years and GPT-4-mini no one older than 56 years. Gender proportions also differed markedly, skewing heavily toward males (GPT-3.5: χ2(1) = 23.84, p < 0.0001; GPT4mini: χ2(1) = 191.7, p < 0.0001). Male patients constituted 64.7% and 92.8% of the two cohorts. Name diversity was limited: GPT-3.5 yielded 104 unique first–last-name combinations, whereas GPT-4-mini produced only nine. Ethnic profiles were similarly imbalanced, featuring overrepresentation of some groups and complete absence of others (χ2(10) = 42.19, p < 0.0001). Conclusions In their default state, the evaluated models create synthetic patient pools that exclude younger, older, female and most minority-ethnic representations. Such demographically narrow outputs threaten to normalise biased clinical expectations and may undermine efforts to prepare students for equitable practice. Baseline auditing of model behaviour is therefore essential, providing a benchmark against which prompt-engineering or data-curation strategies can be evaluated before generative systems are integrated into formal curricula.Peer reviewe
Evolution of terrestrial planetary bodies and implications for habitability
Get PDFFunding: We acknowledge support from Australian Research Council (ARC) Grant FL160100168, Leverhulme Trust Emeritus Fellowship EM-2025-067\4, Anusandhan National Research Foundation Start-Up Research Grant SRG/2023/001163, and DAE through NISER project RNI 4011.The terrestrial planetary bodies of our solar system—Mercury, Venus, Earth, and Mars—share a common origin through nebular accretion and early magma ocean differentiation, yet they diverged significantly in geological evolution, tectonic regimes, and habitability. Differences include distance from Sun, size, mechanism of internal cooling, degassing record, and resultant surficial conditions. Mercury, Mars, and Earth's Moon preserve largely mafic crust formed early in their evolution in a stagnant lid setting. Venus and Earth with their larger size record a long history of tectonic activity. Venus's mafic crust underwent large-scale resurfacing in the last billion years, likely in a stagnant lid setting but with potential areas of squishy lid behavior. The Earth preserves a long-lived plate tectonic regime in which young mafic crust beneath oceans is continually generated and recycled, whereas felsic crust forms emergent continents and spans much of the planet's history. The Earth is also characterized by a persistent magnetic field and a complex biosphere. Variations in tectonic modes between the terrestrial planets impact volatile exchange, magmatic outgassing, nutrient recycling and, in the case of Earth, provision of ecological niches. Other planets experienced transient habitability or remained uninhabitable, largely due to early cessation of tectonic and magnetic activity or atmospheric loss. Life may emerge under stagnant lid conditions, but sustained habitability and biological diversification require continued geological activity and crustal emergence. Insights from the terrestrial planets inform the search for habitable exoplanets, highlighting the intertwined roles of planetary interiors, surface processes, and atmosphere-crust interactions in shaping life-supporting environments.Peer reviewe
Magmatic and thermally produced reactive phosphorus 3.2 billion years ago and its implications for early life
Get PDFFunding: This work was financially supported by a Natural Environment Research Council (NERC- UKRI) Frontiers grant to EES (NE/V010824/1), a Marie Skłodowska-Curie Actions grant to ASB (EP/Y026497/1), and a German Research Foundation (DFG) grant (GE2558/4-1) to MMG. For XRD analyses, we also acknowledge the Engineering and Physical Science Research Council (EPSRC) Core Equipment Grant (EP/V034138/1).Reduced and polymerized phosphorus species may have been crucial for the origin and early evolution of life, as they are more reactive and soluble than phosphate. Thermal processes could have produced these phosphorus species; however, the underlying mechanism is poorly constrained, and geological evidence of polymerized species in the Precambrian is so far absent. Here, we investigated contact-metamorphic rocks from the ca. 3.22 Ga Moodies Group (South Africa), where mafic dikes intruded into shallow-marine sediments. We provide evidence of magmatic phosphite (up to 2.85 ppm) and metamorphic polyphosphate (up to 39.3 ppm). Additional laboratory experiments suggest that carbon can facilitate the thermal production of polyphosphates and reduced phosphorus species, including phosphide, from less reactive minerals such as apatite and vivianite. We conclude that magmatic and thermal-metamorphic rocks could have provided soluble and reactive phosphorus species crucial for the origin and early evolution of life.Peer reviewe
Diversity of Salmonella enterica isolates from urban river and sewage water in Blantyre, Malawi
Get PDFFunding: This work was primarily supported by the Bill and Melinda Gates Foundation through the Grand Challenges in Global Health initiative, awarded to Professor Nicholas Feasey (grant number INV-008749, https://www.grandchallenges.org/). This research was also supported in part by the Malawi-Liverpool-Wellcome Trust Programme, the institute where this study was conducted, which is funded under the Wellcome Asia and Africa Programme Grant 206545/Z/17/Z.Background Salmonella enterica encompasses over 2,600 serovars, including several commonly associated with severe infection in humans. Salmonella is a major cause of sepsis in Africa; however, diagnosis requires clinical microbiology facilities. Environmental surveillance has the potential to play a role in Salmonella surveillance. Methods We undertook water-based environmental surveillance in Blantyre, Malawi, from 2018-2020, taking samples from rivers (87.9%), a sewage plant (8.85%) and other water sources (3.24%), isolating and storing 1,042 non-typhoidal Salmonella (NTS) isolates in this period. Of these, 341 NTS isolates were whole genome sequenced, genome quality was checked, duplicate genomes from any given sample were removed and core genome phylogeny was reconstructed. AMRFinder, PathogenWatch and SISTR were used to further investigate serovar, sequence type and antimicrobial resistance determinants. Results After quality checks, and removal of duplicate genomes, 270 NTS genomes remained for further analysis. Multiple Salmonella serovars associated with human infection were detected, of which S. Typhimurium (55/270 isolates) was the most common, including 44 of Sequence Type (ST) 313, a serovar commonly associated with severe invasive disease (iNTS). Six lineage 2 ST313 genomes possessed AMR genes predicting multidrug resistance (MDR), while 29 lineage 3 isolates contained no AMR predictive genes. PCR based detection of staG has been proposed as a diagnostic marker of S. Typhi; however, all eight genomes that contained staG identified as Salmonella enterica serovar Orion, raising concerns about the specificity of this marker as a monoplex for environmental surveillance of S. Typhi. Discussion The study identified diverse Salmonella serovars in the environment, including those reported to cause invasive disease, emphasizing the complex but potentially valuable contribution of implementing environmental surveillance for Salmonella in high burden areas lacking diagnostic microbiology capacity.Peer reviewe
Revisiting history in the present : the politics of memories and emotions in regional negotiations among North Korea, Japan, and China
No full textThis dissertation investigates how memories and emotions intersect at the international level to influence security, diplomacy, and regional negotiations in Northeast Asia, focusing on North Korea’s relations with its two neighbours, Japan and China. Departing from existing studies that predominantly frame regional issues as traditional security concerns—centred on North Korea’s nuclear development and the responses of other states—this research examines how disputes on the Korean peninsula are also profoundly shaped by the interplay of emotion and historical memory, particularly those spanning from the Japanese annexation of Korea in 1910 through the post-Korean War period. At its core, the study explores the relational chain between memory and emotion: whether emotional resonance arises from the invocation of specific memories (memories-to-emotions), whether memories persist due to their emotional weight (emotions-to-memories), or a combination of both. This analysis argues that emotions act as sites of memory, functioning not only as reflections of historical narratives but also as repositories where memories are preserved, evoked, and reinterpreted. Through case studies on North Korea-Japan relations, North Korea-China relations, and the dynamics among these three neighbours in the Six-Party Talks, this dissertation contributes to the understanding of how emotions and memories interact to shape the political atmosphere and diplomatic negotiations in the region. By complementing traditional security paradigms with a memory-emotion lens, this research offers insights into state behaviour, while enriching ongoing discussions on international relations and negotiations surrounding security issues in Northeast Asia."I remain deeply indebted to the Linda and Gordon Bonnyman Charitable Trust, who funded
my PhD through the Douglas and Gordon Bonnyman Scholarship, and to the Great Britain
Sasakawa Foundation, who awarded me the Sasakawa Japanese Studies Postgraduate
Studentship."--Fundin
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