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The genome sequence of Artibeus lituratus (Chiroptera, Phyllostomidae, Stenodermatinae; Olfers, 1818).
Full text linkFunding: This work was supported by UKRI Future Leaders Fellowship [MR/T021985/1 to SCV]; ERC Consolidator Grant [101001702; BATSPEAK to SCV]; Irish Research Council Laureate Award [IRCLA/2017/58 to ECT]; Science Foundation Ireland Future Frontiers [19/FFP/6790 to ECT]; Smithsonian National Museum of Natural History [Peter Buck Postdoctoral Fellowship to MRI]; Taxonomic Mammalogy Fund of the American Museum of Natural History to NBS; Smithsonian National Museum of Natural History to MRI.We present a genome assembly from an individual male Artibeus lituratus (Chordata; Mammalia; Chiroptera; Phyllostomidae). The genome sequence is 2.15 in span. The majority of the assembly is scaffolded into 30 chromosomal pseudomolecules, with the X and Y sex chromosomes assembled.Peer reviewe
Fictions of the Wikipedian fact : facticity, authority, and 21st-century fiction
Full text linkThis article considers the effect that Wikipedia has had on fiction of the 21st-century, and proposes that one distinctive feature of Wikipedia’s influence on this period has been the tension it has put on how novelists conceive of the relationship between facticity and authority. The first half of the article looks at how facticity and authority work on Wikipedia, drawing illustratively from Olga Tokarczuk’s Nobel Lecture (2019) and Ben Lerner’s short story ‘The Hofmann Wobble: Wikipedia and the Problem of Historical Memory’ (2023). The second half consists of a comparative reading of engagements with Wikipedia in Lucy Ellmann’s Ducks, Newburyport (2019) and Tokarczuk’s Bieguni (2007; trans. Flights 2017), in which I consider the two novels' contradictory responses to Wikipedia: Ducks as a turn towards the authority of the self, Flights as a valorisation of the self’s engagement with the other.Peer reviewe
Battle of the senses : evidence for competition and cooperation in multisensory perception
No full textPerceptual decisions often occur under uncertainty, where rapid and accurate responses are critical. While unisensory paradigms provide foundations, real-world perception is inherently multisensory. A central marker is the redundant signals effect (RSE): where responses are faster to multisensory stimuli than their unisensory components. The mechanisms driving the RSE remain debated, often framed as either cooperation (interaction) or competition (independence). This thesis advances understanding through behavioural experiments and computational modelling. First, using a novel dataset (N=21), I examined semantic congruency by equalising redundancy across conditions, a key innovation of this study. Congruent audiovisual signals produced larger multisensory speed-ups than incongruent ones, a modulation effect that cannot be explained by a competition account. Second, I investigate trial sequence effects in a new trimodal experiment (N=21). Here, the incorporation of tactile stimuli allowed all compared stimuli to be assessed following a full modality switch. Sequential dependencies shape multisensory response times, as predicted by a pure competition account, but do not modulate the magnitude of the RSE nor race model violations, challenging claims that violations may arise from sequence effects alone. Finally, using foundational archival data, I introduce the relay model, a novel two-stage account in which unisensory processes first compete in a race before initiating a second race from cross-modal interaction. This hybrid architecture captures key distributional properties of reaction times and offers a mechanistic explanation of how cooperation and competition jointly shape multisensory responses. Overall, the findings argue against purely cooperative or competitive models, instead supporting a hybrid view where multisensory decisions emerge from dynamic interplay between senses. Beyond clarifying RSE mechanisms, this work highlights the roles of congruency, sequential context, and multi-stage dynamics in perceptual decisions. More broadly, it demonstrates the value of computational modelling for linking behaviour to underlying mechanisms, with implications for understanding variability in multisensory perception
Holocene patterns of peat accumulation in Peruvian Amazonia
Full text linkFunding: The authors gratefully acknowledge the Anglo Peruvian Society, Charles University (PRIMUS/23/SCI/013), the Charles University Research Centre programme (UNCE/24/SCI/006), the Charles University/University of St Andrews Joint Seed Funding Scheme, the Johannes Amos Comeniuus (OP JAK) programme 'Natural and Anthropogenic Geohazards' (CZ.02.01.01/00/22_008_0004605), the Earth and Space Foundation, the Natural Environment Research Council (NERC: NE/R000751/1, NE/J50001X/1, NE/V018760/2), the Quaternary Research Association, and the Royal Geographical Society for funding.Peatlands accumulate and store carbon over centuries to tens of millennia. Analysing the age structure of peatlands helps us to understand their genesis, development, and stability as carbon stores, and informs peatland management. Here we analyse new and previously published radiocarbon dates from peatlands in the Pastaza-Marañón Basin in Peru, the largest known peatland complex in Amazonia. We show that peatlands here are younger (< c. 8900 and frequently <2500 years old) than in many other parts of the tropics. Basal peat ages in extant peatlands vary depending on the geomorphological stability of the landscape, with younger basal dates typically occurring close to active river floodplains and older basal dates in more stable contexts. The data indicate that within individual peatlands, peat initiation may occur synchronously across a basin, or peat may spread laterally from one or more nucleation sites. Only two out of seven well-dated records show clear hiatuses in past peat accumulation, suggesting that carbon sequestration in some, but not all peatlands has been vulnerable to landscape hydrological change or climate change. Peatland ecosystems in the region are economically important sources of non-timber forest products, which it may be possible to harvest sustainably without biomass loss or drainage, but our analysis indicates that the peat itself accumulates too slowly to be considered as a renewable resource on economically meaningful timescales.Peer reviewe
Pillared layered transition metal oxides for high-performance sodium-ion batteries
No full textSodium-ion batteries (SIBs) are emerging as cost-effective and sustainable alternatives to lithium-ion batteries (LIBs) for large-scale energy storage, owing to the abundance and low cost of sodium. Among the candidate cathodes, layered transition-metal oxides (NaₓTMO₂, 0.5 ≤ x ≤ 1.0, TM = transition metals) are especially attractive due to their high theoretical capacity, structural flexibility, wide voltage window, and favourable Na+ kinetics. However, their electrochemical performance is often limited by structural degradation in the Na-depleted state. To overcome this, recent studies highlight the use of Ca²⁺ or K⁺ substitution in the Na layer as structural pillars to improve cycling stability. This thesis systematically investigates the pillaring effect of Ca²⁺ and K⁺ on NaₓTMO₂.
Chapter 3 examines the role of Ni/Mn ratio in Ca-pillared O3-type MnFeNi-based oxides. For Ni-rich compositions - Na₁₋₂ₓCaₓNiₒ.₂₅Mnₒ.₂₅Feₒ.₅O₂ (x = 0.00, 0.03), Ca enhances cycling stability and reduces polarization but is less effective at suppressing Fe migration, while excessive Ca doping reduces rate capability. In Mn-rich compositions - Na₁₋₂ₓCaₓNiₒ.₁₇Mnₒ.₃₃Feₒ.₅O₂ (x = 0.00, 0.04), Ca pillaring provides stronger benefits, improving structural integrity, redox reversibility, and suppression of Fe migration.
Chapter 4 demonstrates a high-performance O3-Na₁₋₂ₓCaₓNiₒ.₃Feₒ.₄Mnₒ.₃O₂ (x = 0.03) material, delivering 128 mAh g⁻¹ initial capacity with 92% retention after 100 cycles. By using a combination of operando X-ray diffraction, and Mössbauer Spectroscopy, it is revealed that Ca incorporation broadens the solid-solution reaction, suppresses Fe migration, and mitigates structural distortion during cycling.
Chapter 5 compares Ca- and K-pillared materials within a unified host (P2-Naₒ.₇₆Mnₒ.₆Feₒ.₂₅Cuₒ.₁₅O₂), confirming enhanced structural reversibility relative to the unpillared sample. K-pillared materials show greater improvements in cycling stability due to expanded Na layer spacing and stronger TM–O interactions.
Chapter 6 explores 6% transition-metal vacancies in a P2-type MnCuFe-based oxide (Naₒ.₆₇Mnₒ.₅₈Feₒ.₁₉Cuₒ.₁₇[]ₒ.ₒ₆O₂), achieving 96.3 mAh g⁻¹ capacity with 103% retention after 200 cycles. Improved stability arises from progressive Mn redox activation, enhanced O redox reversibility, and suppression of the detrimental Z phase by vacancy introduction
Enabling abuse : the Imperial Japanese Army’s epidemic prevention and water purification organisation and its place in global military history
Full text linkThe most infamous of the Imperial Japanese Army’s Bōeki kyūsui-bu (BO), Unit 731, which conducted biological warfare and human experimentation, was able to commit these war crimes due to the BO’s organisational structures. As the ‘epidemic prevention and water purification’ organisations, the BO were tasked to support field forces in limiting disease spread and providing potable water. The combination of these tasks, along with an organic medical supply unit and a culture which gave authority and autonomy to medical officers, was unique in the world. However, when these BO organisations were employed at different echelons throughout the Japanese Empire, nearly all failed to accomplish their mission in a field setting. The ‘successful’ BO organisations were those that exploited the system and conducted human experimentation war crimes.
Grounded in centuries of military history, Japan’s development of its national standing army coincided with a larger global trend of specialisation and professionalisation, in both the military and medical fields. Using Germany as its model, Japan was able to quickly develop a capable military in a short time. Victory in the Russo-Japanese War and the acclaim from around the world, led Japan to keep its army structures as they existed at the end of the war where they were never meaningfully critiqued or analysed for potential organisational weaknesses. As Japan moved into World War Two, the unique environment created by the authority and autonomy of conscripted medical professionals with easy access to medical supplies, led some BO organisations to commit human experimentation crimes. Ultimately, Japan’s lack of oversight, either military or civilian, allowed medical officers free reign to conduct whatever research they believed was in the military or the nation’s best interest, resulting in the human experimentation war crimes of Unit 731."This work was supported by the Sasakawa Foundation (2022-2025); the Albert Baker Fund (2022-2024); the Jonathan and Hazel Sparey Scholarship (2023-2025); the St. Andrews Society of D.C. (2022); and the United States Post-9/11 GI Bill (2023-2024)."--Fundin
Global perspectives on telemedicine-enabled medication for opioid use disorder : practices, priorities, and barriers
Full text linkIntroduction: Telemedicine (TM) has potential to address the global opioid use disorder treatment gap, yet its uptake, priorities, and barriers have not been mapped internationally. Methods: We conducted a cross-sectional, web-based survey (July to November 2024) of clinicians and clinical leaders via the International Society of Addiction Medicine, World Psychiatric Association, and allied contacts. The questionnaire captured telemedicine facilitated medication for opioid use disorder (TMOUD) practices, priorities, and barriers. Responses were summarised overall and stratified by World Bank country-income group and by current TMOUD availability. Results: Sixty-eight experts from 37 countries, 32% from low/middle-income countries (LMICs), participated. General TM use rose from 57% before COVID-19 to 94% in 2024. TMOUD was available in 26 jurisdictions (38%), more often in high-income than LMIC settings (58% vs 11%). Barriers to prescribing were identified, and few settings reimbursed video and telephone consultations equally. Improving treatment retention (69%), reducing missed appointments (62%), and expanding medications to underserved (60%) or remote (57%) populations as top priorities, yet fewer than 40% reported that TMOUD was currently used to meet those goals. Key barriers were inadequate policy support (60%), lack of professional guidance (63%), restrictive regulation (48%), poor digital infrastructure (broadband 29%; e-prescribing 56%), and limited clinician training (54%); almost every barrier was more common in LMICs. Discussion: TMOUD remains uneven and concentrated in high-income countries. Updated clinical guidance, digital connectivity investment and interoperable e-health systems, and targeted workforce development, particularly in LMICs, are needed to realise TM's potential for equitable and effective treatment of opioid use disorder. This global survey fills a critical knowledge gap by documenting expert perspectives across income settings, offering cross-national evidence to inform equitable expansion of TMOUD worldwide.Peer reviewe
Scale-dependent foraging behaviour and habitat associations of two sympatric marine top predators
Full text linkFunding: NERC (NE/T010614/1, NE/Y006194/1); Department for Energy Security and Net Zero; NERC (NE/R015007/1)Context: Theoretical research has considered how animals should optimise foraging strategies to maximise fitness, adapting search scale to exploit different habitats and minimise competition. Empirical studies have described multi-scale area-restricted search (ARS) strategies for some species, but the physical and biological mechanisms underpinning such behaviour are rarely studied. Objectives: Our objectives were to quantify the presence, prevalence, and habitat associations of scale-dependent foraging for two sympatric seal species, accounting for regional variation across the seascape. Methods: We analyse a GPS telemetry dataset of 116 grey (Halichoerus grypus) and 325 harbour seals (Phoca vitulina) tracked throughout the North Sea. We test the existence of multi-scale ARS, comparing hidden Markov models (HMMs) with two ARS states against more conventional HMMs (one ARS state). We quantify regional variation and examine the scale-dependence of foraging habitat associations using post-hoc “use-encounter” models. Results: Both species exhibited nested broad-scale and focussed ARS. Accounting for scale resulted in increases of up to 25% and 46% in inferred ARS for grey and harbour seals respectively. The prevalence and habitat associations of different ARS scales varied in a regional species-specific manner. Conclusions: We demonstrate the first application of HMMs to capture multi-scale ARS from animal-borne tracking data. Overlooking scale-dependence may mask individual variation and underestimate ARS, with consequences for ecological understanding and conservation applications. We hypothesise that seals employ different search scales for different habitats, competition levels and/or prey types. We call for further research to elucidate the prevalence and ecological significance of this phenomenon in other aquatic predators.Peer reviewe
Problematic usage of the internet : converging and diverging terminologies and constructs
Full text linkProblematic usage of the internet (PUI) is an increasing global concern, leading to significant negative impacts in various levels. PUI is an umbrella term comprised of subcategories, including online gaming disorder, online gambling disorder, online buying-shopping disorder, online compulsive sexual behavior disorder, problematic usage of social media, cyberchondria, cyberbullying, and digital hoarding. With respect to the diversity of these categories, a factor that further impedes the field of PUI is not recognizing these subcategories under the PUI. To estimate the state of the field, we conducted a systematic review on a sample time frame, 2022–2023, and we found that among 2,497 relevant papers, only 13% of the studies on PUI subcategories used PUI as an umbrella term. Establishing PUI as an overarching terminology, as we do with substance use disorder (SUD) as a term while respecting the diversities within its subcategories, would synergize research efforts, facilitate comparisons, and inform treatment strategies. As technology continues to evolve, terminological refinement is critical to maintaining relevance and accessibility for researchers and the broader community.Peer reviewe
Boron isotope evidence for high-latitude ocean control of glacial CO₂
No full textHigh-latitude oceans are crucial components of the global carbon cycle, acting as primary drivers for atmospheric CO₂ changes over glacial cycles due to their connection to the deep ocean and unique biogeochemistry. However, the key processes responsible for glacial CO₂ change in the high-latitude oceans remain poorly constrained, due to lack of surface water CO₂ reconstructions. This thesis addresses this gap by advancing the analysis and application of the boron isotope (δ¹¹B)-pH proxy.
Chapter 2 presents a novel pumped chromatography technique to purify boron from carbonate and seawater matrices, called “peri-columns”, which operates eight-fold faster than the gravity column methods, while achieving significantly lower total procedural blanks (~11 pg boron).
Chapter 3 presents an 800-kyr-long Southern Ocean reconstruction and shows that major pCO₂ decline in the Antarctic Zone (AZ) at glacial inception was pivotal in driving the initial atmospheric CO₂ drawdown. This was mechanistically linked to shifts in ocean circulation—likely driven by changes in sea ice and the westerly winds—which reduced surface carbon supply and suppressed CO₂ outgassing.
Chapter 4 presents the first paired δ¹¹B and Mg/Ca records for the subpolar North Pacific (SNP) spanning the past 150 ka, which highlight its carbon cycle dynamics under different boundary conditions. Deglacial surface SNP pCO₂ change during Termination II was driven by sequential changes in deep convection and wind-driven upwelling. Enhanced Pacific Meridional Overturning Circulation reduced glacial CO₂ and warmed surface waters during Marine Isotope Stage (MIS 4), with subsequent weakening leading to CO₂ rise during early MIS 3.
Chapter 5 details the first evaluation of δ¹¹B analysis using the Sapphire collision-cell multi-collector inductively coupled plasma mass spectrometer, identifying optimal instrumental configurations that yield precision comparable to other established techniques."This work was supported by the Natural Environment Research Council-IAPETUS2 Doctoral Training Programme [grant number NE/S007431/1]. The sample analyses were also supported by the European Research Council Starting Grant “Old CO2 New Archives” awarded to James Rae [grant agreement 805246]."--Fundin
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