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Designing a climate change resilient landscape connectivity network from a multi-species perspective
Get PDFFunding: This research was funded by Natural England.There is strong evidence that climate change causes species range shifts and declines. Protected areas and suitable habitats are important for maintaining biodiversity. Species range changes depend on landscape connectivity between areas, facilitating movement and colonisation. Conservationists should identify landscape connectivity, as climate change causes species to move at different points in time. We quantified national connectivity for England for a sample of nationally important taxa associated with limestone and upland habitats, reflecting the White Peak as example focal region. We generated England-wide species distribution models for 15 species for three climate change time scenarios (Shared Socioeconomic Pathway 245): current, 2050 and 2090. We inverted these models, applying circuit theory analysis, to create connectivity maps. We applied -score standardisation to compare differences between scenarios. We considered the top decile of connectivity occurring across the time periods as the 'landscape connectivity network'. We compared this with the National Character Area framework of land parcels, the Site of Special Scientific Interest (SSSI) map, and quantified landcover in the network. The landscape connectivity network showed future species requirements becoming more diffuse, i.e., the landscape becoming more permeable. High connectivity value land lay in South West or South East England, and the central Pennines; implying range shifts to diverging latitudes. The network measured 1,029,000 ha, with 13% inside SSSIs. In the White Peak focal example, there were 7600 ha, with 38% inside SSSIs. Across England, the network's landcover included broadleaved woodland (365,000 ha), calcareous grassland (55,000 ha), and improved grassland (305,000 ha), the latter thought to be of low biodiversity value. This research innovates by combining connectivity assessments for widely different taxa associated with one habitat type for three climate change time scenarios. It shows how connectivity tends to be concentrated in certain areas of England, thereby identifying important national and regional connectivity areas to support species conservation planning.Peer reviewe
From forest to zoo : great ape behavior recognition with ChimpBehave
Get PDFFunding: The authors wish to express their appreciation to NCCR Evolving Language, Swiss National Science Foundation Agreement #51NF40_180888 and Grant No. CR31I3_166331 awarded to A.B. and K.Z. for their financial support in data collection and annotation.This paper addresses the significant challenge of recognizing behaviors in non-human primates, specifically focusing on chimpanzees. Automated behavior recognition is crucial for both conservation efforts and the advancement of behavioral research. However, it is often hindered by the labor-intensive process of manual video annotation. Despite the availability of large-scale animal behavior datasets, effectively applying machine learning models across varied environmental settings remains a critical challenge due to the variability in data collection contexts and the specificity of annotations. In this paper, we introduce ChimpBehave, a novel dataset comprising over 2 h and 20 min of video (approximately 215,000 frames) of zoo-housed chimpanzees, annotated with bounding boxes and fine-grained locomotive behavior labels. Uniquely, ChimpBehave aligns its behavior classes with those in PanAf, an existing dataset collected in distinct visual environments, enabling the study of cross-dataset generalization - where models are trained on one dataset and tested on another with differing data distributions. We benchmark ChimpBehave using state-of-the-art video-based and skeleton-based action recognition models, establishing performance baselines for both within-dataset and cross-dataset evaluations. Our results highlight the strengths and limitations of different model architectures, providing insights into the application of automated behavior recognition across diverse visual settings. The dataset, models, and code can be accessed at: https://github.com/MitchFuchs/ChimpBehavePeer reviewe
Bede's medical books
Get PDFThis paper re-examines the medical texts used by Bede in De temporum ratione and Retractatio in Actus apostolorum. It has long been accepted that he had access to works by Pseudo-Hippocrates, Vindicianus and Cassius Felix. Yet idiosyncrasies evident from his quotations complicate matters. Each highlights connections with distinctive textual traditions evident in early continental manuscripts and, especially in the case of the alleged influence of Vindicianus, other works. It shows the close affinities that Bede’s compendia had with Frankish medical miscellanies. In the process, we can also see something of how Bede dealt with a non-Christian body of knowledge, using it critically within his own intellectual projects.Peer reviewe
A study of a free convective boundary layer using a parcel-based Lagrangian model
Get PDFFunding: This research is funded by the UK Engineering and Physical Sciences Research Council (EPSRC, grant numbers EP/T025301/1 and EP/T025409/1) and the Natural Environment Research Council (grant NE/X018555/1). Samuel Wallace's PhD thesis was funded by the EPSRC (project reference: 1950021).We study the development of a dry convective boundary layer forced by surface heating and growing into a stably stratified atmosphere above. This is already a well-studied problem, and the novelty here is the application of a radically new, Lagrangian-based numerical approach. We employ the “Elliptical Parcel-In-Cell” (EPIC) method, which represents all prognostic quantities (e.g., vorticity and buoyancy) as a set of space-filling deformable ellipsoidal parcels. Mixing occurs via the splitting and merging of these parcels, which we view as turbulent mixing (it is localised in space, and is not like any existing eddy viscosity model). We compare our results with several recent comprehensive direct numerical simulation (DNS) studies and find broad agreement, and often close quantitative agreement, despite fundamental differences in the numerical methods employed. In particular, we reproduce the two-layer structure of the interface between the boundary layer and the free atmosphere.Peer reviewe
Surface plasmon-enhanced aptamer-based fluorescence detection of cocaine using hybrid nanostructure of cadmium-free ZnSe/In2S3 core/shell quantum dots and gold nanoparticles
Get PDFFunding: The authors gratefully acknowledge the financial support from Leverhulme Trust for funding this work. OA gratefully appreciates the support received from the School of Science and Engineering, University of Dundee.Cocaine abuse remains a global public health problem and a contributing factor to various social problems. In this work, we report on the development of a novel amphiphilic polymer (A-polym)-functionalized cadmium-free ZnSe/In2S3 core/shell quantum dots (QDs)-cationic cetyltrimethylammonium bromide (CTAB)-capped gold nanoparticle (AuNP) fluorescence nanoprobe for cocaine. ZnSe/In2S3 QDs were synthesized using the classic organometallic synthetic route for group II – VI semiconductor QDs and was surface-capped with organophosphorous-based ligands and organic-based stabilizers. A-polym, synthesized using an anhydride-capped polymer backbone and a nucleophilic agent, was used as a capping agent to coat and stabilize the QDs surface. The A-polym-coated QDs was electrostatically linked to cationic cetyltrimethylammonium bromide (CTAB)-capped gold nanoparticles (AuNPs) to form an A-polym-QDs-AuNP nanohybrid. The electrostatic interaction between the A-polym-coated QDs and CTAB-AuNPs quenched the fluorescence emission of the bound QDs. An MNS 4.1 anticocaine thiolated DNA aptamer (Aptm) was adsorbed on the A-polym-QDs-AuNP surface to form an Aptm-A-polym-QDs-AuNP nanoprobe. Upon interaction of cocaine with the Aptm-A-polym-QDs-AuNP nanoprobe, the fluorescence of the bound QDs was remarkably enhanced based on localized surface plasmon resonance-induced fluorescence emission signal. In general, the QDs functioned as the fluorophore reporter, CTAB-AuNP as a plasmon amplifier and the Aptm as the receptor. Under optimum reaction conditions, cocaine was selectively and quantitatively detected with a detection limit of 0.8 nM. Selectivity was achieved against other drugs and cocaine metabolites. The efficacy of the Aptm-A-polym-QDs-AuNP nanoprobe to detect cocaine in adulterated cocaine samples was successfully achieved.Peer reviewe
Twisted products of monoids
Get PDFFunding: This work was supported by the following grants: Future Fellowship FT190100632 of the Australian Research Council; EP/V032003/1, EP/S020616/1 and EP/V003224/1 of the Engineering and Physical Sciences Research Council. The first author thanks the Heilbronn Institute for partially funding his visit to St Andrews in 2025. The second author thanks the Sydney Mathematical Research Institute, the University of Sydney and Western Sydney University for partially funding his visit to Sydney in 2023.A twisting of a monoid S is a map Φ : S × S → ℕ satisfying the identity Φ(a, b) + Φ(ab, c) = Φ(a, bc) + Φ(b, c). Together with an additive commutative monoid M, and a fixed q ∈ M, this gives rise a so-called twisted product M ×qΦ S, which has underlying set M × S and multiplication (i, a)(j, b) = (i + j + Φ(a, b)q, ab). This construction has appeared in the special cases where M is ℕ or ℤ under addition, S is a diagram monoid (e.g. partition, Brauer or Temperley-Lieb), and Φ counts floating components in concatenated diagrams. In this paper we identify a special kind of ‘tight’ twisting, and give a thorough structural description of the resulting twisted products. This involves characterising Green’s relations, (von Neumann) regular elements, idempotents, biordered sets, maximal subgroups, Schützenberger groups, and more. We also consider a number of examples, including several apparently new ones, which take as their starting point certain generalisations of Sylvester’s rank inequality from linear algebra.Peer reviewe
Phase mixing of high and low frequency Alfvén waves in coronal loops
No full textThe phase mixing of Alfvén waves has long been considered a potential heating mechanism of the solar corona, and it has been postulated that the thermodynamic feedback of the heating may significantly affect the loop structure. It is unclear whether the dissipation of high frequency waves, which can be easily dissipated, or low frequency waves, which may accumulate energy in resonating coronal loops, may be a more efficient source of heating. We show that high frequency waves phase mix efficiently, heating the plasma and generating chromospheric upflows that increase the coronal mass. The continually dissipated wave energy maintains the new, hotter equilibrium against the increased energetic losses. The subsequent thermodynamic feedback associated with the heating leads to a deformation of the cross-field Alfvén speed profile, expanding the region where phase mixing can occur. The study was then extended to low frequency waves, which are shown to phase mix and dissipate inefficiently, resulting in minimal changes to the loop structure. We find little evidence of wave energy trapping inside the corona, even when the loop was modified to create more favourable conditions. Thus, we are unable to conclude that the dissipation of low-frequency Alfvén waves can be an effective heating mechanism in coronal loops, within the loop model presented. Finally, we study the effect of reducing or removing the artificial background heating profile and explore whether high frequency wave heating can partially sustain the loop profile without a background heating function. Wave heating within the shell region is shown to be able to fully offset a small decrease in the background heating profile. When the heating function was removed, a sharp density decrease occurred, and the system became a complex interplay between the increased amount of available energy, reduced energetic losses and decreased thermal capacity of the plasma."The research leading to the results presented within this thesis has received funding from the UK Science and Technology Facilities Council (Consol- idated Grant ST/V507076/1) and the Royal Society Wolfson Fellowship (RSWF/FT/180005). We acknowledge support from the University of St Andrews, the Research Council of Norway through its Centres of Excellence scheme, project number 262622 and the ASI/INAF agreement n. 2022-29HH.0."--Fundin
Spirobisindane-based hole transporting materials for conventional and indoor halide perovskite solar cells
Get PDFFunding: A-WS thanks Tertiary Education Trust Fund (TETFund) for funding. GC thanks the Leverhulme Trust for the award of a Research Fellowship and the EPSRC for grant (EP/E036244/1). LKJ acknowledges funding from UKRI-FLF through MR/T022094/1.Hole transporting materials (HTMs) are a vital component for both conventional and indoor perovskite solar cells. Spiro-OMeTAD has become one of the most widely studied HTM; however, its high molecular symmetry tends to give rise to nonuniform films that are not conducive to good photovoltaic device stability and large-area processing. Moreover, other issues relating to Spiro-OMeTAD, such as high cost, have spurred investigations into the development of new HTMs. Here, we report two spirobisindane-based HTMs ( AS-135 and AS-179 ) for conventional and indoor perovskite solar cells. The lower symmetry and ability to synthesize from cheap, readily accessible precursors provides obvious advantages over Spiro-OMeTAD. We show that spirobisindane-based HTMs are effective HTMs under both 1 Sun and indoor illumination upon doping with LiTFSi and power conversion efficiency ≈11% were demonstrated under 1 Sun and over 20% under 1000 lx indoor illuminance.Peer reviewe
Shifting patterns of mobility in the Insular Scandinavian diaspora between the ninth and eleventh centuries
Get PDFIn Insular history, the period from around 800 to 1300 was characterised by a series of increased interactions with Scandinavia, extending from the first recorded viking raids in the late ninth century down to the diplomatic relations between the kings of Norway, England and Scotland in the thirteenth and fourteenth centuries. This paper combines prosopographical and material approaches to explore the shifting patterns of mobility of members of the Scandinavian diaspora principally associated with Ireland and Britain across several centuries of this socially and materially entangled era. The principal portion of the paper is concerned with the mobility of three individuals: Óláfr of Hlaðir (ob.AD873×878), Óláfr Cúarán Sigtryggsson (ob.AD980×981), and Echmarcach Rǫgnvaldsson (ob.AD1064). A full, high-resolution discussion of the evidence for each individual is not possible within the confines of this article, but will be found in a series of pieces related to each figure currently either under review or in preparation.Peer reviewe
Quantifying hydrothermal ammonium mobilization from sediment and implications for the marine biosphere : a case study from the Guaymas Basin, Gulf of California
Get PDFFunding: This work was financially supported by a NERC Frontiers grant (NE/V010824/1) and a Leverhulme Trust grant (RPG-2022-313) to EES, as well as a UKRI fellowship (MR/W013835/1) to GM.Fluid-rock interactions in hydrothermal systems are capable of liberating ammonium (NH4+) from sedimentary organic material and making it bioavailable for benthic and pelagic microbial communities. Hydrothermal systems in organic-rich sedimentary basins are therefore thought to have played a key role in supplying bioavailable nitrogen to the early biosphere. To place new quantitative bounds on this process, we examined sediments from active hydrothermal systems in the Guaymas Basin, a young oceanic spreading center in the Gulf of California. We analysed four shallow sediment cores that were taken in the Guaymas Basin’s hydrothermally-active Southern Trough. We used a combination of isotopic tracers (δ15N, δ13C) and elemental abundances to explore nitrogen and metal mobility in buried sediments. We found that ca. 54% of the organically-bound nitrogen is remobilized by active seepage in the top 10 cm of the sediment package within as little as 27–83 yr. Extrapolating these findings over the hydrothermally-active area of the basin yields an ammonium seepage flux of ca. 1.3–4.1 mol/s. In addition, high temperature venting liberates ca. 156–187 mol/s, as estimated from previous data. Assuming biological uptake of hydrothermally recycled ammonium in the water column, these fluxes could support up to 1.3% and 58% of export productivity, respectively. Our data also reveal that the accumulation of micronutrients or potentially toxic metals is influenced by the presence of organic material in seep sediments. The Guaymas case study demonstrates that hydrothermal seepage in sedimentary basins can create a significant nutrient flux and is an efficient means of recycling nutrients from organic matter at shallow burial depths. Hydrothermal nutrient fluxes could therefore have enhanced microbial activity in Earth’s history, in particular during time intervals when Earth’s oceans are thought to have been nutrient-depleted. Our data also highlight the role of organic material in enhancing metal mobilization and accumulation in otherwise metal-starved hydrothermal seeps.Peer reviewe
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