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Recent Submissions

Simple, rapid, scalable confined synthesis of ultrafine Pt nanoclusters for fuel cells
(Elsevier B.V., 2026) Chidziva, Stanford; Bai, Yiming; Sang, Chengcheng
Small-sized nanoclusters exhibit catalytic activity in electrochemical reactions distinct from the bulk-like properties of nanoparticles 2 nm or larger, yet their surfactant-free synthesis remains a formidable challenge. A scalable microchannel-confined synthesis method enables rapid, controlled formation of 1.12 nm Pt nanoclusters without additional surfactants. Kinetic control achieves a nucleation and growth time of approximately 18.6 s, with heat transfer simulations confirming uniform temperature attainment within 0.5 s. Half-cell and single-cell tests, corroborated by density functional theory (DFT) calculations, demonstrate exceptional performance of these Pt nanoclusters in proton exchange membrane fuel cell (PEMFC), achieving a mass activity 1.9 times that of commercial samples and a rated power density of 1.55 W cm−2. This method can employ multiple capillaries assembled into a capillary bundle to enable parallel experiments, highlighting its scalability and potential to advance hydrogen-electricity conversion technologies.
Evaluation of risks of oil contamination in endangered seabirds in Algoa Bay, South Africa, linked to ship-to-ship bunkering and anthropogenic maritime activities
(Elsevier Ltd, 2026) Ludynia, Katrin; Stassen, Monica; Fearon, Giles
This study evaluates the ecological risks of oil contamination to endangered seabirds in Algoa Bay, South Africa, linked to ship-to-ship (STS) bunkering activities and other anthropogenic maritime activities. Between 2016 and 2024, 378 oiled seabirds—primarily African penguins and Cape gannets—were admitted to rehabilitation centres, with over half linked to STS-related spills. An established modelling system was used to model the trajectory of oil from the MV Chrysanthi S spill in 2019 (400 L of Heavy Fuel Oil), using the simulated environmental conditions at the time of the spill. The model predicted that core foraging areas would have remained exposed to oil for about a week after the spill and that birds would have been found and rescued days after their contamination. Probabilistic modelling of 200 spill scenarios revealed high likelihoods of shoreline oiling and persistent surface contamination, especially during austral winter, when oil is more likely to reach Bird Island's seabird foraging areas. Spills from the offshore extent of anchorage area 2 are more likely to result in impacts on the seabird foraging areas. The model indicates that a high degree of conservatism is required when selecting ecological thresholds for impacts on African penguins, given the relatively high observed impacts despite low modelled surface thicknesses from a 400 L spill. These findings underscore the urgent need for stricter regulation of offshore bunkering in ecologically sensitive areas and improved preparedness for wildlife rescue and rehabilitation, especially in an area of such high biodiversity as Algoa Bay.
Source area reconstruction using heavy mineral, mineral chemical, geochronological and palaeocurrent data: carboniferous sandstones of the Scottish midland valley
(Elsevier B.V., 2026) Frei, Dirk; Morton, Andrew Clifford; Chisholm, Ian
Integration of several data sets (heavy mineral analysis, rutile and apatite trace element geochemistry, zircon, rutile and apatite geochronology, and palaeocurrent measurements), in conjunction with published sedimentological and petrographic data, has enabled a reconstruction of source areas supplying Late Devonian and Carboniferous sandstones in the eastern part of the Scottish Midland Valley. There is evidence for both first-cycle and recycled detrital sources, and for temporal variations in sediment supply patterns. These temporal shifts in provenance have enabled the succession to be divided into six units of different character (Packages 1 to 6). Late Devonian sandstones (Package 1) have comparable characteristics to Lower Palaeozoic sandstones of the Scottish Southern Uplands Block to the south, and are interpreted as recycled from similar material. Differences in apatite morphology testify to a shift from aeolian deposition in the Knox Pulpit Formation to fluvial deposition in the overlying Kinnesswood Formation. A recycled source is also inferred for the overlying Strathclyde Group (Visean) sandstones (Package 2), on the basis of depletion of weatherable mineral components, but palaeocurrent evidence and mineral chemical data indicate a change in source area location and sediment input direction. Recycling from an Upper Old Red Sandstone source (Late Devonian) in the Moray Firth to the north is considered most likely. Input from a more distant northern source, delivered by the ‘Pennine River' appears in the later part of Package 2, and becomes dominant at the base of the Limestone Coal Formation (Namurian) (Package 3). The Pennine River was a large fluvial system that is known to have supplied much of the Carboniferous succession in the Pennine Basin of Yorkshire and Northumberland. The new rutile trace element and geochronological data acquired in this study confirm that the source region included parts of East Greenland where high-grade (granulite facies) metapelites formed during the Caledonian orogenic cycle are located.
Populating Galaxies into haloes via machine learning on the simba simulation
(Oxford University Press, 2026) Davé, Romeel; Das, Pratyush Kumar; Cui, Weiguang
We present a machine learning (ML) based framework, machine inferred galaxy (MIG), designed to populate dark matter haloes with galaxies in N-body simulations. MIG predicts galaxy stellar mass ($M_*$), star formation rate (SFR), atomic and molecular gas masses (Hi mass ($M_{\rm H\,{\small I}}$), and H$_2$ mass ($M_{\rm H2}$)), and metallicity, and can be readily extended to other galaxy properties and simulations. The framework first separates haloes into central and satellite systems, then uses ML classifiers to distinguish star-forming (SF) from quenched (Q) galaxies, followed by separate regressors trained on the SF subgroups for both centrals and satellites. MIG is trained on the $(100\, h^{-1}\mathrm{Mpc})^3$ Simba galaxy formation simulation at $z=0$ and achieves high accuracy for key baryonic properties, including a regression score close to 0.9 for $M_{\rm H\,{\small I}}$ predictions of central galaxies. We further demonstrate its robustness at $z=1$ and $z=2$. Training on fractional quantities (e.g. $M_{\rm H\,{\small I}}/M_*$) and then rescaling by the predicted $M_*$ yields improved performance over direct predictions across all properties and redshifts. MIG also reproduces galaxy mass distribution functions with higher fidelity, an essential step for accurately predicting integrated quantities such as Hi intensity maps. These results establish MIG as an efficient and physically consistent tool for generating mock galaxy catalogues and baryonic tracers in large cosmological volumes for various surveys.
Assessing patterns of authorship of low- and middle-income countries in global commercial clinical trials in oncology
(BioMed Central Ltd, 2026) Ravinetto, Raffaella; Payedimarri, Anil Babu; Mouhssine, Samir
Poor authorship practices in global health research may be a sign of unequal partnerships. Previous studies have shown that authors from low- and middle-income countries (LMICs) are frequently underrepresented in publications from global research collaborations between LMICs and high-income countries (HICs). To the best of our knowledge, the patterns of authorship from LMICs in international industry-sponsored clinical research on breast, lung and colon cancer have not yet been investigated. Therefore, as a spin-off to broader research on globalization of commercial clinical trials in oncology, we conducted an analysis of authorship in the publications from completed industry-sponsored therapeutic trials in breast, lung and colon cancer (from phase I to IV) that involved LMICs. Only articles published in a peer-reviewed journal in English by March 30, 2024 were included. A total of 302 publications from 173 trials were analysed. 63% (n = 191) of them have at least one author from a middle-income country (MIC); 14% (n = 42) articles have the first author from a MIC; and 13% (n = 39) articles have the last author from a MIC. Conversely, 37% (n = 111) of articles had no author from MIC, including two trials conducted only in MICs. In conclusion, our study found an imbalance in authorship, suggestive of significant inequalities, in collaborative research in industry-sponsored clinical trials for breast, lung and colon cancer. Industry sponsors need to work towards greater equity in authorship when collaborating with researchers in (L)MICs, and oncology researchers and opinion leaders in HICs should actively advocate for greater fairness to their colleagues in (L)MICs.