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Tabular Data for experimental measurements and numerical simulations describing spiking patterns in a three-neuron circuit composed of diffusive memristors
No full textThe stochastic dynamics of a three-neuron circuit composed of diffusive memristors is investigated. This circuit simulates synaptic convergence where two primary neurons synapse onto a single secondary neuron. Experimental measurements and numerical simulations are performed to study how applying input voltages V1 and V2 onto the primary neurons 1 and 2 respectively influence spiking behavior in the neuromorphic circuit. We reveal input voltage combinations leading to different spiking patterns (i.e. spiking of one, two or three memristors) depending on resistances and noise applied. These findings enable the design of large-scale reconfigurable neuromorphic circuits which combine the responses of functional neuromorphic blocks.fig6a: experimental file shows the experimental measurements of spiking patterns observed for load resistors RL = 55 kΩ and 60 kΩ applied to artificial primary neurons 1 and 2 respectively with input voltages V1,2 ϵ [0,3.6] and voltage step 0.2V.fig6b: theory file shows spiking patterns observed for parameters 2kBη1 = 10−4, 2kBη2 = 10−3 and 2kBη3 = 2.9×10−4 with V1,2 ϵ [0,400] (voltage step 20V) and randomized potential using derived governing equations that characterize the neuromorphic circuit's spiking dynamics.Qualitative spiking behavior observed in numerical simulations match experimental measurements.© the authors</p
Evaluating the cooling thermal response of UK dwellings
No full textCombatting climate change and energy shortages requires optimising the energy system. The global energy system is transitioning towards net-zero greenhouse gas emissions by 2050 through decarbonisation and electrification. Buildings, which consume 30 to 40% of total energy, play an important role in this transition. It is necessary to move from fossil-fuel heating to electrified systems such as heat pumps and to establish robust methods to assess building thermal dynamics and flexibility. Evaluating building flexibility helps reduce peak electricity demand and improve building energy management, thereby supporting the decarbonisation strategy. This thesis addresses the need for building energy flexibility by developing two metrics to evaluate the cooling thermal response of occupied UK dwellings during heating-off periods. Using measured performance data, the methodology introduces two metrics: the cooling time constant, which quantifies the rate of indoor temperature decay, and the fractional temperature drop, which expresses the proportion of the actual temperature drop relative to the maximum temperature drop potential. The approach was applied to two empirical datasets of UK dwellings, representing both detailed individual dwellings and typical semi-detached dwellings in the UK. Results showed that cooling time constants generally ranged from 20 to 60 hours, highlighting significant variation in thermal inertia across dwellings. A strong negative correlation was observed between the two metrics: dwellings with higher cooling time constants exhibited lower fractional temperature drops. These findings confirm the fractional temperature drop as a practical alternative metric to the cooling time constant. By providing a data-driven method to assess cooling thermal response, this research contributes to demand-side energy management strategies, such as demand response programmes, and supports future low-carbon building design.</p
Amorphous/crystalline interwoven multipods with high Co/Ni activity for wide-temperature-range sodium-sulfur batteries
No full textSluggish kinetics caused by 16-electron transfer hinders development of wide-temperature-range sodium-sulfur batteries. Here we report Sn-doped CoNiS multipods with an amorphous-crystalline interwoven structure. Employed as a positive electrode catalyst, the resulting sodium–sulfur battery exhibits a discharge capacity of 1320.8 mAh g −1 at 3 A g −1 after 1200 cycles at room temperature, together with stable and high-capacity electrochemical performance ranged from −20 to 50 °C. It has been evidenced that the amorphous/crystalline interfaces generated by Sn doping can adjust the microelectronic environment of Co and Ni atoms, optimize their adsorption energy toward sodium polysulfide intermediates through Co–S and Ni–S bonding, and thus decrease the energy barrier of polysulfide conversion. This interfacial regulation efficiently lowers the energy barrier of the rate-determining step and facilitates the overall reaction kinetics over a wide temperature range. This work provides an efficient amorphous/crystalline interface engineering strategy to develop high-performance catalysts.</p
Mapping the flow of painterly gesture
No full textImpressionist paintings are noted for their luminous, texturally rich surfaces, and bold brushwork plays a central role in shaping their visual impact and meaning. Although styles differed between painters, Impressionist artists typically privileged immediacy over finish, allowing a wide variety of gestures to remain a visible and assertive presence in the final work. Despite its significance, the directional organization of brushstrokes remains difficult to isolate or analyze systematically in individual paintings. Here, we investigate whether streamlines, derived from local gradients and directional cues embedded in the painted surface, can offer a computational ‘‘mapping’’ of painterly gesture through the manifestation of brushstroke directionality.</p
Supplementary information files for "High-performance modelling of urban non-point-source pollutant dynamics: a full-process approach"
No full textSupplementary files for article "High-performance modelling of urban non-point-source pollutant dynamics: a full-process approach"Non-point-source pollutants (NPSPs) are a major cause of urban water quality degradation. Effective management requires an understanding of pollutant dynamics across spatial scales. Existing storm water quality models are often based on empirical or hydrological approaches, which have limited capacity to represent flow-pollutant interactions and particle-facilitated dynamics in complex urban environments. Physically based models provide a more realistic description, but their applications are constrained by high computational costs and detailed data requirements. This study presents a high-performance, GPU-accelerated hydrodynamic-particle-based water quality model to simulate the full dynamics of wash-off, deposition, and transport of urban particulate-based NPSPs at high spatial resolution. The initial pollutant mass and particle size distribution (PSD) fields were derived from a physics-informed Random Forest build-up model trained on literature-reported data. The model was validated using two monitored events in a road catchment near Paris, achieving NSEs of 0.86 for runoff and 0.67 for pollutant fluxes. Sensitivity analyses revealed a strong dependence on the single particle mass (Pm), with simulation accuracy becoming stabilised beyond 50 particles per grid. Application to a real-world urban case study confirmed the framework's efficacy in reproducing flood inundation and NPSP propagation. The analysis further underscores that a resolution finer than 5 m is necessary for reliable simulations in complex urban settings. The particle-tracking capability enabled spatio-temporal pollutant source identification. This framework presents a valuable tool for scientists, policymakers, and environmental practitioners to advance urban water quality management.© The Author(s), CC BY 4.0</p
Harmonic locus and Calogero-Moser spaces
No full textWe study the harmonic locus consisting of the monodromy-free Schrödinger operators with rational potential and quadratic growth at infinity. It is known after Oblomkov that it can be identified with the set of all partitions via the Wronskian map for Hermite polynomials. We show that the harmonic locus can also be identified with the subset of Wilson’s Calogero–Moser space that is fixed by the symplectic action of C×. As a corollary, for the multiplicity-free part of the locus we effectively solve the inverse problem for the Wronskian map by describing the partition in terms of the spectrum of the corresponding Moser matrix. We also compute the characters of the C×-action at the fixed points, proving, in particular, a conjecture of Conti and Masoero. In the Appendix written by N. Nekrasov there is an alternative proof of this result, based on the space of instantons and the ADHM construction.</p
Parent reports of eating behaviour and feeding practices: effects of parent and child sex
No full textResearch on parental feeding practices has focused on mothers, often overlooking fathers' perspectives and the influence of child sex. This study examined (1) differences between fathers' and mothers' own eating behaviours, their use of feeding practices, and perceptions of their children's eating behaviours, and (2) the role of child sex in these perceptions and practices. Parents (N = 784; 145 fathers and 639 mothers) of preschoolers (3–5 years, 51.3 % female) from the UK completed an online survey assessing their eating behaviours and feeding practices, and their child's eating behaviours. There were significant sex differences in parents' eating behaviours, with mothers reporting more emotional overeating, hunger, satiety responsiveness, and slowness in eating. Mothers and fathers did not differ in their reports of children's eating behaviours. Girls were reported to have higher levels of satiety responsiveness than boys. When exploring the interaction of parent and child sex in reports of eating behaviour, fathers reported that girls had more desire to drink. Mothers and fathers differed in their reported use of some feeding practices. Both mothers and fathers reported greater use of food for emotion regulation with girls than boys. Fathers used more encouragement of balance and variety with boys. These findings highlight distinct patterns in feeding practices and eating behaviours, influenced by both parent and child sex, suggesting that girls may be at greater risk of receiving feeding practices that contribute to the development of emotional eating. These results emphasize the need to consider the role of sex in future research and the development of tailored feeding guidance.</p
Fresh produce seller in Mandela Village, Hammanskraal, Pretoria, Gauteng, South Africa
No full textA man selling fresh produce walks past a house in Mandela Village. The man is selling vegetables on a homemade wheelbarrow. The man is wearing pink, blue, brown, and green clothes. In the background is a cement house with red and grey roof tiles and a wire fence.</p
Man painting in Mandela Village, Hammanskraal, Pretoria, Gauteng, South Africa
No full textA man stands on a broken white chair, painting a brown-coloured window frame. On the ground are a white bucket and a brown two-litre bottle. The man wears a white hat, grey shirt, yellow pants, and black shoes. White curtains are visible inside the house. The background for the photograph is the light brown wall of the house. On the right side of the picture is a door with a red plastic bag lying on the ground.</p
Cars in motion in Tsamaya Avenue, Mamelodi, Pretoria, Gauteng, South Africa
No full textMultiple cars are in motion on Tsamaya Avenue in Mamelodi. People on the sidewalk are looking at the cars. Red and white stop signs are at the left of the picture, and green hills are in the image's background.</p