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Recent advances in nanomaterials have pushed the boundaries of nanoscale fabrication to the limit of single atoms (SAs), particularly in heterogeneous catalysis. Single atom catalysts (SACs), comprising minute amounts of transition metals dispersed on inert substrates, have emerged as prominent materials in this domain. However, overcoming the tendency of these SAs to cluster beyond cryogenic temperatures and precisely arranging them on surfaces pose significant challenges. Employing organic templates for orchestrating and modulating the activity of single atoms holds promise. Here, we introduce a novel single atom platform (SAP) wherein atoms are firmly anchored to specific coordination sites distributed along carbon-based polymers, synthesized via on-surface synthesis (OSS). These SAPs exhibit atomiclevel structural precision and stability, even at elevated temperatures. The asymmetry in the electronic states at the active sites anticipates the enhanced reactivity of these precisely defined reactive centers. Upon exposure to CO and CO2 gases at low temperatures, the SAP demonstrates excellent trapping capabilities. Fine-tuning the structure and properties of the coordination sites offers unparalleled flexibility in tailoring functionalities, thus opening avenues for previously untapped potential in catalytic applications., Comment: Main text (12 pages, 4 figures) and supplementary information (15 pages, 16 figures)

Memristors stand out as promising components in the landscape of memory and computing. Memristors are generally defined by a conductance equation containing a state variable that imparts a memory effect. The current-voltage cycling causes transitions of the conductance, determined by different physical mechanisms such as the formation of conducting filaments in an insulating surrounding. Here we provide a unified description of the set and reset processes, by means of a single voltage activated relaxation time of the memory variable. This approach is based on the Hodgkin-Huxley model that is widely used to describe action potentials dynamics in neurons. We focus on halide perovskite memristors and their intersection with neuroscience-inspired computing. We show that the modelling approach adeptly replicates the experimental traits of both volatile and nonvolatile memristors. Its versatility extends across various device materials and configurations, capturing nuanced behaviors such as scan rate- and upper vertex-dependence. The model also describes well the response to sequences of voltage pulses that cause synaptic potentiation effects. This model serves as a potent tool for comprehending and probing the underlying mechanisms of memristors, by indicating the relaxation properties that control observable response, which opens the way for a detailed physical interpretation.

We compute masses of twenty positive parity first radial excitations of spin-$1/2$ and $3/2$ baryons composed of u,d,s,c and b quarks in a quark-diquark picture within a contact interaction model. These excitations comprise of two elements: one characterized by a zero in the Faddeev amplitude, representing a radial excitation of the quark-diquark system and the other marked by a zero in the diquark's Bethe-Salpeter amplitude, corresponding to an intrinsic excitation of the diquark correlation. Wherever possible, we compare our results with other models and/or experiment. We verify that the masses obtained through our model conform to the spacing rules for all the baryons studied, whether light or heavy and whether of spin 1/2 or 3/2. The computed masses do not just offer a guide to the future experimental searches but also compare well with the existing candidates for the possible radial excitations of some heavy baryons., Comment: 17 pages, 9 figures and 11 tables

The standard Poisson-Boltzmann model for molecular electrostatics assumes a sharp variation of the permittivity and salt concentration along the solute-solvent interface. The discontinuous field parameters are not only difficult numerically, but also are not a realistic physical picture, as it forces the dielectric constant and ionic strength of bulk in the near-solute region. An alternative to alleviate some of these issues is to represent the molecular surface as a diffuse interface, however, this also presents challenges. In this work we analysed the impact of the shape of the interfacial variation of the field parameters in solvation and binding energy. However we used a hyperbolic tangent function ($\tanh(k_p x)$) to couple the internal and external regions, our analysis is valid for other definitions. Our methodology was based on a coupled finite element (FEM) and boundary element (BEM) scheme that allowed us to have a special treatment of the permittivity and ionic strength in a bounded FEM region near the interface, while maintaining BEM elsewhere. Our results suggest that the shape of the function (represented by $k_p$) has a large impact on solvation and binding energy. We saw that high values of $k_p$ induce a high gradient on the interface, to the limit of recovering the sharp jump when $k_p\to\infty$, presenting a numerical challenge where careful meshing is key. Using the FreeSolv database to compare with molecular dynamics, our calculations indicate that an optimal value of $k_p$ for solvation energies was around 3. However, more challenging binding free energy tests make this conclusion more difficult, as binding showed to be very sensitive to small variations of $k_p$. In that case, optimal values of $k_p$ ranged from 2 to 20.

In the quest to harness the power of quantum computing, training quantum neural networks (QNNs) presents a formidable challenge. This study introduces an innovative approach, integrating the Bees Optimization Algorithm (BOA) to overcome one of the most significant hurdles -- barren plateaus. Our experiments across varying qubit counts and circuit depths demonstrate the BOA's superior performance compared to the Adam algorithm. Notably, BOA achieves faster convergence, higher accuracy, and greater computational efficiency. This study confirms BOA's potential in enhancing the applicability of QNNs in complex quantum computations., Comment: 5 pages 2 figures

Hot and warm Jupiters might have undergone the same formation and evolution path, but the two populations exhibit different distributions of orbital parameters, challenging our understanding on their actual origin. The present work, which is the results of our warm Jupiters survey carried out with the CHIRON spectrograph within the KESPRINT collaboration, aims to address this challenge by studying two planets that could help bridge the gap between the two populations. We report the confirmation and mass determination of a hot Jupiter (orbital period shorter than 10 days), TOI-2420\,b, and a warm Jupiter, TOI-2485\,b. We performed a joint analysis using a wide variety of spectral and photometric data in order to characterize these planetary systems. We found that TOI-2420\,b has an orbital period of P$_{\rm b}$=5.8 days, a mass of M$_{\rm b}$=0.9 M$_{\rm J}$ and a radius of R$_{\rm b}$=1.3 R$_{\rm J}$, with a planetary density of 0.477 \gc; while TOI-2485\,b has an orbital period of P$_{\rm b}$=11.2 days, a mass of M$_{\rm b}$=2.4 M$_{\rm J}$ and a radius of R$_{\rm b}$=1.1 R$_{\rm J}$ with density 2.36 \gc. With current parameters, the migration history for TOI-2420\,b and TOI-2485\,b is unclear: the high-eccentricity migration scenarios cannot be ruled out, and TOI-2485\,b's characteristics may rather support this scenario.

To establish a self-sustained human presence in space and to explore deeper into the solar system, extensive research has been conducted on In-Situ Resource Utilization (ISRU) systems. Past studies have proposed and researched many technologies to produce oxygen from regolith, such as carbothermal reduction and water extraction from icy regolith, to utilize it for astronauts' life support and as the propellant of space systems. However, determining the most promising technology remains challenging due to uncertainties in the lunar environment and processing methods. To better understand the lunar environment and ISRU operations, it is crucial to gather more information. Motivated by this need for information gathering, this paper proposes a new ISRU plant architecture integrating carbothermal reduction of dry regolith and water extraction from icy regolith. Two different hybrid plant architectures integrating both technologies (1) in parallel and (2) in series are examined. The former involves mining and processing in both a Permanently Shadowed Region (PSR) and a peak of eternal light in parallel, while the latter solely mines in a PSR. In this series hybrid architecture, the dry regolith tailings from water extraction are further processed by carbothermal reduction. This paper conducts a comparative analysis of the landed mass and required power of each plant architecture utilizing subsystem-level models. Furthermore, based on uncertain parameters such as resource content in regolith, the potential performance range of each plant was discovered through Monte Carlo simulations. The result indicates the benefit of the series hybrid architecture in terms of regolith excavation rate, while its mass cost seems the highest among the studied architectures., Comment: 26 pages, 21 figures, 7 tables, under review by Acta Astronautica

We present the validation of two TESS super-Earth candidates transiting the mid-M dwarfs TOI-6002 and TOI-5713 every 10.90 and 10.44 days, respectively. The first star (TOI-6002) is located $32.038\pm0.019$ pc away, with a radius of $0.2409^{+0.0066}_{-0.0065}$ \rsun, a mass of $0.2105^{+0.0049}_{-0.0048}$ \msun, and an effective temperature of $3229^{+77}_{-57}$ K. The second star (TOI-5713) is located $40.946\pm0.032$ pc away, with a radius of $0.2985^{+0.0073}_{-0.0072}$ \rsun, a mass of $0.2653\pm0.0061$ \msun, and an effective temperature of $3225^{+41}_{-40}$ K. We validated the planets using TESS data, ground-based multi-wavelength photometry from many ground-based facilities, as well as high-resolution AO observations from Keck/NIRC2. TOI-6002 b has a radius of $1.65^{+0.22}_{-0.19}$ \re\ and receives $1.77^{+0.16}_{-0.11} S_\oplus$. TOI-5713 b has a radius of $1.77_{-0.11}^{+0.13} \re$ and receives $2.42\pm{0.11} S_\oplus$. Both planets are located near the radius valley and near the inner edge of the habitable zone of their host stars, which makes them intriguing targets for future studies to understand the formation and evolution of small planets around M-dwarf stars.

This work shows a procedural method for extracting object heights from LiDAR and aerial imagery. We discuss how to get heights and the future of LiDAR and imagery processing. SOTA object segmentation allows us to take get object heights with no deep learning background. Engineers will be keeping track of world data across generations and reprocessing them. They will be using older procedural methods like this paper and newer ones discussed here. SOTA methods are going beyond analysis and into generative AI. We cover both a procedural methodology and the newer ones performed with language models. These include point cloud, imagery and text encoding allowing for spatially aware AI.