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Androgen loss accelerates brain tumour growth via HPA axis activation

Deep learning based cricket batting shot classification and performance analysis using computer vision

Potential energy curves and transition dipole moments of the 51 lowest electronic states of the N2 molecule

This study presents Born–Oppenheimer energies and transition dipole moments of the 51 lowest electronic states of the N2 molecule as a function of internuclear distance in the interval between 1.35 and 10 bohrs. The electronic states are of the total electronic spin S = 0, 1, 2, and 3 dissociating toward the lowest dissociation limits. The obtained potential energy curves are employed to compute the vibrational energy levels of these states, with the aim of improving the reference database for this molecular system, which will serve as a basis for future investigations related to nitrogen plasma formation.

Leishmaniasis

Achieving ultrastable piezoelectric response over a wide temperature range in BF–BT ceramics via phase-domain-defect regulation

Developing lead-free piezoelectric materials with high thermal stability is essential for sensing and actuation applications in harsh environments. In this work, trace amounts of lithium niobate (LiNbO3) were introduced into the 0.75BiFeO3–0.25BaTiO3 system to tailor the phase structure, lattice distortion, and defect chemistry. The substitution of Li+/Nb5+ for A-/B-site elements promotes partial rhombohedral (R) to tetragonal (T) phase transition, enhances tetragonal distortion, reduces oxygen vacancy formation, and simultaneously strengthens phase separation. This slightly weakens long-range ferroelectric order and facilitates the formation of a suitable amount of nanodomains. The optimized composition (x = 0.001) exhibits highly stable piezoelectric constant (d33) around 107 pC/N (at room temperature) over a broad temperature range of 30–322 °C, with fluctuations below 10%, and retains a high piezoelectric response (d33 ∼ 103 pC/N) even after aging at 300 °C for 12 h. This enhanced stability stems from the balanced interplay among the thermal disturbance de-pinning effect, thermally driven dipole-moment attenuation effect, and thermally induced ferroelectric domain disorder effect. This study offers an effective defect-phase-domain design strategy for realizing lead-free piezoelectric ceramics with high thermal reliability.

Structural connectome and cognitive performance in young stroke survivors

Dynamical phase transitions in Kob–Andersen model investigated by trajectory energy-biased ensemble method

Statistical mechanics of far-from-equilibrium systems requires trajectory-based ensembles rather than static configurations. Biasing fields conjugate to dynamical activity (s-field) and time-integrated trajectory energy (g-field) provide powerful tools for probing rare dynamical states. While s-ensemble studies have demonstrated first-order dynamical phase transitions in glass-forming models, it remains unclear whether energy-only biasing can induce transitions in kinetic observables to which it is not directly coupled. Here, we investigate this question in the Kob–Andersen binary Lennard–Jones model by constructing the two-dimensional (T, g) phase diagram using transition path sampling. We identify a first-order dynamical phase transition line separating active and inactive trajectory phases, confirmed by diverging dynamical susceptibilities and bimodal order parameter distributions. Binder cumulant analysis, enabled by Gaussian process regression and large-deviation relations, locates the upper critical point (Tuc, guc) ≃ (0.675, 1.9 × 10−3). We further demonstrate that g-ensemble glasses are structurally indistinguishable from conventionally quenched glasses, while intermediate scattering functions confirm that the active–inactive transition is purely dynamical in nature. Spatial analysis further reveals that mobile particles form a system-spanning cluster in the active phase but remain fragmented in the inactive phase, consistent with the dynamical facilitation picture. These results demonstrate that energy-landscape biasing alone is sufficient to drive first-order dynamical phase transitions in an atomistic glass-forming model, establishing the g-ensemble as a controlled framework that connects the thermodynamic potential energy landscape with dynamical arrest phenomena central to kinetic theories of the glass transition.

Bronchial Anthracosis

Study of linear electro-optical effects in silicon materials under the action of continuous stress field

To investigate the mechanism of the linear electro-optic effect in strained silicon and advance the practical application of silicon-based optical modulators, this paper addresses the limitations of existing theoretical models due to their lack of continuous strain tuning capability. By employing a self-designed uniaxial stress setup, continuous and tunable strain was applied to silicon, enabling systematic measurement of the relationship between the output electro-optic signal and strain. Through controlled variable analysis, the synergistic influence of strain and modulation electric fields was qualitatively examined. Signal separation was performed by exploiting the polarization dependence differences between the plasma dispersion effect and the Pockels effect. The results indicate that the electro-optic signal primarily originates from the plasma dispersion effect, and both this effect and the contribution from the Pockels effect enhance with increasing strain. When strain reaches the order of 10−4, the electro-optic tensor of silicon attains a magnitude of approximately 0.01 pm/V. An experimental formula describing the variation of the second-order nonlinear susceptibility tensor with strain is also provided. This study offers direct experimental evidence for elucidating the mechanism of the linear electro-optic effect in strained silicon and holds significant implications for accelerating the integration of silicon-based electro-optic modulators.

Synergistic engineering of fluorine doping FexMn1-xMoO4/graphene heterojunction as ultrahigh-rate anode for LIBs

Acoustic shock wave impact on stability aspects of crystal structure–functional properties—A case study of corundum-type structure of α-Cr2O3 nanoparticles

Subjecting solid-state materials to shock conditions is one of the most familiar subjects in condensed matter research, helping to understand the usual and unusual behaviors of materials through their phase transitions and functional property changes. Highly stable materials under extreme conditions are typically considered for technological applications, and high-pressure researchers always try to find such materials to build a world of strong and stable materials science. In this context, we are inclined to investigate the corundum-type structure of α-Cr2O3 NPs under dynamic acoustic shock conditions and compare it with previously reported α-Fe2O3 NPs. From the structural point of view, under acoustic shock conditions, α-Cr2O3 NPs remain the same with the R3-c space group even at the 200-shocked condition, whereas in α-Fe2O3, the α-Fe2O3 (R3-c)-to-Fe3O4 (Fd-3m) transition is observed. For both these oxides, supporting evidence for the results is also presented via vibrational, optical, magnetic, thermal, electrical, and electrochemical properties. In addition, a possible mechanism is proposed, implementing a thermal conductivity-driven superheating approach to justify the stability order for both oxides. According to the observed static compression results and the current acoustic shock wave-induced results of these two oxides, the structural stability order is α-Cr2O3>α-Fe2O3. Due to the impressive results of structural stability under static and dynamic shock conditions, α-Cr2O3 is a more suitable candidate for extreme conditions such as aerospace and defense applications.

Remuscularizing the Failing Human Heart

Modeling chirality transfer at graphene–liquid crystal interfaces driven by non-collinear graphene corrugations

Graphene exhibits optical chirality only when its in-plane mirror symmetries are broken—by strain corrugation, buckling, interlayer twist, chemical corrugation, or planar patterning—yet the microscopic route by which such interfacial handedness is transferred to adjacent otherwise achiral soft matter needs to be understood in full theoretical depth. We present a symmetry-based, predictive model showing that non-collinear corrugations of a graphene sheet generate a geometric pseudoscalar that acts as a chiral field at the graphene–liquid crystal (LC) interface. This field deracemizes configurationally achiral smectic-A LC molecules aligned by π–π stacking on the graphene surface and, under an out-of-plane electric field, drives a surface electroclinic effect (ECE)—a measure of chirality in the LC. The framework yields clear predictions: a single-pole frequency response; a rise-then-saturate behavior of the electroclinic coefficient with increasing graphene corrugation amplitude; and a monotonic increase of the cutoff frequency with roughness. The predictions are consistent with previously reported experimental observations, including graphene circular-dichroism studies and our companion LC measurements. The model explains why ultraflat graphene is optically achiral, yet strained graphene induces a robust interfacial ECE, and it provides practical design knobs for engineering chiral responses in 2D/soft-matter hybrids, opening a broadly applicable route to interfacial chirality control.

Privacy preservation of EHR by data anonymization and federated learning for IoT based smart city application in healthcare

Vibrational energy transfer of water at interfaces mediated by Fermi resonance

Combining neural network-based molecular dynamics simulations with the mixed quantum/classical approach, we elucidate the vibrational energy transfer pathways of interfacial OH groups (3115–3285 cm−1). This study reveals that intermolecular transfer exhibits the slowest kinetics due to the attenuated dipole–dipole coupling at interfaces, while reorientation, intramolecular, and Fermi-resonant pathways proceed faster. Notably, Fermi resonance largely influences the observed energy transfer dynamics. The overall time is in agreement with experimental measurements. These findings establish Fermi resonance as a critical factor in the vibrational energy transfer near 3200 cm−1 at the gas/water interface.

Stem-Cell–Derived Biologic Ventricular Assist Tissue in Heart Failure

Evolution of the near-infrared-to-ultraviolet model dielectric function of InAs from room temperature to 250 °C determined by spectroscopic ellipsometry

We present a model dielectric function composed of critical point functions in order to parameterize the temperature and wavelength dependencies of the dielectric function of InAs. This model is based on Adachi’s critical point model, with simple wavelength-dependent analytical functions whose parameters change linearly with temperature. The calculated dielectric function at room temperature is in excellent agreement with previously published data. We apply this model in the spectral range of 0.7–5 eV and in the temperature range of room temperature to 250°C with in situ spectroscopic ellipsometry measurements on an InAs substrate. Spectroscopic measurements were performed continuously while slowly ramping sample temperature in a stepwise manner in the controlled ambient environment of an atomic layer deposition system. We find that our model matches excellently with all experimental data with deviations less than 2% in pseudoepsilon. Our model permits smooth interpolation of the dielectric function of InAs for any intermediate temperature in the range studied and therefore can be used to monitor temperature, for example, during thin film deposition processes by in situ spectroscopic ellipsometry. We propose that this model can be applied to other semiconductors as well as wider temperature ranges.

Quantitative assessment of inspiratory loading on postprandial glycemia and metabolic response in healthy adults

Quantum and structural effects captured via a statistical method: The SACM applied to HCN and HNC colliding with CO

This study spotlights the statistical adiabatic channel model as an efficient and accurate method for deriving low-temperature (de)-excitation rate coefficients for collisions induced by heavy projectiles. For such systems, fully quantum treatments become intractable, while quasi-classical methods fail at low temperature. Here, we demonstrate that the statistical adiabatic channel model overcomes these limitations by combining statistical sampling with an adiabatic channel representation. Its application to the HCN and HNC isomers colliding with CO yields rate coefficients in quantitative agreement with full quantum results benchmarked for the lowest total angular momentum. These systems are relevant for modeling cometary comae, where reliable molecular data remain scarce. Remarkably, this approach also reproduces near-resonant energy transfer and isomeric effects, demonstrating that essential quantum and structural features can be captured within a statistical framework.

Getting Serious about Tickborne Diseases — Shifting Research Priorities