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The record of Scalichnus ichnofabrics in ancient fluvial settings and its paleoecological significance

Computing excited eigenstates using inexact Lanczos methods and tree tensor network states

To understand the dynamics of quantum many-body systems, it is essential to study excited eigenstates. While tensor network states have become a standard tool for computing ground states in computational many-body physics, obtaining accurate excited eigenstates remains a significant challenge. In this work, we develop an approach that combines the inexact Lanczos method, which is designed for efficient computations of excited states, with tree tensor network states (TTNSs). We demonstrate our approach by computing excited vibrational states for three challenging problems: (1) 122 states in two different energy intervals of acetonitrile (12-dimensional), (2) Fermi resonance states of the fluxional Zundel ion (15-dimensional), and (3) selected excited states of the fluxional and very correlated Eigen ion (33-dimensional). The proposed TTNS inexact Lanczos method is directly applicable to other quantum many-body systems.

Mycochemistry, antioxidant activity and anticancer potentiality of ethyl acetate extract of Daldinia eschscholtzii against A549 lung cancer cell line

Interlayer multi-level orbital coupling in 2D materials: Beyond the two-level paradigm

The interlayer orbital interaction (IOI) of two-dimensional (2D) materials and their heterostructures triggers diverse property modifications, driving advancements in interlayer engineering. Previous investigations into IOI have primarily relied on a two-level interlayer interaction framework (one energy level per layer), which is insufficient for fully capturing band edge evolutions—even in prototypical 2D materials transitioning from monolayers to multilayers. The underlying reason lies in the multi-level nature of orbitals: taking the MoS2 monolayer as a paradigm, the pz orbitals of the two sulfur atoms (which dominate interlayer IOI) contribute to the wavefunctions of three energy levels (rather than one), enabled by pz–dz2–pz coupling along the S–Mo–S chemical bonds. Consequently, these three energy levels within a single layer can interact with a target energy level of interest (e.g., a band edge) in adjacent layers, provided they share the same orbital character. This gives rise to the “n-act-on-one” IOI mechanism, the core of multi-level interlayer interaction. Notably, this multi-level characteristic is inherent to general 2D materials. To address this, we extend the interlayer interaction model to a multi-level framework. This multi-level perspective offers deeper insights into the properties of 2D materials and helps property tuning from a perspective of combining intra- and interlayer orbital interactions.

Spatial analysis and health implications of micro rubber and vanadium in urban street dust in Northwest of Iran

Packing and ejection of a semiflexible polymer in a capsid: Effect of helicity

The translocation of semiflexible polymers into confined geometries is central to many biological processes, including viral genome packaging. Understanding how helicity influences these processes offers new mechanistic insights into the role of torsional elasticity in confined semiflexible polymers. Here, we investigate how torsional rigidity influences the packing and ejection dynamics of a helical polymer confined within a spherical capsid. We find that torsional stiffness has a non-monotonic effect on the total packing time: a small but finite torsional rigidity minimizes the packing time, while further increases in stiffness first slow down and then accelerate the packing process. This behavior arises from a competition between the formation of spool-like configurations, which favor efficient packing, and the increase in persistence length, which hinders polymer folding under confinement. Notably, this non-monotonicity vanishes when confinement interactions are removed, underscoring the key role of spatial constraints. In addition, structural analyses reveal that torsional stiffness promotes coiled or spooled conformations, resembling those observed in bacteriophage DNA. Even in the absence of torsion, moderate bending stiffness combined with confinement can induce partial spooling, highlighting the importance of geometric and motor-driven effects. In contrast, ejection slows down monotonically with increasing torsional stiffness, as higher rigidity impedes uncoiling and exit through the pore. These results demonstrate that torsional elasticity critically shapes both packing and ejection, and they offer insights into viral DNA packaging, where polymer mechanics and confinement are intricately coupled.

Selected high-entropy alloys for thin film deposition, with improved mechanical and corrosion properties

High-harmonic generation under electronic strong coupling: A time-dependent combined quantum electrodynamics/quantum chemistry study

The creation of light–matter hybrid states, polaritons, in a cavity offers new intriguing opportunities to manipulate the electronic structure and electron dynamics of atoms and molecules. Here, we investigate the effect of strong electronic coupling between atoms or molecules and field modes of a Fabry–Pérot cavity on High-Harmonic Generation (HHG) spectra within a theoretical model study. We assume that the atom or molecule is driven by an intense classical laser field, giving rise to HHG, while being strongly coupled to quantized cavity modes as described by the Pauli–Fierz Hamiltonian in the framework of molecular quantum electrodynamics. Specifically, as a test case, we first consider a model Hamiltonian of a one-dimensional hydrogen atom coupled to a cavity mode, which can be treated “numerically exact” using grid methods. Furthermore, a hydrogen molecule coupled to a cavity mode is considered and treated within a recently suggested QED-TD-CI (Quantum Electrodynamics Time-Dependent Configuration Interaction) method [Weidman et al., J. Chem. Phys. 160, 094111 (2024)]. The resulting HHG spectra show (i) a suppression of the harmonic cutoff in line with the excitation of quantum light in the cavity and, in some cases, (ii) enhancement of some harmonics of the coupled light–matter system.

Correction: PEGylated liposomal metformin overcomes pharmacokinetic barriers to trigger potent mitochondrial disruption and cell cycle arrest in hepatocellular carcinoma

When dephasing fails: Thermodynamic consequences of decoherence models in quantum transport

Understanding how decoherence influences heat and information flow is essential for realizing the promise of quantum technologies. Two widely used models for incorporating decoherence in quantum transport are the voltage probe (VP), which imposes local charge current conservation, and the voltage–temperature probe (VTP), which also conserves heat current. Although these models are often treated as functionally equivalent, we demonstrate that this equivalence actually exists only under highly symmetric conditions, which may be challenging to achieve experimentally. Under asymmetric coupling or thermal bias, the VTP respects thermodynamic constraints and enforces decoherence in both charge and heat channels, while the VP instead acts as a source or sink of heat. Strikingly, the VP can fail to model decoherence in the heat transport entirely, even with large probe coupling strengths. Using a benzene-based molecular junction as a realistic example, we show that these effects significantly impact the predicted heat transport. These results establish that the VP and VTP models are not interchangeable; only the VTP provides a thermodynamically consistent framework for modeling decoherence in quantum transport.

A swarm intelligence-driven hybrid framework for brain tumor classification with enhanced deep features

When does a nanoparticle become a cluster?

We identify physical criteria to differentiate the behavior of aggregates having a number of atoms N < 104, classifying them as nanoparticles or clusters. This is achieved by investigating finite Lennard-Jones spherical aggregates using molecular dynamics, under equilibrium and non-equilibrium conditions. Ten aggregates ranging from N = 4235 to N = 73 atoms are analyzed at equilibrium, introducing an energetic criterion based on local potential energy profiles and a structural criterion based on the pair distance distribution. Two distinct size regimes emerge: a scalable regime characterized by linear variations in the microscopic properties and by a homogeneous internal region, and a non-scalable regime presenting abrupt changes in the microscopic observables, such as steep local potential energy gradients and dominance of surface atoms. Non-equilibrium sublimation simulations at elevated temperatures suggest a third criterion, denoted non-equilibrium criterion, where aggregates initially sublimate at a linear rate before sharply accelerating upon reaching a threshold size. This occurs at the transition between scalable and non-scalable regimes and is confirmed by instantaneous local potential energy profiles. To reconcile with existing size-related terminology, we categorize aggregates in the scalable linear regime as nanoparticles and those in the non-scalable nonlinear regime as clusters. Crucially, all three criteria independently identify the same size threshold, underpinning the universal role of the local potential energy environment in controlling the aggregate structure and dynamics. These findings, explicitly obtained with pairwise-additive, short-range, and isotropic interactions, address the ambiguity with the distinction between nanoparticles and clusters, providing new insights that clusters must be explicitly treated as finite systems and are dominated entirely by surface atoms and interactions.

Estimation of protein content in wheat samples using NIR hyperspectral imaging and 1D-CNN

Machine learning many-body potentials for charged colloids in primitive 1:1 electrolytes

Effective interactions between charged particles dispersed in an electrolyte are most commonly modeled using the Derjaguin–Landau–Verwey–Overbeek potential, where the ions in the suspension are coarse-grained out at mean-field level. However, several experiments point to shortcomings of this theory, as the distribution of ions surrounding colloids is governed by nontrivial correlations in regimes of strong Coulomb coupling (e.g., low temperature, low dielectric constant, high ion valency, and high surface charge). Insight can be gained by explicitly including the ions in simulations of these colloidal suspensions, even though direct simulations of dispersions of highly charged spheres are computationally demanding. To circumvent slow equilibration, we employ a machine-learning (ML) framework to generate density-dependent ML potentials that accurately describe the effective colloid interactions at given system parameters. These ML potentials enable fast simulations and make large-scale simulations of charged colloids in suspension possible, opening the possibility for a systematic study of their phase behavior, in particular gas–liquid and fluid–solid coexistence.

Heuristic computational approach for nonlinear reaction–diffusion kinetics in catalytic systems

Quantitative structure–spectrum relationship in uranyl complexes: Density functional theory and Raman insights into sodium ions-modulated coordination evolution

Uranium extraction from seawater is a promising strategy to address terrestrial uranium depletion. However, the complex marine environment induces diverse uranium speciation and coordination structures, creating substantial challenges for uranium detection and extraction. Herein, we establish the quantitative structure–spectrum relationship through correlating the uranyl–oxygen bond lengths and symmetric stretching frequencies in typical uranyl complexes by employing density functional theory calculations. Moreover, the structural evolution of uranyl in sodium carbonate solutions under acidic to weakly alkaline conditions is investigated in combination with Raman spectroscopy experiments, demonstrating a linear correlation between the uranyl–oxygen bond lengths and vibrational frequencies in sodium-containing complexes, which verifies and extends the applicability of Badger’s rule in uranyl systems. Atomic-level analyses further reveal that sodium ions modulate ligand charge distributions via strong electrostatic interaction, resulting in weakened uranium–oxygen bonds and enhanced structural stability of the uranyl complexes. These findings deepen the understanding of the structure–spectrum relationship in complex solutions and provide insights for uranium resource exploration in seawater.

Correction: Evaluating the COVID-19 vaccination program in Japan, 2021 using the counterfactual reproduction number

Alchemical diastereomers from antisymmetric alchemical perturbations

The energy difference between two iso-electronic systems can be approximated by the first order Hellmann–Feynman derivative with respect to the linear alchemical coupling parameter, evaluated using the electron density of the corresponding averaged Hamiltonian. This approximation is exact up to third order because even-order contributions cancel out. This finding holds for any iso-electronic compound pair (dubbed “alchemical diastereomers”), regardless of differences in configuration, composition, or energy, and consequently, relative energy estimates for all possible iso-electronic alchemical diastereomer pairs require only O(1) self-consistent field cycles for any given averaging reference Hamiltonian. We discuss the relation to the Verlet algorithm, alchemical harmonic approximation (AHA) [Krug et al., J. Chem. Phys. 162, 044101 (2025)], relative properties such as forces, ionization potential or electron affinities, and Levy’s formula for relative energies among iso-electronic systems that uses the averaged electron density of the two systems [Levy, J. Chem. Phys. 70, 1573 (1979)]. Density functional theory based estimates accurately reflect trends in the charge-neutral iso-electronic diatomic molecule series with 14 protons (N2, CO, BF, BeNe, LiNa, HeMg, HAl), with systematically increasing errors. Using alchemical Hellmann–Feynman derivatives for toluene, we demonstrate the concept’s broader applicability by estimating relative energies for all 36 possible alchemical diastereomer pairs from vertical iso-electronic charge-neutral antisymmetric BN doping of toluene’s aromatic ring, with mean absolute errors of a few milli-Hartrees.

Sexual dysfunction in women who received breast cancer treatment: a cross-sectional study

Enhancement of nuclear spin transitions as a resonance effect of isotope substitution

Mixing of different components of the total nuclear spin in the rovibrational states of isolated molecules is extremely weak. It has only been observed in hyperfine spectra for few systems, including S2Cl2, SiF4, PH3, and SF6. We perform variational calculations of nuclear quadrupole interactions in the rotational spectra of S2Cl2 and CH2Cl2 and analyze the effects of breaking the molecular symmetry by isotopic substitution of one of the chlorine atoms. This symmetry breaking significantly enhances the mixing of nuclear spin states and produces a distinct spin polarization pattern with opposite spin orientations on the different isotopes. This enhancement arises as a resonance effect driven jointly by differences in isotopic masses and nuclear quadrupole coupling constants and gives rise to electric and magnetic dipole transitions between states with different relative orientations of the nuclear spin.