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Money and Misdiagnosis

Hopping conduction in GeSiSn alloys: Impact of structural disorder on electrical transport

Temperature-dependent charge transport in epitaxial GeSiSn films with varying thicknesses and Si and Sn content, grown on Ge/Si(001) substrates, was investigated using admittance spectroscopy. The conductance exhibits a crossover from Mott variable-range hopping at low temperatures to thermally activated conduction at higher temperatures. Below 150 K, carriers move via localized states in the band tails, with hopping parameters governed by the density and spatial distribution of disorder-induced states. Increasing nominal Sn concentration and thickness enhances structural disorder and Sn segregation, leading to a higher density of states and reduced hopping length. Scanning capacitance microscopy reveals variations in charge-carrier concentration in high-Sn films, indicating the presence of coexisting p-type and n-type regions at the microscale, consistent with compositional fluctuations, Sn segregation, and microstrain. These results demonstrate that transport in GeSiSn alloys is primarily dominated by disorder-assisted hopping at low temperatures, establishing a quantitative link between microscopic disorder and macroscopic electrical response in metastable group-IV semiconductors.

Lung cancer in women emerges as a distinct disease

Decoding selective auditory attention to musical elements in ecologically valid music listening

Effects of divalent cations on diffusion dynamics of biological water confined between lipid membranes

Biological water is an ionic solution containing both monovalent and divalent ions. However, the effects of divalent ions on the dynamics of biological water remain largely unknown. Here, we investigate how the transport dynamics of water molecules nanoconfined between lipid membranes depends on the concentration of calcium (Ca2+) and magnesium (Mg2+) ions by using molecular dynamics simulations and the generalized transport equation for biological water. We find that the diffusion coefficient of biological water monotonically increases with Ca2+ ion concentration but exhibits a largely opposite, non-monotonic dependence on Mg2+ concentration. The deviation of the water molecules’ displacement distribution from the Gaussian also shows a distinct dependence on the concentrations of Mg2+ and Ca2+. These contrasting behaviors originate from the different hydration radii of these divalent ions and their distinct effects on the interfacial structure and dynamics of biological water. The relaxation of the lateral displacement distribution of water molecules toward a Gaussian is determined by the time-correlation function of diffusion coefficient fluctuations, whose relaxation time increases with salt concentrations. The primary source of the lateral diffusion coefficient fluctuation is thermal motion of water molecules in the longitudinal direction, along which microscopic environments surrounding a water molecule, including the functional groups of lipid membrane and ion concentrations, drastically change.

Neoadjuvant GOLP in Intrahepatic Cholangiocarcinoma

Study on catastrophic optical damage behavior of GaN-based high-power blue laser diodes

Facet degradation in blue GaN-based laser diodes operating at output optical powers exceeding 17 W is investigated. Facet coating failure in large optical cavity devices is shown to originate from an inhomogeneous temperature distribution at the front facet caused by non-uniform optical intensity across the emitting region under high-power operation. Localized heat accumulation leads to partial melting of the epitaxial material near the facet, and the resulting thermal stress induces coating delamination and spalling, constituting catastrophic optical damage (COD). Notably, the coating structure and interfaces within the damaged regions remain well defined after COD, indicating that failure is initiated by localized thermal degradation of the epitaxial material, which subsequently triggers coating failure. These results demonstrate that suppressing optical intensity non-uniformity or reducing the overall junction temperature is critical for mitigating facet COD in high-power GaN-based laser diodes.

Male sex hormone loss aids brain tumour growth

Novel hybrid machine learning-based prediction of building space heating load: a comprehensive study

Nucleation of NaCl crystals from solution: Rate prediction and influence of noisy order parameters on the committor

We report on a transition interface sampling study of the homogeneous crystal nucleation of NaCl from supersaturated solutions under ambient conditions. We predict the rate and the free energy of the nucleation process and show that they are in line with previous results and with classical nucleation theory. While adequate for rate calculations, the order parameter used exhibits strong temporal fluctuations, which lead to an apparent inconsistency between forward- and backward-projected committor functions. By introducing a temporally smoothed order parameter, we restore consistency in the committor and obtain a more faithful representation of progress along the nucleation pathway. The optimal smoothing window corresponds to a timescale of ∼3 ns, suggesting that only ion attachment events persisting on nanosecond timescales contribute to crystal growth, whereas faster fluctuations reflect transient rearrangements. These findings highlight the importance of temporal persistence, in addition to structural criteria (crystallinity and coordination), for defining meaningful order parameters in nucleation studies.

Colles’ Fracture

Stabilizing low-loss pyrochlore phase for high-efficiency energy storage

Bismuth-based pyrochlore phases, as linear dielectrics, offer a compelling combination of ultralow loss, moderate permittivity, and high breakdown strength, rendering them promising for dielectric energy storage applications. However, the advancement of related research is impeded by the inherent thermodynamic instability in the Bi2O3–TiO2 phase diagram, which makes the synthesis of phase-pure Bi2Ti2O7 particularly challenging. In this work, we demonstrate that the stability of Bi2Ti2O7-based phase is significantly enhanced through careful control of the thermal processing temperature. The resulting materials, therefore, show ultralow dielectric loss and reduced polarization switching hysteresis as well as improved breakdown field. Consequently, a high energy density of 65.5 J/cm3 and an excellent energy efficiency of 84.3% are achieved concurrently. The findings reported herein help to elucidate the relationship between pyrochlore structure stabilization and thermal treat process, thereby providing an effective way for improving the energy storage performance of Bi2Ti2O7-based thin films.

Human norovirus GII genotypic diversity in Gwangju, South Korea, based on ORF1-ORF2 junction (RdRp-VP1) analysis from 2020 to 2024

Estimation of protein melting temperatures using small-ladder replica exchange simulations

The unfolding or melting temperature (TM) is a central quantity to characterize the stability of proteins and other biopolymers. The accurate prediction of protein melting temperatures by molecular mechanics force field simulations is highly desirable for many biophysical and biotechnological applications. Since the time scales for protein (un)folding are hardly accessible in conventional molecular dynamics simulations, enhanced sampling techniques such as Temperature Replica Exchange Molecular Dynamics (TREMD) are typically employed. However, TREMD simulations are computationally very demanding, especially if large temperature ranges need to be covered. In addition, if TM is initially unknown, setting up TREMD simulations is often challenging. To find the optimal initial conditions for such simulations, we describe their performance using a theoretical model, which we validate on a minimalistic Markov chain Monte Carlo simulation setup. In an effort to reduce the computational demand, we have investigated the possibility of using small sets of TREMD temperature ladders placed iteratively in the vicinity of a TM estimate. Different TREMD setups were extensively tested on the fast-folding protein chignolin. We found that appropriate starting conformations lead to significantly faster convergence. Furthermore, we found that, in practice, combining multiple small temperature ladders can be advantageous in comparison to a single temperature ladder. Based on our findings, we formulate practical recommendations on how to setup TREMD for protein melting with optimal efficiency.

Hematopoietic Stem-Cell Gene Therapy for Cystinosis

Silicon-based metamaterial selective emitter for thermophotovoltaic applications

In this work, we present the design and optimization of a silicon-based selective emitter (SE) for thermophotovoltaic (TPV) systems with enhanced spectral efficiency. The proposed SE combines a broadband infrared absorber, a periodic triangular arrays of heavily doped silicon in this case, and a one-dimensional (1D) dielectric photonic crystal filter alternating silicon and silicon dioxide (Si/SiO2) layers. Both parts are integrated within a single monolithic structure that forms the selective emitter. The broadband absorber ensures high emissivity in the in-band region (i.e., for wavelengths shorter than the bandgap wavelength of the TPV cell), while the photonic crystal filter selectively suppresses long-wavelength emission in the out-of-band region (i.e., for wavelengths longer than the bandgap wavelength of the TPV cell), resulting in a spectrally selective emission profile over a wide infrared range up to 8 μm. To enhance the performance of the structure, a Particle Swarm Optimization algorithm was implemented to optimize the thicknesses of the Si/SiO2 multilayers. The optimized design demonstrates a spectral efficiency improvement exceeding 20% compared to conventional quarter-wave photonic crystal structures, and more than 45% relative to a blackbody emitter at an operating temperature of 1500 K. Beyond the specific structure investigated in this study, the proposed optimization framework provides a general and flexible methodology that can be readily extended to other broadband emitters and tailored to different TPV cell bandgaps.

The homozygous founder Psmb8 variant of Nakajo-Nishimura syndrome/proteasome-associated autoinflammatory syndrome causes panniculitis-associated lipoatrophy and a shortened lifespan in mice

A numerically exact, non-Markovian, non-Gaussian noise model for open quantum system dynamics

We develop a multichannel random-telegraph-noise hierarchical-equations (RTN–HE) framework for interacting multiqubit systems to describe non-Markovian, intrinsically non-Gaussian open quantum system dynamics driven by classical stochastic processes. Starting from the stochastic Liouville equation, we derive a systematic multi-channel generalization of the Shapiro–Loginov identity and construct a closed hierarchy of mixed system–noise moments. Owing to the dichotomic algebra of telegraph processes, the hierarchy terminates exactly, embedding the non-Markovian reduced dynamics into a finite-dimensional linear system of ordinary differential equations without stochastic trajectory sampling. An equivalent formulation in the noise-configuration basis yields a tensorized Liouvillian with explicit Kronecker-product structure, enabling sparse and efficient propagation on an enlarged state space. We further show that thermal detailed balance can be enforced consistently through a constant counterterm, without modifying the homogeneous generator, establishing thermodynamically controlled long-time behavior within the RTN–HE formalism. The framework is illustrated in two distinct settings: excitation energy transfer in a reduced Fenna–Matthews–Olson complex, where RTN–HE provides a compact stochastic surrogate to hierarchical equations of motion dynamics, and Bell-state storage in a quantum teleportation protocol, where the model enables a direct comparison between non-Gaussian telegraph noise and Gaussian processes matched at the level of second-order correlations. These results position RTN–HE as a controlled theoretical approach for isolating and quantifying the dynamical consequences of finite memory and higher-order moment noise statistics in multi-site open quantum systems.

Patching Up Damaged Hearts

Pressure-threshold explosive cathode processes as the dominant source of a high-density plasma in nanosecond air discharges

We report a pressure-threshold phenomenon in nanosecond air discharges: explosive cathode processes become the dominant source of a dense highly ionized plasma at air pressures above ∼100 Torr. Picosecond laser imaging reveals that these explosive processes, while competing with air ionization, result in the ejection of cathode material over a time scale shorter than 1 ns to create a plasma with electron densities as high as ≈6 × 1019 cm−3, significantly exceeding values achievable through air ionization alone. The explosive processes exhibit a sharp onset, disappearing when the air pressure drops by as little as tens of Torr relative to 100 Torr. Our findings demonstrate that, at high air pressures, cathode vaporization—rather than gas ionization—initiates the generation of such a dense plasma and enables electric spark formation. At intermediate pressures, below ∼100 Torr, yet above vacuum conditions, this explosive mechanism is suppressed, and the discharge transitions to a regime governed by volumetric gas ionization. This behavior contrasts with vacuum discharges, where cathode material is the dominant plasma source. The revealed threshold mechanism is crucial for controlling plasma in applications ranging from nanoparticle synthesis to pulsed power systems.