Lili Zhang

Domain shift and scarcity in target domain annotations constrain the generalizability of liver magnetic resonance imaging (MRI) segmentation models. To overcome these challenges, we propose two strategies: adaptive unfreezing transfer learning (AU-TL) for cross-domain adaptation and residual-connected multi-fidelity fusion (R-MFF) for integrating low-fidelity public data and high-fidelity (HF) private data. AU-TL and R-MFF reduced the annotation requirements by 78.6% and 71.4%, respectively, while maintaining their competitive segmentation performance. This finding shows that RMFF is particularly advantageous when target domain annotations are extremely limited, whereas AU-TL exhibits a higher performance as more annotated data become available. This finding demonstrates the complementary advantages of these models under different levels of annotation availability.

Coulomb/exchange integrals in first-principles-calculation are Cauchy-integrals. This paper presents a study on this issue. First, to overcome the long computation-time caused by evaluating multiple Riemann-sums for Coulomb/exchange integrals, we show that their convergence is same as the equivalent-Coulomb/exchange integrals of a point-charge with an electron-cloud and a mixed-electron-one, respectively. This reduction transforms the original six-dimensional Riemann-sums into three/two-dimensional ones, drastically cutting the computation-time and allowing the integrand-singularities to be approached as possible. Using the representative hydrogen-wave-functions as the initial-ones, we calculate the corresponding the equivalent-Coulomb/exchange integrals, and show that the integrals are convergent, but a general initial-wave-functions does not guarantee the convergence. Therefore, verifying convergence for selected initial-wave-functions is a prerequisite for ensuring the reliability of first-principles-calculations. Furthermore, as the step-size of Riemann-sum increases, the relative-deviations increase significantly. Hence, the selection of step-sizes and the associated cumulative-deviation analysis are another key factor for the credibility of the computational results.

Based on first-principles calculations, this study systematically investigated the evolution of structural stability, electronic structure, and bulk photoelectric properties of K(Ta _0.5 Nb _0.5 )O ₃ (KTN) under biaxial strain ranging from −30% to 30%.

This study, based on first-principles density functional theory calculations, explores the stability, electronic structure, and optical properties of the Sc2CF2/WS2 heterostructure, with particular emphasis on analyzing its properties under strain effects. Results show it has an indirect bandgap of 1.416 eV—smaller than 1.886 eV of Sc2CF2 and 2.311 eV of WS2 monolayers—and adopts a Z-scheme heterojunction. A 7.861 eV built-in electric field from Sc2CF2 to WS2 promotes efficient electron transfer. Compared with monolayers, it has significantly enhanced optical absorption: Its ultraviolet absorption coefficient reaches 17.9 × 105 cm−1 (250.9% higher than Sc2CF2) and visible-region absorption coefficient is 0.86 × 105 cm−1 (16.2% higher than Sc2CF2). At pH = 0, its band edges cross water’s redox potential, enabling hydrogen/oxygen evolution. For −6% to 6% biaxial strain: −6% to −3% compressive strain turns it into type-I, which is bad for photocatalysis; −2% to 2% retains Z-scheme, suitable for pH = 0 photocatalysis with a maximum built-in electric field of 7.927 eV at −1% strain; and 3% to 6% shifts band edges upward, suitable for pH = 7 while preserving Z-scheme. Moreover, strain engineering further enhances the optical absorption coefficient. These findings confirm its excellent photocatalytic performance, validate strain engineering, and guide MXene/transition metal dichalcogenides-based photocatalyst design.

This study combines the Lattice Boltzmann method with molecular dynamics simulations to investigate the inertial migration of toroid-like and worm-like micelles in rectangular nanochannels at low Reynolds numbers (Re) ranging from 0.000 075 to 0.014. We identify the critical Re for micelle breakage and analyze the equilibrium positions of the micelles at various Re. The results indicate that as Re increases, the equilibrium position of the micelles shifts farther from the central axis of the nanochannel. Due to a slight blockage, the equilibrium position of the worm-like micelles is closer to the corners of the nanochannel compared to the toroid-like micelles. Additionally, we observe conformational transitions during migration: toroid-like micelles deform from circular to elliptical shapes, while worm-like micelles adopt semi-toroidal shapes. We verify that the equilibrium position is influenced by Re, blockage ratio, and micelle shapes. These findings clarify the inertial migration behavior of toroid-like and worm-like micelles in nanochannels and provide a theoretical foundation for optimizing micelle-based drug delivery systems.

Reducing the Schottky barrier at the metal–semiconductor interface and achieving Ohmic contact is crucial for the development of high-performance Schottky field-effect transistors. This paper investigates the stability, interface interactions, interlayer charge transfer, and types of Schottky contacts in the graphene/ZnSe heterostructure structure using first-principles methods. It employs biaxial strain as a control mechanism. The results indicate that applying compressive strain increases the barrier and band gap while maintaining n-type contact; whereas tensile strain reduces the n-type barrier to negative values, inducing Ohmic contact and decreasing the band gap. The findings of this study will provide theoretical references for the design and fabrication of field-effect transistors, photodetectors, and other optoelectronic devices.

In this study, we investigated the mechanisms by which reactive oxygen species (ROS) cause oxidative damage to wall teichoic acid (WTA) and lipoteichoic acid (LTA) in two bacterial species: Staphylococcus aureus and Streptococcus pneumoniae. Using molecular dynamics simulations, we found that ROS primarily induce structural damage through dehydrogenation reactions and the cleavage of C–C and C–O bonds. Notably, the teichoic acid (TA) from S. aureus was found to be more susceptible to damage compared to that of S. pneumoniae, which exhibited stronger antioxidant properties due to its ring structure and chemical modifications. The efficiency of damage increased with ROS concentration, following the order, O > O3 > OH, with a maximum of 22.22% C–C bond cleavage observed at the highest concentration. In addition, the patterns of damage in the TA of these two bacterial species were significantly different. In S. aureus, WTA damage was predominantly characterized by C–C and C–O bond cleavage in the repeating units, whereas LTA damage was primarily due to the cleavage of C–C bonds in the ring structure. In S. pneumoniae, damage to both WTA and LTA mainly occurred at the N-acetylglucosamine (GlcNAc) ring structure and the poly (RboP) site. This study offers new insights into the sterilizing effects of plasma.

The electronic and magnetic properties of lanthanide-doped GaN monolayers (Ln = La, Pr, Nd, Pm, Eu, and Gd) have been systematically investigated using density functional theory within the GGA-PBE approximation. Our results demonstrate that all Ln dopants except La introduce spin polarization and half-semiconductor behavior into the GaN monolayer. The observed magnetism primarily arises from unpaired 4f electrons, yielding magnetic moments of 2.0, 3.0, 4.0, 6.0, and 7.0 μ_B for Pr, Nd, Pm, Eu, and Gd, respectively. While La-, Pr-, and Gd-doped systems retain the indirect band gap characteristic of pristine GaN, an indirect-to-direct band gap transition occurs under biaxial tensile strains exceeding 2%. In contrast, Nd, Pm, and Eu doping directly induce a direct band gap without applied strain. Notably, under 6% tensile strain, the Pm- and Eu-GaN systems exhibit half-metallic and metallic properties, respectively. These tunable electronic and magnetic properties suggest that Ln doping offers a promising strategy for designing functional two-dimensional GaN-based electronic and spintronic devices.