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Time-resolved photoemission electron microscopy (PEEM) has established itself as a versatile experimental technique to unravel the ultrafast electron dynamics of materials with nanometer-scale resolution. However, the approach of performing PEEM-based, pixel-by-pixel lifetime mapping has not been reported thus far. Herein, we describe in detail the data pre-processing procedure and an algorithm to perform time-trace fittings of each pixel. We impose an energy cutoff for each pixel prior to spectral integration to enhance the robustness of our approach. With the energy cutoff, the energy-integrated time traces show improved statistics and lower fitting errors, thus resulting in a more accurate determination of the fit parameters, e.g., decay time constants. Our work allows us to reliably construct PEEM-based lifetime maps, which potentially shed light on the effects of local microenvironment on the ultrafast processes of the material and allow spatial distributions of lifetimes to be correlated with observables obtained from complementary microscopic techniques, hence enabling a more comprehensive characterization of the material. [ABSTRACT FROM AUTHOR]

Motivated by searching room-temperature superconductors that could be realized near ambient conditions, palladium hydrides were chosen as the research subject considering that they can stably exist under ambient conditions, and Li as an electron donor for its outstanding performance in chemically tuning stability. A novel cubic phase structure of Li2PdH6 with a remarkably high estimated Tc of ∼165 K at 90 GPa was found using particle swarm optimization algorithm calculations. The superconducting behavior persists down to 10 GPa with a high Tc of 106.382 K. Even though the parent binary Pd–H system is not a good superconductor, the introduction of extra electrons breaks up the H2 molecules, inducing the increase of atomic hydrogen compared with parent hydride, which is necessary for outstanding superconducting behavior. The existence of relatively soft phonons associated with the H atoms in phonon dispersion curves is responsible for its high-Tc. Our results indicated that the doping of Li to binary hydrides, especially to binary hydrides with low-Tc that exist under ambient pressure, can produce robust phonon-mediated superconductivity. This may be a strategy to design and optimize room-temperature superconductors that can be synthesized under modest pressure. The findings may pave the way for realizing new high-Tc superconductors in experiments under lower pressure than recently documented superconducting hydrides. [ABSTRACT FROM AUTHOR]

Low-cost and high-efficiency catalysts are of crucial importance for the electrocatalytic hydrogen evolution reaction (HER). Two-dimensional (2D) boron nitride (B–N) compounds formed by the combination of boron and nitrogen atoms of group III and V elements are promising candidates for electrocatalytic HER due to their significant electronic properties. Hence, an electrocatalyst is computer-aided designed with isolated single atoms of 3d, 4d, and 5d transition metals supported on 2D B–N (B2N, B5N3, and B7N5) monolayers to fabricate single-atom catalysts (SACs) with an excellent HER performance. Moreover, pH modulations are considered to improve the HER activity theoretically based on first-principles calculation. Our results indicate that B–N compounds surface doping with transition metal atoms can effectively enhance the HER catalytic performance over a wide range of pH. Among all SACs studied, Co-, Ti-, V-, Nb-, Ru-, Tc-, Zr-, and Os-embedded B2N, Sc-, Cr-, Mn-, Ti-, and Y-embedded B5N3, and Sc- and Mn-embedded B7N5 have excellent catalytic activity under acidic conditions, while Mo-, Ir-, Re-, Ta-, and W-embedded B2N and Ti- and Fe-embedded B7N5 show high catalytic activity under alkaline conditions. Interestingly, Hf@B2N and V@B5N3 systems exhibit promising catalytic activity under acidic, neutral, and alkaline conditions. Our work offers cost-effective candidates with a wide pH range HER performance for exploring ideal electrocatalysts. [ABSTRACT FROM AUTHOR]

Guiding and dynamically modulating topological defects are critical challenges in defect engineering of liquid crystals. Here, we employ molecular dynamics simulations to investigate the transition dynamics and relative kinetic stability of defect patterns in two-dimensional nematic Gay–Berne liquid crystals confined within rectangular geometries. We observe the formation of various defect patterns including long-axis, diagonal, X-shaped, composite, and bend configurations under different confinement conditions. The competition between boundary effects and the uniformity of nematic orientation induces the continuous realignment of liquid crystal molecules, facilitating the spatially continuous transformation of defect patterns over time. This transition involves changes in both defect types and their locations, typically initiating from defect regions. Furthermore, we demonstrate that the relative stability of these defect patterns can be effectively controlled by adjusting confinement parameters and external field conditions. Our findings provide fundamental insights into the transition kinetics of defect patterns in confined nematic liquid crystals, thereby enhancing our ability to manipulate topological defects for advanced applications. [ABSTRACT FROM AUTHOR]

Absolute line strength measurements of hydroperoxyl (HO2) radical in the OO-stretching (ν3) fundamental band have been performed by means of mid-infrared time-resolved dual-comb spectroscopy. By employing two sets of dual-comb spectrometers, high-resolution time-resolved spectra of HO2 and HCl, formed in the photolysis reaction system of Cl2/CH3OH/O2, could be, respectively, measured near 1123 and 3059 cm−1. With kinetic simulations, spectral analysis of both HO2 and HCl, as well as the accurate line strength of the HCl R(9) transition at 3059.316 cm−1, an absolute line strength of the ν3 131,13 ← 121,12 F1,2 transitions in HO2 at 1122.983 cm−1 was first determined to be 1.80 × 10−20 cm molecule−1 with a small uncertainty down to 4% under the conditions with low initial concentrations of Cl radical (1.63–1.81 × 1013 molecule cm−3). Furthermore, broadband high-resolution spectra of the ν3 fundamental band of HO2 were recorded in the range of 1088–1124 cm−1 with an average spectral resolution of 0.002 cm−1. By contour fitting the measured broadband spectra with PGOPHER, the line strengths of hundreds of rovibrational transitions were obtained relative to the well-determined HO2 lines at 1122.983 cm−1, and those values were observed to be higher than those tabulated in the HITRAN database by a factor of ∼2.8. Moreover, the absolute band strength of the ν3 fundamental band in HO2 was derived to be 22.3 km mol−1 with an uncertainty of 5%. This work providing precise and detailed spectral data would be crucial in revisiting the theoretical modeling of HO2 geometry and updating the database of the HO2 radical. [ABSTRACT FROM AUTHOR]

The generation of high-voltage ultrafast electrical pulses has significant potential for application in ultrawideband microwave sources, terahertz technology, and inertial confinement fusion. However, there is still a lack of the generation of high-voltage ultrafast electrical pulses with greater peak amplitudes and faster pulse widths and ultrafast characteristics. In this paper, a linear low-temperature gallium arsenide photoconductive semiconductor switch (LT-GaAs PCSS) is developed using the ps-scale carrier lifetime of low-temperature gallium arsenide (LT-GaAs). The generation of ultrafast electrical pulses with a pulse width of 0.5 ns and a voltage amplitude of 1 kV is achieved by triggering a pulsed laser with a wavelength of 1064 nm, a single pulse energy of 70 μJ, and a pulse width of 30 ps. The impact of parameters, such as bias electric field, laser pulse energy, and transmission line length, on the ultrafast characteristics of the output electric pulse of the LT-GaAs PCSS is investigated through a synthesis of experimental and simulation approaches. The results show that (1) in linear conditions, the output pulse amplitude is mainly determined by the bias voltage and laser pulse energy, and the output pulse amplitude is also affected by conductor and dielectric attenuation in the transmission line; (2) the falling edge is determined by the carrier lifetime. Because of the absorption depth at 1064 nm and the carrier lifetime of semi-insulating gallium arsenide material, the output electrical pulse has a trailing edge; (3) the bias voltage and laser pulse energy can improve voltage transmission efficiency, and the saturation of voltage transmission efficiency is caused by the saturation of photon absorption in LT-GaAs material. [ABSTRACT FROM AUTHOR]

In this work, the first fabrication and investigation of normally-off single crystal hydrogen-sterminated diamond MOSFETs with Ga2O3 dielectric has been successfully carried out. 50-nm-thick Ga2O3 was deposited by electron-beam evaporation technique at room temperature. The maximum drain current was −36 mA/mm, which was 164 times larger than previous work. Based on the transfer characteristic curve, the threshold voltage, on/off ratio and extrinsic transconductance were −0.37 V, 2.3 × 107, and 9.8 mS/mm, respectively. The effective mobility of the MOSFET was calculated to be 264.1 cm2/V ⋅s at VGS = − 1 V. This work may significantly promote the application of H-diamond FETs. [ABSTRACT FROM AUTHOR]

Intrinsic defects can have an effect on the microstructure of semiconductor materials, which can change the electronic structure of the material and ultimately alter its optical and magnetic properties. In this study, first-principles calculations are performed to demonstrate that the defect formation energies of VTe and ZnCd + VTe are lower under Cd-rich conditions. Conversely, under Te-rich conditions, with the exception of Tei, the defect formation energies for TeCd, VCd, ZnCd+ TeCd, and ZnCd+ VCd are lower, indicating that these defects exhibit greater stability within the system. Furthermore, it is demonstrated that VCd, CdTe, and TeCd introduce magnetic moments into the CdTe system, with VCd contributing the largest magnetic moment. Additionally, composite defects formed by ZnCd and VCd, CdTe, and TeCd also induce spin polarization and introduce magnetic moments. However, the synergistic effect of ZnCd on CdTe defects is significant, reducing the magnetic moment introduced by the CdTe defects. Moreover, ZnCd + VTe composite defects, VTe + VCd composite defects, and VTe, Cdi, and Tei do not introduce magnetic moments into the system. For the CdTe and ZnCd + CdTe defect systems, there is a notable impact on the optical properties, such as the refractive index and reflectance, compared to the perfect CdTe system. When CdTe defects are present, defect energy levels are introduced within the bandgap, affecting electronic transitions between energy bands, which, in turn, influences the magnetic and optical properties of the system. Additionally, it is found that the optical properties of CdTe systems containing intrinsic or composite defects are isotropic, exhibiting weak absorption in the visible light range. However, VTe and TeCd defects can enhance the absorption of visible light to some extent. [ABSTRACT FROM AUTHOR]

To broaden the bandwidth, a sandwich acoustic metamaterial with periodically rib-stiffened cores is presented by incorporating strip masses. The normal sound transmission loss of the structure is predicted using the finite element method. Results indicate that the two attenuation peaks are coupled, which is validated by the impedance tube experiment. The primary mechanism of the coupled-resonance is attributed to the continuous non-zero effective dynamic surface mass density between two anti-resonances. The conditions for generating the coupled-resonance are derived based on the dual mass-spring model without resolving the matrix eigenvalues. Numerical verifications suggest that the coupled band will break down into two isolated narrow bands if the conditions fail. [ABSTRACT FROM AUTHOR]

In view of the security problems of image encryption algorithms encoded by single DNA or RNA, to increase the randomness of the diffusion process and the uncertainty of the coding rules, we propose a combining dynamic RNA and DNA computing based chaotic image encryption algorithm, which has a more complicated encryption process for improving the security of the encryption algorithm and increases the difficulty of decoding. First, a new three-dimensional hyperchaotic map is proposed, which exhibits a rich set of dynamic behaviors. Second, the sequences generated by the proposed map are passed to NIST test with good randomness and implemented by digital signal processing hardware, which shows the feasibility of the proposed chaotic map for industrial applications. Second, the K-means algorithm is used to split the plaintext into two parts. Third, the chaotic sequence is used to displace and diffuse the two parts of the plaintext, respectively. Then, chaotic sequences were used to encode using dynamic DNA and RNA of these two parts, respectively. Then, the chaotic sequences were used to compute the dynamic DNA and RNA computing of these two parts, respectively. Finally, the cipher text is decoded accordingly. The experimental results show that compared with some related encryption algorithms, our method has higher security. [ABSTRACT FROM AUTHOR]

We investigate the vibrational ultrastrong coupling between molecular vibrations of water molecules and surface lattice resonances (SLRs) sustained by extended arrays of plasmonic microparticles. We design and fabricate an array of gold bowties, which sustain a very high field enhancement, with its SLR resonated with the OH stretching modes of water. We measure a Rabi splitting of 567 cm−1 in the strongly coupled system, whose coupling strength is 8% of the OH vibrational energy, at the onset of the ultrastrong coupling regime (10%). These results introduce metallic microparticle arrays as a platform for the investigation of ultrastrong coupling, which could be used in polaritonic chemistry to modify the dynamics of chemical reactions that require high coupling strengths. [ABSTRACT FROM AUTHOR]

Nozzle shape greatly affects the activity of cells and growth factors inside bio-ink, which is easy to be ignored. In this research, the finite element simulation software based on fluid dynamics theory was used to simulate the extrusion flow behavior of the bio-ink inside the printing needle. By establishing the flow models of two commonly used needles (cylindrical and conical needles), taking sodium alginate solution as bio-ink, the extrusion flow behavior of bio-ink inside the printing needle was simulated. Following, taking steady pressure, flow rate, and fluid shear stress as the research objectives, the response effects of nozzle geometry parameters, including shape, size, and feeding pressure, on the flow behavior of bio-ink were analyzed. Finally, a method based on the idea of integration for evaluating the cumulative damage to the active substances inside bio-ink has been proposed. Results show that the wall shear stress is the main stress suffered by bio-ink in the bio-printing process. Smaller inlet pressure and larger nozzle outlet diameter are beneficial for reducing wall shear stress. Compared with the cylindrical nozzle, although the maximum wall shear stress of the conical nozzle is higher than that of the cylindrical nozzle under the same inlet pressure and outlet nozzle diameter, the time of bio-ink subjected to the wall shear stress is shorter. The cumulative damage of the cylindrical nozzle is 29.65 Pa·s, and that of the conical nozzle is 18.25 Pa·s, which indicates that the conical nozzle has better biofriendliness and less damage to the active substance inside the bio-ink. [ABSTRACT FROM AUTHOR]

The CO reduction reaction (CORR) for the production of high-value-added multi-carbon (C2+) products is currently being actively investigated, where searching for high-efficiency catalysts with moderate CO intermediate binding strength and low kinetic barrier for C–C coupling poses a significant challenge. In this study, we employed density functional theory computations to design four synergistic coupling dual sites catalysts for CORR to C2 products, namely, TM-P@melon, by co-doping transition metals (TM = Mn, Fe, Co, and Ni) and phosphorus (P) into the polymeric carbon nitride (i.e., melon-CN). Mn–P@melon and Ni–P@melon exhibit higher selectivity toward C2H5OH and C2H6, respectively, with limiting potentials (C–C coupling kinetic energy barriers) of −0.43 V (0.52 eV) and −0.17 V (0.26 eV), respectively. The introduction of TM and P atoms not only narrows the band gap of melon-CN but also favors the coupling of CO and *CHO, providing an active site for C–C coupling, thus facilitating the catalytic reaction. Our work provides rational insights for the design of stable, low-cost, and efficient CORR dual sites catalysts that facilitate the sustainable production of high-value C2 chemicals and fuels. [ABSTRACT FROM AUTHOR]

Two-dimensional (2D) Sn-based perovskites exhibit significant potential in diverse optoelectronic applications, such as on-chip lasers and photodetectors. Yet, the underlying mechanism behind the frequently observed dual-peak emission in 2D Sn-based perovskites remains a subject of intense debate, and there is a lack of research on the carrier dynamics in these materials. In this study, we investigate these issues in a representative 2D Sn-based perovskite, namely, PEA2SnI4, through temperature-, excitation intensity-, angle-, and time-dependent photoluminescence studies. The results indicate that the high- and low-energy peaks originate from in-face and out-of-face dipole transitions, respectively. In addition, we observe an anomalous increase in the non-radiative recombination rate as temperature decreases. After ruling out enhanced electron–phonon coupling and Auger recombination as potential causes of the anomalous carrier dynamics, we propose that the significantly increased exciton binding energy (Eb) plays a decisive role. The increased Eb arises from enhanced electronic localization, a consequence of weakened lattice distortion at low temperatures, as confirmed by first-principles calculations and temperature-dependent x-ray diffraction measurements. These findings offer valuable insights into the electronic processes in the unique 2D Sn-based perovskites. [ABSTRACT FROM AUTHOR]

Based on the quantum valley Hall effect analogy, this work proposes a phononic crystal plate with ligament-type beams to obtain the topological valley transmission of elastic waves. A pure Bragg degenerate state appears in the high-frequency region with a resonator introduced. By rotating the central scatterer and the beams, the mirror symmetry is broken to form a topological bandgap. Subsequently, this work finds that two selective edge states also appear beside the commonly non-trivial crossing edge states in the topological bandgap by calculating the projected band and eigenvalue spectrum of the supercell with different valley Hall phases phononic crystals. Their appearance is due to band separation of the topological edge states caused by an increase in the rotation angle. Both selective edge states can transmit topologically in specific paths. They will help further to broaden the width of the frequency band of topological transmission. Besides, an elastic wave splitter is designed and demonstrated numerically, which can form two channels and three channels in different frequency bands. With the topological selective edge state disappearing, a topological corner state exists in the edge bandgap. This work provides a theoretical reference for practical applications of broadband elastic wave topological transmission and elastic energy trapping. [ABSTRACT FROM AUTHOR]

Liquid metal phase change materials have the advantages of high thermal conductivity and high volumetric latent heat, which are expected to address the growing challenges of thermal management of advanced electronics. In previous studies, the effect of radiative heat transfer from fins of a phase change heat sink on thermal management performance has rarely been considered. In this study, radiative coating materials with high emissivity were prepared and coated on the fins of the liquid metal phase change heat sink. The effect of radiative heat transfer on the performance of liquid metal phase change heat sink was investigated. The experimental results of continuous heating under natural convection conditions show that the introduction of the radiative coating with an emissivity of 0.9298 can extend the time for the surface temperature of the heat source to reach 100 °C by 9.4%, while shortening the recovery time of the phase change heat sink by 14.9%. The results of high-power cyclic heating indicate that the high emissivity coating can reduce the peak temperature by 16.6 °C in the tenth working cycle. A simplified numerical model was subsequently developed and validated to determine the specific effects of phase change and radiative heat transfer on the overall thermal control performance. The radiation-enhanced liquid metal phase change heat sink proposed in this study is simple and maintenance-free. It is expected to address the thermal management issues of electronic devices that cannot use active cooling or operate in thin-air environments. [ABSTRACT FROM AUTHOR]

This work presents a high-sensitivity solution sensor based on a phoxonic crystal nanobeam with lateral fins. The fins improve the stability of the suspended nanobeam and its detection performance is unaffected. Acoustic–optic dual-mode cross-detection improves the detection accuracy over the single-mode method. The acoustic and optical energies are concentrated in the defect and slot regions due to the combination of the gradient cavity and slot, which enhances the acoustic–optic interaction with the object to be measured, improving the detection sensitivity. Using the mode bandgaps of photonic and phononic crystals, the sensing characteristics are investigated using the finite element method. The impact of various concentrations on the transmission spectra of optical electromagnetic waves and acoustic elastic waves is investigated. The maximum sensitivity is 2149.5 kHz/ms−1, with Q of over 105 in the acoustic mode and 457.1 nm/RIU in the optical mode. The proposed nanobeam cavity with lateral fins can be used to realize miniaturized multi-mode acoustic–optic sensors. It also provides mechanical support, thermal transport, and channels for lateral carrier injection for the suspended nanobeam. [ABSTRACT FROM AUTHOR]

In this study, the excellent Y2−xNdxFe17 (x = 0, 0.2, 0.4, 0.6, 0.8) magnetic particles were prepared by the reduction–diffusion process. Through the ferromagnetic coupling between light rare earth element Nd and Fe atoms, we effectively modulated the magnetic crystallographic anisotropy of Y2Fe17. As the amount of Nd doping increases, the natural resonance frequency of Y2−xNdxFe17/PU increases to 15.7 GHz, the saturation magnetization increases to 120.43 emu/g, the Curie temperature increases to 390 K, and the average hyperfine field also increases to 22.5 T. Notably, the doping of Nd atoms leads to a slight expansion of the Y2−xNdxFe17 lattice, exhibiting distinct anisotropic characteristics that preferentially develop along the basal plane. The doping of rare earth Nd atoms with strong magnetic crystal anisotropy can not only significantly enhance the easy-plane magnetic crystallographic anisotropy, causing the natural resonance peak to shift toward higher frequencies, but also has important guiding significance for broadening the high-frequency application range of easy-plane rare earth transition metal alloys. This achievement provides new ideas and methods for the design and development of high-performance magnetic materials. [ABSTRACT FROM AUTHOR]

The interfacial local field is of critical importance in data analysis to deduce intrinsic surface responses from optical measurements of interfaces of condensed media but has not yet been well interrogated. We present here a simple approach to find local fields approximately at various interfaces of isotropic or nearly isotropic media. We divide a medium into atomic planes or molecular layers. It is found that the dipolar field contribution to the local field in a plane or layer from induced dipoles residing in planes beyond the nearest neighbor planes or layers is negligible; in many cases, the contribution is dominated by in-plane dipoles and the local field has a simple expression very much like that for an isotropic bulk. This finding allows us to calculate approximate local field variation at various interfaces. With the interfacial local field known, intrinsic surface response coefficients can be extracted from the optically measured surface responses. [ABSTRACT FROM AUTHOR]

The interaction between cavity photons and molecular vibrations leads to the formation of vibrational polaritons, which have demonstrated the ability to influence chemical reactivity and change material characteristics. Although ultrafast spectroscopy has been extensively applied to study vibrational polaritons, the nonlinear relationship between signal and quantum state population complicates the analysis of their kinetics. Here, we employ a second-order kinetic model and transform matrix method (TMM) to develop an effective model to capture the nonlinear relationship between the two-dimensional IR (or pump–probe) signal and excited state populations. We test this method on two types of kinetics: a sequential relaxation from the second to the first excited states of dark modes, and a Raman state relaxing into the first excited state. By globally fitting the simulated data, we demonstrate accurate extraction of relaxation rates and the ability to identify intermediate species by comparing the species spectra with theoretical ground truth, validating our method. This study demonstrates the efficacy of a second-order TMM approximation in capturing essential spectral features with up to 10% excited state population, simplifying global analysis and enabling straightforward extraction of kinetic parameters, thus empowering our methodology in understanding excited-state dynamics in polariton systems. [ABSTRACT FROM AUTHOR]

Carbonyl groups (C=O) play crucial roles in the photophysics and photochemistry of biological systems. O1s x-ray photoelectron spectroscopy allows for targeted investigation of the C=O group, and the coupling between C=O vibration and O1s ionization is reflected in the fine structures. To elucidate its characteristic vibronic features, systematic Franck–Condon simulations were conducted for six common biomolecules, including three purines (xanthine, caffeine, and hypoxanthine) and three pyrimidines (thymine, 5F-uracil, and uracil). The complexity of simulation for these biomolecules lies in accounting for temperature effects and potential tautomeric variations. We combined the time-dependent and time-independent methods to efficiently account for the temperature effects and to provide explicit assignments, respectively. For hypoxanthine, the tautomeric effect was considered by incorporating the Boltzmann population ratios of two tautomers. The simulations demonstrated good agreement with experimental spectra, enabling differentiation of two types of carbonyl oxygens with subtle local structural differences, positioned between two nitrogens (O1) or between one carbon and one nitrogen (O2). The analysis provided insights into the coupling between C=O vibration and O1s ionization, consistently showing an elongation of the C=O bond length (by 0.08–0.09 Å) upon O1s ionization. [ABSTRACT FROM AUTHOR]

Surface functionalization of low-dimensional nanomaterials offers a means to tailor their optoelectronic and chemical characteristics. However, functionalization reactions are sensitive to the inherent surface features of nanomaterials, such as defects, grain boundaries, and edges. Conventional optical characterization methods, such as Raman spectroscopy, have limited sensitivity and spatial resolution and, therefore, struggle to visualize reaction sites and chemical species. Here, we demonstrate the capability of spatially and chemically sensitive tip-enhanced Raman spectroscopy imaging to map the distribution of molecules in covalently functionalized graphene. Hyperspectral vertex component analysis and density functional theory are necessary to interpret the nature of binding sites and extract information from the spatially and spectrally heterogeneous datasets. Our results clarify the origin of heterogeneous surface functionalization, resolving preferential binding at edges and defects. This work demonstrates the potential of nanospectroscopic tools combined with unsupervised learning to characterize complex, partially ordered optoelectronic nanomaterials. [ABSTRACT FROM AUTHOR]

Large Schottky barriers formed at the interfaces between graphene and 2D semiconductors often degrade device performance. Here, taking the Janus MoSO as a prototype and using the first-principles calculations together with the band unfolding technique, we demonstrate that the Ohmic contact (OC), which is absent in pristine graphene/MoXY (X/Y = S, Se, Te. X ≠ Y), is realized in the pristine graphene/MoSO (G/MoSO) heterostructure. G/OMoS shows the n -type OC (OC- n) that leads to the p -doping of the graphene layer with a hole density of 1.17 × 10 13 /cm 2 , while G/SMoO exhibits the p -type Schottky contact with a tunable Schottky barrier height. The realization of OC and the interface dependent contact type are mainly attributed to the large intrinsic dipole between asymmetric S and O layers, which dominate the different behaviors of charge transfer and the associated interface dipole in heterostructures. Inspired by the finding, considering the larger dipole moment in Janus MoSeO and MoTeO, we further confirm that both OC- n and OC- p exist in pristine G/MoSeO and G/MoTeO. Moreover, on comparison with MoSO, both G/OMoS and G/SMoO show enhanced optical absorptions (∼ 10 5 cm − 1 ) in most of the visible light range. Our results not only show the potential application of G/MoSO in nanoelectronic devices such as field-effect transistors but also indicate that dipole engineering would help us to predict or design desirable electric contacts of Janus-transition metal dichalcogenide-based metal/semiconductor systems in advance. [ABSTRACT FROM AUTHOR]

This work reports heavy ion-irradiation effects in polycrystalline Fe3O4. For this matter, Fe/Fe3O4 heterostructures were irradiated in situ in a transmission electron microscopy with 1 MeV Kr ions at 50 K. Evidence of cubic to monoclinic transformation (a.k.a Verwey transition) was recorded in some magnetite grains upon cooling the sample (around 90 K); however, most of the oxide grains retain their cubic spinel structure. Irradiation effects were analyzed in the cubic phase up to a maximum dose of 38 dpa without the sign of amorphization. The extinction of first-order reflections was recorded at doses below 1 dpa, indicating the formation of a new (metastable) phase with half of the lattice parameters compared to the unirradiated Fe3O4 crystal. The formation of the new crystalline phase, which also presents a high resistance to amorphization, is related to the disordering of the cation lattice and the high mobility of the cation interstitials. The metastable phase readily recovers around 225 K during the natural warming of the sample from 50 K to room temperature. [ABSTRACT FROM AUTHOR]

The cytoskeleton, a dynamic network of structural proteins within cells, is essential for cellular deformation and responds to external mechanical cues. Here, based on the structure of the cytoskeleton, combined with the biochemical reactions of the activator RhoA and the inhibitor F-actin, we develop a novel mechanochemical cytoskeleton model to investigate the mechanical behavior of cells. Interestingly, we find that active stress fibers exhibit diverse dynamical modes at specific inhibitor concentration thresholds. The existence of concentration differences and sustained mechanochemical feedback in activators and inhibitors trigger a global oscillation of isolated cells. In addition, under uniaxial and biaxial stretches, activators and inhibitors preferentially diffuse toward the more significantly deformed cytoskeletal elements, and their dynamic interactions regulate the cell to align with the main stretching direction. Our findings, consistent with many experimental results, provide fundamental insights into cytoskeletal remodeling and cellular mechanosensing mechanisms. [ABSTRACT FROM AUTHOR]

The ferroelectric tunneling junctions (FTJs) are widely recognized as one of the non-volatile memories with significant potential. Ferroelectricity usually fades away as materials are thinned down below a critical value, and this problem is particularly acute in the case of shrinking device sizes, thus attracting attention to two-dimensional ferroelectric materials (2DFEMs). In this work, we designed 2D ferroelectric Ga2O3-based FTJs with out-of-plane polarization, and the influence of metal–semiconductor contact in the electrode region on the system is considered. Here, using density functional theory combined with the non-equilibrium Green's function approach to quantum transport calculations, we demonstrate robust ferroelectric polarization-controlled switching behavior between metallic and semiconducting states in Ga2O3/WS2 ferroelectric heterostructures. The potential barrier of the metal–semiconductor contact in the electrode region is lower than that of the intrinsic material, thereby resulting in an increased probability of electron tunneling. Our results reveal the crucial role of 2DFEMs in the construction of FTJs and highlight the significant impact of electrode contact types on performance. This provides a promising approach for developing high-density ferroelectric memories based on 2D ferroelectric semiconductor heterostructures. [ABSTRACT FROM AUTHOR]

Magnetic gels with embedded micro-/nano-sized magnetic particles in cross-linked polymer networks can be actuated by external magnetic fields, with changes in their internal microscopic structures and macroscopic mechanical properties. We investigate the responses of such magnetic gels to an external magnetic field, by means of coarse-grained molecular dynamics simulations. We find that the dynamics of magnetic particles are determined by the interplay of magnetic dipole–dipole interactions, polymer elasticity, and thermal fluctuations. The corresponding microscopic structures formed by the magnetic particles, such as elongated chains, can be controlled by the external magnetic field. Furthermore, the magnetic gels can exhibit reinforced macroscopic mechanical properties, where the elastic modulus increases algebraically with the magnetic moments of the particles in the form of ∝ (m − m c ) 2 when magnetic chains are formed. This simulation work can not only serve as a tool for studying the microscopic and the macroscopic responses of the magnetic gels, but also facilitate future fabrications and practical controls of magnetic composites with desired physical properties. [ABSTRACT FROM AUTHOR]

In this numerical study, we propose dual-modulated topological pillared phononic crystal (PnC) plates and demonstrate their application in achieving frequency-selective waveguiding of Lamb-wave valley-edge states. We show that both the radius and the height of the pillars in the honeycomb unit cell can be varied, allowing a generalized parameter space to obtain the complete topological bandgaps and two groups of distinct valley Hall phases for designing topological waveguides operating in different frequency ranges. Accordingly, we construct different types of phase domain walls to support valley-edge states using the dual-modulated PnC plates with a lattice constant of 2000 μm and with topological bandgaps opened around the Dirac cone frequency of 426 kHz. The numerical results show that the valley-edge states emerge to cover different frequency ranges and exhibit robust backscattering immunity when propagating along zigzag paths with sharp corners. Furthermore, the transport path of the valley-edge states can be designed to be highly dependent on the operating frequency in different domain walls. Consequently, we design a straight waveguide and three multichannel waveguides to demonstrate frequency-dependent switchable transmission and selective channeling of valley-edge states, respectively. The results of this study pave the way for the development and optimization of topological acoustic circuits using the generalized parameter space approaches and are expected to find promising applications in frequency-controlled and signal-division devices. [ABSTRACT FROM AUTHOR]

PN junctions play important roles in semiconductor devices. Flexoelectricity, an electromechanical coupling between strain gradient and electric polarization, has non-negligible contributions in nano-devices. The thermoflexoelectric effect is a phenomenon in which temperature gradients generate inhomogeneous strains and further induce flexoelectric polarizations. Therefore, temperature gradients can affect carrier transport in PN junctions through the thermoflexoelectric effect. In this paper, a one-dimensional model of the PN junction under a uniform temperature change is established. Exact solutions for the electromechanical fields in the PN junction are obtained for the first time. The effects of the temperature gradient, doping level, and flexoelectric coefficient on the electromechanical behaviors of the PN junction are numerically analyzed. The results indicate that carrier concentrations in the p and n regions are sensitive to temperature gradients because of the screening effect of the mobile charge on the flexoelectric polarization induced by the temperature gradient. Meanwhile, the flexoelectric field and the initial built-in electric field in the depletion region jointly determine the magnitude of the potential barrier, and thus, the temperature-gradient-induced flexoelectric field can tune the switching characteristics of the PN junction. This study provides a theoretical basis for the tuning of the electromechanical behavior of the PN junction by thermally induced flexoelectric fields. [ABSTRACT FROM AUTHOR]

We introduce a novel water bath hydrogenation process designed to enhance the magnetic properties and hyperfine field of Y2Fe17. The core of this process lies in the successful preparation of a new compound Y2Fe17H3.5 by introducing hydrogen in a mild water bath environment, accomplished by a chemical reaction between calcium, Y2Fe17, and ammonium acetate solution at room temperature and pressure. After hydrogen doping, cell volume expansion increased from 778.511 to 795.383 Å3, and notably, lattice expansion is anisotropic. Furthermore, saturation magnetization is increased from 103 to 134.93 emu/g, Curie temperature is increased from 320 to 461 K, and the average hyperfine field is increased from 18 to 25 T. The improvement in magnetic properties is due to the increase in Fe–Fe distance, which according to the Bethe–Slater curve leads to stronger Fe–Fe exchange interactions and enhancing ferromagnetic interactions. This work not only proposes the novel rhombohedral Y2Fe17H3.5 with excellent magnetic properties, but also provides a new method for hydrogen doping in Y2Fe17 which lays the foundation of fundamental solid state physics for further research. [ABSTRACT FROM AUTHOR]

In this manuscript, carrier transport simulation methods are proposed for devices with the coexistence of quantum transport and diffusive transport by combining the nonequilibrium Green's function method with the drift-diffusion transport simulation method. Current continuity between quantum transport and drift-diffusion transport is ensured by setting quantum transport current as the connection boundary condition of drift-diffusion simulation or by introducing quantum transport-induced carrier generation rates to drift-diffusion simulation. A comprehensive study of our method and the method combining the Wentzel–Kramers–Brillouin (WKB) method with the drift-diffusion transport simulation method is performed for n-type tunnel oxide passivating contact solar cell to investigate their applicable conditions and balance the accuracy and computational cost. As the oxide barrier width, barrier height, and electron effective mass increase, or the doping concentration in the electron transport layer decreases to the extent that the blocking effect of the oxide barrier on light-generated electrons becomes significant, method I is more accurate since the transmission coefficient near the conduction band edge calculated by WKB is overestimated; otherwise, method II is more suitable due to its low computational cost without the loss of accuracy. In addition, the differences between current densities, carrier densities, and Shockley–Read–Hall recombination rates simulated under the two current continuity conditions for the solar cell with different carrier mobilities are also further explored and analyzed. [ABSTRACT FROM AUTHOR]

Standing striations with a unique pattern have been observed in a radio-frequency-generated hydrogen plasma. The striation pattern consists of a sequence of closely spaced bright ring doublets and two types of dark gaps of different widths. The bright and dark regions in striations were spectroscopically resolved with the Balmer series and the Fulcher band emission lines of hydrogen. Temperatures in these fine structures were determined. In general, the wider dark gap has a higher excitation temperature than the nearby narrower ones in the striation pattern sequence. Bright regions are rotationally hotter than the adjacent dark ones. However, for vibrational temperatures, the trends are not so obvious. No clear pressure dependence of temperatures was observed in striations within the pressure range of maintaining stable standing striations in this work. In addition to optical emission spectroscopy, we used graphite granules as in situ probes for plasma conditions in different striation regions. The striated hydrogen plasma-treated graphite granules were analyzed with Raman spectroscopy. The observed hydrogen-graphite interaction was correlated with the measured temperatures and the fine structures of striations in a discharge tube. [ABSTRACT FROM AUTHOR]

Alternating current (AC) loss measurement is crucial for the theoretical evaluation and optimization in the fabrication of superconducting AC devices. Lock-in amplifier based on the lock-in phase is commonly adopted and inevitably involves with phase error. In this work, a novel approach for measuring transport AC loss by determining the minimum compensated voltage (MCV) was developed, in which the lock-in amplifier was removed. Since it just uses the voltage signal from an AC voltmeter, it is phase-error immune. Experimental results demonstrated that when using the lock-in amplifier, there existed a system error as the initial phase difference between the sampled (reference) and real current phases, which required careful compensation. In contrast, the phase error no longer needed to be considered by the MCV method, and the AC loss results were obtained much more conveniently with the relative error between the theoretical and the experimental of less than 5%. Finally, the AC loss of a coated conductor spiral wound on an epoxy bar was obtained using the presented approach, demonstrating its low cost, ease of operation, and high accuracy. [ABSTRACT FROM AUTHOR]

Glass transition, commonly manifested upon cooling a liquid, is continuous and cooling rate dependent. For decades, the thermodynamic basis in liquid–glass transition has been at the center of debate. Here, long-time isothermal annealing was conducted via molecular dynamics simulations for metallic glasses to explore the connection of physical aging in supercooled liquid and glassy states. An anomalous two-step aging is observed in various metallic glasses, exhibiting features of supercooled liquid dynamics in the first step and glassy dynamics in the second step, respectively. Furthermore, the transition potential energy is independent of initial states, proving that it is intrinsic for a metallic glass at a given temperature. We propose that the observed dynamic transition from supercooled liquid dynamics to glassy dynamics could be glass transition manifested isothermally. On this basis, glass transition is no longer cooling rate dependent, but is shown as a clear phase boundary in the temperature-energy phase diagram. Hence, a modified out-of-equilibrium phase diagram is proposed, providing new insights into the nature of glass transition. [ABSTRACT FROM AUTHOR]

Lithium niobate ( LiNbO 3 , LN) on insulator (LNOI) has emerged as a promising platform for integrated photonics, due to the strong optical confinement and excellent nonlinear optical and electrical characteristics of LN crystal. Focused ion beam (FIB) as a versatile technique has become a typical way to fabricate LNOI microstructures. However, due to the bombardment of Ga + ions during fabrication, the LN lattice is damaged, which would deteriorate the performance of LNOI devices. Thus, the recognition of the damage formed by FIB fabrication is necessary for the control and optimization of the properties of LN microstructures. However, previous studies on this issue have not delved into it from a lattice perspective. Here, we conducted an investigation into the damage inflicted on LN film due to FIB fabrication and the subsequent impact of buffered oxide etching (BOE) treatment on this damage using Raman spectroscopy. Our findings indicate that the interaction between Ga + ions and LN film results in lattice amorphization, as well as a reduction in the ionic bonding and lattice stress within LN. Furthermore, absorption spectra were acquired both before and after BOE treatment, revealing the emergence of additional optical losses attributed to Ga + ions. Notably, these defects responsible for optical losses are predominantly concentrated near the surface of the milled LN film, and BOE treatment proves efficient in their removal. This study contributes to further understanding of the defect structure in LN film after FIB fabrication, as well as repairing the damage and, thus, improving the performance of LN microstructures. [ABSTRACT FROM AUTHOR]

Precise positioning of single site-controlled inverted pyramidal InGaAs quantum dots (QDs) at the antinode of a GaAs photonic crystal cavity with nanometer-scale accuracy holds unique advantages compared to self-assembled QDs and offers great promise for practical on-chip photonic quantum information processing. However, the strong coupling regime in this geometry has not yet been achieved due to the low cavity Q-factor based on the (111)B-oriented membrane structures. Here, we reveal the onset of phonon-mediated coherent exciton–photon interaction on our tailored single site-controlled InGaAs QD–photonic crystal cavity. Our results present the Rabi-like oscillation of luminescence intensity between excitonic and photonic components correlated with their energy splitting pronounced at small detuning. Such Rabi-like oscillation is well reproduced by modeling the coherent exchange of the exciton-photon population. The modeling further reveals an oscillatory two-time covariance at QD-cavity resonance, which indicates that the system operates at the onset of the strong coupling regime. Moreover, by using the cavity mode as a probe of the virtual state of the QD induced by phonon scattering, it reveals an increase in phonon scattering rates near the QD–cavity resonance and asymmetric phonon emission and absorption rate of even around 50 K. [ABSTRACT FROM AUTHOR]

The homeotic transformation of stamens into pistil-like structures (pistillody) causes cytoplasmic male sterility (CMS). This phenomenon is widely present in plants, and might be induced by intracellular communication (mitochondrial retrograde signaling), but its systemic regulating mechanism is still unclear. In this study, morphological observation showed that the stamens transformed into pistil-like structures, leading to flat and dehiscent pistils, and fruit set decrease in sua-CMS (MS K326, somatic fusion between Nicotiana. tabacum L. K326 and Nicotiana suaveolens). Transcriptome data analysis presented that the expression levels of B-class MADS genes, including pMADS1, GLO1, GLO2, pMADS2.1, pMADS2.2, significantly reduced in the pistil-like structure of sua-CMS. DEGs were enriched in flavonoid and phenylpropanoid biosynthesis pathways. Transcriptome and metabolomics analysis revealed that the expression levels of CHI/CHS (key enzymes regulating flavonoid synthesis), and the contents of flavonoids reduced significantly in the pistil-like structures of sua-CMS. Chemical fluorescence staining assay showed that reactive oxygen species (ROS) levels were higher in the pistil-like structure of sua-CMS. Application of external flavonoids (hesperetin) reduced the frequency of pistillody and ROS levels. These results suggested that the metabolism of flavonoids played important roles in regulating pistillody through ROS in sua-CMS. Our study provides new insights into the regulatory mechanism of pistillody in plants. [ABSTRACT FROM AUTHOR]

This paper is devoted to proving the small noise asymptotic behavior, particularly large deviation principle, for multi-scale stochastic dynamical systems with fully local monotone coefficients driven by multiplicative noise. The main techniques rely on the weak convergence approach, the theory of pseudo-monotone operators and the time discretization scheme. The main results derived in this paper have broad applications to various multi-scale models, where the slow component could be such as stochastic porous medium equations, stochastic Cahn-Hilliard equations and stochastic 2D Liquid crystal equations. [ABSTRACT FROM AUTHOR]

A catalyst (ZIS/Ag@CN) with the ultra-close Van der Waals contact and silver single-atom bridge has been designed for photocatalytic water splitting. [Display omitted] The construction of ultra-close 2D atomic-thickness Van der Waals heterojunctions with high-speed charge transfer still faces challenges. Here, we synthesized single-layer ZnIn 2 S 4 and g-C 3 N 4 , and introduced silver single atoms to regulate Van der Waals heterojunctions at the atomic level to optimize charge transfer and catalytic activity. At the atomic scale, the impact of detailed structural differences between the two characteristic surfaces of ZnIn 2 S 4 ([Zn-S 4 ] and [In-S 4 ]) on catalytic performance has been first proposed. Experiments combined with the DFT study demonstrate that single atom Ag not only acts as a charge transfer bridge but also regulates the energy band and intrinsic catalytic activity. Benefiting from the enhanced electron delocalization, the synthesized catalyst ZIS/Ag@CN exhibits excellent photocatalytic performance, with a hydrogen production rate of 5.50 mmol·g−1·h−1, which is much higher than the reported Ag-based single-atom catalysts so far. This work provides a new understanding of atomic-level heterojunction interface regulation and modification. [ABSTRACT FROM AUTHOR]

[Display omitted] • Mitochondrial dysfunctions associated with ageing contributes to neurodegenerative diseases. • Mushrooms have been highlighted as one of the natural products that contain antioxidants. • Ergothioneine-rich L.edodes mushroom is a potential neuroprotective agent that restores mitochondrial functions. A decline in mitochondrial functions associated with ageing is the key factor of free radical generation which contributes to age-related pathologies. Protecting healthy functional mitochondrial networks with antioxidants is critical in promoting healthy ageing. This study aimed to investigate the protective effect of ergothioneine (EGT)-rich Lentinula edodes extract (LE-ETH) against tert -butyl hydroperoxide (t-BHP) assaulted senescent HT22 cells. Mitochondrial function was evaluated by measuring mitochondrial membrane potential (MMP), ATP levels and mitochondrial toxicity. The protective mechanisms were elucidated via the exploration of antioxidant and mitochondrial biogenesis signalling pathways. Our results revealed that a low dose of t-BHP increases mitochondrial toxicity. The pretreatment with 100 µg/mL of LE-ETH and the equimolar concentration of EGT for 8 h significantly improve the mitochondrial function and reduced inflammation. Through gene expression studies, we demonstrated that pretreatment of LE-ETH significantly improves the antioxidant and mitochondrial biogenesis pathway via Nrf2 signaling axis. However, the downstream genes of the mitochondrial biogenesis pathway were unaffected by equimolar EGT concentration. Gas chromatography-mass spectrum (GC–MS) analysis was carried out to identify the bioactive compounds that are present in LE-ETH extract which contributed to its efficacy in improving the mitochondrial functions. A total of 23 compounds consisting of phenols, fatty acids, and sterols were identified in the ethanolic extract. Pentanoic acid was the major compound identified in LE-ETH. These findings demonstrated that EGT-rich L.edodes mushroom is a potential neuroprotective agent which could serve as a potential therapeutic strategy for the preservation of mitochondrial functions in healthy ageing explorations. [ABSTRACT FROM AUTHOR]

This study investigates the effects of electric current on cathode contact resistance in solid oxide fuel cell stacks. La 0.8 Sr 0.2 MnO 3 (LSM) and La 0.6 Sr 0.4 CoO 3 (LSC) tapes of ∼100 μm thickness are adopted as cathode contact layers. The tapes are sandwiched between sintered LSM or LSC cathode wafers and Fe–Cr alloy coupons coated with protective LSM or Mn 1.5 Co 1.5 O 4 films to simulate the structure in the stacks. Electric resistance is measured at 700 °C for 1000 h with and without continuous current passage during measurement. The samples with current passage exhibit faster resistance rising rates than the no-current ones. Microstructural examinations reveal gaps existing at both the coating/contact tape and the cathode/contact tape interfaces, which should be responsible for the major part of resistance increase. It is supposed that continuous current passage causes Joule heating and local gap formation at contact interfaces, depending on the coefficients of thermal expansion and resistivity of contact components. The sample consisting of LSM coating/LSM contact tape/LSM cathode shows a highest resistance increasing rate. • Electric current passage causes Joule heating in cathode contact materials. • Joule heating induces thermal stress and delamination at contact interfaces. • Interface delamination correlates with resistivity and expansion of contact materials. • Contact resistance increases mainly due to gap formation at contact interfaces. [ABSTRACT FROM AUTHOR]

Highway guardrails are critical safety infrastructure along roadways, designed to redirect vehicles back into their lanes and facilitate a gradual deceleration to a complete stop. Traditional highway steel guardrails exhibit significant limitations, including inadequate energy absorption, susceptibility to corrosion, and an increased risk of vehicles leaving the roadway during severe collisions. Furthermore, the production and transportation of these guardrails contribute to substantial carbon emissions and environmental pollution. This study presents an optimization of the cross-sectional shape of the conventional corrugated beam guardrail, proposing a lightweight structure that incorporates high yield strength steel plate HR700F to enhance energy absorption capacity. The safety performance of the proposed guardrail is rigorously assessed through finite element numerical simulations and full-scale collision tests with real vehicles. Key performance indicators—such as the maximum dynamic lateral deflection of the guardrail, occupant impact velocity, and acceleration—are utilized to evaluate the energy absorption and protective efficacy of the structure. Results indicate that the optimized guardrail not only meets SB-level safety standards but also demonstrates superior anti-collision performance and effective energy absorption and buffering characteristics. The proposed design achieves a reduction in beam plate thickness by 1.3 mm, resulting in a lightweight structure with a weight reduction of up to 44%, thereby supporting the advancement of low-carbon, environmentally sustainable transportation solutions. [ABSTRACT FROM AUTHOR]

The Cox-Maze IV (CMIV) procedure is the mainstay in surgical treatment of atrial fibrillation (AF), but the rate of AF recurrence after the CMIV procedure in patients with persistent AF is difficult to accurately evaluate. In this study, we aimed to develop and validate a risk prediction model of AF recurrence within 1 year after undergoing the Cox-Maze IV procedure. We retrospectively enrolled 303 consecutive patients who underwent the Cox-Maze IV procedure for persistent AF concomitant with other cardiac procedures at our institute between 2019 and 2021. A nomogram was developed using multivariate logistic regression analysis, and the concordance statistic (C-statistic) was computed. Differentiation, calibration, clinical suitability, and bootstrapping were performed to verify the model. Among the 303 patients, 71 developed recurrent AF within 1 year of CMIV. Factors predictive of postoperative AF recurrence included age, left ventricular hypertrophy (LVH), early atrial tachyarrhythmias (ATAs), and congenital heart disease surgery (namely, ventricular septal defect repair and atrial septal defect repair). Based on the training dataset, the nomogram had a C-statistic of 0.864 (95% CI 0.811–0.918) for predicting AF recurrence. According to the receiver operating characteristic curve, (ROC curve), the cutoff value of the model was 0.293, and the specificity and sensitivity were 0.841 and 0.789, respectively. This model can predict the risk of AF recurrence after the CMIV procedure. Its discrimination, calibration, and clinical applicability are strong, and its clinical application is simple and easy to promote. [ABSTRACT FROM AUTHOR]

AbstractThe most common type of proximal humerus fracture is surgical neck fracture. The purpose of this paper is to study the mechanical mechanism and the effect of bone degeneration on humeral surgical neck fractures. The right humerus finite element models were established based on CT computed tomography. The stress values and crack propagation process under an axial force were obtained. Three indexes (mechanical property, cortical bone thickness of diaphysis and cancellous bone volume fraction) in this article were used to describe bone degeneration. The results showed that the three models group with different index had the same conclusions. The calculation results showed that the higher the bone degeneration level, the shorter the fracture time and the lower the fracture stress. The crack initiated from the medial side of the humerus, then gradually grew toward lateral side along the both sides, and finally broke. The medial crack was flat and single like "a thin line", while the lateral fracture of the humerus was irregular and crushed into fragments. The medial humerus cracks were generated by tensile stress, while the lateral cracks were generated by compressive stress. The thickness of humerus diaphysis might be used as the index of fracture risk due to direct readability from clinical images and quantitative relation of fracture risk. This article would provide reference data for the treatment and prevention of humeral surgical neck fracture. [ABSTRACT FROM AUTHOR]

A series of LiY 0.98- y Re y (MoO 4) 2 :0.02Sm3+ (Re = Gd, La) phosphors were synthesized via a high-temperature solid-phase reaction. The purity of the powder phase, crystal structure, morphology, elemental composition, luminescent properties, thermal stability, and electroluminescence of the phosphors were comprehensively analyzed. The photoluminescence spectrum obtained under excitation at 404 nm shows four strong emissions caused by the 4f-4f transition of Sm3+ ions. By partially substituting Y3+ ions with La3+ and Gd3+ ions, the photoluminescence intensity of the LiY 0.98 (MoO 4) 2 :0.02Sm3+ samples is significantly enhanced. The electroluminescence spectra of the LED devices fabricated using commercial 405 nm LED chips and LiY 0.88 Gd 0.10 (MoO 4) 2 :0.02Sm3+ or LiY 0.88 La 0.10 (MoO 4) 2 :0.02Sm3+ phosphors overlap with the absorption bands of the P R phytochrome state, indicating their potential application in plant growth lamps. [ABSTRACT FROM AUTHOR]

Detecting ascorbate imbalances is crucial for timely disease diagnosis and sample monitoring across various conditions. In this study, we synthesized N,S-GQDs and employed the fluorescence quenching effect of CoOOH nanosheets through resonance energy transfer (FRET) to visually detect changes in ascorbate levels. Upon the addition of ascorbic acid (AA), the reduction reaction with CoOOH induced fluorescence recovery in N,S-GQDs. Our findings demonstrate that the synthesized N,S-GQDs/CoOOH nanocomplexes provide a reliable probe for fluorescence-based detection of ascorbic acid within a linear range of 2–82 μM, with a detection limit of 48.3 nM. Additionally, quantitative determination of ascorbic acid in blood and orange juice samples was successfully achieved using the N,S-GQDs/CoOOH, with good recovery rates. Importantly, confocal fluorescence imaging experiments conducted on MCF-7 cells and zebrafish confirmed that the synthetic N,S-GQDs/CoOOH can effectively visualize the overexpression of ascorbic acid in vivo. [ABSTRACT FROM AUTHOR]

Background: As China's "Internet + Health" initiative advances, the digital economy significantly influences the quality of medical and health services. However, there is a research gap concerning the digital economy's specific impacts, mechanisms, and marginal effects on these services. This gap impedes a comprehensive understanding of the digital economy's potential in healthcare. Aims: This study aims to clarify the digital economy's impact mechanisms on medical and health services levels, offering a scientific foundation for more targeted and effective policy formulation, thereby fostering sustainable digital development in healthcare. Methods: Utilizing panel data from China's 31 provinces (2011–2020), this paper employs the Spatial Durbin Model to analyze the spatial and marginal effects of the digital economy on healthcare service levels. To ensure analysis accuracy and robustness, the study refines the spatial weight matrix and addresses model endogeneity using the Generalized Spatial Two-Stage Least Squares method. Additionally, it examines regional disparities in the digital economy's impact through SDM and explores intermediary mechanisms and threshold effects using a mediation effect model and a panel threshold model. Results: Findings indicate that the digital economy positively affects medical and health services in both local and neighboring regions, with variations across areas. The eastern region particularly benefits from the digital economy's enhancement of service levels, while the central and western regions see less impact. The digital economy enhances services by improving medical resource levels and promoting their coordinated development. However, this positive effect is moderated by the digital economy's and the region's economic development levels, with more pronounced impacts in regions with higher digital and economic development. Conclusions: The digital economy plays a crucial role in improving medical and health services, and its full potential is beneficial for the industry's advancement and sustainability. Nonetheless, addressing the uneven digital economy development across regions is essential to ensure equitable benefits for all areas. [ABSTRACT FROM AUTHOR]

Persistent topological Laplacians constitute a new class of tools in topological data analysis (TDA). They are motivated by the necessity to address challenges encountered in persistent homology when handling complex data. These Laplacians combine multiscale analysis with topological techniques to characterize the topological and geometrical features of functions and data. Their kernels fully retrieve the topological invariants of corresponding persistent homology, while their non-harmonic spectra provide supplementary information. Persistent topological Laplacians have demonstrated superior performance over persistent homology in the analysis of large-scale protein engineering datasets. In this survey, we offer a pedagogical review of persistent topological Laplacians formulated in various mathematical settings, including simplicial complexes, path complexes, flag complexes, digraphs, hypergraphs, hyperdigraphs, cellular sheaves, and N-chain complexes. [ABSTRACT FROM AUTHOR]

This study investigates the grain morphology, microstructure, magnetic properties and shape memory properties of an Fe41.265Ni28.2Co17Al11Ta2.5B0.04 (at%) high-entropy alloy (HEA) cold-rolled to 98%. The EBSD results show that the texture intensities of the samples annealed at 1300 °C for 0.5 or 1 h are 2.45 and 2.82, respectively. This indicates that both samples were formed without any strong texture. The grain morphology results show that the grain size increased from 356.8 to 504.6 μm when the annealing time was increased from 0.5 to 1 h. The large grain size improved the recoverable strain due to a reduction in the grain constraint. As a result, annealing was carried out at 1300 °C/1 h for the remainder of the study. The hardness decreased at 24 h, then increased again at 48 h; this phenomenon was related to the austenite finish temperature. Thermo-magnetic analysis revealed that the austenite finish temperature increased when the samples were aged at 600 °C for between 12 and 24 h. When the aging time was prolonged to 48 h, the austenite finish temperature value decreased. X-ray diffraction (XRD) demonstrated that the peak of the precipitates emerged and intensified when the aging time was increased from 12 to 24 h at 600 °C. From the three-point bending shape memory test, the samples aged at 600 °C for 12 and 24 h had maximum recoverable strains of 2% and 3.6%, respectively. The stress–temperature slopes of the austenite finish temperature were 10.3 MPa/°C for 12 h and 6 MPa/°C for 24 h, respectively. Higher slope values correspond to lower recoverable strains. [ABSTRACT FROM AUTHOR]

Video instance segmentation, a key technology for intelligent sensing in visual perception, plays a key role in automated surveillance, robotics, and smart cities. These scenarios rely on real-time and efficient target-tracking capabilities for accurate perception and intelligent analysis of dynamic environments. However, traditional video instance segmentation methods face complex models, high computational overheads, and slow segmentation speeds in time-series feature extraction, especially in resource-constrained environments. To address these challenges, a Dual-Channel and Frequency-Aware Approach for Lightweight Video Instance Segmentation (DCFA-LVIS) is proposed in this paper. In feature extraction, a DCEResNet backbone network structure based on a dual-channel feature enhancement mechanism is designed to improve the model's accuracy by enhancing the feature extraction and representation capabilities. In instance tracking, a dual-frequency perceptual enhancement network structure is constructed, which uses an independent instance query mechanism to capture temporal information and combines with a frequency-aware attention mechanism to capture instance features on different attention layers of high and low frequencies, respectively, to effectively reduce the complexity of the model, decrease the number of parameters, and improve the segmentation efficiency. Experiments show that the model proposed in this paper achieves state-of-the-art segmentation performance with few parameters on the YouTube-VIS dataset, demonstrating its efficiency and practicality. This method significantly enhances the application efficiency and adaptability of visual perception intelligent sensing technology in video data acquisition and processing, providing strong support for its widespread deployment. [ABSTRACT FROM AUTHOR]