bluuebunny/crossref_metadata_2025 huggingface dataset:
Ultrawide bandgap semiconductor h-BN for direct detection of fast neutrons
Authors: Li J. , Tingsuwatit A. , Alemoush Z. , Lin J. Y. , Jiang H. X.
Published: January 2025

III-nitride wide bandgap semiconductors have contributed on the grandest scale to many technological advances in lighting, displays, and power electronics. Among III-nitrides, BN has another unique application as a solid-state neutron detector material because the isotope B-10 is among a few elements that have an unusually large interaction cross section with thermal neutrons. A record high thermal neutron detection efficiency of 60% has been achieved by B-10 enriched h-BN detectors of 100 μm in thickness in our group. However, direct detection of fast neutrons with energies above 1 MeV is highly challenging due to the extremely low interaction cross section of fast neutrons with matter. We report the successful attainment of 0.4 mm thick freestanding h-BN 4″-diameter wafers, which enabled the demonstration of h-BN fast neutron detectors capable of delivering a detection efficiency of 2.2% in response to a bare AmBe neutron source. Furthermore, it was shown that the energy information of incoming fast neutrons is retained in the neutron pulse-height spectra. A comparison of characteristics between h-BN fast and thermal neutron detectors is summarized. Neutron detectors are vital diagnostic instruments for nuclear and fusion reactor power and safety monitoring, oil field exploration, neutron imaging and therapy, as well as for plasma and material science research. With the outstanding attributes resulting from its ultrawide bandgap (UWBG), including the ability to operate at extreme conditions of high power, voltage, and temperature, the availability of h-BN UWBG semiconductor detectors with the capability of simultaneously detecting thermal and fast neutrons with high efficiencies is expected to open unprecedented applications that are not possible to attain by any other types of neutron detectors.
Novel patterns in discrete Ikeda map: Quint points and complex non-quantum chirality
Authors: Liu Zeyi , Guo Xingzhao , Rao Xiaobo
Published: January 2025

In this paper, the complex and dynamically rich distribution of stable phases in the well-known discrete Ikeda map is studied in detail. The unfolding patterns of these stable phases are described through three complementary stability diagrams: the Lyapunov stability diagram, the isoperiod stability diagram, and the isospike stability diagram. The adding-doubling complexification cascade and fascinating non-quantum chiral pairs are discovered, marking the first report of such structures in discrete mapping. The inherent symmetry of the Ikeda map also leads to the emergence of even more complex chiral formations. Additionally, the effects of initial value perturbations on stable phase topology are explored, revealing that in near-conservative states, small changes in initial conditions significantly disturb the system, resulting in the discovery of a multitude of previously hidden shrimp islands. Our findings enhance the understanding of non-quantum chiral structures within discrete systems and offer new insights into the intricate manifestations of stability and multistability in complex mappings.
Maple leaf-based triboelectric nanogenerator for efficient energy harvesting and precision monitoring in ping-pong training
Authors: Yu He , Li Zheng
Published: January 2025

Triboelectric technology, with its renewable, low-cost, and eco-friendly advantages, offers new possibilities for intelligent motion-sensing equipment and sports monitoring. We propose a maple leaf-based triboelectric nanogenerator (ML-TENG) for green mechanical energy harvesting and detecting table tennis corner kicks. The ML-TENG operates in contact-separation mode and achieves a peak power output of 63.38 W/m3 at an optimal load of 50 MΩ. The experimental results show a transfer charge (Qsc) of 35 nC, a short-circuit current (Isc) of 9 μA, and an open-circuit voltage (Voc) of 50 V. Tested with a ping-pong paddle, the ML-TENG generates consistent voltage even under high-frequency impacts, demonstrating its sensitivity to both strong and weak forces. This ready-to-use design requires minimal preparation, highlighting triboelectric technology’s potential for improving sports monitoring accuracy and enabling real-time athletic performance analysis.
Reversing the acoustic contrast factor by tuning the medium can make focused beams trap cells in three dimensions
Authors: Li Shiyu , Gong Zhixiong
Published: January 2025

Three-dimensional (3D) selective trapping of particles and cells shows several potential applications such as reproductive cell selection, cell mechanics measurement, and in vivo rheology probes. Single-focused beams are a good candidate because of their simplicity, excellent selectivity, and strong trap. However, typical human cells in the water medium have the positive acoustic contrast factor and cannot be trapped in the focus of maximum intensity in a spherical focused beam as demonstrated recently [Gong and Baudoin, “Single beam acoustical tweezers based on focused beams: A numerical analysis of two-dimensional and three-dimensional trapping capabilities,” Phys. Rev. Appl. 18, 044033 (2022)]. To achieve the 3D trapping and meanwhile keep the viability of cells, we propose to use a cell-friendly medium (i.e., iodixanol solution) to reverse the acoustic contrast factor to negative. Numerical experiments are conducted for the breast cancer cell (Michigan Cancer Foundation-7, MCF-7) with the computation of the three-dimensional (3D) acoustic radiation forces based on the angular spectrum method. It is shown that 3D trapping of MCF-7 in iodixanol medium with a single focused beam is possible, both in and beyond the Rayleigh regime. This work provides a solution to use a simple focused beam for 3D trapping of typical human cells, which may be beneficial to single-cell analysis, cellular phenotyping, precise assembly of different cells in tissue engineering, and controlled drug delivery.
Modeling of oil churning power loss in spiral bevel gears under oil injection lubrication
Authors: Hu Shuai , Gong Wuqi , Ren Xinda
Published: January 2025

Spiral bevel gears are widely used in automobile transmission systems, and their performance plays a crucial role in driveline safety and transmission efficiency. However, studies on the lubrication performance and churning power loss of spiral bevel gears under an injection lubrication system are still insufficient. In this study, a numerical simulation model consisting of a nozzle, a spiral bevel gear pair, and a box was developed. The effects of different injection velocities, nozzle diameters, oil temperatures, and injection angles on the lubrication performance were simulated and analyzed. In addition, a churning loss prediction model was established by constructing an orthogonal scheme, dimensional analysis, and multiple linear regression, and a spiral bevel gear churning loss test rig was built to verify the accuracy of the prediction model. The results show that the injection velocity and nozzle diameter have a more pronounced effect on the oil volume fraction on the gear surface, while the lubricant temperature has little effect on it; the relative error between the predicted and experimental values of the established model is within 10%, which meets the industrial requirements. This work helps scholars to understand the lubrication mechanism of spiral bevel gears and provides a method to predict the churning power loss of spiral bevel gears under oil injection systems.
Numerical simulation of the influence of microchannel flow field on particle separation under changes in geometric structure
Authors: Zou Hongyuan , Han Wenbo , Zhong Yuhang , Yue Haoyu , Li Wei , Zhang Cunyou , Zhang Hongpeng
Published: January 2025

This paper systematically investigated the microfluidic chip with inertial contraction and expansion channels based on numerical simulation methods. The influence of geometric shape changes on the particle separation effect was focused on. We varied microchannel structural parameters such as contraction channel length and width, expansion channel length and width, and the overall curvature of the microchannel. The results indicated that different geometric structures hold diverse effects on the particle separation and particle recovery rate. An appropriate shrinkage–expansion ratio can improve the particle separation effect. In the microchannel, we found that six expansion channels and seven contraction channels are the optimal microchannel structure, which are capable of achieving effective separation of three types of particles. The vortex structure in the expansion channel dramatically impacts the focusing width of particles and the focusing distance of particles, which may be considered as the internal mechanism to explain the trajectory of particles in the channel. Furthermore, the curvature of the microchannel has a great influence on the particle recovery rate and particle separation effect. As the degree of bending leaps, the particle recovery rate will first decrease and then increase. This study establishes a theoretical foundation for understanding the interaction between diversifications in the geometric structure of microfluidic chips with inertial contraction and expansion channel structures and particle separation efficiency.
Wing–wing coupling enhances the aerodynamic performance of dragonflies during forward flight
Authors: Sun Wen , Wang Luyao , Wang Yan Qing
Published: January 2025

Dragonflies have garnered significant attention due to their ability to perform various complex flight maneuvers. As a dipteran insect, the wing–wing coupling between forewing and hindwing (FW and HW) in dragonflies plays a crucial role in aerodynamic performance. In this study, a numerical simulation model is developed to elucidate the impact mechanism of wing–wing coupling in dragonflies during forward flight. The results reveal that the wing–wing coupling mainly enhances the aerodynamic force for hindwing, thereby improving the aerodynamic performance of dragonflies. There is a synergy between flapping deviation angle and phase angle. Dragonflies with negative flapping deviation angle and a suitable phase angle about 45° can generate high horizontal force and propulsive efficiency significantly while maintaining the vertical force. The effect of wing–wing coupling is related to the wing spacing of dragonflies, and proves to be advantageous at small dimensionless wing spacing (less than 2.5). These findings deepen our understanding of the exceptional flight capabilities of dragonflies and provide valuable insights for the design of tandem flapping wings.
Wall-pressure-based spatial flow-field reconstruction and sensor arrangement optimization in a supersonic isolator
Authors: Wang Kai , Kong Chen , Chang Juntao
Published: January 2025

Sensing and reconstruction for supersonic flow field based on wall-pressure is promising. A new method for three-dimensional (3D) spatial flow-field reconstruction for the isolator of a scramjet is proposed, and a potential mapping between wall pressure and the spatial flow field has been established for the supersonic isolator. Combining theoretical methods and practical engineering applications, improved particle swarm optimization was used to optimize the sensor arrangements on the wall for the 3D flow field. The model successfully reconstructs the Mach-number field with high accuracy and learns the spatial mapping between the wall pressure in the flow channel and the supersonic Mach-number field. Hence, the 3D reconstruction model can capture the nonlinear physics and learn the spatial position effect and gradient effect in the supersonic isolator. This method can fully consider adding various restrictions and constraints while also taking into account the effectiveness of flow-field reconstruction and the guiding significance for practical engineering. A novel research approach is provided for predicting the 3D Mach-number field in the supersonic isolator, and the technical and methodological reference is provided for the exploration of the spatial supersonic flow field.
Energy budget analysis on roughness effects on propagation process of perturbations in compressible boundary layer
Authors: Yang Zepeng , Guo Xinliang , Wang Yuhan , Gao Zhenxun
Published: January 2025

Wall roughness has significant effects on hypersonic boundary layer transition. In this paper, the propagation process of linear perturbations passing two-dimensional single or double hump-type roughness elements is simulated under Mach number 5.92 using the harmonic linearized Navier–Stokes equation. For the first time, the kinetic energy budget analysis is adopted to study the influencing patterns and mechanisms of the humps on the perturbations. For cases with a single hump, the hump has little effect on low-frequency perturbations, since perturbations are first promoted by the non-parallelism mechanism in the region upstream of the hump and then suppressed above the hump due to the negative production term. At higher frequencies, the hump can significantly promote/suppress the perturbation below/above the synchronization frequency, which is mainly caused by the production and non-parallelism terms in the upstream region of the hump. For cases with double humps, when they are close, it is found that their effects on perturbations cannot be obtained by the linear superposition of their individual effect. The interaction between them can make the promotion or suppression effects on perturbations significantly weaker than their linear superposition. This is due to the fact that the first hump occupies the upstream region of the second hump and that the contribution of the second hump's upstream region is limited. Under the condition in this paper, until the distance between the two humps is greater than 14δ*, where δ* is the local boundary layer thickness, the magnitude of their interaction is less than 5%.
Computational fluid dynamics-population balance model approach with drag force of bubble swarms for polydispersed bubbly flow in continuous casting mold
Authors: Li Yu , Liu Zhongqiu , Xiong Yongtao , Yao Yuchao , Li Baokuan , Xu Guodong
Published: January 2025

This study employs computational fluid dynamics (CFD) coupled with the population balance model (PBM) to explore the sensitivity of the drag model for the predictive accuracy of the gas–liquid two-phase flow in continuous casting (CC) mold. Several single bubble drag models have been numerically evaluated for high turbulent intensity and gas flow rate operation parameters. Then, the influence of turbulence effect and bubble swarm mechanisms on bubble dynamic behaviors are investigated. The predicted mean bubble diameter and flow pattern were studied and compared with the experimental data. The results show that all single bubble drag models, except for the Grace model, can predict the bubble size distribution (BSD) well. Meanwhile, all models significantly overestimate the bubble diameter near the nozzle under high gas flow rate conditions. A novel drag correction factor based on local gas holdup and BSD is proposed, which takes into account both the hindrance effect of small bubbles and the accelerating effect of large bubbles. The proposed drag correction factor can accurately predict BSD and flow pattern transition in the CC mold under high gas holdup regions. Compared with the simulation results of the previous single bubble drag model, the mean relative error predicted by the novel drag correction factor is decreased by 69.33%.
Dynamics change of coal methane adsorption/desorption and permeability under temperature and stress conditions
Authors: He Yuhuan , Li Xijian , Xie Honggao , Li Xianxian , Xia Ting , Chen Shoukun
Published: January 2025

Methane adsorption/desorption and permeability measurements are critical for evaluating reserves and production potential in coalbed methane (CBM) extraction. The varying temperature and stress in CBM wells have an impact on these characteristics. To understand these effects, take the Wenjiaba mining area and the Qinglong mining area in Guizhou, China, as the research objects, which are called WJB and QL for short. Characterizing the coal's surface area and pore structure using low-field nuclear magnetic resonance and low-temperature nitrogen adsorption is essential for methane flow and storage. The coal's adsorptive capacity under in situ conditions was revealed by isothermal methane adsorption tests conducted at pressures ranging from 0 to 18 MPa at different temperatures. Triaxial stress-controlled adsorption experiments simulated the impact of effective stress on methane adsorption. Stress-permeability tests evaluated the stress sensitivity and its effect on the coal's methane transmission ability, a key factor in CBM well producibility. The results showed that increased temperature reduced adsorption capacity for WJB and QL coals by 14.2% and 16.3%, respectively, while desorption rates and diffusion coefficients increased, suggesting that higher temperatures enhance desorption and diffusion. However, higher coal ranks can hinder desorption. Effective stress application led to over a 90% decrease in both adsorption capacity and permeability, emphasizing the need for stress management in CBM extraction. These insights provide a theoretical framework for the interplay between coal's pore structure, adsorption/desorption properties, and permeability under different stress and temperature conditions, guiding the optimization of CBM extraction strategies for efficient and sustainable methane recovery.
Bubble dynamics near a flat wall and a cylinder within confined spaces
Authors: Shen Junwei , Tang Xiaofeng , Liu Wenda , Ma Shaowu , Luo Peng , Zhang Yuning , Zhang Yuning
Published: January 2025

This study systematically investigates the impact of a flat wall and a cylinder on bubble dynamics within a confined space. Based on the circle theorem and image method, a Kelvin impulse theoretical model considering the bubble motion is established. Based on high-speed photography experiments, typical experimental phenomena of bubble oscillation are qualitatively exhibited. The experimental bubble morphology evolution and centroid motion are compared with the theoretical results of the liquid velocity and the Kelvin impulse. The influence mechanisms of the liquid velocity and the Kelvin impulse are explored, and the impact of the cylinder and the flat wall on a bubble is quantitatively explored. The main conclusions are summarized as follows: (1) Kelvin impulse and liquid velocity distribution can effectively predict the bubble centroid's movement and the bubble interface motion, respectively; (2) when the bubble and the cylinder are of comparable size, the Kelvin impulse on the flat wall's surface is greater than that on the cylinder's surface, and the impact of a flat wall on the liquid velocity field is much greater than that of a cylinder; (3) as the bubble–cylinder and bubble–wall distances increase, the velocities of the bubble interface away from the cylinder and the flat wall decrease in the final stage of the collapse.
Physics-informed radial basis function neural network for efficiently modeling oil–water two-phase Darcy flow
Authors: Lv Shuaijun , Li Daolun , Zha Wenshu , Xing Yan
Published: January 2025

Physics-informed neural networks (PINNs) improve the accuracy and generalization ability of prediction by introducing physical constraints in the training process. As a model combining physical laws and deep learning, it has attracted wide attention. However, the training cost of PINNs is high, especially for the simulation of more complex two-phase Darcy flow. In this study, a physics-informed radial basis function neural network (PIRBFNN) is proposed to simulate two-phase Darcy flow of oil and water efficiently. Specifically, in each time step, oil phase and water phase equations are discretized based on the finite volume method, and then, the physics-informed loss is constructed according to the residual of their coupling equations, and the pressure is approximated by RBFNN. Based on the obtained pressure, another physics-informed loss is constructed according to the residual of discrete water phase equation and the water saturation is approximated by another RBFNN. For boundary conditions, we use “hard constraints” to speed up the training of PIRBFNN. The straightforward structure of PIRBFNN also contributes to an efficient training process. In addition, we have simply proved the ability of RBFNN to fit continuous functions. Finally, the experimental results also verify the computational efficiency of PIRBFNN. Compared with physics-informed convolutional neural network, the training time of PIRBFNN is reduced by more than three times.
Office tape is an effective tool for making ultrathin diamond
Authors: Lopatka Alex
Published: January 2025

The 1-µm-thick membrane is 5 cm wide, about an order of magnitude as large as diamond membranes produced by previous approaches.
The lessons learned from ephemeral nuclei
Authors: Nazarewicz Witold , Sobotka Lee G.
Published: January 2025

Recent experimental analyses of fleeting clusters of protons and neutrons put the very notion of the atomic nucleus in a new light.
An exchangeable SIM probe for monitoring organellar dynamics of necrosis cells and intracellular water heterogeneity in kidney repair
Authors: Lai Youbo , Zhang Tengteng , Huang Ling , Klymchenko Andrey S. , Lin Weiying
Published: January 2025

Monitoring subcellular organelle dynamics in real time and precisely assessing membrane heterogeneity in living cells are very important for studying fundamental biological mechanisms and gaining a comprehensive understanding of cellular processes. However, there remains a shortage of effective tools for these purposes. Herein, we propose a strategy to develop the exchangeable water-sensing probeAPBD for time-lapse imaging of dynamics in cellular membrane-bound organelle morphology with structured illumination microscopy at the nanoscale. In this work, our results reveal mitochondria as the first organelle to undergo morphological changes through swelling, fission, and fusion in cell necrosis, leading to the rupture of the endoplasmic reticulum (ER) sheet adhered to the mitochondria. Meanwhile, the ER tubules are then reconstructed by stretching and fusion of autophagosomes. Moreover, APBD allows us to directly visualize spatially resolved distribution of biomembranes vs. water inside single mammalian cells. Our findings show that the renal ischemia–reperfusion injury (IRI) model results in the increased biomembrane to cytoplasmic water ratio in the tissue. This reveals intracellular water heterogeneity between the nucleus and the cytoplasm during the IRI process. Overall, this study presents a strategy for development of the molecular tools for cellular water heterogeneity and organelle dynamics.
The proteome is a terminal electron acceptor
Authors: Flamholz Avi I. , Goyal Akshit , Fischer Woodward W. , Newman Dianne K. , Phillips Rob
Published: January 2025

Microbial metabolism is impressively flexible, enabling growth even when available nutrients differ greatly from biomass in redox state.
Escherichia coli
, for example, rearranges its physiology to grow on reduced and oxidized carbon sources through several forms of fermentation and respiration. To understand the limits on and evolutionary consequences of this metabolic flexibility, we developed a coarse-grained mathematical framework coupling redox chemistry with principles of cellular resource allocation. Our models inherit key qualities from both of their antecedents: i) describing diverse metabolic chemistries and ii) enforcing the simultaneous balancing of atom (e.g., carbon), electron, and energy (adenosine triphosphate) flows, as in redox models, while iii) treating biomass as both the product and catalyst of the growth process, as in resource allocation models. Assembling integrated models of respiration, fermentation, and photosynthesis clarified key microbiological phenomena, including demonstrating that autotrophs grow more slowly than heterotrophs because of constraints imposed by the intracellular production of reduced carbon. Our model further predicted that heterotrophic growth is improved by matching the redox state of biomass to the nutrient environment. Through analysis of

≈

60,000 genomes and diverse proteomic datasets, we found evidence that proteins indeed accumulate amino acid substitutions promoting redox matching. We therefore propose an unexpected mode of genome evolution where substitutions neutral or even deleterious to the individual biochemical or structural functions of proteins can nonetheless be selected due to a redox-chemical benefit to the population.
MYO18B promotes lysosomal exocytosis by facilitating focal adhesion maturation
Authors: Ren Wei-Wei , Kawahara Rebeca , Suzuki Kenichi G.N. , Dipta Priya , Yang Ganglong , Thaysen-Andersen Morten , Fujita Morihisa
Published: January 2025

Many cancer cells exhibit increased amounts of paucimannose glycans, which are truncated N-glycan structures rarely found in mammals. Paucimannosidic proteins are proposedly generated within lysosomes and exposed on the cell surface through a yet uncertain mechanism. In this study, we revealed that paucimannosidic proteins are produced by lysosomal glycosidases and secreted via lysosomal exocytosis. Interestingly, lysosomal exocytosis preferentially occurred in the vicinity of focal adhesions, protein complexes connecting the actin cytoskeleton to the extracellular matrix. Through genome-wide knockout screening, we identified that MYO18B, an actin crosslinker, is required for focal adhesion maturation, facilitating lysosomal exocytosis and the release of paucimannosidic lysosomal proteins to the extracellular milieu. Moreover, a mechanosensitive cation channel PIEZO1 locally activated at focal adhesions imports Ca2+ necessary for lysosome-plasma membrane fusion. Collectively, our study unveiled an intimate relationship between lysosomal exocytosis and focal adhesion, shedding light on the unexpected interplay between lysosomal activities and cellular mechanosensing.
Effects of intra-tumoral cellular heterogeneity of oxygen partial pressure on biological effectiveness of hydrogen-, helium-, carbon-, oxygen-, and neon-ion beams
Authors: Inaniwa Taku , Masuda Takamitsu , Kanematsu Nobuyuki
Published: January 2025

Objective. The tumor microenvironment characterized by heterogeneously organized vasculatures causes intra-tumoral heterogeneity of oxygen partial pressure

p

at the cellular level, which cannot be measured by current imaging techniques. The intra-tumoral cellular

p

heterogeneity may lead to a reduction of therapeutic effects of radiation. The purpose of this study was to investigate the effects of the heterogeneity on biological effectiveness of H-, He-, C-, O-, and Ne-ion beams for different oxygenation levels, prescribed dose levels, and cell types. Approach. The intra-tumoral cellular

p

distributions were simulated with a numerical tumor model for average oxygen pressures

p
¯

t

ranging from 2.5 to 15 mmHg. The relative biological effectiveness (RBE)-weighted dose distributions of 3–15 Gy prescribed doses were planned for a cuboid target with the five ion species for constant

p
¯

t

values. Radiosensitivities of human salivary gland tumor (HSG) and Chinese hamster ovary (CHO) cells were investigated. The planned dose distributions were then recalculated by taking the

p

heterogeneity into account. Main results. As

p
¯

t

decreased and prescribed dose increased, the biological effectiveness of the ion beams decreased due to the

p

heterogeneity. The reduction in biological effectiveness was pronounced for lighter H- and He-ion beams compared to heavier C-, O-, and Ne-ion beams. The RBE-weighted dose in the target for HSG (CHO) cells decreased by 41.2% (44.3%) for the H-ion beam, while it decreased by 16.7% (14.7%) for the Ne-ion beam at a prescribed dose of 15 Gy under a

p
¯

t

of 2.5 mmHg. Significance. The intra-tumoral cellular

p

heterogeneity causes a significant reduction in biological effectiveness of ion beams. These effects should be considered in estimation of therapeutic outcomes.
Defect related vortex dynamics behaviors in ‘1144’-type iron-based superconductors
Authors: Li Yigang , Liu Cong , Chen Dong , Yi Xiaolei , Wang Lubin , Tang Qingbin , Li Fangtao , Wang Chunlei , Yu Benhai , Ma Yanwei
Published: January 2025

We have synthesized ‘1144’- type (Ca1–x
Pr
x
KFe4As4 and CaKFe4As4) and ‘122’-type (Ba0.6K0.4Fe2As2 and Ba0.6Rb0.4Fe2As2) iron-based superconductors. Based on these crystals, we have investigated the vortex dynamics of the ‘1144’- and ‘122’-type iron-based superconductors. The results indicate that the novel flux dynamics behaviors of the ‘1144’-type iron-based superconductors are closely related to their defect structures. First, the intergrowths in ‘1144’-type superconductors can function as columnar defects under an applied magnetic field H∥ab-plane, which results in a dip structure in the magnetization hysteresis loops (MHLs) near zero field due to the self-field effect. Second, the intergrowths, as strong pinning sites, provide a large pulling force on the flux lines and cause a small magnetization peak at temperatures below 10 K under magnetic fields from about 3–7 T in MHLs for the ‘1144’-type superconductors. Third, there may be vortex entanglement due to the presence of strong pinning centers, which impedes the elastic-to-plastic motion of vortices (E–P phase transition) resulting in a weak second magnetization peak (SMP) effect in the bulk ‘1144’-type superconductors. Fourth, the intergrowths introduce disorder into the superconductors and accelerate the magnetic 3D-to-2D transition, which causes the thickness-dependent J
c and SMP effects due to the rigidity of flux lines with decreasing sample thickness. The current results are significant for our understanding of the relationship between the flux pinning behaviors and the defect structures for a superconductor.
Breakdown conditions of a multi-electrode low temperature atmospheric pressure plasma source
Authors: Gillies R M , Tompkins J , McKay K
Published: January 2025

Low-temperature atmospheric pressure plasma jets are generally small in scale (∼few mm) and often require high-breakdown voltages and high value gases to operate. This study investigates the advantageous properties of a novel multi-electrode jet-like source with separately powered (180° phase-shifted) live electrodes, namely significantly reduced breakdown voltage, increased operating voltage range and higher gas admixture capabilities. Gas breakdown voltage trends are demonstrated across multiple physical parameters, including tube diameter, electrode spacing and frequency. The potential uses of a safer, more practical discharge system are highlighted, as well as the conditions across the 3 kHz–30 kHz range under which plasma parameters are varied. An electrical analysis was also performed to provide a better understanding of the plasma characteristics beyond that of gas breakdown, specifically that of potential mode transitions that have not been taken into account in prior works.
Continuous-variable quantum secure direct communication based on N-APSK with Boltzmann-Maxwell distribution
Authors: Cao Zheng-Wen , Zhang Yu-Jie , Chai Geng , Liang Zhang-Tao , Chen Xin-Lei , Wang Lei , Wang Yu-Jie
Published: January 2025

Continuous-variable quantum secure direct communication (CVQSDC) with Gaussian-modulation (GM) demands a considerable quantity of random numbers during the preparation process and encodes them separately on the quadrature components of the quantum states. Hence, high-speed random number generators are required to satisfy the demand, which is difficult to implement in practical applications. CVQSDC with discrete-modulation (DM), correspondingly, employs a finite number of quantum states for achieving encoding, which can circumvent the shortcomings existing in the GM scheme. Based on the advantages of DM, the issue of attaining the most optimal secrecy capacity and communication distance remains to be resolved. Here, we propose a CVQSDC protocol based on N-symbol amplitude phase shift keying (N-APSK), which exploits the Boltzmann-Maxwell distribution assisted probability shaping technique. In comparison with the uniform distribution, according to 32-APSK CVQSD, the proposed scheme extends the communication distance by about 38%, while obtaining higher secrecy capacity at the same communication distance. Furthermore, increasing the value of N will concurrently increase the quantity of rings in the constellation, thereby facilitating enhancements in communication distance. This work incorporates the modulation approaches prevalently employed in classical communication into the realm of quantum communication, attaining gratifying advancements in communication distance and secrecy capacity, and concurrently facilitating the integrated development of quantum communication and classical communication.
Effect of spherical Mo metal particles on microstructure and properties of 316L stainless steel during laser powder bed fusion
Authors: Zhang Hao , Yang Lijun , Zhang Zhenmeng , Chen Zhihao , Song Ziliang , Wang Chenyang , Wu Xihui , Zhu Xiebin
Published: January 2025

Aiming at the performance defects of 316L stainless steel (316LSS), such as low surface hardness, low strength, and poor resistance to chloride ion pitting, Mo/316L particle-reinforced metal matrix composites (PRMMCs) were prepared in this paper using the laser powder-bed fusion (L-PBF) process. It was found that the addition of Mo particles significantly affected the solidification behavior and organization of the matrix and formed a unique spherical metal reinforcement in the matrix, which significantly enhanced the strength of the material while avoiding a serious loss of plasticity: compared with PBF-316L, the ultimate tensile strength (UTS) and elongation of 2Mo/316L with 2 wt% Mo particles added were simultaneously increased by 9.7% and 10.4%, which is a good result of improving strength and plasticity at the same time. With the addition of 6 wt% Mo particles, the UTS of 6Mo/316L reaches 952 MPa while still maintaining a good elongation of 21%. In addition, the hardness, wear resistance and corrosion resistance of the Mo/316L material were significantly improved to varying degrees. This overall improvement in the performance defects of 316LSS is difficult to achieve with other types of reinforcing particles, demonstrating the potential application of using such spherical refractory metal particles for the preparation of PRMMCs in the L-PBF process.
A practical case study on effect of moisture ingress in power cables and methods to reduce equipment failure
Authors: Gugulothu Babu Naik , Lakshminarayanan Sanjay , Palati Madhu , Haleyur Lakshmegowda Suresh , Bukya Mahipal
Published: January 2025

Over the past few years, there has been a rise in the quantity of underground cables used in power transmission and distribution networks in many urban areas worldwide. Technological and economic considerations, along with space constraints, are responsible for this increase. As the number of cables increases, utilities face challenges in effectively maintaining and testing their condition. Particularly, the maintenance of medium-voltage cables, such as three-core 33 kV cables, is becoming increasingly challenging. One of the biggest problems with medium-voltage cables is their preference when the load is closer to the substation. Because the cables are closer to the source, the probability of the end termination kit failing is higher, leading to short-line faults (SLF). Short-line faults subject the connected switchgear and transformers to severe electrical, thermal, and mechanical stresses. Cable faults can cause equipment failure, resulting in external flashovers, which in turn raise the temperature and ultimately lead to insulator failure. Low external temperatures can increase moisture content in the environment, leading to equipment failure. This paper investigates switchgear failures in 132/33 KV substations caused by cable faults and ambient temperature and presents methods to mitigate switchgear and instrument transformer failures caused by cable faults. Over time, the proposed methods have led to a decrease in the number of failures. In recent years, protocols such as IEC61850, MODBUS, IEC60870-4, and others have transformed conventional substations into automated substations. We propose a low-cost, practically feasible solution using the GOOSE technique in the IEC61850 protocol to prevent the flashover of the circuit breakers, following a detailed investigation.
Fault diagnosis of wind turbine with few-shot learning based on acoustic signal
Authors: Yang Shuai , Xu Hanfeng , Wang Yu , Chen Junhong , Li Chuan
Published: January 2025

Due to the harsh working conditions of wind turbines, it is difficult to obtain sufficient fault data from the gearbox. To address this issue, this study proposes a graph neural network model based on few-shot learning (GNN-FSL) for the fault diagnosis on planetary gears of wind turbine gearbox with acoustic signals. The short-time Fourier transform (STFT) is chosen for preprocessing of acoustic signals as input data, which converts the raw data into two-dimensional data. Then, convolutional neural networks (CNN) are used to extract data features. Finally, the extracted features are input for the graph neural network for fault classification. The experimental results show that the model performs well in fault classification on small sample datasets, providing an effective method for fault diagnosis of planetary gears in wind turbines. By comparing EfficientNet-b0, ResNet-50, Densenet121, Mobilenet_v2 and DiffKendall models, it is verified that the proposed method is effective in planetary gear fault classification, and its performance is superior to all these networks.
Electro-osmotic flow in channel: effects of superhydrophobic surface structures sizing
Authors: Jing Mei , Yu Kok Hwa , Aziz Mohd Sharizal Abdul , Chang Wei Shyang
Published: January 2025

Numerical study on electro-osmotic flow over superhydrophobic transverse grooves and ribs have been explored. With uncharged liquid-gas interface, smaller electro-osmotic axial flow is attained. The electro-osmotic axial flow is found to be significantly influenced by the gas area fraction and the normalized groove-rib spacing. In the presence of the liquid-gas interfaces, slip flows are observed over these interfaces, consistent with that reported in pressure-driven flow. As the flow is permitted in the vicinity of the liquid-gas interface, flow redistribution is observed along the channel. Higher bulk flow with reducing flow magnitude is observed close to the wall when solid wall is present, and vice versa. Despite the alteration of the axial flow, conservation of flow along axial direction is attained. To estimate the normalized electro-osmotic axial flow for this flow condition, a new correlation formulation is proposed to accurately predict the averaged axial flow magnitude for different values of gas area fraction and normalized groove-rib spacing in the range between 0.1 and 4.
3D Breast Scanning in Plastic Surgery Utilizing Free iPhone LiDAR Application: Evaluation, Potential, and Limitations
Authors: Kyriazidis Ioannis , Berner Juan Enrique , Waked Karl , Hamdi Moustapha
Published: January 2025

Background

Three-dimensional (3D) imaging enhances surgical planning and documentation in plastic surgery, but high costs limit accessibility. Mobile light detection and ranging (LiDAR) technology offers a potential cost-effective alternative.

Objectives

The objective of this research was to evaluate the accuracy and clinical utility of iPhone-based LiDAR scanning for breast measurements compared to traditional methods, and to establish standardized protocols for clinical implementation.

Methods

In this prospective validation study, 25 consecutive patients (mean age: 44 years; range: 32-64 years; mean BMI: 23.2 kg/m2) undergoing breast procedures were evaluated with the “3D Scanner App” on the iPhone 15 Pro (Apple Inc., Cupertino, CA). Three standardized measurements (sternal notch-to-nipple, nipple-to-midline, nipple-to-inframammary fold) of LiDAR and manual techniques were compared. Technical error of measurement (TEM) and relative TEM (rTEM) were calculated. Interrater reliability, learning curve assessment, and cost-effectiveness analysis were performed.

Results

LiDAR measurements showed very good accuracy for sternal notch-to-nipple (rTEM 1.43%, 95% CI: 1.21-1.65) and nipple-to-midline (rTEM 2.83%, 95% CI: 3.12-3.78) distances. Nipple-to-inframammary fold measurements showed poor accuracy (rTEM 13.05%, 95% CI: 8.21-9.39). Interrater reliability was excellent (ICC = 0.92). Learning curve analysis demonstrated measurement stability after 5 cases. Cost analysis revealed 97.8% reduction in initial investment compared to commercial 3D imaging systems.

Conclusions

Mobile LiDAR offers a cost-effective tool for breast surgery planning and documentation. While measurements like sternum-to-nipple and nipple-to-midline are highly accurate, the relatively poor accuracy of nipple-to-IMF highlights limitations with complex curves. As this technology continues to evolve, further improvements in accuracy are anticipated, expanding its role in clinical use.

Level of Evidence: 4 (Therapeutic)
KPRR: a novel machine learning approach for effectively capturing nonadditive effects in genomic prediction
Authors: Li Mianyan , Hall Thomas , MacHugh David E , Chen Liang , Garrick Dorian , Wang Lixian , Zhao Fuping
Published: January 2025

Nonadditive genetic effects pose significant challenges to traditional genomic selection methods for quantitative traits. Machine learning approaches, particularly kernel-based methods, offer promising solutions to overcome these limitations. In this study, we developed a novel machine learning method, KPRR, which integrated a polynomial kernel into ridge regression to effectively capture nonadditive genetic effects. The predictive performance and computational efficiency of KPRR were evaluated using six datasets from various species, encompassing a total of 18 traits. All the traits were known to be influenced by additive, dominance, or epistatic genetic effects. We compared the performance of KPRR against six other genomic prediction methods: SPVR, BayesB, GBLUP, GEBLUP, GDBLUP, and DeepGS. For datasets dominated by additive effects, KPRR achieved superior prediction accuracies in the wheat dataset and comparable performance in the cattle dataset when compared to GBLUP. For datasets influenced by dominance effects, KPRR matched GDBLUP in accuracies in the pig dataset and outperformed GDBLUP in the sheep dataset. For datasets exhibiting epistatic effects, KPRR outperformed other methods in some traits, while BayesB showed superior performance in others. Incorporating nonadditive effects into a GBLUP model led to overall improvements in prediction accuracy. Regarding computational efficiency, KPRR was consistently the fastest, while BayesB was the slowest. Our findings demonstrated that KPRR provided significant advantages over traditional genomic prediction methods in capturing nonadditive effects.
A transformer-based deep learning survival prediction model and an explainable XGBoost anti-PD-1/PD-L1 outcome prediction model based on the cGAS-STING-centered pathways in hepatocellular carcinoma
Authors: Wang Ren , Liu Qiumei , You Wenhua , Wang Huiyu , Chen Yun
Published: January 2025

Recent studies suggest cGAS-STING pathway may play a crucial role in the genesis and development of hepatocellular carcinoma (HCC), closely associated with classical pathways and tumor immunity. We aimed to develop models predicting survival and anti-PD-1/PD-L1 outcomes centered on the cGAS-STING pathway in HCC. We identified classical pathways highly correlated with cGAS-STING pathway and constructed transformer survival model preserving raw structure of pathways. We also developed explainable XGBoost model for predicting anti-PD-1/PD-L1 outcomes using SHAP algorithm. We trained and validated transformer survival model on pan-cancer cohort and tested it on three independent HCC cohorts. Using 0.5 as threshold across cohorts, we divided each HCC cohort into two groups and calculated P values with log-rank test. TCGA-LIHC: C-index = 0.750, P = 1.52e−11; ICGC-LIRI-JP: C-index = 0.741, P = .00138; GSE144269: C-index = 0.647, P = .0233. We trained and validated [area under the receiver operating characteristic curve (AUC) = 0.777] XGBoost model on immunotherapy datasets and tested it on GSE78220 (AUC = 0.789); we also tested XGBoost model on HCC anti-PD-L1 cohort (AUC = 0.719). Our deep learning model and XGBoost model demonstrate potential in predicting survival risks and anti-PD-1/PD-L1 outcomes in HCC. We deployed these two prediction models to the GitHub repository and provided detailed instructions for their usage: deep learning survival model, https://github.com/mlwalker123/CSP_survival_model; XGBoost immunotherapy model, https://github.com/mlwalker123/CSP_immunotherapy_model.
Hydrogen supply pipeline leakage diffusion and safety assessment for fuel cell patrol vehicle
Authors: Liu Shuai , Hao Liutao , Jia Hekun , Zhang Qiushi , Du Pengzhu
Published: January 2025

This study aims to reveal the hydrogen leakage and diffusion characteristics of the hydrogen supply pipeline in a fuel cell patrol vehicle and to evaluate the damage distance following an explosion. Through numerical analysis, the impact of the position, diameter, shape, and direction of leakage holes, as well as ambient wind, on hydrogen diffusion was discussed. The results show that different leakage positions are affected by surrounding objects and the height above the ground, altering the volume and diffusion distance of the flammable hydrogen cloud (FHC). An increase in leakage aperture leads to a significant rise in hydrogen leakage, the volume of the FHC, and the damage range after an explosion. The shape of the leakage hole affects the velocity distribution of hydrogen upon impacting a wall, resulting in a different distribution of the FHC. When the leakage direction is 180°, the volume of the FHC decreases by 79.2%. Environmental winds significantly influence hydrogen diffusion, with lateral winds reducing the volume of the FHC by 74%. The maximum hazard radius of hydrogen leakage is 4.09 m, the maximum distance for multiple fatalities caused by a hydrogen explosion is 1.48 m, and the maximum distance for minor injuries is 6.04 m.
Investigation of consistency and uniformity for commercial-size proton-exchange membrane fuel cell stack based on multipoint impedance measurement
Authors: Zhou Julong , Zhou Yuhan , Li Ruitao , Yao Naiyuan , Lin Weikang , Ma Tiancai
Published: January 2025

The proton-exchange membrane fuel cell is a highly attractive clean energy technology for the future. However, differences in the consistency and uniformity of commercial-size fuel cell stacks significantly impact their health status and lifespan. This study is based on a commercial-size 10-cell stack. First, the characteristic frequency was determined by multipoint voltage and impedance sweeping experiments. Subsequently, the consistency and uniformity of the output characteristics of the stack at various loads under standard operating conditions were comprehensively analyzed using fixed-frequency multipoint impedance. Finally, a sensitivity analysis was conducted to quantitatively assess the effects of key parameters, including the air stoichiometry ratio and operating temperature, on the consistency and uniformity of voltage and high-frequency resistance. The inconsistency is more pronounced at high current densities, especially at the cathode inlet side compared to the outlet side. At low-current-density operation, the high-frequency resistance is greater at the cathode inlet side compared to the outlet side due to uneven gas distribution and more severe membrane drying at the inlet side. Increasing the air stoichiometry ratio enhances the consistency and uniformity of the stack. The effect of temperature on stack consistency is not significant in the appropriate temperature interval, but higher temperatures can reduce cell uniformity differences. The analytical approach in this study can provide guidance for stack consistency and uniformity studies.