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Quantum gravitational corrections at third-order curvature, acoustic analog black holes and their quasinormal modes
No full textQuasinormal modes for bosonic (scalar, electromagnetic, and axial gravitational) and fermionic field perturbations, radiated from black holes that carry quantum gravitational corrections at third order in the curvature to the Schwarzschild solution, are scrutinized from the propagation of analog transonic sound waves across a de Laval nozzle. The thermodynamic variables, the nozzle geometry, the Mach number, and the thrust coefficient are computed as functions of the parameter driving the effective action for quantum gravity containing a dimension-six local operator beyond general relativity. The quasinormal modes for quantum gravitational corrected analog black holes are also determined for higher overtones, yielding a more precise description of the quantum-corrected ringdown process and the gravitational waveform way before the fundamental mode sets in
Bi-directional reflectance, polarization, and spectroscopic measurements of the Chang'e-5 regolith sample
No full textContext. Optical measurement is a powerful tool for retrieving the regolith physical properties of the lunar surface.
Aims. It has been a long-standing question in planetary remote sensing whether laboratory measurements are consistent with remote sensing measurements. The sample return mission of Chang’e-5 (CE5) has provided an opportunity to answer this question.
Methods. For this work we performed photometric, linear and circular polarimetric, and reflectance spectroscopic measurements of the Chang’e-5 surface scooped regolith (soil) sample CE5C0600.
Results. Our results show that the CE5 regolith exhibits both a strong opposition effect and a pronounced forward-scattering lobe, and a moderate contrast between its minimum and maximum reflectance values compared to the in situ measurements of Chang’e-3 and −4. A slight monotonic phase reddening trend is observed with increasing phase angle, while no clear colorimetric opposition effect was found at small phase angles The regolith shows maximum linear polarization at large phase angles, ∼16 at 633 and ∼21% at 532 nm, slightly higher than the values reported in ground-based observations and laboratory measurements on the Apollo and Luna samples. The circular polarization ratio increases as the phase angle decreases, consistent with previous observations of the Apollo samples. Compared with orbital, in situ,and ground-based observations of the CE5 landing site, the laboratory-measured regolith exhibits higher reflectance but a very similar spectral slope, suggesting a higher degree of compaction in the Earth environment.
Conclusions. Studies of lunar samples with varying porosities and space weathering degrees are needed to better understand their behavior under in situ condition, enabling their use as a reliable ground truth for current and future Lunar missions
Effect of transport processes on elliptic flow centrality dependence under different initial conditions in the AMPT model
No full textUsing the AMPT model, we study charged hadron elliptic flow () centrality dependence in Au+Au collisions at . We find distinct centrality-dependent roles for partonic () and hadronic () transport processes. In central collisions, is dominantly amplified by larger (reducing partonic viscosity) but insensitive to . In peripheral collisions, larger (reducing hadronic viscosity) significantly enhances , flattening its centrality dependence and improving agreement with STAR data. Initial pressure gradients (enhanced by Lund parameter ) also increase , while affects spectra but not flow. This centrality-differential sensitivity to and provides a novel strategy for extracting phase-specific shear viscosities
Information criteria for selecting parton distribution function solutions
No full textIn data-driven determination of Parton Distribution Functions (PDFs) in global QCD analyses, uncovering the true underlying distributions is complicated by a highly convoluted inverse problem. The determination of PDFs can be understood as the inference of a function supported on [0, 1], a problem that admits multiple acceptable solutions. An ensemble of solutions exists that pass all standard goodness-of-fit criteria. In this paper, we propose algorithms for the classification, clustering, and selection of solutions to the determination of PDFs, or any functions on [0, 1], based on the characterization of their shape. We explore information-theoretic based (Rényi entropy and divergence) and optimal-transport based (Wasserstein distance) criteria. In particular, we advocate for the use of the Rényi entropy as an absolute estimator per solution, as opposed to relative estimators that compare solutions pairwise. We show that the Rényi entropy can characterize the space of solutions w.r.t. the PDF shapes. Paired with the identification of the optimal combination of solutions via Pareto fronts, it provides a plausible and minimalist selection algorithm. Moreover, Rényi entropy proves versatile for use in clustering applications
A method for tail rotor aerodynamic force prediction under rotor interference based on coupled momentum source and blade element theory
No full textDue to the influence of slip flow and wake, the tail rotor of a helicopter may produce strong unsteady aerodynamic force in its main rotor interference flow field, which may affect the helicopter control and lead to structural failure. Although the unsteady flow field simulation method can capture the details of the flow field, the calculation amount is large. Therefore, this paper presents a fast method of tail rotor aerodynamic force prediction based on coupled momentum source and blade element theory. The momentum source model takes into account the disturbance of the flow field of a main rotor to that of a tail rotor. The induced velocity of the tail rotor is extracted from the flow field, and its quasi-steady aerodynamic force is solved iteratively with the blade element theory. In order to verify the accuracy of the method, this paper carries out the prediction of the tail rotor's aerodynamic characteristics under the main rotor's interference with different sideslip angles. In the range of 0° to 30° sideslip angles, the error of the tail rotor's average pull coefficient obtained with the fast prediction method is 2.31% to 4.50% compared with the wind tunnel experiment. Compared with the experiment, the error of the unsteady flow simulation method using the sliding grid is -4.50% to 1.20%, but the calculation amount of the experiment is only 9.61%. In the forward flight state of a small sideslip, regardless of whether the rotor slip sweeps the tail rotor, compared with the tail rotor's average pull predicted with the unsteady flow simulation method, the error of the fast prediction method is -6.19% to 6.15%. The average value of the unsteady pull coefficient of a single blade and the peak value of the first and second order blade passing frequency are close to those of the unsteady flow simulation method
Prediction of Potential Distribution of Red Imported Fire Ant in China Using the MaxEnt Model
No full textSolenopsis invicta Buren is a highly invasive and aggressive species. Since its invasion into China, it has rapidly spread to many regions, seriously threatening the local ecological balance and posing a huge threat to human life safety and agricultural production. To explore the suitable range of Solenopsis invicta Buren in China, this paper based on the distribution data obtained from GBIF database and the environmental factors obtained from the worldclim website to predict the potential geographical distribution of Solenopsis invicta Buren in China under historical climate conditions by MaxEnt model. The results show that the area under the ROC curves (AUC) of the training data is 0.967, which is reliable. Under the historical climate conditions, the potential suitable areas of Solenopsis invicta Buren in China are concentrated in Guangdong, Guangxi, Yunnan, Fujian, Hainan, Taiwan and other provinces. The mean temperature of coldest quarter (bio11) is the most important environmental factor affecting the suitable habitat of Solenopsis invicta Buren in China. The prediction can provide a scientific reference for monitoring the spread of Solenopsis invicta Buren and strengthening the prevention and control management
Comparative Mechanistic Fitness and Clinical Translation of CAR-T Cells, Immune Checkpoint Inhibitors, and Antibody–Drug Conjugates in NSCLC
No full textImmunotherapy has become a cornerstone of treatment for non-small cell lung cancer (NSCLC). This review summarizes the major immunotherapy strategies: immune checkpoint inhibitors (ICIs), antibody-drug conjugates (ADCs), and chimeric antigen receptor T cell (CAR-T) therapy and analyzes how their mechanisms align with distinct tumor immune phenotypes. Specifically, ICIs, through PD-1/PD-L1 blockade, restore antitumor immunity in "hot" tumors and produce durable survival benefits across multiple stages of NSCLC. In contrast, ADCs deliver cytotoxic payloads via target-specific antibodies, thereby offering immune-independent efficacy in "cold" or ICI-refractory tumors. However, toxicities such as interstitial lung disease may be dose-limiting. Transitioning to CAR-T therapy, although this approach is highly effective in hematologic malignancies, it remains experimental in NSCLC due to antigenic heterogeneity, poor T cell infiltration, and a suppressive tumor microenvironment. Notably, early studies, including intrapleural administration of mesothelin-targeted CAR-T cells combined with PD-1 blockade, have demonstrated local activity and safety. By combining mechanistic insights from ICIs and ADCs with next-generation CAR-T engineering, future development of more adaptable immunotherapies for solid tumors may be guided. Keywords: Non-small cell lung cancer (NSCLC); immune checkpoint inhibitors (ICIs); antibody-drug conjugates (ADCs); CAR-T cell therapy; tumor microenvironment; antigen heterogeneity; immunotherapy resistance
Design of linear feedback shift register with single event upset resistance
No full textThe rapid development of China's aerospace industry has rendered the radiation-hardened integrated circuit design critically importance, especially for spacecraft chips requiring protection against cosmic high-energy particle effects. As a fundamental component of built-in self-test (BIST) structures that ensure chip reliability, the radiation hardening of linear feedback shift register (LFSR) necessitates special attention. A comprehensive radiation-hardening methodology for LFSRs through systematic analysis of single-event upset (SEU) mechanisms is proposed. The present approach integrates four synergistic design strategies. Firstly, a radiation-hardened D-flip-flop architecture by using 12-transistor dual-interlocked storage cells (DICE) with bit-line separation technique is implemented. Secondly, at the layout level, radiation hardening capability is enhanced through the implementation of guard rings, sensitive node area minimization and increased spacing between complementary sensitive nodes. Thirdly, a novel power-on-reset (POR) circuit with SEU-immune characteristics is developed to address initialization vulnerabilities. Finally, for XOR gates executing linear operations, the present design integrating C-element with bit-line separation techniques to resist SEU effects. Experimental validation through a 7-stage LFSR demonstrates that the radiation-hardened structure achieves significant SEU immunity enhancement while maintaining operational stability in radiation environments
Deep Learning for Dental Caries Diagnosis and Clinical Applications
No full textDental caries, a prevalent disease with significant health and economic consequences, goes undiagnosed during the early phases of its progression since conventional diagnostic methods like visual inspection and radiography possess low sensitivity as well as inter-observer consensus. This review discusses the use of deep learning (DL) for the automatic detection and grading of caries, comparing systematically different imaging modalities, such as bitewing and periapical radiography, intraoral photography, optical coherence tomography (OCT), cone-beam computed tomography (CBCT), and laser fluorescence, and their implications in caries diagnosis. It emphasizes how DL models, especially convolutional neural networks (CNNs), Transformers, and U-Net architectures, perform well in classification, detection, and segmentation tasks with expert-level performance and quantitation of lesions. They facilitate diverse clinical applications such as tele dentistry and personalized treatment planning and are advancing with multimodal data fusion, explainable AI, and real-time processing. However, there are still challenges regarding limited annotated datasets, model generalizability, computational requirements, and clinical interpretability. The review aims to promote clinical translation by summarizing recent advances, comparing methodologies, and pointing out future directions for intelligent oral healthcare
A new Rényi holographic dark energy model and its cosmological implications
No full textWe develop a generalized holographic dark energy model based on the Rényi entropy, which introduces a logarithmic deformation of the Bekenstein–Hawking entropy and is characterized by a non-extensivity parameter . By adopting the future event horizon as the infrared cutoff, we formulate the New Rényi Holographic Dark Energy (NRHDE) scenario and derive a modified holographic energy density that reduces smoothly to the standard HDE limit for . Starting from the Rényi entropy formalism, we obtain a closed and self-consistent set of evolution equations for the dark energy density parameter , the equation-of-state parameter , and the deceleration parameter q. We perform a detailed numerical investigation of the background dynamics over a physically reasonable range of the holographic parameter c and the Rényi deformation parameter , and show that the NRHDE model predicts a late-time phantom regime over an extended region of the parameter space, with a smooth approach toward the cosmological-constant boundary as either parameter increases. We further provide a global characterization of the parameter space by means of two-dimensional maps of the present-day equation-of-state parameter and the transition redshift, which clarify the joint impact of on the late-time cosmological evolution. Finally, a qualitative comparison between the NRHDE background predictions and observational Hubble data from cosmic chronometers is presented as a consistency check of the model at the background level. The NRHDE framework therefore constitutes a minimal and thermodynamically motivated extension of holographic dark energy, offering a flexible platform for future quantitative tests with late-time expansion data