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关键词： Holographic principle   dark energy   (2+1)-dimensional spacetime   data analysis  

摘要： In this study we explore the cosmic holographic principle, as proposed by [W. Fischler and L. Susskind, Holography and cosmology, arXiv:hep-th/9806039 within the framework of (2 + 1)-dimensional cosmological models. A generalized equation of state is employed, given by p = (zeta - 1)(rho + rho(0 where zeta and rho(0) are treated as two free parameters. The analysis confirms the validity of the holographic principle in all flat and open universes. However, for a (2 + 1)-dimensional closed universe, we apply the method proposed by [N. Kaloper and A. Linde, Cosmology versus holography, Phys. Rev. D 60 (1999) 103509] and observe that the holographic principle is generally not satisfied. Furthermore, we examine the stability of the proposed model using the Markov Chain Monte Carlo (MCMC) method, and estimate the best-fit values for the model parameters based on observational Hubble datasets.

关键词： Diurnal LST   machine learning   SHAP method   extreme heatwaves   SDGSAT-1  

摘要： Understanding how urban morphological structure regulates land surface temperature (LST) is critical for mitigating the urban heat island (UHI) effect under extreme heatwave conditions. However, the interactive and threshold effects of urban morphology on diurnal LST variation remain insufficiently understood. In this study, diurnal LST was retrieved from high-resolution, radiometrically consistent thermal infrared data acquired by SDGSAT-1. A two-dimensional (2D)-three-dimensional (3D) urban morphology indicator system was constructed using multi-source remote sensing datasets describing buildings, vegetation, and anthropogenic activity. XGBoost models combined with SHapley Additive exPlanations (SHAP) were applied to quantify nonlinear and interactive effects on daytime and nighttime LST. The results indicate that 1) vegetation and building environments dominate daytime LST variations, whereas nighttime LST is jointly influenced by vegetation, buildings, and anthropogenic factors;(2) tree height (TH) and building height (BH) exhibit nonlinear response relationships revealed by SHAP, with enhanced daytime cooling but intensified nighttime warming when TH exceeds similar to 15 m and BH surpasses similar to 10 m;and (3) interaction effects show that high TH and BH combined with low building density (BD) produce optimal daytime cooling, while elevated vertical morphology is associated with higher nighttime LST.

关键词： Water body extraction   CA-U-HRNet   time-series sentinel-1 SAR   Poyang Lake region   inundation frequency  

摘要： Accurate acquisition of high-resolution water body information is essential for watershed ecological management and flood monitoring. However, existing deep learning models face challenges in extracting water bodies from SAR imagery, including incomplete detection of small water bodies and confusion between water and shadow regions. Therefore, we developed an improved SAR-based water extraction model by integrating the coordinate attention mechanism with U-shaped high-resolution network (CA-U-HRNet). To verify the effectiveness of the proposed method, CA-U-HRNet was applied to time-series Sentinel-1 imagery of the Poyang Lake region for dynamic monitoring and spatiotemporal evolution analysis of open water extent from 2015 to 2025. Experimental results show that the model achieved an mIoU of 93.27% on the Sentinel-1 water body dataset, outperforming mainstream semantic segmentation models such as U-Net, PSPNet, DeepLabV3+, and OARENet. This indicates that incorporating coordinate attention enables CA-U-HRNet to better capture features and enhance spatial sensitivity by combining channel and positional information. Furthermore, the time-series monitoring results reveal seasonal fluctuations in the open water extent of the Poyang Lake region over the past decade, characterized by substantial expansion during the high-water period and contraction during the low-water period. In addition, the inundation frequency of water bodies gradually decreases outward from river channels.

关键词： Cable-stayed cantilever beam   cable damage   nonlinear vibration   internal resonance  

摘要： Cable-beam structure is a general mechanical model used to study nonlinear dynamics of complex slender structures in the fields of aerospace, bridge and mechanical engineering. To study the effect of cable damage on nonlinear dynamic behaviors of the system, a single-cable cantilever beam model with cable damage is established. The cable damage is described through intensity, extent and position, which is then used to establish coupling damage dynamics through the coupling boundary conditions between the cable and beam. Using Hamilton principle, governing equations of the system are worked out. Ordinary differential equations and their slow dynamic modulation equations are then obtained using Galerkin projection and multi-scale method. Frequency-response and force-response curves are provided for dynamic analysis. For the sake of validating the precision of the outcomes, Runge-Kutta method is employed to solve the original ordinary differential equations directly. Finally, the results reveal that once the cable suffers damage, a new resonance peak may appear in the system, which augments the complexity of the system's nonlinear behavior.

关键词： HIF-1α   STING   allergic asthma   glycolysis   house dust mite   tectorigenin  

摘要： Qufeng Xuanbi Formula (QFXBF), a traditional Chinese medicine prescription used for asthma-like respiratory disorders, has shown anti-asthmatic activity. However, whether it attenuates allergic airway remodeling through innate immune-metabolic regulation remains unknown.

关键词： AMPK   Hypertensive renal disease   Inflammation   PGC-1α   Shenfu decoction   Stigmasterol  

摘要： Shenfu Decoction (SFD) is a traditional famous prescription for replenishing qi and restoring yang. Pharmacological research has confirmed that SFD can warm and tonify yang qi and exerts good therapeutic effects on cardiovascular-related diseases. However, there are no reports on kidney diseases caused by hypertension, and its molecular mechanism needs further exploration.

关键词： Cognitive decline   Elderly   Polyherbal formulation   Traditional Indian medicine  

摘要： Kalyanaka Ghrita (KG) is a classical Ayurvedic polyherbal formulation traditionally indicated for disorders of memory, intellect, and mental well-being. Ayurveda emphasizes individualized therapeutic decision-making, which the N-of-1 trial design aligns with conceptually and methodologically, enabling systematic evaluation of traditional formulations at the single-patient level, where inter-individual variability is central.

关键词： Chalcone   X-ray   Theoretical calculations   Hirshfeld surface analysis   Spectroscopy   NLO  

摘要：

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  The compound was characterized by IR, APT-NMR spectroscopies.
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  The crystal structure of the compound was determined by X-ray analysis.
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  FMO, MEP and Hirshfeld surface analysis for the compound were studied.
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  DFT/B3LYP method was used with the 6-311+G(d,p) basis set.
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  NLO properties were also investigated in this study.

关键词： 1,2,3-triazole   X-ray crystallography, HSA/DFT   NLO   ELF/LOL   Alzheimer's disease   Multi-target docking  

摘要：

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  A novel fluorinated 1,2,3-triazole diarylmethanol (4-FPh-TM) was efficiently synthesised by CuAAC click chemistry, and its molecular structure was unambiguously confirmed by single-crystal X-ray diffraction.
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  Single-crystal X-ray diffraction reveals that 4-FPh-TM packs through a centrosymmetric O–H···N hydrogen-bond dimer, with Hirshfeld surface analysis showing that dispersive C–H and H···H contacts dominate the crystal environment.
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  DFT calculations show that para-fluorine substitution gives 4-FPh-TM the widest HOMO–LUMO gap in its compound series, pointing to high kinetic stability; ELF/LOL analyses pinpoint N15 as the preferred hydrogen-bond acceptor, in full agreement with the crystallographic data.
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  4-FPh-TM shows meaningful non-linear optical activity at the molecular level, well above the urea benchmark, driven by a clear spatial separation between its electron-donor and electron-acceptor regions.
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  Multi-target docking shows that 4-FPh-TM binds competitively at AChE, BuChE, and MAO-B three enzymes central to Alzheimer’s disease progression and meets established drug-likeness criteria, including the ability to cross the blood–brain barrier, identifying it as a promising scaffold for further biological e