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关键词： Charge distribution   Excited state hydrogen bonding interaction   Excited state intramolecular proton transfer   Potential energy surface   Solvent polarity  

摘要： In this work, a systematic investigation was carried out into the excited-state intramolecular double proton transfer (ESDPT) mechanism linked to the 2,7-bis-(5-ethyl-benzooxazol-2-yl)-phenanthrene-1,6-diol (BEPD) molecule dispersed in acetonitrile, dichloromethane and heptane, together with how it responds to solvent polarities. Analysis of structural parameters relevant to hydrogen bonds revealed the reinforcement of intramolecular hydrogen bonding in the excited state among all solvents under investigation, with the O4H5···N6 hydrogen bond exhibiting a more pronounced strengthening effect in the excited state than the O1H2···N3 hydrogen bond. To shed light on the impacts of solvent polarity, we performed a thorough analysis of the core-valence bifurcation (CVB) index, infrared (IR) vibrational spectra and potential energy surfaces (PESs). The results demonstrate that the strength of excited-state hydrogen bonding increases with the reduction of solvent polarity. Furthermore, frontier molecular orbitals (FMOs) analysis was performed to examine charge redistribution during the ESDPT process. Reaction PESs were scanned and transition states (TS) were identified, confirming that BEPD undergoes a stepwise ESDPT mechanism along the O4H5···N6 and then O1H2···N3 hydrogen bond chain in acetonitrile and dichloromethane, while only the excited-state intramolecular singl

关键词： Alzheimer's disease   Mitophagy   Schisandra chinensis(Turcz.)Baill   PINK1/Parkin   MCL-1   Triterpenoids  

摘要： Schisandra chinensis(Turcz.)Baill.in the Schisandraceae has been scientifically validated for its medicinal and dietary properties,with its leaves being edible.Furthermore,the leaves of S.chinensis are abundant in tri-terpenoids that exhibit neuroprotective effects and may possess potential therapeutic value for Alzheimer's disease(AD).HPLC combined with UPLC-Q-TOF-MS was used to characterize the components eluted with 95%EtOH,and a total of 28 triterpenoid compounds were identified.However,the intricate mechanisms underlying the action of SC in treating AD remain incompletely understood.To investigate this,an AD model was established using 3×Tg-AD mice,and the protective effects of SC were assessed through various techniques,including the Morris water maze test,Nissl staining,immunohistochemistry,transmission electron microscopy,and Western blotting.Subsequently,in SH-SY5Y cells induced by CCCP treatment,the protective effect of SC was further verified using JC-1 staining and WB analysis.PINK1/Parkin-dependent mitophagy induced by SC is mediated by SIRT3/FOXO3a and STAT3/TRPML1 signaling,along with MCL-1 activation.This enhancing effect improves cognitive dysfunction and simultaneously alleviates the pathological changes associated with AD.In addition,SC reduced CCCP-induced SH-SY5Y cell death and increased mitophagy-related factors.These results suggest that SC holds significant promise as a therapeutic agent for AD through its ability to promote mitophagy.

关键词： LbV-1   functional verification   resistance genes   sRNA sequencing   transcriptomic profiling  

摘要： Lilium is an economically important genus widely cultivated for ornamental and commercial use. In this study, we report the identification and characterization of a novel mitovirus, designated Lily Bulb Virus-1 (LbV-1), detected in commercial lily bulb stocks. This virus represents a previously uncharacterized member of the mitochondrial RNA virus group associated with lily crops. A survey of 50 commercially cultivated lily bulbs, including Lilium longiflorum varieties, revealed LbV-1 infection in a single cultivar, indicating a low but detectable incidence under the tested conditions. Although infected plants exhibited no visible symptoms during in vitro cultivation, the presence of LbV-1 was confirmed through PCR amplification, small RNA (sRNA) sequencing, transmission electron microscopy (TEM), and mechanical inoculation assays. A total of 9122,220 unique sRNA reads were identified, with 21–22 nt virus-derived small RNAs mapping to the LbV-1 genome, supporting active host–virus interaction. Additionally, transcriptome-based analyses indicated efficient bulb-mediated transmission, with an infection rate of up to 45% in progeny plants. Comparative transcriptomic analysis of infected and healthy bulbs yielded over 30 million high-quality reads, resulting in the assembly of 3671,77 transcripts and 168,004 unigenes with an average length of 1445 bp. Differential expression analysis identified eight candidate genes (Li-PCP, Li-DUF, Li-UBD, Li-FRC, Li-CF, Li-APD, Li1-UN, and Li7-UN) that were significantly upregulated in response to LbV-1 infection and validated across three developmental stages using RT-qPCR. Functional analysis demonstrated that seven of these genes enhanced viral resistance when expressed in susceptible lily plants. These findings provide new insights into the molecular biology, transmission dynamics, and host defense responses associated with LbV-1. Th

关键词： Alcohols   Liquid-liquid equilibrium   NRTL   Sulfuric acid  

摘要： Liquid-liquid equilibrium (LLE) data were obtained for water + sulfuric acid + {1-butanol, isopentanol, 1-pentanol, or 1-heptanol} ternary systems at temperatures of 298.2 K and 323.2 K under atmospheric pressure (P ≈ 101.9 kPa). The immiscibility regions were experimentally identified through binodal curves using the cloud point method. Tie-line data were determined through direct sulfuric acid composition measurements and mass fraction calibration curves. Based on these data, distribution coefficients, alcohol selectivity and extraction percentage were calculated to evaluate the influence of different alcohols and temperature on sulfuric acid separation potential. Experimental LLE data were correlated using the Non-Random Two-Liquid model, presenting a root-mean-square deviation equal to 1.1768 % for all studied systems. The model also allowed the estimation of binodal curves and plait points. These results contribute to the understanding and optimization of solvent extraction processes involving sulfuric acid recovery in industrial water streams.

关键词： Approximation of multivariate functions   Trigonometric polynomials   Rank-1 lattice rule   Weighted Korobov space   Hyperbolic cross  

摘要： This paper studies the multivariate approximation of functions in weighted Korobov spaces using multiple rank-1 lattice rules. It has been shown by Kämmerer and Volkmer (2019) that algorithms based on multiple rank-1 lattices achieve the optimal convergence rate for the $L_{\infty }$ error in Wiener-type spaces, up to logarithmic factors. While this result was translated to weighted Korobov spaces in the recent monograph by Dick, Kritzer, and Pillichshammer (2022), the analysis requires the smoothness parameter α to be greater than 1 and is restricted to product weights. In this paper, we extend this result for multiple rank-1 lattice-based algorithms to the case where $1/2<\alpha \le 1$ and for general weights, covering a broader range of periodic functions with low smoothness and general relative importance of variables. We also provide a summability condition on the weights to ensure strong polynomial tractability for any $\alpha >1/2$. Furthermore, by incorporating random shifts into multiple rank-1 lattice-based algorithms, we prove that the resulting randomized algorithm achieves a nearly optimal convergence rate in terms of the worst-case root mean squared $L_2$ error, while retaining the same tractability property.

摘要： Fiber combiners (FCs), which fuse multiple input fibers into a common output port, offer a strategic approach to scaling laser power and expanding spectral coverage, especially in the mid- and long-wave infrared (MWIR/LWIR) bands where individual laser performance is often limited. Chalcogenide glasses serve as ideal materials for such combiners due to their broad infrared transparency and superior thermal stability. However, fabricating FCs capable of withstanding high laser power while maintaining high beam quality remains challenging, particularly when targeting wavelengths beyond 8 μm. Here, we present the first demonstration of a high-beam-quality 4 × 1 fiber combiner based on Ge-As-Se glass, designed for MWIR/LWIR laser combination. The device integrates four few-mode input fibers (50 μm core) into a multimode output fiber (150 μm core) via an optimized taper geometry (transition region length L_t= ∼10 mm, taper ratio R = ∼4.6). The fabricated FC had a total length of ∼ 60 cm. At 8.3 μm, the combiner achieved a port transmission efficiency of 81.6% and maintained an output beam quality of M² = 3.62 under four-port excitation. Power combining at 2.1 μm yielded 6.5 W from four 3.0-W inputs, corresponding to a power-combining efficiency of 82.7%. Furthermore, the combiner successfully synthesized a broadband spectrum by integrating discrete laser lines at 3.2, 4.6, 4.9, and 8.3 μm. These results establish the few-mode Ge-As-Se fiber combiner as a promising platform that delivers both high-power combination and high beam quality across the MWIR and LWIR bands for advanced infrared photonic systems.

关键词： Parkinson's disease   SGK1   α-synuclein   SW480   SH-SY5Y  

摘要：

• •
  Recombinant SGK1-myc was expressed in tobacco and extracted for Parkinson's models.
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  SGK1 enhances tyrosine hydroxylase (TH) in the substantia nigra and striatum in PD.
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  SGK1 modulates Na⁺/K⁺ pump and gut function, showing promise for early-onset PD.
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  SGK1-myc treatment increases SGK1 expression and improves PD-associated pathology.

关键词： 4,4′,6,6′-tetra(azido)hydrazo-1,3,5-triazine   Adiabatic time-to-explosion   Combustion   High-nitrogen compounds   Thermal safety  

摘要： High-nitrogen compounds are promising energetic materials due to their high enthalpy of formation (${\Delta }_{\mathrm{f}}{H}_{\mathrm{m}}^{\theta }$) and environmentally friendly combustion products. However, the thermal decomposition kinetics, thermal safety and combustion behavior of 4,4′,6,6′-tetra(azido)hydrazo-1,3,5-triazine (TAHT) have not yet been systematically clarified.

摘要： The authors regret that the funding information was inadvertently omitted from the published version of the article. The following funding statement should be included: "This work has been supported by grant PID2023-148214OB-C21 funded by MICIU/AEI/10.13039/501100011033 and is part of the project TRUST Lab, R&D&I Laboratory in Cybersecurity, Privacy, and Secure Communications, financed by European Union NextGeneration-EU, the Recovery Plan, Transformation and Resilience, through INCIBE.". © 2026 The Author(s). Published by Elsevier B.V. This is an open access article under the CC BY-NC license. http://***/licenses/by-nc/4.0/

关键词： Hirota-Maccari system   Lyapunov exponent   Melnikov theory   Modulational instability   Stochastic nonlinear dynamics  

摘要： This paper investigates a stochastic (2+1)-dimensional Hirota-Maccari system under multiplicative noise modeled via Stratonovich calculus, emphasizing novel analytical and numerical methodologies. A noise-adaptive traveling-wave ansatz reduces the stochastic PDEs to deterministic second-order nonlinear oscillators using stochastic averaging techniques. Employing Hamiltonian formalism and phase-plane analysis, we systematically classify nonlinear wave solutions including periodic, bright solitons, and kink-type structures. We rigorously derive a new modulational instability dispersion relation, capturing intricate interactions between nonlocal coupling, higher-order dispersion, and noise-induced stabilization effects. Using Melnikov theory complemented by numerical Lyapunov exponent calculations, we demonstrate both homoclinic and heteroclinic chaos, providing compelling analytical and numerical evidence of chaotic dynamics. Numerical simulations confirm theoretical predictions, illustrating noise-induced broadening, amplitude fluctuations, and altered wave stability. The presented integrative approach significantly advances understanding of stochastic nonlinear wave phenomena, offering robust methodologies for analyzing complex wave dynamics under realistic noisy conditions.