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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：

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  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.

关键词： 2,4,6-Tris(2-pyrimidinyl)-1,3,5-triazine   Crystal structure   Hirshfeld surface   Theoretical calculation   Zinc and cadmium complexes  

摘要： Hydrothermal reactions of 2,4,6-tris(2-pyrimidinyl)-1,3,5-triazine (TPymT) with zinc chloride (ZnCl₂) and with cadmium chloride (CdCl₂) yielded two distinct complexes with divergent ligand reactivity. The reaction with ZnCl₂ induced complete hydrolysis of TPymT to generate the pyrimidine-2-carboxylate anion (2-PmC), affording the 1D zinc coordination polymer [ZnCl(μ-2-PmC)]_n (1) in a good yield of 87.8%. In contrast, the analogous hydrothermal reaction with CdCl₂ proceeded without ligand hydrolysis, leading to the formation of the mononuclear cadmium complex [CdCl₂(TPymT)(H₂O)]·3H₂O (2). Complex 1 was comprehensively characterized by elemental analysis, thermogravimetric analysis (TGA), Fourier-transform infrared (FT-IR) spectroscopy, single crystal X-ray diffraction (SCXRD), powder X-ray diffraction (PXRD), and Hirshfeld surface analysis. Complex 2 was characterize via SCXRD, PXRD and Hirshfeld surface analysis. Solid-state UV–Vis absorption and photoluminescent properties of 1 were further investigated to evaluate its potential optical application prospects. Complementary theoretical calculations were performed to rationalize the metal-dependent TPymT hydrolysis behavior. The synergistic effect of the Zn(II) system's lower molecular stability (narrower HOMO-LUMO gap) and higher electrophilicity promotes ligand dissociation and TPymT hydrolysis. In contrast, Cd(II) exhibits hydrolytic resistance due to its strong nucleophilicity and negative condensed dual descriptor (CDD) value, which collectively stabilize the ligand-metal coordination framework. This work provides valuable insights into the metal-regulated hydrolysis reactivity of TPymT and enriches the coordination chemistry of triazine-pyrimidine hybrid ligands.

关键词： Energy harvesting   Voltage step-up   Boost converter   Charge pump   Thermoelectric   Impedance matching   Maximum power tracking   Power extraction circuit  

摘要：

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  Achieved voltage step-up from 1 mV input to 0.85 V using a boost converter.
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  Demonstrated parasitic impedance matching outperforms traditional matching for 1 mV input.
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  Demonstrated output power above 8 µW from 1 mV input.
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  Promotes wider application of low-cost, reliable thermoelectric modules.

摘要：

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  3-Hexene, 1,1′,''-[ethylidynestris(oxy)]tris-, (3Z, 3′Z,3"Z)-; a safety assessment based on RIFM's criteria.
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  A safety assessment based on 7 human health endpoints plus environmental.
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  All endpoints were cleared using target data, read-across, and/or TTC.

关键词： Analysis model   Signal recovery   ℓ1/ℓ2-regularized minimization   ℓ1/ℓ2norm ratio  

摘要： Currently, in sparse representation of signals, the synthesis model has been extensively studied, while the analysis model receives comparatively less attention. Regarding the sparsity metric, ℓ₁/ℓ₂ norm ratio not only has a sharp approximation to ℓ₀-norm, but also satisfies the scale invariance property inherent to ℓ₀-norm. Motivated by these, this work introduces an analysis model based ℓ₁/ℓ₂-regularized minimization for signal recovery, and conducts theoretical analysis on it under reasonable assumptions that the measurement matrix is full row rank and the observed vector is nonzero. First, under a sufficient condition related to the regularization parameter, we prove that its global minimizer cannot be zero and its solution set is nonempty. Then, we derive an upper bound for any local minimizer of it in terms of ℓ₂-norm. Given that it is nontrivial to directly solve this problem, we relax it by the penalty technique, and provide theoretical analysis for the relaxed version under the aforesaid assumptions, including the nonzero-ness of the global minimizer and the solution existence with the same sufficient condition. Similarly, an upper bound for any local minimizer in terms of ℓ₂-norm is derived. An algorithm for solving the relaxed version is proposed by leveraging alternating minimization and difference-of-convex algorithm, its complexity analysis is also given. Our algorithm is tested via extensive experiments involving numerical examples of one dimensional signal recovery and applications in several image restoration tasks, showing its superiority and competitiveness over some rivals.