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关键词： Sustainable energy carrier   Energy storage   Metal combustion   Silicon  

摘要：

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  Stable silicon powder ignition at 1300 °C in a drop tube reactor for minutes.
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  Finer particles oxidise faster, raising local temperature and NOx levels.
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  Bowl feeder ensures homogeneous, clump-free fuel dosing.
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  Measurements of temperature and electric heater indicate an exothermic reaction.
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  SiO₂ layer and agglomeration affect the progress of oxidation.

关键词： Narcolepsy   Cataplexy   Twins   Environmental factors   Child  

摘要： Narcolepsy type 1 (NT1) is a chronic and non-progressive neurological disorder that frequently arises in childhood. NT1 is characterized by loss of physiological boundaries between wakefulness and sleep, excessive daytime sleepiness, cataplexy, sleep paralysis, and hypnagogic or hypnopompic hallucinations. Current evidence supports a complex multifactorial model in which NT1 results from the interplay of immune-related genetic predisposition and environmental triggers, leading to immune-mediated destruction or dysfunction of hypocretin-producing neurons. Accordingly, we aimed to provide an updated review of the evidence regarding the role of environmental factors in the etiopathogenesis of NT1.

关键词： Driving mechanisms   Farmland abandonment   Interaction effects   Random forest   SHAP  

摘要： Reducing farmland abandonment is essential for protecting farmland resources and ensuring national food security. The driving mechanisms of farmland abandonment in China at the 1-km grid scale remain insufficiently understood. In this study, a composite theoretical framework integrating natural factors, socioeconomic factors, and cultivation conditions was developed to explain farmland abandonment at the grid scale. Fifteen driving variables, together with a 1-km gridded dataset of farmland abandonment ratio (the proportion of abandoned farmland relative to the total farmland area), were modelled using random forest models. The SHAPley additive explanations algorithm was applied to quantify both the individual effects and interaction effects. The results revealed that in 2019, the overall farmland abandonment ratio in China was 4.49%, with higher rates observed in mountainous areas (6.26%) than in the plains (2.22%). Stable hotspots of farmland abandonment emerged in the agro‑pastoral transition zone between the northern arid and semiarid regions and the Loess Plateau, in the southeastern coastal region, in the southwestern mountainous region, and around the Beijing–Tianjin–Hebei urban agglomeration. Distinct driving mechanisms of farmland abandonment were observed between plains and mountainous areas. Increased farmland density mitigated abandonment risk across both terrains by strengthening large‑scale farming and organizational structure. In plains, farmland abandonment was governed mainly by labour, location, and organizational structure. Engineering improvements and institutional support weakened the effects of climatic and topographic factors. The influence of ageing was both stage-specific and bidirectional. In mountainous areas, farmland abandonment was driven mainly by strong coupling among climatic conditions, topography, and service accessibility. The effects of climatic conditions were amplified by their interactions with slope and altitude, resulting in

关键词： Bandgap reference   Curvature compensation   Sub-1 ppm/°C   Trimming  

摘要： This paper presents a curvature-compensated bandgap reference (BGR) that achieves a 0.92-ppm/°C temperature coefficient (TC) through a modified design approach derived from the conventional Banba BGR architecture. The proposed topology introduces an additional complementary to absolute-temperature (CTAT) component derived from the MOSFET gate-source voltage (V_GS) biased in the subthreshold region, in addition to the conventional CTAT component generated by V_BE. The combination of these two CTAT components effectively compensates the nonlinear temperature dependence of V_BE. By properly scaling a proportional to absolute temperature (PTAT) component extracted from ∆V_BE together with the CTAT components derived from V_BE and V_GS, the overall temperature dependence of the reference voltage is significantly reduced, resulting in a near-zero TC. The proposed structure also enables independent trimming of the output voltage level and the TC. Post-layout PVT simulations and a 500-run Monte Carlo analysis demonstrate an average reference voltage of approximately 600 mV and an average TC of 0.92 ppm/°C. The proposed BGR further achieves a 0.003%/V LS over a 1–2 V supply with a power consumption of 9.1 μW.

关键词： Shape memory polymers   Self-healing   Epoxidized trans-1,4-polyisoprene (ETPI)  

摘要：

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  A composite material exhibiting self-healing capability, excellent mechanical properties, and shape memory effect has been prepared.
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  The repair mechanism relies on disulfide bond exchange reactions and the shape memory effect.
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  The thermal stability of the samples improved after recycling.

关键词： Hyponatremia   Del-1   Osteopenia   Muscle wasting  

摘要：

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  Hyponatremia decreased skeletal muscle and circulating Del-1 levels in mice.
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  Low sodium concentration reduced Del-1 expression in mouse muscle cells.
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  Reduced muscle Del-1 levels are related to bone loss in hyponatremic mice.
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  Del-1, as a myokine, is involved in the hyponatremia-induced bone loss in mice.

摘要： Modern wireless communication systems demand microwave dielectric ceramics with stable dielectric characteristics and high material reliability for efficient device performance. In this work, Ca-substituted zinc aluminate nanoparticles, Zn_1−xAl₂O₄Ca_x (x = 0.00, 0.15, 0.35, and 0.55), were synthesized via the sol–gel method and investigated for C-band microstrip patch antenna applications. X-ray diffraction confirmed a single-phase cubic spinel structure, with crystallite size increasing from 8.2 to 10.6 nm as Ca content increased. TEM analysis showed spherical nanoparticles with sizes decreasing from 17 to 15 nm (ZAC_0.00–ZAC_0.55), and HRTEM revealed lattice spacings of 0.28–0.46 nm. Dielectric measurements indicated that ZAC_0.55 exhibits improved properties, with a dielectric permittivity of 21.6, dielectric loss of 0.020, and AC conductivity of 4.69 μΩ⁻¹cm⁻¹. Microstrip patch antennas fabricated using these materials showed that the ZAC_0.55-based antenna achieved a return loss of −20.06 dB at 6.68 GHz with an impedance bandwidth of 840 MHz. These results demonstrate that Ca doping effectively tailors the dielectric properties of zinc aluminate, leading to enhanced antenna performance for C-band applications.

关键词： Argon   Broadening coefficients   Dicke narrowing   Dual-comb spectroscopy   High-resolution mid-infrared spectroscopy   Speed-dependence   Water vapor  

摘要： Absorption spectra of water vapor perturbed by argon were recorded using a high-resolution dual-comb spectrometer operating in the 1615–1675 cm^-1 spectral region. 35 lines mostly belonging to the P, Q and R-branches of the ${\nu }_2$ band of H₂¹⁶O were studied at room temperature with total pressures ranging from 11 to 694 mbar. The collisional broadening and shifting coefficients, along their speed-dependencies and the collisional Dicke narrowing parameters were determined by fitting the Voigt, Rautian, speed-dependent Voigt and speed-dependent Rautian profiles in a multi-spectrum procedure. To our knowledge, this is the first time that the line-shape parameters of this molecular system are investigated in this spectral region. Our results were compared to the few available literature for various absorption bands, and the agreement was found to be quite variable, most likely due to vibrational dependencies of these parameters.

关键词： Tocotrienol   Atherosclerosis   AutoDock Vina   GNINA   Endothelial adhesion biomarker   Molecular dynamics simulation  

摘要：

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  β-tocotrienol showed the strongest binding affinities to VCAM-1 in AutoDock Vina
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  α-tocotrienol displayed the highest binding affinity to E-selectin and ICAM-1 AutoDock Vina.
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  GNINA exhibited the strongest binding affinity to ICAM-1 protein for β-tocotrienol isomer.
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  VCAM-1 structural limits may affect AI-assisted docking and future flexible-docking studies. VCAM-1 structural limits may affect AI-assisted docking and future flexible-docking studies.
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  Molecular simulation identified GLU87 and ASP178 as key residues stabilising β-tocotrienol -VCAM-1 forming hydrogen bonding.

关键词： cardiovascular disease risk   dyslipidemia   inflammation   prevention   sex differences   type 1 diabetes  

摘要： Women with type 1 diabetes experience a greater diabetes-related increase in cardiovascular disease and mortality risk than men. This study aims to examine early sex-related differences in cardiovascular disease risk factors among youths with type 1 diabetes.