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关键词： Compressed sensing   Analysis sparsity   Weighted ℓ1 analysis   Statistical dimension   Prior distributions  

摘要： Recovering signals that are sparse in a transform domain–so-called analysis-sparse vectors–from undersampled measurements is a fundamental problem in compressed sensing. In many practical scenarios, such as imaging, geophysics, and communications, the distribution of transform coefficients is known in advance, providing valuable prior information. Weighted ℓ₁ analysis offers a natural framework to exploit this knowledge, yet a principled method for choosing the weights has remained unsolved. In this work, we propose a distribution-aware framework for weight design. Using convex geometric tools, we establish a computable and nearly tight upper bound on the expected number of Gaussian measurements needed for exact recovery. This bound depends only on two accessible summaries of the prior in the analysis domain: marginal support probabilities and expected signs. Minimizing it yields a near-optimal weight vector that is stable, scale-invariant, and applicable a priori, without iterative tuning. Our theory accurately predicts recovery thresholds and shows how prior knowledge can be converted into provable measurement savings. Extensive simulations confirm substantial reductions in the number of required measurements and reconstruction error relative to unweighted ℓ₁ analysis, with the largest improvements observed for coherent and redundant operators. Overall, this work establishes a rigorous and practical recipe for leveraging distributional priors in analysis-based compressed sensing.

摘要： Pyrite (FeS₂) is the most widely distributed sulfide mineral in nature. Its surface oxidation behavior profoundly affects prevention and control of acid mine drainage (AMD), recovery of mineral resources, and stability of optoelectronic materials. In this study, the oxidation mechanism of the pyrite (1 0 0) surface was systematically investigated based on density functional theory (DFT) calculations. The results show that H₂O adsorbs in molecular form at Fe―Fe hollow site sites, forming weak covalent Fe―O bonds and H…S hydrogen bonds. O₂ molecules preferentially undergo dissociative adsorption at S―S hollow site sites, generating stable S==O double bonds, with electrons transfer characterized by O₂ gaining electrons and S losing electrons. In H₂O-O₂ co-adsorption system, the configuration with undissociated H₂O is more stable, where O₂ acts on the S site and H₂O adsorbs on the Fe site. Under conditions where multiple H₂O and O₂ molecules coexist, sulfur undergoes stepwise oxidation, producing ―SO₂―, SO₃²⁻, and SO₄²⁻ groups, which eventually detach, while iron atoms form Fe₄O₃(OH)₆ (goethite). This reveals the synergistic/competitive mechanism between H₂O and O₂ in multi-molecular environments and verifies the plausibility of the oxidation reaction pathway. This study elucidates the micro-scale mechanism of pyrite (1 0 0) surface under the influence of H₂O and O₂ from atomic and electronic perspectives, providing a theoretical foundation for understanding the oxidation behavior of this mineral.

关键词： CO2 capture   Solvent degradation   BECCS   AMP/PZ   Pilot scale capture  

摘要：

关键词： Density functional theory   Flame retardant materials   Ionic liquids   Magnesium hydroxide nanoparticles  

摘要： In response to the growing demand for environmentally friendly and efficient flame retardants, nano-magnesium hydroxide (nano-MH) has emerged as a promising candidate due to its high thermal stability and smoke suppression properties. However, its practical application is limited by agglomeration and high loading requirements.

关键词： PPV1   Ungulate protoparvovirus1   Epidemiology   Epitope prediction   Docking   Data analysis  

摘要：

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  Positive selection at VP2 residues 320 and 436 suggests adaptive pressure on capsid evolution.
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  VP2 structural modeling revealed lineage-specific conformational changes in exposed regions.
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  Molecular docking showed high-affinity binding of epitopes to SLA alleles.
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  Vaccine strains such as NADL-2 and 27a may not fully cover emerging PPV1 variants.
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  Findings support updated or multi-epitope vaccines against evolving PPV1 lineages.

关键词： Gas sensors   Density functional theory   CdS monolayer   Dissolved gases in oil  

摘要：

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  Detection of dissolved gases in oil using a single-layer Cu_n-CdS (n−1−3) gas sensor.
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  The introduction of Cu_n has improved the electrical conductivity of the single-layer CdS.
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  Cu₂-CdS can be used as an excellent gas-sensitive material for detecting C₂H₂.
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  Cu₃-CdS can be used as an adsorbent material for CO and C₂H₂ at room temperature.

关键词： Myricetin   Liposomal nanoparticles   Diabetes   Testicular function   Oxidative stress  

摘要：

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  MYR-LNPs protect testicular tissue architecture and spermatogenic cell integrity in diabetic rats.
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  Nanoliposomal delivery enhances myricetin bioavailability and therapeutic efficacy compared with the free form.
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  MYR-LNPs restore PI3K/AKT/mTOR/SREBP-1c signaling and mitochondrial function disrupted by diabetes.
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  Treatment mitigates oxidative stress, inflammation, and caspase-dependent apoptosis at tissue and cellular levels.
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  Findings support nanotechnology-based natural interventions to preserve male reproductive health under diabetic conditions.

关键词： Lunar regolith simulants   Particle morphology   Shear strength   X-ray computed tomography  

摘要： Reliable assessment of lunar surface excavation, mobility, and in-situ resource utilization (ISRU) relies on mechanical properties of lunar regolith simulants, which differ substantially in particle morphology and gradation. However, systematic comparative studies on the morphology-mechanical behavior of commonly used simulants remain limited. This study presents a comparative investigation of three representative lunar regolith simulants, LHS-1, LMS-1, and LSP-2, using high-resolution micro-computed tomography (μCT) reconstruction and laboratory direct shear tests. Trainable Weka Segmentation (TWS) and level-set segmentation techniques were used to reconstruct the three-dimensional geometries of the particles, and multiscale shape descriptors were employed to quantify particle morphology. Principal component analysis and Mahalanobis distance evaluation revealed partially overlapping but statistically distinguishable morphological regions among the three simulants. The volume-weighted particle size distribution derived from the reconstructed particle reproduced the relative grading trend obtained from laboratory tests. Direct shear tests were conducted under normal stresses of 24, 48, and 96 kPa, with additional replicate tests used to assess repeatability and uncertainty. The Mohr-Coulomb analysis shows that LSP-2 exhibits the highest internal friction angle, followed by LMS-1 and LHS-1. Semi-quantitative analysis further indicates that the observed differences in shear strength are more reasonably interpreted when particle morphology and gradation are considered together, rather than by morphology alone. These results provide experimental support for numerical modeling and engineering design in future lunar surface operations.

关键词： Sleep stages   Glycemic variability   Type 1 diabetes   Pediatrics   Home sleep test  

摘要： Type 1 diabetes (T1D) may disrupt sleep through several mechanisms, including glycemic variability (GV). Few studies have examined nightly GV and its association with sleep architecture. We examined associations between nocturnal GV and sleep architecture in children and adolescents with T1D during the first 4 h of sleep, when stage N3 is most prominent.

关键词： Alzheimer's disease targets   Cadmium(II) complex   DFT   Dielectric relaxation   In silico studies   Molecular docking  

摘要： A novel cadmium(II) complex, [CdCl₃(HAEP)H₂O]·H₂O (HAEP = 1-(2-aminoethyl)piperazinium), was synthesized and characterized. Single-crystal X-ray diffraction reveals a slightly distorted octahedral geometry around the Cd(II) center, stabilized by a three-dimensional hydrogen-bonding network. DFT calculations indicate high electronic stability and charge-transfer potential. Molecular docking suggests moderate binding affinity to Alzheimer's-related enzymes (AChE, BChE, GR). Impedance spectroscopy reveals non-Debye dielectric relaxation and thermally activated localized conduction regimes associated with the heterogeneous hydrogen-bonded framework formed by protonated HAEP cations, chloride ligands, and coordinated/lattice water molecules. The combined structural, electronic, and in silico analyses highlight the complex's potential in coordination chemistry and bioinorganic applications.