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关键词： Valence bands  

摘要： Manganese-doped tin telluride, Sn_1-xMn_xTe, initially investigated as diluted magnetic semiconductor, has recently attracted considerable attention as a prospective thermoelectric material. The introduction of manganese was found to modify the valence band electronic structure, resulting in an improvement in the Seebeck coefficient and thus, the figure of merit (ZT). In the paper, we present a synchrotron radiation study of the electronic band structure of Sn_0.9Mn_0.1Te by resonant photoemission. The contribution of the Mn3d electrons to the valence band (VB), calculated as the difference between the Energy Distribution Curves (EDCs) taken at the maximum and minimum of the Fano resonance for the Mn3p → Mn3d absorption threshold, shows a Mn3d related contribution at the VB edge, a dominant maximum at 4 eV, as well as a wide satellite structure between 7 and 11 eV. Comparison with undoped SnTe reveals that the introduction of Mn leads to a strong renormalization of the deep valence band states, Sn5s and Te5s, which through their hybridization with the Sn5p and Te5p states influences the shape of the valence band edge and electron effective mass and therefore the ZT value.

关键词： SD-R   Cross-protection   Cellular immunity   Humoral immunity  

摘要：

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  In the initial phase of vaccine immunization, SD-R exhibits a more robust induction of antigen-specific Th cell and CTL activation, along with a significantly enhanced IFN-γ-secreting cell response, compared to the commercially available vaccines CH-1R and HuN4-F112.
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  SD-R is able to elicit specific T-cell-mediated immune responses upon stimulation with diverse PRRSV-2 strains, whereas the neutralizing capacity of early cross-reactive antibodies varies markedly across different viral strains. In the early phase of SD-R-induced immunity, T cell-mediated immunity is closely associated with cross-protection, while humoral immunity acts in a supportive capacity.

关键词： Hydrogen storage   Clathrate hydrate   Hydrate promoter  

摘要：

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  An optimal T1 configuration is identified for H₂ + DIOX sII hydrate.
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  The T1 configuration yields the hydrogen storage capacity of 4.56 wt%.
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  The T1 configuration exhibits high stability at 10–30 MPa and 260–285 K.
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  DIOX acts as a highly efficient dual-function hydrate promoter.

关键词： 青少年特发性脊柱侧凸   Lenke分型   骶股耻骨角   脊柱-骨盆参数   相关性分析   脊柱-骨盆平衡  

摘要： 背景:骶股耻骨角作为骨盆倾斜角的冠状位替代指标,它在青少年特发性脊柱侧凸不同Lenke分型中的关联特征尚未明确,这限制了骶股耻骨角在分型化评估中的临床应用。目的:探讨Lenke1、5、6型青少年特发性脊柱侧凸患者骶股耻骨角与脊柱-骨盆参数(骨盆入射角、骨盆倾斜角、骶骨倾斜角、腰椎前凸角、胸椎后凸角及Cobb角)的相关性,建立分型特异性回归模型。方法:回顾性分析191例青少年特发性脊柱侧凸患者的临床及影像学资料,其中Lenke1型60例、Lenke5型65例、Lenke6型66例。采用Pearson或Spearman分析各分型患者左右侧骶股耻骨角与骨盆入射角、骨盆倾斜角、骶骨倾斜角、腰椎前凸角、胸椎后凸角、Cobb角、矢状面轴向偏距的相关性,对有统计学意义的参数进行一元线性回归分析,构建线性回归模型。结果与结论:①在Lenke1型青少年特发性脊柱侧凸患者中,右侧骶股耻骨角与骨盆倾斜角呈显著负相关(r=-0.366,P=0.028),左右侧骶股耻骨角与腰椎前凸角呈显著正相关(r=0.429,P=0.007;r=0.460,P=0.007)。在Lenke5型青少年特发性脊柱侧凸患者中,左右侧骶股耻骨角与腰椎前凸角呈显著正相关(r=0.415,P=0.007;r=0.400,P=0.007)。在Lenke6型青少年特发性脊柱侧凸患者中,左右侧骶股耻骨角与骨盆倾斜角呈显著负相关(r=-0.385,P=0.007;r=-0.376,P=0.014)。一元回归模型量化了上述关联(R^(2)=0.13-0.21),其中Lenke5型青少年特发性脊柱侧凸患者骶股耻骨角与腰椎前凸角的回归方程斜率最大(0.85-0.89),Lenke6型青少年特发性脊柱侧凸患者骶股耻骨角与骨盆倾斜角的回归方程斜率为-0.52至-0.54。②结果表明,Lenke1、5、6型青少年特发性脊柱侧凸患者骶股耻骨角与脊柱-骨盆参数的关联存在明确分型特异性,Lenke1、5型以骶股耻骨角与腰椎前凸角正向关联为主,Lenke6型以骶股耻骨角与骨盆倾斜角双侧负关联为特征。

关键词： Cation vacancies   Electrochemical reaction   Metal ion doping   Positron annihilation   VO2(B)  

摘要： Iron-doped VO₂ nanorods (V_1-xFe_xO₂) containing oxygen and cation vacancies were successfully fabricated via a simple one-step hydrothermal technique. XRD characterization shows that the lattice contraction arises from metal cation doping. When evaluate as an electrode material, these iron-doped VO₂ nanorods exhibit improved energy storage performance compared with pure VO₂. Specifically, the specific capacitance of the V_1-xFe_xO₂ (x = 0.005) sample is 47.2 mAh/g at 0.1 A/g, and the V_1-xFe_xO₂ (x = 0.005) also delivers the highest specific capacity, maintaining 81.85% of its capacitance retention after 1000 cycles at 1.0 A/g. The mechanism underlying the enhancement of electrochemical performance was investigated using XPS spectra and positron lifetime annihilation spectroscopy (PLAS). The results suggest that Fe³⁺ doping increases the concentrations of both oxygen and cation vacancies, which contributes to the improvement of electrochemical performance. This work shows that the doping of iron ions with smaller radius and lower valence state can introduce oxygen vacancies as well as cation vacancies, thus significantly improve the electrochemical performance of VO₂. The study demonstrates that cation doping represents a viable strategy for optimizing the electrochemical performance of electrode materials.

关键词： Fluorides   LiYF4 ceramics   Microwave dielectric properties  

摘要： Non-stoichiometric Li_(1+x)YF_(4+x) (x = 0.00, 0.03, 0.05, 0.07) ceramics were synthesized via the solid-state reaction route to explore their structural evolution, densification behavior, and microwave/millimeter-wave dielectric performance. By compensating LiF volatilization during sintering, the formation of the Y₆O₅F₈ secondary phase was effectively suppressed. X-ray diffraction and Rietveld refinement confirmed the tetragonal scheelite-type LiYF₄ phase (space group I41/a), with the minimum secondary-phase content (0.58%) achieved at x = 0.03. The ceramics exhibited excellent densification, attaining a maximum relative density of 97% at a low sintering temperature of 700 °C—substantially reduced compared with unary fluoride YF₃. The optimized composition (x = 0.03) demonstrated superior dielectric properties: ε_r = 9.4, Qf = 16,234 GHz at ∼22 GHz, and τ_f = –54.2 ppm/°C. Infrared reflectance spectra revealed an intrinsic high Qf value of 126,390 GHz, indicating great potential of improvement of Qf value via further suppressing the extrinsic dielectric losses. These findings establish Li_(1+x)YF_(4+x) ceramics as promising low-ε_r, low-loss candidates for high-frequency microwave and millimeter-wave communication components.

关键词： Collision-induced absorption   Carbon dioxide   H2   Atmospheric composition   Binary absorption coefficients  

摘要： The collision-induced absorption (CIA) of a H2-CO2 mixture has been studied in the [3907, 4770] cm-1 spectral range for temperatures ranging from 241 to 498 K. The experiments were based on the use of a new high-resolution Fourier spectrometer coupled with an atmospheric simulation chamber. Binary absorption coefficients (BACs) were measured for the first time in the [4033, 4730] cm-1 spectral range at temperatures other than room temperature and are provided in tabular form. At room temperature, the results are compared with existing experimental data and theoretical coefficients, while for the other temperatures, only theoretical values are available. For all considered temperatures, we computed the theoretical integrated band intensity for the experimental BACs and the semi-empirical models. The calculations have been made over the reduced [4033, 4730] cm-1 spectral range, and the entire band, in order to explore the bias induced by using a restricted spectral region. Furthermore, the H2-CO2 BACs were compared with the previously measured H2-H2 and H2-He data. We observed an overall higher absorption of the H2-CO2 BACs, with scaling factors ranging from six to sixteen with respect to the H2-H2 BACs, and from nine to twenty-seven for the H2-He case, depending on the spectral region. Finally, we used an empirical approach, to parametrize the BACs using an exponential profile as a function of temperature, using a series of wavenumber-dependent coefficients, an. These coefficients allow to interpolate the BACs in the temperature range covered by the measurements.

关键词： Myopia   Scleral remodeling   Hypoxia   Glycolysis   Lactate   Autophagy  

摘要：

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  Hypoxia drives HIF-1α-dependent glycolytic rewiring in scleral fibroblasts.
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  CQ flux assays support enhanced autophagic flux under hypoxia and lactate.
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  PH controls separate lactate-associated effects from extracellular acidification.
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  GNE-140 add-back supports a downstream LDH/lactate branch in remodeling.
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  Subconjunctival 2DG lowers scleral lactate and attenuates FDM progression.

关键词： Rare-earth orthochromite   Perovskite A-site substitution   Vibrational property   Magnetic property   Optical bandgap  

摘要： The (Nd_1-xSm_x)CrO₃ (0 ≤ x ≤ 1) solid solution was synthesized by conventional solid-state reactions. X-ray powder diffraction data Rietveld refinements confirm that each compound could be described in the orthorhombic space group Pnma. Successive replacement of Nd³⁺ by smaller Sm³⁺ cations induces an anisotropic lattice response, characterized by contraction of the b- and c-lattice parameters with a slight expansion in the a-direction, resulting in an overall linear decrease of the unit cell volume. Structure analysis reveals that lattice accommodation occurs predominantly through octahedral tilting and oxygen displacement rather than a significant compression of the Cr–O bond. This effect is evidenced by the nearly invariant CrO₆ octahedral volume and quadratic elongation across the solid solution. The CrO₆ octahedra exhibit higher tilting for the Sm-rich compositions, highlighting how the perovskite-type A-site substitution reduces the tolerance factor. Temperature-dependent magnetization reveals long-range antiferromagnetic ordering of the Cr³⁺ sublattice. The magnetic response of the intermediate compositions (0 < x < 1) exhibits two distinct anomalies near the closely spaced Néel temperatures of the endmembers. The negative Curie-Weiss temperatures obtained from the paramagnetic regime further support the dominant antiferromagnetic interactions. The absolute values of the Curie–Weiss temperatures increase with increasing Sm content, consistent with systematic changes in the Cr–O–Cr superexchange pathway caused by enhanced octahedral tilting. The spin reorientation transition observed for the Nd-rich compositions is gradually suppressed with increasing Sm substitution. In the same way, Raman as well as FTIR spectroscopic data demonstrate systematic hardening of the optical

关键词： Almost affinely disjoint subspace   Asymptotically optimal families   Block matrices   Determinant   Partial spread  

摘要： Let ${\mathbb{F}}_q$ denote the finite field of size q and ${\mathbb{F}}_q^n$ denote the standard vector space over ${\mathbb{F}}_q$. A collection of k-dimensional subspaces of ${\mathbb{F}}_q^n$ with pairwise trivial intersection is called a partial k-spread. A partial k-spread is called an almost affinely disjoint (AAD) subspace family if each affine coset of a member of this family intersects at most L subspaces in the family. In particular, if $n=2k+1$, the family is called L-nice.