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关键词： Debye-Waller factor   Einstein temperature   SAXS   SiGe   TLZ growth   XAS  

摘要： We investigate local vibrational parameters in bulk single-crystalline Si_1-xGe_x grown by the traveling liquidus-zone method (x = 0.32, 0.45, 0.71, 0.80, and 0.93). Temperature-dependent Ge K-edge X-ray absorption spectroscopy (XAS) was performed in transmission mode. XAS spectra were obtained over the entire temperature range without oxide-related white-line features, and fine structures attributable to multiple-scattering in crystalline Si_1-xGe_x were consistently observed. The k³-weighted extended X-ray absorption fine structure oscillations were analysed by first-shell fitting to extract Debye-Waller factors for Ge-Ge and Ge-Si bonds. By Einstein modelling, we determined the Einstein temperature (${\Theta }_E$) and static disorder (${\sigma }_s^2$) components. The ${\Theta }_E$ are nearly composition independent, with average values of ∼371 K for Ge-Ge and ∼569 K for Ge-Si, whereas the ${\sigma }_s^2$ for Ge-Si exhibits a pronounced maximum at x = 0.45. Complementary SAXS for x = 0.45 shows low-q excess scattering that can be described by a Debye-Bueche model with a correlation length of ∼8.8 nm, providing a characteristic length scale for discussing nanometre-scale inhomogeneity. These results highlight a marked contrast between heteroatomic and homoatomic bonds in the development of static disorder in strain-free bulk Si_1-x

关键词： Heusler alloys   Density functional theory   Half-metallicity   Spin polarization   Electronic correlations  

摘要： Fe${}_{2(1-x)}$Co${}_{2x}$MnSi Heusler alloys are widely discussed as candidates for spintronic applications, but the robustness of their half-metallic character across the Fe$\to$Co substitution series remains unresolved. Here, we investigate the full series ($x=0,1/8,\dots ,1$) by first-principles calculations, combining configurational screening with density functional theory at the generalized gradient approximation (GGA), GGA+$U$, and selected HSE06 levels. We find that standard GGA tends to overestimate ideal half-metallicity, whereas GGA+$U$ and HSE06 consistently show that most compositions are better described as nearly half-metallic systems with a narrow minority-spin pseudogap at the Fermi level. Accordingly, Fe${}_2$MnSi is not a qualitatively distinct endpoint, but part of the same general nearly half-metallic regime that characterizes most compositions in the series. This pseudogap evolves non-monotonically with Co content and disappears in Fe_1.75Co_0.25MnSi and Fe_1.25

关键词： Atmospheric plasma spraying   High-entropy ceramic coating   Infrared emissivity  

摘要： To address the demand for high-temperature infrared stealth, a novel high-entropy rare-earth disilicate (Lu_1/6Yb_1/6Sc_1/6Er_1/6Y_1/6Ho_1/6)₂Si₂O₇ ((6RE_1/6)₂Si₂O₇) coating was fabricated via atmospheric plasma spraying. The coating exhibited a single-phase monoclinic structure with uniform element distribution. It demonstrated low infrared emissivity in the 3−5 μm band, with values of 0.497 at room temperature and 0.479 at 400 °C. This low emissivity is attributed to the increased charge carrier concentration resulting from oxygen vacancies, as confirmed by X ray photoelectron spectroscopy (XPS) analysis. Furthermore, the coating achieved a low thermal conductivity of 0.51 W m⁻¹ K⁻¹ at 1173 K, benefiting from severe phonon scattering caused by the high-entropy composition. The coating also possessed a good bonding strength of 31.98 MPa. This work demonstrates that the high-entropy strategy is effective in developing silicate coatings with synergistic low emissivity and low thermal conductivity for advanced infrared stealth applications.

关键词： Abdominal aortic aneurysm   Acute intestinal ischemia   Aortoiliac occlusive disease   Glucagon-like peptide-1  

摘要： Acute intestinal ischemia is a severe postoperative complication of abdominal aortic surgery, and delayed diagnosis markedly limits therapeutic options. At present, no reliable biochemical marker for early detection is available. This study assesses whether perioperative changes in glucagon-like peptide-1 (GLP-1) may serve as an early biomarker of postoperative intestinal ischemia.

关键词： ML   Machine learning   DCW   dry cell weight   3D   three-dimensional   MD   molecular dynamics   STY   space-time yield   BVMO-4-M5   variant BVMO-4-H116N-M497E-L230N-V17I-Q526V   ee   enantiomeric excess   BVMO   Baeyer-villiger monooxygenase   CHMO   cyclohexanone monooxygenase   NADPH   nicotinamide adenine dinucleotide phosphate reduced form   FDH   formate dehydrogenase   kcat/Km   catalytic efficiency   Indoxacarb precursor   Rational design   Catalytic activity   Biocatalysis  

摘要：

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  Engineered a phenylacetone monooxygenase via integrated MD simulations and machine learning.
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  The quintuple variant exhibited a 4.1-fold increase in catalytic activity.
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  Achieved preparative-scale synthesis (101.7 g/L) of a key chiral insecticide precursor.
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  The biocatalytic process afforded high enantiomeric excess (>98.2%) and space-time yield (203.4 g/(L·d)).

关键词： Choroidal thickness   Neovascular age-related macular degeneration   Predictive factors   Submacular hemorrhage   Visual outcome  

摘要： To identify clinical and imaging predictors of 12-month visual outcome in patients with fovea-involving submacular hemorrhage (SMH) due to neovascular age-related macular degeneration (nAMD) and polypoidal choroidal vasculopathy (PCV).

关键词： 4-hydroxy-tamoxifen   Calpain-2   Neuropilin-1   Stemness   Tamoxifen   Triple-negative breast cancer   β-catenin  

摘要： Reactivating functional estrogen receptor alpha (ERα) expression represents a promising strategy for tamoxifen (TAM)-based endocrine therapy in triple-negative breast cancer (TNBC). However, TAM and its metabolites may exert potential oncogenic effects, which could compromise TAM efficacy in TNBC. Here, we report that low-dose 4-hydroxytamoxifen (4-OHT), an active metabolite of TAM, enhances stemness in TNBC cells via the Neuropilin-1 (NRP-1)/Calpain-2 (CAPN2)/β-catenin axis. Mechanistically, 4-OHT stimulates CAPN2 activation by promoting its membrane localization, increasing substrate cleavage, and inducing degradation of its endogenous inhibitor calpastatin. Activated CAPN2 suppresses ubiquitin-mediated degradation of β-catenin, leading to elevated β-catenin stability and intracellular accumulation. This enhances β-catenin transcriptional activity and ultimately promotes stemness in TNBC cells. Kaplan–Meier survival analysis showed that high NRP1 expression correlates with poorer overall survival in breast cancer patients undergoing endocrine therapy. Moreover, 4-OHT triggers Ca²⁺ release and ERK phosphorylation in TNBC cells through the NRP-1/PLC-γ1 pathway, thereby activating CAPN2. Finally, we demonstrate that the NRP-1 inhibitor EG00229 sensitizes ERα-re-expressing TNBC cells to TAM treatment. Our study uncovers a molecular mechanism by which 4-OHT promotes TNBC stemness via the NRP-1/CAPN2/β-catenin signaling cascade. Targeting NRP-1 may serve as a valuable strategy to improve TAM efficacy in ERα-re-expressing TNBC.

关键词： MEK inhibitors   Mirdametinib   Neurofibromatosis-1   Pain   Pain interference   Patient-reported outcomes   Plexiform Neurofibroma   Selumetinib  

摘要： Plexiform neurofibromas (PN) associated with neurofibromatosis type 1 (NF1) are frequently associated with substantial pain burden and functional impairment. Mitogen-activated protein kinase kinase (MEK) inhibitors have demonstrated efficacy in tumor control; however, their impact on patient-reported pain outcomes remains incompletely characterized. We conducted a systematic review and meta-analysis to evaluate the effect of MEK inhibitors on pain intensity, pain interference, and clinically meaningful pain improvement in patients with NF1-associated PN.