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The effect of the heating/cooling rates of nonisothermal aging (NIA) on microstructure and mechanical properties of 2050 Al–Li alloy are investigated. The 2050 Al–Li alloy is first solid solutioned and predeformed and then heated from 130 to 220 °C at different rates of 20, 30 °C h−1, or 40 °C h−1 and then cooled to 150 °C. The results show that the mechanical properties of the alloy subjected to NIA treatment can be improved by adjusting the heating and cooling rate. When the heating and cooling rate is 30 °C h−1, the alloy achieves the best mechanical properties; the hardness, ultimate tensile strength (UTS), yield strength (YS), and elongation are 182.9 HV, 597, 571 MPa, and 9.6%, respectively. With the decrease of heating (or cooling) rate of NIA, the diameter and thickness of the T1 precipitate increase and the volume fraction decreases, resulting in the variation in mechanical properties. Therefore, herein, premier precipitation behavior and improved mechanical properties are both achieved by modifying the heating and cooling rate of NIA; the effect of the heating/cooling rate of NIA on the microstructure evolution of 2050 Al–Li alloy is revealed, and the underlying strengthening mechanism is investigated in detail. [ABSTRACT FROM AUTHOR]

Objective: Investigating the changes in the oxidative stress levels and helper T lymphocyte (Th) subsets in patients with periodontitis and IgA nephropathy (IgAN) to determine their relationship. Background: IgAN has a high prevalence, poor prognosis, and no effective cure. Accumulating evidence has implicated a close relationship between periodontitis and chronic kidney diseases, in which both IgAN and chronic periodontitis show chronic inflammation and abnormal metabolism. However, few studies have been conducted on the relationship between the two diseases from this perspective. Methods: We divided 86 IgAN patients into patients with healthy periodontium (IgAN‐H, n = 34) and patients with periodontitis IgAN (IgAN‐P, n = 52); moreover, we divided 72 systemically healthy participants into patients with periodontitis (H‐P, n = 35) and participants with healthy periodontium (H‐H, n = 37). The proportions of Th subsets in peripheral blood were estimated using flow cytometry. Cytokine levels in plasma were assessed using cytokine assay kits. Enzyme‐linked immunosorbent assay was used to evaluate the plasma levels of oxidative stress. Results: Our results from analyzing the Th cell subsets indicated that Th2 cell counts in the IgAN‐P group were significantly lower than those in the IgAN‐H group, while Th17 cell counts were increased (p < 0.05). Moreover, the Th1/Th2 ratio and interleukin‐6 levels in the IgAN‐P group were significantly higher than those in the H‐H group (p < 0.01). Compared with that in the H‐H group, in the remaining three groups, plasma total oxidation state (TOS) levels were increased (p < 0.01), while plasma total antioxidant state (TAS) levels were decreased (p < 0.05). Furthermore, estimated glomerular filtration rate was negatively correlated with the probing depth and gingival bleeding index. IgAN was a risk factor for periodontitis, while TAS was a protective factor for periodontitis. The oxidative stress index (OSI) might be valuable for distinguishing periodontitis patients from healthy controls (area under the receiver operator characteristic curve = 0.951). Conclusion: IgAN is an independent risk factor of periodontitis, and the Th17 cell‐mediated inflammatory response might be associated with the occurrence of periodontitis in patients with IgAN. Patients with coexisting IgAN and periodontitis exhibit increased oxidative stress, in which TOS and OSI are potential biomarkers for diagnosing periodontitis. [ABSTRACT FROM AUTHOR]

High‐entropy alloys (HEAs) possess superior mechanical, thermal, and electronic properties, which attract great interest in the fields of photothermal, electrocatalysis, and magnetic applications. Herein, the nonlinear optical properties of FeCoNiAlTi HEA with a large specific surface area for the first time is investigated. Owing to the strong d–d interaction, the interband transition near the Fermi level could be enhanced in HEAs, leading to broadband optical absorption. Excitation with the picosecond laser source, the FeCoNiAlTi HEA possesses saturable absorption with a large modulation depth of 7.61% and 30.47% at 1 and 1.5 µm, respectively. Furthermore, at the higher excitation level at 1.5 µm, the saturable absorber exhibits a typical reverse saturable absorption property. Subsequently, the FeCoNiAlTi HEA on the tapered fiber first serves as the saturable absorber in the Yb‐doped fiber laser and the Er‐doped fiber laser, leading to the noise‐like pulses at 1 µm, and the stable Q‐switching, conventional soliton, and dissipative soliton resonance mode‐locking operations at 1.5 µm. This work confirms that the enhanced saturable absorption in HEAs can endow the high‐performance ultrashort pulse generation. [ABSTRACT FROM AUTHOR]

Continuous satellite measurements of the Earth's magnetic field have advanced the characterization of spatial‐temporal variations of the main field over the past two decades. To comprehend the underlying mechanism responsible for the geomagnetic field variations, we develop a novel core surface flow inversion scheme based on physics‐informed neural networks. The inversion method can account for the secular variation contributed by the interaction between the core flow and undetectable small‐scale magnetic fields. Based on the novel inversion framework, we derive a time‐dependent core surface flow model between 2000 and 2022 from the CHAOS‐7 core field model. The inverted core flow is then analyzed using the dynamic mode decomposition to extract wave‐like fluid motions. By calculating the magnetic secular acceleration contributed by each dynamic mode, we identify that the dynamic modes with period of about 10 and 7 years are responsible for geomagnetic jerks in the Atlantic and Pacific equatorial regions. Plain Language Summary: Over the past two decades, satellites have been continuously monitoring the Earth's magnetic field. The major part of the field comes from the liquid part of the Earth's core. Geomagnetic measurements show quick changes in the field, including sudden shifts known as geomagnetic jerks. These shifts are believed to be linked to specific fluid motions in the Earth's core. Our study aims to better understand these flows and their effects. We use a method involving neural networks to figure out the patterns of flow at the core surface from the satellite data. We then use a technique to separate these flow patterns into simpler wave‐like forms. This helps us see how each wave pattern affects changes in the magnetic field. Our findings suggest that wave‐like motions with period of about 10 and 7 years caused geomagnetic jerks in the Atlantic and Pacific regions near the equator. Key Points: A novel core surface flow inversion scheme based on physics‐informed neural networks is developedThe inverted flow from the CHAOS‐7 model is analyzed using the dynamic mode decomposition to extract wave‐like flow patternsGeomagnetic jerks in the Atlantic and Pacific equator are related to two dynamic modes with period about 10 and 7 years [ABSTRACT FROM AUTHOR]

This study investigated the radiation effects of commercially available medical disposable protective clothing materials under γ irradiation. FT‐IR, contact angle, DSC, OIT, and mechanical properties were used to examine the radiation effects of medical disposable protective clothing materials. The results showed when the radiation dose was less than or equal to 50 kGy, the FT‐IR spectra did not show any changes. However, when the radiation dose reached 70 kGy, new absorption peaks appeared in the infrared spectra of the TS−A and TS−B medical disposable protective clothing materials, indicating chemical changes. Contact angle analysis showed that medical disposable protective clothing materials were hydrophobic and had higher hydrophobicity on the inside than the outside under different packaging and irradiation conditions. Rheological analysis showed that the shear thinning phenomenon of medical disposable protective clothing materials increased significantly with the increase of radiation dose, and good rheological behavior was observed under vacuum packaging conditions when the radiation dose was 30 kGy. The crystallinity and initial crystallization temperature showed the order of vacuum, nitrogen, and air. The oxidation induction time trend was vacuum>nitrogen>air, while the fracture strength trend was nitrogen>vacuum>air. The mechanical properties met the national standard. [ABSTRACT FROM AUTHOR]