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In order to investigate the stress corrosion cracking behavior of ultra-high strength stainless steel， the influence of Nb microalloying on the corrosion fatigue properties of Cr-Co-Ni-Mo series ultra-high strength stainless steel was studied by OM， XRD， TEM and other testing methods in combination with corrosion fatigue test. The results show that the steel has stress corrosion sensitivity in 3.5% NaCl solution， and the stress corrosion cracking mechanism of the steel was a mixed mechanism involving hydrogen embrittlement and anodic dissolution. Niobium alloying improved the corrosion fatigue performance of the steel， that is， the corrosion fatigue strength of steel increases from 440 MPa to 495 MPa after adding 0.11% Nb. The main reason is that niobium alloying refined the grain size of steel， promoted the precipitation of irreversible hydrogen trap of NbC in steel， and increased the amount of prior austenite grain boundaries， the proportion of low-angle grain boundaries， the number of Σ3 grain boundaries， and the volume fraction of austenite in steel.

This study was conducted to isolate and identify Bifidobacterium from the feces of Kazakh school-age children in Yining, Xinjiang and evaluate the in vitro probiotic characteristics of B. longum subsp. longum isolates. By groEL gene sequencing and repetitive element sequence-based polymerase chain reaction (rep-PCR) fingerprinting, 416 Bifidobacterium strains were identified to belong to B. longum, B. bifidum, B. pseudocatenulatum, B. catenulatum and B. breve. According to the fingerprints of B. longum subsp. longum, 27 genotypes showed genetic differences between individual strains and the coexistence of multiple strains in the gut was found. The in vitro experimental results showed that out of 27 representative strains, strains 2B3-21, 1B23-11, 2B33-3, and 1B68-16 were optimal in acid and bile salt tolerance, strains 1B68-16, 2B13-5, 2B33-3, and 1B39-2 had broad-spectrum antibacterial properties, and strains 1B38-1, 2B33-3, 1B68-16, and 2B13-28 showed a strong antioxidant capacity. Considering the antibiotic resistance of all strains and their ability to utilize plant-derived glycans, strains 1B38-1 and 2B13-28 were selected to assess their in vivo probiotic potentials. This study may lay the foundation for the development of excellent probiotics and related products for populations from specific areas.

Objective:To investigate the imaging characteristics of thymoma and mediastinal lymphoma using spectral CT and evaluate whether the quantitative information can improve the differential diagnosis of these diseases.Methods:This retrospective study was approved by the institutional review board, and written informed consent was obtained from all patients. Overall, 39 patients with mediastinal tumors (24 thymomas and 15 mediastinal lymphomas) were examined with CT spectral imaging during the arterial phase (AP) and venous phase (VP). Iodine concentrations were derived from iodine-based material-decomposition CT images and normalized to the iodine concentration in the aorta. The difference in normalized iodine concentrations (NICs), HU curve slop(λHU), and the differences between AP and VP for CT values of lesions in 70 Kev were calculated. The two-sample t-test was performed to compare quantitative parameters, and non-quantitative parameters were compared with the Chi-square test (Fisher exact). Receiver operating characteristic (ROC) curves were generated to help establish threshold values for the parameters required for the significant differentiation of thymomas from mediastinal lymphomas. Two readers qualitatively assessed the lesion types according to the imaging features. The sensitivity and specificity of the qualitative and quantitative studies were compared.Results:NICs during the VP and λHU during the AP in patients with mediastinal lymphomas differed significantly from those in patients with thymomas. The mean NICs during the VP were 0.28 ± 0.08  mg ml-1 (±standard deviation) vs 0.49 ± 0.15  mg ml-1, respectively. The λHU during the AP was 0.69 ± 0.17 vs 1.26 ± 0.74, respectively. The NICs during the VP and λHU during the AP had high sensitivity and specificity in differentiating mediastinal lymphomas from thymomas. The tumor location, margin, necrosis, presence of swollen mediastinal lymph nodes, relationship with adjacent vessels, and enhancement pattern differed significantly between the groups (p < 0.05). The combination of NICs and λHU had higher sensitivity and specificity than did those of conventional qualitative CT image analysis during the combined phases.Conclusion:CT spectral imaging has promising potential for the diagnostic differentiation of mediastinal lymphomas and thymomas. The iodine content and λHU could be valuable parameters for differentiating thymomas and mediastinal lymphomas.Advances in knowledge:The iodine content and λHU, provided by spectral CT, could be used as new parameters to distinguish mediastinal lymphomas from thymomas.

Background: The Interleukin-6 (IL-6)-signal transducer and activator of transcription 3 (STAT3) pathway, along with the cyclic GMP-AMP synthase (cGAS)-stimulator of interferon genes (STING) pathway, are critical contributors to neuroinflammation in Alzheimer's disease (AD). Although previous research outside the context of AD has indicated that the IL-6-STAT3 pathway may regulate the cGAS-STING pathway, the exact molecular mechanisms through which IL-6-STAT3 influences cGAS-STING in AD are still not well understood. Methods: The activation of the IL-6-STAT3 and cGAS-STING pathways in the hippocampus of 5×FAD and WT mice was analyzed using WB and qRT-PCR. To explore the effects of IL-6 deficiency, Il6+/− mice were crossed with 5×FAD mice, and the subsequent impact on hippocampal STAT3 pathway activity, cGAS-STING pathway activation, amyloid pathology, neuroinflammation, and cognitive function was evaluated through WB, qRT-PCR, immunohistochemistry, ThS staining, ELISA, and behavioral tests. The regulatory role of STAT3 in the transcription of the Cgas and Sting genes was further validated using ChIP-seq and ChIP-qPCR on hippocampal tissue from 5×FAD and Il6−/−: 5×FAD mice. Additionally, in the BV2 microglial cell line, the impact of STAT3 activation on the transcriptional regulation of Cgas and Sting genes, as well as the production of inflammatory mediators, was examined through WB and qRT-PCR. Results: We observed marked activation of the IL-6-STAT3 and cGAS-STING pathways in the hippocampus of AD mice, which was attenuated in the absence of IL-6. IL-6 deficiency reduced beta-amyloid deposition and neuroinflammation in the hippocampus of AD mice, contributing to cognitive improvements. Further analysis revealed that STAT3 directly regulates the transcription of both the Cgas and Sting genes. These findings suggest a potential mechanism involving the STAT3-cGAS-STING pathway, wherein IL-6 deficiency mitigates neuroinflammation in AD mice by modulating this pathway. Conclusion: These findings indicate that the STAT3-cGAS-STING pathway is critical in mediating neuroinflammation associated with AD and may represent a potential therapeutic target for modulating this inflammatory process in AD. [ABSTRACT FROM AUTHOR]

Fuchs endothelial corneal dystrophy (FECD) is a leading cause of corneal endothelial degeneration resulting in impaired visual acuity. Excessive deposition of extracellular matrix (guttae) on Descemet's membrane (DM) is the hallmark of FECD. We sought to detect the guttae area rapidly using aniline blue (AB) staining in FECD mouse model. FECD mouse model was established via ultraviolet A (UVA) exposure. Masson's trichrome staining was utilized to stain the corneal sections. AB staining was utilized to stain both whole cornea tissues and stripped Descemet's membrane‐endothelium complex (DMEC) flat mounts, while immunofluorescence staining of collagen I was employed to stain guttae areas. In Masson's trichrome staining, corneal collagen fibrils were stained blue with AB. The DMEC flat mounts were stained into relative dark blue areas and relative light blue areas using 2% AB staining. The areas of dark blue could almost overlap with collagen I‐positive areas, and have an acellular centre and a moderately distinct boundary line with the surrounding corneal endothelial cells. In conclusion, AB staining is a rapid and effective method for the evaluation of the guttae areas in the FECD mouse model. [ABSTRACT FROM AUTHOR]

A facile and eco‐friendly dimethyl sulfoxide‐mediated solution aging (DMSA) treatment is presented to control the crystallization dynamics of methylammonium (MA)‐free wide‐bandgap (WBG) perovskite films, enhancing film quality, and morphology for high‐performance tandem solar cells. The comprehensive structural, morphological, and characterization analyses reveal that the DMSA treatment significantly enhances composition and morphology homogeneity while suppressing halide segregation. Consequently, opaque, and semi‐transparent MA‐free WBG perovskite solar cells (PSCs) exhibit remarkable power conversion efficiencies (PCEs) of 18.28% and 17.61%, respectively. Notably, the unencapsulated DMSA‐treated devices maintain 95% of the initial PCE after 900 h of continuous operation at 55 °C ± 5 °C. Furthermore, stacking semi‐transparent DMSA‐treated PSCs as top cells in a 4T tandem configuration, along with silicon heterojunction (SHJ), lead–tin (Pb–Sn) alloyed PSCs, and organic photovoltaics (OPV) as bottom cells, yields impressive PCEs of 28.09%, 26.09%, and 25.28%, respectively, for the fabricated tandem cells. This innovative approach opens new avenues for enhancing the photo‐stability and photovoltaic performance of perovskite‐based tandem solar cells. [ABSTRACT FROM AUTHOR]

The removal of nitrogen trifluoride (NF3) is of significant importance in atmospheric chemistry, as NF3 is an important anthropogenic greenhouse gas. However, the radical species OH and O(1D) in atmospheric conditions are nonreactive towards NF3. It is necessary to explore possible ways to remove NF3 in atmosphere. Therefore, the participation of water molecules in the reaction of NF3 with OH was discussed, as water is abundant in the atmosphere and can form very stable complexes due to its ability to act as both a hydrogen bond donor and acceptor. Systemic DFT calculations carried out at the CBS-QB3 and ωB97XD/aug-cc-pVTZ level of theory suggest that water molecules could affect the NF3 + OH reaction as well. The energy barrier of the SN2 mechanism was decreased by 8.52 kcal/mol and 10.58 kcal/mol with the assistance of H2O and (H2O)2, respectively. Moreover, the presence of (H2O)2 not only reduced the energy barrier of the reaction, but also changed the product channels, i.e., formation of NF2O + (H2O)2-HF instead of NF2OH + (H2O)2-F. Therefore, the removal of NF3 by reaction with OH is possible in the presence of water molecules. The results presented in this study should provide useful information on the atmospheric chemistry of NF3. [ABSTRACT FROM AUTHOR]

Objective To investigate the effect of mechanical thrombectomy using Solitaire stent combined with dual antiplatelet therapy (DAPT) on limb function and vascular reocclusion in patients with acute cerebral infarction. Methods A total of 134 patients with acute cerebral infarction who received treatment in our hospital from February 2020 to August 2023 were selected as samples. According to whether the patients regularly took aspirin and clopidogrel every day one week before surgery, they were divided into observation group (taking the medications) and control group (without taking medications), with 67 cases in each. The control group was given mechanical thrombectomy, and the observation group was treated with DAPT combined with mechanical thrombectomy. Outcomes measured included revascularization one week after treatment, and neurological and limb function assessment using NIHSS and FMA scale at baseline, 1 day, 1 week, and 1 month after treatment. Brain hemodynamics (CVR, Qmean, and Vmean) and thrombosis markers (TXB2, CD62P, and 6-keto-PGF1α) were evaluated pre-treatment and one month after treatment. Vascular reocclusion three months after treatment and its correlation with hemodynamics and thrombosis factors were analyzed. Results After treatment, higher revascularization rate, FMA score, Qmean, Vmean, and 6-keto-PGF1α level, and lower NIHSS score, CVR, TXB2, and CD62P level were found in the observation group (P < 0.05) . The incidence of vascular reocclusion was also lower in the observation group. Logistic analysis indicated that brain hemodynamic indicators and the level of thrombosis-related factors influenced vascular reocclusion occurrence (P < 0.05) . Conclusion Mechanical thrombectomy using Solitaire stent combined with DAPT helps the recovery of limb function in patients with acute cerebral infarction and reduces the risk of vascular reocclusion. [ABSTRACT FROM AUTHOR]

Background: While there is a scarcity of studies utilizing strain elastography (SE) for the endometrium, commonly used gynecologic ultrasound instruments are equipped with built-in elastography modalities, primarily SE. With the objective of facilitating comprehensive examinations for gynecologic patients on a single ultrasound instrument, we undertook this study. Therefore, our aim was to study the value of SE ultrasonography in the assessment of endometrial elasticity in normal women. Methods: Three hundred and twenty normal women were recruited at our hospitals from November 2021 to December 2022. Each volunteer underwent a transvaginal two-dimensional (2D) and SE ultrasound during either the endometrial proliferative or secretory phase. The 2D ultrasound indices obtained included endometrial thickness, echo type (type A, B, and C), and blood flow grading (grades 0, 1, 2, and 3). SE indices obtained included endometrial strain values, myometrial strain values, and endometrial strain ratios. Differences in endometrial ultrasound indices between different menstrual cycles and different age groups were compared. Results: Comparison of 2D ultrasound parameters revealed that endometrial thickness in the proliferative phase endometrium group was smaller than that in the secretory phase endometrium group, with a statistically significant difference. Additionally, there was a statistically significant difference in endometrial echo types between the two groups, while the disparity in endometrial blood flow grading was not significant. Regarding SE parameters, the median and mean values of endometrial strain ratio in the proliferative phase endometrium group were smaller than those in the secretory phase endometrium group, showing a statistically significant difference. However, there were no significant differences observed between the two groups in endometrial strain and myometrial strain in the fundus. Furthermore, there were no significant differences in any of the endometrial ultrasound indices among the different age groups. Conclusions: SE can reflect changes in endometrial stiffness in different menstrual cycles and is an important tool for assessing endometrial softness. [ABSTRACT FROM AUTHOR]