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SiCf/SiC composites were prepared by melt infiltration（MI）process，chemical vapor infiltration combined with precursor infiltration and pyrolysis（CVI+PIP）process and precursor infiltration and pyrolysis（PIP）process，respectively. The microstructures，compositions and properties of SiCf/SiC composites prepared by different processes before and after water-oxygen corrosion at 1300 ℃ were characterized by scanning electron microscopy and its accompanying EDS and X-ray diffractometer. The results show that the distributions of oxygen elements of the fracture surface is obviously different in the composites prepared by different processes，and the phases after corrosion are closely related to the preparation processes. The strength retention rate and modulus retention rate of SiCf/SiC composites prepared by MI process are 84% and 76% after water oxygen corrosion at 1300 ℃ for 50 hours. The strength retention rate of SiCf/SiC composites prepared by CVI+PIP is 64%，and the modulus is increased by 6%. The SiCf/SiC composites prepared by PIP process has a strength retention rate of 49% and a modulus increase of 17%. The composite materials prepared by MI process show oxidation mass gain，while the composite materials prepared by CVI+PIP and PIP process show oxidation mass loss，which are mainly related to its microstructures and compositions.

The effect of thermal exposure at 1000 ℃ to 1200 ℃ on the properties of porous matrix Al2O3/Al2O3 ceramic matrix composites was studied. The results show that the thermal exposure at 1000 ℃ for 100 h has no effect on the tensile strength of the composites. After 100 h at 1100 ℃, the tensile strength of the composites decreases slightly, and after 100 h at 1200 ℃, the tensile strength of the composites decreases obviously. The effects of different thermal exposure durations at 1200 ℃ on the properties of Al2O3/Al2O3 composites, alumina fibers and alumina matrix are further studied, and the micro morphologies of the samples are characterized by optical microscopy and SEM. The results show that the thermal exposure at 1200 ℃ for 100 h has little effect on the performance of alumina fiber, but has a great effect on the alumina matrix. After the thermal exposure at 1200 ℃ for only 10 h, the porosity of alumina matrix is significantly reduced and the density is significantly increased. It can be seen from the SEM morphology of the matrix fracture that with the increase of thermal exposure time at 1200 ℃, the alumina grain size of the matrix gradually increases and the matrix is further sintered. Correspondingly， it can be seen from the fracture morphology of the Al2O3/Al2O3 composite that the length and number of fibers pulled out also decrease significantly. The degradation of the properties of the composites after high temperature thermal exposure is mainly due to the further sintering of alumina matrix, and the densification of porous matrix reduces the toughening effect of the composites.

SiC/SiC composites have the characteristics of high hardness and brittleness, and they are typical difficult materials to process. Laser processing is mainly used to prepare cooling holes. Millisecond and nanosecond lasers mainly use photothermal action to rapidly heat the target material, melt and gasify it, and remove the material with the help of high-speed gas flow. Due to the short pulse duration and high peak power of nanosecond laser, it is easier to realize the gasification of materials, and the thermal effect caused is less. In this paper, millisecond and nanosecond lasers are used to make holes in SiC/SiC composites respectively. The results show that for cooling holes with a diameter of 0.6 mm and an inclination angle of 25 °, the processing time of nanosecond laser is 8.7 times longer than that of millisecond laser. The two kinds of laser processed holes have certain taper, in which the hole cone angle of nanosecond laser processing is 2.12 ° and that of millisecond laser processing is 1.49 °. There are residues in the inner, outlet end and inlet end of the hole processed by millisecond laser, and there are obvious remelting oxidation zone and heat affected zone around the hole. However, there is no obvious residue inside the hole processed by nanosecond laser, there is discoloration at the inlet end of the laser, there is no discoloration at the outlet end, and there is no obvious remelting oxidation zone and heat affected zone. The results of elemental analysis show that both kinds of laser processing can cause the oxidation of materials.

BN and BN/SiC coatings were deposited on the surface of two typical domestic SiC fibers by CVI process, and the composition of coatings was analyzed. The tensile strength of monofilaments was evaluated by Weibull distribution, and the tensile fracture failure behaviors of the fiber before and after depositing coatings were studied. The results show that the carbon-rich layer with appropriate thickness (15 nm) can heal the defects on the surface of SiC fiber and reduce the possibility of fiber failure from the surface. The thickness of the coating prepared by the CVI process is uniform and the composition is stable. After depositing BN and BN/SiC coatings, the tensile strength and elastic modulus of the two kinds of SiC fibers are decreased. BN coatings can also repair the surface defects of the fiber, so that the fiber strength distribution tends to be concentrated. Different from the uncoated fibers, the tensile fracture failure sources of coated fibers are the surface defects of BN and SiC coatings, respectively.

This study aims to explore the role and mechanism of circ-IARS in non-small-cell lung cancer (NSCLC) progression. Expression of circ-IARS, microRNA (miR)-1252-5p, and hepatoma-derived growth factor (HDGF) was measured by real-time quantitative PCR and western blotting. The interactions among circ-IARS, miR-1252-5p, and HDGF were determined by dual-luciferase reporter assay and RNA immunoprecipitation. Cell behaviors were measured by 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide (MTT), 5-ethynyl-2′-deoxyuridine (EdU) assay, flow cytometry, scratch wound assay, and transwell assay, and validated in in vivo xenograft model. Exosomes were isolated using commercial kit, and the expression and functions of exosomal circ-IARS (exo-circ-IARS) were analyzed as described above. Results showed that the expression of circ-IARS was upregulated in NSCLC cells, NSCLC tissues, and serum exosomes from NSCLC patients. circ-IARS exhaustion antagonized cell proliferation, cell cycle progression, migration, and invasion and promoted apoptosis in NSCLC. Molecularly, circ-IARS could sponge miR-1252-5p to modulate the expression of the downstream gene HDGF. In addition, miR-1252-5p downregulation attenuated circ-IARS exhaustion-mediated effects in H1299 and A549 cells. MiR-1252-5p mimic-induced effects were relieved by increasing HDGF expression in H1299 and A549 cells. Exo-circ-IARS promoted H460 cell proliferation, migration, and invasion and inhibited cell apoptosis. Silencing circ-IARS retarded tumor growth of NSCLC cells in vivo. Thus, circ-IARS, secreted by exosomes, was a novel oncogene in NSCLC and regulated the malignant development of NSCLC cells via circ-IARS/miR-1252-5p/HDGF competing endogenous RNA regulatory axis.

The biology of natural killer (NK) cells in commonly used mouse models is discussed in this review, along with their crucial function in a variety of immunological responses. It has been demonstrated that the formation, maturation, subtype variety, and immunological recognition mechanisms of NK cells from various mice strains exhibit notable differences. These variations shed light on the intricacy of NK cell function and offer crucial information regarding their possible uses in treating human illnesses. The application of flow cytometry in mouse NK cell research is also covered in the article. Improved knowledge of the biology of NK cells across species may facilitate the development of new NK cell-based therapeutic approaches. [ABSTRACT FROM AUTHOR]

High‐voltage cathodes improve the energy density of the batteries, which satisfies the pursuit of high‐energy‐density lithium metal batteries (LMBs). However, layered lithium cobalt oxide (LiCoO2) cathodes suffer from severe interfacial side reactions under high voltage (4.6 V), which is detrimental for practical applications. Herein, a functional lithium salt, 2,2,6,6‐tetramethyl‐1‐piperidinyloxyl‐4‐sulfate lithium (TEMPO‐OSO3Li) is developed that possesses radical‐scavenging anion TEMPO‐OSO3−. The anion accumulates at the cathode interface and effectively scavenges free radicals under the electric field at high voltage, thereby, inhibiting the electrolyte decomposition and interfacial side reactions. As a result, the Li||LiCoO2 batteries with dual‐salt (TEMPO‐OSO3Li (0.02 m) and LiPF6 (1 m)) electrolyte exhibit high capacity retention of 92% after 100 cycles at 4.6 V and maintain 81% after 200 cycles, which is superior to that of the baseline electrolyte (26%). The work demonstrates a promising strategy for designing electrolyte salts to realize the practical application of LiCoO2 at high voltage. [ABSTRACT FROM AUTHOR]

Background: Inflammatory bowel disease (IBD) is affected by interactions between intestinal microbial factors, abnormal inflammation, and an impaired intestinal mucosal barrier. Neutrophils (NE) are key players in IBD. Fusobacterium nucleatum (F. nucleatum) is reported to contribute to IBD progression. However, the relationship between F. nucleatum, abnormal inflammation, and intestinal barrier impairment should be interpreted to understand the role of F. nucleatum in IBD. Methods: Dextran sulfate sodium (DSS)-induced colitis model was established and mice were orally administered with F. nucleatum. F. nucleatum colonization was confirmed by fluorescence in situ hybridization (FISH) and PCR. Intestinal barrier impairment was investigated by tight junction protein expression. Immuno-histochemistry (IHC) for Ly6G and flow cytometry detection to measure NE chemotaxis in mouse colon tissues. Caco-2 monolayers were used to evaluate epithelial integrity and permeability in vitro. A transwell model involving caco-2 cells and NE co-culture was used to assess NE chemotaxis. NE chemokines were measured by ELISA. A mouse model of NE exhaustion using an anti-Ly6G antibody was used to identify the role of NEs in F. nucleatum-induced colitis. Transcriptome sequencing and bioinformatics analysis were applied to screen cytokines and signaling pathways. Results: Administration of F. nucleatum aggravated colitis in the DSS model. F. nucleatum infection downregulates ZO-1 and Occludin expression and increases intestinal permeability. Additionally, F. nucleatum-induced NE chemotaxis decreases the integrity and permeability of the caco-2 monolayer. F. nucleatum-induced NE chemotaxis is dependent on IEC-derived interleukin 8 (IL-8) secretion, mediated by the TLR2/ERK signaling pathway. In addition, NE exhaustion in mice inhibited F. nucleatum-induced intestinal barrier impairment and colitis. Conclusion: F. nucleatum improves NE chemotaxis by infecting intestinal epithelial cells (IECs) to secrete IL-8 and aggravate intestinal barrier impairment, contributing to the progression of intestinal inflammation. Examining and eliminating F. nucleatum could be a valuable microbiome-based method for IBD surveillance and prevention. [ABSTRACT FROM AUTHOR]

Objectives Methods Results Conclusions This study aimed to analyze the role of circSEC24A in non‐small cell lung cancer (NSCLC) and its underlying mechanism.RNA levels of circSEC24A, microRNA‐1253 (miR‐1253), and KLF transcription factor 8 (KLF8) were detected by quantitative real‐time polymerase chain reaction. Protein expression was analyzed by western blot or immunohistochemistry assay. Cell proliferation and apoptosis were investigated by colony formation assay, 5‐ethynyl‐2′‐deoxyuridine assay, and flow cytometry analysis. Glycolysis was evaluated by commercial kits. Dual‐luciferase reporter assay and RNA immunoprecipitation assay were conducted to identify the associations among circSEC24A, miR‐1253, and KLF8. Xenograft mouse model assay was used to evaluate the effect of circSEC24A on tumor tumorigenesis.CircSEC24A and KLF8 were upregulated, while miR‐1253 was downregulated in NSCLC. CircSEC24A knockdown inhibited proliferation and glycolysis but induced the apoptosis of NSCLC cells. CircSEC24A acted as a miR‐1253 sponge and regulated NSCLC cell malignancy by targeting miR‐1253. KLF8 was identified as a target of miR‐1253, and its overexpression attenuated miR‐1253‐induced effects in NSCLC cells. Besides, circSEC24A upregulated KLF8 by sponging miR‐1253. Further, circSEC24A knockdown suppressed NSCLC cell tumorigenesis in vivo.CircSEC24A silencing inhibited NSCLC cell malignancy through the miR‐1253/KLF8 pathway, providing a potential therapeutic target for NSCLC. [ABSTRACT FROM AUTHOR]

Arid areas cover approximately 41% of Earth's land surface and support more than 38% of the global population. As an important part of drylands, oases are the main carriers of human production, socioeconomic activity, and the ecological environment. Oases typically sustain nearly all of an arid region's human population and produce nearly 95% of its gross domestic product. The ongoing intensification of global warming and human activities has resulted in water stress and water-related environmental problems in arid areas, along with land degradation and desertification. The risk of water shortage and natural disasters in these regions has also increased. The solution to mitigate these environmental issues and achieve ecological security and sustainable socioeconomic development is to accelerate the modernization of oasis ecological agriculture. This can be accomplished by coordinating the contradictions between agricultural, industrial, and domestic water use and ecological water use in arid areas, thereby improving the level of management in oases and strengthening their ability to cope with climate change. [ABSTRACT FROM AUTHOR]