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Polyacrylonitrile pre-oxidized fiber（PANOF）is an emerging flame retardant material with low cost and high performance，showing a promising application potential as thermal protection materials in the aerospace field.Pretreated PANOF（t-PANOF）was obtained by the process of oil removing with acetone and surface modification using silane coupling agent KH570 in turn.Scanning electron microscopy（SEM），Fourier transform infrared spectroscopy（FT-IR）and X-ray photoelectron spectroscopy（XPS）were employed to figure out the changes of morphology and chemical structure of the fibers before and after pretreatment and their interfacial properties with silicone rubber（SR）.Effects of t-PANOF on the mechanical and thermal performances of SR were further investigated. With the presence of ceramic forming agent（CFA），the ablation responsive behaviors of CFA/t-PANOF/SR ternary composites were researched as well.The results show that the level of interfacial adhesion between fibers and rubber is significantly enhanced contributed from the pretreatment of PANOF，and the tensile strength of the composites is improved accordingly.However，with the increasing content of t-PANOF，the comprehensive mechanical properties of t-PANOF/SR composites show the trend that increase first and then decrease，indicating that the optimal dosage of the fibers is 5 to 10 phr.t-PANOF skeleton helps to not only enhance the dimensional stability of SR in high temperature and oxygen-rich environment，but also improve the ablation performance of CFA/t-PANOF/SR composites.The antioxidation ceramic layer with fiber skeleton as the main structure is formed on the surface of CFA/t-PANOF/SR composites under the high temperature aerobic gas with the heat flux density of 2 MW/m2，the corresponding linear and mass ablation rate are only 0.02 mm/s and 0.02 g/s respectively，which is expected to be utilized as an ablation material to satisfy the demands of the new generation of aerospace vehicles.

High-cholesterol diet (HCD) and fine particulate matter (PM2.5) are related to stroke. However, little is known about the combined effects of stroke, especially for females. This study investigated the brain injuries in Apolipoprotein E−/− (ApoE−/−) female mice exposed to HCD plus PM2.5 for 6 months. The protein levels of the genes related to stroke and the blood–brain barrier (BBB) in different groups of mice were measured. The molecular regulation mechanisms were explored. The results showed that HCD and PM2.5 co-exposure altered brain–body weight ratio, behavior, brain pathology, and inflammatory markers in mice relative to exposure to HCD or PM2.5 alone. Co-exposure significantly changed the expressions of HIF-1α and the key genes in its signaling pathway in the brains of mice compared to the single exposure. It suggests that the HIF-1α pathway exerts an important regulatory role in brain injury and behavioral abnormality in female mice after 6-month exposure to HCD plus PM2.5, which are potential mechanisms for HCD and PM2.5-triggering stroke in female individuals. [ABSTRACT FROM AUTHOR]

The atmosphere's fine particulate matter (PM2.5) can enter the liver through the circulatory system, leading to hepatic inflammation and fibrosis. As a non-flavonoid polyphenolic compound, resveratrol (RES) has anti-oxidant, anti-inflammatory and hepatoprotective effects, but the molecular mechanisms of liver fibrosis induced by PM2.5 exposure are still limited. In this study, we established an in vitro cell model to investigate the intervention effect of RES with different concentrations (5 and 20 μmol/mL) on mouse hepatic stellate cells (mHSCs) injury induced by PM2.5 (100 μg/mL). We determined the cell viability in mHSCs after treatment with PM2.5 or/and RES for 24 h. We investigated the intracellular oxidative stress by detecting the changes in reactive oxygen species (ROS), malondialdehyde (MDA), superoxide dismutase (SOD) and lactate dehydrogenase (LDH) levels. We also measured the protein expressions of fibrosis-related genes (α-SMA, Collagen I and Collagen III) and key genes (SIRT1, NF-κB, NLRP3, Cleaved-Caspase1, IL-1β) in the NLRP3 pathway in mHSCs exposed to PM2.5 with or without RES. The results showed that (1) PM2.5 has cytotoxic effects on mHSCs, whereas RES (5 μmol/L and 20 μmol/L) inhibited PM2.5-induced cytotoxicity and LDH leakage; (2) RES effectively reduces ROS and MDA production caused by PM2.5 while concurrently enhancing SOD levels, thereby improving cellular anti-oxidant capacity; (3) the expression of α-SMA, Collagen I and Collagen III were notably downregulated in the PM2.5 plus RES treatment group compared to the PM2.5-exposed group; (4) RES significantly increased SIRT1 expression and decreased the expression of NF-κB, NLRP3, Cleaved-Caspase1 and IL-1β in mHSCs exposure to PM2.5 compared to the PM2.5 group. These results demonstrate that RES can up-regulate SIRT1 and mitigate PM2.5-induced fibrosis by suppressing oxidative stress in mHSCs and the SIRT1/NF–κB/NLRP3 pathway activated by PM2.5. [ABSTRACT FROM AUTHOR]

This paper aims to investigate the impact of CQ on type 2 inflammatory response in MC903-induced AD mice. Methods: An AD mouse model was established via MC903 induction. After CQ treatment, AD mice were intraperitoneally injected with polyinosinic: polycyclic acid [poly (I:C)] or Nigericin. Dermatitis severity was scored, and the thickness of the left ear was measured. The pathological changes in mouse skin tissues were observed by H&E staining. The number of mast cells was counted via TB staining. The content of peripheral blood T-helper 2 (Th2) cells and levels of immunoglobulin E (IgE), thymic stromal-derived lymphopoietin (TSLP), interleukin (IL)-4, IL-13, interferon (IFN)-γ, IL-1β, and IL-18 were assessed by flow cytometry and ELISA. The levels of toll-like receptor 3 (TLR3), NLRP3, ASC, and cleaved caspase-1 proteins in skin tissues were determined by Western blot. Results: CQ treatment abated dermatitis severity and left ear thickness in AD mice, alleviated skin damage, reduced mast cell number, diminished IgE, TSLP, IL-4, and IL-13 levels, and peripheral blood Th2 cell content, with no significant changes in IFN-γ level. CQ alleviated type 2 inflammatory response in AD mice by inhibiting the activation of TLR3. CQ suppressed NLRP3 inflammasome activation. Activating TLR3/NLRP3 annulled CQ-mediated alleviation on type 2 inflammatory response in AD mice. Conclusion: CQ alleviated type 2 inflammatory response in AD mice by inhibiting TLR3 activation and NLRP3 inflammasome activation. [ABSTRACT FROM AUTHOR]

Phosphorus is an element essential to sustaining life, and its compounds are widely involved in the biogeochemical cycles on Earth. Although a handful of phosphorus-bearing species, e.g. PO, have thus far been detected in diatomic form in circumstellar envelopes, their formation processes are still poorly understood. In this study, we examine the structure and spectroscopy of the [Si, O, P] system. Based on high-level ab initio electronic structure calculations with the MRCI + Q and CCSD(T) methods, four isomers could be formed and the most stable form predicted to be bent at all theoretical levels. The doublet and quartet potential energy surfaces (PESs) of P(2D)/P(4S) + SiO(1Σ) reactions are explored, and the spectroscopic parameters of the key isomers involved in the reaction are calculated. The present study highlights the possibility of PO formation via photodissociation of bent-SiOP. The results are expected to aid in the spectroscopic detection of these triatomic phosphorous-bearing species and provide insights into similar reactions of isoelectronic systems. [ABSTRACT FROM AUTHOR]

During the physiological period, women have the problem of lateral and posterior leakage, and they expect to have period underwear that can reduce lateral and posterior leakage. This study is combined with menstrual needs, and in the crotch penetration layer, three types of yarns are used, seaweed viscose yarn, apocynum viscose yarn, and viscose yarn, as well as two fabric structures: honeycomb-shaped convex–concave stitching and grid-shaped convex point stitching. In the crotch absorption layer, three types of yarns are used, modal yarn, bamboo yarn, and viscose yarn, as well as two fabric structures: plush stitching and plain stitching. The above two parts establish a sample scheme according to full-factor experimental tests, and 12 knitted fabric samples were knitted. The experimental data were analyzed through SPSS one-way ANOVA. The results indicate that in terms of veil raw materials, the crotch penetration layer with seaweed viscose yarn has better penetration performance, while the crotch absorption layer with bamboo yarn has better absorption performance. In terms of fabric structure, the crotch penetration layer with grid-shaped convex point stitching has better penetration performance, while the crotch absorption layer with plush stitching has better absorption performance. This study provides a theoretical basis for the development of period underwear. [ABSTRACT FROM AUTHOR]

Fine particulate matter (PM2.5) is a common pollutant, and its health risk has attracted much attention. Studies have shown that PM2.5 exposure is associated with liver disease. The composition of PM2.5 is complex, and its hepatotoxic effects and lipid metabolism process are not well understood. In this study, we detected the concentrations of PM2.5 and its components (metals and polycyclic aromatic hydrocarbon (PAHs)) in the winter in Taiyuan, Shanxi Province, China, from 2017 to 2020 and then assessed the health risks. We also investigated the effects of different components (whole particles (WP), water-soluble particles (WSP), organic particles (OP)) of PM2.5 on the cytotoxicity and lipid metabolism in human liver cell line (HepG2) after 24 h of treatment. The changes in cytotoxicity indexes (LDH, IL-6, reactive oxygen species (ROS)) and lipids (triglyceride (TG), free fatty acid (FFA)) were measured after 24 h. The mRNA expression of lipid metabolism-related factors (SREBP1, CD36, MTTP) was determined by real-time quantitative RT-qPCR. Finally, the correlation between metals and PAHs with higher PM2.5 content in 4 years and biomarkers was analyzed. The results showed that: (1) The PM2.5 pollution was severe in Taiyuan during winter in 2017 and the subsequent four years. The calculation results of the metal enrichment factor (EF) value and PAHs characteristic ratio of PM2.5 showed that PM2.5 pollution sources differed in different years. (2) Exposure to metals and PAHs in PM2.5 did not cause a non-carcinogenic risk. Metals had no cancer risk, while PAHs inhaled in PM2.5 in 2017 and 2018 had a potential cancer risk. The atmospheric PM2.5 pollution in Taiyuan has had a downward trend, but the PAHs in the PM2.5 of 2017–18, when the pollution is relatively serious, have a potential carcinogenic risk. (3) WP, OP and WSP inhibited cell survival rate from 2017 to 2020, and OP had higher cytotoxicity at the same concentration. (4) WP, OP and WSP increased the levels of LDH, IL-6, TNF-α, ROS, MDA, TG and FFA, and inhibited SOD activity in a dose-effect relationship. The organic components in PM2.5 are more toxic to HepG2 cells and affect the expression of lipid metabolism-related factors at the transcriptional level. (5) The mRNA expressions of factors related to lipid synthesis, uptake, oxidation and output were up-regulated after treatment with PM2.5 and its components, suggesting a lipid metabolism disorder. (6) The biomarkers were associated with certain metals (Zn, Pb, Cu and Cr) and PAHs in PM2.5. These suggested that PM2.5- and PM2.5-bound organic matter caused HepG2 cytotoxicity and affected lipid metabolism. [ABSTRACT FROM AUTHOR]