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Highlights Inorganic fillers like hexagonal boron nitride (h‐BN) have the potential to enhance the thermal conductivity of polymer mixtures. However, it has been restricted due to poor dispersion of particles in polymer matrices by melt mixing process. The addition of inorganic powders into sticky prepolymer is expected to alleviate the aggregation of powders. In this paper, h‐BN/polymethyl methacrylate (PMMA) composites were prepared by in situ polymerization of methyl methacrylate (MMA) with 5 and 20 μm of h‐BN particle as fillers respectively, for even distribution of fillers with in composites. The structures and properties of composites were characterized by FT‐IR, DSC, TGA, SEM, laser thermal conductivity meter and universal electronic tester. By SEM, it can be seen that a highly uniform dispersion of h‐BN in PMMA. When the mass fraction of h‐BN is 20 wt%, the thermal conductivity of the composites is increased by 107% for 5 μm h‐BN and 189% for 20 μm h‐BN, respectively. With the mass constituting of 5 wt% h‐BN, majority of mechanical characteristics of the composite, such as tensile strength, tensile modulus, along with impact strength, are enhanced, alongside a decrease in bending strength. This work would provide a filling strategy of h‐BN into the polymer matrices to achieve uniform dispersion, and enhance both the thermoconductivity and mechanical strength of thermoplastic composites. A technique for creating h‐BN/PMMA composites using in suit redox polymerization. Ehancing the thermal conductivity of these composites is achievable through the even distribution of h‐BN flakes within the PMMA matrix. It provides a reference for the design of future h‐BN/PMMA composites with favorable the thermal conductivity which achieves a good balance between performance and cost. [ABSTRACT FROM AUTHOR]

Ischemic stroke (IS) is a disease with a high mortality and disability rate worldwide, and its incidence is increasing per year. Angiogenesis after IS improves blood supply to ischemic areas, accelerating neurological recovery. β-asarone has been reported to exhibit a significant protective effect against hypoxia injury. The ability of β-asarone to improve IS injury by inducing angiogenesis has not been distinctly clarified. The experimental rats were induced with middle cerebral artery occlusion (MCAO), and oxygen-glucose deprivation (OGD) model cells were constructed using human microvascular endothelial cell line (HMEC-1) cells. Cerebral infarction and pathological damage were first determined via triphenyl tetrazolium chloride (TTC) and hematoxylin and eosin (H&E) staining. Then, cell viability, apoptosis, and angiogenesis were assessed by utilizing cell counting kit-8 (CCK-8), flow cytometry, spheroid-based angiogenesis, and tube formation assays in OGD HMEC-1 cells. Besides, angiogenesis and other related proteins were identified with western blot. The study confirms that β-asarone, like nimodipine, can ameliorate cerebral infarction and pathological damage. β-asarone can also upregulate vascular endothelial growth factor A (VEGFA) and endothelial nitric oxide synthase (eNOS) and induce phosphorylation of p38. Besides, the study proves that β-asarone can protect against IS injury by increasing the expression of VEGFA. In vitro experiments affirmed that β-asarone can induce viability and suppress apoptosis in OGD-mediated HMEC-1 cells and promote angiogenesis of OGD HMEC-1 cells by upregulating VEGFA. This establishes the potential for β-asarone to be a latent drug for IS therapy. [ABSTRACT FROM AUTHOR]

Based on 4 annual waves of data from a large sample of Chinese college students (N = 2,329, M[subscript age] = 18.40 years old, SD = 0.85; 63.10% females), this study examines the within-person and between-person effects in the association between problematic Internet use (PIU) and mental health issues. Results of analyses using the developmental equilibrium model (i.e., an autoregressive, cross-lagged panel model) demonstrate a "reciprocal" positive association between PIU and mental health issues consistently across waves. In contrast, results of analyses utilizing the random intercept, cross-lagged panel model (i.e., a model that can disaggregate within-person and between-person effects) indicate a "unidirectional" positive within-person effect from PIU to mental health issues (rather than the reverse) consistently over time, while controlling for the between-person effects that exist when comparing different individuals. Such findings highlight the importance of disaggregating within-person and between-person effects in understanding the nature of the temporal dynamics of the association between PIU and mental health.

Flood is a natural disaster that threatens the safety of people's lives and property, and there are myths and legends related to flood disasters in China and abroad. The Noah's Ark is one of the most famous stories in the Bible in the West, and the story of Yu the Great Harnesses the Flood is a well-known story in China. By comparing the story of Noah's Ark and Yu the Great Harnesses the Flood, this paper explores the deep cultural differences between China and the West, so as to understand and tolerate each other in intercultural communication and reduce unnecessary cultural conflicts.

A measurement method based on the homography matrix and partial area effect is studied to improve the precision of the visual measurement of the bearing size. Firstly, the camera is calibrated to obtain its distortion coefficient, and the image is corrected for distortion. Secondly, the relationship between the pixel plane and the bearing imaging plane is determined by solving the homography matrix with a chessboard. Finally, the sub-pixel edge contour of the bearing is obtained through the improved partial area effect, and the pixel coordinates are mapped to the world coordinates according to the homography matrix. The feature size is obtained by fitting the mapping points. Experimental results showed that the transformation of the homography matrix is more accurate than the pixel equivalent in the process of converting the pixel size to the actual size. The improved partial area effect sub-pixel edge detection results are better than the partial area effect and Zernike moment. The measurement error for the bearing outer diameter is less than 0.05 mm and is within 0.5 pixel. [ABSTRACT FROM AUTHOR]