Topological Magneto-optical Effect from Skyrmions in Two-Dimensional Ferromagnets.

Skyrmions in two-dimensional (2D) magnetic materials are considered as ideal candidates for information carriers in next-generation spintronic devices. However, conventional methods for elucidating the physical properties of skyrmions have limited the development of skyrmions in diverse 2D magnetic material systems due to their requirements for electrical conductivity. To overcome this limitation, we propose to utilize an optical method (magneto-optical Kerr technique) to detect the skyrmions in 2D magnetic materials. Herein, the graphene/Fe3GeTe2/graphene vertical van der Waals (vdW) heterostructure devices are fabricated to generate stabilized skyrmions by applying out-of-plane current. In combination with magnetic circular dichroism measurements, we observe topological-reflective magnetic circular dichroism (T-RMCD) effects in Fe3GeTe2 flakes and attribute the peak-shaped component in T-RMCD to the annihilation of skyrmion magnetic domains. Notably, the T-RMCD signal can maintain up to a temperature as high as the Curie temperature of Fe3GeTe2 flakes (∼200 K). Our work provides a universal, contactless, and nondestructive approach for studying the physical properties of skyrmions in 2D vdW magnetic materials while adding another degree of freedom to the modulation of skyrmions.

Circulating tumor cells shed large extracellular vesicles in capillary-sized bifurcations.

Circulating tumor cells (CTCs) and their clusters are the drivers of metastasis, but their interactions with capillary beds are poorly understood. Using microfluidic models mimicking human capillary bifurcations, we observed cell size- and bifurcation-dependent shedding of nuclei-free fragments by patient CTCs, CTC-derived explant cells and numerous cancer cell lines. Shedding reduced cell sizes up to 61%, facilitating their transit through bifurcations. We demonstrated that shed fragments were a novel class of large extracellular vesicles (LEVs), whose proteome was associated with immune-related and signaling pathways. LEVs were internalized by endothelial and immune cells, disrupted endothelial barrier integrity and polarized monocytes into M2 tumor-promoting macrophages. Cumulatively, these findings suggest that CTCs shed LEVs in capillary beds that drive key processes involved in the formation of pre-metastatic niches.

Association between Soccer Participation and Liking or Being Proficient in It: A Survey Study of 38,258 Children and Adolescents in China.

Soccer participation among children and adolescents is low in China. To achieve a coordinated development of soccer in all regions and to promote the physical health of children and adolescents, this study aims to identify the influencing factors regarding the participation of children and adolescents in soccer programs through a cross-sectional analysis of the "soccer population" of children and adolescents. A total of 38,258 children and adolescents aged 7-18 years were included in this study. In addition, the analysis was conducted by dividing the regions where the children and adolescents live into three parts according to socioeconomic status, and by incorporating five dimensions, including environment, family, school, community, and individual levels to find the influencing factors of children and adolescents' participation in soccer. Chi-square test, Pearson's correlation, and one-way logistic regression analyses were used. The results showed that the area (r = 0.487) and the average annual precipitation (r = -0.367) were associated with the participation of children and adolescents in soccer programs. Moreover, the percentage of children and adolescents who participated in soccer programs (24.5%) was higher than those who liked soccer or were proficient in it (14.4%). Meanwhile, parental encouragement and support (OR = 0.627; 95% CI, 1.102-3.179), as well as the accessibility (OR = 0.558; 95% CI, 1.418-2.155), availability (OR = 1.419; 95% CI, 1.179-1.707), and safety of sports facilities (OR = 0.316; 95% CI, 0.614-0.865), influence children and adolescents' participation in soccer programs.

Betaine Alleviates LPS-Induced Chicken Skeletal Muscle Inflammation with the Epigenetic Modulation of the TLR4 Gene.

Betaine was found to alleviate inflammation in different studies. Here, newly hatched broilers were randomly divided into control and betaine consumptive groups, who had access to normal drinking water and water with betaine at a dose of 1000 mg/L, respectively. At the age of two weeks, the boilers were intraperitoneally treated with LPS. The protective effects of betaine against LPS-induced skeletal muscle inflammation were studied. Betaine attenuated the LPS-induced overexpression of IL-6 significantly in the leg muscle. Furthermore, LPS lowered the expression of TLR4 and TLR2 but increased the expression of MyD88. Betaine eliminated the effect of LPS on the expression of TLR4 but not TLR2 and MyD88. LPS also increased the expression of Tet methylcytosine dioxygenase 2 (Tet2), and this effect was also eliminated by betaine consumption. MeDIP-qPCR analysis showed that the methylation level in the promoter region of IL-6 was decreased by LPS treatment, whilst betaine cannot prevent this effect. On the contrary, LPS significantly increase the methylation level in the promoter region of TLR4, which was decreased by the consumption of betaine. Our findings suggest that betaine can alleviate LPS-induced muscle inflammation in chicken, and the regulation of aberrant DNA methylation might be a possible mechanism.

High Quality-Factor and Spectrum-Clean AlN Lamb-Wave Resonators with Optimized Lateral Reflection Boundary Conditions and Transducer Design.

This paper presents a high quality-factor (Q) and spectrum-clean AlN Lamb-wave resonator (LWR). The width of its lateral reflection boundary was optimized to weaken the transverse modes' coupling and wave guiding, and then to improve the LWR's Q value and spectral purity, which was verified by finite element analysis and experimental characterization. In addition, the series resonance quality factor (Qs) value of the interdigitated (IDT)-Ground LWR is similar to that of the IDT-Floating LWR, but its parallel resonance quality factor (Qp) is nearly doubled, due to the reduction of the electrical loss induced by its static capacitance (C0). The measured results show that the designed LWR with optimized boundary reflection conditions and IDT-Ground structure exhibit Qs and Qp values as high as 4019.8 and 839.5 at 401.2 MHz and 402.9 MHz, respectively, meanwhile, it has good spectral purity. Moreover, the influence of the metal ratio and material of the LWR's IDT electrodes on the device's performance was also studied by theoretical analysis and experimental verification.

Study on the Status of Scientific Fitness Literacy of Rural Left-Behind Minors and the Influence of Family Environment.

There are a large number of 6.97 million left-behind children in China at the end of August 2018. Left-behind children exhibit many psychologically unhealthy behavioural disorders. This study aimed to compare the differences in scientific fitness literacy (SFL) between rural left-behind and general minors, and to analyze the factors affecting the SFL of left-behind minors in the family environment. A random stratified sampling was conducted among minors aged 3-18 in rural areas of China, and 2239 valid samples were obtained. The questionnaire is based on the SFL part and the family environment part of the China National Fitness Activity Status Survey, except for the SFL part of the children's questionnaire does not contain the attitude dimension, the questionnaires of several other age groups contain three dimensions: attitude, skills, and habits. The SFL of general children and adolescents was higher than that of left-behind children and adolescents, and in the sub-dimensions, children's attitudes and adolescents' skills and habits differed greatly, with the general minors having better performance. The SFL showed a significant increasing trend with age in the general minors but the difference between children and adolescents in the left-behind minors was not significant. The scores of habituation in left-behind minors increased with age group, and the scores of the general minors group did not vary much between age groups. In the multiple regression analysis for the left-behind minors, it was found that left-behind young children were less influenced by family environment on SFL score, and children's SFL was more influenced by family environment. A separate analysis of the 7-9 and 10-12-year-old groups revealed that factors such as parental support and encouragement influenced SFL with different weights, and the importance of parents rotated, while the number of sporting goods in the family was important in all four age models. For the left-behind minors with a large amount in China, the role of the family environment in their SFL cannot be ignored, and the promotion of this literacy should be carried out in a targeted manner.