Synthetic responses of plant and soil microbial communities to grazing are indefinite in alpine grasslands on the Tibetan Plateau. Three paired, fenced and free grazing sites (alpine steppe meadow for winter pasture [ASMWP]; alpine steppe meadow for summer pasture [ASMSP]; alpine meadow for summer pasture [AMSP]) were used to compare how pasture season and grassland type affect responses of the α‐diversity and community composition of plant, soil bacteria and fungi to grazing. Cold‐season grazing reduced soil moisture by 12.10%, ammonium nitrogen (NH4+‐N) by 53.71%, the ratio of available nitrogen to phosphorus by 64.11%, species richness (SR) by 31.4% and the Shannon by 11.9% of plant community on the ASMWP. Warm‐season grazing reduced nitrate nitrogen by 30.45%, SR of soil bacterial community by 21.98% on the ASMSP, but increased soil NH4+‐N by 90.02% on the AMSP. Warm‐season grazing‐induced changes in plant community composition were mainly related to the composition of forbs on the AMSP. Grazing‐induced changes in the community composition of soil bacteria were mainly related to Proteobacteria, Acidobacteria, Bacteroidetes, Firmicutes and Verrucomicrobia on the ASMWP, and Proteobacteria, Acidobacteria, Bacteroidetes, Chloroflexi and TM7 on the ASMSP. Grazing‐induced changes in the community composition of soil fungi were mainly related to Ascomycota and Basidiomycota on the ASMWP, Basidiomycota on the ASMSP and Ascomycota on the AMSP. Therefore, the effects of grazing on plant and soil microbial communities may vary with grassland types and pasture seasons, which may be related to grazing‐induced changes in available nitrogen, the ratio of available nitrogen to phosphorus and soil moisture.

Memory impairments are associated with many brain disorders such as autism, Alzheimer’s disease, and depression. Forming memories involves modifications of synaptic transmission and spine morphology. The Rho family small GTPases are key regulators of synaptic plasticity by affecting various downstream molecules to remodel the actin cytoskeleton. In this paper, we will review recent studies on the roles of Rho proteins in the regulation of hippocampal long-term potentiation (LTP) and long-term depression (LTD), the most extensively studied forms of synaptic plasticity widely regarded as cellular mechanisms for learning and memory. We will also discuss the involvement of Rho signaling in spine morphology, the structural basis of synaptic plasticity and memory formation. Finally, we will review the association between brain disorders and abnormalities of Rho function. It is expected that studying Rho signaling at the synapse will contribute to the understanding of how memory is formed and disrupted in diseases.

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Stellite 6 alloy has excellent wear resistance, corrosion resistance, and oxidation resistance, however the difficulties in traditional processing limit its wide application. Additive manufacturing technology that has emerged in recent years is expected to provide a new way for the processing of stellite 6 alloy. In this study, two square thin-walled stellite 6 parts were fabricated through the wire arc additive manufacturing technology. At the same time, the effect of stress relief annealing on the mechanical performance of the fabricated stellite 6 part was studied and compared with the corresponding casting part. The results indicate that the additive manufacturing stellite 6 components exhibit satisfactory quality and appearance. Moreover, the microstructure of the additive manufacturing part is much finer than that of the casting part. From the substrate to the top region of the additive manufacturing part, the morphology of the dendrites changes from columnar to equiaxed, and the hardness increases firstly and then decreases gradually. In addition, the average hardness of the additive manufacturing part is ~7–8 HRC higher than the casting part. The ultimate tensile strength and yield strength is ~150MPa higher than the casting part, while the elongation is almost the same. The stress relief annealing has no significant effect on the hardness of the AM part, but it can slightly improve the strength.

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Background Pathological retinal angiogenesis resulting from a variety of ocular diseases including oxygen induced retinopathy, diabetic retinopathy and ocular vein occlusion, is one of the major reasons for vision loss, yet the therapeutic option is limited. Multiple nanoparticles have been reported to alleviate angiogenic retinopathy. However, the adverse effect cannot be ignored due to the relatively large scale. Graphene quantum dots (GQDs) have shown potential in drug delivery and have been proved biocompatible. In this study, Graphene quantum dots are extensively investigated for their application in angiogenic retinopathy therapy. Results We showed that GQDs were biocompatible nanomaterials in vitro and in vivo. The nanoparticles have a dose-dependent inhibitory effect on proliferation, migration, tube formation and sprouting of human umbilical vein endothelial cells (HUVECs). Further data show that GQDs could inhibit pathological retinal neovascularization in an oxygen-induced retinopathy (OIR) model. The data of RNA sequencing suggested that periostin is involved in this process. GQDs inhibit the expression of periostin via STAT3, and further regulated cell cycle-related protein levels through ERK pathway. The signaling pathway was conformed in vivo using OIR mouse model. Conclusions The present study indicated that GQDs could be a biocompatible anti-angiogenic nanomedicine in the treatment of pathological retinal neovascularization via disrupting periostin/ERK pathway and subsequent cell cycle. Graphical Abstract

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