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SUMMARY: Heat is a critical environmental stress for plant survival. One of its harmful effects on the cells is the disruption of genome integrity. However, the mechanisms by which plants cope with heat‐induced DNA damage remain largely unknown. RMI1, a component of the RTR (RECQ4‐TOP3α‐RMI1) complex, plays a pivotal role in maintaining genome stability. In this study, we identified the target gene RMI1 by characterizing a high‐temperature‐sensitive mutant. The growth and development of rmi1‐1 seedlings carrying a non‐frameshift mutation in RMI1 were hindered at 38°C. Abnormal mitotic chromosome behaviours ultimately led to the cell death of root tips. Additionally, the presence of chromosome fragments during anaphase I caused pollen abortion and sterility in rmi1‐1 plants. Yeast two‐hybrid assays revealed that the interactions between RMI1‐1 and RECQ4 or TOP3α were weakened with increasing temperature and entirely ceased at 36°C. In contrast, the functional RMI1 maintained its interactions with RECQ4 or TOP3α under the same conditions. These results indicate that the non‐frameshift mutation in RMI1 disrupts the formation of the RTR complex at high temperatures, leading to defects in DNA repair and increased sensitivity of rmi1‐1 under heat stress. However, embryos of the rmi1‐cr2 mutant with a frameshift mutation in RMI1 exhibited complete lethality. In addition, the overexpression of RMI1 enhanced the heat tolerance in rice. These findings provide insights into the molecular mechanisms that RMI1 responds to high temperatures by maintaining genome stability in rice. Significance Statement: RMI1 is essential for rice growth and development at high temperature. [ABSTRACT FROM AUTHOR]

The fecal microbiota was studied in patients with inflammatory bowel disease (IBD), and the characteristics of gut microbiota were compared among patients with different subtypes and stages of IBD, aiming to identify the gut microbiota associated with IBD. Methods: Fecal samples were collected from 41 IBD patients (18 patients with ulcerative colitis [UC] and 23 patients with Crohn's disease [CD]) in the Department of Gastroenterology of East China Hospital, Fudan University between January 2021 and January 2022. In addition, fecal samples were collected from 20 healthy volunteers. The fecal microbiota was subjected to 16S rRNA gene sequencing, followed by bioinformatics analysis. Results: There was significant difference in the fecal microbiota between IBD patients and controls. The abundance and diversity of fecal microbiota in the IBD patients were significantly lower than in controls. The relative abundance of Subdoligranulum, Ruminococcus, Anaerostipes and Lachnospira was reduced markedly in the IBD patients. As compared to controls, the relative abundance of Streptococcus increased dramatically in the UC patients. The relative abundance of Lachnoclostridium, Fusobacterium, Cloacibacillus and Erysipelatoclostridium significantly increased in the CD patients. As compared to CD patients, the relative abundance of Alistipes was reduced markedly in the UC patients; the relative abundance of Faecalibacterium, Roseburia and Haemophilus was reduced dramatically in the CD patients. In addition, significant difference was also noted in the fecal microflora between patients with active IBD and those with IBD in remission period. In active IBD patients, the relative abundance of Roseburia, Coprococcus and Ruminiclostridium was reduced significantly. Conclusion: There is intestinal microbiota imbalance in IBD patients, and the abundance of Roseburia, Coprococcus and Ruminiclostridium is reduced significantly in the active period of IBD, which may be related to the active IBD. [ABSTRACT FROM AUTHOR]

An Extended Layerwise/Solid-Element (XLW/SE) method is developed based on the Extended Layerwise method (XLWM) and eight-node solid element method for the static analysis of damaged composite sandwich structures with piezoelectric sensor. In this method, the XLWM is used to model the facesheets and piezoelectric sensors, and the eight-node solid element is used for the lattice. Based on the equilibrium conditions of displacement and internal force of the overlapped joints at the facesheet/sensors and facesheet/lattice interfaces, the general governing equation is established. In the numerical examples, the proposed method is verified by comparing with the 3D elasticity model developed in the commercial finite element software, and composite sandwich plates with delamination and/or transverse crack and/or debonding are analyzed. [ABSTRACT FROM AUTHOR]

Liquid-phase shear exfoliation (LPSE) is a potential method of large-scale production of good-quality graphene. Obtaining few-layer (<10) graphene with large lateral sizes and high yields remains a challenging issue. Here, we report an improved LPSE processing method involving the addition of mica plates, which serve as bifunctional agents. With the addition of 100 g L−1 of mica, the LPSE (9000 rpm/0.24 mm/1 h) of expanded graphite offers ∼100% few-layer graphene with average lateral sizes (ALSs) of ∼2.8 μm and yields of up to 27% (the highest ever reported). The graphene produced by LPSE without any additives, however, contains only ∼77% few-layer nanosheets, and has ALSs of ∼1.3 μm and yields of 8%. Significantly, the addition of SiO2 microspheres as a comparison has almost no influence on the LPSE. The mica plates control the vector of fluids in LPSE and guide the oriented arrangement of the layered materials (e.g., expanded graphite), leading to significantly improved LPSE efficiency. 2D transition metal dichalcogenides (TMDs) with improved yields were also successfully prepared using LPSE with the addition of mica. [ABSTRACT FROM AUTHOR]