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Recently, two-dimensional (2D) magnets have drawn substantial attention from researchers for their fascinating properties and great application potential in the fields of biomedicine, data storage, signal transfer, and energy conversion. However, the low Curie/Néel temperature of 2D magnets hinders their application. In this Perspective, we present some physical insights into enhancing the magnetic stability of 2D magnets. First, the microscope theoretical model of 2D magnets is introduced. Then, we review and analyze several effective and commonly used methods for enhancing the magnetic stability of 2D magnets. Finally, we present the perspective and summary. This Perspective presents the advanced understanding of magnetic stability in 2D materials, which can provide new opportunities for further advancement in a wide variety of applications. [ABSTRACT FROM AUTHOR]

In recent years, the two-dimensional (2D) orthorhombic SiP2 flake has been peeled off successfully by micromechanical exfoliation and it exhibits an excellent performance in photodetection. In this paper, we investigated the mechanical properties and the origin of its anisotropy in an orthorhombic SiP2 monolayer through first-principles calculations, which can provide a theoretical basis for utilizing and tailoring the physical properties of a 2D orthorhombic SiP2 in the future. We found that the Young's modulus is up to 113.36 N/m along the a direction, while the smallest value is only 17.46 N/m in the b direction. The in-plane anisotropic ratio is calculated as 6.49, while a similar anisotropic ratio (~6.55) can also be observed in Poisson's ratio. Meanwhile, the in-plane anisotropic ratio for the fracture stress of the orthorhombic SiP2 monolayer is up to 9.2. These in-plane anisotropic ratios are much larger than in black phosphorus, ReS2, and biphenylene. To explain the origin of strong in-plane anisotropy, the interatomic force constants were obtained using the finite-displacement method. It was found that the maximum of interatomic force constant along the a direction is 5.79 times of that in the b direction, which should be considered as the main origin of the in-plane anisotropy in the orthorhombic SiP2 monolayer. In addition, we also found some negative Poisson's ratios in certain specific orientations, allowing the orthorhombic SiP2 monolayer to be applied in next-generation nanomechanics and nanoelectronics. [ABSTRACT FROM AUTHOR]

Objective To investigate the feasibility and safety of using diaphragmatic ultrasound to guide timing of laryngeal mask extraction during anaesthesia for laparoscopic inguinal hernia surgery in children. Methods A total of 140 children undergoing laparoscopic inguinal hernia repair surgery were selected, and the children were randomly divided into two groups : the group with laryngeal mask extraction guided by diaphragmatic ultrasound (Group D) and the group with laryngeal mask extraction guided by awake (group A). The two groups were instructed on the timing of laryngeal mask extraction according to different ways, and the incidence of adverse events, such as difficulty in pulling out, cough, laryngospasm, bronchospasm, and pharyngeal pain, were compared between the two groups during and after the extraction, the analysis compared the incidence and management of peripheral oxygen desaturation between the two groups. Results The rates of difficulty in pullout and laryngospasm in group D were both lower than those in group A, and the number of cases of adverse events in group D was lower than that in group A, the difference was statistically significant. The incidence of oxygen desaturation after removal of the laryngeal mask was lower in group D than in group A, and the difference was statistically significant. The time from the end of surgery to removal of the laryngeal mask and the steward awakening score up to 4 points in group D were shorter than those in group A, and the differences were statistically significant. Conclusion During awakening from anaesthesia for laparoscopic inguinal hernia surgery in children, monitoring the rate of change in diaphragmatic thickness with ultrasound can lead to better guidance in the extraction of laryngeal mask with a lower incidence of adverse effects and greater safety. [ABSTRACT FROM AUTHOR]

In this work, we explore the impacts of charge doping on the magnetism of a Cr2Ge2Te6 monolayer using first-principles calculations. Our results reveal that doping with 0.3 electrons per unit cell can enhance the ferromagnetic exchange constant in a Cr2Ge2Te6 monolayer from 6.874 meV to 10.202 meV, which is accompanied by an increase in the Curie temperature from ~85 K to ~123 K. The enhanced ratio of the Curie temperature is up to 44.96%, even higher than that caused by surface functionalization on monolayer Cr2Ge2Te6, manifesting the effectiveness of charge doping by improving the magnetic stability of 2D magnets. This remarkable enhancement in the ferromagnetic exchange constant and Curie temperature can be attributed to the increase in the magnetic moment on the Te atom, enlarged Cr-Te-Cr bond angle, reduced Cr-Te distance, and the significant increase in super-exchange coupling between Cr and Te atoms. These results demonstrate that charge doping is a promising route to improve the magnetic stability of 2D magnets, which is beneficial to overcome the obstacles in the application of 2D magnets in spintronics. [ABSTRACT FROM AUTHOR]