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Background: The incidence of osteochondral defects caused by trauma, arthritis or tumours is increasing annually, but progress has not been made in terms of treatment methods. Due to the heterogeneous structure and biological characteristics of cartilage and subchondral bone, the integration of osteochondral repair is still a challenge. Results: In the present study, a novel bilayer hydrogel scaffold was designed based on anatomical characteristics to imitate superficial cartilage and subchondral bone. The scaffold showed favourable biocompatibility, and the addition of an antioxidant nanozyme (LiMn2O4) promoted reactive oxygen species (ROS) scavenging by upregulating antioxidant proteins. The cartilage layer effectively protects against chondrocyte degradation in the inflammatory microenvironment. Subchondral bionic hydrogel scaffolds promote osteogenic differentiation of rat bone marrow mesenchymal stem cells (BMSCs) by regulating the AMPK pathway in vitro. Finally, an in vivo rat preclinical osteochondral defect model confirmed that the bilayer hydrogel scaffold efficiently promoted cartilage and subchondral bone regeneration. Conclusions: In general, our biomimetic hydrogel scaffold with the ability to regulate the inflammatory microenvironment can effectively repair osteochondral defects. This strategy provides a promising method for regenerating tissues with heterogeneous structures and biological characteristics. [ABSTRACT FROM AUTHOR]

Background: The incidence of osteochondral defects caused by trauma, arthritis or tumours is increasing annually, but progress has not been made in terms of treatment methods. Due to the heterogeneous structure and biological characteristics of cartilage and subchondral bone, the integration of osteochondral repair is still a challenge. Results: In the present study, a novel bilayer hydrogel scaffold was designed based on anatomical characteristics to imitate superficial cartilage and subchondral bone. The scaffold showed favourable biocompatibility, and the addition of an antioxidant nanozyme (LiMn2O4) promoted reactive oxygen species (ROS) scavenging by upregulating antioxidant proteins. The cartilage layer effectively protects against chondrocyte degradation in the inflammatory microenvironment. Subchondral bionic hydrogel scaffolds promote osteogenic differentiation of rat bone marrow mesenchymal stem cells (BMSCs) by regulating the AMPK pathway in vitro. Finally, an in vivo rat preclinical osteochondral defect model confirmed that the bilayer hydrogel scaffold efficiently promoted cartilage and subchondral bone regeneration. Conclusions: In general, our biomimetic hydrogel scaffold with the ability to regulate the inflammatory microenvironment can effectively repair osteochondral defects. This strategy provides a promising method for regenerating tissues with heterogeneous structures and biological characteristics. [ABSTRACT FROM AUTHOR]

Summary: The development of a series of elite maize hybrids has greatly increased crop yield in the past decades. Parental lines of these hybrids usually come from different heterotic groups and contain many genetic differences. Identifications of important quantitative trait genes in the elite hybrids can extend our understanding of heterosis and also help to guide genetic improvement.Here, we mapped a major quantitative trait locus using a linkage population from an elite maize hybrid Zhengdan958 and identified ZmLNG1 as the causative gene controlling multiple morphologic traits in maize. A 6‐kb deletion in one parental line of the hybrid leads to the fusion of ZmLNG1 with its nearby gene. The fusion event prevents the C‐terminal of ZmLNG1 from interacting with ZmTON1, which resulted in the change of plant architecture.Further experiments demonstrated that ZmLNG1 could act as a mediator to connect ZmTON1 and ZmOFPs, which belong to another type of plant morphological regulatory proteins, thereby affecting the phosphorylation level of ZmOFPs.These results demonstrate the importance of ZmLNG1 in forming the TON1‐TRM‐PP2A complex and provide a model for the regulation of plant organ morphology by TON1‐recruiting motifs (TRMs) and Ovate family proteins (OFPs). [ABSTRACT FROM AUTHOR]

In this paper, the three failure modes of pipes were summarized and the molecular mechanism and fracture mechanics mechanism of slow crack growth were briefly described. The principle and test process of the strain hardening modulus (SH) method were introduced in detail. The paper also reviewed the research progress in the correlation of material microstructures, the domestic and foreign reliability research of SH method for the evaluation of the slow crack growth resistance of pipes, and the application of SH method for the evaluation of the environmental stress cracking resistance of materials. Finally, the applications of SH method for the control of outlook on product quality was discussed. [ABSTRACT FROM AUTHOR]

When driving a 32‐m long multi‐set rubber‐tire transit in a manual driving mode, it is easy for the driver to feel tired due to the massive concentration, and it is hard to manually operate in a narrow and twist gauge. The authors introduce a six‐axle coordinated automatic all‐wheel steering control system and its design method is based on the visual perception and the geometric relationship. First, the functions of the two subsystems of the full‐axle automatic steering control system are introduced. One subsystem is a path tracking control system and the other subsystem is a trajectory following the control system. Secondly, the theoretical principles of the two control systems are introduced in detail. Then, the controller design method of the two subsystems is introduced. Finally, the simulation results of Trucksim and MATLAB/Simulink are compared with the actual vehicle test data to test the controller's perception and the follow‐up control effect. It can be concluded that the gap between the platform and the train is kept between a relatively 10∼20 cm narrow when the train pulls in and out of the station. When the train runs at a high speed, it is stabilised at 72 km/h, and the lateral deviation from the virtual track centreline is controlled within ±15 cm. [ABSTRACT FROM AUTHOR]

This paper investigates the problem of event-based disturbance compensation control for discrete-time surface-mounted permanent magnet synchronous motor (SPMSM) subject to both mismatched external disturbances and the limited communication bandwidth. The mismatched external disturbances make it impossible to transform the original model into the multiple-step-ahead predictor model by using the existing predictor technology. To tackle such a challenge, a novel backstepping-based disturbance compensation control framework is firstly proposed for the discrete-time SPMSM with known system dynamics. In the proposed framework, the disturbance observer is designed to compensate for the external disturbances, and the novel variable substitution/decoupling technology is proposed to design the event-based controller for the original controlled system. The proposed controller is composed of the event-based feedback control signal and the feedforward disturbance compensation signal, thereby improving the system disturbance rejection ability and mitigating the communication resource. Subsequently, an event-based adaptive neural control scheme is proposed by combining a modified neural disturbance observer. The proposed scheme ensures that the tracking error converges to a small neighbourhood of the origin, all the signals in the closed-loop system are bounded and meanwhile the communication resources are greatly reduced. The effectiveness of the proposed controller is illustrated through the simulation results. [ABSTRACT FROM AUTHOR]