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[Objective] The Dabie Mountain area in western Anhui Province is an important ecological transition area between the Yangtze River Basin and the Huaihe River Basin in Anhui Province. The study on the landscape pattern and soil erosion and their relationship in this area is helpful to provide a reference for the regulation of landscape pattern and soil erosion control in this area. [Methods] The RULSE model was used to calculate the soil erosion modulus in the Dabie Mountains of western Anhui in the recent 30 years. The changes of landscape pattern were described by landscape index, and the influence of landscape index on soil erosion was explored by partial least squares regression (PLSR). [Results] In recent 30 years, the soil erosion modulus showed a trend of decreasing first and increasing later. The areas with serious soil erosion were mainly concentrated in the central and western regions and the southern mountainous areas. In most areas, the soil erosion intensity was mainly slight and mild, and the erosion intensity of different land use types had obvious difference, which was grassland > cultivated land > forest land. The land use type and landscape pattern were generally stable. The change of landscape pattern was mainly manifested in the reduction of landscape fragmentation and the improvement of landscape heterogeneity and connectivity. Shannon’s Diversity Index (SHDI), Edge Density Index (ED), Proportion of Like Adjacencies (PLADJ), and Landscape Shape Index (LSI) had significant explanatory significance for the Dabie Mountain area in west Anhui Province. Shannon’s Diversity Index (SHDI), Edge Density Index (ED), and Landscape Shape Index (LSI) had significant positive effects on soil erosion, while Proportion of Like Adjacencies (PLADJ) had significant negative effects on soil erosion. [Conclusion] In the Dabie Mountains of western Anhui, the increase of landscape fragmentation and the decrease of landscape connectivity will significantly promote soil erosion.

Anomaly propagation is a non-traditional mode of information dissemination that frequently occurs in today’s online social networks. To fully comprehend the overall process of anomaly propagation in social networks, the anomaly propagation lifecycle system was classified into incubation period, diffusion period, climax period, and decline period. In response to the scientific problems existing in different stages of anomaly propagation, four popular research fields of anomaly information, anomaly users, anomaly propagation, and propagation containment were defined and divided respectively from micro and macro perspectives. The main research tasks and related research progress in the four current research areas were reviewed and summarized in detail, problems in existing methods were analyzed. The future research directions on anomaly propagation in social networks were prospected, providing convenience for subsequent research.

The spin transfer tunnel magnetic tunnel junction (STT-MTJ) has been widely used in computers, memory, and other fields because of its nonvolatility, low power consumption, and high capacity for integration, attracting significant attention in recent years. Building an accurate and efficient magnetic tunnel junction (MTJ) behavior model is necessary to accurately describe the physical changes caused by variations in external excitation and guide the design and optimization of magnetic random access memory (MRAM). In this paper, we construct a multiphysical field dynamic behavior model of a perpendicular STT-MTJ, introducing temperature and frequency effects based on the Landau–Lifshitiz–Gilbert–Slinbczewski (LLGS) equation and a macro model. Compared with the LLGS model, our model simplifies the calculation of the tunneling current and shortens the simulation time by ~40%. Compared with the macro model, ours model can more accurately reflect the dynamic physical changes in magnetoresistance under a small signal and transient excitation. Simulation modeling and experimental comparison verify the temperature and frequency dependencies of the model. Our model provides guiding significance for the design, application, and research of MTJ devices’ electromagnetic compatibility characteristics.

Excessive fluoride intake poses health risks to humans and animals. Many studies have indicated that fluoride exposure can damage the cytoskeleton and synapses, which has negative effects on the intellectual development of humans and animals. Our previous study suggested that the RhoA/ROCK signalling pathway is activated by NaF exposure in HT-22 cells and plays a vital role in cytoskeletal assembly and synaptogenesis. However, the mechanism underlying RhoA/ROCK-mediated cytoskeletal injury induced by fluoride remains unclear. In this study, Neuro-2A cells and ICR mice were used to investigate the effects of RhoA/ROCK activation inhibition on NaF-induced synaptic dysfunction and cognitive impairment. We detected the expression of GAP, RhoA, ROCK1/2, and (p)-MLC in vivo and in vitro model. The results showed that NaF exposure activated the RhoA/ROCK/MLC signalling pathway. We measured the effects of RhoA/ROCK inhibition on synaptic injury and intellectual impairment induced by NaF exposure. In vitro, Y-27632 suppressed activated RhoA/ROCK, attenuated morphological and ultrastructural damage, and decreased the survival rate and synapse-functional protein expression caused by NaF. In vivo, the results showed that the RhoA/ROCK/MLC pathway was inhibited by fasudil and improved pathological damage in the hippocampus, cognitive impairment, and decreased expression of neurofunctional proteins induced by NaF. Overall, these results suggest that fasudil and Y-27632 can reverse neurotoxicity caused by fluoride exposure. Furthermore, inhibition of RhoA/ROCK may be a future treatment for CNS injury, and more detailed studies on other neurodegenerative disease models are required to confirm its effectiveness.

Due to the influence of multiple DC commutation failure after AC failure and stable interaction of system frequency, voltage and power Angle, the operation control of power grid is greatly difficult. The control scenario of multi-feed DC commutation failure or system instability is constructed, the comprehensive control performance cost ratio index of emergency control measures to the safety of multi-turn DC commutation and system stability is proposed, and the search method of coordinated control strategy based on global optimal is developed to avoid the risk of chain failure caused by negative control effects. The evaluation of control search path and control target after joint optimization is realized, which is conducive to the construction of system-level defense method and improves the adaptability of strategy.

BackgroundTobacco smoking and alcohol drinking are associated with several diseases, and studies on the joint effects of smoking and drinking are rare.ObjectiveThis study investigates the joint effects of tobacco smoking and alcohol drinking on all-cause and premature mortality in a contemporary cohort.MethodsThe China Health and Retirement Longitudinal Study (CHARLS) is an ongoing nationally representative survey of subjects aged over 45 years in China that was performed every two years for a total of three waves from 2011 to 2015 in China. We used weighted logistic regression models to estimate the joint effects of tobacco smoking and alcohol drinking on all-cause and premature mortality.ResultsAfter adjusting for prespecified confounders, the odds ratios (ORs) of all-cause mortality were 1.51 (95% CI: 1.09-2.10) and 1.47 (95% CI: 1.03-2.08) in smokers and smokers/drinkers, respectively. Compared with nonsmokers/nondrinkers, the OR of smokers/drinkers for premature death was 3.14 (95% CI: 1.56-6.34). In the female subgroup, there was an approximately 5-fold (OR = 4.95; 95% CI: 2.00-12.27) odds of premature mortality for smokers/drinkers compared to nonsmokers/nondrinkers.ConclusionThis study found a joint effect of tobacco smoking and alcohol drinking on all-cause and premature mortality among a contemporary and nationally representative cohort in China. Our results suggested that the joint effects were more pronounced in women, but further research is needed.

An adaptive dynamic sliding mode control method is proposed for the tracking of the expected trajectory of the ball and plate system. Considering the unpredictability of the external disturbance and the uncertainty in the actual situation,it combines with the adaptive control to estimate the unknown boundary. In order to effectively weaken the dependence on the mathematical model, the dynamic surface strategy is introduced to avoid the phenomenon of differential big explosion in inversion method. Considering whether there are any external uncertainties, the two experimental environments are divided into two kinds of experimental environment, and the simulation experiment is carried out using the method of this paper and the method of dynamic sliding mode. The simulation results show that the designed controller is not sensitive to system parameter perturbation and external disturbance.The method can realize the trajectory tracking of the ball well, and has good dynamic tracking performance, which shows strong robustness and adaptive characteristics.

The principle of double- flank gear measuring is usually adopted by gear screening equipment in workshop. The real quality of gear transmission cannot be obtained because of the test result containing manufacture error in both sides of tooth. To solve this problem,a new type of gear comprehensive roll testing method is studied,combining the gear double meshing gear radial comprehensive deviation detection with the single meshing vibration noise detection,the quality of gear transmission can be comprehensively evaluated. The key techniques,such as automatically aligning tooth,automatic backlash adjust,electric closed coupling loading,measuring and analysis are solved. The complement software is developed,which is applied on YKZ9932 machine manufactured by Tianjin No. 1 Machine Tool Works. According to the test result,the gear transmission quality is reflected more systematically by using this new method.