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The mechanism of hydrolysis and extension diffusion of heavy metal pollution elements infiltrated into rock is analyzed by the theory of ion hydrolysis displacement. The hydrolysis properties of typical elements such as cadmium, zinc, lead, and copper are verified by convective dispersion model, and the diffusion law and fission characteristics of heavy metal with different hydrolysis constant are discussed. A three-dimensional constitutive relation model of rock extension diffusion surface is established by combining viscoelastic monomer model with a damage monomer model. Considering the influence of diffusion coefficient, hydrolysis constant, deformation factor, and other parameters, the rationality of the test results and model fitting results of heavy metal invading rock are verified. The results show that the replacement rate of colloidal mineral elements in rock varies with different hydrolysis constant, when the hydrolysis constant is large, the extension diffusion rate in rock is large; otherwise, the extension diffusion rate is small. Constitutive relation curves of polluted rock with different lithologies are in good agreement with the fitting results of the combination model under the influence of the same test conditions and the same parameters.

A nationwide survey in China found that skin diseases are common among college students, with a prevalence rate of 60.1%. Acne was the most common skin disease, followed by eczema, androgenetic alopecia, chronic urticaria, and rosacea. The study estimated that the overall burden of skin disease was 667.0 years lived with disabilities (YLDs) per 100,000, with noncommunicable skin diseases accounting for the majority of the burden. The study emphasized the need for accurate data to inform policymakers and recommended prioritizing the prevention, screening, and management of noncommunicable skin diseases. [Extracted from the article]

Ankylosing spondylitis (AS) is a chronic immune-mediated inflammatory disorder involving the sacroiliac (SI) joints, the spine and often the hips. Biologic therapy has been shown to be efficacious in patients with AS and could improve patients' quality of life. With the increased use of tumor necrosis factor-ɑ (TNF-ɑ) inhibitors, more paradoxical reactions have been revealed. However, the treatment option for patients with AS is still a challenge when refractory paradoxical palmoplantar pustulosis appeared after the use of TNF-ɑ inhibitors. We reported the case of a 45-year-old male patient with AS treated with adalimumab treatment who developed a refractory paradoxical palmoplantar pustulosis after failure of prior secukinumab treatment. A dramatic improvement was seen in all skin and low back pain after the use of ixekizumab. We conclude that, in TNF-α inhibitors induced refractory paradoxical palmoplantar pustulosis, ixekizumab should be considered as an alternative option to choose from. [ABSTRACT FROM AUTHOR]

The successful implementation of high-level decision algorithm on quadrotor depends on the accurate trajectory tracking performance. In this paper attitude estimation and trajectory tracking control problem of quadrotor unmanned aerial vehicle (UAV) with endogenous and exogenous disturbance are considered, where the lumped disturbance characteristic does not have a probabilistic illustration but instead the dynamics are known to have a bound. The problem is handled by developing disturbance estimator and control strategy. In order to estimate lumped disturbance precisely, a globally finite time stable extended state observer is proposed based on super-twisting algorithm. Stability analysis and observer's parameters selection rule are discussed by using Lyapunov's stability theory. The proposed observer strategy achieves accurate observing performance of disturbance without increasing observer's order, and chattering effect is also reduced by applying super-twisting algorithm. Furthermore, a super-twisting sliding mode control law is proposed to guarantee the asymptotic convergence of the drone's orientation with respect to the reference. Finally, a numerical study based on simulations is presented to analyze the performance of proposed approach. [ABSTRACT FROM AUTHOR]