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Watershed water quality monitoring is of great significance in the protection and management of water environments. Because existing water quality prediction algorithms cannot achieve high-precision multiparameter analysis and usually require a large amount of data, this paper proposes the VARLST hybrid water quality prediction model. The proposed model combines the traditional statistical vector autoregressive moving average model and the bidirectional long short-term memory neural network to achieve multiparameter water quality data prediction on small data samples, and the model data processing is simple and highly efficient. This model is used to analyze the characteristics of water quality parameters in the Inner Mongolian section of the Yellow River Basin in northern China. The average error and fitting accuracy of the prediction results are 0.0015 and 99.869%, respectively; hence, the model achieves high-accuracy prediction of multiparameter indicators using less data, outperforming single models in terms of feasibility and accuracy. [Display omitted] • Multiparameter water quality prediction is realized, with comprehensive consideration of the correlations between data. • For cases in which the water quality data variation is not obvious, data prediction is realized for small samples. • The predictive model is lightweight and shows enhanced generalization capabilities. [ABSTRACT FROM AUTHOR]

During the damage and defects related to rolling contact fatigue (RCF), together with wear occurring at the rail surface, the microscopic characteristics of the rail material change with the accumulation of wheel cycles. To find the relationship between rail material characteristics and RCF damage under wheel-rail contact situations, a series of twin-disc rolling-sliding tests, based on real wheel-rail contact situations at a radius of 80 mm rail profile, was established for a heavy-haul railway in China. The microscale characteristics of the rail disc contact surface was researched, including crack, wear, roughness, and hardness of the U75V rail with different load cycles. The results show that the damage mechanism of RCF and wear alternately dominates the rail disc surface at the microscale, taking a certain cycle as a boundary which makes the RCF crack number and wear rate have opposite evolutionary trends. The above factors also affect the wear at the surface rail discs, alternating between fatigue and adhesion. Meanwhile, increasing the surface micro-hardness leads to a decrease in the relative wear rate and an increase in the roughness, length and number of RCF cracks. The plastic deformation layers, including the severely deformed layer (SDL) and the transition layer (TL), almost maintain the same thickness and the dynamic equilibrium increases during the cycles. Two kinds of cracks are initiated and propagated at the rail disc surface, one at the SDL and the other at the junction of SDL and TL. The number of each kind of crack depends on the SDL thickness. • The RCF and wear mechanisms dominated the rail surface alternately by a certain cycle. • Increasing the microhardness makes wear decreasing followed by an increase in roughness and RCF cracks. • The adhesive and fatigue wear happened alternately during the cycles. • The fracture mode of along or through the crystal depends on plastic deformation layer. • The thickness of the severely deformed and transition layers changes on opposite while keeps the entire thickness constant. [ABSTRACT FROM AUTHOR]

Aim: To evaluate the clinical efficacy and safety of acupuncture and moxibustion for the treatment of active Crohn's disease (CD)., Methods: Ninety-two patients were equally and randomly divided into the treatment group and received herb-partitioned moxibustion combined with acupuncture, and the control group received wheat bran-partitioned moxibustion combined with superficial acupuncture. The patients received three treatment sessions per week for 12 wk and were followed up for 24 wk. The main outcome was evaluated using the CD Activity Index (CDAI) score, and the secondary outcomes were evaluated using laboratory indicators such as hemoglobin (HGB), C-reactive protein (CRP), erythrocyte sedimentation rate, quality-of-life, endoscopic ratings, and intestinal histology scores., Results: The CDAI scores of both the treatment and control groups were significantly reduced after treatment compared with those measured before treatment. However, the degree of improvement in the treatment group was significantly greater than that of the control group. The improvement in symptoms in patients of the treatment group was sustained at follow-up, whereas that of the control group was not. The overall efficacy of the treatment was significantly greater than that of the control. Both groups demonstrated significant improvements in quality-of-life ratings after treatment, but the improvement was significantly greater in the treatment group than in the control group. In addition, the patients in the treatment group showed significantly increased HGB and significantly decreased CRP levels and histopathological scores at the end of treatment, whereas the control group did not exhibit significant changes., Conclusion: Moxibustion with acupuncture provided significant therapeutic benefits in patients with active CD beyond the placebo effect and is therefore an effective and safe treatment for active CD.