Aquatic exercise enhanced muscle strength in paretic lower limbs and improved muscle cocontraction without increasing spasticity in subacute stroke patients.

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Hepatic fibrosis is resulted from sustained wound-healing responses to various harmful stimuli, including viral infection, drug toxicity, alcohol, and autoimmune hepatopathy, and it has recently attracted the attention of an increasing number of researchers and clinical workers. The aims of this study were to examine the anti-fibrotic effects of extracts of Periplaneta americana (EPA) on CCl4-induced hepatic fibrosis in rats, to preliminary determine the anti-fibrotic efficacy of EPA, and to identify a potential and effective therapeutic agent to attenuate hepatic fibrosis. In this study, we routinely detected liver functional indices, such as alanine aminotransferase (ALT), aspartate transaminase (AST), and albumin (Alb). We also measured hepatic fibrosis-related serum markers, including hyaluronic acid (HA), laminin (LN), type III procollagen (PC III), and type IV collagen (IV-C) via radioimmunoassay. Moreover, we examined histological activity and fibrosis stage via light microscopy after hematoxylin and eosin and Masson staining. Furthermore, we detected the expressions of nuclear factor-kappa B (NF-κB), alpha-smooth muscle actin (α-SMA), transforming growth factor-β1 (TGF-β1), and tissue inhibitor of metalloprotease-1 (TIMP-1) in rat liver tissues by immunohistochemical staining. We found that EPA, whose main components are viscous sugar amino acids, can reduce the levels hepatic fibrosis-related factors, including HA, LN, PC III, and IV-C, improve liver function, attenuate, or reverse pathological damage associated with hepatic fibrosis, and thus inhibit the progression of hepatic fibrosis. The mechanism of EPA action may be related to the inhibition of TGF-β1, NF-κB, and α-SMA expressions and the reduction of TIMP-1 levels in the liver to reduce the accumulation of extracellular matrix (ECM) components, thereby blocking the relevant signaling pathways and preventing inflammatory responses to attenuate or reverse hepatic fibrosis. EPA may thus be used as a potentially effective therapeutic agent for the treatment of hepatic fibrosis.

The deep-mining coal seam impacted by high in situ stress, where Klinkenberg effects for gas flow were very obvious due to low gas permeability, could be regarded as a porous and tight gas-bearing media. Moreover, the Klinkenberg effects had a significant effect on gas flow behavior of deep-mining coal seam. Based on the gas flow properties of deep-mining coal seams affected by in situ stress field, geothermal temperature field and geoelectric field, a new mathematical model of coalbed gas flow, which reflected the impact of Klinkenberg effects on coalbed gas flow properties in multi-physical fields, was developed by establishing the flow equation, state equation, and continuity equation and content equation of coalbed gas. The analytic solution was derived for the model of one-dimensional steady coalbed gas flow with Klinkenberg effects affected by in situ stress field and geothermal temperature field, and a sensitivity analysis of its physical parameters was carried out by comparing available analytic solutions and the measured values. The results show that the analytic solutions of this model of coalbed gas flow with Klinkenberg effects are closer to the measured values compared to those without Klinkenberg effects, and this model can reflect more accurately gas flow of deep-mining coal seams. Moreover, the analytic solution of this model is more sensitive to the change of Klinkenberg factor b and temperature grad G than depth h.Keywords Porous media · Klinkenberg effects · Multi-physical fields · Mathematical model of coalbed gas flow · Analytic solution Nomenclature A Ash of coal a Langmuir volume parameter, m 3 kg −1 123 408 G. Hu et al. b Klinkenberg factor, Pa c Langmuir pressure parameter, Pa −1 C 1 , C 2 Integral constant D 0 Gas diffusion coefficient when the pore pressure equals p 0 d Average coal micro-grain size of coal seam, m div Divergence of a vector E Electric intensity grad Gradient of a scalar h Depth, m K g Gas permeability of coal, m 2 K ∞ Absolute gas permeability under very high pressure, m 2 k σ 0 Value of K σ (0) when effective stress σ equals zero k T 0 Value of K T (0) when the temperature of coal theoretically equals zero L Oblique length of coal seam, L = h/ sin θ , m m Methane content reserved in the unit volume coal, m 3 m −3 m 0 Gas content in coal seam at initial time t 0 , m 3 m −3 m a Absorbed gas content in coal seam, m 3 m −3 m d Desorbable average gas content in coal seam, m 3 m −3 m f Free gas content, m 3 m −3

Metro door system (MDS) is one of the most important and fault-prone parts of metro train. Reliability-centered maintenance (RCM) is a systematic engineering process for determining the preventive maintenance requirements of equipment and optimizing the maintenance system. This paper is motivated to apply RCM to the maintenance of metro door system. Firstly, the subsystems and components of MDS are introduced. Then a fuzzy FMECA method is proposed to define the hazard degree of 10 failure modes from 5 components with high failure rate to conduct reliability analysis. Finally, reliability-centered maintenance strategy is made after maintenance mode decision and calculation of maintenance interval cycle, which provides theoretical basis to the maintenance of the metro train.

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Protective coal layer (PCL) mining is a preferred regional method for preventing coal and gas outbursts; stress‐relief of PCL mining is the prerequisite of pressure‐relief gas drainage. In order to study the stress‐relief effect of PCL mining on protected coal seams and determine the protection scope of PCL mining under different inclinations, this paper uses physical simulations to study the stress‐relief law and deformation characteristics of the strata during upper PCL mining with a gentle inclination (25°), an intermediate inclination (45°), and a steep inclination (65°). The results show that as the coal seam dip increases, the degree of deformation and failure of the overburden strata gradually decreases, the severe subsidence and expansion area of the overburden strata tends to gradually develop in the uphill direction of the working face, and the floor strata underlying the protective seam significantly expand toward the goaf. However, the absolute value of the upward movement of the floor strata is much smaller than that of the roof strata; and the greater the dip angle, the greater the ratio of floor displacement to roof subsidence. The stress‐relief curve of the protected layer is approximately U‐shaped. As the inclination of the coal seam increases, the stress‐relief range decreases gradually. The maximum relief‐stress and the stress release coefficient of the protected layer initially increase and then decrease. The stress concentration coefficient of the protected coal seam initially increases first and then decreases in both uphill and downhill of the working face in the PCL. As the inclination increases, the stress‐relief angle of the downhill boundary initially increases and then decreases, while the stress‐relief angle of the uphill boundary decreases gradually. Our research results provide guidance for the delimitation of the protected scope of PCLs with different dip angles.