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Objective To investigate the effect and underlying mechanism of roxadustat on apoptosis and senescence of renal tubular epithelial cell line HK-2 induced by heat stress. Methods After HK-2 cells were treated with different concentrations of roxadustat (10, 20, 30, 40 and 50 μmol/L) for 24 h, CCK-8 assay was used to determine the optimal intervention concentration of roxadustat. HK-2 cells were divided into 4 groups (n=3): control group, roxadustat group (30 μmol/L, 24 h), heat-stress group (43 ℃, 2 h), and heat-stress+roxadustat group (30 μmol/L roxadustat treatmnet for 24 h followed by heat-stress 2 h). Cell viability was detected by CCK-8 assay. Expression of hypoxia-inducible factor-1α (HIF-1α), Cleaved Caspase-3, p16 and p21 at protein level was detected by Western blotting. Immunofluorescence assay was employed to observe the distribution of HIF-1α. β-galactosidase staining kit was utilized to detect SA-β-Gal activity. TUNEL staining was used to measure cell apoptosis. Results The highest cell viability was observed in the cells after 30 μmol/L roxadustat treatment. Heat stress resulted in a significant decrease in cell viability (P < 0.05), elevated protein levels of HIF-1α, Cleaved Caspase-3, p16 and p21(P < 0.05), enhanced SA-β-Gal activity (P < 0.05) and increased percentage of TUNEL-positive cells (P < 0.05) when compared with the cells in the control group. In comparison with the heat-stress group, the heat-stress+roxadustat group showed significant decrease in the protein levels of Cleaved Caspase-3, p16 and p21 (P < 0.05), reduced activity of SA-β-Gal [(65.44±5.00)% vs (77.15±2.61)%, P < 0.05] and decreased percentage of TUNEL-positive cells [(16.73±2.20)% vs (46.40±13.87)%, P < 0.05], but increase in cell viability [(86.33±4.51)% vs (66.33±8.50)%, P < 0.05] as well as HIF-1α protein expression (P < 0.05). Furthermore, immunofluorescence assay showed that HIF-1α was mainly distributed in the nucleus and perinucleus. Conclusion Roxadustat attenuates heat stress-induced apoptosis and senescence of renal tubular epithelial cells by upregulating HIF-1α.

Blasting vibration monitoring and analysis are the basis and premise of the research on the control of blasting vibration damage.Taking the blasting excavation of small spacing tunnel as the engineering background,Matlab was used to decompose the blasting vibration signals by 5 layers of wavelet packet transformation to obtain the wavelet packet frequency band energy of each node.The frequency band energy distribution characteristics of blasting vibration signal was studied,and the attenuation equation of total energy was proposed by regression analysis of total energy.The research shows that the energy of blasting vibration signal is mainly concentrated in the low frequency band(0~300 Hz).The higher the blasting vibration energy is,the faster the attenuation is.At the same time,energy exhibits that high frequency part attenuates faster and the low frequency part attenuates slower.Energy has a tendency toward low frequency with the increase of distance.The energy attenuation coefficient is twice of the peak velocity attenuation coefficient.When the distance from explosion center is in the range 0 to 30 m,energy attenuates rapidly,and energy attenuation tends to be gentle in the range of 30~53.5 m,while energy is almost zero after more than 53.5 m.The research results have important significance for the further study on the dynamic stability of the existing highway tunnels.

To study the ground pressure features of roadway under close range goaf，deformation laws of surrounding rock during mining are analyzed by deformation monitoring.Variations of vertical stress in surrounding rock during mining are obtained by numerical simulation.The results show that the convergence between roof and floor can be 2.02-3.09 times that between two side walls.The intense influence area is 10 m front of working face，where deformation velocity can become fast.The two side walls are influenced more significant in this area.Vertical stress in surrounding rock closed to coal pillar increases when adjacent to the working face.It can be found that the existence of goaf make curves no longer obey exponential function to the base.Working face under goaf has incomplete roof.So effects of abutment pressure decrease.The influence scope of abutment pressure is only 5-10 m，which reduces obviously compared to common roadway.The formation of side abutment pressure in upper coal pillars make a roadway under goaf has a larger deformation，and side walls supports are easy to damage because of a compressive expansion in surrounding rock.Roof sinking caused by the damage of support in side walls，and the seepage from goaf will aggravate the heave of Al-mudstones floor.

As the decision-making brain for power system operation, grid regulation and operation is a comprehensive decision-making control that combines a large amount of data, mechanism analysis, operating procedures and professional experience, and a new generation of artificial intelligence development ideas and evolution characterized by data-driven and knowledge-guided. The directions are very close. However, the current scheduling control is still based on experience and manual analysis. The massive and diverse data of the control center and the lack of logical models between the plans require a large amount of experience and knowledge associations by the control personnel. There are more repetitive human brain labor and relatively low intelligence. Therefore, deep learning is applied to the learning of power control knowledge, and a semantic understanding network based on deep Long Short Term Memory is proposed. It uses sequence labeling to extract in-depth semantic related information of different keywords and query questions, and finds key information about language problems in order to achieve fine-grained and precise query. Experiments show that the proposed network model is superior to the previous methods, and it achieves better performance in the joint extraction of fine-grained evaluation words and evaluation objects, extracts the key information and deep semantic information of query problems and corresponding cases, and realizes power scheduling based on voice interaction The model can be effectively applied in the field of power dispatching and solve a large number of problems in power dispatching and control. [ABSTRACT FROM AUTHOR]

The oxidation of Fe2+ by Acidithiobacillus ferrooxidans (A. ferrooxidans) in acid mine drainage (AMD) is often accompanied by formation of iron hydroxysulfate minerals, such as schwertmannite and jarosite. This study reported that 80 mmol L−1 of Fe2+ could be completely oxidized by A. ferrooxidans LX5 within 48 h, but only 27.7% of the resultant Fe3+ precipitated to form schwertmannite. However, the conversion efficiency to jarosite was much higher (54.5%). The formation of jarosite lasted 120 h, while only 24 h when conversed to schwertmannite. By constructing a cyclic process of 'Cu-reducing coupled with bio-oxidization', the total Fe in AMD could be fully converted into mineral precipitates. The resultant mineral specie could be regulated simply by control the K+ concentration. Thermodynamically, Fe3+ cannot hydrolyze spontaneously to form schwertmannite due to the positive Gibbs free energy ( Δ r G m ∘ = 6.63 kJ mol−1) of the reaction. However, if Fe2+ were biologically oxidized by A. ferrooxidans, the resultant Fe3+ could spontaneously form schwertmannite because the aforementioned coupling reaction has a negative Gibbs free energy ( Δ r G m ∘ = −34.12 kJ mol−1). Even though Fe3+ itself could hydrolyze to form jarosite spontaneously with Δ r G m ∘ = −22.20 kJ mol−1, the coupling reaction of Fe2+ bio-oxidation followed by Fe3+ hydrolysis in the presence of K+ could easily promote the formation of jarosite, which exhibited a great negative Gibbs energy ( Δ r G m ∘ = −67.45 kJ mol−1). [ABSTRACT FROM AUTHOR]

The Co‐modified CeO2‐TiO2 catalyst prepared by facile co‐precipitation was used for efficient elemental mercury oxidation in flue gas. Results indicated that Co doping greatly enhanced the activity and SO2 resistance of the CeO2‐TiO2 catalyst. In the presence of 5% O2, 500 ppm NO, 800 ppm SO2 and 3% H2O at 200 °C, the Hg0 removal efficiency of CeCo3/Ti could maintain at about 87% for a relatively long time. Characterizations of catalysts (BET, XRD, Raman spectroscopy, TEM, H2‐TPR, O2‐TPD, XPS, TG‐MS and SO2‐DRIFTS) were carried out to reveal the mechanism of Co modification on the redox ability, SO2 resistance and resultant mercury oxidation removal performance of catalyst. It was found that an interaction of Ce with Co promoted the dispersion of CeO2, increased chemisorbed oxygen concentration, and improved the oxygen storage capacity and the reducibility of catalyst, which was beneficial to the improvement of Hg0 oxidation removal. Hg0 would adsorb onto the catalyst and react with surface active oxygen species replenished by gas‐phase O2 to be oxidized via Mars‐Maessen mechanism. SO2 consumed the surface active oxygen species and resulted in the reduction of Ce4+ to Ce3+, which induced the deactivation of catalyst. The introduced Co in CeO2‐TiO2 catalyst exerted the function of protecting Ce4+ from being poisoned by SO2 and thus promoted the sulfur resistance and Hg0 removal performance of the catalyst in the presence of SO2. [ABSTRACT FROM AUTHOR]