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Objective To explore the expression profile and role of hepatic long non-coding RNA (lncRNA) in acetaminophen-induced liver injury mouse model by analyzing lncRNA-mRNA co-expression. Methods Serum aminotransferase, liver pathology and inflammatory cells were analyzed in mice model at different time points after treated with acetaminophen 300 mg/kg. High-throughput RNA sequencing was performed to investigate hepatic expression profiles of messenger RNA (mRNA) and lncRNA. The relationship between the lncRNA and mRNA was delineated by the co-expression network using Cytoscape software. Differential mRNAs co-expressed with lncRNAs were analyzed using Gene Ontology and the Kyoto Encyclopedia of Genes and Genomes enrichment. Differential mRNAs and lncRNAs were selected for quantitative reverse transcription polymerase chain reaction validation, and the conservation of lncRNA between human and mouse was analyzed. Results Liver injury was more severe at 24 hours than at 6 hours. There was a substantial infiltration of monocytes instead of neutrophil and Kupffer cells at 24 hours compared with 6 hours. The mRNAs co-expressed with the differential lncRNAs at 24 vs 6 hours were mainly enriched in protein processing in endoplasmic reticulum, MAPK and PPAR signaling pathways. The co-expression network delineated with four lncRNAs and 94 mRNAs presented the core position of lncRNA in the network. A conservation analysis indicated that four differential mouse lncRNAs (NONMMUT023651.2, NONMMUT029382.2, NONMMUT029383.2 and NONMMUT102053.1) could all be mapped to the relevant human lncRNAs. Conclusion Four lncRNAs may play regulatory roles through metabolic and apoptosis-related pathways during hepatic homeostasis maintenance and repair progress.

Post-transplant lymphoproliferative disorder (PTLD) is a lethal complication after pediatric liver transplantation, but information regarding risk factors for the development of PTLD remains unclear. This study was to identify characteristics and risk factors of PTLD.A total of 705 pediatric patients who underwent liver transplantation between January 2017 and October 2018 were studied. Impact of clinical characteristics and Epstein-Barr virus (EBV) infection on the development of PTLD was evaluated. In addition, ImmuKnow assay was adopted in partial patients to analyze the immune status.Twenty-five (3.5%) patients suffered from PLTD with a median time of 6 months (3-14 months) after transplantation. Extremely high tacrolimus (TAC) level was found in 2 fatal cases at PTLD onset. EBV infection was found in 468 (66.4%) patients. A higher peak EBV DNA loads (9590 copies/mL) within 3 months was a significant indicator for the onset of PTLD. In addition, the ImmuKnow assay demonstrated that overall immune response was significantly lower in patients with EBV infection and PTLD (P0.0001). The cumulative incidence of PTLD was also higher in patients with lower ATP value (≤187 ng/mL, P0.05).A careful monitoring of EBV DNA loads and tacrolimus concentration might be supportive in prevention of PTLD in pediatric patients after liver transplantation. In addition, application of the ImmuKnow assay may provide guidance in reducing immunosuppressive agents in treatment of PTLD.

Orthogonal experiments of ultrasonic deep rolling with Longitudinal-torsional vibration (UDR-LTV) and conventional deep rolling (CDR) Q235 steel were carried out to study the effects of processing parameters on surface roughness. The orthogonal experiments results show that the influence laws of processing parameters on surface roughness are the same, and the values of surface roughness obtained by UDR-LTV are smaller than that of CDR with the same processing parameters. The values of surface roughness obtained by UDR-LTV and CDR increase and then decrease with the increment of the static pressure; and increase with the increment of the feed-rate, and change a little along with the increment of the rolling speed. Meanwhile, the feed-rate has a marked effect on the surface roughness, while the rolling speed has a little effect on the surface roughness. The quadratic regression method is used to construct the mathematic model to predict surface roughness based on the experimental results. The effects of parameter interactions on surface roughness are studied. The research shows that the interaction effects of the rolling speed and the feed-rate, the static pressure and the feed-rate on surface roughness are obvious, but the interaction effect of the static pressure and the rolling speed on surface roughness is not significant. The optimal parameters for the lowest surface roughness are given by the result of orthogonal design and prediction model, which has guiding significance for the application of ultrasonic surface strengthening technology with complex vibration mode.

The mechanism of longitudinal-torsional vibration (LTV) realized by using converter with multiple diagonal slits (MDS) was analyzed based on the acoustic wave propagation when acoustic wave enters obliquely from steel to air. The influences of geometrical parameters of the stepped compound horn with multiple diagonal slits on natural frequencies of LTV were studied with finite element analysis (FEA). The design procedure of stepped compound horn with LTV was provided. The vibration characteristics of actual horn were analyzed with simulation and test. The FEA results show that LTV of the output end of the stepped compound horn may be realized when the input end is excited by longitudinal vibration at certain natural frequency if suitable geometrical dimensions are selected, and the amplitude of the horn is periodical; the trajectory of the particle in the output end is helical curve. The test results indicate that LTV may be realized by stepped compound horn under single acoustic excitation, and the vibration frequency is close to the simulation result, and its vibration properties are good. This method may be applied to design the acoustics system of ultrasonic machining with LTV under single acoustic excitation.

The kinematics model was built based on the principle of ultrasonic deep rolling (UDR) with longitudinal-torsional vibration (LTV), and the trajectory equations of any particles on edge of the roller involved in the process were given; the influences of vibration parameters including phase angle, frequency of LTV, amplitude of longitudinal vibration, amplitude ratio and the rolling process parameters including roller radius, rolling depth, feed rate, the rotation frequency of roller on the trajectory, acoustic system design and processing quality were discussed. The results can provide theoretical basis for the design of acoustic system and optimization of process parameters.

Realization of longitudinal-torsional complex vibration by conical compound horn has more engineering application value with respect to the conventional longitudinal-torsional complex vibration converting devices. The frequency equations of longitudinal vibration and torsional vibration for the conical compound horn made up of cone and circular cylinder were given based on the wave theory of longitudinal vibration and torsional vibration of ultrasonic horn. The mechanism of the realization of longitudinal-torsional complex vibration by conical compound horn under single acoustic excitation was explained. And a numerical example indicated that longitudinal-torsional complex vibration could be realized by conical compound horn when the length and diameter of such horn were well chosen. The results of this study may be used in the field of longitudinal-torsional complex vibration ultrasonic machining.

In order to investigate the effect of titanium addition on the precipitating behavior of inclusions and corrosion resistance of niobium stabilized ferrite stainless steel, experiments were conducted in a high frequency vacuum induction furnace for smelting titanium and niobium stabilized ferrite stainless steel in argon atmosphere, and the composition, morphologies and size of inclusions in the samples were investigated. Precipitating behavior of the inclusions and intergranular corrosion resistance of the samples were analyzed by CSLM. Corrosion resistance of the steel in 2% NaHSO3 solution was tested by using electrochemistry comprehensive test instrument. The results show that inclusions in the as cast steel mainly are rectangle TiN, TiC, NbC and complex inclusions with TiN or TiC as core packed by NbC, and their size is about 1~5μm. There are a few nearly spherical complex inclusions with Al-Mg-Si-Ti-O as core packed by TiN, TiC, NbC or their complex inclusions. The spherical inclusions become rectangle with the increase of titanium addition, and the quantities of inclusions which size is larger than 5 μm increase. Precipitates increase during heat treated and grain size of the steel becomes a little smaller with the increase of titanium content in the steel. The grain boundary of the steel becomes stabilization and intergranular corrosion resistance enhances with the increase of titanium content in the steel according to the online analysis results. Passivation current density of the steel becomes smaller and passive potential range becomes wider in 2% NaHSO3 solution at 30°C with the increase of titanium content in the steel which indicates corrosion resistance of the steel being enhanced.

Simulations of the supersonic flow field inside and outside of the Laval nozzle with single hole and nine holes were carried out based on the computational fluid dynamics method. The effects of different standoff distance and particle diameter on impact velocity of Cu particle spraying from single hole and nine holes were investigated firstly. The results show that the particle velocity obtained with the nine holes nozzle is higher than that of the single hole nozzle under the same standoff distance, and the smaller the standoff distance, the higher the particle velocity may be obtained with the nine holes, and the higher particle velocity may be obtained with smaller particle diameter for particles with diameters of 1 ~ 15 μm. Furthermore the effects of different spraying pressure and temperature on particle velocity of Cu particle spraying from the nine holes nozzle were also studied. And the simulations indicate that the higher the spraying pressure and temperature may make the particle spraying with greater velocity.

A new-type of dredging equipment for the coal bunker is designed to solve the clogging problem, which avoids the disadvantages of the existing dredging technology used in the collieries. The new dredging method borrows ideas from air cannon dredging technology, and applies dynamic high pressure generation principle. In the process of dredging, the rubber bullet in the launch canister is accelerated by the controlled high pressure air, and impacts the coal in the arch with high speed so as to recover the coal bunker. The dredging mechanism and process are expatiated and the main structures of the dredging equipment are introduced. The structure of the new type dredging equipment for the coal bunker is simple and the equipment is of high adaptability and safety.

Research on ultrasonic extrusion under different process parameters for 45 steel shaft based on orthogonal test is carried out. The influences of various process parameters on shaft surface roughness and micro hardness are analyzed. The experimental results show that the influences of tool radius, pre-pressure, feed rate and rotating speed in the ultrasonic extrusion on surface roughness and micro hardness are different, but there are optimal values in the given experimental conditions. Compared with conventional extrusion, it can reduce the part surface roughness and improve surface micro hardness significantly in the process of ultrasonic extrusion.

Acoustic system is the core component of power ultrasonic, which is designed by traditional analytic method and modal analysis with finite element analysis method. And component of the step-like horn with rectangular sections and tool head used in two dimension ultrasonic polishing without abrasives are studied, and the calculating results and modal analysis results are consistent on the whole. The harmonic response analysis for the component of horn and tool head is carried out and the three dimensional coordinates of the vibrating node on the tool head with maximal displacement are obtained. The fitting result shows that the moving trajectory of such node is ellipses, which meets the experimental requirement well. So a new way for designing acoustic system of two dimensional ultrasonic vibration through combining theoretical calculation with computer aided design may be applied.

Two-dimensional ultrasonic vibration was introduced into common rolled extrusion, effect of the process parameters including tool head radius, feed speed, preload and spindle speed on the 45 steel shaft surface roughness were analyzed through orthogonal experiments. Experimental results show that lower value of surface roughness may be obtained in the process of two-dimensional ultrasonic rolled extrusion than that of common rolled extrusion, and the influence order of process parameters on surface roughness is feed speed, spindle speed, preload and tool head radius; the influence curves of tool head radius and spindle speed on surface roughness are concave curves, and influence curves of feed speed and preload on surface roughness are convex curves, or optimizing process parameters exist. The empirical formula for surface roughness is given using multiple regression analysis based on the experimental results. This study will provide a new technique for finishing precision parts.

Technology of NC-contour evolution ultrasonic assisted creep feed grinding (NC-CEUACFG) blade surface was put forward to solve the difficult problem of machining ceramic blade surface. The static load on the grinding wheel and the influence of the rigidity of the grinding wheel on the surface precision were studied combined with the movement analysis between the blade and grinding wheel in the process of NC-CEUACFG ceramic blade surface, and the physical model of static load may explain the decrease of grinding force and increase of the relative rigidity of the grinding wheel in NC-CEUACFG in theory. The primary experiment of NC-CEUACFG blade surface was carried out according to the experimental results of previous optimized process parameters, and the integral impeller was machined directly in the blank material of Al2O3 ceramic, which indicated the application prospect of such technology.

The gas velocity and particle velocity in and out of the nozzle have great influence on the coating effect in the process of cold spray. An axis-symmetric two-dimensional mathematical model was presented to study the flow field in and out of cold spray nozzle, and the effect of different pressure, temperature, spraying distance and particle diameter on gas axial velocity and particle velocity were researched. The simulation results showed that the gas axial velocity and particle velocity increased when the gas pressure and temperature were increased, spray distance had little effect on the flow field in the nozzle, and small diameter particle was more easily accelerated.

An ultrasonic grinding technology named NC-Contour Evolution Ultrasonic Assisted Creep Feed Grinding that using a simple shaped diamond grinding wheel with small diameter is presented to solve the machining problem of ceramic blade surfaces in integral impeller, which is similar to numerical control profile modeling milling. The grinding parameters of single grit in the grinding wheel are selected as the objective to make clear the grinding properties of creep feed grinding and ultrasonic grinding using grinding wheel with small diameter so as to explore the suitable processing parameters to machine ceramic blade surfaces in integral impeller in theory.

Experiments of ultrasonic polishing the 45# steel shaft without abrasive are carried out by using orthogonal test method to study the polished surface roughness, and experimental results are analyzed with range method. The influence of polishing parameters on the polished surface roughness could be arranged as follows: feed rate, power of generator, preload pressure and radius of the tool head, in which the feed rate brings the most remarkable influence on the polished surface roughness. The surface roughness value reduces at first and then increases when the radius of tool head, preload pressure and power of the generator increase. The surface roughness value increases with the feed rate. Comparative experimental results of ultrasonic polishing without abrasive and the conventional rolling indicate that lower surface roughness value may be obtained by ultrasonic polishing without abrasive.

In order to grind the ceramic blade surface with the Numerical Control contour evolution ultrasonic grinding method using the simple shape grinding wheel, primary comparative experiments of creep feed grinding with and without ultrasonic vibration were carried out to grind Al 2 O 3 ceramics so as to implore the effects of different process parameters on the machined surface quality. It can be concluded that when the direction of ultrasonic vibration is parallel to the direction of creep feed, the value of the surface roughness will be decreased; otherwise the surface quality will become worse. With the ultrasonic grinding method, the slower feed-rate, the smaller grinding depth, the higher grinding speed and the compound feed grinding method should be applied in order to improve the surface quality. The creep feed grinding mechanisms with and without ultrasonic vibration were analyzed theoretically from the experimental results. With the selected grinding parameters resulted from the experiments, the feasibility experiment of ultrasonic grinding ceramic blade surface was carried out.

The potential dechlorination of pentachlorophenol (PCP) in soil by a DCP-adapted consortium was investigated Results show that PCP dechlorination was enhanced under sulfate reduction and methanogenic conditions, but inhibited under denitrifying conditions within a 20-day incubation period. Under those same three conditions we also found that PCP dechlorination was enhanced by the addition of lactate, pyruvate, and acetate, but delayed by the addition of manganese oxide and inhibited by the addition of ferric chloride. In addition, our results failed to show any relationship between PCP dechlorination and oxidation-reduction potential (ORP) or changes in pH values. Treatment with lactate caused the greatest increase in methane production, the highest rates of sulfate or nitrate consumption; adding manganese oxide led to the second greatest increase, and the addition of ferric chloride the least. The addition of methylphenols and nitrophenols were found to inhibit PCP dechlorination. Methanogen may have constituted the major dechlorination population in our experimental consortium.

The potential of anaerobic degradation of three nitrophenols (NPs) including 2‐NP (2‐nitrophenol), 4‐NP (4‐nitrophenol), and 2,4‐DNP (2,4‐dinitrophenol) by river sediment was investigated. Observed degradation rates occurred in the order of 2,4‐DNP > 2‐NP > 4‐NP. Optimal temperature and pH values for NP degradation were 40°C and 8.0 to 9.0, respectively. We also found that 2‐NP degradation was delayed by the addition of 4‐NP and 2,4‐NP, but enhanced by the addition of pyruvate, acetate, or lactate. Following treatment with bromoethanesulfonic acid (BESA) and vancomycin, we found that eubacteria was the major microbial population involved in the degradation of NPs.

Ultrasonic machining is a practical process for advanced ceramic machining. Usually, ceramics with complex surfaces are machined with two common ultrasonic assisted contour machining methods, which may be classified as surface/point contact machining mode. While these methods are not suitable to machine some complex surfaces such as blade surface, so an ultrasonic assisted contour machining method using a simple shaped diamond grinding wheel to machine ceramic blade surface is presented, which is named as Numerical Control-Contour Evolution Ultrasonic Assisted Grinding (NC-CEUAG) method. In the NC-CEUAG process, the contour evolution motion of the grinding wheel is controlled by the NC system and the blade surface is the enveloping surface formed by the grinding wheel’ cutting edges when they cut into the ceramic specimen. In this paper, the relative motion between the grinding wheel and the specimen in the process of NC-CEUAG ceramic blade surface is analyzed. The mathematical models of ruled surfaces are constructed. The ceramic blades with ruled surface are machined with selected machining parameters on the retrofitting NC-CEUAG machine tool.