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As a commonly used physical intervention, electrical stimulation (ES) has been demonstrated to be effective in the treatment of central nervous system disorders. Currently, researchers are studying the effects of electrical stimulation on individual neurons and neural networks, which are dependent on factors such as stimulation intensity, duration, location, and neuronal properties. However, the exact mechanism of action of electrical stimulation remains unclear. In some cases, repeated or prolonged electrical stimulation can lead to changes in the morphology or function of the neuron. In this study, immunofluorescence staining and Sholl analysis are used to assess changes in the neurite number and axon length to determine the optimal pattern and stimulation parameters of ES for neurons. Neuronal death and plasticity are detected by TUNEL staining and microelectrode array assays, respectively. mRNA sequencing and bioinformatics analysis are applied to predict the key targets of the action of ES on neurons, and the identified targets are validated by western blot analysis and qRT-PCR. The effects of alternating current stimulation (ACS) on neurons are more significant than those of direct current stimulation (DCS), and the optimal parameters are 3 μA and 20 min. ACS stimulation significantly increases the number of neurites, the length of axons and the spontaneous electrical activity of neurons, significantly elevates the expression of growth-associated protein-43 (GAP-43) without significant changes in the expression of neurotrophic factors. Furthermore, application of PI3K/AKT-specific inhibitors significantly abolishes the beneficial effects of ACS on neurons, confirming that the PI3K/AKT pathway is an important potential signaling pathway in the action of ACS.

With the rapid development of artificial intelligence technology, data-driven advanced models have provided new ideas and means for airfoil aerodynamic optimization. As the advanced models update and iterate, many useful explorations and attempts have been made by researchers on the integrated application of artificial intelligence and airfoil aerodynamic optimization. In this paper, many critical aerodynamic optimization steps where data-driven advanced models are employed are reviewed. These steps include geometric parameterization, aerodynamic solving and performance evaluation, and model optimization. In this way, the improvements in the airfoil aerodynamic optimization area led by data-driven advanced models are introduced. These improvements involve more accurate global description of airfoil, faster prediction of aerodynamic performance, and more intelligent optimization modeling. Finally, the challenges and prospect of applying data-driven advanced models to aerodynamic optimization are discussed. [ABSTRACT FROM AUTHOR]

In this research, we introduce a deep-learning-based framework designed for the prediction of transonic flow through a linear cascade utilizing large-scale point-cloud data. In our experimental cases, the predictions demonstrate a nearly four-fold speed improvement compared to traditional CFD calculations while maintaining a commendable level of accuracy. Taking advantage of a multilayer graph structure, the framework can extract both global and local information from the cascade flow field simultaneously and present prediction over unstructured data. In line with the results obtained from the test datasets, we conducted an in-depth analysis of the geometric attributes of the cascades reconstructed using our framework, considering adjustments made to the geometric information of the point cloud. We fine-tuned the input using 1603 data points and quantified the contribution of each point. The outcomes reveal that variations in the suction side of the cascade have a significantly more substantial influence on the field results compared to the pressure side and explain the way graph neural networks work for cascade flow-field prediction, enhancing the comprehension of graph-based flow-field prediction among developers and proves the potential of graph neural networks in flow-field prediction on large-scale point clouds and design. [ABSTRACT FROM AUTHOR]

Electrorheological (ER) fluid, as an intelligent material, is a kind of suspension composed of polarized micro‐ and/or nanoparticles dispersed into insulating oil. In recent years, molybdenum disulfide (MoS2), as the hottest 2D material, has provided a new strategy to develop the high‐performance ER materials. 2D‐based ER composites can provide large surface to enhance the polarization. But the MoS2 ER material has many disadvantages such as low polarization strength and high electrical conductivity. To make up these defects, polyaniline (PANI) is used to combine with lamellar MoS2. Herein, PANI and MoS2 hybrid composite nanoparticles with special morphology are prepared by two‐step method. The coating material has special morphology, high interfacial polarization, specific surface area, and low density. The optimum reaction ratio is obtained by adjusting the proportion of MoS2 and PANI. When the proportion of PANI and MoS2 is 4:1, the material performance is best, in which the shear stresses can reach 150 Pa. In a word, it is proved that the material is an excellent electrorheological material. [ABSTRACT FROM AUTHOR]

As a core component of an aero-engine, the aerodynamic performance of the nacelle is essential for the overall performance of an aircraft. However, the direct design of a three-dimensional (3D) nacelle is limited by the complex design space consisting of different cross-section profiles and irregular circumferential curves. The deep manifold learning-assisted geometric multiple dimensionality reduction method combines autoencoders (AE) with strong capabilities for non-linear data dimensionality reduction and class function/shape function transformation (CST). A novel geometric dimensionality reduction method is developed to address the typical constraints of nacelle parameterization. Low-dimensional latent variables are extracted from the high-dimensional design space to achieve a parametric representation of 3D nacelle manifolds. Compared with traditional parametric methods, the proposed geometric dimensionality reduction method improves the accuracy and efficiency of geometric reconstruction and aerodynamic evaluation. A multi-objective optimization framework is proposed based on deep manifold learning to increase the efficiency of 3D nacelle design. The Pareto front curves under drag divergence constraints reveal the correlation between the geometry distribution and the surface isentropic Mach number distribution of 3D nacelles. This paper demonstrates the feasibility of the proposed geometric dimensionality reduction method for direct multi-objective optimization of 3D nacelles. [ABSTRACT FROM AUTHOR]

In this paper, the effects of citric acid (CA) and protein retarder (SC) on the properties of phosphogypsumsulfoaluminate cement composite cementitious system were investigated. The fluidity, setting time and compressive strength were tested to evaluate the workability and mechanical of composite system, and the change of conductivity, phase composition and microstructure were analyzed to clarify the influence mechanism of different retarders. The results show that the strength loss of composite cementitious system under the action of SC is smaller than that of CA when the same setting time is achieved. The addition of two retarders has a certain inhibitory effect on the dissolution of composite system during the hydration induction and the acceleration period, and CA has a greater inhibitory effect than SC at the same content. CA can cause gypsum dihydrate crystals to show a flat and coarse structure, which has a greater impact on the mechanical properties, while SC increases the overall scale of gypsum dihydrate crystals, with little change in crystal morphology, which has a smaller effect on the deterioration of the mechanical properties of composite system. [ABSTRACT FROM AUTHOR]

Conventional approaches of design variable generation in nacelle design cases are usually proposed from either of two perspectives: (1) utilizing geometric resemblance to airfoil shape; or (2) selecting flexible geometric parametrization so that any potential geometry can be produced. However, the relationship between geometry and aerodynamic performance objectives is not emphasized in these approaches: design variables are likely not carrying the information that is most needed for aerodynamic optimization, as is the case in nacelle cowl design of drag reduction. In fact, an ideal aerodynamic information should be related with the move of samples toward better aerodynamic performance in design space. As an attempt to fix this issue, this paper proposes a new design variable generation method by extracting objective space (i.e., the aerodynamic performance of samples mapped from nacelle design space) information via linear discriminant analysis (LDA). By accomplishing this "objective space filtration," the aerodynamic performance improvement potential is injected into design variable generation. Proof-of-concept studies of nacelle cowl design are provided in the paper demonstrating a more direct relationship that links: (1) LDA-aided design variables versus cowl drag, and (2) LDA-aided design variables versus shock strength and laminar length, respectively. LDA is used in the studies as a classic technique of classification, so that the analysis of objective space information finds a way to have impact on design space. The new approach outperforms a controlled test realized by Proper Orthogonal Decomposition in terms of reflecting aerodynamic information in design space, in that a localized improvement of aerodynamic objectives can be more clearly seen in the newly generated design variables. The result shows that the new design variable generation helps improve aerodynamic design and that it can be further extended to other cases beyond the scope of nacelle cowl design. [ABSTRACT FROM AUTHOR]

In this paper, a new aerodynamic solution strategy for non-smooth configurations is proposed based on the wall modification model by machine learning to perform numerical simulations, rather than directly describing the global flow field with massive grids. The aerodynamic effect of non-smooth configurations in the presence of pressure gradients is investigated utilizing the proposed method. Flow features of non-smooth surface are provided by high-fidelity surface flow data acquired through lattice Boltzmann method simulation. The wall modification model is constructed by Fruit fly Optimization Algorithm-Generalized Regression Neural Network (FOA-GRNN) to reproduce the behavior of microflow near the non-smooth surface. Typical flow features, e.g., velocity corrections induced by surface texture as the output of the FOA-GRNN model, are imposed on configuration boundaries, improving computational efficiency and wall resolution. The novel aerodynamic solution strategy is validated by comparing the results of the experiment. In addition, the performance analysis of compressor cascade with micro riblet surface utilizing the above method is conducted. The results indicate that the non-smooth surface structure decreases skin friction and turbulent intensity in the flow channel compared with smooth cascade, thus significantly reducing the total pressure loss. The paper shows a positive prospect of the data-driven strategy in evaluating the aerodynamic performances of non-smooth configurations and provides a reliable solution method for the subsequent design of micro-nano surfaces. [ABSTRACT FROM AUTHOR]

Due to the harsh operating environment of aero-engines, a surface structure that provides excellent aerodynamic performance is urgently required to save energy and reduce emissions. In this study, microgroove polyurethane coatings fabricated by chemical synthesis are investigated in terms of their effect on aerodynamic performance, which is a new attempt to investigate the impact on aerodynamic performance of compressor cascade at transonic speeds. This method reduces manufacturing and maintenance cost significantly compared with traditional laser machining. Wake measurements are conducted in the high-speed linear compressor cascade wind tunnel to evaluate the performance of cascade attached with different microgroove polyurethane coatings. Compared with the Blank case, the microgroove polyurethane coatings have the characteristic of reducing flow loss, with a maximum reducing rate of 5.87% in the area-averaged total pressure loss coefficient. The mechanism of flow loss control is discussed through analyzing the correlation between the total pressure distribution and turbulence intensity distribution. The results indicate that a large quantity of energy loss in the flow field due to turbulence dissipation and the reduction in viscous drag by microgroove polyurethane coatings relates to its effect on turbulence control. This paper demonstrates a great perspective on designing micro-nano surface structure for aero-engine applications. [ABSTRACT FROM AUTHOR]

Peripheral nerve injuries represent one of the most common causes of permanent disabilities. Therapeutic electrical stimulation has been widely used in neural regeneration for decades. Combined with the implantation of a nerve cuff, several outcomes have proven effectiveness and feasibility in neuroprosthetic applications. However, the current electrical stimulation strategy fails to complete nerve repair. There is a lack of research on long‐term implantable nanogenerators in the neurostimulation scenario. Especially considering many disease models, those devices may not reach the in vitro simulative working setting. Thus, an implanted sciatic nerve stimulation system that spontaneously generates biphasic electric pulses in response to rats' movement is developed. The electric signals generated by this device could stimulate injured sciatic nerve by cuff electrode. This work introduces an implantable self‐regulated neural electrical stimulation system generated by a contact separation triboelectric nanogenerator with a nerve cuff electrode and compares it with chronic therapeutic electrical stimulation for sciatic nerve restoration effect. Neural function restoration is observed in gait and histological analysis. Moreover, the upregulation of growth associated protein 43 can be a protentional target. This could have potential clinical application in facilitating closed‐loop energy harvesting for long‐term electrical stimulation. [ABSTRACT FROM AUTHOR]

The multi-objective optimization of compressor cascade rotor blade is important for aero engine design. Many conventional approaches are thus proposed; however, they lack a methodology for utilizing existing design data/experiences to guide actual design. Therefore, the conventional methods require and consume large computational resources due to their need for large numbers of stochastic cases for determining optimization direction in the design space of problem. This paper proposed a Reinforcement Learning method as a new approach for compressor blade multi-objective optimization. By using Deep Deterministic Policy Gradient (DDPG), the approach modifies the blade profile as an intelligent designer according to the design policy: it learns the design experience of cascade blade as accumulated knowledge from interaction with the computation-based environment; the design policy can thus be updated. The accumulated computational data is therefore transformed into design experience and policies, which are directly applied to the cascade optimization, and the good-performance profiles can be thus approached. In a case study provided in this paper, the proposed approach is applied on a blade profile, which is thus optimized in terms of total pressure loss and laminar flow area. Compared with the initial profile, the total pressure loss coefficient is reduced by 3.59 % , and the relative laminar flow area at the suction surface is improved by 25.4 % . [ABSTRACT FROM AUTHOR]

The treatment methods of asphalt pavement diseases, and the preparation and testing methods of modified asphalt crack paste specimens are introduced. The impact of plasticiser, modifier, tackifier and padding on softening point, low temperature flexibility, peel strength, shear strength and continuous cohesiveness of asphalt/crack paste are discussed respectively, and the results showed that, the addition of plasticizer could improve the performance of asphalt/crack paste. Then a suitable material ratio was obtained in combination of environmental protection and the cost, and the performance of the crack paste prepared according to this ratio were tested. [ABSTRACT FROM AUTHOR]

QiShenYiQi dripping pills (QSYQ), a traditional Chinese medicine, are commonly used to treat coronary heart disease, and QSYQ was recently approved as a complementary treatment for ischemic heart failure in China. However, only few studies reported on whether QSYQ exerts a protective effect on heart failure induced by pressure overload. In this study, we explored the role of QSYQ in a mouse model of heart failure induced by transverse aortic constriction (TAC). Twenty-eight C57BL/6J mice were divided into four groups: Sham + NS group, Sham + QSYQ group, TAC + NS group, and TAC + QSYQ group. QSYQ dissolved in normal saline (NS) was administered intragastrically (3.5mg/100 g/day) in the Sham + QSYQ and TAC + QSYQ groups. In the Sham + NS and TAC+NS groups, NS was provided every day intragastrically. Eight weeks after TAC, echocardiography, and cardiac catheterization were performed to evaluate the cardiac function, and immunofluorescent staining with anti-actinin2 antibody was performed to determine the structure of the myocardial fibers. Moreover, TUNEL staining and Masson trichrome staining were employed to assess the effects of QSYQ on cardiac apoptosis and cardiac fibrosis. Western blots and real-time polymerase chain reaction (PCR) were used to measure the expression levels of vascular endothelial growth factor (VEGF) in the heart, and immunohistochemical staining with anti-CD31 antibody was performed to explore the role of QSYQ in cardiac angiogenesis. Results showed that TAC-induced cardiac dysfunction and disrupted structure of myocardial fibers significantly improved after QSYQ treatment. Moreover, QSYQ treatment also significantly improved cardiac apoptosis and cardiac fibrosis in TAC-induced heart failure, which was accompanied by an increase in VEGF expression levels and maintenance of microvessel density in the heart. In conclusion, QSYQ exerts a protective effect on TAC-induced heart failure, which could be attributed to enhanced cardiac angiogenesis, which is closely related to QSYQ. Thus, QSYQ may be a promising traditional Chinese medicine for the treatment of heart failure induced by pressure overload such as hypertension. [ABSTRACT FROM AUTHOR]

Our previous work showed that a plasmid-based chicken interleukin-7 (chIL-7) gene expression vector possessed potent adjuvant activity for a VP2 DNA vaccine against chicken infectious bursal disease virus (IBDV). Whether recombinant chIL-7 prepared in procaryotic expression system has the adjuvant activity for inactivated IBDV vaccine remains unknown. Here, we prepared recombinant chIL-7 using an E. coli expression system and analyzed its adjuvant activity for the inactivated IBDV vaccine. The results show that the recombinant chIL-7 was successfully prepared in E. coli using the pET20b vector, which possessed biological activity to stimulate mouse B lymphocyte proliferation. Co-administration of the chIL-7 with inactivated IBDV vaccine significantly increased specific serum antibody titers against IBDV, enhanced lymphocyte proliferation and IFN-Υ and IL-4 productions and increased protection against virulent IBDV infection. [ABSTRACT FROM AUTHOR]

We analyzed the effects of matrix metalloproteinase (MMP)-1, MMP-3, and MMP-12 on the degree of carotid atherosclerosis (CAS) and plaque stability, and investigated their correlations with cardiovascular and cerebrovascular events (CCEs). Two hundred CAS patients were enrolled. Carotid intima-media thickness (IMT) was measured using ultrasonic examination. Patients were divided into the no plaque group (NP group), stable plaque group (SP group), and vulnerable plaque group (VP group). The Crouse method was used for the evaluation of plaque scores. Additionally, 60 healthy subjects were enrolled as the control group. Serum triacylglycerol (TG), total cholesterol (TC), low density lipoprotein cholesterol (LDL-C), and high density lipoprotein cholesterol (HDL-C) were analyzed. The serum protein levels of MMP-1, MMP-3, and MMP-12 were measured by western blotting. The frequency of CCEs within 2 years was recorded, and its correlation with MMP-1, MMP-3, and MMP-12 was analyzed. The CAS plaque scores in the SP and VP groups were significantly increased compared with the NP group, and the difference between the SP and VP groups was significant. The levels of TC, TG, LDL-C, and HDL-C of CAS patients were significantly increased compared with those in the control group, but the differences in these indexes between the patient groups were not significant. Western blotting showed that the levels of MMP-1, MMP-3, and MMP-12 in the patient groups were significantly increased compared with those in the control group, and the protein levels in the VP group were significantly higher than those in the SP and NP groups. Additionally, the levels of MMP-1, MMP-3, and MMP-12 had significantly positive correlations with the occurrence of CCEs in CAS patients. In conclusion, MMP-1, MMP-3, and MMP-12 are positively correlated with CCEs in CAS patients. They can be used as markers for the clinical diagnosis and prognosis of CAS. [ABSTRACT FROM AUTHOR]

The relationship between the government and market is, in nature, the issue of two kinds of orders. Under the impact of economic globalization and financial crisis, the fundamental issue of the reorganization and economic transformation of domestic steel enterprises is that of in-time transformation of governmental governance model and role. The essential pathway of the reorganization of steel enterprises and transformation of economic structure is achieved through the transformation of governmental governance in the following aspects: changing the model of governmental governance from administrative intervention in economic operation to limited, accountable and rule-of-law modern governance, establishing fair and just rules, improving systems of property rights, modern enterprise and the accountability of government investment projects, continuing to exert macroeconomic control and to press the government to quit fields of ordinary market competition, overcoming administrative monopoly and regional protectionism and advancing the standardization and perfection of the market order. [ABSTRACT FROM AUTHOR]

Human CD83 is type I transmembrane glycoprotein, mainly expressed on mature dendritic cells (DCs), so it was first described as a molecular marker for mature DC. However, increasing evidence has demonstrated that CD83 is also an immunomodulatory molecule either its membrane-bound CD83 (mCD83) or soluble CD83 (sCD83) released from DCs. Intriguingly, the mCD83 possesses stimulatory effects on immune response, on the contrary, the sCD83 has inhibitory effects. Whether the sCD83 has the inhibitory effects on human monocyte differentiation into DCs is unknown. To this end, we prepared the recombinant human sCD83 in HEK293T cells and treated human monocytes being differentiated into DCs in vitro with the sCD83, and evaluate sCD83 inhibitory effects on immune response by analyzing the surface marker pattern of the cells. The results showed that the sCD83, especially glycosylated sCD83 could bind the monocytes and significantly inhibited the depression of CD14 expressions ( P < 0.01) and reduced CD1a, CD80, CD86 and MHC II expressions ( P < 0.01 or P < 0.05) during the differentiation, indicating that the sCD83 can inhibit monocyte differentiation into DCs, and suggesting that a negative feedback regulation may exist in monocyte differentiation into DCs based on sCD83 released from the mature DCs. [ABSTRACT FROM AUTHOR]

Abstract: Porcine reproductive and respiratory syndrome virus (PRRSV) infection results in extensive tissue inflammation and damage, which are believed to be responsible for increased susceptibility to secondary infection and even for death. However, its pathogenic mechanisms are not fully understood. To explore the mechanism underlying the PRRSV-induced tissue inflammation and damage, we investigated whether PRRSV activates porcine alveolar macrophage (PAM) inflammasomes which mediate por-IL-1β maturation/release and subsequently induce tissue inflammation and injury. Our results showed that PRRSV and its small envelope protein E significantly increased IL-1β release from LPS-primed PAMs; however, only PRRSV not protein E significantly increased IL-1β release from no-LPS-primed PAMs, which indicates PRRSV can activate inflammasomes of PAMs by its encoded protein E. These results provide a molecular basis for the pathogenic mechanism of PRRSV on inducing extensive tissue inflammation and damage, and suggest that the inflammasome may provide a potential therapeutic target for PRRS prevention and treatment. [Copyright &y& Elsevier]

In this work, a kind of ternary hybrid material, MIL-125/MoS 2 /SiO 2 , was prepared by a solvothermal and Stöber method. In this system, MIL-125, as the matrix material, not only furnishes a large specific surface area for MIL-125/MoS 2 /SiO 2 , thereby providing a basis for stronger interfacial polarization, but also effectively enhances the antisettlement ability of the electrorheological fluids (ERFs). Different characterizations, such as scanning electron microscopy, transmission electron microscopy, XRD, XPS, FT-IR, BET, electron mapping, etc., were used to analyze the ternary nanohybrid. The ERFs prepared by combining the different advantages of the three materials in the hybrid system were studied by a HAAKE high-speed rotary rheometer. In addition, the combination of MoS 2 and SiO 2 provides suitable electrical conductivity and dielectric properties for the system to promote the generation of interface polarization, ensuring that the entire system exhibits stronger electrorheological behavior without electrical breakdown and thus obtains higher shear stress.