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Extracellular vesicles (EVs) derived from living cells play important roles in donor cell-induced recipient tissue regeneration. Although numerous studies have found that cells undergo apoptosis after implantation in an ischemic-hypoxic environment, the roles played by the EVs released by apoptotic cells are largely unknown. In this study, we obtained apoptotic vesicles (apoVs) derived from human deciduous pulp stem cells and explored their effects on the dental pulp regeneration process. Our work showed that apoVs were ingested by endothelial cells (ECs) and elevated the expression of angiogenesis-related genes, leading to pulp revascularization and tissue regeneration. Furthermore, we found that, at the molecular level, apoV-carried mitochondrial Tu translation elongation factor was transported and regulated the angiogenic activation of ECs via the transcription factor EB-autophagy pathway. In a beagle model of dental pulp regeneration in situ, apoVs recruited endogenous ECs and facilitated the formation of dental-pulp-like tissue rich in blood vessels. These findings revealed the significance of apoptosis in tissue regeneration and demonstrated the potential of using apoVs to promote angiogenesis in clinical applications.

The dynamic magnetic properties of the nonequilibrium Fe4N system are calculated on the basis of correlated effective-field theory (EFT). The dynamic phase diagrams are plotted for different values of the oscillating magnetic field and the crystal field. The reentrant behavior, the dynamic tricritical point and the dynamic critical end point observed in certain case by using EFT are established to emerge as the generic nonequilibrium features of the Fe4N system. Moreover, we compare our results with those produced by mean-field theory (MFT), and find that the first-order phase transition and the reentrant phenomena are significantly reduced due to the consideration of spin–spin thermal fluctuations in EFT approximations. Our findings lead us to conclude that the thermal fluctuations considered in EFT are a critical factor for the dynamic magnetic properties of the nonequilibrium Fe4N system.

Peisheng Liu,1,* Xiaofeng Li,1,* Jing Liu,2 Hengjia Zhang,1 Zhitao You,1 Jianfeng Zhang1 1Department of Spinal Surgery, Yantaishan Hospital, Yantai, People’s Republic of China; 2Basic Department, Yantai Vocational College, Yantai, People’s Republic of China*These authors contributed equally to this workCorrespondence: Jianfeng Zhang, Department of Spinal Surgery, Yantaishan Hospital, No. 10087, Keji Avenue, Laishan District, Yantai, People’s Republic of China, Tel +86-13780921732, Email zhangjfdoctor@126.comBackground: Cervical spondylotic myelopathy (CSM) is a spinal cord disease caused by cervical disc degeneration and related pathological changes. Cervical spondylotic myelopathy may result from inflammation responses and neuronal damage. Thioredoxin-interacting protein (TXNIP)/NOD-like receptor protein 3 (NLRP3) signaling promotes inflammation. However, the effects of TXNIP/NLRP3 on the pathogenesis of CSM have not been reported.Methods: A rat model of chronic cervical cord compression was established to observe changes in the levels of of TNXIP/NeuN and NLRP3/NeuN expression in the damaged anterior horn of the spinal cord following progression of CSM. Rats were injected with TXNIP small interfering RNA (siRNA) and scrambled control to determine the effects of TXNIP inhibition on NLRP3-mediated inflammation in rats with CSM. Behaviors effects and the expression of NLRP3 and pro-caspase-1 in the damaged spinal cord were evaluated.Results: The expression levels of TXNIP and NLRP3 were significantly increased in the damaged anterior horn of the spinal cord following CSM. Injection of TXNIP siRNA significantly improved behavioral measures and decreased apoptosis in the damaged anterior horn of spinal cord. Furthermore, the levels of NLRP3 and pro-caspase-1 in the lesioned area were reduced by the TXNIP siRNA injection.Conclusion: Thioredoxin-interacting protein participated in NLRP3 mediated inflammation in a rat model of CSM, which indicated that TXNIP may be a potential therapeutic target in improving CSM.Keywords: neuroinflammation, TXNIP/NLRP3, spinal cord dysfunction, pro-caspase-1

Purpose With the nickel foam made by the technique of electrodeposition on polymer foam, the purpose of this paper is to investigate the influence of several deferent processes on the surface morphology and the specific surface area of this porous product. Design/methodology/approach The surface morphologies of the nickel foam were examined by SEM. The specific surface area of the porous product was measured by gas (N2) permeability method and also calculated by the reported formula. Findings The nickel foam from sintering in NH3 decomposition atmosphere at 850°C will achieve the same specific surface area as that at 980°C, whether this porous structure after electrodeposition comes through direct sintering in NH3 decomposition atmosphere, or through burning in air at 600°C for 4 min beforehand then the same reductive sintering. Originality/value There have been some studies on the preparation and application of nickel foam, but few works focus on the processing influence on the specific surface of this porous product. The present work provides the investigations on the difference of the product made under different producing conditions, and the influence of several deferent processes on the specific surface area of the product.

With the development of manufacturing and society, a large amount of end-of-life products are generated but with reuse value. Therefore, it is of great significance to dismantle and reuse them. A robotic linear disassembly line plays an important role and promotes the disassembly efficiency in a disassembly process. In this work, we establish a mathematical model of a linear robotic disassembly line balancing problem, which requires the maximization of profit and minimization of energy consumption. Then, an improved ant lion optimizer is proposed to optimize the objectives of the multi-objective robotic disassembly line balancing problem. The experimental results show that the multi-objective ant lion optimizer has good performance, and the diversity and convergence are better than its peers.

In disassembly industry, the disassembly efficiency closely depends on a reasonable disassembly mode and an efficient disassembly line. In the current manufacturing, the profit of multi-product partial U-shaped disassembly-line-balancing (MPUD) is relatively low and the energy consumption is high. According to the characteristics of the MPUD problem, a mathematical model for maximizing profit and minimizing energy consumption of human-robot disassembly is established. To solve the MPUD problem, a multi-objective strength Pareto evolutionary algorithm II is developed and crossover and mutation operators are improved to promote the convergence and feasibility of the algorithm. We perform the experiments on a ballpoint pen and a washing machine to simulate the disassembly process and compare the proposed algorithm with the nondominated sorting genetic algorithm II and the multi-objective evolutionary algorithm based on decomposition. Experimental results show that the proposed algorithm has obvious advantages in the most important metrics.

CoNiGa ternary alloy nanowire arrays were successfully fabricated by simple DC electrodeposition into the anodized aluminum oxide (AAO) templates. A systematic study of the potential and components of the electrolyte were conducted to obtain different components of CoNiGa nanowires. The largest Ga content in the prepared alloy nanowires was about 17%, while for Co and Ni contents which can be controlled in a wide range by adjusting the composition and pH value of the electrolyte appropriately. X-ray diffraction analysis confirmed that the as-grown CoNiGa nanowire arrays were polycrystal with fcc phase of Co where Co atoms partially substituted by Ni and Ga. Magnetization curves of samples with different composition were measured at room temperature as well as low temperature. The results showed that the components of the alloy nanowires have a great impact on its magnetic properties. For Co55Ni28Ga17 nanowires, the magnetization reversal mode changes from curling mode to coherent rotation as the angle increases, and the temperature dependence of coercivity can be well described by the thermal activation effect.

With the continuous development of society, the increasing number and size of oil-gas pipelines, how to ensure the safe operation of the pipeline has become a major problem. At the same time, under the premise of defects, it is of great significance to predict the residual strength of pipeline for the safety of pipeline operation. At present, scholars at home and abroad have conducted in-depth studies on the evaluation of residual strength of pipelines, but there are mainly two problems in the research, namely, low evaluation accuracy and inconvenient application of evaluation method. Therefore, based on SVM algorithm, a residual strength prediction model for single-defect pipelines is established from four aspects, including model construction, parameter optimization, node number determination of hidden layers and kernel function optimization. The prediction results are highly feasible and advanced compared with various algorithms and standard methods.

The defect identification and evaluation of buried steel pipeline is a long-term challenge in the field of pipeline detection, and the prerequisite for efficient identification of defects is the accurate extraction of pipeline damage signals. Aiming at the characteristics of buried pipeline defect signals, a method of pipeline defect signal extraction and recognition is proposed, which is based on support vector machine (SVM). A dictionary is obtained by learning from the original signal, the dictionary is used to construct a sparse model of the defect signal using a regularized orthogonal matching pursuit algorithm, and the feature vector of the signal is obtained according to the compressed sensing theory. Furthermore, multi-classification SVM is used to establish a mapping relationship between the feature vector of the defect signal and the actual defect type of the pipeline, and Genetic Algorithm-Particle Swarm Optimization is used to guide the selection of SVM parameters. The results showed that the proposed classification method can realize the accurate division of the damage degree of pipeline defects.

Purpose The purpose of this paper is to investigate the sound absorption by modeling for the aluminum foam produced by press infiltration casting. Design/methodology/approach First use Johnson-Allard-Champoux (JAC) model to calculate the sound absorption coefficient of the present aluminum foam, and then improve it after finding its deviation from the experimental data, so as to get an improved model that could have a good agreement with the experimental result. Findings Using JAC model to calculate the sound absorption coefficient of the present aluminum foam, it is found that the model may have a good agreement with the experimental data only for the sound wave frequency below the absorption peak frequency, but a large deviation from the experimental result for the sound wave frequency above this frequency. Originality/value Improving JAC model by means of two factors, i.e., the absorption peak frequency and the specific surface area, the resultant improved model could be in good agreement with the experimental data.

We realized the desired spheroidizing of NiCo2O4 nanomaterials by laser irradiating NiCo2O4 suspensions with different concentrations. The results reveal that the as-prepared samples are desired spheres with the maximal average size of 568 nm and the superior dispersity, which were obtained at the energy density of 0.30 J·pulse-1·cm-2 and NiCo2O4 suspension concentration of 0.2 mg·mL-1. However, the phase segregation, which was induced by large amounts of solid redox of Co3+/Co2+ and Ni3+/Ni2+, also appears in the laser-irradiation process.

Electrochemical reaction induced by gate voltage between metallic cobalt and cobalt oxides was found to remarkably reshape average volume of superparamagnetic particles in Pt/Co/AlOx stacks at room temperature and thus modulate superparamagnetic properties, such as saturation fields and saturated magnetization, of the superparamagnetic films. The interfacial reaction was indicated in anomalous Hall transport measurement. This voltage-controllable superparamagnetism observed in Pt/Co/AlOx films could be utilized in a new architecture of nonvolatile and high density magnetic random access memories or neuromorphic computing.

Different SrS:0.03Eu 2+ , 0.03Dy 3+ nanostructures (including nanoflower, nano hollow sphere and rod-like porous nanostructure) were successfully synthesized by a microemulsion method together with post-annealing process. The photoluminescence and afterglow properties of these nanostructures were investigated. The evolution of morphology and the relation between morphology and the afterglow property were discussed. The results indicated that the material instable in solution could also be synthesized in nanoscale by microemulsion method together with post annealing.

Expanding localized surface plasmon resonance (LSPR) towards long wavelengths has been the focus of plasmonics for several decades. Compared with the most studied Au and Ag nanoparticles, Cu nanoparticles have intrinsic long-wavelength LSPR, but hard to be facially fabricated due to their sensitivity to oxidation. Here, we report on the facile and rapid fabrication of colloidal copper nanoparticles by laser ablation in liquid (LAL) operated in ambient conditions, and their LSPR properties. A formation mechanism was put forward to reveal the optical properties of colloidal copper nanoparticles. The effects of different parameters, such as laser power density, ablation time, surfactant concentration, organic solvents and aging time, on LSPR properties were investigated. Eventually, we can decrease the oxidation of colloidal copper nanoparticles by mediating disparate factors, and then tune the position and intensity of copper LSPR peaks. And our results will be beneficial to the application of copper LSPR in optical catalysis, sensitivity, detection devices, and conductive pattern making based on the printing technologies.

Several nanotechnology applications are based on the promising scheme of highly anisotropic magnetic nanomaterials. Using this idea, we investigated the structure, magnetic properties, and interfacial exchange anisotropy effects of the Ni/Cr2O3 and Fe/Cr2O3 core–shell nanowires (NWs) geometry. A template-based strategy was developed to synthesize Ni (Fe)–Cr2O3 core–shell NWs, which combines a wet-chemical route and electrodeposition within the nanopores of the membranes. Structural determination in correlation with magnetic testing shows that the crystalline Cr2O3-nanoshells (NSs) cause an enhanced exchange bias, providing an extra source of anisotropy that leads to their magnetic stability. This core–shell NWs geometry, with enhanced anisotropy, should, therefore, motivate further study related to the applicability of anisotropic nanostructures. Our design opens a new pathway to obtain optimized heterostructured nanomaterials exhibiting tunable magnetic properties.

The effective-field theory is used to study the anomalous metamagnetic behavior of a uniaxial ferromagnetic film, which has been observed in the recent experiment Riego et al. (2017). Similar to experimental findings, the sidebands phenomena of the dynamic susceptibility have been shown in certain ranges of the bias field, as well as the amplitude and period of the oscillating magnetic field. The mechanism and precise nature of the anomalous metamagnetic behavior have been explored in detail as well. We also compare the effective-field theory results to those produced using mean-field theory and Monte Carlo simulations. We find that the analytic treatment of the effective-field theory is in good qualitative agreement with exact results of the Monte Carlo simulations.

A versatile approach towards nanofabrication of highly reproducible Co/BiCoO3 (Co/BCO) core/shell (CS) nanowires (NWs) with different diameters has been adopted by demonstrating easily available and low cost sol–gel and electrodeposition routes. X-ray diffraction (XRD) analysis confirmed the tetragonal system of the BCO nanoshells (NSs) with the space group P4mm. Scanning electron microscopy (SEM) clearly demonstrates the uniform morphology with well aligned CS NWs. The magnetization reversal processes (MRPs), experimentally and with analytical modelling, have been discussed for CS NWs with θ ranging from 0° (in-plane magnetic easy axis) to 90° (out-of-plane magnetic hard axis) with magnetic hysteresis loops and geometrical parameters. Crossover from the vortex to transverse reversal mode on increasing θ has been observed for all diameters. An exchange bias effect has been observed for smaller CS NWs diameters and it is attributed to the shell thickness of ∼25 nm. Furthermore, the magnetic anisotropy effect has been discussed in some detail.

Applications of ZnMgO nanocrystals (NCs), especially in photoelectric detectors, have significant limitations because of the unresolved phase separation in the synthesis process. Here, we propose a rapid and highly efficient ZnMgO NC alloying method based on pulsed laser ablation in liquid. The limit value of homogeneous magnesium (Mg) is pushed from 37% to 62% and the optical band gap is increased to 3.7 eV with high doping efficiency (>100%). Further investigations on the lattice geometry of ZnMgO NCs indicate that all ZnMgO NCs are hexagonal wurtzite structures and the (002) and (100) peaks shift to higher diffraction angles with the increase in Mg doping content. The calculated results of the lattice constants a and c slightly decrease based on Bragg’s law and lattice geometry equations. Furthermore, the relationship between annealing temperature and the limit value of homogeneous Mg is examined and the results reveal that the latter decreases with the former because of the phase separation of MgO. A probable mechanism of zinc magnesium alloy is introduced to expound on the details of the laser-alloying process.

TOPO- and pyridine-capped cubic CdSe quantum dots were prepared, and the effect of surface ligand exchange on the photoluminescence (PL) peak shift was investigated. From the analysis of PL spectra and TEM images, it was found that the decrease in diameter in the CdSe quantum dot and redistribution of its surface electronic density play different roles in the PL peak shift. The reduction in size of CdSe by ligand exchange caused a blue shift of the PL peak due to the quantum confinement effect, whereas the redistribution of surface electronic density of CdSe by the exchange of TOPO with pyridine resulted in a red shift of 23 meV on the average for the samples investigated. The result was also supported by the XPS characterizations.