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This article presents an experiment of rocket-triggered lightning to 10 kV power distribution lines and the characteristics of lightning current at Guangzhou Field Experiment Site for Lightning Research and Testing during 2018–2019. The return strokes (RSs) current of the triggered-lightning flashes in this study exhibits a shorter half-peak width and similar risetime and peak current compared with those of subsequent strokes current from natural lightning. The peak current of RSs shows strong power function correlations with charge transfer within 1 ms and action integral within 1 ms of RSs, with R2 of 0.80 and 0.92, respectively. Besides, the peak current of RSs is proportional to the average rate rise of RSs (dI/dt). We recommend the double HEIDLER function to simulate the RS current and provide accurate raw data for the study of lightning protection.

The impulse grounding performance of distribution lines tower is the key factor to lightning protection. Few field high-current impulse test researches are conducted on distribution line tower. In this paper, we used a mobile high-current impulse generator to conduct test on a 10 kV distribution line tower. The peak value of the current injection is 6 kA to 16 kA. The impulse impedance and the surface potential distribution are measured and analyzed. Based on the CDEGS software, an equivalent modeling of the experiment was carried out. The influence of soil ionization was taken into account by the method of changing the conductor radius through two rounds of calculation. The simulation and measured results were basically consistent. Experiments have shown that the soil ionization effect has an important impact on lightning performance of distribution line tower. The graphite earthing modules (GEMs) and pulling wires can significantly reduce the impulse impedance of the tower. The potential rise of the earth surface at a distance of 30 m from the tower can reach 1 kV at peak, under an injection of 7.15 kA.

Soybean is an important crop, so it is very important to forecast soybean price trend, which can stabilize the market. This paper presents a Synthesis Method with Multistage Model (SMwMM) in order to identify and forecast soybean price trend in China. In the previous work,Toeplitz Inverse Covariance-based Clustering(TICC) has been applied to cluster the prices of four variables. The research have found that there are four patterns in soybean market price, which could be explained by economic theory. This paper consider four patterns as market risk levels. Based on the clustering results, we used Long short-term memory(LSTM) to forecast the prices of these four variables. Multivariate long short-term memory(MLSTM) is then used to classify soybean price to determine level of risk . Experimental results show that :(1)The LSTM model has achieved great fitting effect and high prediction accuracy;(2) The performance of MLSTM-FCN and MALSTM-FCN is better than that of LSTM-FCN and ALSTM-FCN. Furthermore,MALSTM-FCN had the higher accuracy than MLSTM-FCN, which reached 76.39%.

The thermal behaviour of the surge arrester is vital to assess its operational condition. The surge arrester usually shows a process of temperature rising during a long-term operation, particularly after subjecting to a surge. Therefore, the research on the temperature characteristics of ZnO arresters contributes to achieve the goal of the performance changes of the ZnO arresters over different temperatures. In this study, based on four types of ZnO arresters from different factories, the variation of the volt–ampere curve, DC characteristic parameters and non-linear coefficient of the whole ZnO arrester at different temperatures were analysed. The relationship between the temperature and non-linear coefficients was obtained through the method of the extraction of the non-linear coefficients. Through the multiple impulse current tests, the temperature of the arrester was well calculated by measuring the corresponding volt–ampere curve, and the relationship between the surface temperature and V–I characteristics of the arrester is verified by the impulse test results. The obtained results provide a new idea for the application of the surface temperature of the arrester in the performance monitoring of the arrester.

The host–guest interactions between baicalein (BALE) and cucurbit[8]uril (Q[8]) and the corresponding properties of the inclusion complex were studied using 1H NMR, IR and UV–vis spectroscopy and DTA. The results showed that BALE forms an inclusion compound (1:1) with Q[8], and the properties of baicalein are changed by cucurbit[8]uril.

Two special cases of dart leader propagation were observed by the high-speed camera in the leader/return stroke sequences of a classical triggered lightning flash and an altitude-triggered lightning flash, respectively. Different from most of the subsequent return strokes preceded by only one leader, the return stroke in each case was preceded by two leaders occurring successively and competing in the same channel, which herein is named leader-chasing behavior. In one case, the polarity of the latter leader was opposite to that of the former leader and these two combined together to form a new leader, which shared the same polarity with the former leader. In the other case, the latter leader shared the same polarity with the former leader and disappeared after catching up with the former leader. The propagation of the former leader in this case seems not to be significantly influenced by the existence of the latter leader.

Macrophages are involved in the early inflammation during tissue repair and play a distinctive role in maintaining the stability of the tissue microenvironment. However, it is still very difficult to accurately regulate the phenotypic transformation of macrophages during bone repair. The current study innovatively used 4-octyl itaconate (OI), a cell-permeable derivative of an endogenous anti-inflammatory metabolite itaconate (IA), to regulate the polarization of macrophages and enhance the quality of bone repair. Chitosan (CS) was selected as a bridge in coating OI on demineralized bone matrix (DBM) scaffold to generate three-dimensional (3D) bone integration scaffold (OI/CS/DBM scaffold). Whether this metabolite derivative can exert the same anti-inflammatory effect as the metabolite itself was validated both in vitro and in vivo. In vitro cellular results showed that both OI and OI/CS/DBM scaffold could promote the formation of anti-inflammatory phenotype of macrophages, and the osteogenic differentiation of mesenchymal stem cells (MSCs) was indirectly enhanced by macrophage supernatant medium. In vivo studies of a rat skull defect model further proved that the OI/CS/DBM scaffold could improve the bone integration. In this study, the OI/CS/DBM scaffold was successfully fabricated as a vehicle for delivering OI, which was proved to have the ability to promote bone integration by regulating early inflammation. The present results may provide a novel method to improve bone repair with metabolites derivative to regulate the inflammation.

To build a three-dimensional co-culture model in a microfluidic device for cancer research and evaluate its feasibility by investigating cancer stem-like cells (SCs) induced migration of human umbilical vein endothelial cells (ECs).The microfluidic device provided two-dimensional and three-dimensional (2D/3D) culture and co-culture environments without affecting cell viability. The device also provided an effective concentration for the chemiotaxis of cells, and to support real-time monitoring of cell behavior. In this model, SCs significantly increased the migration area of ECs with a hepatocarcinoma cell line (MHCC97H; MCs). The presence of ECs also induced both MCs and SCs invasion into Matrigel. The migration area of MCs and SCs significantly increased when co-cultured with ECs.This 3D co-culture microfluidic model is a suitable model in cancer research. Compared with MCs, SCs had greater potential in inducing EC migration and interacting with ECs.

Metal-organic frameworks (MOFs) have drawn increasing attentions as promising candidates for functional devices. Herein, we present MOF films in constructing memory devices with alcohol mediated resistance switching property, where the resistance state is controlled by applying alcohol vapors to achieve multilevel information storage. The ordered packing mode and the hydrogen bonding system of the guest molecules adsorbed in MOF crystals are shown to be the reason for the alcohol mediated electrical switching. This chemically mediated memory device can be a candidate in achieving environment-responsive devices and exhibits potential applications in wearable information storage systems. ASTAR (Agency for Sci., Tech. and Research, S’pore) MOE (Min. of Education, S’pore) Accepted version

A facile encapsulation strategy for the preparation of metal layer/metal–organic framework (metal/MOF) hybrid thin films, by alternately growing MOF thin films and sputter-coating metal layers, is reported. The controlled species of the MOF thin films and metal layers, as well as the designed thickness of MOF thin films, endow the resulting hybrid thin films with improved functional and design flexibility. Importantly, the metal/MOF hybrid thin films, with well-defined sandwich structures, exhibit excellent selective catalytic activity, derived from MOFs acting as molecular sieves and the metal layers providing active sites.

Chain-like MoS2 assemblies consisting of hexagonal MoS2 nanoparticles (20–60 nm) have been successfully synthesized in a Triton X-100/cyclohexane/hexanol/water W/O reverse microemulsion in the presence of (NH4)2MoS4 as the molybdenum source and NH2OH·HCl as the reducing agent. The products were characterized by X-ray powder diffraction (XRD), transmission electron microscopy (TEM) and UV-vis diffuse reflectance absorption spectra. The influence of synthetic parameters such as acidity, water/oil ratio (ω0), aging time and annealing temperature on the formation of MoS2 assemblies was investigated. TEM analysis showed that these synthetic factors played important roles in controlling the size of MoS2 nanoparticles and the length of the chain-like MoS2 assemblies. XRD analysis indicated that the well-crystallized MoS2 nanoparticles could be obtained by annealing the precursors at 700°C for 2 h under a flow of N2 atmosphere. In addition, the as-prepared chain-like MoS2 nanoparticles exhibited excellent photocatalytic H2 activity in Ru(bpy)32+-MoS2-H2A three-component molecular systems under visible light irradiation.

The site‐selective reaction of a multifunctional linear molecule requires a suitable catalyst possessing both uniform narrow channel to limit the molecule rotation and a designed active site in the channel. Recently, nanoparticles (NPs) were incorporated in metal–organic frameworks (MOFs) with the tailorable porosity and ordered nanochannel, which makes these materials (NPs/MOFs) highly promising candidates as catalytic nanoreactors in the field of heterogeneous catalysis. Inspired by a “Gondola” sailing in narrow “Venetian Canal” without sufficient space for a U‐turn, a simple heterogeneous catalyst based on NPs/MOFs is developed that exhibits site‐selectivity for the oxidation of diols by restricting the random rotation of the molecule (the “Gondola”) in the limited space of the MOF channel (the narrow “Venetian Canal”), thereby protecting the middle functional group via steric hindrance. This strategy is not limited to the oxidation of diols, but can be extended to the site‐selective reaction of many similar multifunctional linear molecules, such as the reduction of alkadienes. Accepted version

To investigate the effect of mechano-growth factor (MGF) on the differentiation of human bone marrow-derived mesenchymal stem cells (hBMSCs) in vitro. Flow cytometry assay identified the isolated cells were human bone marrow mesenchymal stem cells, which had differentiation ability when cultured with specific induction culture media. Alizarin Red S, Oil Red O and Alcian Blue staining showed osteogenic, adipogenic and chondrogenic differentiation were significantly increased after hBMSCs were treated with MGF E peptide. Collagen II expression was considerably increased after hBMSCs were induced with chondrogenic induction culture medium supplemented with TGF-β3 and MGF E peptide. Overexpression of MGF by an expression plasmid further confirmed the MGF could enhance tri-lineage differentiation of hBMSCs. Moreover, we found that hBMSCs proliferation rate was decreased and G1 phase of the cell cycle was lengthened after MGF treatment when compared to the control group. MGF can enhance differentiation of hBMSCs during specific induction culture media induction by lengthening G1 phase of cell cycle.

Tendons and ligaments exhibit limited regenerative capacity following injury, with damaged tissue being replaced by a fibrotic scar. The physiological role of scar tissue is complex and has been studied extensively. In this study, we demonstrate that rat tendons contain a unique subpopulation of cells exhibiting stem cell characteristics, including clonogenicity, multipotency, and self-renewal capacity. Additionally, these putative stem cells expressed markers consistent with neural crest stem cells (NCSCs). Using immunofluorescent labeling, we identified P75(+) (p75 neurotrophin receptor) cells in the perivascular regions of the native rat tendon. Importantly, P75(+) cells were frequently localized near vascular cells and increased in number within the peritenon after injury. Ultrastructural analysis showed that perivascular cells detached from vessels in response to injury, migrated into the interstitial space, and deposited extracellular matrix. Characterization of P75(+) cells isolated from the scar tissue indicated that this population also expressed the NCSC markers, Vimentin, Sox10, and Snail. In conclusion, our results suggest that neural crest-like stem cells of perivascular origin reside within the rat peritenon and give rise to scar-forming stromal cells following tendon injury.

Induced pluripotent stem cells (iPSCs) hold great potential for cell therapy and tissue engineering. Neural crest stem cells (NCSCs) are multipotent that are capable of differentiating into mesenchymal lineages. In this study, we investigated whether iPSC-derived NCSCs (iPSC-NCSCs) have potential for tendon repair. Human iPSC-NCSCs were suspended in fibrin gel and transplanted into a rat patellar tendon window defect. At 4 weeks post-transplantation, macroscopical observation showed that the repair of iPSC-NCSC-treated tendons was superior to that of non-iPSC-NCSC-treated tendons. Histological and mechanical examinations revealed that iPSC-NCSCs treatment significantly enhanced tendon healing as indicated by the improvement in matrix synthesis and mechanical properties. Furthermore, transplanted iPSC-NCSCs produced fetal tendon-related matrix proteins, stem cell recruitment factors, and tenogenic differentiation factors, and accelerated the host endogenous repair process. This study demonstrates a potential strategy of employing iPSC-derived NCSCs for tendon tissue engineering.

Prediction of proteasomal cleavage sites has been a focus of computational biology. Up to date, the predictive methods are mostly based on nonlinear classifiers and variables with little physicochemical meanings. In this paper, the physicochemical properties of 14 residues both upstream and downstream of a cleavage site are characterized by VHSE (principal component score vector of hydrophobic, steric, and electronic properties) descriptors. Then, the resulting VHSE descriptors are employed to construct prediction models by support vector machine (SVM). For both in vivo and in vitro datasets, the performance of VHSE-based method is comparatively better than that of the well-known PAProC, MAPPP, and NetChop methods. The results reveal that the hydrophobic property of 10 residues both upstream and downstream of the cleavage site is a dominant factor affecting in vivo and in vitro cleavage specificities, followed by residue's electronic and steric properties. Furthermore, the difference in hydrophobic potential between residues flanking the cleavage site is proposed to favor substrate cleavages. Overall, the interpretable VHSE-based method provides a preferable way to predict proteasomal cleavage sites.