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To handle the suspended rotor speed self-identification problem of a bearingless induction motor (BL-IM), a sensorless control strategy based on fuzzy PI fractional model reference adaptive system (MRAS) is proposed. First, based on the flux linkage error, fractional MRAS adaptive law is designed to accelerate the response speed of the controlled object, and Lyapunov theorem is used to prove the stability of the adaptive law. Then, the fuzzy control rules in the fuzzy PI controller are used to adjust PI parameters of adaptive law online in real time. Finally, the speed under no-load operation, abrupt speed change and abrupt change of load is estimated and sensorless control is realized. The simulation and experimental results show that the proposed fuzzy PI fractional MRAS control system of the BL-IM can not only effectively realize self-identification of speed under no-load, speed change and abrupt change of load, but also have good suspension characteristics of the motor suspended rotor, realizing high reliability and low costs of BL-IM. [ABSTRACT FROM AUTHOR]

The electrochemical carbon dioxide reduction reaction (CO2RR) holds great promise for mitigating CO2 emission and simultaneously generating high energy fuel. However, it remains a great challenge to reduce CO2 to C2 products due to the lack of highly efficient catalysts. Herein, by means of a particle swarm optimization search and comprehensive density functional theory (DFT) computations, we predicted a hitherto unknown Cu2N monolayer with planar hexacoordinate Cu and tetracoordinate N atoms as a CO2RR catalyst. Our results revealed that the Cu2N monolayer shows outstanding stability and intrinsic metallicity. Interestingly, the as-designed Cu2N monolayer exhibits superior CO2RR catalytic performance with a rather low limiting potential (−0.33 V), resulting in the formation of a C2H4 product with a small kinetic barrier (0.55 eV) for the coupling between *CH2 and a CO molecule. Strikingly, the N atoms within the Cu2N monolayer were revealed to be the CO2RR active sites due to their significant binding strength with the CO2RR species and their significant spin moments. Our findings not only propose a useful roadmap for the discovery of 2D hypercoordinate materials, but also provide cost-effective opportunities for advancing sustainable CO2 conversion. [ABSTRACT FROM AUTHOR]

Abstract Background In E. coli, the Min operon (MinCDE) plays a key role in determining the site of cell division. MinE oscillates from the middle to one pole or another to drive the MinCD complex to the end of the cell. The MinCD complex prevents FtsZ ring formation and the subsequent cell division at cell ends. In Arabidopsis thaliana, a homologue of MinD has been shown to be involved in the positioning of chloroplast division site. Results To learn whether the MinD homologue in plants is functional in bacteria, AtMinD was expressed in E. coli. Surprisingly, AtMinD can rescue the minicell phenotype of E. coli HL1 mutant (ΔMinDE) in the absence of EcMinE. This rescue requires EcMinC. AtMinD was localized to puncta at the poles of E. coli cells and puncta in chloroplasts without oscillation. AtMinD expressed in the HL1 mutant can cause a punctate localization pattern of GFP-EcMinC at cell ends. Yeast two hybrid and BiFC analysis showed that AtMinD can interact with EcMinC. Conclusion Similar to the MinD in Bacillus subtilis, AtMinD is localized to the polar region in E. coli and interacts with EcMinC to confine EcFtsZ polymerization and cell division at the midpoint of the cell.

Sustainable production of high-value carbon-based fuels and chemicals through electrochemical CO reduction (COR) under mild conditions is a promising alternative to the traditional Fischer–Tropsch process that requires high energy input and large-scale reactors. However, the COR process suffers from the low activity and poor selectivity of the currently employed electrocatalysts, greatly hampering its large-scale application. Herein, by means of comprehensive swarm-intelligence structure search and first-principles computations, we identify an ideal electrocatalyst for COR, i.e., a metallic Cu2B2 monolayer with planar heptacoordinate copper and planar pentacoordinate boron. Our results reveal that the predicted Cu2B2 monolayer exhibits superior thermal and dynamic stability and holds promise for experimental realization. More importantly, this catalyst could effectively reduce CO to ethanol through the "carbene" mechanism with a low limiting potential (−0.59 V) and a small barrier for C–C coupling (0.41 eV). Our work is the first report on the as-designed electrocatalyst with planar hypercoordinate motifs for CO reduction to C2 products, which not only widens the potential application of hypercoordinate 2D materials, but also opens up a new and promising avenue for converting abundant industrial CO to value-added ethanol. [ABSTRACT FROM AUTHOR]

Microglia are the inherent immune effector cells in the central nervous system (CNS), are activated rapidly when the CNS is stimulated by ischaemia, infection, injury, etc. and participate in and aggravate the development of inflammatory reactions in the CNS. During the process of microglial activation, inflammatory factors such as TNF-α and IL-1β and an abundance of reactive oxygen species (ROS)/reactive nitrogen species (RNS), are released by damaged nerve cells. LXW7 is a small molecule peptide and specifically binds with integrin αvβ3. Cerium oxide nanoparticles (nanoceria) are strong free radical scavengers and are widely used in many studies. In this research, a model of inflammation was established using lipopolysaccharide (LPS) to induce BV2 microglia activation, and the effects of CeO2@PAA (synthetic nanoscale cerium oxide particles), LXW7 and CeO2@PAA-LXW7 were evaluated. We detected the expression level of inflammatory factors, the release of NO in BV2 cells and the generation of intracellular ROS. The expression levels of focal adhesion kinase (FAK) and signal transducer and activator of transcription 3 (STAT3) and their phosphorylated proteins were detected in BV2 microglia. We found that CeO2@PAA, LXW7 and CeO2@PAA-LXW7 all effectively inhibited the activation of BV2 microglia, reduced the production of cytokines and the release of NO and reduced the production of intracellular ROS. The three treatments all inhibited the phosphorylation of FAK and STAT3 in BV2 microglia. Regarding these effects, CeO2@PAA-LXW7 was more effective than the other two monotherapies. Our data indicate that CeO2@PAA, LXW7 and CeO2@PAA-LXW7 can exert a neuroprotective function by inhibiting the inflammatory response of LPS-induced BV2 microglia. LXW7 may inhibit the activation of FAK and STAT3 signals in combination with integrin αvβ3 to restrain neuroinflammation and the antioxidative stress effect of cerium oxide; hence, CeO2@PAA-LXW7 can exert a more robust anti-inflammatory and neuroprotective effect via synergistically suppressing the ability of LXW7 to influence the integrin pathway and the free radical-scavenging ability of CeO2@PAA. [ABSTRACT FROM AUTHOR]

Mechanical metamaterials are often designed with particular properties for specific load‐bearing functions. Alternatively, this study aims to create a class of active lattice metamaterials, dubbed self‐activated solids, that can learn desired stiffness tensors from the elastic deformations they experienced, a crucial feature to improve the performance, efficiency, and functionality of materials. Artificial adaptive matters that combine sensory, control, and actuation elements can offer appealing solutions. However, challenges still remain: The designs will rely on accurate off‐line and global computations, as well as intricate coordination among individual elements. Here, a simple online and local learning strategy is initiated based on contrastive Hebbian learning to gradually guide self‐activated solids to possess sought‐after stiffness tensors autonomously and reversibly. During learning, the bond stiffness of the active lattice varies depending only on its local strain. The numerical tests show that the self‐activated solid can not only achieve the desired bulk, shear, and coupling moduli but also manifest uni‐mode and bi‐mode extremal materials by itself after experiencing the corresponding elastic deformations. Further, the self‐activated solid can also achieve the desired time‐varying moduli when exposed to temporally different loads. The design is applicable to any lattice geometries and is resistant to damage and instabilities. The material design approach and the physical learning strategy suggested can benefit the design of autonomous materials, physical learning machines, and adaptive robots. [ABSTRACT FROM AUTHOR]

Highlights • Vulnerability assessment index system suitable for urban power grid is established based on combination evaluation. • The quantitative analysis of various types of indicators in the same system has been realized. • The objective characteristics of indexes and the tendency of expert evaluation are taken into full consideration by using learning ability of ANN. Abstract As urban power grid is getting more and more complex, it is necessary to improve the original evaluation method and also a more convenient and accurate vulnerability assessment of urban power grid is needed. Firstly, the evaluating vulnerability index system of urban power grid is established by Analytic Hierarchy Process (AHP) from four aspects of composition of power supply, grid structure, grid operation and important transmission channels. Secondly, according to the effect and position of index in evaluation system, the weights of different indexes are calculated by using the Artificial Neural Network (ANN). Thirdly, aiming at the problem of different dimensions of input indexes, a nondimensionalized scoring standard is proposed to form a complete assessment system. Finally, the vulnerability assessment of urban power grid is carried out by taking a city as an example. The paper puts forward the weaknesses and defects of the urban power grid after analyzing the results, which lays a theoretical foundation for further optimization and upgrading. [ABSTRACT FROM AUTHOR]

CeO2 nanoparticles (nanoceria) have been used in many studies as a powerful free radical scavenger, and LXW7, a small-molecule peptide, can specifically target the integrin αvβ3, whose neuroprotective effects have also been demonstrated. The objective of this study is to observe the neuroprotective effect and potential mechanism of CeO2@PAA-LXW7, a new compound that couples CeO2@PAA (nanoceria modified with the functional group of polyacrylic acid) with LXW7 via a series of chemical reactions, in H2O2-induced NGF-differentiated PC12 cells. We examined the effects of LXW7, CeO2@PAA, and CeO2@PAA-LXW7 on the viability of primary hippocampal neurons and found that there was no significant difference under control conditions, but increased cellular viability was observed in the case of H2O2-induced injury. We used H2O2-induced NGF-differentiated PC12 cells as the classical injury model to investigate the neuroprotective effect of CeO2@PAA-LXW7. In this study, LXW7, CeO2@PAA, and CeO2@PAA-LXW7 inhibit H2O2-induced oxidative stress by reducing the production of reactive oxygen species (ROS) and regulating Bax/Bcl-2, cleaved caspase-3 and mitochondrial cytochrome C (cyto C) in the apoptotic signaling pathways. We found that the levels of phosphorylation of focal adhesion kinase (FAK) and of signal transducer and activator of transcription 3 (STAT3) increased significantly in H2O2-induced NGF-differentiated PC12 cells, whereas LXW7, CeO2@PAA, and CeO2@PAA-LXW7 suppressed the increase to different degrees. Among the abovementioned changes, the inhibitory effect of CeO2@PAA-LXW7 on H2O2-induced changes, including the increases in the levels of p-FAK and p-STAT3, is more obvious than that of LXW7 or CeO2@PAA alone. In summary, these results suggest that integrin signaling participates in the regulation of apoptosis via the regulation of ROS and of the apoptosis pathway in H2O2-induced NGF-differentiated PC12 cells. LXW7, CeO2@PAA, and CeO2@PAA-LXW7 can play neuroprotective roles by counteracting the oxidative stress and apoptosis induced by H2O2 in NGF-differentiated PC12 cells. CeO2@PAA-LXW7 exerting a more powerful synergistic effect via the conjunction of LXW7 and CeO2@PAA. [ABSTRACT FROM AUTHOR]

The drug-serum albumin interaction plays a dominant role in drug efficacy and disposition. The glycation of serum albumin that occurs during diabetes may affect its drug-binding properties in vivo. In order to evaluate the interactivity characteristics of cyanidin-3- O-glucoside (C3G) with human serum albumin (HSA) and glycated human serum albumin (gHSA), this study was undertaken using multiple spectroscopic techniques and molecular modeling analysis. Time-resolved fluorescence and the thermodynamic parameters indicated that the quenching mechanism was static quenching, and hydrogen bonding and Van der Waals force were the main forces. The protein fluorescence could be quenched by C3G, whereas the polarity of the fluorophore was not obviously changed. C3G significantly altered the secondary structure of the proteins. Furthermore, the interaction force that existed in the HSA-C3G system was greater than that in the gHSA-C3G system. Fluorescence excitation emission matrix spectra, red edge excitation shift, Fourier transform infrared spectroscopy and circular dichroism spectra provided further evidence that glycation could inhibit the binding between C3G and proteins. In addition, molecular modeling analysis supported the experimental results. The results provided more details for the application of C3G in the treatment of diabetes. [ABSTRACT FROM AUTHOR]

[Display omitted] • High-valence Zr-incorporated Ni 2 P is fabricated through the hydrothermal and subsequently phosphorization method. • Zr 0.1 Ni 1.9 P exhibits remarkable HER and OER performances with the excellent long-term durability more than 100 h. • DFT results confirm that the incorporation of Zr effectively regulates the electronic state and boosts the intrinsic activity of catalyst. Expediting the kinetics of electrochemical hydrogen (HER) and oxygen evolution reaction (OER) is a critical segment in water electrolysis, however, it remains a great challenge. Here, we address this issue via incorporating high valence Zr into Ni 2 P (Zr x Ni 2-x P) to lower the energy barrier of reaction intermediates. The as-prepared Zr 0.1 Ni 1.9 P catalyst exhibits unexceptionable catalytic activities for both HER and OER. It possesses low overpotential of 68 and 239 mV for the HER and OER at the current density of 10 mA cm−2 (j 10), respectively, with the excellent long-term durability more than 100 h. Particularly, the catalytic activity of Zr 0.1 Ni 1.9 P is superior to that of noble metal catalysts (Pt/C and RuO 2) at high current density (> j 300). Furthermore, the electrolytic cell achieves a low potential of only 1.54 V at j 10 to drive overall water splitting in alkaline medium. Density functional theory (DFT) calculations reveal that high-valence Zr incorporating promotes the adsorption and dissociation processes of H 2 O to boost alkaline HER and decreases the free energy change of the potential-determining step (O*→OOH*) to facilitate the OER process. This strategy of incorporating high valence Zr to boost reaction kinetics provides a new avenue for designing high performance electrocatalysts. [ABSTRACT FROM AUTHOR]