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La©B8C4+/0/− clusters adopt interesting molecular wheel structures with a dodeca-coordinated La in plane, setting a record for planar structures in chemistry. We provide new ideas and concepts for searching for planar hyper-coordinated systems.

Spinal cord injury (SCI) is one kind of severe trauma for central nervous system. Myelin debris clearance and axon regeneration are essential for nerve regeneration after SCI. Metformin, a glucose-lowering drug, has been demonstrated to promote the locomotor functional recovery after SCI. In this study, we investigated the role and molecular mechanism of metformin on myelin preservation in a rat SCI model. SCI was induced in rats by compression at T9 level using a vascular clip. We showed that administration of metformin (50 mg·kg(−1)·d(−1), ip) for 28 days significantly improved locomotor function in SCI rats. Metformin also ameliorated SCI-induced neuronal apoptosis and promoted axon regeneration in the spinal cord. Using co-immunofluorescence of IBa-1 and MBP, and luxol fasting blue (LFB) staining, we demonstrated that metformin promoted the transformation of M1 to M2 phenotype polarization of microglial cells, then greatly facilitated myelin debris clearance and protected the myelin in SCI rats. Furthermore, metformin ameliorated SCI-induced blockade of autophagic flux in the spinal cord, and enhanced the fusion of autophagosome and lysosome by inhibiting the AMPK-mTOR signaling pathway. Moreover, metformin significantly attenuated inflammatory responses in the spinal cord. In LPS-treated BV2 cells, pretreatment with metformin (2 mM) significantly enhanced autophagy level, suppressed inflammation and cell apoptosis. The protective effects were blocked in the presence of an autophagy inhibitor 3-methyladenine (3-MA, 5 mM), suggesting that the effect of metformin on autophagy in microglial cells is essential for the myelin preservation during nerve recovery. This study reveals a novel therapeutic effect of metformin in SCI recovery by regulating the activation of microglial cells and enhancing its autophagy level.

Pyroptosis is a novel programmed cell death process that promotes the release of interleukin-1β (IL-1β) and interleukin-18 (IL-18) by activating inflammasomes and gasdermin D (GSDMD), leading to cell swelling and rupture. Pyroptosis is involved in the regulation of the occurrence and development of cardiovascular and cerebrovascular diseases, tumors, and nerve injury. Diabetes is a metabolic disorder characterized by long-term hyperglycemia, insulin resistance, and chronic inflammation. The people have paid more and more attention to the relationship between pyroptosis, diabetes, and its complications, especially its important regulatory significance in diabetic neurological diseases, such as diabetic encephalopathy (DE) and diabetic peripheral neuropathy (DPN). This article will give an in-depth overview of the relationship between pyroptosis, diabetes, and its related neuropathy, and discuss the regulatory pathway and significance of pyroptosis in diabetes-associated neuropathy.

In this paper, a new methodology to build automatically 3D adapted meshes, ready for numerical simulations and directly from images, is proposed. It is based on the Immersed Image Method, which interpolates the image information on an initial mesh and combines it with parallel automatic anisotropic mesh adaptation with a control of the number of mesh nodes. Simultaneously, a smooth redistancing technique, based on the resolution of a Hamilton–Jacobi equation, is developed to produce phase functions for the objects to be detected in the image. The proposed methodology is applied on mesh generation and in multiphase flow computations based on 2D and 3D images.

The heat capacity and the electric capacitance of the black p-branes (BPB) are generally defined, then they are calculated for some special processes. It is found that the Ruppeiner thermodynamic geometry of BPB is flat. Finally, we give some discussions for the flatness of the Ruppeiner thermodynamic geometry of BPB and some black holes.

In this article, we numerically and experimentally investigate the electromagnetic responses of multiple-band reflective polarization based on complementary L-shaped metamaterial. The proposed reflective polarization converter can convert a linearly polarized wave to its cross-polarized wave at the five resonant frequencies, which is also can convert the linearly polarized wave to circularly polarized wave at other six resonant frequencies. Furthermore, the incident circularly polarized wave can be transformed into the same rotational direction at five resonant frequencies after reflection, which is different from reflection by conventional materials. Simulations are in reasonable agreements with the experimental results in the entire frequency range, and the polarization conversion ratio is over 90% for both linear and circular polarizations in simulation. © 2015 Wiley Periodicals, Inc. Microwave Opt Technol Lett 57:978–983, 2015

This paper proposes a novel direct power control (DPC) strategy for neutral-point-clamped (NPC) three-level rectifiers, to directly control the active power, the reactive power and the neutral point potential of the rectifiers by referring to three pre-calculated vector influence tables and minimizing an objective function. In the three vector influence tables, the influences of different voltage vectors on the active power, the reactive power and the neutral-point potential are shown explicitly. A conceptual description and control algorithm of the proposed controller are presented in this paper. Then, numerical simulations and experiments are carried out to validate the proposed method. Both the simulation and experimental results show that good performances during both the steady-state and transient operating conditions are achieved. As a result, the proposed strategy has been proven to be effective for NPC three-level rectifiers.

This paper investigated the dynamic pressure distribution on the plates within a wet shift clutch in hydrodynamic machineries for one engagement. The perturbation pressure model, heat conduction model and pressure calculation model excited by thermoealstic instability was developed. And wrote calculation programs with Maple 15 to analyze the influence of two kinds of typical friction materials, different thermal conductivity, different initial engagement speed on perturbation pressure amplitude and its impact on the pressure design margin and design radius. The results show that the margin can be decreased and design radius can be reduced, so power density increased. When the slipping speed is controlled within 16m /s, the radius can be reduced to about 1/2 of the original value.

We numerically investigate the influence of curved surface on the properties of metamaterial absorber in the microwave regime. It is shown that curved surface metamaterial absorber can lead to dramatic absorption increase compared with the conventional planar structure. Simulation results demonstrate that the proposed absorber can perform absorption peaks at two resonant frequencies and one resonant frequency for the TM and TE polarizations, respectively. This simple absorber is particularly desirable for various potential applications such as improving absorbance performances.

Pb1-xSrx (Zr0.53Ti0.47) O3 (PSZT) thin films have been fabricated on Pt/Ti/SiO2/Si substrate by a sol–gel method combined with a rapid thermal annealing process. The microstructure analysis of the thin films showed that the orientation ratio of (111) was 0.304，0.475 and 0.849 with x=0, 0.03, 0.08. The dielectric measurement suggested that the addition of Sr in Pb(Zr0.53Ti0.47) O3(PZT) thin films greatly improved the dielectric properties of PZT thin films. The dielectric constant for PZT thin films at a frequency of 2 kHz was 648，which was increased to 1239 when 3%at Sr was doped. Meanwhile, the dissipation factor was only increased from 0.02 to 0.03. Three kinds of piezoelectric micro-sensors have been prepared based on PSZT thin films and the sensing sensitivity of 0.017pc/uN, 0.033pc/uN, and 0.011pc/uN were realized as x increased, respectively. It indicated that micro-sensors with PSZT0.03 thin films showed better sensing property than other two.

International audience; In this paper, we introduce a new method to perform image segmentation by reinitializating an implicit function coupled to an anisotropic mesh adaptation technique. One of the advantages of such methodology is that the mesh produced can be directly used for scientific computations. In fact, finite element flow computations on images composed of multiphase structures will illustrate and validate our approach.

Some problems of the thermal-like equilibrium (TLE) universe in f(R) gravity are studied. Given the energy density of the TLE universe, the late-time form of f(R) is obtained. For the TLE universe driven by the non-relativistic matter, the energy of the apparent horizon (AH) and the ratio between it and the energy inside the AH are calculated.

International audience; In this paper, a new methodology to build automatically 3D adapted meshes, ready for numerical simulations and directly from images, is proposed. It is based on the Immersed Image Method, which interpolates the image information on an initial mesh and combines it with parallel automatic anisotropic mesh adaptation with a control of the number of mesh nodes. Simultaneously, a smooth redistancing technique, based on the resolution of a Hamilton–Jacobi equation, is developed to produce phase functions for the objects to be detected in the image. The proposed methodology is applied on mesh generation and in multiphase flow computations based on 2D and 3D images.