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In the present work, a new dynamical model with a single rigid frame driven by two pairs of vibrators, of which each pair of vibrators is engaged with each other by gear mechanism, is proposed to explore the composite synchronization of the system. The motion differential equations and vibration responses of the system are given first. The theory condition for achieving composite synchronization of the system is obtained, by using the average method to deduce the average torque balance equations of the two pairs of vibrators. According to the Hamilton’s theory, the system stability condition is presented, and it is mainly determined by the structural parameters of the system. The synchronous stable regions and stability ability versus the key parameters of the system are qualitatively discussed in numeric, and further quantitatively verified by simulations. It is shown that, in engineering, the reasonable working points of the system, should be selected in the region where the stable phase difference of the two pairs of vibrators is stabilized in the vicinity of zero. Only in this way, can the exciting forces of the two pairs of vibrators be positively superposed, and the linear motion of the system in the vertical direction be realized.

This paper aims at theoretically and experimentally investigating the controlled synchronization of four co-rotating coupled exciters in a vibrating system driven by induction motors. Using the Lagrange's equations, the motion equations of the vibrating system are derived. Combining the dynamic model of an induction motor with the dynamic model of a vibrating system, an electromechanical coupling model is developed. By virtue of the average method of modified small parameters and the Routh–Hurwitz principle, the self-synchronization criterion for four exciters and the stability criterion of synchronous states are obtained. Based on the numerical results, the stable inphase motion of four exciters fails to be implemented by means of self-synchronization, and as a result, the desired motion type of the vibrating system cannot be realized. Hence, the controlled synchronization is introduced into the vibrating system. Owing to the coupling characteristics of the vibrating system, the control challenge can be turned into a synchronization control problem between four exciters driven by induction motors. To perform the synchronized motion of zero phase differences between four exciters, sliding mode control algorithm and field-oriented control method on four induction motors are applied to develop the controlled synchronization scheme by adopting the master–slave control strategy. The stability of the closed loop system is proved by Lyapunov theorem. Experiments on a corresponding controlled synchronization bedstand are performed to examine the effectiveness of the developed controllers, including a comparison with self-synchronization method. Additionally, experimental results show the robustness of the proposed control scheme against the influence of parameter perturbations and external disturbances. The controlled synchronization method provides a novel approach to the development of vibrating machines.

The CCAAT/enhancer-binding protein (C/EBP) homologous protein (CHOP), a major transcriptional regulator of endoplasmic reticulum (ER) stress-mediated apoptosis, is implicated in lipotoxicity-induced ER stress and hepatocyte apoptosis in non-alcoholic fatty liver disease (NAFLD). We have previously demonstrated that the glucagon-like peptide-1 (GLP-1) agonist, liraglutide, protects steatotic hepatocytes from lipotoxicity-induced apoptosis by improved handling of free fatty acid (FFA)-induced ER stress. In the present study, we investigated whether CHOP is critical for GLP-1-mediated restoration of ER homeostasis and mitigation of hepatocyte apoptosis in a murine model of NASH (non-alcoholic steatohepatitis). Our data show that despite similar caloric intake, CHOP KO (CHOP−/−) mice fed a diet high in fat, fructose, and cholesterol (HFCD) for 16 weeks developed more severe histological features of NASH compared with wild-type (WT) controls. Severity of NASH in HFCD-fed CHOP−/−mice correlated with significant decrease in peroxisomal β-oxidation, and increased de novo lipogenesis and ER stress-mediated hepatocyte apoptosis. Four weeks of liraglutide treatment markedly attenuated steatohepatitis in HFCD-fed WT mice by improving insulin sensitivity, and suppressing de novo lipogenesis and ER stress-mediated hepatocyte apoptosis. However, in the absence of CHOP, liraglutide did not improve insulin sensitivity, nor suppress peroxisomal β-oxidation or ER stress-mediated hepatocyte apoptosis. Taken together, these data indicate that CHOP protects hepatocytes from HFCD-induced ER stress, and has a significant role in the mechanism of liraglutide-mediated protection against NASH pathogenesis.

An animal study in immune competent rabbits and athymic rats was conducted.

Rat LIM mineralization protein 1 (LMP‐1, an LIM domain protein) mediates bone morphogenetic protein 6 (BMP‐6) induction of bone nodule formation in fetal rat calvarial osteoblast (ROB) cultures. We have isolated the complementary DNA (cDNA) for the human homologue of LMP‐1 from an adult human heart cDNA library and showed that when overexpressed it is osteoinductive in the same culture system. The recently revised cDNA sequence of Enigma, the protein product of which binds to the insulin receptor and the tyrosine kinase receptor ret, now matches the nucleotide sequence of human LMP‐1 (hLMP‐1). A truncated, 223 amino acid (AA) LMP‐1(t) protein has identical effects as the full‐length protein, despite the deletion of the LIM domains. Two splice variants of human LMP‐1 have been detected. Human LMP‐2 has a 119‐base pair (bp) deletion between bp 325 and 444 and a 17‐bp insertion at bp 444. The resulting derived protein contains 423 AA with the LIM domains intact and does not induce bone formation when overexpressed in ROB cultures. Human LMP‐3 has the same 17 nucleotide insertion at bp 444, resulting in a shift in the reading frame that causes a stop codon to occur at bp 505‐507. The resulting 153 AA protein does not have the LIM domains, but overexpression of hLMP‐3 induces bone formation in osteoblast cultures. These findings suggest that the LIM domains are not required for LMPs to induce bone formation. In addition, a small region (36 AA) of the LMP‐1 protein may be required for bone formation.

A PCP-type catalyst was prepared and examined within the context of intramolecular Heck reactions. A substrate possessing a 1,4-diene system effectively poisoned the PCP catalyst leading to no reaction. This behavior contrasts with the typical palladium(0) catalyst system.

A posterior arthrodesis animal model using local expression of a newly discovered osteoinductive protein delivered in bone marrow cells.

A finite element model has been developed for analysis of heterogeneous media, in which second phase inclusions are arbitrarily dispersed within a matrix. A mesh generator based on Dirichlet tessellation, discretizes the heterogeneous domain, accounting for the arbitrariness in location, shape and size of the second phase. This results in a network of convex “Voronoi” polygons which form the elements in a finite element mesh. An assumed stress hybrid formulation has been implemented for accommodating arbitrary multi-sided elements in the finite element model. Composite element formulations have been developed to incorporate the effect of second phase within each element. Formulations have been developed for thermo-elasticity, micropolar elasticity and elasto-plasticity.

The article presents excerpts from the keynote speech delivered by Liu Yunshan, a member of the Standing Committee of the Political Bureau of the Communist Party of China (CPC) Central Committee, at the Europe High-Level Political Parties Forum held in Suzhou, China in April 2013, in which he addressed joint effort areas for China and Europe, including interdependence and cultural exchanges.

An excerpt from a speech given by Chinese President Xi Jinping related to goals of Chinese government for improving the economic condition at the Fourth China-Europe High-Level Political Parties Forum held in China in 2013 is presented.

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