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Intercalation of insulating materials between epitaxial graphene and the metal substrates is highly demanded to restore the intrinsic properties of graphene, and thus essential for the graphene-based devices. Here we demonstrate a successful solution for the intercalation of hafnium oxide into the interface between full-layer graphene and Ir(111) substrate. We first intercalate hafnium atoms beneath the epitaxial graphene. The intercalation of the hafnium atoms leads to the variation of the graphene moiré superstructure periodicity, which was characterized by low-energy electron diffraction (LEED) and low-temperature scanning tunneling microscopy (LT-STM). Subsequently, we introduce oxygen into the interface, resulting in oxidization of the intercalated hafnium. STM and Raman characterizations reveal that the intercalated hafnium oxide layer could effectively decouples the graphene from the metallic substrate, while the graphene maintains its high quality. Our work suggests a high-k dielectric layer has been successfully intercalated between high-quality epitaxial graphene and metal substrate, providing a platform for applications of large-scale, high-quality graphene for electronic devices.

Backgrounds A major side effect of statin, a widely used drug to treat hyperlipidemia, is skeletal myopathy through cell apoptosis. The aim of this study is to investigate the roles of microRNA in statin-induced injury. Methods Apolipoprotein E knockout (ApoE-/-) mice were administered with simvastatin (20 mg/kg/day) for 8 weeks. Exercise capacity was evaluated by hanging grid test, forelimb grip strength, and running tolerance test. Results In cultured skeletal muscle cells, statin increased the levels of miR-1a but decreased the levels of mitogen-activated protein kinase kinase kinase 1 (MAP3K1) in a time or dose dependent manner. Both computational target-scan analysis and luciferase gene reporter assay indicated that MAP3K1 is the target gene of miR-1a. Statin induced cell apoptosis of skeletal muscle cells, but abolished by downregulating of miR-1a or upregulation of MAP3K1. Further, the effects of miR-1a inhibition on statin-induced cell apoptosis were ablated by MAP3K1 siRNA. In ApoE-/- mice, statin induced cell apoptosis of skeletal muscle cells and decreased exercise capacity in mice infected with vector, but not in mice with lentivirus-mediated miR-1a gene silence. Conclusion Statin causes skeletal injury through induction of miR-1a excessive expression to decrease MAP3K1 gene expression.

Marein, an active component of the Coreopsis tinctoria Nutt. plant, is known to improve diabetic nephropathy (DN). However, its anti-diabetic functions in DN and potential mechanisms remain unclear. The aim of this study was to elucidate the effects and mechanisms of Marein in diabetic db/db mice with DN, and in high glucose-treated HK-2 cells. In vivo, treating diabetic db/db mice with Marein for 12 consecutive weeks restored diabetes-induced hyperglycemia and dyslipidemia, and ameliorated renal function deterioration, glomerulosclerosis, and renal ectopic lipid deposition. Marein exerted renoprotective effects by directly inhibiting renal tubule sodium glucose transporter 2 (SGLT2) expression, and then activating the AMP-activated protein kinase (AMPK)/acetyl CoA carboxylase (ACC)/peroxisome proliferator-activated receptor-γ coactivator 1α (PGC-1α) pathway in db/db mice. Meanwhile, Marein ameliorated fibrosis and inflammation by suppressing the pro-inflammatory factors interleukin-6 (IL-6) and monocyte chemotactic protein-1 (MCP-1), and expression of the extracellular matrix proteins, fibronectin (FN) and collagen 1 (COL1) in diabetic mice. In vitro, MDCK monolayer cells were established to explore the characteristics of Marein transmembrane transport. Marein was found to be absorbed across the membrane at a medium level that involved active transport and this was mediated by SGLTs. In HK-2 cells, Marein decreased uptake of the fluorescent glucose analog, 2-NBDG, by 22 % by inhibiting SGLT2 expression. In high glucose-treated HK-2 cells, Marein decreased SGLT2 expression and increased phosphorylated (p)-AMPK/p-ACC to improve high glucose-induced cellular dysfunction. Furthermore, Marein treatment decreased SGLT2 expression in SGLT2-overexpressing HK-2 cells. In addition, molecular docking and dynamics analysis revealed that SGLT2 was a direct target of Marein. Collectively, our results demonstrated that Marein ameliorates DN by inhibiting renal SGLT2 and activating p-AMPK, suggesting Marein can potentially prevent DN by suppressing renal SGLT2 expression directly.

Flavanomarein (FM) is a major natural compound of Coreopsis tinctoria Nutt with protective effects against diabetic nephropathy (DN). In this study, we investigated the effects of FM on epithelial-mesenchymal transition (EMT) in high glucose (HG)-stimulated human proximal tubular epithelial cells (HK-2) and the underlying mechanisms, including both direct targets and downstream signal-related proteins. The influence of FM on EMT marker proteins was evaluated via western blot. Potential target proteins of FM were searched using Discovery Studio 2017 R2. Gene Ontology (GO) analysis was conducted to enrich the proteins within the protein-protein interaction (PPI) network for biological processes. Specific binding of FM to target proteins was examined via molecular dynamics and surface plasmon resonance analyses (SPR). FM promoted the proliferation of HK-2 cells stimulated with HG and inhibited EMT through the Syk/TGF-β1/Smad signaling pathway. Spleen tyrosine kinase (Syk) was predicted to be the most likely directly interacting protein with FM. Combined therapy with a Syk inhibitor and FM presents significant potential as an effective novel therapeutic strategy for DN.

For the problem of the vehicle parts monitoring in the internet of vehicle, the service technology is proposed to access the detail components through the common gateway interface technology. The information transmission is managed using the common gateway interface and interface parts for docking, and the monitoring of detail parts is made by the bus integration monitoring. IPv6 virtual network address information transmission is used to avoid the hidden dangers of IPv4 address depletion, and the virtual and independent IPv6 address is transferred with the part number in the common gateway interface to achieve a wide geographical access. In order to achieve real-time information exchange and robustness, the real-time transport protocol and real-time transport control protocol is used to assure smaller transmission delay and less packet loss rate. The test results show that the average response time is no more than 85 nanoseconds and the accuracy of information transfer is not less than 98.2%, and the results meets the needs of the most environmental, and the program is viable in practice.

In order to improve the monitoring efficiency of port coastal ship, and improve the ability of coastal management, the port coastal ships web remote video monitoring system is designed and realized. The GPRS/UDP technology is used to transmit the ship videos to the server in real time. The client terminal and visual monitoring terminal are established, and the ship monitoring personnel can enter the WEB monitoring platform with different permissions. The network browse module, scheduling module, monitoring terminal module are designed, the port coastal ships video data are monitored and processed, the automatic alarm module based on the density ratio is designed. The intelligent early warning of port coastal ships density is obtained. The application experiment is implemented on the port coastal entrance, experiment results show that this system can realize the remote video Web monitoring of ships and intelligent early warning, and it has good effect in application.

Based on the System Engineering theory, the main factors that lead to the vibration in high-speed cutting were presented, which were the structure of the high-speed machine tool, the component of the tool system, the characters of the workpiece material, the choosing of the cutting parameters and the machining environment conditions. The forming mechanism of the vibration in high-speed machining was discussed, according to the characters of controlling each part of the high-speed machining system. The main controlling strategy and improving paths of the active vibration control in high-speed machining were brought forward.

Studying on the KM4030 toolholder/spindle interface, through changing some factors such as magnitude of interference, clamping force, etc. the effects of different parameters on the performance of toolholder/spindle connection system were researched by means of the finite element method (FEM). The KM toolholder/spindle interface belongs to the highly nonlinear problem caused by interference fit and elastic coulomb friction. The distribution situation of the contact stress and elastic deformation was also given out based on the precise simulation results and the optimum magnitude of interference as well as clamping force was also recommended. It was expected the results could be used as theoretical basis and technical guide for application of KM tool shank in high speed machining (HSM).