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Aged nonhuman primate (NHP) models are of great value for studying the pathology of metabolic heart diseases and developing therapeutic strategies. In this study, aged male cynomolgus monkeys were fed a regular diet or a high-fat/high-sugar diet (HFSD) for 8 months. Metabolic disorders were diagnosed by 1H-NMR and serum biochemistry, and cardiac function was evaluated by echocardiography. Our results showed that serum metabolic profiles were altered in aged monkeys fed a HFSD, in line with aortic tissue damage, cardiac remodeling, and contractile dysfunction. This aged monkey model significantly increased expression of proinflammatory cytokines and altered expression and phosphorylation of intracellular signaling proteins in the heart, as compared to aged monkeys on a regular diet. Furthermore, the animals demonstrated increased phosphorylation of cardiac myofilament proteins which are causatively associated with decreased myofilament contractility. We conclude that the aged monkey model fed a HFSD exhibits metabolic disorders and cardiac contractile dysfunction.

In order to investigate the mechanism of burr formation and burr minimization, experiment and finite element simulation were performed using identical backup material. The influences of backup material height and thickness on burr sizes and burr profiles were characterized. The experimental results and simulated analyses indicated that effective burr control can be achieved using appropriate selection of backup material parameters. Furthermore, the cutting forces at steady state were found to be the same with different backup material heights and thicknesses. Therefore, the proposed technique will have a wide range of application prospects saving time and cost of deburring. This may bring remarkable economical and societal benefits.

Analysis of cutting force is important in research and development of metal cutting process and in designing cutting tools. This paper reports the theoretical computational formulae for cutting force for cylindrical turning using novel restricted contact tools that have inconstant tool/chip restricted contact length. These formulae are based on the minimum energy principle. The results of extensive cutting tests show that the derived theoretical computational formulae can predict the cutting force, especially the main cutting force, with reasonable accuracy. The novel RC tools-type II and type III can reduce cutting force as well as the conventional RC tools-type I. In addition, they can also effectively control the direction of chip curling, and type III RC tools may have a longer tool life due to the high strength of its cutting edge and the possibility of liquid coolant approaching the cutting zone. Finite element models have been developed to study the cutting force, and the results indicate that the main cutting force can be accurately predicted, while there are some inaccuracies for the feed force and thrust force because of the simplifications adopted during modeling.

With switch technology evolving from the program-controlled to soft-switch, and IMS technology, the power switch network faces technology selection. Through an investigation and analysis into the administrative switch network of the State Grid, and study the migration and evolution technologies in depth, consider the characteristics of electric communication network, this paper presents an evolution program for users and switch equipment transfer from existing administrative switch network to the IMS network. It provides a reference for the evolution of the SGCC administrative switch network.

Due to the numbers of transformer, the closing angle and other reasons, the inrush current performed intricately, which usually made the protection miss operation. Therefore, reliability and stability in protection of transformer is important task in distribution system. In this paper, an efficient method for detection of inrush current is presented, which is based on the attenuation factor of current fundamental, and the attenuation factor is calculated by the Prony algorithm, which could obtain the amplitude and the phase too. Finally, results in all cases show the reliability and feasibility of this method used a large number of dates which are from PSCAD simulation and actual scene.

IEC 61850 adopts object-oriented modeling techniques to model business functions of the substation, and defines substation configuration description object model by Substation Configuration description Language (SCL). SCL which is based on XML Schema cannot description the knowledge semantic and achieve substation knowledge exchanging of substation automation system. in this article, knowledge semantic of substation was analyzed and modeled based on ontology technology, including the relationships and constrains of substation knowledge semantic. By extending the label definition of SCL, the semantic exchange model is proposed and description ability of SCL is improved.