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To investigate the effects of Ginkgo biloba extract (GbE) on the activities of energy metabolism enzymes and contraction capacity of diaphragm from type 2 diabetic rats. Forty SD mile rats were randomly divided into normal control group (n=10) and model group (n=30). Type 2 diabetes models were induced by feeding with high-sucrose-high-fat diet and intraperitoneal injecting 25mg/kg streptozotocin. 20 successful models were rearranged to two groups: diabetic group and GbE treatment group, 10 rats in each. Then the saline and 8mg·kg-1·d-1 of GbE were respectively intraperitoneal injected, once a day continuously for 8 weeks. Then diaphragm contractility was assessed using Peak twitch tension (Pt), Maximum tetanic tension (P0) and fatigue index (FI) in vitro diaphragm strip preparations. Cytochrome oxidase (CCO), lactate dehydrogenase (LDH) and succinate dehydrogenase (SDH) in diaphragm were detected and the varieties of diaphragm ultrastructure were observed. Compared with control group, Pt, P0 and FI in diabetic group decreased significantly (P < 0.01); the activity of CCO, LDH and SDH in the tissues was obviously reduced than those in control group (P < 0.01). The ultrastructure in diabetic group under electron microscope indicated that diaphragm mitochondrions swelled and degenerated. The above changes were inhibited by GbE. GbE can enhance contraction capacity of diaphragm from type 2 diabetic rats by increasing the aerobic oxidation capacity, glycolytic capacity and the function of respiratory chain.

Type 2 diabetes was induced by feeding with high-sucrose-high-fat diet and injecting 25mg/kg streptozotocin. Rats were randomly divided into three groups: control, diabetic, diabetic simultaneously injected ip with Ginkgo biloba extract (EGb) for 8 wk. The treatment of EGb attenuated the development of hyperglycemia and hyperinsulinemia in type 2 diabetic rats. The serum levels of cholesterol, triglyceride as well as the activities of alanine aminotransferase, aspartate aminotransferase were significantly decreases in EGb-treated rats. The level of malondialdehyde were significantly increased in diabetic rats and decreased after EGb administration. Moreover, EGb markedly increased the activities of superoxide dismutase, catalase and glutathione peroxidase in liver. The results indicate that EGb has a protective effect on liver of type 2 diabetic rats, which may be related to decreases the accumulation of cholesterol, triglyceride in liver and its antioxidant property.

Improving the reliability of linear motor is one of the best ways to improve its quality and performances. The core in reliability test is to simulate the dynamic loading as real operating condition. In this paper, a common loading model, which can reflect various operating conditions of linear motor, is proposed. Then a set of dynamic loading method for reproducing the operating conditions is put forward. This method completes dynamic loading against linear motor simutaneously in its moving and non-moving directions using servo control contact method and magnetic non-contact method, respectively. This research provides not only a set of feasible method for linear motor reliability test in lab, but also a prerequisity for studying linear motor reliability further.

By analyzing the structure features and tool changing process of a large-scale national Automatic Tool Changer (ATC) with a chain-type tool magazine, a chain-type tool magazine reliability test bench is designed with a new fault detection system, where a new failure data collecting method is applied for taking failure data statistics and reliability analysis. This set of fault detecting and reliability analyzing system not only provides a way for ATC to predict system faults, but also creates good conditions for further ATC reliability research.

The purpose of this paper is to present a novel device for measuring draw and plug forces, which is composed chiefly of a pull stud, a top modified tool shank, a middle modified tool shank, a down modified tool shank, and an end cover. The modified tool shank structure is proposed, and the working principle of the device for measuring draw and plug forces is demonstrated. Also, the data conversion and memory module and the circuit principle are investigated.

In order to accurately emulate the operation conditions of high-speed motorized spindle in the reliability experiment, a dynamic loading system is proposed. This system allows simultaneously loading torque, radial and axial force against the spindle. The torque load is carried out by the electric dynamometer; the non-contact vibration exciter completes the radial load; the axial load is carried out by a self-made electromagnet. Moreover, this system also can detect out the basic features and failure data of the motorized spindle during the loading. And these sampling data provide a quantitative elevation for its reliability analysis. This paper presents a simple solution to the high-speed motorized spindle reliability research where the loading experiment is designed with the spindle whose maximum rotational speed is 18000rpm.

For the PWR power plant in service, the lifetime of RPV is mainly determined by fast neutron (E>0.1MeV and E>1.0MeV) fluence. A new Low-Leakage Core Loading (LLCL) pattern is considered to prolong the lifetime of RPV to 60 years for Daya Bay nuclear power plant. Fast neutron (E>0.1MeV and E>1.0MeV) flux inserted to Reactor Pressure Vessel (RPV) under LLCL pattern is calculate by MCNP and compared with that under Long-Short Alternating Core Loading (LSACL) pattern. The results show that fast neutron fluence over inner surface of RPV under LLCL pattern decrease 28.50% (E>1.0MeV) and 28.22% (E>0.1MeV) compared with LSACL pattern and it is feasible expand the life of LWR-RPV to 60 years by LLCL pattern.

Various intensity heat fluxes firefighters encountered will produce thermal stress on skin, resulting in thermal pain and tissue damage. In this paper, a new approach to evaluate thermal stress under flashover with short duration was carried out based on plain-stress theory. Instant heat flux under fabric was calculated so as to determine temperature and thermal stress distribution. The results obtained were as follows: temperature increased slightly at initial stage and then sharply increased linearly, moreover, temperature was much higher when sensor directly contacted with specimen, comparing with that of 6mm air gap; heat flux under fabric quickly reached its maximum, and higher heat flux was observed as no air gap generated; thermal stress rapidly increased and then gradually decreased, moreover, higher thermal stress produced without air gap. The newly proposed method could well distinct heat transfer performance of fabric under different conditions, which might provide helpful guideline to performance evaluation of thermal protective clothing.

A new type of low-heat accumulation asphalt concrete material has been made to reduce urban surface temperature and to ease the urban heat island effect. The test has investigated the temperature reduction performance and pavement performance, established a non-gray model of the atmospheric temperature field, and evaluated its effect on the urban thermal environment. The results show that compare specimens mixed with infrared powder with normal ones, the higher the infrared powder content, the lower the surface temperature, but the cooling rate decreases; the properties of high-temperature stability, low-temperature stability and water stability are improved; under the same temperature and humidity conditions, the surface layer temperature of the former pavement is lower generally; under the same radiation conditions, the surface equilibrium temperature of the former ones is 8.12K lower, which can reduce the near-earth atmospheric temperature and ease the urban heat island effect.

In peer-to-peer (P2P) networks, nodes are quite different from each other in many aspects, such as sharing resources, online time and bandwidth. Some approaches have been introduced to take advantage of the query forwarding and answering heterogeneity such that the high bandwidth and query answering capability of nodes can be fully utilized to improve the system performance. In this paper, we suggest using the online time heterogeneity to improve the search efficiency of P2P networks. In our proposed Differentiated Index (Diff-Index) algorithm, the nodes with long online time will have higher priority to be queried. Because the online time is quite different among nodes, much search traffic can be saved by querying only a small portion of a network. The query success rate can be kept high because the nodes sharing a great amount of resources tend to have long online time. Our simulation results show that the Diff-Index algorithm can save 66 percent of search traffic.