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In this report, silver nanowires (NWs) with different sizes have been obtained by using the poly process synthesis method. As-synthesized samples 1, 2, and 3 with high purity and different sizes have been obtained by changing the amount and kind of inorganic agent in the synthesis procedure. Three samples have been characterized by the scanning electron microscopy (SEM) and powder X-ray diffraction (PXRD). The SEM images of Ag NW 1 (74 nm in diameter, 20–30 μm in length), Ag NW 2 with (60 nm in diameter, 30–40 μm in length), and Ag NWs 3 with (46 nm in diameter, 30–40 μm in length) are obtained. The PXRD results for Ag NWs 1–3 show four typical diffraction peaks at 38.2°, 44.5°, 64.5°, and 77.4°, matching the face-centered cubic lattice for Ag substance and confirming the purity of the Ag NWs sample. In addition, the relative expression of the PTEN and mTOR was determined with real-time RT-PCR at the mRNA level. The content of inflammatory cytokines during stoke was measured with indicated ELISA assay.

An iterative polynomial fitting method is proposed for the estimate of the baseline of the X-ray fluorescence spectrum signal. The new method generates automatic thresholds by comparing the X-ray fluorescence spectrum signal with the calculated signal from polynomial fitting in the iterative processes. The signal peaks are cut out consecutively in the iterative processes so the polynomial fitting will finally give a good estimation of the baseline. Simulated data and real data from the soil analysis spectrum are used to demonstrate the feasibility of the proposed method.

Objective To explore effects of resuscitation with different kinds of fluid on liver oxygen free radical in rats with severe hemorrhagic shock. Methods Sixty SD Rats were randomly divided into 5 groups (n=12): control group (C), shock alone group (SA), lactated Ringer's solution (LR)-treatment group, hydroxyethyl starch (HES)-treatment group, 7.2% hypertonic saline-6% HES (HSH)-treated group. According to Wigger's method, the rat model of severe hemorrhagic shock was reproduced. The mean arterial pressure (MAP) was monitored in all the 5 groups. The ALT and AST level in venous blood were determined before shock (Tb), 1h after shock (Ts) and 4h after resuscitation (Td) respectively. In SA group, the rats were sacrificed and the livers were collected at Ts. The rats were resuscitated with LR (3 times the volume of shed blood), HES (1 time the volume of shed blood) and HSH (6ml/kg) in LR, HES and HSH group respectively. The rats in groups C, LR, HES and HSH were sacrificed at Td to obtain the liver tissues. The expression of TNF-α, NF-κB protein, MDA and SOD activities were determined by immunohistochemistry (SP) and chromatometry. The iNOS content was detected by ELISA. The livers were also observed under light microscope and electron microscope for pathological changes. Results Compared with group C, the AST and ALT levels in other groups were significantly higher, the expressions of NF-κB, iNOS and MDA in liver significantly increased, while SOD activity significantly decreased (P＜0.05). The signs of injury were remarkable. The content of cytokines was significantly increased in blood in 3 fluid resuscitation groups compared with group SA (P＜0.05), and signs of tissue injury were also significant. In 3 fluid resuscitation groups, the increase in cytokines was most remarkable in group LR (P＜0.05), and liver tissue injury was also most remarkable, while the cytokine levels were lower (P＜0.05) and pathological changes were also milder in HSH group. Conclusions HSH resuscitation produces loss liver injury after severe hemorrhagic shock by decreasing cytokine production and reducing oxygen free radical-mediated lipid peroxidation.

To satisfy more and more complicated requirements on information recording, processing, exchange etc. in newly developed intelligent satellites, a distributed storage system is designed based on SpaceWire network in satellite platform. In this distributed storage system, a SpaceWire router unit serving as the core device of star network connects several nodes, including onboard computers, namely, satellite management unit (SMU), data interface units (DIU) and other nodes like attitude and orbit sensors, space environment monitor instruments and payload controllers, etc. A certain number of standard flash memory modules are separately incorporated into SMU and DIUs to provide comprehensive data recording and exchange service for all nodes in the network. All memory modules are centrally controlled by SMU software to store authorized data in specific type files and retrieve data according to policies set by remote memory access protocol commands. Memory modules that can run in parallel in the distributed storage system produce very high data throughput, which boosts satellite platform capability to a great extent. Backup mechanism among memory modules is deployed and any module can be replaced by others when it meets failure, this makes the storage system robust and reliable. Testing and verification work performed on the distributed storage system shows that the system works quite well and also reveals its attractive effect on improving satellite platform efficiency.

Objective To investigate the effects of pentoxifylline(PTX) on oxygen free radicals in liver as a result of ischemia-reperfusion in rats with severe hemorrhagic shock.Method Forty-eight SD rats were randomly divided into four groups(12 each): control group(C),no resuscitation group(NR),Ringer lactate solution(LR)-treatment group(LR),and LR combined PTX(25mg/kg) group(LRPTX).The rat model of severe hemorrhagic shock was established according to Wiggers method.Blood samples were collected at Ts(before shock) and Td(before sacrifice) for determination of AST and ALT.The rats were sacrificed and the livers were obtained for the determination of the activity of SOD,the contents of MDA and iNOS,and the expression of NF-κB immediately after shock in NR group and 4 hours after resuscitation in C,LR and LRPTX group.The pathological changes in the livers were observed with light microscope and electron microscope.Results Compared with C group,the AST and ALT levels in venous blood,the contents of MDA and iNOS,and the expression of NF-κB in liver were all significantly increased in NR,LR and LRPTX groups at Td time point,while the activity of SOD significantly decreased(P < 0.05).There also showed signs of severe injury to the liver.Compared with LR group,the AST and ALT levels in venous blood,the contents of MDA and iNOS,and the expression of NF-κB were significantly decreased in LRPTX group,while the activity of SOD significantly increased(P < 0.05).Pathologic changes of injury to the liver were significantly milder.Conclusion PTX can protect liver against ischemia-reperfusion injury by decreasing iNOS production and NF-κB activation,inhibiting the generation of oxygen free radical and enhancing the activity of SOD.