ISSN 0253-2778

CN 34-1054/N

2010 Vol. 40, No. 4

Display Method:
Enhanced growth of the H5N1 influenza vaccine strain NIBRG-14 by the neuraminidases packaging signal sequence of A/Puerto Rico/8/34
ZHENG Wei, PAN Weiqi, YANG Huaqiang, LI Ting, ZHANG Beiwu, LI Feng, CHEN Ling
2010, 40(4): 331-338. doi: 10.3969/j.issn.0253-2778.2010.04.001
Abstract:
NIBRG-14 is one of the H5N1 candidate vaccine viruses developed using “6+2” approach with the hemagglutinin (HA) and neuraminidase (NA) genes derived from A/Vietnam/1194/2004(H5N1, VN1194) and the remaining six internal segments from A/Puerto Rico/8/34(H1N1, PR8). However, NIBRG-14 was reported to yield low amounts of HA antigen. This study found that the NA vRNA of VN1194 is poorly packaged (38%~68%) into the recombinant viruses with a backbone of PR8 genes, causing the formation of defective virions without the NA vRNA in viral genome. Using recombinant DNA techniques, we constructed a chimeric NA gene with the coding region of VN1194 NA flanked by the packaging signal sequence (vRNA 3′end 41bp, 5′end 67bp) of PR8 NA. The packaging of NA vRNA is completely restored in the recombinant viruses with the chimeric NA gene. Moreover, the recombinant viruses contained the chimeric NA gene replicate better in chicken embroynated eggs than recombinant viruses with wild type NA gene of VN1194, as indicated by a 10-fold increase in virus titer and 27-fold increase in HA antigen content. These findings suggest a novel strategy to improve the in ovo growth and increase the available dose of NIBRG-14 in vaccine manufacture.
Studies on autophagy induced by nano-C70, nano-C60Cl6 and nano-C60Ph6
SUN Kejing, ZHENG Fang, WEN Longping
2010, 40(4): 339-345. doi: 10.3969/j.issn.0253-2778.2010.04.002
Abstract:
In order to further study the autophagy induced by fullerene family and its derivatives, nano-C70, C60Cl6 and C60Ph6 were selectively investigated by means of fluorescence microscope, transmission electron microscope and western blot. The results show that, nano-C70, C60Cl6 and C60Ph6 can form crystal structures in water and induce HeLa cells into autophagy process, which indicates that fullerene family and its derivatives might play a new role in the biomedical field.
Leukocyte-specific protein 1 inhibits Bortezomib induced apoptosis in multiple myeloma cells
FANG Yinghui, REN Zijia, MA JIajia, GUO Yugang, ZHAO Ying, XU Lu, FANG Fang, WANG Yongqing, XIAO Weihua
2010, 40(4): 346-352. doi: 10.3969/j.issn.0253-2778.2010.04.003
Abstract:
To investigate the roles of anti-apoptosis by leukocyte-specific protein 1 (LSP1) in Multiple Myeloma cells (MM), RT-PCR and immunoblotting were used to assess the gene expression in MM cell lines, IM9 and KAS6. Plasmids containing either sh-RNA targeting LSP1 or full-length cDNA coding for human LSP1 were constructed and transfected into IM9 and KAS6 cells, respectively. Cell apoptosis rate induced by Bortezomib was measured by PI/Annexin V staining and FACS assay. The results shows that LSP1 is highly expressed in IM9 cells but undetectable in KAS6 cells and that is closely correlated with their abilities of anti Bortezomib-induced apoptosis. Knockdown LSP1 in IM9 cell leads to significant reduction of anti Bortezomib-induced apoptosis compared with its parent control cells. By contrast, overexpression of LSP1 in KAS6 cells remarkably increases its anti-Bortezomib ability compared with control KAS6 cells. RT-PCR shows that p53 is suppressed and Bcl-xL is up-regulated by LSP1 in MM cells. In conclusion, LSP1 inhibites Bortezomib-induced apoptosis in multiple myelomas by suppressing multiple pro-apoptosis genes.
Molecular dynamic simulation of interactions between SWNTs and functional groups of proteins
YANG Pengjun, JIN Bangkun, ZHU Pingping, YANG Haiyang
2010, 40(4): 353-357. doi: 10.3969/j.issn.0253-2778.2010.04.004
Abstract:
The interactions between SWNTs (single-walled carbon nanotubes) and functionalized SAMs (self-assembled monolayers) in aqueous solution were simulated through the molecular dynamic method. The SAMs were functionalized by the functional groups of proteins. The simulation results showed that the interaction energy between SWNTs and the charged SAMs are zero because of the solvent effect of water molecules. The SWNTs have affinity with the uncharged SAMs, while the van der Waals interaction gives the dominant effect to the interaction energy. The analysis of the distance of the mass center also proved that the types and ionization states of the functional groups had a strong influence on the interactions between SWNTs and SAMs. The effective interaction distance between atoms of proteins and SWNTs was also validated.
Catalytic combustion of methane over double perovskite Sr2Fe1-xMgxMoO6 mixed oxides
WANG Zhenghong, FENG Shaojie, YANG Pinghua
2010, 40(4): 358-362. doi: 10.3969/j.issn.0253-2778.2010.04.005
Abstract:
A series of double perovskite mixed oxide catalysts nominal Sr2Fe1-xMgxMoO6 was prepared with the sol-gel method and the properties of as-synthesized powders were characterized by XRD, BET, XPS, and TG. The catalytic activity of the Sr2Fe1-xMgxMoO6 for catalytic combustion of methane was tested in a pure oxygen atmosphere without dilute gas. The TG curves exhibit a typical two weight-loss processes similar to that of perovskite oxides. The results reveal that the catalytic activity of Sr2Fe1-xMgxMoO6 is affected by Fe/Mg ratio distinctly. It is suggested that substitution Fe ion with Mg results in the order of structure and the decrease of oxygen vacancy concentration on the surface, which is disadvantageous to the catalysis activity of methane combustion.
Numerical study on a dual-functional building integrated solar collector
LUO Chenglong, JI Jie, SUN Wei, HE Wei, PEI Gang
2010, 40(4): 363-368. doi: 10.3969/j.issn.0253-2778.2010.04.006
Abstract:
A novel system of dual-functional building integrated solar collector is proposed. The system can run in two independent modes: passive space heating in cold days and solar water heating in hot days. Dynamic numerical models have been established to investigate the performance of the system in the two operating modes. Results show that when the system works in the space heating mode, the indoor air temperature reaches the maximum value of 274 ℃, with the maximum value of ambient temperature being only 28 ℃; when working in the water heating mode under given simulation conditions, the thermal efficiency of the collector is 548%, with the solar heat gains being 432 MJ/m2.
Researches on discharge characteristics of needle-to-plate CDBD
HE Xianjun, ZHOU Zhipeng, NI Weijie, YU Xi, XIA Weidong
2010, 40(4): 369-373. doi: 10.3969/j.issn.0253-2778.2010.04.007
Abstract:
The characteristics of single needle-to-plane corona-dielectric barrier discharge (needle-to-plate CDBD) with glass fiber as packing dielectric were investigated. Discharge voltage and current waveforms were measured and the discharge power was calculated. The discharge currents with and without glass fiber filled between electrodes were compared, and the relationships between discharge power and gas gap distance, capacitive current, discharge voltage were analyzed. The influence of glass fiber as packing dielectric on the characteristics of single needle-to-plane corona-dielectric barrier discharge were studied experimentally. Comparing the corona-dielectric discharges observed in air and in a medium filled with glass fiber as packing dielectric, it was found that: ① the latter has less onset discharge voltage and greater discharge power; ② continuous discharge current of the latter decreases obviously while discharge pulse number and their current amplitude increase significantly; ③ unlike the more continuous currents in the former, there is more pulse discharge during negative voltage on the needle electrode in the latter.
Startup and combustible limit of porous medium built-in Swiss-roll burner
HE Xianzhao, XIE Hongzhan, LI Yongling, MA Peiyong, LIN Qizhao
2010, 40(4): 374-379. doi: 10.3969/j.issn.0253-2778.2010.04.008
Abstract:
Porous medium was added to the central area of a conventional scale Swiss-roll combustor, and an experiment research was conducted. The starting process of the combustor under different conditions and its lean flammability characteristics were analyzed by monitoring the combustors temperature development and the transformation of the combustion products. The experimental results show that, ignition at the central area takes a shorter time for complete combustion compared with that at the entering point and the temperature distribution of the porous media is more uniform; the porous media properties and that the pre-mixed gas flow rate have great influence on the startup characteristics. Furthermore, when the temperature of the combustor center is between 950 K and 1 200 K, it can burn 13% natural gas/air premixed gas, indicating that porous medium built-in Swiss-roll combustor can expand the fuels lean flammability, and is well applicable to low-calorific gases.
Study on flame pulsation of pool fires in closed compartments
LI Changhai, WU Yingchun, LU Shouxiang, CHEN Bin, HU Jing, YUAN Man, ZHOU Yang
2010, 40(4): 380-386. doi: 10.3969/j.issn.0253-2778.2010.04.009
Abstract:
A series of experiments on heptane pool fires were conducted in a closed compartment without vents with the inner dimensions of 1 m(L)×1 m(W)×075 m(H), focusing on flame pulsation characteristics. Different pools with the diameters of 0100, 0141, 0200 and 0300 m were investigated. Based on the fact that pulsation frequency of flame bottom area equals that of flame height, a method using flame bottom area was proposed to determine flame pulsation frequency and applied to pool fires in closed compartments with ceiling jet flames. The results show that the variation of flame pulsation frequency is small, and the flame pulsation frequency is smaller than those predicted by empirical equations developed for burnings in free atmosphere while it fits well with the scaling relationship St=026 Fr-0.532, and the expression of f=133D-0.5 is appropriate in describing the relationship between the flame pulsation frequency and pool diameter.
Reconstruction of a bus fire based on numerical simulation
BI Kun, QIU Rong, JIANG Yong, ZHENG Jingchuan
2010, 40(4): 387-394. doi: 10.3969/j.issn.0253-2778.2010.04.010
Abstract:
Fire scene simulation using fire dynamics simulator(FDS) may provide evidence for fire investigation. Numerical simulation of the bus fire may recur the fire scene, reconstruct fire processes and explain fire development, smoke movement and deaths by describing the fire source, configuration of the bus and property of fuel. Based on the descriptions of evacuees and rescuers, and the combustion evidence of the scene, reconstruction simulation was performed by adopting parallel operation. Multi-parameter measurement, including heat release rate(HRR), temperature field, soot density and species concentration, was accomplished. The simulation results, compared with the fire site reconnaissance results, demonstrated good prediction of fire development and smoke movement and explained the causes of deaths. Furnishing a good foundation for further research into whole fire reconstruction and demonstrate the application of fire simulation to actual fire scene investigation.
Coupling control of actuators for MEMS-based deformable mirror
LIU Yong, XU Xiaohui, LI Baoqing, ZHANG Jinhong, CHU Jiaru
2010, 40(4): 395-399. doi: 10.3969/j.issn.0253-2778.2010.04.011
Abstract:
Based on the correction of the residual error of wave-front correction, the relationship between the coupling of actuators and correction capability of MEMS-based deformable mirror (DM) is analyzed. When a single actuator of the continuous surface DM works, it creates a displacement at the other actuators, which is described using coupling coefficient (cc). For a MEMS-based DM with a 10×10 actuator array, with the distance between two adjacent actuators (b) being 3 mm, correcting the first 20 Zernike modes, the best coupling coefficient is 10%. Different distances between two adjacent actuators (b) correspond to different correction capabilities and different coupling coefficients. Corresponding to b of 2, 25, 3, 35, and 4 mm, the best coupling coefficient of the DM is 12%, 11%, 10%, 9%, and 8%, respectively.
The patterning of microplasma reactor electrode using sputtering image reversal lift-off process
ZHANG Qiuping, WEN Li, XIANG Weiwei, WANG Hai, CHU Jiaru
2010, 40(4): 400-405. doi: 10.3969/j.issn.0253-2778.2010.04.012
Abstract:
The image reversal lift-off process, which is used to pattern the microplasma reactor electrode, is studied. Nickel film is deposited by sputtering and then formed on electrodes using lift-off process based on AR-U4030 photoresist. The effects of reversal bake and develop time on the pattern quality of the photoresist are analysed. Furthermore, the influence of the sputtering power, time and ultrasonic cleaning on the lift-off process are investigated. The thickness of Ni obtained here achieved more than 200 nm and the image resolution is higher than 2 μm.Finally, the inverted square pyramid microplasma reactor is fabricated using this lift-off process, and the electrical characteristic of the reactor operating stably in SF6 is presented.
A study of the influencing factors of wireless sensor network beamforming
YOU Lan, LIU Falin
2010, 40(4): 406-411. doi: 10.3969/j.issn.0253-2778.2010.04.013
Abstract:
Wireless sensor networks (WSN) technology was combined with antenna array beamforming to realize WSNs long range communication. Instead of using isotropic antennas as reported in the literatures, all nodes in this paper were equipped with directional antennas for beamforming. The influence of sensor node failure and position error on the combined beam pattern was analyzed considering the antenna beam inclination. The nodes radiation power adjustment was studied to reduce the side lobe level effectively as the main lobe remained almost unchanged. To increase the networks coverage area, node distance can be extended within a certain range which is constrained by the antenna beam pattern.
Adaptive subcarrier allocation for multiuser MIMO-OFDM systems based on imperfect feedback
SUN Qunlong, WEI Guo
2010, 40(4): 412-418. doi: 10.3969/j.issn.0253-2778.2010.04.014
Abstract:
An adaptive subcarrier allocation algorithm based on imperfect feedback was proposed for multiuser MIMO-OFDM systems with VBLAST architecture. Not only the feedback channel information, but also the feedback quality were considered in the algorithm. The definitions of confidence coefficient and equivalent variance were introduced to indicate the feedback quality, and the closed expressions were deduced in actual environments considering both feedback delay and feedback error. Simulation results show that the proposed algorithm can improve system performance in various imperfect feedback scenarios.
Selective cooperative communication based on power optimal allocation
ZHANG Chao, LIAO Xiaoguang, WANG Weidong, WEI Guo
2010, 40(4): 419-424. doi: 10.3969/j.issn.0253-2778.2010.04.015
Abstract:
Cooperative communication is considered as a power-efficient technology for resource-constraint wireless networks. However, its gains often come at a price in terms of extra power consumption for relay running and relaying processing. A new selective cooperative scheme was proposed to satisfy an overall performance requirement so that cooperation is only invoked when necessary. Optimal power allocations under overall symbol-error-rate (SER) constraint and maximum power limit were derived for cooperative schemes. Taking into account extra power, the scheme with minimum overall power was adopted for a source-destination pair. Simulation results show that the proposed schemes are more power-efficient than the conventional cooperative scheme.
A multi-user interactive genetic algorithm and its application in group design
YOU Haifeng, WANG Xiwei, XU Xiang, WANG Xufa
2010, 40(4): 425-430. doi: 10.3969/j.issn.0253-2778.2010.04.016
Abstract:
General interactive genetic algorithms allow only one user to participate in evaluation for candidate solutions, so their results can only reflect one users preference. But we should try to meet as many users needs as possible when designing products. To solve this problem, a multi-user interactive genetic algorithm (MUIGA) applicable for group design was proposed. And the detailed design of the three key modules-population initialization module, single-population module and multi-population module was given. Finally, the proposed algorithm and the general single-user interactive genetic algorithm were applied to a fashion design system, respectively. The experimental results were compared to validate the feasibility of MUIGA in group design.
A resource pricing method based on game theory for service overlay networks
ZHENG Mingchun, YANG Shoubao, LIU Xiyu
2010, 40(4): 431-438. doi: 10.3969/j.issn.0253-2778.2010.04.017
Abstract:
Service overlay network (SON) is a virtual service network built on underlying network. It purchases resource from the underlying network and provides cross-domain and QoS sensitive value-added services to gain profits. Resource pricing is thus a key problem for the SON operator. This paper is devoted to the study of the problem of resource pricing with elastic demand based on game theory. After giving a SON architecture, the pricing problem was formulated in a bilevel programming model taking the effect of congestion and QoS on objective into consideration. The upper level model aims to maximize the difference between the revenues and the cost of the whole SON system, while the lower level model is a Wardrop user equilibrium model with elastic demand. A heuristic solution algorithm based on the trial-and-error procedure and difference sensitivity analysis method is designed for the proposed bilevel programming model when precise link congestion metric function and demand function are unknown. Numerical examples are also performed to illustrate the convergence and effectiveness of the bilevel programming model.
Great achievements for the general circulation over Eastern Asia and the new chapters of global change —The Impressions form “Selected Papers of Ye Duzheng”
CHEN Yuejuan
2010, 40(4): 439-440. doi: 10.3969/j.issn.0253-2778.2010.05.000
Abstract: