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Air pollution is one of the most serious environment pollution. 8 typical landscape plants, in Suzhou City, were selected to quantitative study their dust-capturing capacities, and the morphological traits of their leaves were observed under a SEM (scanning electron microscope). The paper showed that there were great differences in the dust-capturing capability of garden trees, and the dust-capturing capacities of garden trees in different seasons were in the order of May > August > November; the leaves of Cinnamomum camphora (L.) Pres, Camellia japonica L. and Euonymus japonicus Thunb. var. Ovatus Aureus had smooth surfaces or tubercles, whose dust-capturing capacities were poor, while the leaf of Loropetalum chinense(R.Br.) Oliv.Var. rubrum Yieh had many wrinkled form of cuticle, deep grooves, trichomes and high stomata desity which were favor of dust-retained, thus its dust- capturing capacity was stronger. The results can be seen as a possibility of select suitable species for urban environment.

The error distribution of a machined NURBS surface is complex to describe since the machined surface isnt that easy to obtain. A new method for machined NURBS surface description based on inspection database of on-machine probing is presented. The main idea is to approximate the machined surface using the inspection data and the basis functions of the nominal NURBS surface and to get the error distribution of the surface. A virtual part with a NURBS surface is presented and its error caused by the interaction of the machine-tool-workpiece is obtained using the FEA method at the inspection points. A machined NURBS surface is achieved and the error distribution of the surface is expressed. This method provides a new way in error compensation and it will improve the machining accuracy of a NURBS surface.

Great efforts have been made to improve the accuracy of NC machine tools, within which thermal error compensation is one of the most efficient ways. A new thermal error compensation instrument which is based on thermal modal analysis for NC machine tools is introduced in this paper. OMRONsCJ2M-CPU11 is used as microcontroller, and SAILING TECHNOLOGYs STA-A08 temperature measuring modules as temperature transmitter. Through hardware and software design, high precision and stability can be achieved. By measuring several key points temperature and making use of a thermal error compensation theory, real-time thermal error compensation can be output to the machine tool, thus thermal error can be reduced.

Thermoelectric energy harvesting is emerging as a promising alternative energy source to drive wireless sensors in mechanical, civil, and aerospace engineering systems. Typically, the waste heat from spindle units of machine tools creates obvious potential for thermoelectric generation. The structure of heat sinks on a thermoelectric generator has a great effect on the output voltage of the thermoelectric generator due to the temperature difference between hot and cold sides induced by heat transfer, so several typical structures of heat sinks are studied under different rotation speed of the spindle. According to the simulation study, the thermal resistance of heat sinks was presented. In the experiment, the output voltages of a thermoelectric generator were measured under different rotation speed with different structures of heat sinks. Experiment and simulation shows that the two pipes structure of the heat sink can help the generator to produce more power.

An error mapping modeling and identification technology for the circular path test of NC machine tools is proposed. First, geometric error modeling of the NC machine tool was established and the theory of the laser measurement method was introduced. Then through further analyzing the influence of the geometric errors to circular path deviations, the error items were identified, such as the displacement errors, backlashes and squareness errors. Finally measurement and compensation experiment of circular path was conducted. The experimental results show that the geometric error modeling is feasible, and the measurement method can be set up easily and rapidly, even can be used to measure smaller radius circular path under a high feed rate condition. After compensation, the accuracy of the circular path of the machine tool is improved by 50.88%.

Rotating spindle is the main heat source of machine tool. However, it is hard for the traditional wired sensors to get access to the temperature value in rotating environment. This is one of the largest challenges that the researchers will encounter in machine thermal analysis and machine's state monitoring, and it limits the accuracy of the machine thermal analysis and state monitoring. Recently some researcher begins to adopt wireless communication technologies into the measurement in rotating environment, which would overcome the weakness of wired sensors. This paper first describes the superiors of the popular wireless technology ZigBee. And then presents the design of a wireless temperature measurement system based on ZigBee. In the Last, the system is implemented into a wireless temperature measuring experiment. The result of the experiment proved the stability of the wireless temperature measuring system, and shows the clear advantage of wireless sensors compared with wired sensor in rotating environment.

This research presents a design of a thermal deformation errors compensation system for CNC machine tools which can compensate thermal deformation of Z-axis during the working time. The thermal deformation errors compensation system includes three instruments: displacement tester, temperature tester and thermal errors compensator. Displacement and temperature testers have been designed in the early researches, and the thermal errors compensator is designed in this research. The compensation process includes two parts, modeling part and compensation part. Modeling part focuses on making a model of thermal deformation, and compensation part focuses on using the model to compensate the thermal deformation of Z-axis during the working time.

Wireless sensors are increasingly adopted in mechanical systems to acquire and wirelessly transmit sensed information for machine condition monitoring. For wireless sensors on spindle, the reliability of the sensors system at high rotary speed is the key factor to guarantee the validity of monitoring. How to identify sensor failure accurately and timely is essential to enhance reliability of monitoring system. To address this issue, a novel method based on the BNs was presented to distinguish sensor failure from other transmission errors. The method described causal relationships of factors inducing sensor failure by graph theory and deduced sensor failure by Bayesian statistical techniques. Experiments carried on NC machining center prove the validity of this approach.

Considering the development of cooperative design and internet-based manufacturing and in order to manage the manufacturing process more efficiently, a unit of remote intelligent fault-diagnosis based on Bayesian Networks was designed and a software based on internet was realized. The establishment of such system will enable efficient cooperation between CNC machine tools and users as well as maintainers.

With the development of the CNC precision machining and the ultra-precision machining, machine tools error issue has became the most active research topics and concerned by more and more experts. In this paper, a rapid simulation software platform based on multi-body system theory and Matlab software for measurement and analysis geometric errors of CNC machine tool is presented, which includes the generation of simulated measurement data, data processing, error separation and error compensation etc. To verify the feasibility of the developed software, the sequential step diagonal vector measurement method has been analyzed. The experimental results show that after error compensation the machine performance is improved by 39%. It demonstrates that the sequential step diagonal vector measurement method could significantly improve the machine accuracy and the developed software platform is reliable. This platform is not only effective for step diagonal vector measurement method, but also can be applied to other measurements. Therefore, the software platform provides a fast, reliable and objective tool for machine error measurement and analysis.

In 2006, Tahyna virus was isolated from Culex spp. mosquitoes collected in Xinjiang, People’s Republic of China. In 2007, to determine whether this virus was infecting humans, we tested serum from febrile patients. We found immunoglobulin (Ig) M and IgG against the virus, which suggests human infection in this region.

To describe the modular structure of numerical control (NC) system and deal with the problem of interference between modules in software reliability analysis, a module dependency graph (MDG) was presented and a scenario-based scheme was proposed. MDG describes reliability of module in different application environment, module dependency and structure of software with establishing maps among modules, execution scenarios and reliability. According to the information shown in MDG, an algorithm based on the idea of traversing directed graph in graph theory was proposed. The algorithm calculates the reliability of scenario with breadth-first principle. The reliability of system could be obtained from reliability and running frequency of scenario. The scheme eliminates the defects of the conventional methods which ignore module correlation. Case study proves the scheme could evaluate the reliability of NC software effectively.

To the Editor: West Nile virus (WNV) is a mosquito-borne flavivirus in the Japanese encephalitis serocomplex of the family Flaviviridae (1). It has been reported in Africa, Asia, Europe, Australia, and North America, and is recognized as the most globally widespread mosquito-borne flavivirus (2). Isolation of WNV has previously been attempted in China, Japan and South Korea; however, no virus has been isolated (3–5). We report isolation of WNVs from mosquitoes in Xinjiang Uyghur Autonomous Region in western China. We also provide evidence of WNV human infections confirmed by IgM ELISA and seroconversion by 90% plaque reduction neutralization tests of paired serum samples obtained from persons with febrile illness and viral encephalitis in 2011.

Using density functional theory (DFT), we have investigated the stability and electronic structure of lithium (Li) adsorbed in triplet form of (5.0) carbon nanotubes (CNTs) and (5.0) boron nitrogen nanotubes (BNNTs). We have mainly found that three (5.0) tubes are covalently connected. The triplet form is an energetically stable semiconductor. Li atom can be chemically adsorbed in the triplet form of nanotubes (NTs). Meanwhile, upon the adsorption of Li, the triplet form convert into metal. Hence, the triplet form can improve reactivity and sensitivity of NTs to Li significantly.

In 2006, the first Chinese Tahyna virus isolate (XJ0625) was obtained in Xinjiang province and human infection were found in the same region. In this study, cell culture, animal experiments, electron microscopy, immunofluorescence assay and cross neutralization tests were performed to see the cell susceptibility, animal pathogenicity, morphology and antigenic and other biological characteristics of XJ0625. In addition, molecular biology software was used to analyze the characteristics of molecular evolution. The results showed that BHK-21 cell line was susceptible to XJ0625 and the virus was lethal to suckling mice when injected by intracranial ways. Similar to the other Bunyavirus, Tahyna virus is spherical enveloped virus under electron microscopy. XJ0625 infected cells showed strong fluorescent signal and could be neutralized by immune asities fluid with immnity to protype Tahyna virus Bardos 92. The sequence of the S and M segments showed 91.8% and 81.9% homology with Bardos 92.

To investigate the effects of intrathecal escin and clonidine, used alone or in combination, in the treatment of neuropathic pain in rats and the possible mechanism.Ninety-six male SD rats weighing 250-300 g were chronically implanted with lumbar intrathecal catheters. One week later, the left L5 and L6 spinal nerve roots were ligated to establish the model of spinal nerve ligation neuropathic pain (SNL). The rats were then randomly divided into 16 groups (n=6), including the control (saline), escin, clonidine, escin+clonidine, and the antagonist groups. Mechanical withdrawal threshold was assessed before and at 5, 10, 20, 30, 40, 50 and 60 min after intrathecal administration was evaluated. The maximal possible effect (MPE) was calculated and the effect of the treatments on the neuropathic pain. Isobolographic analysis was performed to characterize any potential interactions between the drugs.MPE was significantly higher in escin group (20, 40 microg), clonidine group (2, 5, 10 microg) and escin+clonidine group [1/4, 1/2 (escin ED(50)+clonidine ED(50))] than in the saline group (P0.05). Intrathecal escin (5-40 microg) or clonidine (1-10 microg) alone dose-dependently alleviated neuropathic pain. Isobolographic analysis suggested a synergistic effect between escin and clonidine. Intrathecal pretreatment with yohimbine (20 microg) antagonized the effects of clonidine (P0.01) and attenuated the action of the combination treatment with escin and clonidine (P0.05).Intrathecal escin and clonidine alone can dose-dependently relieve neuropathic pain. Escin and clonidine produce a synergistic effect for pain relief, which may involve the actions of alpha(2) receptor and Ca(2+) channel.

To compare the effects of propofol target controlled infusion (TCI) and sevoflurane inhalational anesthesia on the hemodynamics and postoperative recovery in patients undergoing laparoscopic cholecystectomy.Sixty ASA IorII patients scheduled for laparoscopic cholecystectomy were randomized into propofol TCI group (group P) and sevoflurane inhalational anesthesia group (group S). In group P, TCI propofol was maintained after intubation until incision closure with the target concentration at 3 microg/ml. In group S, sevoflurane (end-tidal concentration of 2%) was maintained with oxygen flow rate of 2 L/min until incision closure. Fentanyl and vecuronium were intravenously infused according to the depth of anesthesia during the operation. MAP and HR were measured before anesthesia (T(1)), immediately after intubation (T(2)), at skin incision (T(3)), 10 min after pneumoperitoneum (T(4)) and immediately after completion of the operation (T(5)) respectively. Awake time, postoperative nausea and vomiting of the patients were observed after operation.There was significant difference in MAP and HR at T(4) between the two groups (P0.05), but not at T(1), T(2), T(3) and T(5) (P0.05). No significant difference was also found in the awake time between the two groups (P0.05). The incidence of PONV, however, was significantly lower in group P than in group S (P0.05).Propofol TCI and sevoflurane inhalational anesthesia are all effective in inducing good anesthetic effect, maintaining hemodynamic stability and ensuring rapid recovery, but propofol TCI causes lower incidence of PONV in operations such as laparoscopic cholecystectomy.

To evaluate the effects of acute normovolemic hemodilution (ANH) combined with controlled hypotension on reducing heterogeneous transfusion and safety during liver tumorectomy.Thirty patients undergoing elective liver tumorectomy were randomly divided into 3 groups (10 each), namely ANH group (group A), ANH combined with controlled hypotension group (group B) and control group (group C). All the patients were anesthetized via endotracheal intubation. Before the operation, ANH was performed in groups A and B after anesthesia induction, and controlled hypotension was initiated in group B during tumorectomy. Blood transfusion and fluid infusion were carried out routinely in group C. Hb and Hct were measured before operation, after ANH, and immediately, 1 day and 7 days after the operation. The difference in intraoperative blood loss and heterogeneous blood transfusion volume in the 3 groups was observed.In group A, heterogeneous blood transfusion was avoided in 6 cases and but given in the other cases for an average of 400 ml. In group C, every patient received heterogeneous blood transfusion (664.8-/+248.1 ml), but none of the patients received heterogeneous blood in group B. The difference in transfusion volume between the 3 groups was significant (P0.01). Hemodynamics was basically stable during operation in the 3 groups.ANH combined with controlled hypotension is safe and effective for decreasing and even avoiding homologous blood transfusion in liver tumorectomy.