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In order to improve the braking performance and safety performance of electric vehicles driven by a hub motor, the cylinder pressure estimation and pressure control of its hydraulic braking system are studied. In this paper, a mathematical model is established for the solenoid valve, a key component of the hydraulic actuator, and the hydraulic and electrical characteristics of the solenoid valve are studied. A state equation is established for the solenoid valve, and the square root volume Kalman filter (SRCKF) algorithm is used to estimate the solenoid valve spool position. The brake fluid flow and brake wheel cylinder pressure are calculated based on the spool position. Finally, a solenoid valve spool position control algorithm based on sliding mode variable structure algorithm is designed, and the brake pressure in the brake wheel cylinder is controlled by adjusting the spool position. Matlab/Simulink-AMESim software simulation and hardware-in-the-loop were used to verify the algorithm. Simulation results show that the brake cylinder pressure can be estimated accurately, and the pressure control algorithm can accurately follow the control target value. [ABSTRACT FROM AUTHOR]

In order to control joints of manipulators with high precision, a position tracking control strategy combining fractional calculus with iterative learning control and sliding mode control is proposed for the control of a single joint of manipulators. Considering the coupling between joints of manipulators, a fractional-order iterative sliding mode crosscoupling control strategy is proposed and the theoretical proof of its progressive stability is given. The paper takes a two-joint manipulator as the research object to verify the control strategy of a single-joint manipulator. The results show that the control strategy proposed in this paper makes the two-joint mechanical arm chatter less and the tracking more accurate. The synchronous control of the manipulator is verified by a three-joint manipulator. The results show that the angular displacement adjustment times of the threejoint manipulator are 0.11 s, 0.31 s and 0.24 s, respectively. 3.25 s > 5 s, 3.15 s of a PD cross-coupling control strategy; 2.85 s, 2.32 s, 4.22 s of a PD iterative cross-coupling control strategy; 0.14 s, 0.33 s, 0.28 s of a fractional-order sliding mode cross-coupling control strategy. The root mean square error of the position error of the designed control strategy is 6.47 × 10-6 rad, 3.69 × 10-4 rad, 6.91 × 10-3 rad, respectively. The root mean square error of the synchronization error is 3.96×10-4 rad, 1.36×10-3 rad, 7.81×10-3 rad, superior to the other three control strategies. The results illustrate the effectiveness of the proposed control method. [ABSTRACT FROM AUTHOR]

Background This report describes emergency response following an imported vaccine derived poliovirus (VDPV) case from Myanmar to Yunnan Province, China and the cross-border collaboration between China and Myanmar. Immediately after confirmation of the VDPV case, China disseminated related information to Myanmar with the assistance of the World Health Organization. Methods A series of epidemiological investigations were conducted, both in China and Myanmar, including retrospective searches of acute flaccid paralysis (AFP) cases, oral poliovirus vaccine (OPV) coverage assessment, and investigation of contacts and healthy children. Results All children <2 years of age had not been vaccinated in the village where the VDPV case had lived in the past 2 years. Moreover, most areas were not covered for routine immunization in this township due to vaccine shortages and lack of operational funds for the past 2 years. Conclusions Cross-border collaboration may have prevented a potential outbreak of VDPV in Myanmar. It is necessary to reinforce cross-border collaboration with neighboring countries in order to maximize the leverage of limited resources. [ABSTRACT FROM AUTHOR]

Soil salinity is an increasingly serious problem worldwide that reduces agricultural output potential. Selected beneficial soil bacteria can promote plant growth and augment tolerance to biotic and abiotic stresses. Bacillus subtilis strain GB03 has been shown to confer growth promotion and abiotic stress tolerance in the model plant Arabidopsis thaliana. Here we examined the effect of this beneficial soil bacterium on salt tolerance in the legume forage crop, white clover. Plants of white clover (Trifolium repens L. cultivar Huia) were grown from seeds with or without soil inoculation of the beneficial soil bacterium Bacillus subtilis GB03 supplemented with 0, 50, 100, or 150mM NaCl water into soil. Growth parameters, chlorophyll content, malondialdehyde (MDA) content and osmotic potential were monitored during the growth cycle. Endogenous Na+ and K+ contents were determined at the time of harvest. White clover plants grown in GB03-inoculated soil were significantly larger than non-inoculated controls with respect to shoot height, root length, plant biomass, leaf area and chlorophyll content; leaf MDA content under saline condition and leaf osmotic potential under severe salinity condition (150mM NaCl) were significantly decreased. Furthermore, GB03 significantly decreased shoot and root Na+ accumulation and thereby improved K+/Na+ ratio when GB03-inoculated plants were grown under elevated salt conditions. The results indicate that soil inoculation with GB03 promotes white clover growth under both non-saline and saline conditions by directly or indirectly regulating plant chlorophyll content, leaf osmotic potential, cell membrane integrity and ion accumulation. [ABSTRACT FROM AUTHOR]

Coronary heart disease (CHD) is highly prevalent globally and a major cause of mortality. Genetic predisposition is a non-modifiable risk factor associated with CHD. Eighty-four Chinese patients with CHD and 253 healthy Chinese controls without CHD were recruited. Major clinical data were collected, and a single nucleotide polymorphism (SNP) in the stromal cell-derived factor 1 (SDF-1) gene at position 801 (G to A, rs1801157) in the 3'-untranslated region was identified. The correlation between rs1801157 genotypes and CHD was evaluated by a multivariate logistic regression analysis. The allele frequency in the CHD and control groups was in Hardy-Weinberg equilibrium (HWE) (p > 0.05). The frequency of the GG genotype in the CHD group (59.5%) was significantly higher than that in the control group (49.8%) (p = 0.036). A number of variables, including male sex, age, presence of hypertension, and the levels of low-density lipoprotein cholesterol (LDL-C), high-density lipoprotein cholesterol (HDL-C), triglycerides (TG), uric acid, and total bilirubin, were associated with CHD in a primary univariate analysis. In a multivariable logistic regression analysis, the GG genotype (GG:AA, odds ratio (OR) = 2.31, 95% confidence interval (CI) = 1.21-5.23), male sex, advanced age (≥60 years), presence of hypertension, LDL-C level ≥ 3.33 mg/dL, HDL-C level < 1.03 mg/dL, and TG level ≥ 1.7 mg/dL were independent risk factors for CHD. [ABSTRACT FROM AUTHOR]

Background After being polio free for more than 10 years, an outbreak occurred in China in 2011 in Xinjiang Uygur Autonomous Region (Xinjiang) following the importation of wild poliovirus (WPV) originating from neighboring Pakistan. Methods To strengthen acute flaccid paralysis (AFP) surveillance in Xinjiang, "zero case daily reporting" and retrospective searching of AFP cases were initiated after the confirmation of the WPV outbreak. To pinpoint all the polio cases in time, AFP surveillance system was expanded to include persons of all ages in the entire population in Xinjiang. Results Totally, 578 AFP cases were reported in 2011 in Xinjiang, including 21 WPV cases, 23 clinical compatible polio cases and 534 non-polio AFP cases. Of the 44 polio cases, 27 (61.4%) cases were reported among adults aged 15-53 years. Strengthening AFP surveillance resulted in an increase in the number of non-polio AFP cases in 2011 (148 children < 15 years) compared with 76 cases < 15 years in 2010. The AFP surveillance system in Xinjiang was sensitive enough to detect polio cases, with the AFP incidence of 3.28/100,000 among children < 15 years of age. Conclusions Incorporating adult cases into the AFP surveillance system is of potential value to understand the overall characteristics of the epidemic and to guide emergency responses, especially in countries facing WPV outbreak following long-term polio free status. The AFP surveillance system in Xinjiang was satisfactory despite limitations in biological sample collection. [ABSTRACT FROM AUTHOR]

Background: Existing standard non-molecular diagnostic methods such as viral culture and immunofluorescent (DFA) are time-consuming, labor intensive or limited sensitivity. Several multiplex molecular assays are costly. Therefore, there is a need for the development of a rapid and sensitive diagnosis of respiratory viral pathogens. Methods: A GeXP-based multiplex RT-PCR assay (GeXP assay) was developed to detect simultaneously sixteen different respiratory virus types/subtypes. Seventeen sets of chimeric primers were used to initiate the RT-PCR, and one pair of universal primers was used for the subsequent cycles of the RT-PCR. The specificity of the GeXP assay was examined with positive controls for each virus type/subtype. The sensitivity was evaluated by performing the assay on serial ten-fold dilutions of in vitro-transcribed RNA of all RNA viruses and the plasmids containing the Adv and HBoV target sequence. GeXP assay was further evaluated using 126 clinical specimens and compared with Luminex xTAG RVP Fast assay. Results: The GeXP assay achieved a sensitivity of 20-200 copies for a single virus and 1000 copies when all of the 16 pre-mixed viral targets were present. Analyses of 126 clinical specimens using the GeXP assay demonstrated that GeXP assay and the RVP Fast assay were in complete agreement for 109/126 (88.51%) of the specimens. GeXP assay was more sensitive than the RVP Fast assay for the detection of HRV and PIV3, and slightly less sensitive for the detection of HMPV, Adv, RSVB and HBoV. The whole process of the GeXP assay for the detection of 12 samples was completed within 2.5 hours. Conclusions: In conclusion, the GeXP assay is a rapid, cost-effective, sensitive, specific and high throughput method for the detection of respiratory virus infections. [ABSTRACT FROM AUTHOR]

A new method for parameter optimization of pharmacokinetics based on an artificial immune network named PKAIN is proposed. To improve local searching ability of the artificial immune network, a partition-based concurrent simplex mutation is developed. By means of evolution of network cells in the PKAIN artificial immune network, an optimal set of parameters of a given pharmacokinetic model is obtained. The Laplace transform is applied to the pharmacokinetic differential equations of remifentanil and its major metabolite, remifentanil acid. The PKAIN method is used to optimize parameters of the derived compartment models. Experimental results show that the two-compartment model is sufficient for the pharmacokinetic study of remifentanil acid for patients with mild degree of renal impairment. [ABSTRACT FROM AUTHOR]

Phylogenetic analysis of a collection of 103 El gene sequences from rubella viruses isolated from 17 countries from 1961 to 2000 confirmed the existence of at least two genotypes. Rubella genotype I (RGI) isolates, predominant in Europe, Japan, and the Western Hemisphere, segregated into discrete subgenotypes; international subgenotypes present in the 1960s and 1970s were replaced by geographically restricted subgenotypes after ∼1980. Recently, active subgenotypes include one in the United States and Latin America, one in China, and a third that apparently originated in Asia and spread to Europe and North America, starting in 1997, indicating the recent emergence of an international subgenotype. A virus that potentially arose as a recombinant between two RGI subgenotypes was discovered. Rubella genotype II (RGII) showed greater genetic diversity than did RGI and may actually consist of multiple genotypes. RGII viruses were limited to Asia and Europe; RGI viruses were also present in most of the countries where RGII viruses were isolated. [ABSTRACT FROM AUTHOR]