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Synchronization of Kuramoto phase oscillators arranged in real complex neural networks is investigated. It is shown that the synchronization greatly depends on the sets of natural frequencies of the involved oscillators. The influence of network connectivity heterogeneity on synchronization depends particularly on the correlation between natural frequencies and node degrees. This finding implies a potential application that inhibiting the effects caused by the changes of network structure can be balanced out nicely by choosing the correlation parameter appropriately.

In alkaline condition(pH=9～10),a weak chemiluminescence signal was produced when H2O2 was injected into morin solution,and the chemiluminescence signal could be greatly enhanced after the introduction of cetyl trimethyl ammonium bromide(CTMAB) and sulfide.Based on the observation,H2O2-morin-CTMAB chemiluminescence system has been developed for the determination of sulfide.The possible mechanism of chemiluminescence reaction has also been discussed.Under the optimized conditions,the chemiluminescence intensity of the system presented a linear relationship with the concentration of sulfide in the range of(0.9～9.0)×10-8 g/mL,the linear dynamic equation was ΔICL=49.41+3.3612CS with correlation coefficient of 0.999 0.The detection limit(S/N=3) was 1.2×10-9 g/mL.The relative standard deviations(RSD) was 2.5% for 8.0×10-8 g/mL sulfide solution.The proposed method was successfully applied to the determination of sulfide in environmental water samples with recoveries in the range of 95.5%～101.3%.

We introduce composite implicititeration process with errors for approximation of common fixed points of general asymptotically nonexpansive mappings in Banach spaces, and we get strong convergence theorem.

High-quality ZnO and Cd-doped ZnO nanorods with different Cd-doping concentrations are synthesized by using the hydrothermal method. Microstructures and photoluminescence of the samples are systematically investigated by SEM, X-ray diffraction (XRD), Raman scattering spectrum and photoluminescence (PL) spectrum. Results of XRD analysis indicate that ZnO and ZnO:Cd crystallites exhibit a hexagonal wurtzite structure. SEM shows that the nanorods become smaller due to Cd doping. There is an internal tension which induces the decrease of optical band gap in Cd-doped nanorods. Cd-doping increases the intensity of violet emission peak near 2.90 eV and the blue emission peak located at 2.67 eV appears when the doping concentration is up to 2%. This study can be used for developing blue-violet-emitting devices.

Objectives Heart development is a strictly regulated process, and many gene families contribute to regulating genetic network to achieve this program. The homeobox genes are such a family encodes transcription factors, and it contains two closely related members, Shox and Shox2. During the embryonic cardiac development, Shox2 is restrictedly expressed in the sinoatrial node (SAN) and the sinus valves. Analyses of Shox2 knockout mouse models have demonstrated that Shox2 plays a crucial role during the SAN formation and the pacemaking system development. This study objective was to examine the ability of canine mesenchymal stromal cells (cMSCs) transfected with the mouse Shox2 gene to deliver a biological pacemaker. Methods We used lentivirus vectorto integrate the mouse Shox2 gene into the genome of cMSCs and were able to achieve stable expression of the Shox2 gene permanently. The cMSCs were randomised into two groups: the Shox2 group transfected with LV-Shox2- EGFP-cMSCs, and the control group transfected with LV-EGFP-cMSCs. Then all the positively transduced cMSCs were cultured with the new born rat myocardial cell lysate. After co-cultivation for seven days, we investigated the morphological changes of these transfected cMSCs. At the same time, the expression of cardiomyogenic markers Shox2 and HCN4 were determined by quantitative RT-PCR, Western Blot and immunofluorescence staining. In addition, the kinetics characters of I f like current channels were detected by whole-cellpatch clamp. Results Shox2 and HCN4 proteins were highly expressed in experimental group compared with the control group. Ahyperpolarization-activated inward current was recorded by whole-cell patchclamp in cMSCs transfected with Shox2 gene. The I f current recorded from the experimental group was sensitive to extracellular Cs + . Meanwhile, this current couldn’t be observed in control cells under the same conditions. Conclusions These results demonstrate that cMSCs modified by successful transfection with Shox2 can differentiate so as to develop spontaneous mechanical activity in vitro. Shox2 plays an essential role in the pacemaker development through the promotion of HCN4.