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In order to forecast the surface layer ozone concentration in the eastern coastal cities of China, an improved autoregressive method is used to dispose the ozone concentration data observed in November, 2008 in Tianjin, China in this paper. First the data are disposed by traditional auto-regressive model, then the real observed data are subtracted by the initial prediction value, through which the error terms are obtained. Next the error terms are disposed by filtering. The obtained filtered error terms are used in the AR model again and the new error terms are obtained, finally they are used to predict the concentration data a few hours ahead. Empirical results show that the proposed model is better than the traditional AR model, furthermore, the shorter the prediction time is, the better the model's prediction result is. So it is concluded that the proposed method is a nice method in predicting short term ozone concentration.

Model reaction of α-D-glucopyranosyl trimethylsilyl ether 1 with a series of acids demonstrated that stereocontrolled glucosyl transfer with the retention of configuration at the anomeric center is best carried out in dichloromethane at room temperature with boron trifluoride-ether as a Lewis acid catalyst. Under these conditions, I-O-acyl-α-D-glucopyranoses were obtained in good yield.

The band structures of 2D vacuum/solid square phononic crystals with cross-like holes are calculated by using the finite element method, the effects of geometric parameters on bandgaps are studied and compared with those of the phononic crystals with square holes. The numerical computation is performed by Comsol Multiphysics 3.5a. The results show that no bandgap exists for phononic crystals with square holes; while that by introducing cross-like holes, the degeneracy of the bands can be separated which gives rise to bandgaps. The geometric topology of the cross-like holes has distinct influence on the bandgaps. Still the systems are shown sensitive enough to the rotation angle of holes: with the increase of the rotation angle, the width of the lowest complete bandgap will enlarge monotonously for phononic crystals with square holes, but will decrease for the cross-like holes. The results are relevant to the optimization of the acoustic bandgaps.

H∞control problem of networked control systems with clock-driven sensor, actuator and event-driven actuator is studied. The sufficient condition of the existence of H∞ control law state feedback is derived through Lyapunov theory and linear matrix inequality. Design method is also presented. A simulation example shows the proposed approach is valid.

The study investigated the mechanism of the up-regulation of aquaporin-4 (AQP4) and aquaporin-1 (AQP1) expression induced by spinal cord injury (SCI). Using adult rat spinal cord injury model, it was found that up-regulation of hypoxia inducible factor-1α (HIF-1α), vascular endothelial growth factor (VEGF), AQP4, and AQP1 in response to spinal cord injury was greatly antagonized by 2-methoxyestradiol (2ME2), which can post-transcriptionally inhibit the expression of HIF-1α. VEGF alone significantly increased the extravasation of Evans blue and up-regulated the levels of AQP4 protein expression in the injured spinal cord issue, but the levels of AQP1 expression were not significantly changed. Taken together, our results suggest that expression of AQP4 and AQP1 is correlated with up-regulation of HIF-1α after SCI through the mechanisms that were dependent and independent of the VEGF signaling pathway, respectively. And the inhibitor of HIF-1α is a novel promising therapeutic agent for human SCI-induced edema in the future.

The study was performed to investigate whether the ischemic gray matter and white matter show distinct patterns of aquaporin-4 (AQP4) expression in the reperfusion phase using an in-vivo transient spinal cord ischemia model in rats. We investigated to the time course of AQP4 expression at the blood-spinal cord interface by the quantitative immunogold and western blots methods. The results showed that disruption of AQP4 anchoring at the perivascular membrane did not lead to a net loss of protein. This is the first systematic and extensive study fully showing AQP4 expression dynamics after transient spinal cord ischemia and the findings are of major clinical and experimental interest.

To observe the effects of neural stem cells (NSCs) transplantation on the brain derived neurotrophic factor (BDNF) after the spinal cord injury (SCI) of rats, and to investigate the mechanism of repairing the SCI by NSCs transplantation.Neural stem cells were cultured from the hippocampus of rats' embryo and identified by immunocytochemistry. Seven days after the operation of SCI, the NSCs were transplanted into the injured site. Sixty adult Wistar rats were randomly divided into three groups: SCI cured with NSCs transplantation (group A), SCI received DMEM solution (group B), control group (group C). Then the expression of BDNF of the lesion and neighbor areas were examined by reverse transcsription polymerase chain reaction (RT-PCR) and immunohistochemistry, so as to investigated the mechanism of repairing the SCI after NSCS transplantation.According the RT-PCR results analysis, the expression of BDNF mRNA of group A enhanced higher than that of group B on the 1st, 3rd, 5th day after transplantation of NSCs. According the immunohistochemistry results analysis, the expression of BDNF mRNA of group A enhanced higher than that of group B on the 7th, 14th, 28th day similarly.The transplantation of NSCs can change the tiny-entironment by upregulating the expression of BDNF. It maybe one of the mechanism of repairing the SCI by NSCs transplantation.

A novel aluminum complex, Al(DTP) 3 (DTP=1,3-di-(2-thienyl)-1,3-propanedione), was synthesized and applied to an organic eletroluminescent (EL) device as an emitting material and an electron transporting material. The double layered EL device was fabricated by using triphenyldiamine derivative (TPD) as a hole transporting layer and Al(DTP) 3 as an active emitting layer sandwiched between indium-tin-oxide (ITO) and an alloy of Al/Li (99:1) electrodes. The deposited EL device was observed to emit a bright yellow light originating from Al(DTP) 3 with a maximum luminance of 400 cd/m 2 at 17 V and 400 mA/cm 2 .

To observe the effects of cryopreserved (-70 degrees C) neural stem cells (NSCs) transplantation on the axon regeneration after the spinal cord injury (SCI) of rats.Neural stem cells were cultured from the hippocampus of the rat's embryo and identified by immunocytochemistry of nestin, then NSCs in logarithmic phage were cryopreserved (-70 degrees C) for 2 weeks. Seven days after the operation of SCI, the NSCs in were transplanted into the injured site immediately. Thirty six adult Wistar rats were randomly divided into three groups: spinal cord injury treated with transplantation of NSCs to the injured site (Group A), spinal cord injury received DMEM solution (Group B), control group (Group C). Then NSCs labeled with Brdu were detected by immunohistochemisty, and the reconstruction of spinal cord were detected by horseradish peroxidase (HRP) staining.NSCs can be detected in the spinal cord after transplantation. The number of HRP positive cells of Group A was higher than that of Group B.The transplantation of cryopreserved NSCs can survived in the injured site and promote the reconstruction. It may be a progress in the repairing of the SCI by cells transplantation.

The study was performed to investigate the effect of combination therapy with aminoguanidine (AG) and dexamethasone (DEX) on the compression spinal cord injury (SCI) in rat. Compared to the control group, the combination therapy group with AG (75 mg/kg) and DEX (0.025 mg/kg) significantly reduced the degree of (1) spinal cord edema, (2) the permeability of blood spinal cord barrier (measured by (99m)Tc-Albumin), (3) infiltration of neutrophils (MPO evaluation), (4) cytokines expression (tumor necrosis factor-alpha and interleukin-1 beta), and (5) apoptosis (measured by Bax and Bcl-2 expression). In addition, we have also clearly demonstrated that the combination therapy significantly ameliorated the recovery of limb function (evaluated by motor recovery score). Taken together, our results clearly indicated for the first time that strategies targeting multiple proinflammatory pathways may be more effective than a single effector molecule for the treatment of SCI.

In this series of studies, the innervation patterns of whole-mount preparations of bicuspid and tricuspid valves were studied by light microscopy in the mouse, rat, guinea pig, and opossum. The acetylcholinesterase-positive networks of nerve fibers showed many similarities in the basic patterns of valve innervation in all of the species studied, but several interspecies variations were observed. The basal zone of the valve adjacent to the fibromuscular atrioventricular ring displayed the most dense plexus of nerves, with acetylcholinesterase-positive fibers being seen across the width of the valve. In the intermediate zone of the valve, less dense plexuses of nerve fibers were found; and these were more numerous in the cuspal areas and less numerous in the intervening commissural areas. In the distal portions of the valve, nerve networks arborized extensively, with some of their nerve fibers extending toward the chordae tendineae and the free edges of the valve cusps. Only in the guinea pig and opossum did these fibers reach the free margin of the valve cusp, where they either ended directly as free nerve endings or lay parallel to the free edge of the cusp, often running between adjacent chordae tendineae. Although the patterns of innervation were similar in both bicuspid and tricuspid valves, the innervation density of the bicuspid valve was greater than that of the tricuspid valve for each species examined. A distinguishing feature of guinea pig and opossum tricuspid valves was that their chordae tendineae were relatively more prominent and more densely innervated than the bicuspid chordae tendineae. Free nerve endings with no light microscopic evidence of specialization were present throughout the bicuspid and tricuspid valves of all species studied. Some nerve endings in the opossum showed evidence of specialization, with brush-like arborizations leading to presumed free terminals seen chiefly in the distal zone of the valve cusps. Although some general tendencies were apparent, we have demonstrated that interspecies heterogeneity exists in the terminal networks of the atrioventricular valves of mouse, rat, guinea pig, and opossum.

In this paper we propose various types of two-dimensional (2D) square zigzag lattice structures, and we study their bandgaps and directional propagation of elastic waves. The band structures and the transmission spectra of the systems are calculated by using the finite element method. The effects of the geometry parameters of the 2D-zigzag lattices on the bandgaps are investigated and discussed. The mechanism of the bandgap generation is analyzed by studying the vibration modes at the bandgap edges. Multiple wide complete bandgaps are found in a wide porosity range owing to the separation of the degeneracy by introducing bending arms. The bandgaps are sensitive to the geometry parameters of the systems. The deformed displacement fields of the transient response of finite structures subjected to time-harmonic loads are presented to show the directional wave propagation. The research in this paper is relevant to the practical design of cellular structures with enhanced vibro-acoustics performance.

In this paper, we present a combined theoretical, numerical and experimental study of acoustic wave propagation in 1D locally resonant phononic crystals made of acoustic resonators grafted onto a waveguide. The case of one single resonator grafted onto the waveguide is first investigated and a model of transmission cancellation at resonant frequencies is obtained. The model includes the excitation of evanescent guided waves attached to the grafting points. When extended to periodical arrays of grafted resonators, the model provides us with a definite theoretical expression for the complex band structure. Comparison with experimental results and complex band structures obtained by numerical simulation suggests a strong dependence of transmission through the crystal on the lattice constant of the grafted resonators. It is found that evanescent waves in the waveguide play a key role when the lattice constant is in the sub-wavelength range.

Two-dimensional ternary locally resonant phononic crystals used to consist of cylindrical scatterers with uniform coatings in their exterior. An alternative coating scheme with a comblike profile is proposed and investigated in this letter. The band structures are calculated by using the finite element method. It is found that a complete bandgap at a significantly low frequency can be induced. The mechanism for such a change is suggested by using an equivalent spring-mass model based on analyzing the eigen modes at the bandgap edges. Consistent results are obtained from the numerical results and the analysis of the spring-mass model., 13 pages, 8 figures

The bandgap properties of an open or covered phononic crystal slab with resonators are studied by using the finite element method. The results show that complete bandgap comes up for the proposed slabs with resonators due to the local resonance. The effects of the topological geometry of the resonators on the bandgaps are discussed, and optimal geometry is suggested. The mechanism of the bandgap generation is analyzed by studying the eigen modes at the bandgap edges. Equivalent spring-mass/pendulum models are developed to predict the eigen frequencies at the lower bandgap edges. The evaluated results obtained by the equivalent models are in general agreement with the numerical ones. The work in this paper is indispensable to the optimal design of the bandgaps of phononic crystal slabs.

In this paper, we study the influences of material parameters on the phononic band gaps of three-dimensional (3D) solid phononic crystals (PCs) based on the finite difference time domain (FDTD) method. We begin with the basic wave equations and the FDTD formulation to derive the material parameters directly determining the band gaps of the 3D solid PCs. The parameters include the transverse velocity ratio, the acoustic impedance ratio and the Poisson ratios (or equivalently, the mass density ratio, the shear modulus ratio and the Poisson ratios) of the scatterers and host materials. The negative Poisson ratio is also considered in our investigation. The effects of these material parameters on band gap width are discussed based on detailed numerical calculations for systems with three typical lattices. The generation mechanism of band gaps (Bragg scattering or local resonance) which is determined by the material parameters is also discussed. The analysis is expected to be applied to the artificial design of 3D phononic band gap materials.

We theoretically demonstrate the existence of simultaneous large complete photonic and phononic bandgaps in three-dimensional dielectric phoxonic crystals with a simple cubic lattice. These phoxonic crystals consist of dielectric spheres on the cubic lattice sites connected by thin dielectric cylinders. The simultaneous photonic and phononic bandgaps can exist over a wide range of geometry parameters. The vibration modes corresponding to the phononic bandgap edges are the local torsional resonances of the dielectric spheres and rods. Detailed discussion is presented on the variation of the photonic and phononic bandgaps with the geometry of the structure. Optimal geometry which generates large phoxonic bandgaps is suggested.

A new haemocompatible phospholipid polyurethane based on hydrogenated poly(isoprene) glycol (HPIP) and 4,4'-methylendiphenyl diisocyanate (MDI) was synthesized using 2-[bis(2-hydroxyethyl)methyl-ammonio]ethylstearylphosphate (BESP) and 1,4-butanediol (BD) as chain extender. The bulk and surface characteristics of this material was investigated by differential scanning calorimetry (DSC), dynamic viscoelasticity and tensile property measurements, attenuated total reflectance-Fourier transform infrared spectroscopy (ATR-FTIR), and contact angle measurement. This polymer possessed a hydrophobic surface revealed by contact angle measurement. The haemocompatibility of this polyurethane was evaluated by platelet rich plasma (PRP) contacting studies and scanning electron microscopy (SEM) observation using medical grade poly(vinyl chloride) (PVC) as the reference. The results show that this new polyurethane had relatively lower platelet adhesion and limited shape change for the attached platelets compared to PVC. The clotting time of the materials in contact with platelet poor plasma (PPP) was 99, 75, and 62 s and in contact with PRP was more than 240, 100, and 86 s for new polyurethane, PVC, and glass, respectively. This new phospholipid polyurethane is expected to have wide applications as coating or structural material for blood-contacting medical equipment due to its outstanding haemocompatibility and excellent mechanical strength.

In this paper we study the bandgap properties of two-dimensional phononic crystals with cross-like holes using the finite element method. The influence of the geometry parameters of the holes on the bandgaps is discussed. In contrast to a system of square holes, which does not exhibits bandgaps if the symmetry of the holes is the same as that of the lattice, systems of cross-like holes show large bandgaps at lower frequencies. The bandgaps are significantly dependent upon the geometry (including the size, shape, and rotation) of the cross-like holes. The vibration modes of the bandgap edges are computed and analyzed in order to clarify the mechanism of the generation of the lowest bandgap. It is found that the generation of the lowest bangdap is a result of the local resonance of the periodically arranged lumps connected with narrow connectors. Spring-mass models are developed in order to predict the frequencies of the lower bandgap edges. The study in this paper is relevant to the optimal design of the bandgaps in light porous materials.

A novel europium complex, Eu(DFP)3(phen)(DFP=1,3-Di-(2-furyl)-1,3-propanedione, phen=1,10-phenanthroline), was synthesized and used as an emitting material in organic eletroluminescent (EL) devices. The structure of fabricated EL devices is composed of ITO/TPD/Eu(DFP)3(phen)/AlLi(99:1). The double layered EL device emitted red light originating from Eu(DFP)3(phen) with a maximum luminance of 34.3 cd/m2 at 12 V and 25.7 mA/cm2.

A facile Method for the synthesis of alkyl α- and β-D-glucopyranosides using 1-0-trimethylsilyt-2,3,4,6-tetra-O-benzyl-α-D-glucopyranose by the promotion of BF3ET2O was reported. The mixture of α -and β-anomers, in which β-anomers predominated, was obtained in good yields.