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This paper presents the stress and strain distribution and change during the tunnel construction, and the stress and strain are compared with different construction methods. Mathematical model was firstly introduced. Then the stress and the strain during the up tunnel construction from two methods were compared. The historical stress and strain curves of key node of tunnel during the tunnel construction were analyzed. The different stress changes from different construction methods were compared. We can get the conclusion that the construction method affects the stress distribution and change.

It is a kind of effective way to study blasting to joint rock mass using the finite element method, in which the key is algorithm and model building. Comparing the relationship of explosive and blasting structure simulated by adopting Lagrange method and ALE method, the paper considers that Lagrange method is more close to practice, and could finish numerical simulation analysis of the intact rock blasting.

This paper presents a dynamic calibration method of frequency response characteristics of high-pressure sensor. In this method, the pressure sensor was under high hydrostatic pressure in advance, then use the bullet impacted Hopkinson bar and generated quasi-δ function signal with small amplitude, which excited the sensor being calibrated. The excitation signal of sensor are collected, at the same time, output signal of the sensor are collected, and at last, the collected data are processed according to calibration principle and calculated the frequency response of the sensor being calibrated. This calibration method realized dynamic calibration of high pressure sensor under actual working pressure; it can realize the low limit frequency of the calibrated frequency range strictly reaches to zero frequency. This method can also be applied to acceleration sensor, transient high-temperature sensor, and other types of sensors. In this paper, the calibration principle of quasi-δ function dynamic calibration method is introduced. The relationship among pulse width of excitation signal, frequency range that can be calibrated and calibration precision is analyzed. The experimental results are also shown.

On the basis of publicized data, the fractal character of pore structure in loess is studied. We have determined fractal characteristic pore radius and discussed the relationship between fractal character values and collapsibility. Results show that there is a good linear relationship between and collapsibility, and fractal dimension can reflect geological age of loess section.

This study aims to evaluate the impact of pretreatment thrombocytosis on survival in patients with nasopharyngeal carcinoma (NPC). The data of 1,582 patients with NPC, who underwent definitive treatment between 2003 and 2004, were retrospectively reviewed. The correlation between the clinicopathological variables and the platelet count was analyzed. The prognostic significance of thrombocytosis, together with various clinicopathological factors, was evaluated by univariate and multivariate analyses. Platelet count showed significant correlation with gender, clinical stage, and T stage in univariate analysis. There was poorer 5-year disease-specific survival (DSS) in the patients with thrombocytosis than in those without thrombocytosis (70 vs. 78 %; p = 0.001) and poorer metastases-free survival (MFS) (81 vs. 88 %; p = 0.006). Univariate and multivariate analyses showed that thrombocytosis was an independent prognostic factor for MFS and DSS. Thrombocytosis is a useful predictor of metastasis and poor prognosis in patients with NPC.

16-channel EEG data during intermittent episodes of epilepsy is recoded and analyzed to find the lesions source for temporal lobe epilepsy by Granger causality. And the analysis of EEG with the lesions of temporal lobe epilepsy and non-lesions area of relationship between cause and effects is focused on, exploring temporal lobe epilepsy with lesions in other regions of the information transduction relationship for the clinical determination of temporal lobe epileptic focus to provide a theoretical the support. There are 8 cases patients which 6 cases patients of left-temporal lobe epilepsy and 2 cases patients of right-temporal lobe epilepsy in this work, Sampling frequency fs=200Hz，time t=20s (Sampling points N=4000). Granger causality is used to direction of the information transduction between each channel of the EEG signals. Autoregressive methods of EEG analysis for multi-channel data and determination of the coefficient of the matrix A, and proportion of operations on the matrix A is applied to get the result of matrix I which can reflect the causal relationship between each channel. The result shows that Granger causality can test the location of the lesions source and the areas that the information was reached. The results are consistent with the diagnosis of the EEG and CT. Granger causality not only can analyze the causal relationship of EEG, and it can calculate the multi-channel information transduction between the directions of EEG, which can provide support in the clinic for determine the source of seizure.

As a conductive fillers, graphite nanosheets can be induced by the AC electric field in unsaturated polyester resin and then prepared oriented unsaturated polyester resin/graphite nanosheets composite. We investigate the preparation, configuration and capability of the unsaturated resin/ graphite nanosheets conductive composites and the oriented theory of the graphite nanosheets induced in the electric field. The measures and observation of scanning electron microscopy(SEM), X-ray diffraction(XRD), electric current have shown that the graphite nanosheets are oriented by electric field which were randomly dispersed in the polymer matrix at the beginning, and then oriented with their flakes along the electric field in the polyester resin.

Plants utilize multiple layers of defense mechanisms to fight against the invasion of diverse pathogens. The R gene mediates resistance, in most cases, dependent on the co-existence of its cognate pathogen-derived avirulence (Avr) gene. The rice blast R gene Piz-t corresponds in gene-for-gene fashion to the Magnaporthe oryzae Avr gene AvrPiz-t. In this study, we determined and compared the genomic sequences surrounding the AvrPiz-t gene in both avirulent and virulent isolates, designating as AvrPiz-t-ZB15 and avrPiz-t-70-15 regions, respectively. The sequence of the AvrPiz-t-ZB15 region is 120 966 bp whereas avrPiz-t-70-15 is 146 292 bp in length. The extreme sequence similarity and good synteny in gene order and content along with the absence of two predicted genes in the avrPiz-t-70-15 region were observed in the predicted protein-coding regions in the AvrPiz-t locus. Nevertheless, frequent presence/absence and highly dynamic organization of transposable elements (TEs) were identified, representing the major variation of the AvrPiz-t locus between different isolates. Moreover, TEs constitute 27.3% and 43.2% of the genomic contents of the AvrPiz-t-ZB15 and avrPiz-t-70-15 regions, respectively, indicating that TEs contribute largely to the organization and evolution of AvrPiz-t locus. The findings of this study suggest that M. oryzae could benefit in an evolutionary sense from the presence of active TEs in genes conferring avirulence and provide an ability to rapidly change and thus to overcome host R genes.

Semi-self-fluxing iron powder is identified by self-fluxing nature or alkalinity ,they contain part of CaO and MgO. To make full use of resource and improve pellets quality,do a series of tests. The results show that semi-self-fluxing iron powder can improve pellets metallurgical properties. Put forward the appropriate mixing proportion and roasting temperature.

In this study, a numerical model was built to simulate the self-piercing riveting (SPR) process using commercial LS-DYNA finite element code. The difficulties in numerical simulation of the SPR process, such as large deformation and fracture, were resolved by the use of an explicit solution process combined with the r-adaptive meshing method. The model was applied to joining two sheets of 6061 aluminium alloy. The effects of die geometry, rivet material properties and the adaptive step size in numerical calculation were studied, using 6061 aluminum sheets as a model system. The simulation agrees well with the experimental results in terms of geometric characterisitcs of the cross-sections of the joints formed.

Three new steroidal compounds with polyhydroxy groups, tupisteroide A-C (1-3), were obtained from the roots of Tupistra chinensis, together with one known compound (4) that was isolated from this plant for the first time. The structures of tupisteroide A-C were determined on the basis of one- and two-dimensional NMR spectroscopy, including (1) H-(1) H Correlation Spectroscopy, Heteronuclear Multiple Bond Correlation, and Heteronuclear Single Quantum Coherence experiments. The isolated compounds were evaluated for their cytotoxic activities against A549, HepG2, and CaSki cancer cell lines in vitro. Among them, compounds 1, 2, and 4 did not show significant inhibitory activity, but compound 3 showed cytotoxicity against A549 cancer cell lines with IC(50) values of 25.0 μM.

The active site of chitosan is protected basing on amino reaction method of reaction between benzaldehyde and chitosan to form Schiff. The O-carboxymethyl chitosan is obtained by the method that taking chloroactic acid to hydroxyl of chitosan as modifier in alkaline conditions to form amino protection and then remove the protection in acid conditions. The O-carboxymethyl chitosan particles with particle size distribution of 15-50μm is prepared by emulsification cross- linking method.

There were problems of strong electromagnetic interfere (EMI) and floating of ground potential when the electrothermal-chemical gun (ETCG) was launched. EMI seriously affected the chamber pressure measurement, and affected the accurateness of data and the security of apparatus. The chamber pressure testing technology was put forward which adopted the field testing technique with digital storage and the digital optical fiber transmission technique. The on-site storage pressure gauge and multilayer electromagnetic shielding structure was designed. Test data real-time transmission and remote reappear are realized by using high speed digital optical transceiver module and optical fiber. This testing technology effectively solved the EMI problem, improved the reliability and safety of chamber pressure measurement. The test data provide a basis for research of interior ballistic properties of ETCG. This testing technology can be widely applied to the parameters measurement with strong electromagnetic interfere.

A semi-continuum approach is developed for mechanical analysis of a silicon nanobeam, which captures the atomistic physics and retains the efficiency of continuum models. Young’s modulus of the silicon (001) nanobeam along [100] direction is obtained by the developed semi-continuum approach, which decreases dramatically as the size of a silicon nanobeam width and thickness scaling down. Taking into account the variations of Young’s modulus at different size, the load properties of the nanobeam is computed. The model predicts the deflection of the nanobeam is size-dependence. Introduction

As conductive fillers, graphite nanosheets can be induced by the AC electric field in unsaturated polyester resin and then prepared oriented unsaturated polyester resin/graphite nanosheets composite. we investigate the preparation、configuration and capability of the unsaturated resin/graphite nanosheets conductive composites and the oriented theory of the graphite nanosheets induced in the electric field. The measures and observation of scanning electron microscopy (SEM), X-ray diffraction (XRD), electric current have shown that the graphite nanosheets are oriented by electric field which were randomly dispersed in the polymer matrix at the beginning, and then oriented with their flakes along the electric field in the polyester resin.

Existing frequency-domain-oriented methods of parameter identification for uniform linear motion blur (ULMB) images usually dealt with special scenarios. For example, blur-kernel directions were horizontal or vertical, or degraded images were of foursquare dimension. This excludes those identification methods from being applied to real images, especially to estimate undersized or oversized blur kernels. Pointing against the limitations of blur-kernel identifications, discrete Fourier transform (DFT)-based blur-kernel estimation methods are proposed in this paper. We analyze in depth the Fourier frequency response of generalized ULMB kernels, demonstrate in detail its related phase form and properties thereof, and put forward the concept of quasi-cepstrum. On this basis, methods of estimating ULMB-kernel parameters using amplitude spectrum and quasi-cepstrum are presented, respectively. The quasi-cepstrum-oriented approach increases the identifiable blur-kernel length, up to a maximum of half the diagonal length of the image. Meanwhile, directing toward the image of undersized ULMB, an improved method based on quasi-cepstrum is presented, which ameliorates the identification quality of undersized ULMB kernels. The quasi-cepstrum-oriented approach popularizes and applies the simulation-experiment-focused DFT theory to the estimation of real ULMB images. Compared against the amplitude-spectrum-oriented method, the quasi-cepstrum-oriented approach is more convenient and robust, with lower identification errors and of better noise-immunity.

Unsaturated polyester resin/Graphite nanosheet composites were prepared using in situ polymerization under AC electric field which was applied during composite curing to induce orientation of graphite nanosheets. Scanning electron microscopy (SEM) has been applied to demonstrate the orientation of graphite nanosheets As a result, the percolation threshold was decreased to 0.25 wt% due to the orientation of the graphite nanosheets.

Graphite nanosheets (GNs) prepared by sonicating expanded graphite were homogeneously dispersed in unsaturated polyester resin using sonication. The dispersion with a curing agent was then subjected to a dc electric field, followed by crosslinking, to fabricate a polymer/GN composite film. Scanning electron microscopy revealed that the GNs in the film were oriented parallel to the electric field. UV-VIS measurements indicated that the optical properties of the field-induced composite film showed significant improvement in visible light transmittance compared with those prepared without the electric field.

In Drosophila, presenilin is an aspartyl protease that plays important roles in the development and calcium homeostasis. It has been expressed all through the fly developmental process. The loss of Drosophila presenilin (DPS) function causes significantly decreased Notch signaling and neuron apoptosis and increased cytoplasm calcium. This subsequently led to impaired long term memory and cognitive deficits. Therefore, study of DPS is one of the most popular models for Alzheimer's disease research, and has provided important insights into the pathological mechanisms of AD. This review is to summarize the AD related function of DPS gene.

In this paper, we present theoretical analysis and detailed design of a class of wireless power transfer (WPT) systems based on strong coupled magnetic resonances. We established the strong coupled resonance conditions for practically implementable WPT systems. We investigated the effects of non-ideal conditions presented in most practical systems on power transfer efficiency and proposed solutions to deal with these problems. We carried out a design of WPT system by using PCB (Printed Circuit Board) antenna pair, which showed strong coupled magnetic resonances. The innovations of our design include: (1) a new coil winding pattern for resonant coils that achieves a compact space volume, (2) fabrication of resonant coils on PCBs, and (3) integration of the entire system on a pair of PCBs. Extensive experiments were performed and experimental results showed that our WPT system setup achieved a guaranteed power transfer efficiency 14% over a distance of two times characteristic length(44cm). The wireless power transfer efficiency in this PCB based experimental system was sufficiently high to lighten up a LED with a signal generator.

In this article, Spiral belt static mixer with changing diameter was taken as the object. The numerical simulation method was used to investigate the mixing process of two-phase liquid–liquid flow in water treatment by a commercial CFD code,namely Fluent.The k-ε model and species transport model were established to research this project. Then the mixing effect was compared with that of HEV static mixer. The result showed that spiral belt static mixer with changing diameter promote the mixing effect greatly. The mixing effect relative to that of HEV static mixer increased 10 times and the the pressure loss only increased 3 times.

Based on the supercharged boiler thermodynamic calculation method and turbocharged set characteristic calculation method, an integrated model used for studying the matching performance was built, and then the matching performance calculation program chart was made. Taking a type of marine supercharged boiler as the research object, the matching performance of supercharged boiler and turbocharged set, which was changed with excess air coefficient, was studied under different loads. The model is proved correct and effective by the comparison of the design value and calculation value. The analysis results can provide a strong technology support to the supercharged boiler set’s optimized design and safety operation, which means theoretical and practical significance

The dissipation dynamics and final residues of fluopyram in cucumber and soil were studied. Cucumber and soil samples were extracted with acetonitrile, cleaned up by PSA, determined by gas chromatography with electron capture detection. The LOQ of this method was found 0.003 mg/kg. The results of residual dynamics experiment showed that the half-lives of fluopyram in cucumber and soil were 3.7-4.3 days and 5.8-6.2 days, respectively. Residues of fluopyram in cucumber were all below 0.5mg/kg at both recommended high dosage and 1.5 times of recommended high dosage.

The existing concrete structures, especially hydraulic dams, in the cold areas of northern China have suffered from freeze-thaw damages to varying degrees in the small part or the vast areas of the projects. This paper will work out the performance deterioration index with the relative dynamic elastic modulus and the mass loss rate of the concrete. The test shows that there is a linear relationship between the concrete's relative dynamic elastic modulus and the increasing number of freezing-thawing cycles; the mass loss rate, however, varies with the water-cement ratio and displays different tendency of changes in the initial phase of the cycle, but the mass is decreased in the later phase. Besides, combining with the application, the writer will simulate the concrete's freezing-thawing process under actual operation conditions with the standard test data, in order to offer the presumption model of freezing-thawing durability and predict the residual freezing-thawing life of the concrete, thus providing theoretical basis for the structure's maintenance, repair, and dismantlement.

Scale variance is highly sensitive to multi-scale patterns of variables, which is advantageous in identifying spatial hierarchy and characteristic scale(s). However, the significance of peak(s) in scale variance cannot be statistically tested, and different spatial patterns may be obtained when different zoning systems are used to calculate scale variance. To address these two problems, this study compared the scale levels with peaks in scale variance and the scale levels at which there were breaks in the nature of spatial autocorrelation as identified by shifts in Moran's I scalogram. The estimates for three simulated landscapes showed that accordance between scale levels identified employing the two methods can be used to evaluate the significance of peaks in scale variance and choose a more reasonable zoning system. The approach of scale variance analysis coupled with Moran's I scalogram was also applied to the Xilin River Basin of Inner Mongolia, China. The most vital characteristic scale (64 × 32 km) identified for the growing-season net ecosystem productivity (NEP) of the basin was validated by other spatial pattern analysis methods such as semi-variogram, Moran's I correlogram, and wavelet variance analyses, and the directionality of the chosen zoning systems was found to be similar to the orientation of actual dominant vegetation type patches. The results demonstrate that Moran's I scalogram can be used to improve the interpretation of the results of scale variance analysis and increase the reliability of scale variance analysis for landscapes having a repetitive patch pattern or gradient variation and that the proposed approach is suitable for identifying the hierarchy and the characteristic scales of patterns or processes. In summary, this study used a simple approach to solve two problems in scale variance analysis, thereby improving the methodology and enhancing the theoretical basis of multi-scale analysis.

In this paper, we took lathe as the research object, and established an active vibration control system model based on neural network AVC (Active Vibration Control) system, and the Matlab simulation results showed that the AVC system can reduce vibration effectively and improve the lathe’s accuracy.

In this paper, we report the synthesis of the bifunctional Fe3O4@SiO2@Eu-polyoxometalates particles. The magnetite nanoparticles (Fe3O4) homogeneously coated with silica spheres prepared with the Stöber method. The so-obtained Fe3O4@SiO2 core/shell particles were modified by 3-aminopropyltriethoxysilane and finally grafted with the luminescent Europium -polyoxometalates. The core-shell particles were characterized by scanning electron microscopy, transmission electron microscopy, FT-IR, UV, magnetism and luminescence spectroscopy. The results indicated that the core-shell particles show both interesting luminescence and magnetic properties.

To obtain an ultralow surface reflectance and reach broadband antireflection effects,in this paper, silicon nanowires (SiNWs) layer has been fabricated by low-cost and easy-made silver-assisted etching techniques.The morphologies, reflectance and surface recombination of the samples were separately characterized. The ultralow reflectance below 3% from 300 to 800 nm under normal incidence has been realized in the case of ~ 1 μm long SiNWs whose geometry structures approximate to multi-layer gratings stack and the refractive index gradually increases from the top to the bottom of substrate. However, surface recombination of SiNWs deteriorates due to numerous dangling bonds and residual silver. Therefore, a trade-off between antireflection effect and recombination loss is the key to the electronic device.

In order to research the harm of particle matter to human health, the TSI dust instrument, particle counter and miniature meteorological instrument were used in this paper to monitor the PM10 concentration of one typical cross road in Xi’an city. The affect factors of the PM10 concentration were also discussed. The results provided that: there is weak linear relationship between sample concentration of PM10 and wind velocity because of the complex shape of the buildings. The fine particles (10 has a significant relationship with the fine particles under high humidity conditions, while it has weak correlation with traffic flow. The fine particles from vehicle emission and the high humidity condition is the primary cause of the high PM10 concentration, while the temperature and airflow caused by the building shape affect the diffusion and distribution of the PM10.

The new calculation method of fundamental natural period of vibration for multistory and high-rise steel structure, in which semirigidity of joints between beam and column, shear deformation for the cross section and so on is considered at the same time, is presented in the paper. The lateral drift stiffness of column in steel structure and inter-story stiffness of steel structure, which joints semirigidity, shear deformation and effects for steel structure is simultaneously considered, is derived in the paper. General expression for stability function considered shear deformation of the cross section for beam-column members is put forward.The approach is relatively simple and more practical. It can be referred to steel structural design.

TiC/C composite fibers were prepared by vapor phase titanizing of the regular carbon fibers via chemical vapor deposition (CVD). The carbon fibers were titanized from the surface of the fiber to the core. Scanning electron microscope (SEM) and X-ray diffraction (XRD) were applied to characterize the morphology and structure of the TiC/C composite fibers. The influences of CVD reaction conditions such as temperature and reaction time on the TiC particle size and the thickness of the deposited layer were investigated. Higher temperature and longer time resulted in the growth of bigger size of the TiC crystal particles, and the particle uniformity was also decreased.

Locomotion in immature animals is often inflexible, but gradually acquires versatility to enable animals to maneuver efficiently through their environment. Locomotor activity in adults is produced by complex spinal cord networks that develop from simpler precursors. How does complexity and plasticity emerge during development to bestow flexibility upon motor behavior? And how does this complexity map onto the peripheral innervation fields of motorneurons during development? We show in postembryonic Xenopus laevis frog tadpoles that swim motorneurons initially form a homogenous pool discharging single action potential per swim cycle and innervating most of the dorsoventral extent of the swimming muscles. However, during early larval life, in the prelude to a free-swimming existence, the innervation fields of motorneurons become restricted to a more limited sector of each muscle block, with individual motorneurons reaching predominantly ventral, medial, or dorsal regions. Larval motorneurons then can also discharge multiple action potentials in each cycle of swimming and differentiate in terms of their firing reliability during swimming into relatively high-, medium-, or low-probability members. Many motorneurons fall silent during swimming but can be recruited with increasing locomotor frequency and intensity. Each region of the myotome is served by motorneurons spanning the full range of firing probabilities. This unfolding developmental plan, which occurs in the absence of movement, probably equips the organism with the neuronal substrate to bend, pitch, roll, and accelerate during swimming in ways that will be important for survival during the period of free-swimming larval life that ensues.

It is well documented that S100A4 is upregulated in a large amount of invasive tumors and plays a pivotal role in tumor invasion and metastasis. However, the precise role and mechanism S100A4 exerts in the invasion and metastasis of esophageal squamous cell carcinoma (ESCC) have not been fully elucidated to date. Our data demonstrated that S100A4 was overexpressed in human ESCC tissues, especially in ESCC with poor differentiation, deep invasion and lymph node metastasis. Subsequently, the knockdown of S100A4 by RNAi in ESCC cell line (EC-1) could reduce cell invasion, metastasis and proliferation ability in vitro. Most importantly, S100A4 regulated MMP-2 positively and E-cadherin negatively in vivo and in vitro to some extent. Our results suggest that S100A4 is an important factor in the invasion, metastasis and proliferation of ESCC and may control invasion and metastasis at least in part through the regulation of MMP-2 and E-cadherin activity. S100A4 may serve as a biomarker for progression of ESCC and a potential molecular target for biotherapy of ESCC.

A new approach, which is suitable for analyzing steel frames-reinforced concrete shear wall hybrid structure considered the semirigid connection for beam and column in horizontal load, is presented. The new simplified method considered the semirigid connection for beam and column in hybrid structure is established. The inter-story drift stiffness of steel frames considered the semirigid connection of beam-column in hybrid structure is derived.The traditional continuum method used in RC frames-shear wall structure is expand to steel frames-reinforced concrete shear wall hybrid structure in the paper.The numerical examples of considered the semirigid connection for beam and column in hybrid structure are analysed. The analysis results show that the proposed method is suitable for adoption in practice.

The elimination process of systemically administered small interfering RNA (siRNA) was investigated by using siRNA labeled with an infrared fluorescent dye. A novel siRNA elimination pathway was identified. In this pathway, liver-enriched siRNA is secreted into the gallbladder and then emptied into the intestine. Blocking this pathway resulted in the absence of siRNA fluorescence within the intestine, with greatly enhanced siRNA accumulation in liver and gallbladder at the same time. Furthermore, we demonstrated that delivery carriers play an essential role in siRNA distribution and elimination, highlighting their importance in siRNA therapeutics.

Based on the theoretical analysis of the dynamic parameters of multi-DOF complex structures, it is shown that the optimum TMD parameters under the harmonic base excitation are not the exact optimization for seismic protection, whose main reason is that the optimum damping ratio of TMD for seismic protection is obviously lower than that under the harmonic base excitation. In this paper, an effective TMD design method is developed to control the seismic responses of many-degree-of-freedom complex structures. The EI-Centro seismic wave is introduced as the excitations and the approach to determining the optimum TMD parameters for seismic protection is effectively solved. Then with the case to design the TMD of a series reactor, the optimum TMD parameters for seismic protection are obtained. Its result proves that the designed TMD is able to reduce the seismic responses of the series reactor significantly, and this approach can provide a reference for the TMD design for seismic protection of other multi-DOF structures.

Double-stranded small interfering RNAs (siRNAs) are important modulators of biological processes and hold great promise for therapeutic applications. However, serum processing of synthetic siRNAs is still largely unknown. To address this issue, serum degradation assays of 125 siRNAs were first performed in this study. Four siRNA categories of distinct serum stability were identified, including a group of siRNAs that were stable in their native form for both in vitro and in vivo assays. Fine mapping of the cleavage events occurring in serum treatment demonstrated that most occurred at two vulnerable sites, leading to a speculation that rational modification of these sites might protect most siRNAs from serum degradation. For proof of concept, an exhaustive siRNA modification study was performed. In addition to the consistent stabilization pattern revealed at these sites, our study further showed that a single modification made at the cleavage site stabilized the siRNAs to a large extent, highlighting the importance of these sites in siRNA degradation. In summary, the present study provided a comprehensive picture of serum processing of siRNA as well as a starting point for a rational siRNA modification strategy, both of which are of great importance to in vivo and therapeutic applications of siRNA.

Four novel amino-functionalized ionic liquids were prepared with high yield (80%-90%) in a simple, straightforward, one-step synthetic method; their structures were characterized by IR, UV, and NMR, their important physical and chemical properties have been detected. According to the research of their application in absorbing SO2, these ionic liquids can act as promising perfect adsorbents with the advantages of high absorption efficiency (1.06-2.50 of the MR ratio), with high desorption efficiency of 90%-100%. In addition, it was found that these ionic liquids could be reused without significant loss of reactivity; these ionic liquids were valuable for academic and industrial application.

A systematic investigation on the morphology development of polyvinylidene fluoride hollow fiber membrane made using various N-methyl-2-pyrrolidone (NMP) aqueous solutions as an inner coagulant was carried out. The cross-sectional and inner surface morphology were analyzed with scanning electronic microscopy (SEM). It is found that with increase on NMP concentration, the morphology of the resultant membranes gradually shifted from a double-skin to a single-skin structure. When 40.0 ∼ 55.0 wt.% NMP solution was used, some unexpected macrovoids near the inner region were observed. This special morphology feature was attributed to the reduced solidification rate of the inner surface as a result of increase on NMP concentration, which sharply weakened the inner skin strength. While the existence of centralized stress formed in the phase inversion process, such as shrinkage stress from syneresis, resulted in fractured points in the nascent skin surface that finally made it difficult to maintain a uniform structure. Investigations on effects of the dope flow rate and the bore fluid velocity on the morphology of PVDF fiber membranes experimentally confirmed the suggestion. Three model membranes with double skins, single skin and single skin with macrovoids structures, respectively, were used to test their permeation performance in a CO2 membrane contactor system. The experimental results show the membranes without an inner skin present higher permeability and lower mass transfer resistance than the membrane with a double skin structure. © 2010 Wiley Periodicals, Inc. Journal of Applied Polymer Science, 2010

Summary The cytosolic DNA sensor cGAS recognizes viral DNA and synthesizes the second messenger cGAMP upon viral infection. cGAMP binds to the adaptor protein MITA/STING to activate downstream signaling events, leading to induction of type I interferons (IFNs) and antiviral effector genes. Here we identify the human cytomegalovirus (HCMV) protein UL31 as an inhibitor of cGAS. UL31 interacts directly with cGAS and disassociates DNA from cGAS, thus inhibiting cGAS enzymatic functions and reducing cGAMP production. UL31 overexpression markedly reduces antiviral responses stimulated by cytosolic DNA, while knockdown or knockout of UL31 heightens HCMV-triggered induction of type I IFNs and downstream antiviral genes. Moreover, wild-type HCMV replicates more efficiently than UL31-deficient HCMV, a phenotype that is reversed in cGAS null cells. These results highlight the importance of cGAS in the host response to HCMV as well as an important viral strategy to evade this innate immune sensor.

Statistics based experimental designs were applied to optimize the culture medium components for enhancing phenazine-1-carboxylic acid (PCA) production by Pseudomonas sp. strain M18GQ, a gacA qscR double mutant of Pseudomonas sp. strain M18. The medium components, including soybean meal, glucose and corn steep liquor, had significant effects on PCA production based on a 25−1 fractional factorial design. The concentrations of these three significant factors were subsequently optimized using a central composite design. An optimum concentration of soybean meal 73.3 g/L, corn steep liquor 18.1 g/L, glucose 17.9 g/L, and ethanol 18.0 ml/L was obtained by response surface analysis. The predicted maximum PCA yield was as high as 4011.5 mg/L, and was confirmed by validation experiments. The double mutant M18GQ produced 4032.2 mg/L PCA, which was almost 2 to 3.3-fold that produced by either single mutant M18G and M18Q. The achieved production level is economically useful for industrial application.

Prevention of relapse is the crucial task in the maintenance treatment of schizophrenia. The investigators in this study sought to determine the duration of maintenance treatment needed with the initial therapeutic dose, in contrast to a reduced dose.In a multicenter open-label, randomized, controlled study, patients with schizophrenia who were clinically stabilized following an acute episode were randomly assigned to a no-dose-reduction group (initial optimal therapeutic dose continued throughout the study), a 4-week group (initial optimal therapeutic dose continued for 4 weeks, followed by a 50% dose reduction that was maintained until the end of the study), or a 26-week group (initial optimal therapeutic dose continued for 26 weeks, followed by a 50% dose reduction until the end of the study). All patients continued until the last recruited patient completed the 1-year follow-up.Of the 404 patients who met the entry criteria and were randomly assigned, 374 completed the study. The estimated mean time from entry to relapse was 571 days in the 4-week group, 615 days in the 26-week group, and 683 days in the no-dose-reduction group, with estimated relapse rates of 30.5%, 19.5%, and 9.4%, respectively. Patients in the no-dose-reduction group experienced greater reduction in the severity of psychotic symptoms.Patients who continued to receive the full risperidone dose used for their acute episode had fewer relapses than those who had dose reductions after 4 weeks or 26 weeks during the maintenance period. There was negligible difference in side effects among the three groups.

In the paper, the luminescent lanthanide–polyoxometalates (Na9LnW10O36, Ln = Eu, Dy, Sm, noted as LnW10) were grafted on functional Stober SiO2 ultrathin film, resulting in the formation of core–shell structured self-assembled ultrathin film. The SiO2/LnW10 films show the characteristic luminescence of lanthanide due to an efficient energy transfer in self-assembly films. Especially, the self-assembly film of SiO2/EuW10 show the strong bright red emission in UV light which can be observed by naked eyes. The luminescence behavior of the self-assembled films was studied in comparison with the corresponding solid-state complexes by means of emission and excitation spectra. The luminescence properties of lanthanide (Eu, Dy, Sm)–polyoxometalate could be affected by the formation of self-assembly films, and the electrostatic interactions and chemical graft are responsible for the difference in behavior of the luminescence. SEM pictures show that the hybrid ultrathin films of lanthanide–polyoxometalates/silica particles exhibit the regular and ordered core–shell microstructures.

The role of electrical coupling between neurons in the swimming rhythm generator of Xenopus embryos has been studied using pharmacological blockade of gap junctions. A conspicuous effect of 18β-glycyrrhetinic acid (18β-GA) and carbenoxolone, which have been shown to block electrical coupling in this preparation, was to increase the duration of ventral root bursts throughout the spinal cord during swimming. The left-right coordination, the swimming frequency and the duration of swimming episodes were not affected by concentrations of 18β-GA which significantly increased burst durations. However, the longitudinal coupling was affected such that 18β-GA led to a significant correlation between rostrocaudal delays and cycle periods, which is usually only present in older larval animals. Patch clamp recordings from spinal motoneurons tested whether gap junction blockers affect the spike timing and/or firing pattern of motoneurons during fictive swimming. In the presence of 18β-GA motoneurons continued to fire a single, but broader action potential in each cycle of swimming, and the timing of their spikes relative to the ventral root burst became more variable. 18β-GA had no detectable effect on the resting membrane potential of motoneurons, but led to a significant increase in input resistance, consistent with the block of gap junctions. This effect did not result in increased firing during swimming, despite the fact that multiple spikes can occur in response to current injection. Applications of 18β-GA at larval stage 42 had no discernible effect on locomotion. The results, which suggest that electrical coupling primarily functions to synchronize activity in synergistic motoneurons during embryo swimming, are discussed in the context of motor system development.

The hexon protein of human adenovirus (HAdV) processes type-specific B-cell neutralizing epitopes. We developed a new effective, reliable approach to map these epitopes on hexon protein of HAdVs. A three-dimensional (3D) model of the HAdV3 hexon was obtained by homology modeling and refined by molecular mechanics and molecular dynamics simulations. A modified evolutionary trace (ET) analysis called reverse ET (RET) was used to predict the type-specific B-cell neutralizing epitopes. An epitope-screening algorithm based on analyzing the solvent accessibility surface (SAS) area from the 3D model and calculation of sites homology using RET was designed and implemented in the BioPerl script language. Five epitope polypeptide segments were predicted and mapped onto the 3D model. Finally five polypeptides were synthesized and the predicted epitopes were identified by enzyme-linked immunosorbent assay (ELISA) and Neutralization Test (NT). It was found that the type-specific neutralizing epitopes of HAdV3 are located at the top surface of hexon tower regions (residue numbers: 135–146, 169–178, 237–251, 262–272, 420–434). This work is of great significance to the molecular design of a multivalent HAdVs vaccine.

A methanolic extract of propolis obtained in Myanmar was found to inhibit PANC-1 human pancreatic cancer cells preferentially under nutrient-deprived conditions (NDM), with a PC(50) value of 9.3 microg/mL. Bioactivity-guided fractionation of the extract led to the isolation of two new cycloartane-type triterpenes, (22Z,24E)-3-oxocycloart-22,24-dien-26-oic acid (1) and (24E)-3-oxo-27,28-dihydroxycycloart-24-en-26-oic acid (2), together with 13 cycloartanes (3-13) and four known prenylated flavanones (14-17). Among these, compound 1 exhibited the most potent preferential cytotoxicity (PC(50) 4.3 microM) in a concentration- and time-dependent manner. Furthermore, 1 induced apoptosis-like morphological changes of PANC-1 cells within 24 h of treatment.

A novel biological sample clean-up procedure has been developed for the determination of phosphorothioate oligodeoxynucleotides (PS-ODNs) and derived metabolites in biological fluids (plasma, urine and bile) and in tissues and feces from mice and rats. This method uses a one-step C18 solid-phase extraction (SPE) for biological matrix removal, and it uses capillary gel electrophoresis (CGE) for analyte detection. The assay is specific, and its linearity is superb (r0.99) for IV-AS (a 13-mer PS-ODN) and PS19 (a 19-mer PS-ODN) in a variety of biological matrices. For both IV-AS and PS19, the precision, accuracy and absolute recovery values were found to be20%, +/-20% and 80-120%, respectively. The LODs of IV-AS and PS19 were 0.6 mg/l for plasma, 0.8 mg/l for rat urine and bile, 6 microg/g for rat tissues, and 10 microg/g for rat feces, with a signal-to-noise ratio of 3 (S/N=3). This method has been successfully applied to the analysis and quantitation of PS-ODNs in various biological samples arising from preclinical pharmacokinetic studies.

From focal mechanism solutions of the earthquakes in the northern part of North China during the period of 2002∼2006, the directions of principal stress axes in 4 stress sub-districts are analyzed using a grid test method. The characteristic of present crustal stress directions is discussed. Based on this result and on the focal mechanism solutions calculated for some events in the period of 1977∼1998, in combination with some other study results, the temporal variation of present crustal stress directions in the northern part of North China is investigated. The results confirm that the direction of crustal principal stress in some regions had somewhat rotated after the 1976 Tangshan M7.8 earthquake. The mean P axes of the focal mechanism solutions rotated clockwise not only in Tangshan sub-district, but also in Beijing and Xingtai sub-districts after the Tangshan earthquake. In Beijing and Xingtai sub-districts the orientations of principal stress axes in the period of 2002∼2006 are consistent with that before the Tangshan earthquake, implying that the stress orientations has rotated back to the state before the Tangshan earthquake in these two sub-districts. The directions of the mean P axes are nearly E-W in Tangshan sub-district since the M7.8 earthquake. The present stress field in the sub-district northwest to Beijing, or in the western part of the Zhangjiakou-Bohai fault zone, is relatively stable during the time period concerned in this study. Because of the limitation of data, this paper only states a possible variation of stress field in the northern part of North China in the recent decades.