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In recent years, mode division multiplexing (MDM) which use the few mode fibers(FMF) as transmission link has attracted widespread attention and many MDM systems were demonstrated. However, some drawbacks arising with MDM cannot be ignored, such as mode coupling, differential mode group delay(DMGD) and etc. Fortunately, many of them can be conveniently mitigated by digital equalization at a low cost. In order to solve the problems of slow convergence speed and poor equalization effect of digital equalizer in the polarization division multiplexed (PDM)-MDM system (PDM-MDM), a modified partitioned frequency domain equalization algorithm is proposed in this paper. In the proposed algorithm, the filter length is divided into several partitions and consequently each partitions’ average power model was rebuilt with its individual length. The performance of 3-LP MDM system is investigated in terms of convergence speed, constellation diagram and symbol error rate(SER). From the simulation results, the modified partitioned frequency domain algorithm can get better SER performance by about an order of magnitude and improve the convergence rate by about 10 % compared to traditional algorithm.

Different modes of surface waves possess different phase velocities for each wavelength, which reflects the layer information of different depths. Penetrating depth of surface wave data is significant to determine stratigraphic models and invert their velocity structures. Instead of ray theory, we use the sensitivity kernels to investigate the relationship between multimode wavelengths and penetrating depth for a layered model based on the adjoint wave equation. We use linear Radon transform to perform Rayleigh-wave multimode separation and reconstruction. The results confirm that longer wavelength components are sensitive to deeper layers. Different modes of surface waves are sensitive to different depths. The kernels in HVL (high-velocity-layer model) and LVL (low-velocity-layer model) suggest that the velocity anomaly layer has a shielding effect on sensitivity penetrating. Rayleigh waves are insensitive to the layers beneath a velocity anomaly layer and the HVL itself.

Scope Alzheimer's disease (AD) is the most prevalent form of dementia in the aging population; however, no effective therapy has been established. It has been previously demonstrated that daily intake of hydroxytyrosol (HT), a polyphenol in olive oil, at a daily dietary level mildly improves cognition in AD mice. In the present study, HT acetate (HT-ac), which is a natural derivative of HT in olive oil that exhibits better bioactivity than HT improves cognition. Methods and results HT-ac to APP/PS1 is orally administered to transgenic mice and used Aβ-treated neuronal cultures to explore the neuroprotective effects of HT-ac in preventing AD progression. It is found that HT-ac remarkably improved the escape latency, escape distance, and the number of platform crossings of AD mice in the water maze test by ameliorating neuronal apoptosis and decreasing inflammatory cytokine levels. It is further demonstrated that HT-ac stimulated the transcription of ERβ and enhanced neuronal viability and electrophysiological activity in primary neurons but that these beneficial effects of HT-ac are abolished upon ERβ deficiency. Conclusions This study suggests that as the bioactive component of olive oil, HT-ac is a promising neuroprotective nutrient that may be used to alleviate AD-related cognitive dysfunction.

In this study, we propose an approach for determining the geopotential difference using high-frequency-stability microwave links between satellite and ground station based on Doppler cancellation system. Suppose a satellite and a ground station are equipped with precise optical-atomic clocks (OACs) and oscillators. The ground oscillator emits a signal with frequency f a towards the satellite and the satellite receiver (connected with the satellite oscillator) receives this signal with frequency f b which contains the gravitational frequency shift effect and other signals and noises. After receiving this signal, the satellite oscillator transmits and emits, respectively, two signals with frequencies f b and f c towards the ground station. Via Doppler cancellation technique, the geopotential difference between the satellite and the ground station can be determined based on gravitational frequency shift equation by a combination of these three frequencies. For arbitrary two stations on ground, based on similar procedures as described above, we may determine the geopotential difference between these two stations via a satellite. Our analysis shows that the accuracy can reach 1 m 2 s − 2 based on the clocks’ inaccuracy of about 10 −17 (s s −1 ) level. Since OACs with instability around 10 −18 in several hours and inaccuracy around 10 −18 level have been generated in laboratory, the proposed approach may have prospective applications in geoscience, and especially, based on this approach a unified world height system could be realized with one-centimetre level accuracy in the near future.

Researches on the southeastern Tibetan Plateau provide important insights into the tectonic evolution of the Tibetan Plateau. In this study, we have constructed a high-resolution 3D shear-wave velocity model through joint inversion of receiver functions and surface wave dispersion data. The crustal thickness and Poisson’s ratio models are first determined by H–k stacking of receiver functions. The crustal thickness changes from 30 km in the south to 62 km in the north, presenting strong lateral variations. The fundamental mode of Rayleigh wave dispersion data spanning periods from 8 to 65 s were then jointly used to constraint the absolute shear-wave velocity. The shear-wave velocity structure shows lateral variations. There are low velocity zones distributed in the crust and upper mantle. Two continuously distributed low velocity zones are clearly presented in the middle-to-lower crust, which extend from north toward southeast and southwest, respectively, joining together in southern Yunnan. In this study, we deduced the migration model of soft materials in middle-to-lower crust in southeastern Tibetan Plateau, which explains that the resistance from Sichuan Basin separates the flowing materials from Tibetan Plateau into southeast and northwest branches. They flow along the west margin of Sichuan Basin and then extrude out from northeastern and southeastern Tibetan Plateau respectively. The southeast branch is blocked and cannot flow in the entire crust. It is limited in a certain range of depths and channels. The two low velocity zones in this study possibly present two flow channels of the middle-to-lower crustal materials extruded from the Tibetan Plateau.

The plant-specific sucrose nonfermenting 1-related protein kinase 2 (SnRK2) family is considered an important regulator of plant responses to abiotic stresses such as drought, cold, salinity, and nutrition deficiency. However, little information is available on how SnRK2s regulate sulfur deprivation responses in Arabidopsis. Large-scale production of SnRK2 kinases in vitro can help to elucidate the biochemical properties and physiological functions of this protein family. However, heterogenous expression of SnRK2s usually leads to inactive proteins. In this study, we expressed a recombinant Arabidopsis SnRK2.1 in a modified E. coli cell-free system, which combined two kinds of extracts allowing for a convenient and affordable protein preparation. The recombinant SnRK2.1 was produced in large-scale and the autophosphorylation activity of purified SnRK2.1 was characterized, allowing for further biochemical and substrate binding analysis in sulfur signaling. The application of this improved E. coli cell-free system provides us a promising and convenient platform to enhance expression of the target proteins economically.

SUMMARY Seafloor hydrothermal sulfide deposits occurring at plate boundaries and convergent plate boundaries, are mainly concentrated in extensional tectonic belt with abundant fault structure, which is always correlated with the severe potential field signals changes. Considering the common magnetic anomaly components cannot reflect the field sources correctly as magnetic field around the ocean ridges is extremely infected by the residual magnetism, based on the obvious superiority of the magnitude magnetic transforms (MMTs) centricity and low dependence on the magnetization vector direction, we used the MMTs for geological boundaries identification. We improved the Tilt derivative method to indentify the boundaries of the geological structure on the basis of both the MMTs E and R, and find that the MMTs E combined with the improved Tilt derivative method performs better . We applicant this method in the 49° E zone (48E52E ，-39S-37S) of the Southwest India Ridge (SWIR), with the help of the 2-arc minute high resolution magnetic model EMAG2, the fault system distribution of the study area was obtained and described primarily.

In this paper, the squint mode multi-channel (MC) synthetic aperture radar (SAR) with hybrid baseline and fluctuant terrain is proposed and studied for high-resolution and wide-swath (HRWS) imaging. During the imaging process, due to the cross-track baseline and fluctuant terrain, the azimuth signal reconstruction is the kernel problem for this imaging mode. To deal with this problem, in this paper a robust azimuth signal reconstruction approach is proposed, where terrain elevation of scene is considered. At first, the pre-processing of the linear range cell migration correction (RCMC) and topography-independent phase compensation is implemented in the azimuth time domain. After that, combining the azimuth echo signal characteristics, the local polynomial Fourier transform (LPFT) is utilized to obtain the coarse-focused SAR image. Then, based on joint pixel pair vector and robust Capon beamforming (RCB), a Doppler ambiguity suppression approach is proposed to reconstruct the Doppler ambiguity-free azimuth signal in LPFT frequency domain, during which the influence of the cross-track baseline component and fluctuant terrain is eliminated using the coarse digital elevation model (DEM) for the imaging scene. At last, the chirp scaling imaging algorithm is utilized to focus the SAR image. The effectiveness of the proposed imaging approach is demonstrated via simulated and real measured squint mode MC-HRWS SAR data.

Earned value management (EVM) emerged in the United States in the 1960s[1]. It is used as an important standard of project cost management and progress management. The focus of earned value is to accurately measure the specific plan and actual performance of a project, which can accurately predicts the final cost and schedule results of the project. Earned value is based on the integration of various means of project management, so that the real cost performance of the project can be reflected, which is not achieved by other project management technologies. Based on the actual B2B project of ABCD company, this paper studies the application of earned value in practice.

Because of the limitations of Earned Value Management (EVM), there are great defects in managing software progress. Although Earned Schedule (ES) improves EVM, it is not reliable to utilize cost data to measure software progress. In 2014, Earned Duration Management (EDM), which is a new measurement method, was introduced. In this paper, via a practical case, the EDM method is used to measure the software progress.

Powdery mildew (PM) caused by Blumeria graminis f. sp. tritici is one of the most economically important wheat diseases in China. Almost all commercially cultivated wheat varieties are susceptible to PM disease, especially the commercial spring wheat varieties grown in the Northwestern region of China. Pm21 was identified as one of the most effective resistance gene to PM in China, and many wheat varieties carrying Pm21 have been developed and released in different areas since 2010. In this study, 3 PM susceptible spring wheat varieties (Ningchun4, Ningchun47, and Ningchun50) were crossed with a PM resistant line CB037 (carrying Pm21) which is a wheat-Dasypyrum villosum T6AL·6V#2S translocation line, and were then backcrossed with the three spring varieties as recurrent parents, combining the disease test with molecular marker selection. After five times of backcrossing and four generations of selfing, nine advanced lines with strong PM resistance and good agronomic traits (plant height, grains per spike, one thousand kernels weight, and yield) were developed. These lines were further evaluated using the analyses of Pm21-specific markers and genomic in situ hybridization (GISH), and tested in a field trial for agronomic traits including grain yield. Results indicated that all the improved lines were similar to their corresponding recurrent varieties except an obvious difference in plant height. Lines NZ39, NZ42, and NZ46 showed an increase in grain yield (by 1.70–9.38%) and one thousand kernel weight (by 0.4–7.3 g). Compared to their respective recurrent parents, lines NZ41 and NZ46 showed improved bread-making quality, displaying optimal application potential in wheat production.

L 1 adaptive control is a new control methodology developed in recent years. This paper introduces the discrete integral of the uncertainty to the standard piecewise constant adaptive law of the L 1 adaptive output feedback control. The modified adaptive law can guarantee better transient and steady target tracking performance compared with the standard adaptive law. A global nonlinear optimization process is carried out to obtain the sub-optimal filter design for the L 1 adaptive output feedback controller to maximize the performance index. With these design technique, an augmented L 1 adaptive control structure is applied to the temperature control of a wind tunnel. The simulation results and analysis demonstrate the effectiveness of the proposed control architecture.

The Tengchong volcanic area is located in the southeastern margin of the collision zone between the Indian and Eurasian Plates. It is one of the youngest intraplate volcano groups in mainland China. Imaging the S-wave velocity structure of the crustal and uppermost mantle beneath the Tengchong volcanic area is an important means of improving our understanding of its volcanic activity and seismicity. In this study, we analyze teleseismic data from nine broadband seismic stations in the Tengchong Earthquake Monitoring Network. We then image the crustal and uppermost mantle S-wave velocity structure by joint analysis of receiver functions and surface-wave dispersion. The results reveal widely distributed low-velocity zones. We find four possible magma chambers in the upper-to-middle crust and one in the uppermost mantle. The chamber in the uppermost mantle locates in the depth range from ~ 55 to ~ 70 km. The four magma chambers in the crust occur at different depths, ranging from the depth of ~ 7 to ~ 25 km in general. They may be the heat sources for the high geothermal activity at the surface. Based on the fine crustal and uppermost mantle S-wave velocity structure, we propose a model for the distribution of the magma chambers.

Inversion of receiver functions is commonly used to recover the S-wave velocity structure beneath seismic stations. Traditional approaches are based on deconvolved waveforms, where the horizontal component of P-wave seismograms is deconvolved by the vertical component. Deconvolution of noisy seismograms is a numerically unstable process that needs to be stabilized by regularization parameters. This biases noise statistics, making it difficult to estimate uncertainties in observed receiver functions for Bayesian inference. This study proposes a method to directly invert observed radial waveforms and to better account for data noise in a Bayesian formulation. We illustrate its feasibility with two synthetic tests having different types of noises added to seismograms. Then, a real site application is performed to obtain the 1-D S-wave velocity structure beneath a seismic station located in the Tengchong volcanic area, Southwestern China. Surface wave dispersion measurements spanning periods from 8 to 65 s are jointly inverted with P waveforms. The results show a complex S-wave velocity structure, as two low velocity zones are observed in the crust and uppermost mantle, suggesting the existence of magma chambers, or zones of partial melt. The upper magma chambers may be the heart source that cause the thermal activity on the surface.

The present study aims to reveal the recovering period of the postseismic fluid pressure in fault zone, offering an insight into earthquake recurrence. Numerical modeling is performed based on a 2D simple layered fault-valve model to simulate the fluid activities within the earthquake fault. In order to demonstrate the features of postseismic fluid pressure in natural state, the interference of tectonic movements is not considered. The recovering period of postseismic fluid pressure includes a suddenchanging period and a much longer fluctuating period. Modeling results show that fault permeability and porosity are sensitive parameters and reversely proportional to the recovering period of the fluid pressure in earthquake fault zone. When the permeability reduces from 10-15 to 10-18 m2, the recovering period increases from 400 to 2 000 yrs, correspondently. The upper and lower fluid pressures are separated by the valve seal, causing their fluctuations in opposite tendencies.

Lushan Earthquake (~M w 6.6) occurred in Sichuan Province of China on 20 April 2013, was the largest earthquake in Longmenshan fault belt since 2008 Wenchuan Earthquake. To better understand its rupture pattern, we focused on the influences of fault parameters on fault slips and performed fault slip inversion using Akaike’s Bayesian Information Criterion (ABIC) method. Based on GPS coseismic data, our inverted results showed that the fault slip was mainly confined at depths. The maximum slip amplitude is about 0.7 m, and the scalar seismic moment is about 9.47×1018 N·m. Slip pattern reveals that the earthquake occurred on the thrust fault with large dip-slip and small strike-slip, such a simple fault slip represents no second sub-event occurred. The Coulomb stress changes (ΔCFF) matched the most aftershocks with negative anomalies. The inverted results demonstrated that the source parameters have significant impacts on fault slip distribution, especially on the slip direction and maximum displacement.

This paper describes a clutter suppression approach and the corresponding moving target imaging algorithm for a multichannel in azimuth high-resolution and wide-swath (MC-HRWS) synthetic aperture radar (SAR) system. Incorporated with digital beamforming processing, MC-HRWS SAR systems are able to suppress the Doppler ambiguities to allow for HRWS SAR imaging and null the clutter directions to suppress clutter for ground moving target indication. In this paper, the degrees of freedom in azimuth for the multichannel SAR systems are employed to implement clutter suppression. First, the clutter and moving target echoes are transformed into the range compression and azimuth chirp Fourier transform frequency domain, i.e., coarse-focused images formation, when the clutter echoes are with azimuth Doppler ambiguity. Considering that moving targets are sparse in the imaging scene and that there is a difference between clutter and a moving target in the spatial domain, a series of spatial domain filters are constructed to extract moving target echoes. Then, using an extracted moving target echo, two groups of signals are formed, and slant-range velocity of a moving target can be estimated based on baseband Doppler centroid estimation algorithm and multilook cross-correlation Doppler centroid ambiguity number resolving approach. After the linear range cell migration correction and azimuth focus processing, a well-focused moving target image can be obtained. In addition, the proposed clutter suppression and imaging approach is not only adapted for uniformly displaced phase center sampling but also for the nonuniform sampling cases. Some simulation experiments are taken to demonstrate our proposed algorithms. Finally, some real measured data results are presented to validate the theoretical investigations and the proposed approaches.

Mode division multiplexed(MDM) in few mode fibers has got attraction due to its potential to achieve ultra-high capacity beyond the nonlinear Shannon limit of the single mode fiber. However, the effect of dispersion, mode coupling and differential group delay on optical signals cannot be ignored, thus equalizing these impairments are required in MDM system. In this paper, a partitioned modified frequency domain least mean square(PFDLMS) algorithm is proposed for the digital dispersion equalizer of polarization division multiplexing(PDM)-MDM coherent system. The simulation results show that the proposed algorithm can improve the convergence speed and get a great equalization performance.

A joint timing offset (TO) and frequency offset (FO) estimation method based on Radon-Wigner transform (RWT) is first proposed for coherent optical orthogonal frequency-division multiplexing (CO-OFDM) systems. The result shows that the timing and frequency synchronization performance of the proposed method are both better than the Schmidl & Cox method and fractional Fourier transform (FrFT) algorithm in a poor OSNR condition.

For high-resolution wide-swath (HRWS) SAR based on multiple receive apertures in azimuth, this paper proposes a novel imaging approach for moving targets. This approach utilizes the wide bandwidth characteristics of the transmitted signal (multiple wavelengths) to estimate the moving target velocity. First, this paper explains that there is a phase mismatch (PM) between azimuth channels for the echo of a moving target, which depends on range frequency. In order to correct the PM, an algorithm based on local maximum-likelihood minimum entropy is proposed. The linear dependence of the PM on range frequency is employed to estimate the target velocity. Second, after the signal reconstruction in Doppler frequency and the compensation of the PM for a moving target, the estimated target velocity is utilized to implement the linear range cell migration correction and the Doppler centroid shifting. Then, the quadratic range cell migration is corrected by the keystone processing. After that, the focused moving target image can be obtained using the existing azimuth focusing approaches. Theoretical analysis shows that no interpolation is needed. The effectiveness of the imaging algorithm for moving targets is demonstrated via simulated and real measured ship HRWS ScanSAR data.

An improved method based on a genetic algorithm (GA) is developed to design a broadband electrical impedance matching network for piezoelectric ultrasound transducer. A key feature of the new method is that it can optimize both the topology of the matching network and perform optimization on the components. The main idea of this method is to find the optimal matching network in a set of candidate topologies. Some successful experiences of classical algorithms are absorbed to limit the size of the set of candidate topologies and greatly simplify the calculation process. Both binary-coded GA and real-coded GA are used for topology optimization and components optimization, respectively. Some calculation strategies, such as elitist strategy and clearing niche method, are adopted to make sure that the algorithm can converge to the global optimal result. Simulation and experimental results prove that matching networks with better performance might be achieved by this improved method.

The analytical dispersion and waveform solutions of Rayleigh surface wave for the Biot fluid-saturated model are obtained at low frequencies for a homogeneous half space. The equivalent solution is also obtained by the equivalent-viscoelastic representation of the fluid-saturated model based on a single viscoelastic element for each wave modulus. The effective characteristics of the validations and limitations for the equivalent-viscoelastic model are analyzed by comparison of the numerical solutions of the fluid-saturated model and the equivalent model for the surface wave propagations. Our calculations show that the free boundary effects on the frequency dependent dispersion and time dependent dynamical waveforms of the surface wave in the Biot model are well fitted in a relative narrow low frequency band by the Zener elements in case of the frequency is much lower than the critical frequency f c of the porous material. The effective characteristics for air filled cases with a higher f c show a better result. Furthermore, if the critical frequency f c is low, always with high permeability κ under near surface condition, at low frequencies (e.g. the seismic frequency band

Three-dimensional transient responses of porous media under moving surface impulses of finite frequency components are theoretically studied. We discuss three free-surface stiffness conditions, such as fully permeable—‘open pore’, fully impermeable—‘closed pore’, and partially permeable boundaries, that are not explicitly discussed before. The transient responses of the solid vertical displacement and the pore fluid pressure triggered by the moving impulses on the surface are particularly investigated in different typical surface stiffness, moving impulse velocities, material permeabilities and impulse peak frequencies. It is concluded that the R1 surface wave carries the strongest energy as that for stationary source configurations. Moreover, it is more sensitive to surface stiffness condition than body waves represented in the responses of the corresponding wave forms of obvious different amplitudes and arrival time. Furthermore, the apparent velocity of the moving impulse pointing toward the fixed receiver may cause ‘blue shift’ in frequency. The higher velocity triggers more obvious frequency shift. For the moving impulse of low peak frequency, this shift becomes much serious. The lateral velocity of the moving impulse to the receiver may also twist the received wave forms, especially for the impulse of low peak frequency.

Alzheimer's disease (AD) is considered a multifactorial disease that affects the central nervous system and periphery. A decline in brain glucose metabolism is an early feature of AD and is accompanied by a phenotypic shift from aerobic glycolysis to ketogenesis. The liver is responsible for the generation of the ketone body. However, the mechanism that underlies hepatic ketogenesis in AD remains unclear. Here, we investigated hepatic ketogenesis during the early stage of AD pathogenesis in amyloid precursor protein (APP

High-resolution and wide-swath (HRWS) synthetic aperture radar (SAR) is an essential tool for modern remote sensing. To effectively deal with the contradiction problem between high-resolution and low pulse repetition frequency and obtain an HRWS SAR image, a multi-channel in azimuth SAR system has been adopted in the literature. However, the performance of the Doppler ambiguity suppression via digital beam forming processing suffers the losses from the channel mismatch. In this paper, a robust channel-calibration algorithm based on weighted minimum entropy is proposed for the multi-channel in azimuth HRWS SAR imaging. The proposed algorithm is implemented by a two-step process. 1) The timing uncertainty in each channel and most of the range-invariant channel mismatches in amplitude and phase have been corrected in the pre-processing of the coarse-compensation. 2) After the pre-processing, there is only residual range-dependent channel mismatch in phase. Then, the retrieval of the range-dependent channel mismatch in phase is achieved by a local maximum-likelihood weighted minimum entropy algorithm. The simulated multi-channel in azimuth HRWS SAR data experiment is adopted to evaluate the performance of the proposed algorithm. Then, some real measured airborne multi-channel in azimuth HRWS Scan-SAR data is used to demonstrate the effectiveness of the proposed approach.

In this letter, we discuss the problem that linear range cell walk correction in the azimuth time domain may cause space variation along the azimuth not only to the quadratic phase but also to the quadratic range cell migration (QRCM) under the conditions of high resolution and large scene along the azimuth. Moreover, an algorithm is proposed to deal with this problem. The proposed algorithm adopts the azimuth space variation filtering in the range frequency domain. In addition, the range-dependence component of QRCM is corrected by linear chirp scaling, and the unified QRCM can be corrected in the 2-D frequency domain. The proposed algorithm, without interpolation, can be easily implemented by integrating with motion compensation for image processing. Simulation and airborne strip-map real data show the accuracy and efficiency of the proposed algorithm.

Heat shock factors (HSFs) in plants regulate heat stress response by mediating expression of a set of heat shock protein (HSP) genes. In the present study, we isolated a novel heat shock gene, TaHSF3, encoding a protein of 315 amino acids in wheat. Phylogenetic analysis showed that TaHSF3 belonged to HSF class B2. Subcellular localization analysis indicated that TaHSF3 localized in nuclei. TaHSF3 was highly expressed in wheat spikes and showed intermediate expression levels in roots, stems, and leaves under normal conditions. It was highly upregulated in wheat seedlings by heat and cold and to a lesser extent by drought and NaCl and ABA treatments. Overexpression of TaHSF3 in Arabidopsis enhanced tolerance to extreme temperatures. Frequency of survival of three TaHSF3 transgenic Arabidopsis lines was 75–91 % after heat treatment and 85–95 % after freezing treatment compared to 25 and 10 %, respectively, in wild-type plants (WT). Leaf chlorophyll contents of the transformants were higher (0.52–0.67 mg/g) than WT (0.35 mg/g) after heat treatment, and the relative electrical conductivities of the transformants after freezing treatment were lower (from 17.56 to 18.6 %) than those of WT (37.5 %). The TaHSF3 gene from wheat therefore confers tolerance to extreme temperatures in transgenic Arabidopsis by activating HSPs, such as HSP70.

The plant-specific sucrose nonfermenting 1-related protein kinase 2 (SnRK2) family is considered an important regulator of plant responses to abiotic stresses such as drought, cold, salinity, and nutrition deficiency. However, little information is available on how SnRK2s regulate sulfur deprivation responses in Arabidopsis. Large-scale production of SnRK2 kinases in vitro can help to elucidate the biochemical properties and physiological functions of this protein family. However, heterogenous expression of SnRK2s usually leads to inactive proteins. In this study, we expressed a recombinant Arabidopsis SnRK2.1 in a modified E. coli cell-free system, which combined two kinds of extracts allowing for a convenient and affordable protein preparation. The recombinant SnRK2.1 was produced in large-scale and the autophosphorylation activity of purified SnRK2.1 was characterized, allowing for further biochemical and substrate binding analysis in sulfur signaling. The application of this improved E. coli cell-free system provides us a promising and convenient platform to enhance expression of the target proteins economically.

A numerical approach for free surface boundary formulation is proposed for simulation of surface waves in porous media, based on the Biot poroelastic model. A set of free surface characteristic variables for incoming and outgoing wave fields are set by domain decomposition for solid and fluid velocity and stress equations to account for the discontinuity of variables along the interface. A numerical example of a pseudospectral approach using Fourier and Chebyshev methods to compute the spatial derivatives along the horizontal and vertical directions, respectively and a splitting algorithm time solver accounting for the stiffness of the differential equations is presented to show the computional efficiency of the proposed method. In this study, we present a numerical algorithm that allows for the accurate simulation of surface wave propagation in porous media. The algorithm is based on an explicit treatment of interfaces. A decomposed domain is used for the wavefield at the interface to describe an incoming and an outgoing field for the medium based on characteristic variables that are evaluated for free surface boundary conditions (7) and has the

The efficiency of enzymatic hydrolysis of cellulose can be improved by various pretreatments of the substrate. In order to increase the efficiency of enzymatic saccharification of the wheat straw, we determined the effect of different pretreatments on the physical structure, chemical components and enzymatic saccharification of wheat straw. Our results showed that combination of grinding and sodium hydroxide (NaOH) treatment had high effect on the enzymatic hydrolysis of wheat straws. The optimal pretreatment condition was to grind the wheat straws into the sizes of 120 meshes followed by treatment with 1.0% NaOH for 1.5 h (121°C/15psi). Under this condition, the cellulose content of wheat straw was increased by 44.52%, while the content of hemicellulose and lignin was decreased by 44.15% and 42.52%, respectively. Scanning Electronic Microscopy and infrared spectrum analyses showed that significant changes occurred in the structure of wheat straws after pretreatment, which is favorable for the hydrolysis and saccharification. Cellulase produced by Penicillium waksmanii F10-2 was used to hydrolyze the pretreated wheat straw and the optimal condition was determined to be 30 h of enzymatic reaction under the temperature of 55°C, pH 5.5 and substrate concentration of 3%.

The goal of this paper is to suppress the narrowband interference (NBI) and wideband interference (WBI) in synthetic aperture radar (SAR) by using a nonparametric method. The method is based on the analysis of time-frequency characteristic of NBI and WBI from which an interference suppression filter combined with the constant false alarm rate algorithm is designed. In this approach, the short-time Fourier transform (STFT) is used to estimate the instantaneous frequency of the SAR echo data with interference. In the STFT domain, the instantaneous frequency spectrum is represented by wavelet, and then, the designed filter filters the corresponding wavelet coefficients of the interference components. In addition, this algorithm is robust to time-varying NBI and WBI. The performance of the proposed approach is evaluated by the simulated and measured data, and the effectiveness is demonstrated.

Rayleigh wave dispersion signals are significant to underground investigation. Traditionally, uniformed trace spacing is employed in surface wave surveys. In some cases, however, uneven trace spacing is often encountered because of the limitations of the site condition. In order to study the influence of uneven trace spacing on the dispersion data construction of Rayleigh waves, data acquisition is performed based on a 2.5D field layout with a linear array of geophones fixed and a mobile source. The observation direction controls the trace spacing of the measurement. The final results demonstrate that the trace nonuniformity has significant influence on the Rayleigh wave dispersion feature constructed. When the observation angle is over 45°, the dispersion image will be too distorted to extract dispersion data correctly.

The hi-energy bands in the dispersion image are usually interpreted as the true dispersion phase velocities. However, the multiple dispersion modes of Rayleigh wave in layered media stack in space, producing the effective dispersion curve and the pseudo multimode dispersion curves in dispersion image. The effective dispersion curve has the maximum energy with lower phase velocities than pseudo dispersion phase velocities, and thus is often misunderstood as the fundamental mode. Within the tolerable misfit, the effective dispersion curve can approach the true fundamental mode. Different from the true multimode dispersion curves, the pseudo multimode dispersion curves are related to the effective dispersion curve. A numerical model is adapted to simulate the true dispersion curves, effective dispersion curve, and pseudo multimode dispersion curves. Their differences and mutual relations are demonstrated.

Similar to the conventional synthetic aperture radar (SAR) imaging processing, the estimation of Doppler chirp rate is one key problem for the multi-channel in azimuth high-resolution and wide-swath (HRWS) SAR system. At the same time, the accurate estimation of baseline in azimuth is also important for the reconstruction of ambiguity-free Doppler spectrum. In this paper, based on the Map Drift algorithm and correlation function approach, a novel Doppler chirp rate estimation approach in time domain is proposed for the multichannel in azimuth HRWS SAR system. Furthermore, a baseline length in azimuth estimation algorithm is developed from the proposed Doppler chirp rate method, which is based on the correlation function between the echoes of adjective channels. The proposed approaches are successfully applied to process the real five-channel HRWS SAR echo and the good performance is demonstrated.

A numerical approach is presented for time domain staggered-grid finite difference modeling of surface waves in porous media, based on the Biot model of poroelasticity. A set of free-surface boundary conditions for solid and fluid are applied based on averaging the medium properties of the nodes along the free surface. The proposed method has higher computional efficiency than that of the previous stress imaging approach at the equivalent precision under the same spatial and temporal discretization.

In this study, soil magnetic measurements (susceptibility and hysteretic parameters) and soil hydrocarbon analyses were conducted on samples from three profiles (profiles I and II run across, and profile III runs parallel to the trend of the Jingbian gas field in the Ordos basin, central China) to determine the relationship between the magnetic anomalies (e.g., volume-specific magnetic susceptibility k) and the hydrocarbon seepage environments. The results document a strong correlation between magnetic susceptibility and soil-gas hydrocarbon concentration. Furthermore, the spatial distribution of k and hydrocarbon anomalies correlate with those of the gas field. In addition, magnetic minerals in the soils with higher susceptibility are predominantly magnetite, with little or no substitution of titanium compared to that of samples with lower susceptibility (7 105 SI [International Unit of susceptibility]). These results provide strong evidences for the formation of highly magnetic minerals in close association with hydrocarbon seepage. Recognition of such seepage-induced magnetic anomalies can be used to facilitate the exploration for oil and gas in China and elsewhere.

To elucidate the effect of gene transfected marrow stromal cell on expansion of human cord blood CD34(+) cells, a culture system was established in which FL and TPO genes were transfected into human stromal cell line HFCL. To establish gene transfected stromal cells co-culture system, cord blood CD34(+) cells were purified by using a magnetic beads sorting system. The number of all cells and the number of CD34(+) cells and CFC (CFU-GM and BFU-E) were counted in different culture systems. The results showed that in all 8 culture systems, SCF+IL-3+HFT manifested the most potent combination, with the number of total nucleated cells increasing by (893.3 +/-52.1)-fold, total progenitor cells (CFC) by (74.5 +/-5.2)-fold and CD34(+) cells by 15.7-fold. Maximal expansions of CFC and CD34(+) cells were observed at the end of the second week of culture. Within 14 days of culture, (78.1 +/- 5.5)-fold and (57.0 +/- 19.7)-fold increases in CFU-GM and BFU-E were obtained. Moreover, generation of LTC-IC from amplified CD34(+) cells within 28 days was found only in two combinations, i.e. SCF+IL-3+FL+TPO and SCF+IL-3+HFT, and there was no significant difference between these two groups statistically. These results suggest that human umbilical cord blood CD34(+) cells can be extensively expanded ex vivo by using gene transfected stromal cells along with cytokines.

An integrated geophysical survey which combines vertical seismic profile method, shallow reflection seismic method, electric sounding, soil temperature measurement and radioactive gas measurement was used to investigate Zhaoshuling landslide in the new site of Badong County and to assess the stability of the landslide. By rational use of these methods together with borehole geological profile and other geological information, the spatial distribution of the landslide body, the formations and structures within and without the landslide body were determined and the stability of the landslide was also assessed, thus making great contribution to the successful and rational investigation and assessment of the landslide.

The degree of folding of a single three-dimensional (3D) polymer configuration is a general concept associated with the pattern of interpenetrations between chain loops. In the present context, this notion applies to the state of a rigid chain, regardless

For the multi-channel in azimuth high-resolution and wide-swath (MC-HRWS) synthetic aperture radar (SAR), a novel maximum-likelihood-based Doppler centroid estimation algorithm is developed. During the estimation process, the Doppler centroid is estimated by using the maximum-likelihood approach to combine the range-frequency-variant Doppler characteristics in each channel, such as the cross-functions between neighbouring channels in the range-frequency domain. In addition, the channel mismatch in phase and along azimuth baseline position measurement error can also be estimated. Finally, the experimental results of some real squint mode MC-HRWS SAR data are utilised to validate the theoretical investigations and the proposed approach.