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To compensate increasing workload, heart must work harder with structural changes, indicated by increasing size and changing shape, causing cardiac remodeling. However, pathological and unlimited compensated cardiac remodeling will ultimately lead to decompensation and heart failure. In the past decade, numerous studies have explored many signaling pathways involved in cardiac remodeling, but the complete mechanism of cardiac remodeling is still unrecognized, which hinders effective treatment and drug development. As gene transcriptional regulators, transcription factors control multiple cellular activities and play a critical role in cardiac remodeling. This review summarizes the regulation of fetal gene reprogramming, energy metabolism, apoptosis, autophagy in cardiomyocytes and myofibroblast activation of cardiac fibroblasts by transcription factors, with an emphasis on their potential roles in the development and prognosis of cardiac remodeling.

At present, dispersion curves are usually extracted through temporal-spatial analysis methods. To obtain more dispersion information relating to waveguides, the F-K transform is introduced in this paper. Based on Normal Mode theory, the feasibility analysis of the F-K transform employed in dispersion extraction has been provided with deduction and numerical simulation at first. Then, an anechoic tank measurement based on scale model has been carried out so as to demonstrate the research mentioned above, while at the same time the validity of the scale model applied to sound propagation has also been proved by normal mode theory. As for the accuracy and efficiency of measurement, they are further verified by the agreement between the numerical simulation and the analysis results of the measured data.

In the real ocean environment, the compressional and shear wave velocities in an elastic sediment layer vary with depth, leading to the coupling between compressional and shear waves. As the coupling will affect the underwater sound field, in this paper, a typical sound velocity distribution (where the compression wave velocity has an n2 linear distribution and the square of shear wave velocity has a linear distribution) is analyzed. Based on the wave equation in inhomogeneous elastic medium, coupled equations of wavenumber kernels of scalar and vector potential functions are established. Based on the perturbation method, approximate analytical solutions of integration kernels are acquired by successive differentiation. The comparison between theoretical prediction and experimental data, which are from the pressure sensor of ocean-bottom seismometer (OBS) consisting of three orthogonal hydrophones and one hydrophone, located at the bottom of the sea near Qingdao City, shows that the coupling between shear wave and compression wave has little effect on near-field sound propagation, while the prediction of long-range sound propagation needs to consider the influence of eigenvalue change caused by coupling. Theoretic analysis shows that there will be coupling between the two waves only if the gradient, σ, of the square of the shear wave velocity is nonzero. When α, the gradient of the reciprocal of the square of the compression wave velocity, becomes larger, and σ remains unchanged, the simulation results show that the change of the eigenvalue is very small when considering the coupling effect. Thus, transmission loss curves calculated by the coupled and uncoupled algorithm are almost the same. When σ becomes larger while α remains unchanged, the simulation results show that eigenvalues are changed to some extent if considering the coupling effect, and that the difference between transmission loss calculated by the coupled and uncoupled algorithms increases. That means the effect of σ value on coupling is greater than that of α value. In addition, the coupling between the compression wave and shear wave can lead the eigenfunctions and derivative eigenfunctions in the sediment to change. The horizontal displacement and vertical displacement are the Fourier-Bessel integral functions of eigenfunctions and derivative eigenfunctions. So the displacement field of particle in the sediment layer is different in the coupled case from that in the uncoupled cases. By comparing the transmission loss of sound pressure simulated by COMSOL software and that obtained from our proposed method, the correctness of the proposed method is verified. And the calculation time is much shorter than the calculation time by using COMSOL software.

Objective To explore the roles of persistent systemic inflammation in atherosclerosis and the effects of saponins of Panax Notoginseng (PNS) on this process in rabbits. Methods Thirty rabbits were divided randomly and equally into 6 groups, i.e., control, high-fat diet, inflammation, aspirin, PNS and simple-inflammation group. All the animals except that in control group and simple-inflammation group were fed with high-fat diet for 8 weeks. Based on that, rabbits in inflammation, aspirin and PNS groups were treated with zymosan injection (10 mg/kg, i.p.). Normal saline was given to rabbits in control group. Besides zymosan injection, animals in aspirin and PNS group were administrated with aspirin (12 mg/kg, i.g.) and PNS (120 mg/kg, i.g.) respectively. The animals in simple-inflammation group were treated with zymosan injection (10mg/kg, i.p.) and fed with normal diet. The atherosclerosis lesion in aortas was observed by Sudan IV staining. Serum total cholesterol, triglyceride (TG), TNF-α and activity of post-heparin lipoprotein lipase (LPL) were measured at the end of the 4th and 8th week after an overnight fast. Results Compared with high-fat diet group, the area of atherosclerosis lesion, serum TG and TNF-αwere markedly increased in rabbits of inflammation group, and the activity of LPL was decreased remarkably. Serum TNF-α level was negatively correlated with the activity of post-heparin LPL (r = –0.708, P Conclusions Persistent systemic inflammation could accelerate the formation of atherosclerosis lesion in aortas, which partly depend on the decreasing of the activity of post-heparin lipoprotein lipase. PNS could improve the changes caused by inflammation.

Aiming at the passive impulse wideband source range problem in shallow water waveguides, a passive source range method with single hydrophone based on the matched mode processing is presented in this paper, the method is applied to the shallow water waveguide with a bottom of liquid semi-infinite space. Warping transformation is a useful tool to separate the normal modes of the received signals of the impulse source, and the frequency domain signals of each order can be obtained. The seafloor phase shift parameter is an important parameter describing the acoustic parameters of the seafloor, which contains nearly all the information about sea floor, what is more, the seafloor phase shift parameter is also an parameter that can be obtained by some experimental data easily. Each order normal mode can be represented by the expression that contains the phase shift parameter of sea floor. What is more, the influence of sound speed profile of the waveguide on eigenvalue can be approximately eliminated by jointly processing arbitrary two-order normal modes. Sound speed profile has a similar influence on eigenvalue of each order normal mode, therefore, the difference in the eigenvalues between arbitrary two-order normal modes can be approximated represented by the phase shift parameter of the sea-floor, the sea depth and the mean speed in the waveguide. In this way, the phase replica which consists of the eigenvalue difference of each two-order mode can be calculated simply and quickly, and then by constructing cost function and matching normal mode, the underwater impulse source can be located. Compared with the traditional method of processing matched mode and the method of processing matched fields, the method presented in this paper has two advantages: using warping transformation instead of hydrophone arrays to separate the normal modes; the replica can be calculated quickly and easily, depending on a small number of environmental parameters of waveguide. The effectiveness and accuracy of the method are proved by the results of numerical simulation and sea experimental data processing, in which the signals are both received by a single hydrophone. The sea experimental data contain linear frequency modulation impulse source signal and explosion sound source signal, and the mean relative error of range estimation is less than 10%. In the end of this paper, the range estimation error is analyzed, indicating that the error originates mainly from the mode phase parts besides the phase part of Hankel function. Consequently, finding the ways to reduce the range estimation error is an important project in the future.

The phase space reconstruction is an important method of chaotic time series analysis. In this paper, the method is applied to ship radiated noise obtained through both onshore acquisition system and underwater hydrophones. Utilizing the delay coordinate reconstruction method, the two primary parameters, delay time and embedding dimension are determined. By optimizing these two parameters, the reconstructed attractor is gained with prominent structure of nonlinear dynamics. The largest Lyapunov exponent and correlation dimension of the data have also been obtained, both of which exhibit chaotic behavior. Comparing with those of data acquired via hydrophones, it proves that the phase space reconstruction and chaotic time series analysis method is effective to seismic-acoustic signal processing.

This paper focuses on passive polarized wave separation. A new approach is proposed against overlapped Rayleigh and SH waves. The information given by the two three-component sensors is sufficient for the identification of mixing matrix and the estimation of target parameters, such as incident angle, time-delay and the axial ratio of particle motion trajectory. Although the two polarized waves may be coherent, wave separation is realized with the help of intrinsic coherence function based on second order statistics. The feasibility of this algorithm is verified by applying it to emulation continuous Rayleigh and SH waves.

One types of permanent-magnet ac motor drives are available in the drives industry. These are the permanent-magnet synchronous-motor (PMSM) drive with a sinusoidal flux distribution. The application of vector control to the PMSM and complete modeling, simulation, and analysis of the drive system are given. State-space models of the motor and speed controller of the inverter switches and vector controller are included. Performance differences due to the use of pulse width modulation (PWM) and hysteresis current controllers are also examined. Particular attention is paid to the motor torque pulsations and speed response. Some experimental verification of the drive performance is also given.

The model of vehicle routing problem with backhauls is built based on natural description, then an improved immune algorithm for the problem is applied in which a new coding method, the adaptive mechanism of the information entropy of antibody, and evaluate function are introduced. The computational result demonstrates that the high quality solutions to the vehicle routing problem with backhauls can be obtained by using the improved immune algorithm, the new algorithm is also efficient and robust.

The mode coupling and energy transfer are studied by considering the influences of variation in topography on sound energy transmission and structures of interference in a range-dependent waveguide. A larger level-stepped coupled mode model and a three-dimensional coupled mode model for the wedge bottom are obtained such that the mode coupling and energy transfer may be analyzed efficiently and rapidly. According to the coupled mode models, the transfer of energy is expounded for the forward pressure field in the waveguide with varying topography. Meanwhile, the mechanism is explained by the ray-mode theory for variation of energy distribution caused by variation of topography. Numerical simulations show that the coupling between normal modes and the energy transfer may occur remarkably when the imaginary parts of eigenvalues take on a huge modification, and the propagation direction of sound field will be changed to the increasing direction of sea depth due to variation of topography. In the energy transfer and the modification of propagation direction, the energy of sound field tends to remain in the waveguide, rather than to leak to the seafloor. Meanwhile, the energy distribution will be affected by the compression or sparseness so that interference structures such as ellipse, will be produced.