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Additional file 1: Figure S1. A. KEGG analysis performed by pairwise comparison B. Rat model of tendinopathy and tension test machine C. Quantitative analysis of cell viability of TDSCs on GMs and PRP-GMs D. orthostatic and posterior -anterior macroscopic appearance of tendon. Figure S2. A. Differentiation of TDSCs outside the GMs B.Differentiation of TDSCs on the GMs C. PI3K-AKT pathway influenced by PRP-GMs.

In this paper, the compressible immiscible two-phase flow with relaxation is investigated, this model can be regarded as a natural modification of Jin-Xin relaxation scheme proposed and developed by S.Jin and Z.P.Xin([Comm.Pure Appl.Math., 48,1995]) in view of the numerical approximation of conservation laws. Given any entropy solution consists of two different families of shocks interacting at some positive time for the standard two-phase compressible Euler equations, it is proved that such entropy solution is the sharp interface limit for a family global strong solutions of the modified Jin-Xin relaxation scheme for Navier-Stokes/Allen-Cahn system, here the relaxation time is selected as the thickness of the interface, weighted estimation and improved antiderivative method are used in the proof. Moreover, the simulation results are given by this modified Jin-Xin relaxation scheme method. Both numerical and theoretical results show that, the interacting shock waves can pass through the interface without any effect., 25 pages, 9 figures

The datalink of an unmanned aerial vehicle (UAV) is vulnerable to external electromagnetic interference (EMI). The characteristic parameters of the EMI signal can be definitively detected by a developed monitoring platform mounted on the UAV, but it is impossible to determine the lost-link thresholds of the datalink in any state by experiment because the state of the datalink varies dynamically with the flight distance and the UAV's attitudes. In this case, whether a certain state of the UAV's datalink will be interrupted or not by the EMI cannot be evaluated. In this article, a method of EMI prediction for the UAV's dynamic datalink based on the Gaussian process regression (GPR) is proposed, two indicators, including the interfering frequency and the operation signal power of the datalink, are taken as the training inputs, and the lost-link thresholds of the datalink obtained by the EMI injection test are taken as the training targets. The results show that this method can effectively fit the training samples and determine a 95% confidence interval of the predictive outputs, which has a low predictive error, less than 2.2 dB. Compared with the methods of the layer recurrent neural network and support vector machine, the GPR method has higher predictive accuracy and a stronger generalization ability. Therefore, the detected EMI characteristic parameters can be used as new input samples to predict the lost-link thresholds in any condition. On this basis, the EMI margin can be calculated to evaluate the degree of the anti-EMI redundancy of the UAV's datalink, which can be used for the active adaptation of the UAV's datalink to EMI in the future.

Unmanned aerial vehicle (UAV) is likely to be interfered by high-power microwave (HPM) pulse, especially its datalink. To investigate the effects of HPM pulse on the datalink of a UAV in a dynamic flight scenario, a tracking interference model for an HPM source toward a UAV is proposed, as well a dynamic flight model is also built to determine the HPM reception of the UAV's datalink. In order to predict the possible effects of HPM on the datalink, the tests on a certain type of UAV's datalink are carried out in the presence of HPM with its carrier frequency in L -, S - and C -band, respectively. The results show that the electromagnetic interference (EMI) can easily enter the receiver via front-door when the carrier frequency of the HPM falls into the operating frequency band of the datalink, which will lead to a permanent physical damage. However, when the carrier frequency deviates from the operating frequency band of the datalink, the EMI couples into the incomplete shielded power line via back-door and generates a high-voltage signal at the power port, resulting in a transient lost-link effect or even a functional failure of the datalink due to its abnormal electric power supply. Finally, some suggestions are put forward to improve the UAV's adaptability in the HPM environment.

Additional file 1: Table S1. Characters of prepared micropatterns. The data are calculated from 3 independent micropatterns. Table S2. Diameters and spreading areas of micropatterned and non-patterned MG63 cells. The data are calculated from five cells for each type micropatterns.

The three-dimensional (3D) full compressible magnetohydrodynamic system is studied in a general bounded domain with slip boundary condition for the velocity filed, adiabatic condition for the temperature and perfect conduction for the magnetic field. For the regular initial data with small energy but possibly large oscillations, the global existence of classical and weak solution as well as the exponential decay rate to the initial-boundary-value problem of this system is obtained. In particular, the density and temperature of such a classical solution are both allowed to vanish initially. Moreover, it is also shown that for the classical solutions, the oscillation of the density will grow unboundedly with an exponential rate when the initial vacuum appears (even at a point). Some new observations and useful estimates are developed to overcome the difficulties caused by the slip boundary conditions., Comment: 58 pages. arXiv admin note: text overlap with arXiv:2102.07341, arXiv:2207.00441; text overlap with arXiv:1107.4655, arXiv:2102.06348 by other authors

The operation signal of an unmanned aerial vehicle's (UAV's) datalink will change with the flight radius and attitude, which leads to a dynamic variation of the electromagnetic susceptibility (EMS) of the datalink against the external electromagnetic interference. In order to predict the electromagnetic compatibility (EMC) for the dynamic datalink of a UAV, the operation signal of the UAV's datalink and the received interference by the UAV need to be quantified and the EMS is also necessary to be tested. In this paper, a new model of the UAV's datalink in different flight states is presented. The relationship among the airborne operation signal, the interference and the flight parameters is presented and compared in three typical flight states, i.e., the fixed angle state, dive state, and hover state. To increase the repeatability and accuracy of the test and avoid risks in a flight test, a novel EMS test method using a static test instead of a dynamic flight test is proposed. On the basis of the operation state and its corresponding EMS threshold, the EMC prediction is performed to determine the moment when the datalink will be interrupted. The new method can be used to improve the security of UAV in the severe electromagnetic environment.

We deal with the barotropic compressible magnetohydrodynamic equations in three-dimensional (3D) bounded domain with slip boundary condition and vacuum. By a series of a priori estimates, especially the boundary estimates, we prove the global well-posedness of classical solution and the exponential decay rate to the initial-boundary-value problem of this system for the regular initial data with small energy but possibly large oscillations. The initial density of such a classical solution is allowed to contain vacuum states. Moreover, it is also shown that the oscillation of the density will grow unboundedly with an exponential rate when the initial state contains vacuum., 42 pages. arXiv admin note: text overlap with arXiv:2102.06348. substantial text overlap with arXiv:2102.07938; substantial text overlap with arXiv:2102.06348 by other authors

In this paper we study the initial-boundary-value problem for the barotropic compressible magnetohydrodynamic system with slip boundary conditions in three-dimensional exterior domain. We establish the global existence and uniqueness of classical solutions to the exterior domain problem with the regular initial data that are of small energy but possibly large oscillations with constant state as far field which could be either vacuum or nonvacuum. In particular, the initial density of such a classical solution is allowed to have large oscillations contain vacuum states. Moreover, the large-time behavior of the solution is also shown., Comment: 37 pages. arXiv admin note: substantial text overlap with arXiv:2102.07341; text overlap with arXiv:2102.06348, arXiv:2104.10606 by other authors

We consider the initial-boundary-value problem of the isentropic compressible Navier-Stokes-Poisson equations subject to large and non-flat doping profile in 3D bounded domain with slip boundary condition and vacuum. The global well-posedness of classical solution is established with small initial energy but possibly large oscillations and vacuum. The steady state (except velocity) and the doping profile are allowed to be of large variation., Comment: 31 pages. Revised the proof of Lemma 3.7 and corrected some typos. arXiv admin note: substantial text overlap with arXiv:2102.07341; text overlap with arXiv:2102.06348

In this paper, we study the barotropic compressible magnetohydrodynamic equations with the shear viscosity being a positive constant and the bulk one being proportional to a power of the density in a general two-dimensional bounded simply connected domain. For initial density allowed to vanish, we prove that the initial-boundary-value problem of 2D compressible MHD system admits the global strong and weak solutions without any restrictions on the size of initial data provided the shear viscosity is a positive constant and bulk one is $\lambda=\rho^\beta$ with $\beta>4/3$. As we known, this is the first result concerning the global existence of strong solutions to the compressible MHD system in general two-dimensional bounded domains with large initial data and vacuum., Comment: 33 pages. arXiv admin note: substantial text overlap with arXiv:2102.09229 by other authors

The data link, which is the most important part of unmanned aerial vehicle (UAV), is easily affected by external electromagnetic interference (EMI) in identical and adjacent frequency. To deal with the problem of EMI in frequency band, a method that is early warning and then adopts frequency hopping or other measures is proposed, according to operating frequency band of the data link, the radiation effect experiments on a certain type of UAV’s data link under different flight distance are carried out. The experimental results reveal the dynamic range of lost-link thresholds of the data link, on the basis, the suitable EMI monitoring device installed UAV is designed. Several state parameters of the data link such as error rate, receiving auto gain control (AGC) and signal to noise ratio (SNR) are described, and characteristic of the lost-link threshold and the above three parameters in early warning state and lostlink state respectively is compared and analyzed in terms of variety range, 6dB early warning or not, stability of value and correlation with interfering frequency and operating signal power. Finally, a parameter with the lowest uncertainty is determined as the prediction criterion of the data link suffered by EMI, and when external interfering signal power reaches between the early warning value and lost link threshold, the corresponding measures will be activated to protect UAV’s data link from interruption.

The Cauchy problem for non-isentropic compressible Navier-Stokes/Allen-Cahn system with degenerate heat-conductivity $\kappa(\theta)=\tilde{\kappa}\theta^\beta$ in 1-d is discussed in this paper. This system is widely used to describe the motion of immiscible two-phase flow in numerical simulation. The wellposedness for strong solution of this problem is established with the $H^1$ initial data for density, temperature, velocity, and the $H^2$ initial data for phase field. The result shows that no discontinuity of the phase field, vacuum, shock wave, mass or heat concentration will be developed at any finite time in the whole space. From the hydrodynamic point of view, this means that no matter how complex the interaction between the hydrodynamic and phase-field effects, phase separation will not occur, but the phase transition is possible., Comment: 18 pages

We have described the synthesis of the two complex units (2 R ,3 R ,4 S )-dolaproine (Dap) and (3 R ,4 S ,5 S )-dolaisoleuine (Dil) of dolastatin 10 from natural amino acids. The stereoselective syntheses of N- Boc-Dap ( 4a ) and N -Boc-(2 S )- iso -Dap ( 4b ) were performed by employing crotylation of N -Boc- l -prolinal as a key step. Barbier-type allylation of N -Boc- l -isoleucinal provided a mild and convenient approach for the synthesis of N -Boc-Dil ( 5a ) and N -Boc-(3 S )- iso -Dil ( 5b ). Ten dolastatin 10 analogues have been designed and synthesized with N-terminal modifications based on the known compound monomethylauristatin F (MMAF, 3 ). In comparison with MMAF ( 3 ), four of the compounds showed enhanced potency against HCT 116 human colon cancer cells in vitro .

With the gradual improvement of the Beidou system, the Beidou navigation receiver begins to be widely used, but due to the low power of navigation signal, the navigation receiver is easily disturbed and cannot work normally. This paper take Beidou navigation receiver as experiment object, and study the sensitive voltage and effect under the condition of ESD, The experiment shows that the positioning function of the receiver is not affected by ESD, but the data output serial port is susceptible to interference, so that the upper computer cannot obtain the effective information of navigation and positioning in time. The conclusion provides a basis for the electromagnetic protection of the navigation receiver.

2019, この博士論文は、全文公表に適さないやむを得ない事由があり要約のみを公表していましたが、解消したため、令和4(2022)年7月14日に全文を公表しました。

This paper is concerned with the evolution of the periodic boundary value problem and the mixed boundary value problem for a compressible mixture of binary fluids modeled by the Navier-Stokes-Cahn-Hilliard system in one dimensional space. The global existence and the large time behavior of the strong solutions for these two systems are studied. The solutions are proved to be asymptotically stable even for the large initial disturbance of the density and the large velocity data. We show that the average concentration difference for the two components of the initial state determines the long time behavior of the diffusive interface for the two-phase flow., 25 pages

This paper is concerned with the large-time behavior of solutions to the outflow problem of full compressible Navier-Stokes equations in the half line. This is one of the series of papers by the authors on the stability of nonlinear waves to the outflow problem. We show the time asymptotic stability of degenerate (transonic) stationary solution for the general gas including ideal polytropic gas. The key point of the proof is based the new property of the degenerate stationary solution and the delicate energy estimates., Comment: 19 pages

A kind of low-cost electric and magnetic field simulators, which are used to produce simulative lightning electromagnetic pulse (LEMP) with adjustable waveforms and intensity output, are presented. The lightning electric field can be produced within the GTEM cell by feed-in of impulse voltage output by a Marx generator. The lightning magnetic field can be produced within the coil by feed-in of surge current from the lightning surge generator. The simulated magnetic field is measured by a “B-dot” coil. The measured results show that the lightning electric field simulator and magnetic field simulator could provide relatively homogeneous LEMP environment within certain area in the GTEM cell and the coil within 3 dB deviation. The effects of the simulated lightning electric fields on some electronic devices and the influence of the turns and size of the coil on the homogeneity of the simulated magnetic fields are also investigated.

Bt toxins bind to receptors in the brush border membrane of the insect gut and create pores, leading to insect death. Bt-resistant insects demonstrate reduced binding of the Bt toxins to gut membranes. However, our understanding of the gut receptors involved in Bt toxin binding, and which receptors confer resistance to these toxins is incomplete, especially in diamondback moth (Plutella xylostella), a major agricultural pest. Identifying receptors has remained challenging because we lack sufficiently sensitive methods to detect Bt receptor interactions. Here, we report a modified far-immunoblotting technique, which revealed a broad spectrum of binding targets for the Bt toxins Cry1Ac, Cry1Ab, and Cry1Bd in diamondback moth. We confirm the role of the glucosinolate sulfatases GSS1 and GSS2 in Cry1Bd toxicity. GSS1 and GSS2 bind directly to Cry1Bd, and their expression is crucial for Cry1Bd toxicity. These results improve our understanding of the molecular mechanisms of Bt toxicity.AUTHOR SUMMARYThe Bt toxins, from the soil bacteriumBacillus thuringiensis, have wide applications in agriculture as insecticides applied to plants or expressed in genetically modified crops. Bt toxins bind to receptors in the brush border membrane of the insect gut and create pores leading to insect death. The success of the Bt toxins in controlling insect pests has been hindered by the emergence of resistant insects, which show reduced binding of Bt to their gut membranes. Although ongoing research has identified a few receptors, many remain unknown and the mechanisms by which these receptors cause resistance remain unclear. Here, we used a modified far-immunoblotting technique to identify proteins that bind to the toxins Cry1Ac, Cry1Ab, and Cry1Bd in the diamondback moth. This identified two glucosinolate sulfatases that bind directly to Cry1Bd; also, the toxicity of Cry1Bd requires expression of these glucosinolate sulfatases. Therefore, identification of these candidate receptors improves our understanding of Bt function and resistance.

The data link is an important guarantee for the Unmanned Aerial Vehicle (UAV) equipment to complete its battlefield functions. Its anti-electromagnetic pulse interference capability directly affects the airborne communication security. Ultra-wideband (UWB) electromagnetic pulse has become an important source of electromagnetic interference due to its high power, wide frequency band and wide interference target. In order to verify the reliability of UAV data link communication under UWB electromagnetic pulse irradiation conditions, the UWB electromagnetic pulse irradiation effect experiment of UAV was carried out, and the mechanism of “lost lock” effect of UAV data link was analyzed. The experimental results show that when the UWB electromagnetic pulse irradiation intensity reaches 140 kV / m, it will cause hardware damage to the UAV, and found that its internal sensitive device low noise amplifier is damaged. In response to this, the comprehensive design of the electromagnetic protection measures for the UAV was carried out, laying the foundation for the next step to strengthen the electromagnetic protection of the UAV.

On basis of experimental study and consideration about the two ways of charge dissipation — corona discharge and electrostatic conduction, a test method of frictional voltage decaying which can evaluate the electrostatic properties of fabrics is presented, and the frictional voltage decaying test device for fabrics is developed. Experimental data show that this method and device can evaluate the electrostatic properties of fabrics overall.

In order to study the safety and reliability of Unmanned Aerial Vehicle in the battlefield electromagnetic environment, a continuous-wave electromagnetic radiating system is built in the laboratory. Using this system, experiments on irradiation effect for U AV data link system are implemented. Experimental results show that: the UAV data link system is susceptible to electromagnetic interference and can't work well in some frequencies. The UAV data link system would fall in state of losing lock, which means the data transmission between UAV and the ground control equipment would not be carried on effectively. What is more, different polarization direction of radiated electromagnetic field leads to different values of the electric field threshold for the communication link system losing lock. Analysis on results shows that the energy coupling channel between UAV data link systems and continuous-wave electromagnetic radiating system is the way of “back door” coupling.

In order to protect sensitive electronic components and electrical equipment against the influence of lightning electromagnetic pulse (LEMP) field in near area, it is necessary to determine the waveform of the lightning electromagnetic field. By using the dipole method to solve Maxwell’s equations, the analytical expressions of lightning electromagnetic fields which is generated by oblique discharge channel are presented. According to the TL model, the general approximate derivative expressions of lightning electromagnetic field are derived and the waveforms of the exact expressions as well as approximate expressions are compared in near area. The results showed that the electromagnetic field derivative waveforms of the approximate results are essentially coincident with that of the accurate results within 100 m and the deviation between the accurate result, and the approximate result increased with the increasing of the horizontal distance; the deviation between the approximate result and the exact result of magnetic field is larger than that of electric field within the same distance. From above analyses it can be concluded that there is an approximation between the lightning electromagnetic field and channel base current and from then on we can get lightning electromagnetic field more effectively.

Choice of the return-stroke parameters has a great influence on the calculation results of lightning electromagnetic pulse(LEMP) fields. In this paper, LEMP fields under different return-stroke parameters are calculated based on the MTLL model in which the channel-base current is described by a pulse function. And effect of different return-stroke speeds and channel heights on LEMP fields of different field regions are also discussed. The results show that the lightning channel height between 1 kilometre and a few tens of kilometres has a little influence on the LEMP fields, but the return-stroke speed has a distinct influence on the LEMP fields.

Vehicle engineering major includes mechanical engineering, structural engineering, transportation engineering, etc. This paper introduces problems of traditional vehicle engineering teaching. We should strengthen the base of discipline construction to increase students’ learning interest. At last, a method of training vehicle engineering innovative application talents is introduced.

In allusion to the disadvantages of double exponential function and Heidler function which are widely used to describe lightning channel-base current, a new kind of lightning channel-base current model is presented. The comparison among the three kinds of function shows that the new function is predominant over the other two. It is highly efficient in calculating lightning electromagnetic pulse fields (LEMP).

The lightning magnetic field is simulated when a pulse current is injected into the loop from the lightning surge generator. Different waveforms of lightning magnetic field can be simulated by regulating the parameters of the loop according to the relation between the parameters of the loop and the simulated wave. The dot loop is made to measure the magnetic field in the big loop and the results show that the M-field is relative even among a curtain area of the big loop, which is appropriate to test the lightning M-field effect on electromagnetic sensitive devices.

The electromagnetic field is calculated by the dipole technique. The waveforms of EM field in remote area and the channel-base current are compared. Also the derivative of EM field in remote area and that of the channel-base current are compared. According to the comparison, it shows that the qualification of approximation between the EM field and channel-base current is more strict than that between the derivative of the EM field and channel-base current.

The analytic expressions of the spatial lightning electromagnetic field are obtained by solving Maxwell's Equations based on the dipole method. On this basis, the waveforms of the electric and magnetic fields at different heights and distances in the near-zone are presented using the transmission line (TL) model and the channel-base current was described by the impulse function. The result shows that at a same height to the ground, the rising edges of the electromagnetic field waveforms become subdued and the peak values decrease with the increase of the horizontal distance. For the electromagnetic field at the same distance, the rising edge of the waveform becomes steep gradually with the increasing height of the observation point. The peak value of the horizontal electric field increases with increasing height of the observation point and the peak value of the magnetic field basically remains unchanged. The study can provide useful information for protecting the electronic equipment from the destruction of LEMP.