Early and late stage profiles for a new chemotaxis model with density-dependent jump probability and quorum-sensing mechanisms

In this paper, we derive a new chemotaxis model with degenerate diffusion and density-dependent chemotactic sensitivity, and we provide a more realistic description of cell migration process for its early and late stages. Different from the existing studies focusing on the case of non-degenerate diffusion, the new model with degenerate diffusion causes us some essential difficulty on the boundedness estimates and the propagation behavior of its compact support. In the presence of logistic damping, for the early stage before tumour cells spread to the whole body, we first estimate the expanding speed of tumour region as $O(t^{\beta})$ for $0<\beta<\frac{1}{2}$. Then, for the late stage of cell migration, we further prove that the asymptotic profile of the original system is just its corresponding steady state. The global convergence of the original weak solution to the steady state with exponential rate $O(e^{-ct})$ for some $c>0$ is also obtained

Experimental research and numerical analysis on vibroacoustic characteristics of the laminated composite plate and its application in high-speed trains

This paper firstly used the finite element method to study the impact of air coupling on the structural radiation noise of thin plates and conducted a comparative analysis on the vibration noise of thin plates in the water and air. Results showed that coupling effect and medium property had an obvious influence on the radiation noise of thin plates, and these factors must be considered. Secondly, this paper proposed laminated plates based on the single-layered thin plate. The related experiment of laminated plates was conducted and compared with the computational result to verify its reliability. As an important parameter of laminated plates, laying angle can change the structural stiffness of laminated plates and mechanical properties. Therefore, based on the verified computation model, this paper studied the radiation noise of laminated plates through changing the laying angle of laminated plates, improved the vibration noise of laminated plates through applying control forces. As a result, a laminated plate with the optimal performance can be obtained. Finally, laminated composite plates were applied to the inner surface of panels which had made greater acoustic contributions to high-speed trains and controlled the vibration noise of high-speed trains through applying control forces. Results showed that the peak noise of high-speed trains was obviously improved at multiple frequencies and total sound power levels reduced by 23.1 dB

Periodicities in the occurrence of aurora as indicators of solar variability

A compilation of records of the aurora observed in China from the Time of the Legends (2000 - 3000 B.C.) to the mid-18th century has been used to infer the frequencies and strengths of solar activity prior to modern times. A merging of this analysis with auroral and solar activity patterns during the last 200 years provides basically continuous information about solar activity during the last 2000 years. The results show periodicities in solar activity that contain average components with a long period (approx. 412 years), three middle periods (approx. 38 years, approx. 77 years, and approx. 130 years), and the well known short period (approx. 11 years)

CRL Ubiquitin Ligases and DNA Damage Response

Cullin/RING ubiquitin ligases (CRL) comprise the largest subfamily of ubiquitin ligases. CRLs are involved in cell cycle regulation, DNA replication, DNA damage response (DDR), development, immune response, transcriptional regulation, circadian rhythm, viral infection, and protein quality control. One of the main functions of CRLs is to regulate the DDR, a fundamental signaling cascade that maintains genome integrity. In this review, we will discuss the regulation of CRL ubiquitin ligases and their roles in control of the DDR

5-(4-Nitro­benz­yl)-1H-1,2,3,4-tetra­zole

In the title compound, C8H7N5O2, the dihedral angle between the benzene and tetra­zole rings is 63.13 (8)°. The crystal structure exhibits inter­molecular N—H⋯N hydrogen bonds which lead to the formation of one-dimensional chains along the [010] direction