Dynamic symmetry breaking and structure-preserving analysis on thelongitudinal wave in an elastic rod with a variable cross-section

The longitudinal wave propagating in an elastic rod with a variable cross-section owns wide engineering background,in which the longitudinal wave dissipation determines some important performances of the slender structure.To reproduce the longitudinal wave dissipation effects on an elastic rod with a variable cross-section,a structure-preserving approach is developed based on the dynamic symmetry breaking theory.For the dynamic model controlling the longitudinal wave propagating in the elastic rod with the variable cross-section,the approximate multi-symplectic form is deduced based on the multi-symplectic method,and the expression of the local energy dissipation for the longitudinal wave propagating in the rod is presented,referring to the dynamic symmetry breaking theory.A structure-preserving method focusing on the residual of the multi-symplectic structure and the local energy dissipation of the dynamic model is constructed by using the midpoint difference discrete method.The longitudinal wave propagating in an elastic rod fixed at one end is simulated,and the local/total energy dissipations of the longitudinal wave are investigated by the constructed structure-preserving scheme in two typical cases in detail.

Coupling dynamic characteristics of simplified model for tethered satellite system

connecting wires are the main manifestations of the coupling dynamic effects on the orbit evolution,the attitude adjusting and the flexible vibration of the tethered satellite system.To investigate attitude evolution of the tethered system and the mechanical energy transfer/loss characteristics between the bus system and the solar sail via the connecting wires,a structure-preserving method is developed in this paper.Simplifying the tethered satellite system as a composite structure consisting of a particle and a flexible thin panel connected by four special springs,the dynamic model is deduced via the Hamiltonian variational principle firstly.Then,a structure-preserving approach that connects the symplectic Runge-Kutta method and the multi-symplectic method is developed.The excellent structure-preserving property of the numerical scheme constructed is presented to illustrate the credibility of the numerical results obtained by the constructed structure-preserving approach.From the numerical results on the mechanical energy transfer/loss in the composite structure,it can be found that the mechanical energy transfer tendency in the tethered system is dependent of the initial attitude angle of the system while the total mechanical energy loss of the system is almost independent of the initial attitude angle.In addition,the special stiffness range of the spring is found in the attitude angle evolution of the system,which provides a structural parameter design window for the connecting wires,that is,the duration needed to arrive the stable attitude is short when the stiffness of the wire is designed in this special range.

One Novel Long Noncoding RNA lnc10 in Drosophila

With the development of computational methods and RNA sequencing technology for assembling the transcriptome, it is becoming clear that the mammal genome is pervasively tran- scribed, and large numbers of long noncoding RNAs （lncRNAs） composing the major part of the transcriptome have been identified （Ravasi et al., 2006; Birney et al., 2007;

Clinical efficacy observation of comprehensive ying needling therapy for mumps

Objective： To compare the clinical efficacy difference between comprehensive ying needling therapy and intramuscular injection with ribavirin for mumps.Methods： One hundred patients with mumps were randomly divided into comprehensive ying needling therapy group（group A, 52 cases） and western medicine group（group B, 48 cases）, then 8 cases were eliminated and drop out from group A and 4 cases were eliminated and drop out from group B respectively. actual inclusion 44 cases in group A 44 cases in group B. Point bloodletting was performed at parotid gland（腮腺Sāixiàn） and Threeshang acupoints of the patients in group A for once every other day, treatment for 7 days was considered as 1 course of treatment, and 2 courses were needed. Intramuscular injection with ribavirin was given to the patients in group B for twice a day, treatment for 7 days was considered as 1 course, and 2 courses were needed. The parotid gland swelling score, fever score, orifice parotid duct swelling score, score of difficulty in opening mouth and the clinical efficacy of the patients in the two groups were compared before and after treatment.Results： The cured and markedly effective rate in group A was 90.9%（40/44）, which was superior to 68.2%in group B（30/44）（P〈0.05）. The symptom scores were all improved significantly in the two groups after treatment（all P〈0.05）, and the improvement in group A was superior to that in group B（all P〈0.05）.Conclusion： The curative effect of comprehensive ying needling therapy for treatment of mumps was superior to that of conventional western medicine therapy.