Rare horizontal transmission does not hide long-term inheritance of SINE highly conserved domains in the metazoan evolution

Transposable elements （TEs） are self-replicating, mobile DNA sequences which constitute a significant fraction of eukaryotic genomes. They are generally considered selfish DNA, as their replication and random insertion may have deleterious effects on genome functionalities, although some beneficial effects and evolutionary potential have been recognized. Short interspersed elements （SINEs） are non-autonomous TEs with a modular structure： a small RNA-related head, a body, and a long interspersed element-related tail. Despite their high turnover rate and de novo emergence, the body may retain highly conserved domains （HCDs） shared among divergent SINE families： in metazoans, at least nine HCD-SINEs have been recognized. Data mining on public molecular databases allowed the retrieval of 16 new HCD-SINE families from cnidarian, molluscs, arthropods, and vertebrates. Tracking the ancestry of HCDs on the metazoan phylogeny revealed that some of them date back to the Radiata-Bilateria split. Moreover, phylogenetic and age versus divergence analyses of the most ancient HCDs suggested that long-term vertical inheritance is the rule, with few horizontal transfer events. We suggest that the evolutionary conservation of HCDs may be linked to their potential to serve as recombination hotspots. This indirectly affects host genomes by maintaining active and diverse SINE lineages, whose insertions may impact （either positively or negatively） on the evolution of the genome.

Main Principles and Methods of Identification of High Conservation Value Forests in the Conditions of Mountainous Relief： Case of Armenia

Armenia is a small mountainous country with remarkable biodiversity. The forest cover of Armenia makes up 11.17% of the total territory of Armenia. The forests of Armenia make important habitat for numerous biological objects. They also provide important ecosystem services, including key services to forest adjacent population. Deforestation and forest degradation are serious threats in Armenia. In the result of special studies the principles and criteria for identification of HCVFs （high conservation value forests） in the conditions of Armenia were developed. They are based on the guidelines for identification and management of HCVFs, but adapted to the conditions of mountainous forests of Armenia as a small country. Out of six generic types of HCVFs, it is suggested to define five types of HCVFs with respective sub-types. Proper protection of such forests shall ensure conservation of biological diversity and maintenance of ecosystem services provided by forests.

High order symplectic conservative perturbation method for time-varying Hamiltonian system

This paper presents a high order symplectic con- servative perturbation method for linear time-varying Hamil- tonian system. Firstly, the dynamic equation of Hamilto- nian system is gradually changed into a high order pertur- bation equation, which is solved approximately by resolv- ing the Hamiltonian coefficient matrix into a ＂major compo- nent＂ and a ＂high order small quantity＂ and using perturba- tion transformation technique, then the solution to the orig- inal equation of Hamiltonian system is determined through a series of inverse transform. Because the transfer matrix determined by the method in this paper is the product of a series of exponential matrixes, the transfer matrix is a sym- plectic matrix; furthermore, the exponential matrices can be calculated accurately by the precise time integration method, so the method presented in this paper has fine accuracy, ef- ficiency and stability. The examples show that the proposed method can also give good results even though a large time step is selected, and with the increase of the perturbation or- der, the perturbation solutions tend to exact solutions rapidly.

Comparative Research on Zoning of High Conservation Value Forest and Ecological Forest

High conservation value forest(HCVF) theory has aroused wide concerns among related forestry sectors in China,but the zoning and identification of HCVF only have been implemented in a few forest management units(FMUs). As there is no quantitative indicator for identifying and zoning HCVF in China,most FMUs are unable to have an exact zoning result. This paper introduced the concepts of HCVF and ecological forest,and compared their similarities and differences in terms of identification criteria,zoning methods and application scope. With four Chinese FMUs as case studies,some suggestions were proposed for establishing a zoning scheme of HCVF so as to promote the development of HCVF in China.

Long Time Energy and Kinetic Energy Conservations of Exponential Integrators for Highly Oscillatory Conservative Systems

In this paper,we investigate the long-time near-conservations of energy and kinetic energy by the widely used exponential integrators to highly oscillatory conservative systems.The modulated Fourier expansions of two kinds of exponential integrators have been constructed and the long-time numerical conservations of energy and kinetic energy are obtained by deriving two almost-invariants of the expansions.Practical examples of the methods are given and the theoretical results are confirmed and demonstrated by a numerical experiment.

Improving energetics in an ideal baroclinic instability case with a Physical Conserving Fidelity model

To improve the energetics in the life cycle of an ideal baroclinic instability case, we develop a Physical Conserving Fidelity model （F-model）, and we compare the simulations from the F-model to those of the traditional global spectral semi-implicit model （control model）. The results for spectral kinetic energy and its budget indicate different performances at smaller scales in the two models. A two-way energy flow emerges in the generation and rapid growth stage of the baroclinic disturbance in the F-model. However, only a downscale mechanism dominates in the control model. In the F-model, the meso- and smaller scales are energized initially, and then an active upscale nonlinear cascade occurs. Thus, disturbances at prior scales are forced by both downscale and upscale energy cascades and by conversion from potential energy. An analysis of the eddy kinetic energy budget also shows remarkable enhancement of the energy conversion rate in the F-model. As a result, characteristics of the ideal baroclinic wave are greatly improved in the F-model, in terms of both intensity and time of formation.