The species in ecosystems are mutually interacting and self sustainable stable for a certain period. Stability and dynamics are crucial for understanding the structure and the function of ecosystems. We developed a potential and flux landscape theory of ecosystems to address these issues. We show that the driving force of the ecological dynamics can be decomposed to the gradient of the potentia...

Metal ions play crucial roles in thermal stability and folding kinetics of nucleic acids. For ions (especially multivalent ions) in the close vicinity of nucleic acid surface, interion correlations and ion-binding mode fluctuations may be important. Poisson-Boltzmann theory ignores these effects whereas the recently developed tightly bound ion (TBI) theory explicitly accounts for these effects....

We consider an emulsion whose droplets contain a trapped species (insoluble in the continuous phase), and study the emulsion’s stability against coarsening via Lifshitz–Slyozov dynamics (Ostwald Ripening). Extending an earlier treatment by Kabalnov et al(Colloids and Surfaces, 24 (1987), 19-32), we derive a general condition on the mean initial droplet volume which ensures stability, even when ...

We perform a comprehensive study of stability of a pumped atom laser in the presence of pumping, damping, and outcoupling. We also introduce a realistic feedback scheme to improve stability by extracting energy from the condensate and determine its effectiveness. We find that while the feedback scheme is highly efficient in reducing condensate fluctuations, it usually does not alter the stabili...

We discuss the stability of semiclassical gravity solutions with respect to small quantum corrections by considering the quantum fluctuations of the metric perturbations around the semiclassical solution. We call the attention to the role played by the symmetrized two-point quantum correlation function for the metric perturbations, which can be naturally decomposed into two separate contributio...

Introduction: Some plants show antimicrobial activity against wide range of microorganism. The aim of this study was to investigate the antimicrobial activity and stability of Zataria multiflora Boiss and Satureja khuzestanica essential oil (EO). Materials and methods: First, these plants (Zataria multiflora Boiss and Satureja khuzestanica) were collected, verified by a botanist, dried, and gr...

Nonlinear simulation with a simple resistive magnetohydrodynamics model is used to investigate the stabilization of magnetic fluctuations in reversed-field pinch plasmas subject to pulsed-parallel current drive. Numerical results are diagnosed with computations of nonlinear power transfer and by evaluating sequences of profiles for linear stability. Results show that poloidal electric field pul...

We study by mean-field analysis and stochastic simulations chemical models for genetic toggle switches formed from pairs of genes that mutually repress each other. To determine the stability of the genetic switches, we make a connection with reactive flux theory and transition state theory. The switch stability is characterized by a well-defined lifetime tau. We find that tau grows exponentiall...

A multidisciplinary approach based on molecular dynamics (MD) simulations using homology models, NMR spectroscopy, and a variety of biophysical techniques was used to efficiently improve the thermodynamic stability of armadillo repeat proteins (ArmRPs). ArmRPs can form the basis of modular peptide recognition and the ArmRP version on which synthetic libraries are based must be as stable as poss...

Rangeland ploughing and cultivation using dry land farming crops may be amajor reason for the destruction of natural resources in the semiarid and sub-humid regionswhich may significantly change the composition and reduce the stability of the affectedcommunities. In present research, an abandoned ploughed site was compared with a nearbyreference site in the semiarid rangelands of Baharkish, Quc...