A new species of the genus Phanerotoma Wesmael (Braconidae: Cheloninae) with a key to Indian species

A new species of Phanerotoma viz., P. malabarica Sheeba & Narendran sp. nov. from India is described and compared with its closest relative. A key to Indian species of Phanerotoma is also provided

Event--related desynchronization in diffusively coupled oscillator models

We seek explanation for the neurophysiological phenomenon of event related desynchronization (ERD) by using models of diffusively coupled nonlinear oscillators. We demonstrate that when the strength of the event is sufficient, ERD is found to emerge and the accomplishment of a behavioral/functional task is determined by the nature of the desynchronized state. We illustrate the phenomenon for the case of limit cycle and chaotic systems. We numerically demonstrate the occurrence of ERD and provide analytical explanation. We also discuss possible applications of the observed phenomenon in real physical systems other than the brain.Comment: Accepted in Physical Review Letter

Chimera and globally clustered chimera: Impact of time delay

Following a short report of our preliminary results [Phys. Rev. E 79, 055203(R) (2009)], we present a more detailed study of the effects of coupling delay in diffusively coupled phase oscillator populations. We find that coupling delay induces chimera and globally clustered chimera (GCC) states in delay coupled populations. We show the existence of multi-clustered states that act as link between the chimera and the GCC states. A stable GCC state goes through a variety of GCC states, namely periodic, aperiodic, long-- and short--period breathers and becomes unstable GCC leading to global synchronization in the system, on increasing time delay. We provide numerical evidence and theoretical explanations for the above results and discuss possible applications of the observed phenomena.Comment: 10 pages, 10 figures, Accepted in Phys. Rev.

A general coupled-nonlinear-oscillator model for event-related (de)synchronization

Changes in the level of synchronization and desynchronization in coupled oscillator systems due to an external stimulus are called event-related synchronization or desynchronization (ERS or ERD). Such changes occur in real-life systems where the collective activity of the entities of a coupled system is affected by some external influence. In order to understand the role played by the external influence in the occurrence of ERD and ERS, we study a system of coupled nonlinear oscillators in the presence of an external stimulus signal. We find that the phenomena of ERS and ERD are generic and occur in all types of coupled oscillator systems. We also find that the same external stimulus signal can cause ERS and ERD depending upon the strength of the signal. We identify the stability of the ERS and ERD states and also find analytical and numerical boundaries between the different synchronization regimes involved in the occurrence of ERD and ERS

Design of Filter Using MOS Current Mode Logic

MCML (MOS Current Mode Logic) is a method used for the purpose of reducing the delay and power of the circuit. In high speed application this method is used to reduce the power. In this method the sleep transistor is inserted in series with the supply voltage (or) current source to reduce the power. Different power gating techniques are been used to reduce the static power and to improve the speed and efficiency of the circuit. In this paper, the filter can be designed by using MCML logic. The fourth order band pass filter by using MCML logic is introduced. In order to reduce the power and delay this method is proposed

Globally clustered chimera states in delay--coupled populations

We have identified the existence of globally clustered chimera states in delay coupled oscillator populations and find that these states can breathe periodically, aperiodically and become unstable depending upon the value of coupling delay. We also find that the coupling delay induces frequency suppression in the desynchronized group. We provide numerical evidence and theoretical explanations for the above results and discuss possible applications of the observed phenomena.Comment: Accepted in Phys. Rev. E as a Rapid Communicatio