ABSTRACT
Carbon-based nano hetero-structures are receiving increasing attention due their ability in multi-synchronous modulation of a range of mechanical and other critically desirable properties. In this paper, the vibration characteristics of two different graphene based heterostructures, graphene-hexagonal boron nitride (hBN) and graphene-molybdenum disulfide (MoS2), are explored based on atomistic finite element approach. Such vibrational characteristics of nanostructures are of utmost importance in order to access their suitability as structural members for adoption in various nano-scale devices and systems. In the current analysis, the developed atomistic finite element model for nano-heterostructures is extensively validated first with the results available in literature considering elastic responses and natural frequencies. Thereafter a range of insightful new results are presented for the dynamic behaviour of various configurations of graphene-hBN and graphene-MoS2 heterostructures including their size, chirality and boundary dependence. The investigation of tunable vibrational properties along with simultaneous modulation of other mechanical, electronic, optical, thermal and chemical attributes of such nano-heterostructures would accelerate their application as prospective candidates for manufacturing nanosensors, electromechanical resonators, and a wide range of other devices and systems across the length-scales.
ABSTRACT
Rapid-rate transcranial magnetic stimulation (rTMS) allows for the noninvasive examination of the cerebral cortex. Recent studies have begun to investigate whether rTMS may be therapeutic for the treatment of depression. In the present study, the authors report on the safety and efficacy of rTMS in treating 50 patients with refractory depression. Overall, there were 21 responders (42%). Interestingly, 56% of the young patients responded, but only 23% of the elderly patients responded to rTMS. Overall, rTMS was well tolerated in all patients. Specifically, no patient developed a new onset of seizures during rTMS. The authors discuss the extant literature on rTMS for the treatment of depression along with future areas of research.
