RESUMO
To determine the thermal noise limit of graphene biotransistors, we have measured the complex impedance between the basal plane of single-layer graphene and an aqueous electrolyte. The impedance is dominated by an imaginary component but has a finite real component. Invoking the fluctuation-dissipation theorem, we determine the power spectral density of thermally driven voltage fluctuations at the graphene/electrolyte interface. The fluctuations have 1/f(p) dependence, with p = 0.75-0.85, and the magnitude of fluctuations scales inversely with area. Our results explain noise spectra previously measured in liquid-gated suspended graphene devices and provide realistic targets for future device performance.
Assuntos
Grafite/química , Transistores Eletrônicos , Técnicas Biossensoriais , Impedância Elétrica , Eletrólitos/química , Desenho de Equipamento , TemperaturaRESUMO
Acute respiratory failure in cystic fibrosis carries a high risk of mortality. The optimal mode of mechanical ventilation (MV) in this population is not well established. In this case series, we identified patients with cystic fibrosis who were ventilated with high-frequency percussive ventilation (HFPV) at our institution and describe their characteristics and outcomes. The use of high-frequency percussive ventilation has been sparsely described in the literature. This case series could serve as hypothesis-generating for future research.