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Background: The mode of waveform generation and circuit characteristics differ between high-frequency oscillators. It is unknown if this influences performance. Objectives: To describe the relationships between set and delivered pressure amplitude (ΔP), and the interaction with frequency and endotracheal tube (ETT) diameter, in eight high-frequency oscillators. Methods: Oscillators were evaluated using a 70-ml test lung at 1.0 and 2.0 ml/cm H2O compliance, with mean airway pressures (PAW) of 10 and 20 cm H2O, frequencies of 5, 10 and 15 Hz, and an ETT diameter of 2.5 and 3.5 mm. At each permutation of PAW, frequency and ETT, the set ΔP was sequentially increased from 15 to 50 cm H2O, or from 20 to 100% maximum amplitude (10% increments) depending on the oscillator design. The ΔP at the ventilator (ΔPVENT), airway opening (ΔPAO) and within the test lung (ΔPTRACH), and tidal volume (VT) at the airway opening were determined at each set ΔP. Results: In two oscillators the relationships between set and delivered ΔP were non-linear, with a plateau in ΔP thresholds noted at all frequencies (Dräger Babylog 8000) or ≥10 Hz (Dräger VN500). In all other devices there was a linear relationship between ΔPVENT, ΔPAO and ΔPTRACH (all r2 >0.93), with differing attenuation of the pressure wave. Delivered VT at the different settings tested varied between devices, with some unable to deliver VT >3 ml at 15 Hz, and others generating VT >20 ml at 5 Hz and a 1:1 inspiratory-to-expiratory time ratio. Conclusions: Clinicians should be aware that modern high-frequency oscillators exhibit important differences in the delivered ΔP and VT.
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This paper deals with the design and performance analysis of a ring oscillator using CMOS 45nm technology process in Cadence virtuoso environment. The design of optimal Analog and Mixed Signal (AMS) very large scale integrated circuits (VLSI) is a challenging task for the integrated circuit(IC) designer. A Ring Oscillator is an active device which is made up of odd number of NOT gates and whose output oscillates between two voltage levels representing high and low. There are a number of challenges ahead while designing the CMOS Ring Oscillator which are delay, noise and glitches. CMOS is the technology of choice for many applications, CMOS oscillators with low power, phase noise and timing jitter are highly desired. In this paper, we have designed a CMOS ring oscillator with nine stages.Previously, the researchers were unable to reduce the phase noise in ring oscillators substantially with nine stages. We have successfully reduced the phase noise to -6.4kdBc/Hz at 2GHz center frequency of oscillation.
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The principle of the single-particle behaves exactly like a harmonic oscillator; but at very high frequency. The fixed static density is given at each end point of the particle, where between two, its acceleration would be extremely high. This anharmonic oscillation of the particle, work tirelessly between singularity and quantum decoherence.
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We investigate theoretically and experimentally the modulation instability process in a dispersion oscillating fiber characterized by an amplitude modulation of its group velocity dispersion. We developed an analytical model that allows us to calculate the parametric gain in these fibers and to predict the position of the quasi-phase matched modulation instability sidelobes. The two fundamental frequencies characterizing the dispersion profile lead to the splitting of the original multiple sidelobes generated in basic sinusoidally varying dispersion oscillating fibers. These theoretical predictions are confirmed by experiments.
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data is the supplementary information for this article " Robust desynchronization of Parkinson's disease pathological oscillations by frequency modulation of delayed feedback deep brain stimulation".
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The principle of the single-particle behaves exactly like a harmonic oscillator; but at very high frequency. The fixed static density is given at each end point of the particle, where between two, its acceleration would be extremely high. This anharmonic oscillation of the particle, work tirelessly between singularity and quantum decoherence.
Data Types:
  • Document
We investigate theoretically and experimentally the modulation instability process in a dispersion oscillating fiber characterized by an amplitude modulation of its group velocity dispersion. We developed an analytical model that allows us to calculate the parametric gain in these fibers and to predict the position of the quasi-phase matched modulation instability sidelobes. The two fundamental frequencies characterizing the dispersion profile lead to the splitting of the original multiple sidelobes generated in basic sinusoidally varying dispersion oscillating fibers. These theoretical predictions are confirmed by experiments.
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data is the supplementary information for this article " Robust desynchronization of Parkinson's disease pathological oscillations by frequency modulation of delayed feedback deep brain stimulation".
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Slime mould Physarum polycephalum is a single cell which physically oscillates via contraction of actomyosin in order to achieve motility. Several of its apparently ‘intelligent’ behaviour patterns such as anticipatory responses to periodic stimuli have recently been attributed as functions of the coupling between the oscillating intracellular reactions which drive its rhythmic muscular contraction, but the mechanisms that underlie these phenomena have not yet been experimentally verified. Through laboratory investigations in which we entrain the P. polycephalum plasmodium via periodic ultraviolet light exposure we find that this phenomenon is likely to result from biasing its various oscillating life processes through altering local concentration profiles of various allosteric molecules and their effectors. This temporarily overwrites the global streaming clock frequency and eradicates the wave packets usually observed in slime mould biomechanical oscillation. This response is likened to an intracellular chemical memory. We proceed to present a multi-agent model in which we demonstrate that travelling waves and oscillatory clock frequencies may emerge in the virtual organism’s biomechanical oscillator, although anticipatory responses cannot be replicated by simple mechanical interactions. We conclude by arguing that these phenomena are best characterised as analogue computation and discuss practical applications therein. The Physarum polycephalum actin network in a plasmodial tubule. SiR-actin staining, scale bar 200 μm.
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Copyright information:Taken from "Neutrophils: the forgotten cell in JIA disease pathogenesis"http://www.ped-rheum.com/content/5/1/13Pediatric Rheumatology Online Journal 2007;5():13-13.Published online 13 Jun 2007PMCID:PMC1904449. JRA patients express a small population (10–30% of the cells) that are MPO-positive and show both frequency and amplitude enhancement of NAD(P)H oscillations triggered by frequency-modulating LPS. These findings demonstrate a breakdown in the fundamental metabolic pathways regulating neutrophil oscillatory activities in JRA patients. From Jarvis et al, 2006. The authors retain the copyright for this material.
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