### 25677 results for qubit oscillator frequency

Contributors: Sven P. Heinrich, Michael Bach

Date: 2004-10-07

High-**frequency** oscillations in human visual cortex do not mirror retinal **frequencies**...High-**frequency** **oscillations**...Flash stimulation elicits oscillatory responses above 100 Hz in human visual cortex. It has been proposed that these are the result of retinal oscillations being directly relayed through the visual pathway to area V1. Experimental evidence, however, is scarce and contradictory. To address this issue, we performed a time–**frequency** analysis of simultaneously recorded retinal and cortical potentials. Matching **frequencies** would support the assumption of a direct relationship between retinal and cortical activities. In 4 of 7 subjects the **frequency** was significantly lower in the cortex than in the retina and in one subject it was significantly higher. The differences were in the range of 10–34 Hz and suggest that the cortical oscillations are not a simple echo of their retinal counterparts....Time–**frequency** distributions. On the left side, the full 20–1000 Hz range is displayed for three exemplary subjects. The two graphs per subject show the ERG and VEP activity, respectively. The high-**frequency** **oscillations** appear as a distinct area which in most cases is around or above 100 Hz. The flash was given at t=0. Those parts of the time–**frequency** diagram which would be contaminated by edge effects are displayed in white. Their spread is due to the inevitable **frequency**-dependent finite time resolution, which also causes the spurious pre-stimulus activity at low **frequencies**. The white rectangles in the diagrams mark the regions of interest, which are shown enlarged on the right side for all 7 subjects. The arrows link the high-**frequency** maxima of ERG and VEP. Most subjects produced activity around or above 100 Hz in both VEP and ERG. However, only in one subject (S1) the **frequencies** matched. Asterisks indicate the significance levels of **frequency** differences in standard notation, based on a sequential Bonferroni adjustment. No significance value could be obtained for subject S3.
...Time–**frequency** distributions. On the left side, the full 20–1000 Hz range is displayed for three exemplary subjects. The two graphs per subject show the ERG and VEP activity, respectively. The high-**frequency** oscillations appear as a distinct area which in most cases is around or above 100 Hz. The flash was given at t=0. Those parts of the time–**frequency** diagram which would be contaminated by edge effects are displayed in white. Their spread is due to the inevitable **frequency**-dependent finite time resolution, which also causes the spurious pre-stimulus activity at low **frequencies**. The white rectangles in the diagrams mark the regions of interest, which are shown enlarged on the right side for all 7 subjects. The arrows link the high-**frequency** maxima of ERG and VEP. Most subjects produced activity around or above 100 Hz in both VEP and ERG. However, only in one subject (S1) the **frequencies** matched. Asterisks indicate the significance levels of **frequency** differences in standard notation, based on a sequential Bonferroni adjustment. No significance value could be obtained for subject S3.
...High-**frequency** oscillations...Flash stimulation elicits oscillatory responses above 100 Hz in human visual cortex. It has been proposed that these are the result of retinal **oscillations** being directly relayed through the visual pathway to area V1. Experimental evidence, however, is scarce and contradictory. To address this issue, we performed a time–**frequency** analysis of simultaneously recorded retinal and cortical potentials. Matching **frequencies** would support the assumption of a direct relationship between retinal and cortical activities. In 4 of 7 subjects the **frequency** was significantly lower in the cortex than in the retina and in one subject it was significantly higher. The differences were in the range of 10–34 Hz and suggest that the cortical **oscillations** are not a simple echo of their retinal counterparts. ... Flash stimulation elicits oscillatory responses above 100 Hz in human visual cortex. It has been proposed that these are the result of retinal **oscillations** being directly relayed through the visual pathway to area V1. Experimental evidence, however, is scarce and contradictory. To address this issue, we performed a time–**frequency** analysis of simultaneously recorded retinal and cortical potentials. Matching **frequencies** would support the assumption of a direct relationship between retinal and cortical activities. In 4 of 7 subjects the **frequency** was significantly lower in the cortex than in the retina and in one subject it was significantly higher. The differences were in the range of 10–34 Hz and suggest that the cortical **oscillations** are not a simple echo of their retinal counterparts.

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Contributors: Lucas C. Monteiro, A.V. Dodonov

Date: 2016-04-08

Anti-dynamical Casimir effect with an ensemble of **qubits**...We consider the interaction between a single cavity mode and N≫1 identical **qubits**, assuming that any system parameter can be rapidly modulated in situ by external bias. It is shown that, for the **qubits** initially in the ground states, three photons can be coherently annihilated in the dispersive regime for harmonic modulation with **frequency** 3ω0−Ω0, where ω0 (Ω0) is the bare cavity (**qubit**) **frequency**. This phenomenon can be called “Anti-dynamical Casimir effect”, since a pair of excitations is destroyed without dissipation due to the external modulation. For the initial vacuum cavity state, three **qubit** excitations can also be annihilated for the modulation **frequency** 3Ω0−ω0. ... We consider the interaction between a single cavity mode and N≫1 identical **qubits**, assuming that any system parameter can be rapidly modulated in situ by external bias. It is shown that, for the **qubits** initially in the ground states, three photons can be coherently annihilated in the dispersive regime for harmonic modulation with **frequency** 3ω0−Ω0, where ω0 (Ω0) is the bare cavity (**qubit**) **frequency**. This phenomenon can be called “Anti-dynamical Casimir effect”, since a pair of excitations is destroyed without dissipation due to the external modulation. For the initial vacuum cavity state, three **qubit** excitations can also be annihilated for the modulation **frequency** 3Ω0−ω0.

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Contributors: Uwe Starossek

Date: 2015-01-01

Free **oscillation** response of pendulum mechanism.
...Free **oscillation** response...Low **frequency**...A low-**frequency** pendulum mechanism...A pendulum mechanism is presented whose natural **frequency** of **oscillation** is distinctly lower than that of a conventional pendulum of comparable size. Furthermore, its natural **frequency** is approximately proportional to its amplitude of **oscillation**. The mechanism can thus be tuned to extremely low **frequencies** by using small amplitudes. The undamped free **oscillation** response of the mechanism is studied. The derivation of the equation of motion is outlined for both large and, after neglecting higher order terms, small displacements. In both cases, a second-order nonlinear differential equation results. When higher order terms are neglected, the equation of motion is of simple form and can be solved symbolically in terms of a Jacobi elliptic function. Based on this solution, a closed-form expression for the natural **frequency** is derived and the characteristics of the free **oscillation** response are discussed....A pendulum mechanism is presented whose natural **frequency** of oscillation is distinctly lower than that of a conventional pendulum of comparable size. Furthermore, its natural **frequency** is approximately proportional to its amplitude of oscillation. The mechanism can thus be tuned to extremely low **frequencies** by using small amplitudes. The undamped free oscillation response of the mechanism is studied. The derivation of the equation of motion is outlined for both large and, after neglecting higher order terms, small displacements. In both cases, a second-order nonlinear differential equation results. When higher order terms are neglected, the equation of motion is of simple form and can be solved symbolically in terms of a Jacobi elliptic function. Based on this solution, a closed-form expression for the natural **frequency** is derived and the characteristics of the free oscillation response are discussed. ... A pendulum mechanism is presented whose natural **frequency** of **oscillation** is distinctly lower than that of a conventional pendulum of comparable size. Furthermore, its natural **frequency** is approximately proportional to its amplitude of **oscillation**. The mechanism can thus be tuned to extremely low **frequencies** by using small amplitudes. The undamped free **oscillation** response of the mechanism is studied. The derivation of the equation of motion is outlined for both large and, after neglecting higher order terms, small displacements. In both cases, a second-order nonlinear differential equation results. When higher order terms are neglected, the equation of motion is of simple form and can be solved symbolically in terms of a Jacobi elliptic function. Based on this solution, a closed-form expression for the natural **frequency** is derived and the characteristics of the free **oscillation** response are discussed.

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Contributors: Atsushi Tomeda, Shogo Morisaki, Kenichi Watanabe, Shigeki Kuroki, Isao Ando

Date: 2003-07-24

The plots of 1H signal width for the crystalline region of polyethylene thin film on the surface of on an piezoelectric **oscillator** plate against **oscillation** **frequency** in the range from 1 Hz to 2 MHz (a) and in the expanded range from 1 Hz to 100 kHz (b) at 40 °C.
...The plots of 1H signal width for the crystalline region of polyethylene thin film on the surface of on an piezoelectric **oscillator** plate against oscillation **frequency** in the range from 1 Hz to 2 MHz (a) and in the expanded range from 1 Hz to 100 kHz (b) at 40 °C.
...The plots of 1H signal width for the non-crystalline region of polyethylene thin film on the surface of on a piezoelectric **oscillator** plate against **oscillation** **frequency** in the range from 1 Hz to 2 MHz (a) in the expanded range from 1 Hz to 100 kHz (b) at 40 °C.
...The plots of 1H signal width for the non-crystalline region of polyethylene thin film on the surface of on a piezoelectric **oscillator** plate against oscillation **frequency** in the range from 1 Hz to 2 MHz (a) in the expanded range from 1 Hz to 100 kHz (b) at 40 °C.
...A diagram of an NMR glass tube with an piezoelectric **oscillator** plate. The polyethylene thin film was molten and adhered on the surface of piezoelectric **oscillator** plate. The **oscillation** of an piezoelectric **oscillator** plate is generated by AD alternator.
...The 1H NMR spectrum of polyethylene thin film on an piezoelectric **oscillator** plate made of inorganic material was observed, which is oscillated with high **frequency** by application of AD electric current in the Hz–MHz range. From these experimental results, it is shown that dipolar interactions in solid polyethylene are remarkably reduced by high **frequency** oscillation and then the signal width of the crystalline component is significantly reduced with an increase in oscillation **frequency**. This means that the introduction of the high **frequency** oscillation for solids has large potentiality of obtaining the high resolution NMR spectrum....1H NMR signal narrowing of solid polymer by high **frequency** oscillation...A diagram of an NMR glass tube with an piezoelectric **oscillator** plate. The polyethylene thin film was molten and adhered on the surface of piezoelectric **oscillator** plate. The oscillation of an piezoelectric **oscillator** plate is generated by AD alternator.
...The 1H NMR spectrum of polyethylene thin film on an piezoelectric **oscillator** plate made of inorganic material was observed, which is **oscillated** with high **frequency** by application of AD electric current in the Hz–MHz range. From these experimental results, it is shown that dipolar interactions in solid polyethylene are remarkably reduced by high **frequency** **oscillation** and then the signal width of the crystalline component is significantly reduced with an increase in **oscillation** **frequency**. This means that the introduction of the high **frequency** **oscillation** for solids has large potentiality of obtaining the high resolution NMR spectrum. ... The 1H NMR spectrum of polyethylene thin film on an piezoelectric **oscillator** plate made of inorganic material was observed, which is **oscillated** with high **frequency** by application of AD electric current in the Hz–MHz range. From these experimental results, it is shown that dipolar interactions in solid polyethylene are remarkably reduced by high **frequency** **oscillation** and then the signal width of the crystalline component is significantly reduced with an increase in **oscillation** **frequency**. This means that the introduction of the high **frequency** **oscillation** for solids has large potentiality of obtaining the high resolution NMR spectrum.

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Contributors: Howan Leung, Cannon X.L. Zhu, Danny T.M. Chan, Wai S. Poon, Lin Shi, Vincent C.T. Mok, Lawrence K.S. Wong

Date: 2015-01-01

An example of the implantation schedule (patient #7) demonstrating areas with conventional frequency ictal patterns, ictal high-frequency oscillations, hyperexcitability, and radiological lesions.
...High-**frequency** oscillations (HFOs, 80–500Hz) from intracranial electroencephalography (EEG) may represent a biomarker of epileptogenicity for epilepsy. We explored the relationship between ictal HFOs and hyperexcitability with a view to improving surgical outcome....High-**frequency** **oscillations**...An example of the implantation schedule (patient #1) demonstrating areas with conventional **frequency** ictal patterns, ictal high-**frequency** **oscillations**, hyperexcitability, and radiological lesions.
...Summary table for statistical analysis. HFO=high frequency oscillations, CFIP=conventional frequency ictal patterns.
...An example of the implantation schedule (patient #7) demonstrating areas with conventional **frequency** ictal patterns, ictal high-**frequency** **oscillations**, hyperexcitability, and radiological lesions.
...High-**frequency** **oscillations** (HFOs, 80–500Hz) from intracranial electroencephalography (EEG) may represent a biomarker of epileptogenicity for epilepsy. We explored the relationship between ictal HFOs and hyperexcitability with a view to improving surgical outcome....Ictal high-**frequency** oscillations and hyperexcitability in refractory epilepsy...An example of the implantation schedule (patient #1) demonstrating areas with conventional frequency ictal patterns, ictal high-frequency oscillations, hyperexcitability, and radiological lesions.
...High-**frequency** oscillations...Summary table for statistical analysis. HFO=high **frequency** **oscillations**, CFIP=conventional **frequency** ictal patterns.
... High-**frequency** **oscillations** (HFOs, 80–500Hz) from intracranial electroencephalography (EEG) may represent a biomarker of epileptogenicity for epilepsy. We explored the relationship between ictal HFOs and hyperexcitability with a view to improving surgical outcome.

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Contributors: M.E. Leser, S. Acquistapace, A. Cagna, A.V. Makievski, R. Miller

Date: 2005-07-01

Apparent dilational elasticity modulus as a function of **oscillation** **frequency** for drops of water (♦), water/ethanol 86:14 (■), ethanol (▴), amplitude of volume **oscillations** 8%.
...Apparent dilational elasticity modulus as a function of oscillation **frequency** for drops of water (♦), water/ethanol 86:14 (■), ethanol (▴), amplitude of volume oscillations 8%.
...**Oscillating** drops and bubbles...Apparent dilational elasticity modulus as a function of oscillation **frequency** for drops of water (♦), water/ethanol 86:14 (■), ethanol (▴), amplitude of volume oscillations 2%.
...Apparent dilational elasticity modulus as a function of **oscillation** **frequency** for drops of silicon oil (●), paraffin oil (■), amplitude of volume **oscillations** 2%.
...Limiting **frequency**...Apparent dilational elasticity modulus as a function of **oscillation** **frequency** for drops of water (♦), water/ethanol 86:14 (■), ethanol (▴), amplitude of volume **oscillations** 2%.
...Limits of oscillation **frequencies** in drop and bubble shape tensiometry...Apparent dilational elasticity modulus as a function of oscillation **frequency** for drops of silicon oil (●), paraffin oil (■), amplitude of volume oscillations 2%.
...Surface tension and apparent dilational elasticity modulus E as a function of **oscillation** **frequency** for an air bubble in pure water.
...Surface tension and apparent dilational elasticity modulus E as a function of **oscillation** **frequency** for a drop of pure water in air.
...Surface tension and apparent dilational elasticity modulus E as a function of oscillation **frequency** for an air bubble in pure water.
...To determine the dilational rheology of surface layers, the profile analysis tensiometry can be used with oscillating drops or bubbles. The methodology limits for these oscillations depend on the liquids’ properties, such as density, viscosity and surface tension. For the most frequently studied water/air interface, the maximum oscillation **frequency** is of the order of 1Hz, although much higher **frequencies** are technically feasible by the existing profile analysis tensiometers. For f>1Hz, deviations of the drops/bubbles from the Laplacian shape mimic non-zero dilational elasticities for the pure water/air and ethanol/air interface. For liquids of higher viscosity, the critical **frequency** is much lower....Surface tension and apparent dilational elasticity modulus E as a function of oscillation **frequency** for a drop of pure water in air.
...To determine the dilational rheology of surface layers, the profile analysis tensiometry can be used with **oscillating** drops or bubbles. The methodology limits for these **oscillations** depend on the liquids’ properties, such as density, viscosity and surface tension. For the most frequently studied water/air interface, the maximum **oscillation** **frequency** is of the order of 1Hz, although much higher **frequencies** are technically feasible by the existing profile analysis tensiometers. For f>1Hz, deviations of the drops/bubbles from the Laplacian shape mimic non-zero dilational elasticities for the pure water/air and ethanol/air interface. For liquids of higher viscosity, the critical **frequency** is much lower. ... To determine the dilational rheology of surface layers, the profile analysis tensiometry can be used with **oscillating** drops or bubbles. The methodology limits for these **oscillations** depend on the liquids’ properties, such as density, viscosity and surface tension. For the most frequently studied water/air interface, the maximum **oscillation** **frequency** is of the order of 1Hz, although much higher **frequencies** are technically feasible by the existing profile analysis tensiometers. For f>1Hz, deviations of the drops/bubbles from the Laplacian shape mimic non-zero dilational elasticities for the pure water/air and ethanol/air interface. For liquids of higher viscosity, the critical **frequency** is much lower.

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Contributors: György Buzsáki, Fernando Lopes da Silva

Date: 2012-09-01

Spontaneously occurring fast ‘ripple’ **oscillations** (400–500Hz) in the neocortex of the rat during high-voltage spindles. (A) Averaged high-voltage spindles and associated unit firing histograms from layers IV–VI. (B) Wide-band (a and a′; 1Hz–5kHz), filtered field (b and b′; 200–800Hz), and filtered unit (c and c′; 0.5–5kHz) traces from layers IV and V, respectively. (C) Averaged fast waves and corresponding unit histograms. The field ripples are filtered (200–800Hz) derivatives of the wide-band signals recorded from 16 sites. Note the sudden phase-reversal of the **oscillating** waves (arrows) but locking of unit discharges (dashed lines). These phase reversed dipoles likely reflect synchronous discharge of layer 5 neurons in the vicinity of the recording electrode.
...High **frequency** oscillations in the intact brain...Self-organized burst of activity in the CA3 region of the hippocampus produces a sharp wave sink in the apical dendrites of CA1 pyramidal neurons and also discharge interneurons. The interactions between the discharging pyramidal cells and interneurons give rise to a short-lived fast **oscillation** (‘ripple’; 140–200Hz), which can be detected as a field potential in the somatic layer. The strong CA1 population burst brings about strongly synchronized activity in the target populations of parahippocampal structures as well. These parahippocampal ripples are slower and less synchronous, compared to CA1 ripples.
...High **frequency** **oscillations** (HFOs) constitute a novel trend in neurophysiology that is fascinating neuroscientists in general, and epileptologists in particular. But what are HFOs? What is the **frequency** range of HFOs? Are there different types of HFOs, physiological and pathological? How are HFOs generated? Can HFOs represent temporal codes for cognitive processes? These questions are pressing and this symposium volume attempts to give constructive answers. As a prelude to this exciting discussion, we summarize the physiological high **frequency** patterns in the intact brain, concentrating mainly on hippocampal patterns, where the mechanisms of high **frequency** **oscillations** are perhaps best understood....High **frequency** oscillations (HFOs) constitute a novel trend in neurophysiology that is fascinating neuroscientists in general, and epileptologists in particular. But what are HFOs? What is the **frequency** range of HFOs? Are there different types of HFOs, physiological and pathological? How are HFOs generated? Can HFOs represent temporal codes for cognitive processes? These questions are pressing and this symposium volume attempts to give constructive answers. As a prelude to this exciting discussion, we summarize the physiological high **frequency** patterns in the intact brain, concentrating mainly on hippocampal patterns, where the mechanisms of high **frequency** oscillations are perhaps best understood. ... High **frequency** **oscillations** (HFOs) constitute a novel trend in neurophysiology that is fascinating neuroscientists in general, and epileptologists in particular. But what are HFOs? What is the **frequency** range of HFOs? Are there different types of HFOs, physiological and pathological? How are HFOs generated? Can HFOs represent temporal codes for cognitive processes? These questions are pressing and this symposium volume attempts to give constructive answers. As a prelude to this exciting discussion, we summarize the physiological high **frequency** patterns in the intact brain, concentrating mainly on hippocampal patterns, where the mechanisms of high **frequency** **oscillations** are perhaps best understood.

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Contributors: Fatema F. Ghasia, Aasef G. Shaikh

Date: 2014-01-01

Most common eye movements, oblique saccades, feature rapid velocity, precise amplitude, but curved trajectory that is variable from trial-to-trial. In addition to curvature and inter-trial variability, the oblique saccade trajectory also features high-**frequency** oscillations. A number of studies proposed the physiological basis of the curvature and inter-trial variability of the oblique saccade trajectory, but kinematic characteristics of high-**frequency** oscillations are yet to be examined. We measured such oscillations and compared their properties with orthogonal pure horizontal and pure vertical oscillations generated during pure vertical and pure horizontal saccades, respectively. We found that the **frequency** of oscillations during oblique saccades ranged between 15 and 40 Hz, consistent with the **frequency** of orthogonal saccadic oscillations during pure horizontal or pure vertical saccades. We also found that the amplitude of oblique saccade oscillations was larger than pure horizontal and pure vertical saccadic oscillations. These results suggest that the superimposed high-**frequency** sinusoidal oscillations upon the oblique saccade trajectory represent reverberations of disinhibited circuit of reciprocally innervated horizontal and vertical burst generators....(A) Comparison of the frequency of oscillations during oblique, pure horizontal and pure vertical saccades. Number of observations is plotted on y-axis, while x-axis represents bins of oscillation frequency. Each data point represents the number of observations in a given frequency bin. Black trace suggests oblique saccade, Gray traces with circular symbols are horizontal saccades and triangular symbols represent vertical saccade. Dashed lines depict median oscillation frequency. (B) Comparison of frequency oblique saccade oscillations with the frequency of orthogonal saccadic oscillations during pure horizontal and vertical saccades. Each data point depicts one subject. Black data points are comparison with pure horizontal saccade, gray data points are comparison with vertical saccade. Dashed gray line is an equality line. (C) Comparison of the amplitude of the sinusoidal modulation of oblique, horizontal, and vertical saccade trajectories. Number of samples is plotted on y-axis, while x-axis represents the amplitude bins. Each data point depicts number of observations in a given bin of the histogram. Black trace shows oblique saccade, Gray trace with circuit symbol is a horizontal saccade and the triangular symbol is a vertical saccade. Dashed lines represent median values.
...(A) Comparison of the **frequency** of **oscillations** during oblique, pure horizontal and pure vertical saccades. Number of observations is plotted on y-axis, while x-axis represents bins of **oscillation** **frequency**. Each data point represents the number of observations in a given **frequency** bin. Black trace suggests oblique saccade, Gray traces with circular symbols are horizontal saccades and triangular symbols represent vertical saccade. Dashed lines depict median **oscillation** **frequency**. (B) Comparison of **frequency** oblique saccade **oscillations** with the **frequency** of orthogonal saccadic **oscillations** during pure horizontal and vertical saccades. Each data point depicts one subject. Black data points are comparison with pure horizontal saccade, gray data points are comparison with vertical saccade. Dashed gray line is an equality line. (C) Comparison of the amplitude of the sinusoidal modulation of oblique, horizontal, and vertical saccade trajectories. Number of samples is plotted on y-axis, while x-axis represents the amplitude bins. Each data point depicts number of observations in a given bin of the histogram. Black trace shows oblique saccade, Gray trace with circuit symbol is a horizontal saccade and the triangular symbol is a vertical saccade. Dashed lines represent median values.
...Most common eye movements, oblique saccades, feature rapid velocity, precise amplitude, but curved trajectory that is variable from trial-to-trial. In addition to curvature and inter-trial variability, the oblique saccade trajectory also features high-**frequency** **oscillations**. A number of studies proposed the physiological basis of the curvature and inter-trial variability of the oblique saccade trajectory, but kinematic characteristics of high-**frequency** **oscillations** are yet to be examined. We measured such **oscillations** and compared their properties with orthogonal pure horizontal and pure vertical **oscillations** generated during pure vertical and pure horizontal saccades, respectively. We found that the **frequency** of **oscillations** during oblique saccades ranged between 15 and 40 Hz, consistent with the **frequency** of orthogonal saccadic **oscillations** during pure horizontal or pure vertical saccades. We also found that the amplitude of oblique saccade **oscillations** was larger than pure horizontal and pure vertical saccadic **oscillations**. These results suggest that the superimposed high-**frequency** sinusoidal **oscillations** upon the oblique saccade trajectory represent reverberations of disinhibited circuit of reciprocally innervated horizontal and vertical burst generators....Source of high-**frequency** oscillations in oblique saccade trajectory...An example of horizontal, vertical, and oblique saccade from one healthy subject. The left column depicts horizontal saccade; central column vertical, and right column is oblique saccade. Panels A, B and C illustrate eye position vector plotted along y-axis. Panels D, E and F represent eye velocity vector plotted along y-axis while ordinate in panels G, H and I illustrate eye acceleration. In each panel, x-axis represents corresponding time. Arrows in panels C, F, I show **oscillations** in oblique saccade trajectory.
... Most common eye movements, oblique saccades, feature rapid velocity, precise amplitude, but curved trajectory that is variable from trial-to-trial. In addition to curvature and inter-trial variability, the oblique saccade trajectory also features high-**frequency** **oscillations**. A number of studies proposed the physiological basis of the curvature and inter-trial variability of the oblique saccade trajectory, but kinematic characteristics of high-**frequency** **oscillations** are yet to be examined. We measured such **oscillations** and compared their properties with orthogonal pure horizontal and pure vertical **oscillations** generated during pure vertical and pure horizontal saccades, respectively. We found that the **frequency** of **oscillations** during oblique saccades ranged between 15 and 40 Hz, consistent with the **frequency** of orthogonal saccadic **oscillations** during pure horizontal or pure vertical saccades. We also found that the amplitude of oblique saccade **oscillations** was larger than pure horizontal and pure vertical saccadic **oscillations**. These results suggest that the superimposed high-**frequency** sinusoidal **oscillations** upon the oblique saccade trajectory represent reverberations of disinhibited circuit of reciprocally innervated horizontal and vertical burst generators.

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Contributors: Hitoshi Mochizuki, Yoshikazu Ugawa, Katsuyuki Machii, Yasuo Terao, Ritsuko Hanajima, Toshiaki Furubayashi, Haruo Uesugi, Ichiro Kanazawa

Date: 1999-01-01

Somatosensory evoked potentials of a normal subject. Two SEPs are superimposed in a single trace. A few small notches were seen on the ascending slope of N20 in raw SEPs (A). The onset of N20 component was 15.7 ms (dotted line). **Oscillation** potentials were clearly detectable and their amplitudes were measurable in SEPs filtered at 500 to 1000 Hz (B). Three potentials (indicated by arrows) were judged as significant (larger than 3 times mean amplitude range of background recordings) peaks of an **oscillation**.
...The amplitudes of **oscillation** potentials (A) and their size ratios to the main components of SEP (B,C) were plotted against the groups of their onset latencies. (•, controls; ○, Parkinson's disease; ×, myoclonus epilepsy). The latencies for the 1st to 10th groups were 0.0–1.2, 1.3–2.5, 2.6–3.9, 4.0–5.3, 5.4–7.0, 7.1–8.7, 8.8–10.4, 10.5–12.1, 12.2–12.8 and 12.9–14.5 ms. The amplitudes of **oscillation** potentials are shown in (A), the ratio of the amplitude of **oscillation** potential to that of N20o-N20p [ratio (osc/N20o-N20p)] in (B), and the ratio of **oscillation** potential to N20p-P25p [ratio (osc/N20p-N25p)] in (C). (A) In PD patients, the sizes of some **oscillation** potentials were abnormally larger than the normal **oscillation** potentials in the first to sixth groups. In contrast, in patients with ME, extremely enlarged **oscillations** were observed in the fourth to tenth groups. (B) The ratios (osc/N20o-N20p) for abnormally enlarged **oscillation** potentials were significantly larger than the normal values in both patients with PD and ME. (C) In PD patients, the ratios (osc/N20p-P25p) for enlarged **oscillation** peaks were again abnormally larger than the normal values. In ME patients, however, those for enlarged potentials were the same as the normal values for earlier (1st to 5th) group **oscillation** potentials. In patients with ME, **oscillation** potentials were present at late latencies when they were never seen in normal subjects.
...High-**frequency** oscillation...High-**frequency** **oscillation**...SEPs of a patient with Parkinson's disease. Several notches were clearly seen on the ascending and descending slopes of N20 even in conventional SEPs (A). The onset of N20 (14.4 ms) following the end of P14 subcortical component is shown by a dashed line. Six **oscillation** potentials (indicated by arrows) followed P14 in highly filtered (500–1000 Hz) SEPs (B). Four of them (indicated by large arrows) were abnormally enlarged (>mean+3 SD of normal values). This patient was considered to have a giant **oscillation**.
...Aim: A high-**frequency** **oscillation** in the range of 600–900 Hz has been shown to be a component of the somatosensory evoked potential (SEP) in humans. In the present communication, we studied these **oscillation** potentials in two neurological disorders....Aim: A high-**frequency** oscillation in the range of 600–900 Hz has been shown to be a component of the somatosensory evoked potential (SEP) in humans. In the present communication, we studied these oscillation potentials in two neurological disorders....Histograms of the onset latencies of **oscillation** potentials in normal subjects (A) and Parkinson's disease patients (B). There were five groups in the onset latencies of **oscillation** potentials in normal subjects (A). In patients with Parkinson's disease, **oscillation** potentials were observed at almost the same latency groups as normals (B).
...Somatosensory evoked high-**frequency** oscillation in Parkinson's disease and myoclonus epilepsy...SEPs of a patient with myoclonus epilepsy (ME). In conventional SEPs (A), the latencies of N20, P25 and N33 components were within the normal range even though the N20-P25 and P25-N33 amplitudes were extremely enlarged. Several **oscillation** potentials were seen on the slope from P25 to N33 and descending slope of N33. Clearly differentiated 9 **oscillation** potentials (arrows) were detected in SEPs filtered 500–1000 Hz (B). Seven of them (third to ninth potentials) were abnormally large (large arrows). The onset of sixth potential was 8.9 ms. The last 4 **oscillation** potentials were evoked at the latencies when no **oscillation** potentials were observed in normals.
... Aim: A high-**frequency** **oscillation** in the range of 600–900 Hz has been shown to be a component of the somatosensory evoked potential (SEP) in humans. In the present communication, we studied these **oscillation** potentials in two neurological disorders.

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Contributors: Wolfgang Winkler, Johannes Borngräber, Bernd Heinemann

Date: 2005-02-01

Photograph of the **oscillator** chip.
...A 117GHz LC-**oscillator** in SiGe:C BiCMOS technology...In this paper a voltage-controlled **oscillator** (VCO) is presented reaching oscillation **frequencies** well above 100GHz. The **oscillator** has been fabricated in a 200GHz SiGe:C BiCMOS technology with 0.25μm minimum feature size. In the design of the VCO two circuit approaches were considered. The first used transmission- lines in the resonator and the second used inductors above the silicon substrate. It is shown by simulation that by using inductors a higher oscillation **frequency** can be obtained. The fabricated **oscillator** has a tuning range from 113.2 to 117.2GHz at a supply voltage of −3V. This oscillation **frequency** is the highest reported so far for a silicon-based transistor technology....Tuning curve of the LC **oscillator**.
...In this paper a voltage-controlled **oscillator** (VCO) is presented reaching **oscillation** **frequencies** well above 100GHz. The **oscillator** has been fabricated in a 200GHz SiGe:C BiCMOS technology with 0.25μm minimum feature size. In the design of the VCO two circuit approaches were considered. The first used transmission- lines in the resonator and the second used inductors above the silicon substrate. It is shown by simulation that by using inductors a higher **oscillation** **frequency** can be obtained. The fabricated **oscillator** has a tuning range from 113.2 to 117.2GHz at a supply voltage of −3V. This **oscillation** **frequency** is the highest reported so far for a silicon-based transistor technology....Simulation results and measurement of the 117GHz **oscillator** (VEE=-3V)
...Circuit diagram of the high **frequency** **oscillator**.
...LC-**oscillator**...Circuit diagram of the high frequency **oscillator**.
... In this paper a voltage-controlled **oscillator** (VCO) is presented reaching **oscillation** **frequencies** well above 100GHz. The **oscillator** has been fabricated in a 200GHz SiGe:C BiCMOS technology with 0.25μm minimum feature size. In the design of the VCO two circuit approaches were considered. The first used transmission- lines in the resonator and the second used inductors above the silicon substrate. It is shown by simulation that by using inductors a higher **oscillation** **frequency** can be obtained. The fabricated **oscillator** has a tuning range from 113.2 to 117.2GHz at a supply voltage of −3V. This **oscillation** **frequency** is the highest reported so far for a silicon-based transistor technology.

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