Effects of Mechanosensory Input on the Tracking of Pulsatile Odor Stimuli by Moth Antennal Lobe Neurons

Air turbulence ensures that in a natural environment insects tend to encounter odor stimuli in a pulsatile fashion. The frequency and duration of odor pulses varies with distance from the source, and hence successful mid-flight odor tracking requires resolution of spatiotemporal pulse dynamics. This requires both olfactory and mechanosensory input (from wind speed), a form of sensory integration observed within the antennal lobe (AL). In this work, we employ a model of the moth AL to study the effect of mechanosensory input on AL responses to pulsatile stimuli; in particular, we examine the ability of model neurons to: (1) encode the temporal length of a stimulus pulse; (2) resolve the temporal dynamics of a high frequency train of brief stimulus pulses. We find that AL glomeruli receiving olfactory input are adept at encoding the temporal length of a stimulus pulse but less effective at tracking the temporal dynamics of a pulse train, while glomeruli receiving mechanosensory input but little olfactory input can efficiently track the temporal dynamics of high frequency pulse delivery but poorly encode the duration of an individual pulse. Furthermore, we show that stronger intrinsic small-conductance calcium-dependent potassium (SK) currents tend to skew cells toward being better trackers of pulse frequency, while weaker SK currents tend to entail better encoding of the temporal length of individual pulses. We speculate a possible functional division of labor within the AL, wherein, for a particular odor, glomeruli receiving strong olfactory input exhibit prolonged spiking responses that facilitate detailed discrimination of odor features, while glomeruli receiving mechanosensory input (but little olfactory input) serve to resolve the temporal dynamics of brief, pulsatile odor encounters. Finally, we discuss how this hypothesis extends to explaining the functional significance of intraglomerular variability in observed phase II response patterns of AL neurons.

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Microstructure and mechanical properties of 2060 Al–Li alloy welded by alternating current cold metal transfer with high-frequency pulse current

High Temperature Materials and Processes ◽

10.1515/htmp-2021-0026 ◽

2021 ◽

Vol 40 (1) ◽

pp. 214-227

Author(s):

Liwei Wang ◽

Huan Hu ◽

Huan Yan ◽

Ying Liu ◽

Ziqin Wu ◽

...

Keyword(s):

Mechanical Properties ◽

Grain Size ◽

Tensile Strength ◽

Welded Joints ◽

High Frequency ◽

Pulse Current ◽

Pulse Frequency ◽

Cold Metal Transfer ◽

Cold Metal ◽

Frequency Pulse

Abstract Al–Li alloy has been widely used in the aerospace field owing to its high strength and low density. In this study, alternating current cold metal transfer (AC CMT) along with a high-frequency pulse current technique was used to weld a 2060 Al–Li alloy using an ER5356 wire. The effect of pulse frequency on the arc shape, microstructure, and mechanical properties of the welded joints was examined, and mechanical performance testing was conducted. The results revealed that the arc diameter, arc length, and arc volume showed a trend of increasing first and then decreasing with an increase in the pulse frequency and reached their peak values when the pulse frequency was 50 kHz. Coupling the welding process with a high-frequency pulse resulted in grain refinement, which was attributed to the stirring action of the arc force. Both the porosity levels and grain size decreased with increasing frequency. When the pulse frequency was 70 kHz, the porosity level was the lowest, and the grain size was refined to 24.1 μm. The tensile strength of the welded joints also increased with the pulse frequency, and a maximum tensile strength of 249 MPa was observed at 70 kHz.

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Electrophysiological aftereffects of high-frequency transcranial random noise stimulation (hf-tRNS): an EEG investigation

Experimental Brain Research ◽

10.1007/s00221-021-06142-4 ◽

2021 ◽

Author(s):

Filippo Ghin ◽

Louise O’Hare ◽

Andrea Pavan

Keyword(s):

High Frequency ◽

Discrimination Task ◽

Temporal Dynamics ◽

Random Noise ◽

Decomposition Analysis ◽

Oscillatory Activity ◽

Motion Direction ◽

Time Frequency ◽

Direction Discrimination ◽

Transcranial Random Noise Stimulation

AbstractThere is evidence that high-frequency transcranial random noise stimulation (hf-tRNS) is effective in improving behavioural performance in several visual tasks. However, so far there has been limited research into the spatial and temporal characteristics of hf-tRNS-induced facilitatory effects. In the present study, electroencephalogram (EEG) was used to investigate the spatial and temporal dynamics of cortical activity modulated by offline hf-tRNS on performance on a motion direction discrimination task. We used EEG to measure the amplitude of motion-related VEPs over the parieto-occipital cortex, as well as oscillatory power spectral density (PSD) at rest. A time–frequency decomposition analysis was also performed to investigate the shift in event-related spectral perturbation (ERSP) in response to the motion stimuli between the pre- and post-stimulation period. The results showed that the accuracy of the motion direction discrimination task was not modulated by offline hf-tRNS. Although the motion task was able to elicit motion-dependent VEP components (P1, N2, and P2), none of them showed any significant change between pre- and post-stimulation. We also found a time-dependent increase of the PSD in alpha and beta bands regardless of the stimulation protocol. Finally, time–frequency analysis showed a modulation of ERSP power in the hf-tRNS condition for gamma activity when compared to pre-stimulation periods and Sham stimulation. Overall, these results show that offline hf-tRNS may induce moderate aftereffects in brain oscillatory activity.

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Controllable Growth of Tree-Like Freestanding Electrodes Induced by High-Frequency Pulse Currents for Efficient Water Splitting and Pseudocapacitance

ACS Sustainable Chemistry & Engineering ◽

10.1021/acssuschemeng.1c01490 ◽

2021 ◽

Author(s):

Fan Zhang ◽

Renjie Ji ◽

Shuaichen Lu ◽

Yating Wang ◽

Zhijian Li ◽

...

Keyword(s):

Water Splitting ◽

High Frequency ◽

Controllable Growth ◽

Frequency Pulse

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The Effect of High Frequency Pulse on the Discharge Probability in Micro EDM

IOP Conference Series Materials Science and Engineering ◽

10.1088/1757-899x/281/1/012031 ◽

2017 ◽

Vol 281 ◽

pp. 012031

Author(s):

Y Liu ◽

Y Qu ◽

W Zhang ◽

F Ma ◽

Z Sha ◽

...

Keyword(s):

High Frequency ◽

Micro Edm ◽

Frequency Pulse

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Transfer of diclofenac sodium across excised guinea pig skin on high-frequency pulse iontophoresis. I. Equivalent circuit model.

Chemical and Pharmaceutical Bulletin ◽

10.1248/cpb.38.1019 ◽

1990 ◽

Vol 38 (4) ◽

pp. 1019-1021 ◽

Cited By ~ 7

Author(s):

Tamotsu KOIZUMI ◽

Masawa KAKEMI ◽

Kazunori KATAYAMA ◽

Hirohiko INADA ◽

Kazuyoshi SUDEJI ◽

...

Keyword(s):

Guinea Pig ◽

Equivalent Circuit ◽

High Frequency ◽

Diclofenac Sodium ◽

Equivalent Circuit Model ◽

Circuit Model ◽

Pig Skin ◽

Frequency Pulse

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Power MOSFET Linearizer of a High-Voltage Power Amplifier for High-Frequency Pulse-Echo Instrumentation

Sensors ◽

10.3390/s17040764 ◽

2017 ◽

Vol 17 (4) ◽

pp. 764 ◽

Cited By ~ 17

Author(s):

Hojong Choi ◽

Park Woo ◽

Jung-Yeol Yeom ◽

Changhan Yoon

Keyword(s):

Power Amplifier ◽

High Voltage ◽

High Frequency ◽

Power Mosfet ◽

Pulse Echo ◽

Frequency Pulse

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The Effect of HFPD Thermally Sprayed WC-Co Coatings on the Fatigue Behavior and Deformation of Al 2024-T4

Thermal Spray 2000: Proceedings from the International Thermal Spray Conference ◽

10.31399/asm.cp.itsc2000p1297 ◽

2000 ◽

Author(s):

A. Ibrahim ◽

C.C. Berndt

Keyword(s):

High Frequency ◽

High Cycle Fatigue ◽

Fatigue Behavior ◽

Cycle Fatigue ◽

Pulse Detonation ◽

Deformation Behaviors ◽

Life Distributions ◽

Thermally Sprayed ◽

Al 2024 ◽

Frequency Pulse

Abstract The effect of high frequency pulse detonation (HFPD) and HVOF thermally sprayed WC-Co coatings on the high cycle fatigue (HCF) behavior of 2024-T4 aluminum was investigated. The fatigue life distributions of specimens in the polished and coated conditions are presented as a function of the probability of failure. The monotonic and cyclic deformation behaviors of the as-received and as-coated specimens were investigated. The conclusions show that, (i) the HFPD sprayed specimens exhibited slightly higher fatigue lives compared to the uncoated specimens, (ii) the HVOF sprayed specimens exhibited significantly higher fatigue lives compared to the uncoated specimens, and (iii) the as-coated specimen was cyclically stable.

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Pulsed-DC Electrospray for Biopolymer Particle Production

MRS Proceedings ◽

10.1557/proc-1239-vv07-21 ◽

2009 ◽

Vol 1239 ◽

Author(s):

Cho-Hui Lim ◽

Kiersten R Schierbeek ◽

Michael E Mullins

Keyword(s):

Pulse Width ◽

Particle Production ◽

Pulse Amplitude ◽

Pulse Frequency ◽

Process Conditions ◽

High Duty Cycle ◽

Pulsed Dc ◽

High Pulse ◽

Long Pulse ◽

Frequency Pulse

AbstractPLLA microparticles were successfully fabricated via pulsed-DC electrospray. In this study, we investigated the effect of the pulsed voltage characteristics (e.g. pulse frequency, pulse amplitude and pulse width) on the particle’s size. We found that pulse frequency, pulse amplitude, pulse width, and the combinations of these factors had a statistically significant effect on the particle’s size. The process conditions to obtain smaller particles with uniform shape and size are a low pulse frequency, high pulse amplitude, and long pulse width (or a high duty cycle).

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