scholarly journals High-Frequency Generation of Transgenic Zebrafish Which Reliably Express GFP in Whole Muscles or the Whole Body by Using Promoters of Zebrafish Origin

1997 ◽  
Vol 192 (2) ◽  
pp. 289-299 ◽  
Author(s):  
Shin-ichi Higashijima ◽  
Hitoshi Okamoto ◽  
Naoto Ueno ◽  
Yoshiki Hotta ◽  
Goro Eguchi
Keyword(s):  
High Frequency ◽  
Whole Body ◽  
Transgenic Zebrafish ◽  
Frequency Generation

Optimal frequency of whole body vibration training for improving balance and physical performance in the older people with chronic stroke: A randomized controlled trial

2021 ◽  
pp. 026921552110505
Author(s):  
Ning Wei ◽  
Mengying Cai
Keyword(s):  
Older People ◽  
Physical Performance ◽  
High Frequency ◽  
Low Frequency ◽  
Chronic Stroke ◽  
Whole Body ◽  
Timed Up And Go ◽  
Stand Test ◽  
Sit To Stand ◽  
Frequency Group

Objective To explore the optimal frequency of whole-body vibration training for improving the balance and physical performance in older people with chronic stroke. Design a single-blind randomized controlled trial. Setting Two rehabilitation units in the Wuhan Brain Hospital in China. Participants A total of 78 seniors with chronic stroke. Interventions Low-frequency group (13 Hz), high-frequency group (26 Hz), and zero-frequency group (Standing on the vibration platform with 0 Hz) for 10 sessions of side-alternating WBV training. Main measures The timed-up-and-go test, five-repetition sit-to-stand test, 10-metre walking test, and Berg balance scale were assessed pre- and post-intervention. Results Significant time × group interaction effects in five-repetition sit-to-stand test (p = 0.014) and timed-up-and-go test at self-preferred speed (p = 0.028) were observed. The high-frequency group outperformed the zero-frequency group in both five-repetition sit-to-stand test (p = 0.039) and timed-up-and-go test at self-preferred speed (p = 0.024) after 10-sessions training. The low-frequency group displayed only a significant improvement in five-repetition sit-to-stand test after training (p = 0.028). No significant within- or between-group changes were observed in the Berg balance scale and walking speed (p > 0.05). No significant group-difference were found between low-frequency and high-frequency groups. No adverse events were reported during study. Conclusions Compared with 13 Hz, 26 Hz had no more benefits on balance and physical performance in older people with chronic stroke.

Vestibuloocular Reflex Dynamics During High-Frequency and High-Acceleration Rotations of the Head on Body in Rhesus Monkey

2002 ◽  
Vol 88 (1) ◽  
pp. 13-28 ◽  
Author(s):  
Marko Huterer ◽  
Kathleen E. Cullen
Keyword(s):  
Eye Movements ◽  
High Frequency ◽  
The Body ◽  
Whole Body ◽  
Head Motion ◽  
Similar Response ◽  
Vestibuloocular Reflex ◽  
Frequency Range ◽  
Response Dynamics ◽  
Passive Rotation

For frequencies >10 Hz, the vestibuloocular reflex (VOR) has been primarily investigated during passive rotations of the head on the body in humans. These prior studies suggest that eye movements lag head movements, as predicted by a 7-ms delay in the VOR reflex pathways. However, Minor and colleagues recently applied whole-body rotations of frequencies ≤15 Hz in monkeys and found that eye movements were nearly in phase with head motion across all frequencies. The goal of the present study was to determine whether VOR response dynamics actually differ significantly for whole-body versus head-on-body rotations. To address this question, we evaluated the gain and phase of the VOR induced by high-frequency oscillations of the head on the body in monkeys by directly measuring both head and eye movements using the magnetic search coil technique. A torque motor was used to rotate the heads of three Rhesus monkeys over the frequency range 5–25 Hz. Peak head velocity was held constant, first at ±50°/s and then ±100°/s. The VOR was found to be essentially compensatory across all frequencies; gains were near unity (1.1 at 5 Hz vs. 1.2 at 25 Hz), and phase lag increased only slightly with frequency (from 2° at 5 Hz to 11° at 25 Hz, a marked contrast to the 63° lag at 25 Hz predicted by a 7-ms VOR latency). Furthermore, VOR response dynamics were comparable in darkness and when viewing a target and did not vary with peak velocity. Although monkeys offered less resistance to the initial cycles of applied head motion, the gain and phase of the VOR did not vary for early versus late cycles, suggesting that an efference copy of the motor command to the neck musculature did not alter VOR response dynamics. In addition, VOR dynamics were also probed by applying transient head perturbations with much greater accelerations (peak acceleration >15,000°/s2) than have been previously employed. The VOR latency was between 5 and 6 ms, and mean gain was close to unity for two of the three animals tested. A simple linear model well described the VOR responses elicited by sinusoidal and transient head on body rotations. We conclude that the VOR is compensatory over a wide frequency range in monkeys and has similar response dynamics during passive rotation of the head on body as during passive rotation of the whole body in space.

High Frequency Generation Based-On Nonlinear Micro Ring Resonator for Frequency Band Enhancement

2014 ◽  
Vol 979 ◽  
pp. 508-511
Author(s):  
Pongputhai Udomariyasap ◽  
Suthichai Noppanakeepong ◽  
Nithiroth Pornsuwancharoen
Keyword(s):  
Channel Capacity ◽  
Optical Communication ◽  
High Frequency ◽  
Ring Resonator ◽  
Ring Resonators ◽  
Small Device ◽  
Specific Frequency ◽  
Frequency Generation ◽  
Resonator System ◽  
Signal Filter

Propose the simulation of THz carrier frequencies using the small device and a Gaussian beam propagating within the device system. We found that the generated output power with the high frequency can be achieved. This consisted of a serial nonlinear micro ring resonator system for generating pulse and signal filter by Add/Drop filter, a technology optical communication by the micro ring resonator which generates the THz frequency multiple, whereas channel capacity in term of multi frequency bands can be provided by optical Add/Drop multiplexing. The increase in the number of channel capacity can be obtained by the increase in frequency density, while the security was introduced by the specific frequency filter, which was operated by the central operator. The optical micro ring resonators for THz frequency generation and enhancement are reviewed. The advantage of proposed system can be implemented by using the simultaneous optical communication system.

scholarly journals Fluoropolymer surface coatings to control droplets in microfluidic devices

Lab on a Chip ◽  
2014 ◽  
Vol 14 (11) ◽  
pp. 1834-1841 ◽  
Author(s):  
Carson T. Riche ◽  
Chuchu Zhang ◽  
Malancha Gupta ◽  
Noah Malmstadt
Keyword(s):  
High Frequency ◽  
Microfluidic Devices ◽  
Surface Coatings ◽  
Frequency Generation

Vapor deposited fluoropolymer coatings enabled extraction-induced merging of droplets and high frequency generation of droplets within PDMS microfluidic devices.

High frequency generation of coupled GHI and DNI based on clustered Dynamic Paths

Solar Energy ◽  
2018 ◽  
Vol 159 ◽  
pp. 453-457 ◽  
Author(s):  
Carlos F. Peruchena ◽  
Miguel Larrañeta ◽  
Manuel Blanco ◽  
Ana Bernardos
Keyword(s):  
High Frequency ◽  
Frequency Generation

scholarly journals Prevalence of Vestibular Disorders in Independent People Over 50 That Experience Dizziness

2021 ◽  
Vol 12 ◽  
Author(s):  
William V. C. Figtree ◽  
Jasmine C. Menant ◽  
Allan T. Chau ◽  
Patrick P. Hübner ◽  
Stephen R. Lord ◽  
...  
Keyword(s):  
Time Constant ◽  
High Frequency ◽  
Constant Velocity ◽  
Vestibular Function ◽  
Community Dwelling ◽  
Whole Body ◽  
Head Impulse Test ◽  
Vestibular Loss ◽  
Vestibulo Ocular Reflex ◽  
The Impact

People aged over 50 are the most likely to present to a physician for dizziness. It is important to identify the main cause of dizziness in order to develop the best treatment approach. Our goal was to determine the prevalence of benign paroxysmal positional vertigo (BPPV), and peripheral and central vestibular function in people that had experienced dizziness within the past year aged over 50. One hundred and ninety three community-dwelling participants aged 51–92 (68 ± 8.7 years; 117 females) were tested using the clinical and video head impulse test (cHIT and vHIT) to test high-frequency vestibular organ function; the head thrust dynamic visual acuity (htDVA) test to test high-frequency visual-stability; the dizziness handicap inventory (DHI) to measure the impact of dizziness; as well as sinusoidal and unidirectional rotational chair testing to test low- to mid-frequency peripheral and central vestibular function. From these assessments we computed the following measures: HIT gain; htDVA score; DHI score; sinusoidal (whole-body; 0.1–2 Hz with 30°/s peak-velocity) vestibulo-ocular reflex (VOR) gain and phase; transient (whole-body, 150°/s2 acceleration to 50°/s constant velocity) VOR gain and time constant; optokinetic nystagmus (OKN) gain and time constant (whole-body, 50°/s constant velocity rotation). Our study showed that BPPV, and peripheral or central vestibular hypofunction were present in 34% of participants, suggesting a vestibular cause to their dizziness. Over half (57%) of these with a likely vestibular cause had BPPV, which is more than twice the percentage reported in other dizzy clinic studies. Our findings suggest that the physical DHI score and VOR time constant were best at detecting those with non-BPPV vestibular loss, but should always be used in conjunction with cHIT or vHIT, and that the htDVA score and vHIT gain were best at detecting differences between ipsilesional and contralesional sides.

scholarly journals Effects of whole-body vibrations on neuromuscular fatigue: a study with sets of different durations

PeerJ ◽  
2020 ◽  
Vol 8 ◽  
pp. e10388
Author(s):  
Miloš Kalc ◽  
Ramona Ritzmann ◽  
Vojko Strojnik
Keyword(s):  
High Frequency ◽  
Maximum Voluntary Contraction ◽  
Peak Torque ◽  
Voluntary Contraction ◽  
Neuromuscular Fatigue ◽  
Voluntary Activation ◽  
Whole Body ◽  
Peripheral Fatigue ◽  
Single Twitch ◽  
Whole Body Vibrations

Background Whole body vibrations have been used as an exercise modality or as a tool to study neuromuscular integration. There is increasing evidence that longer WBV exposures (up to 10 minutes) induce an acute impairment in neuromuscular function. However, the magnitude and origin of WBV induced fatigue is poorly understood. Purpose The study aimed to investigate the magnitude and origin of neuromuscular fatigue induced by half-squat long-exposure whole-body vibration intervention (WBV) with sets of different duration and compare it to non-vibration (SHAM) conditions. Methods Ten young, recreationally trained adults participated in six fatiguing trials, each consisting of maintaining a squatting position for several sets of the duration of 30, 60 or 180 seconds. The static squatting was superimposed with vibrations (WBV30, WBV60, WBV180) or without vibrations (SHAM30, SHAM60, SHAM180) for a total exercise exposure of 9-minutes in each trial. Maximum voluntary contraction (MVC), level of voluntary activation (%VA), low- (T20) and high-frequency (T100) doublets, low-to-high-frequency fatigue ratio (T20/100) and single twitch peak torque (TWPT) were assessed before, immediately after, then 15 and 30 minutes after each fatiguing protocol. Result Inferential statistics using RM ANOVA and post hoc tests revealed statistically significant declines from baseline values in MVC, T20, T100, T20/100 and TWPT in all trials, but not in %VA. No significant differences were found between WBV and SHAM conditions. Conclusion Our findings suggest that the origin of fatigue induced by WBV is not significantly different compared to control conditions without vibrations. The lack of significant differences in %VA and the significant decline in other assessed parameters suggest that fatiguing protocols used in this study induced peripheral fatigue of a similar magnitude in all trials.

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