Plates of aluminium (UNI 4507) of about 2.55 cm2 and 1.0 mm thick, of different shapes, vibrating in a liquid at a frequency of about 20 kHz and subjected to strong cavitation damage on their central parts exhibit, on the zone near the edge, a reduction of cavitative effect up ...

Lake Michigan mottled sculpin, Cottus bairdi, exhibit a naturally occurring and unconditioned orienting response that can be triggered by both live prey and chemically inert vibrating spheres, even in blinded animals. CoCl(2)-induced reductions of the orienting response demonstrate that the lateral line is required for this behavior in the absence ...

Developmental dyslexia is a disability of literacy skill that has also been associated with sensory processing deficits, primarily for the detection of dynamic auditory and visual stimuli. Here we examined whether analogous deficits extend into the domain of somatosensory perception. Detection thresholds for each of three frequencies of vibration were ...

This paper presents a method to measure the diaphragm tension of a condenser microphone where the fundamental frequency of the diaphragm is found from the input conductance of the microphone as a function of frequency. In this contact-free, purely electrical approach only the diaphragm and the backplate of the microphone ...

We review the mechanical origin of auditory-nerve excitation, focusing on comparisons of the magnitudes and phases of basilar-membrane (BM) vibrations and auditory-nerve fiber responses to tones at a basal site of the chinchilla cochlea with characteristic frequency approximately 9 kHz located 3.5 mm from the oval window. At this location, ...

Vibrations of the organ of Corti were measured in response to sound applied to the ear in the apical turn of a living guinea pig. Measurements were made at 29 points on the Reissner's membrane (RM) at 10 micro spacing along a radial track. Measurements also included 22 points on ...

Confocal microscopy was used to view the sealed apical turn of the cochlea in a living guinea pig, and to identify the cochlear structures through the intact Reissner's membrane. X, Y and Z coordinates for each point of interest were recorded. A confocal laser heterodyne interferometer measured the cellular vibration ...

The study presents the first attempt to investigate resonance properties of the living vocal folds by means of laryngoscopy. Laryngeal vibrations were excited via a shaker placed on the neck of a male subject and observed by means of videostroboscopy and videokymography (VKG). When the vocal folds were tuned to ...

This study reports a previously undescribed and unique sensillum. Some species of Lowrya Parker 1998 (Ostracoda: Cypridinidae) possess sensillae of an unusual type arranged in a single row parallel to, and near, the anterior, ventral and posterior margins of the external surface of each carapace valve. These sensilla are here ...

The track foundation is preloaded by multiple wheel loads due to the train weight and, as the pad and ballast are nonlinear, their stiffness depends upon the preload in them. Due to the influence of these resilient components of the track, the track vibration is affected by the wheel loads. ...

Mechanical static traction has been adopted as one of the treatment procedures for joint diseases and fractures. The effect of mechanical vibration on the mechanical traction of the temporomandibular joint was studied in six human subjects. A mechanical traction force of 2000 gf was applied as a dynamic traction force ...

The causes of low back pain associated with prolonged exposure to whole-body vibration are not understood. An understanding of non-linearities in the biomechanical responses is required to identify the mechanisms responsible for the dynamic characteristics of the body, to allow for the non-linearities when predicting the influence of seating dynamics, ...

The paper presents a novel method for recording amplitude and phase of 6D-vibrations of a spatial pendulum over a wide frequency range (10 Hz up to 20 kHz). The six degrees of freedom of the pendulum mass were monitored by three electrodynamic stereo pickups. At rest, the tips of the ...

It is not yet certain which sources of information are most important in judging the weight of a held object. In order to study this question further, a "deafferented" man and five controls flexed their wrist to lift a container weighing 1,000 g. Direct vision of the arm and weight ...

Juveniles of the Australian common imperial blue butterfly, Jalmenus evagoras, produce substrate-borne vibrational signals in the form of two kinds of pupal calls and three larval calls. Pupae stridulate in the presence of conspecific larvae, when attended by an ant guard, and as a reaction against perturbation. Using pupal pairs ...

The use of substrate vibrations in communication and predator-prey interactions is widespread in arthropods. In many contexts, localization of the vibration source plays an important role. For small species on solid substrates, time and amplitude differences between receptors in different legs may be extremely small, and the mechanisms of vibration ...

OBJECTIVES: To investigate the acute effects of the frequency of hand transmitted vibration on finger circulation. A further aim was to investigate whether the frequency weighting assumed in current standards for hand transmitted vibration reflects the haemodynamic changes which occur in the fingers exposed to vibration with different frequencies but ...

Reductions in vehicle vibration that may contribute to improvements in overall vehicle ride could individually be too small to be detected by drivers or passengers. This study investigated the 'difference threshold' (the difference in magnitude between two stimuli which is just sufficient for their difference to be detected) required for ...

Measurements from the 1-4-mm basal region of the chinchilla cochlea indicate the basilar membrane in the hook region (12-18 kHz) vibrates essentially as it does more apically, in the 5-9-kHz region. That is, a compressive nonlinearity in the region of the characteristic frequency, amplitude-dependent phase changes, and a gain relative ...

Earlier investigations have assumed only "out-of-plane" vibrations of the plates of the violin. The violin body can, however, be described as a thin-walled, double-arched shell structure and as such it may very well elongate in one direction as it contracts in another. Therefore, at least two orthogonal vibration components have ...

OBJECTIVE: The purpose of this study was to display the relationships between the forces transmitted in the spine and the accelerations of the vibrating seat. BACKGROUND: Investigations reveal that exposure to whole-body vibration can induce degenerative changes in the lumbar spine. Elevated spinal forces are probably the crucial component in ...

Waggle-dancing honeybees produce vibratory movements that may facilitate communication by indicating the location of the waggle dancer. However, an important component of these vibrations has never been previously detected in the comb. We developed a method of fine-scale behavioural analysis that allowed us to analyze separately comb vibrations near a ...

The vibration of the organ of Corti, a three-dimensional micromechanical structure that incorporates the sensory cells of the hearing organ, was measured in three mutually orthogonal directions. This was achieved by coupling the light of a laser Doppler vibrometer into the side arm of an epifluorescence microscope to measure velocity ...

The authors have found the acoustic levitation phenomenon where planar objects of 10 kg weight can be levitated near a vibration surface. This phenomenon has been studied for non-contact transportation. A circular planar object can be suspended without contacting a circular vibration plate. We have studied the holding force which ...

Density function theory calculations using B3' exchange functional and LYP' correlation functionals (B3LYP) with the 3-21G** basis set were carried out to study the molecular structure and fundamental vibrational frequencies of Si2H5Br, Si2H5I and their isotopomers. One scale factor used to scale Si-H(D) force constants for Si2H5Br is transferred from ...

Difference thresholds for seated subjects exposed to whole-body vertical sinusoidal vibration have been determined at two vibration magnitudes [0.1 and 0.5 ms(-2) root mean square (r.m.s.)] and at two frequencies (5 and 20 Hz). For 12 subjects, difference thresholds were determined using the up-and-down transformed response method based on two-interval ...

To investigate the response of gastric motility to whole-body vibration (WBV) exposure, electrogastrography (EGG) and gastric manometry were performed in 10 healthy male volunteers. Sinusoidal vertical vibration of three different frequencies (4 Hz, 8 Hz, and 16 Hz) with a constant vibration magnitude of 1.0 ms-2 (rms.) was randomly given ...

The paper describes a piezoelectric motor that combines the merits of piezoelectric materials, such as high power density generated at electromechanical resonance, and a precise control of displacement. In the motor, a standing shear wave is excited at the resonance in the piezoelectric tube, and it produces high-frequency torsional vibrations ...

A dry skull added with damping material was used to investigate the vibratory pattern of bone conducted sound. Three orthogonal vibration responses of the cochleae were measured, by means of miniature accelerometers, in the frequency range 0.1-10 kHz. The exciter was attached to the temporal, parietal, and frontal bones, one ...

Apparent masses of 15 male and 15 female subjects have been measured during exposure to various directions of horizontal vibration. Twenty vibration conditions were used in the experiment. In each of five directions (0, 22.5, 45, 67.5 and 90 degrees to the mid-sagittal plane) subjects were exposed to random vibration ...

Sensitivity of lateral motions relative to vertical motions were determined and compared to predictions provided by ISO 2631. Two experiments were executed where lateral and vertical motions were applied consecutively or simultaneously and where the magnitude of a single- or dual-axis test signal was adjusted until it was judged as ...

Parasitic wasps use a broad spectrum of different stimuli for host location and host acceptance. Here we review the published evidence for the use of mechanical stimuli, i.e. substrate born vibrations which are invariably regarded as vibrotaxis. We propose a set of criteria to class behavioural reactions as vibrotaxis or ...

Dampwood termites, Zootermopsis angusticollis, show an alarm response after detecting the presence of spores of the pathogenic fungus Metarhizium anisopliae. Termites in direct contact with a high concentration of spores (10(7) spores/ml) show a striking vibratory display which appears to convey information about the presence of pathogens to nearby unexposed ...

The recently developed technique of fibre optic respiratory plethysmography (FORP) has been modified to monitor the rapid, small amplitude movements of the chest wall during high-frequency oscillatory ventilation (HFOV). The FORP sensor is an expandable belt encircling the chest, in which is housed a fibre optic loop that alters its ...

This paper presents the results of laboratory experiment concerned with perception thresholds for whole-body vibration on recumbent subjects. Thresholds of subjects exposed to x-, y- and z-axis sinusoidal vibration were determined for supine, prone, lying on the left side and lying on the right side subjects (from 1 to 80 ...

Mechanical vibrations were measured at the apical turn in living guinea pig cochlea, in response to sinusoidal acoustic stimuli, using heterodyne interferometry. The cochlea was sealed and the vibrations were measured at different cellular locations along a radial track at the level of reticular lamina and one point on the ...

In this work, the tactual information transmission capabilities of a tactual display designed to provide stimulation along a continuum from kinesthetic movements to cutaneous vibrations are assessed. The display is capable of delivering arbitrary waveforms to three digits (thumb, index, and middle finger) within an amplitude range from absolute detection ...

PURPOSE: To investigate the feasibility of a confocal Raman spectroscopic technique for the noninvasive assessment of corneal hydration in vivo in two legally blind subjects. METHODS: A laser beam (632.8 nm; 15 mJ) was maintained on the cornea by using a microscope objective lens (x25 magnification, NA = 0.5, f ...

The present experiments addressed whether proprioception is used by the central nervous system (CNS) to control the spatial and temporal characteristics of unimanual circle drawing. Circle drawing is a multijoint movement, in which the muscles crossing the elbow and the shoulder are sequentially activated. The spatial and temporal characteristics of ...

Rotational transition frequencies of ArD+ were measured with an accuracy of a few hundred kilohertz in the 0.95-4.7 THz region, using a tunable far-infrared radiation source. Effective rotational parameters B, D, and H were determined for the ground vibrational state. The observed frequencies were combined with the previous data on ...

OBJECTIVES: The indoor environment of modern office buildings represents a new ecosystem that has been created totally by humans. Bacteria and fungi may contaminate this indoor environment, including the ventilation systems themselves, which in turn may result in adverse health effects. The objectives of this study were to test whether ...

The network behavior of cortical cells during the processing of a light flash was characterized in an isolated, but functionally intact, turtle visual system. Rapid changes in intracellular membrane potential were monitored optically using a voltage-sensitive dye (VSD). Spatially coherent changes in membrane potential were determined by subjecting high-speed movies ...

This study sought to analyze the postural responses induced by separately or simultaneously vibrating with different frequencies the forefoot and rear foot zones of both soles in standing subjects. Stimulating each zone separately resulted in spatially oriented body tilts; their amplitude and velocity varied linearly according to the frequency, and ...

BACKGROUND: The objectives of the study were to examine whether occupational use of vibrating hand-held tools was associated with an impaired vibrotactile perception, whether any exposure-response relationship exists, and whether the different populations of mechano-receptive afferent units are equally affected. METHODS: Vibrotactile perception thresholds have been measured at seven frequencies ...

Vibration of the seat and the body of a diesel locomotive and an electric locomotive were measured while driving on the railways of Eastern Finland. At the speed of 120 km/h for the diesel locomotive and 140 km/h for the electric locomotive (the greatest permissible speeds) the vibration of the ...

A tool or probe often functions as an extension of the hand, transmitting vibrations to the hand to produce a percept of the object contacting the tool or probe. This paper reports the psychophysical results of a combined psychophysical and neurophysiological study of the perception of vibration transmitted through a ...

The effect of transcutaneous vibration of the posterior neck muscles on the lateralization of dichotic sound was investigated in human subjects. Two-alternative forced-choice (left/right) judgements were made on acoustic stimuli presented with different interaural level differences via headphones during neck-muscle vibration. A shift of the subjective auditory median plane toward ...

Ultrasound-stimulated vibro-acoustic spectrography is a recently-developed method that employs the radiation force of two intersecting continuous ultrasound beams to remotely vibrate an object at an arbitrary low frequency. Object vibration produces a sound field (acoustic emission) in the medium, which is a function of object mechanical properties. By measuring the ...

A Wiener filter-based deconvolution algorithm is developed to restore vibration-degraded video imagery from an intensified CCD camera. The method is based on the use of azimuth and elevation angular optical line-of-sight data recorded from external sensors to estimate a two-dimensional vibration-blur impulse response on a per frame basis. Flight conditions ...

OBJECTIVE: This study was designed to determine whether stapes movement is pistonlike or complex. BACKGROUND: The literature provides conflicting information on whether stapes footplate motion is only pistonlike or has other types of movement, such as hingelike or rocking. METHODS: Using 10 freshly harvested human cadaver temporal bones, 3 targets ...