Vibration perception

Rescue and safety workers have also been studied. Nishiwaki et al. (2001) studied 27 male rescue team staff and 30 police officers, 3-45 months after the event. The study subjects showed decreased performance on the digit span test however, no effects on stabilometry and vibration perception threshold were found. Li et al. (2004) followed 27 male firefighters and 25 male police officers three years after the attack for genotoxic effects. They found an elevated frequency of sister chromatid exchanges in lymphocytes of the victims which were related to the percentage of ChE inhibition observed just after the attack. 

Garrow AP, Boulton AIM. Vibration perception threshold- a valuable assessment of neural dysfunction in people with diabetes. Diabet Metab Res Rev 2006 22 411 41. 

Vibration Perception. The perception of vibration depends on the body site and on the stimulus firequency. The thresholds in Table 10.2 are typical of those for healthy adults, and are expressed as instantaneous RMS accelerations (i.e., with T 1 s in Eq. (10.2)). The value for whole-body vibration is given in terms of a frequency-weighted acceleration, and so is applicable to vibration at frequencies from 1 to 80 Hz. The values for hand-transmitted vibration are for sinusoidal stimuli applied to the fingertips of males (M) and females (F) at the specified frequencies. 

Chuang, H.Y., J. Schwartz, S.Y. Tsai, M.L. Lee, J.D. Wang, and H. Hu. 2000. Vibration perception thresholds in workers with long term exposure to lead. Occup. Environ. Med. 57(9) 588-594. 

Significant association (p < 0.05) between mean BLL and mean time-wei ted index of cumulative exposure and vibration perception in foot was foimd after adjustment for age, sex, height, smoking, alcohol consumption, use of vibrating hand tools. After adjustment for... 

Koyama, K., Yoshida, A., Takeda, A., Morozumi, K., and Fujinami, T., 1996. Efficacy of methylcobalamin in subclinical uremic neuropathy as detected by measuring vibration perception thresholds. Nephrology. 2 25-28. 

The battery of neuropsychological tests was designed to assess a range of functions implicated in previous studies of (a) chronic solvent abuse or occupational exposure to solvents, or (b) other CNS exposures, such as alcohol abuse in adults or severe head injury or meningitis in children and adolescents. It included measures of general intellectual and reading ability as well as tests to assess more specific functions such as psychomotor speed, attention, memory, manual and digital dexterity, and vibration perception. 

Vibration Perception Threshold Measurement Thumb and ankle... 

The Speed of Information Processing, Visual Perceptual Analysis Reac tion Time, Finger Tapping and Trail-Making tasks and the assessment of vibration perception thresholds were omitted. 

When the psychological test results were examined in relation to the number of different types of substances that the child had sniffed, a statistically significant effect on vibration sensation threshold measured at the ankle was found. The relationship appeared to be systematic, but in fact the direction of the effect was opposite to that predicted cases who had abused the most products showed the lowest thresholds of vibration perception relative to their controls. None of the other thirty- four measures showed a statistically significant effect. 

Various sources publish data of permissible vibration levels for employees (usually as a graph of acceleration against frequency). These are designed to avoid injury and cannot be used as a guide to the degree of disturbance caused by vibration. Vibration caused by neighboring industrial premises when received at a residence as vibration (i.e. no noise implications) has been considered a nuisance when it is just perceptible. 

Place die tester in a level position on a solid table free of vibration, in a location free of perceptible draft, and in a dim light. Maintain a room temp of 75—5 F (24t3 O thru-out the test... 

CH30N0(5i) for three selected resonance energies. The assignment in terms of vibrational quantum numbers to and n is described in the text. The dashed contours in the upper part represent the Si-state PES. The magnitudes of the wavefunctions in the exit channel are very much smaller than in the inner region of the potential. In order to make the tails of the wavefunctions perceptible the contours are chosen in a nonuniform way ... 

There are three widely accepted routes by which bone-conducted sound stimulates the cochlea. These are the compres-sional, inertial and osseotympanic theories of bone conduction (12). Compressional bone conduction implies that the cochlear shell is compressed slightly in response of the pressure variation caused by a sound. Inertial bone conduction alludes to a relative motion between the ossicular chain and the temporal bone for low frequency vibrations. The osseotympanic theory denotes a mechanism by which relative movement of the skull, with respect to the mandible, sets up pressure variation in the air present in the auditory meatus. Since perception of microwave pulses are correlated with the capacity to hear high-frequency sound, it rules out inertial or osseotympanic bone conduction as potential mechanisms for microwave acoustic effect. 

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