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Szymko Y M YM Department of Bioengineering, University of Pennsylvania, Philadelphia 19104, - - 1995
1. The in vitro effect of intense stimulation on the micromechanical stiffness of hair cell sensory hair bundles was studied at three locations on the chick basilar papilla. Threshold levels of hair bundle motion, produced by a water jet stimulus, were examined before and after exposure to a 300 Hz ...
Zhang M - - 1995
After proper noise exposure, Hensen's cells, which have been shown to follow closely the response characteristics of the outer hair cells, suffered a loss of sensitivity at low and moderate SPLs. The lower the stimulus level, the greater was the loss. When the low-SPL loss did not exceed about 40 ...
Ryals B M - - 1995
Morphologic changes in the tegmentum vasculosum (TV) of adult quail after high intensity sound exposure were studied. Quail were continuously exposed to 115 dB SPL, 1500 Hz pure tone in a sound field for 12 h and either sacrificed immediately (0 day), 1, 2, 3, 4, 6 or 10 days ...
Saunders S S - - 1995
Three adult, female chickens, previously trained to detect pure tones using a positive reinforcement paradigm, were exposed to pure tones at 525 Hz at 120-dB sound-pressure level for 48 h. Immediately after exposure, pure-tone thresholds were elevated between 10 and 56 dB compared to pre-exposure values. The configuration of the ...
Yoshida M - - 1995
The cochlear microphonics (CM) in response to two-tone stimuli as well as the threshold of compound action potential (CAP) were measured before and after exposure to 4 kHz pure tone at 100 dB SPL for 10 min. Although the loss of CM output at the primary frequencies was limited to ...
Spadinger I - - 1995
Automated image cytometry techniques were used to measure motility and morphology in 3T3 fibroblasts exposed to extremely-low-frequency (ELF) magnetic fields. Cell motility and morphology were measured as a function of time before, during, and after 3-4 hour exposures to vertically oriented, 100 microTRMS sinusoidal magnetic fields at various frequencies in ...
Ylikoski M - - 1995
The peak sound pressure level (SPL), spreading of pressure wave and other physical characteristics of the impulse noise from weapons were studied in actual shooting conditions for assessment of gunfire noise exposure. Additionally, the attenuation of SPL by hearing protectors was measured with miniature microphones to evaluate protection efficiency in ...
Dalecki D - - 1995
The threshold for hemorrhage in mouse intestine was determined using the fields of a piezoelectric lithotripter. Exposures were controlled by variation of the position of the animal relative to the focus and by variation of the voltage used to charge the lithotripter. The range of peak positive pressure for exposures ...
Betancur C - - 1994
Exposure of adult male CD-1 mice to restraint stress for 60 min increased their hindpaw-licking latency in a hot-plate test (50 degrees C); this analgesia was significantly reduced after exposure to a stable magnetic field (MF) (30-40 G) under white light. In contrast, MF exposure under either red light or ...
Radwin R G - - 1994
A quantitative exposure assessment strategy for physical stress associated with repetitive manual tasks is proposed using continuous biomechanical data measured directly from electrogoniometers or force sensors. This paper describes an efficient method for reducing large quantities of biomechanical data into a quantifiable metric that accounts for recognized musculoskeletal exposure factors, ...
McGinn M D - - 1994
Spongiform lesions of the gerbil cochlear nucleus are reduced in number and extent by rearing in acoustic isolation compared with rearing while exposed to normal colony low-frequency background noise. This study tested whether rearing under exposure to noise bands of moderate intensity would increase the number and extent of cochlear ...
McLaren I P - - 1994
In two appetitive licking experiments, thirsty rats were pre-exposed on two stimuli prior to conditioning sessions in which one or both of these stimuli were paired with water. Consistent with other results, latent inhibition was disrupted when conditioning took place in a context different from that in which stimulus pre-exposure ...
Schneider T - - 1994
After pinealectomy, young pied flycatchers tested in the geomagnetic field have been found to be disoriented. In order to examine the possible role of the pineal hormone melatonin, handraised flycatchers were pinealectomized (PX) at the age of 8 weeks. From the day of operation onward, the PXMEL group received 100 ...
Lei S F - - 1994
Five computer-synthesized broadband noises, each having the same average spectrum and the same unweighted Leq of 100 dB SPL but very different temporal structures, were used to produce hearing loss in chinchillas. Despite the same exposure energies and spectra, each noise exposure produced a different magnitude and frequency distribution of ...
Cuzzani O E - - 1994
An increase in anterior chamber flare is associated with many ocular conditions, including retinal diseases. We assessed anterior chamber flare in 18 patients (19 eyes) with exudative age-related macular degeneration using the Kowa flare-cell meter immediately before and 1 hour after exposure to 40 light flashes at a flash intensity ...
Henselman L W - - 1994
Research has shown that prior noise exposures or 'conditioning' can moderate the amount of permanent threshold shift (PTS) from subsequent high intensity noise exposures. The aim of this experiment was to study the effect of 'conditioning' on subsequent exposure to high intensity impulse noise. The subjects were seven experimental and ...
Wang L - - 1994
Twenty-four guinea pigs with normal Preyer's reflex were exposed to the octave bands of noise centered at 63 Hz and 4 kHz, 110 dB SPL. The duration of exposure was 4 and 8 hours respectively. The permanent shift of the guinea pigs at the above two frequencies was at 4-8 ...
Syka J - - 1994
Middle latency responses (MLR) to acoustical stimulation (AS) and to electrical stimulation (ES) of the intact inner ear were recorded in guinea pigs. ES threshold curve decreased in the frequency range 2-16 kHz with a slope 5.4 dB/octave. Immediately after 50 mg/kg intravenous injection of the furosemide, which resulted in ...
Botte M C - - 1994
Three experiments studied the short-term effects of moderate- and high-level tone exposures on threshold and loudness. Experiment 1 measured temporary threshold and loudness shifts (TTS and TLS) due to a 1000-Hz exposure at a moderate level (65 dB SPL) as a function of exposure duration. Whereas there was no significant ...
O'Brien W D WD - - 1994
Two hundred and seventy mice were evaluated at three exposure durations (5, 10 and 20 min) and at six peak acoustic pressure levels (0, 65, 80, 87, 100 and 145 kPa) with 15 mice per exposure condition, at an ultrasonic frequency of 30 kHz modulated at 120 Hz. Threshold acoustic ...
Nishiyama K - - 1994
A new, self-recording, vibratory sensation meter measures temporary threshold shifts of vibratory sensation (TTSv) on a finger tip. After exposure to hand-transmitted vibration with exposure frequencies 63 Hz, 200 Hz and 500 Hz, and levels of acceleration 1 g, 2 g, 4 g and 8 g, fingertip measurements were obtained. ...
Hamernik R P - - 1994
Exposure of chinchillas to broadband, high-level impact noise on an interrupted 6-h daily schedule over 20 days has shown that pure-tone thresholds measured immediately following each daily exposure improve as much as 30 dB despite the continuing noise exposure. The time constant of this recovery effect (toughening) and the magnitude ...
Ryan A F - - 1994
Recent evidence suggests that prior exposure to a moderate-level acoustic stimulus can reduce damage due to later exposure to the same stimulus at high intensity [Canlon et al., Hear. Res. 34, 197-200 (1988)]. To test the role of the middle ear muscles (MEMs) in this phenomenon, Mongolian gerbils were conditioned ...
Yoshida M - - 1994
Guinea pigs were exposed to 2 kHz pure-tone or octave-band pass noise at an intensity of 100 dBSPL for 30 min. The effects of sound exposure on cochlear microphonics (CM) and compound action potential (AP) were studied using a test condition devised to complete the measurement of the sensitivity of ...
Boettcher F A - - 1993
The auditory brain-stem response (ABR) was recorded from young adult Mongolian gerbils exposed to noise (octave band of noise centered at 4 kHz, 80 dB SPL, 6 h on, 18 h off) for 12 days. Temporary threshold shift (TTS) of 20-50 dB was measured at 4-8 kHz and TTS of ...
Seidman M D - - 1993
Several studies have demonstrated that noise exposure may result in local vasoconstriction of cochlear vessels. The subsequent decrease in cochlear blood flow may lead to hypoxia and predispose to the formation of free oxygen radicals (FORs). If hypoxia occurs in response to noise exposure, then drugs that scavenge or block ...
Bolognesi C - - 1993
A large part of the commercial flower production in Italy is located in the located in the western part of the Liguria region, near the French border. The use of pesticides in this area has been much higher than the national average. The frequency of micronuclei in peripheral blood lymphocytes ...
Mensh B D - - 1993
An important issue in understanding the development of noise-induced hearing loss is whether prior acoustic overstimulation alters the susceptibility of the cochlea to further damage. The present work was designed to establish a model of activity-dependent changes in the susceptibility of the cochlea to acoustic overstimulation by regularly exposing the ...
Suits G W - - 1993
The noise generated by the otologic drill has been implicated as a cause of sensorineural hearing loss after ear surgery. However, clinical studies on this subject are contradictory and difficult to interpret. Therefore a guinea pig model was used to study whether the level of noise generated by the otologic ...
Harm D L - - 1993
Compensatory vertical eye movement gain (CVEMG) was recorded during pitch oscillation in darkness before, during and immediately after exposures to the stimulus rearrangement produced by the Preflight Adaptation Trainer (PAT) Tilt-Translation Device (TTD). The TTD is designed to elicit adaptive responses that are similar to those observed in microgravity-adapted astronauts. ...
Saunders J C - - 1993
One-day-old chicks were exposed to an intense pure tone (0.9 kHz, 120 dB SPL) and assigned to one of eight groups based on continuous exposure durations from 1 to 200 h. As each animal was removed from the exposure, it was anesthetized and an electrode was placed in the nucleus ...
Ahroon W A - - 1993
Auditory-evoked potential tuning curves were collected at six frequencies before and 30 days after various noise exposures in 363 chinchillas using a simultaneous masking paradigm. Traditional bivariate and multiple linear regression/correlation analyses were performed in an effort to determine the extent to which sensory cell damage could be estimated from ...
Miller D L - - 1993
Cavitation was produced by focused and unfocused ultrasonic beams in a 60-rpm rotating-tube exposure system. Hemolysis, free radical generation, and hydrogen peroxide were assayed after exposure to determine the dependence of cavitation activity on pressure-amplitude p and frequency f. For unfocused exposure, hemolysis rose rapidly from an apparent threshold pressure ...
Fox S E - - 1993
Repeated exposure to a stimulus increases one's affect toward that stimulus. This finding, termed the mere exposure effect, has been obtained even when the exposure durations are below the threshold of recognition. Reported are three experiments designed to assess whether the mere exposure effect for stimuli presented below the threshold ...
Koller M - - 1993
Light exposure was measured in six day and six night watches (working 12-hour shifts five days in a row) during 48 h on work days and 48 h on days off using a photocell with a sensitivity corresponding to photopic vision. The photocell was mounted on a frame of spectacles, ...
Hamernik R P - - 1993
An experiment was designed to determine if, for equal SPL and power spectrum, the effects on hearing of high-kurtosis noise exposures and a Gaussian noise exposure are different and the extent to which any differences measured in terms of audiometric and histological variables are frequency specific. Three groups of chinchillas ...
Lapota, D.
Phytoplankton bioassays have been used as biological tools in assessing environmental contamination. In our laboratory, a simple bioassay has been developed which measures the light output from bioluminescence dinoflagellates for assessment of toxic effects when exposed to a single toxicant or mixture. Successful use of this type of bioassay has ...
Botte M C - - 1993
Two experiments studied the frequency pattern of TLS (temporary loudness shift) as a function of the level and frequency of the fatiguing sound. In experiment 1, the fatiguing tones were intermittent 375-, 1500-, or 3000-Hz tones (10 s on/10 s off) at 75, 80, 85, 90, or 95 dB SPL. ...
Subramaniam M - - 1993
Recent research has revealed that repeated exposures to a low-frequency noise results in a progressive reduction in threshold shifts (TS). This reduction in TS is not restricted to the exposure frequency, but can be observed at frequencies up to 3 or 4 octaves higher. Such "conditioning" exposures have also been ...
Ishida A - - 1993
By examining 218 albino guinea pigs, electrophysiological methods were used to investigate the effects of low frequency ultrasound at moderate sound pressure levels after long-term exposure to the inner ear. From 10 kHz to 28 kHz, low frequency ultrasound below 100 dB SPL induced significant changes in cochlear microphonics, elevated ...
Kanno H - - 1993
In the present study we investigated the influence of decreased endocochlear potential (EP) on acoustic trauma. Guinea pigs with decreased EP following i.v. administration of furosemide (FUR) and normal EP given physiological saline solution (PSS) i.v. instead of FUR were exposed to 2 kHz pure tone ranging from 110 to ...
Coleman A J - - 1993
Extracorporeal shockwave lithotripsy (ESWL) has now been used for more than a decade in the treatment of urinary stone disease. During this period there has been a wide range of studies on the physical properties of the high-amplitude focussed fields used in ESWL and the biological effects of exposure to ...
Hall H - - 1993
In this study the detrimental impact of high level noise on temporary threshold shift (TTS) (i.e., hearing loss), was reduced when subjects were given suggestions of imaginary ear muffs attenuating the amplitude and aversive aspects of the noise. This effect was small, however, and only apparent when subjects' responses to ...
Lyskov E B - - 1993
The influence of sinusoidal 45-Hz magnetic fields on the brain functions of 20 volunteers was investigated in a double-blind study using spectral analysis of EEG and measurements of Omega potentials and reaction time (RT). The field strength was 1,000 A/m (1.26 mT) and the duration of exposure was 1 h. ...
Di Lollo V - - 1992
In partial-report experiments, an array of stimuli is displayed briefly, followed by a probe indicating the items to be reported. When exposure duration of the array is increased, 2 contrasting outcomes have been found: Some experiments find that performance improves (direct-duration effect); others find that it deteriorates (inverse-duration effect). The ...
Loving R T - - 1992
1. The light environment is a key element in the restoration and maintenance of health. 2. People need exposure to bright light (greater than 2,000 lux) to synchronize their circadian rhythms. 3. The affective state of people is related to their light exposure. 4. Bright light among psychiatric inpatients is ...
Drake-Lee A B - - 1992
Audiometry was undertaken before and within half an hour following a heavy metal concert to assess evidence of noise damage. Of the four members tested, one member wore an ear defender in his right ear during the period of noise exposure. All unprotected ears showed a temporary threshold shift which ...
Bornstein R F - - 1992
A meta-analysis of research on Zajonc's (1968) mere exposure effect indicated that stimuli perceived without awareness produce substantially larger exposure effects than do stimuli that are consciously perceived (Bornstein, 1989a). However, this finding has not been tested directly in the laboratory. Two experiments were conducted comparing the magnitude of the ...
Boettcher F A - - 1992
The compound action potential (AP) was recorded from one group of chinchillas exposed to interrupted noise (95 dB SPL, octave band centered at 500 Hz, 3 h on, 9 h off) for 15 days. A second group of chinchillas was exposed to the same interrupted noise for 1, 2 or ...
Bynoe L A - - 1992
Using the cytochrome c reduction method, we investigated light-dependent erythrocytic superoxide production. After 4 h light and dark exposure of erythrocytes from eight healthy human subjects, an average of 18.6% more superoxide was generated by erythrocytes exposed to light. Pretreatment of erythrocytes with the superoxide dismutase inhibitor N,N-diethyldithiocarbamate increased detection ...
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