Search results for " Noise-Induced"
showing 10 items of 13 documents
IGF-1 Haploinsufficiency Causes Age-Related Chronic Cochlear Inflammation and Increases Noise-Induced Hearing Loss
2021
This article belongs to the Collection Insulin-Like Growth Factors in Development, Cancers and Aging.
Diltiazem for Prevention of Acoustical Trauma during Otologic Surgery
1995
100 patients were tested in a prospective, randomized, double-blinded study to assess the perioperative efficacy of a calcium channel blocker (diltiazem) in preventing acoustical trauma during otologic surgery. The patients were randomly divided into a therapy group (diltiazem) and a control group (placebo). Bone conduction hearing thresholds were examined preoperatively and again 1 day and 3 months postoperatively. Frequency-dependent changes in postoperative bone conduction and the number of patients with various degrees of postoperative hearing loss in both groups were statistically analyzed. The results indicated only a small postoperative hearing loss after ear surgery in both groups. …
Pattern formation and spatial correlation induced by the noise in two competing species
2004
We analyze the spatio-temporal patterns of two competing species in the presence of two white noise sources: an additive noise acting on the interaction parameter and a multiplicative noise which affects directly the dynamics of the species densities. We use a coupled map lattice (CML) with uniform initial conditions. We find a nonmonotonic behavior both of the pattern formation and the density correlation as a function of the multiplicative noise intensity.
Nonmonotonic behavior of spatiotemporal pattern formation in a noisy Lotka-Volterra system
2004
The noise-induced pattern formation in a population dynamical model of three interacting species in the coexistence regime is investigated. A coupled map lattice of Lotka-Volterra equations in the presence of multiplicative noise is used to analyze the spatiotemporal evolution. The spatial correlation of the species concentration as a function of time and of the noise intensity is investigated. A nonmonotonic behavior of the area of the patterns as a function of both noise intensity and evolution time is found.
Early Alterations of Endothelial Nitric Oxide Synthase Expression Patterns in the Guinea Pig Cochlea After Noise Exposure.
2019
Constitutively expressed endothelial nitric oxide synthase (eNOS) is supposed to play a role in noise-induced nitric oxide (NO)-production. It is commonly known that intense noise exposure results in inducible NOS (iNOS) expression and increased NO-production, but knowledge about a contribution of the eNOS isoform is still lacking. Effects of noise exposure on eNOS immunolabeling were determined in male guinea pigs ( n=24). For light microscopic analysis, 11 animals were exposed to 90 dB for 1 hr and 6 animals were used as controls. After exposure, eNOS immunostaining was performed on paraffin sections, and the staining intensities were quantified for 4 cochlear regions. For electron micro…
An experimental comparative study of dexamethasone, melatonin and tacrolimus in noise-induced hearing loss.
2008
The calcineurin inhibitor tacrolimus (TCR) and the pineal gland hormone and antioxidant melatonin (MLT) have been shown to possess otoprotective properties against noise-induced hearing loss (NIHL). In contrast, dexamethasone (DXM) was not effective as an otoprotective agent against NIHL. Further studies are needed to understand the exact molecular mechanisms involved.Exposure to noise pollution and use of audio devices for long periods of time at high volume is known to cause hearing loss or NIHL. Our goal was to evaluate the effectiveness of various known compounds such as the anti-inflammatory DXM, the antioxidant MLT and the immunosuppressant TCR against NIHL.Thirty-two Wistar rats were…
Endothelial nitric oxide synthase upregulation in the guinea pig organ of Corti after acute noise trauma.
2004
Endothelial nitric oxide synthase (eNOS) upregulation was identified 60 h after acute noise trauma in morphologically intact cells of the reticular lamina in the organ of Corti of the guinea pig in the second turn of the cochlea. Using gold-coupled anti-eNOS antibodies and electron microscopy, it was shown that eNOS expression was upregulated in all cell areas and cell types except inner hair cells. Furthermore, eNOS was found in the organelle-free cytoplasm and in mitochondria of various cell types. The density of eNOS in mitochondria was considerably higher compared with the surrounding cytoplasm. Since eNOS activity is regulated by calcium, the eNOS detection was combined with calcium pr…
Non-Gaussian noise effects in the dynamics of a short overdamped Josephson junction
2010
The role of thermal and non-Gaussian noise on the dynamics of driven short overdamped Josephson junctions is studied. The mean escape time of the junction is investigated considering Gaussian, Cauchy-Lorentz and Levy-Smirnov probability distributions of the noise signals. In these conditions we find resonant activation and the first evidence of noise enhanced stability in a metastable system in the presence of Levy noise. For Cauchy-Lorentz noise source, trapping phenomena and power law dependence on the noise intensity are observed.
Vitamin A deficiency increases noise susceptibility in guinea pigs.
1990
The effect of vitamin A deficiency in guinea pigs on noise-induced temporary threshold shift (TTS) was evaluated after short (15 min) acoustic overstimulation with a moderate (90 dB) broad-band white noise. Some guinea pigs were fed ad libitum a purified diet deficient in vitamin A (VAD group) until biochemical signs of deficiency occurred. A second, control group (VA group) received the same diet as well as 100 IU vitamin A daily by pharyngeal tube. Cochlear potentials were recorded by special computerized equipment using implanted electrodes. Before acoustic stimulation, a baseline value was determined with a test stimulus [90 dBA (A-filter according to usual DIN instructions)] correspond…
The Spike Noise Based on the Renewal Point Process and Its Possible Applications
2010
We consider a non-Markovian random process in the form of spikes train, where the time intervals between neighboring delta-pulses are mutually independent and identically distributed, i.e. represent the renewal process (1967). This noise can be interpreted as the derivative of well-known continuous time random walk (CTRW) model process with fixed value of jumps. The closed set of equations for the characteristic functional of the noise, useful to split the correlations between stochastic functionals (2008), is obtained. In the particular case of Poisson statistics these equations can be exactly solved and the expression for the characteristic functional coincides with the result for shot no…