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Stilp Christian E - - 2008
Early sensory processing is long thought to extract and exploit redundancy and regularity in the input, but perceptual evidence supporting this hypothesis has been limited. Experiments are reported demonstrating efficient encoding of multiple acoustic attributes resulting in the reduction of perceptual dimensionality. Stimuli varied across two complex independent dimensions: attackdecay ...
Lubis Syarif Husin - - 2008
A cross sectional study was conducted to investigate the effects of pesticide exposure (organophosphate and carbamate) using nerve conductive velocity, current perception threshold (CPT). Cluster random sampling was employed to recruit 64 paddy farmers and 22 fishermen in June 2006. The duration of pesticide exposure was between (5-20) years. The ...
Popelar Jiri - - 2008
Auditory brainstem responses (ABRs) and middle latency responses (MLRs) were compared after noise exposure to elucidate the specific effects of a loud sound on the central auditory system in rats. Rats were exposed twice for 1 h to broad-band noise (BBN) of 118 dB SPL (first exposure) and 122 dB ...
Peloi Lilian S - - 2008
The aim of this study was to propose the use of red light-emitting diode (LED) as an alternative light source for methylene blue (MB) photosensitizing effect in photodynamic therapy (PDT). Its effectiveness was tested against Staphylococcus aureus (ATCC 26923), Escherichia coli (ATCC 26922), Candida albicans (ATCC 90028) and Artemia salina. ...
Stocker Michael - - 2008
Anthropogenic noise is compromising habitat for marine mammals, fish and potentially other marine organisms. Determining acceptable exposure thresholds is confounded by the fact that marine animals have adapted to some exceedingly loud naturally occurring sounds, while exposure to certain anthropogenic noises at equivalent or lower amplitudes causes harm. It is ...
Finneran James J - - 2008
Increased public concern and regulation of activities involving anthropogenic sound have resulted in a pressing need for specific information regarding safe limits for marine mammals exposed to underwater noise. Since many marine mammals have sensitive hearing and rely upon underwater sound for communicating, foraging, and navigating, the potential effects of ...
Brink Mark - - 2008
The assessment of the impact of any kind of noise exposure on the population is a fundamental step in the process of noise abatement. Data about the exposure-response relationship for annoyance due to noise emissions from military shooting grounds are rather scarce at the time. In order to establish new ...
Krajcarz Fabien - - 2008
The level of daily exposure (Lex8h) of workers has to be measured in accordance with French standard NFS 31084. The attenuation of personal noise protection has to be determined according to standard NF EN ISO 4869-2. In addition to the difficulties of applying these methods, one has to be aware ...
Kastak David - - 2008
Investigation of auditory temporary threshold shift (TTS) in marine mammals has provided a means of predicting the harmful effects of underwater anthropogenic noise. As complete recovery of hearing is requisite in these studies, they have been considered appropriate in light of subject availability and ethical considerations. In our psychophysical studies ...
Arora Manish - - 2008
The occurrence of cavitation during HIFU exposure is associated with higher heating rates than in the absence of bubble activity. However, the peak rarefaction pressures required to initiate cavitation in vivo are high (7-10 MPa), making it difficult to localize, sustain, and confine cavitation activity and its associated bioeffects. In ...
Mooney T Aran - - 2008
For over a decade it has been suggested that high intensity anthropogenic sounds, such as sonar, could induce a temporary threshold shift (TTS) in odontocetes. Although TTS has been examined in marine mammals, the temporary physiological effects of sonar sounds have yet to be established. This study explored the effects ...
Boegli Hans - - 2008
The assessment of the impact of noise exposure on the population is a fundamental step in noise abatement. It includes the establishing of an exposure-response relationship and the setting of an impact threshold that specifies the protection level for the population and triggers eventually mitigating measures to reduce noise exposure. ...
Samson J - - 2008
Oxidative stress in the cochlea is considered to play an important role in noise-induced hearing loss. This study determined changes in superoxide dismutase (SOD), catalase, lipid peroxidation (LPO) and the auditory brainstem response (ABR) in the cochlea of C57BL/6 mice prior to and immediately, 1, 3, 7, 10, 14 and ...
Suvak Michael - - 2008
The authors conducted confirmatory factor analyses of reports of posttraumatic stress reactions using a national probability sample of individuals indirectly exposed to the terrorist attacks of September 11, 2001 (n = 675). Reactions at three time points in the year after the attacks were best accounted for by a lower-order, ...
Martínez-León Lluís - - 2008
We present a system for reconstructing single-exposure on-line (SEOL) digital holograms with improved resolution using a synthetic aperture. Several recordings are made in order to compose the synthetic aperture, shifting the camera within the hologram plane. After processing the synthetic hologram, an inverse Fresnel transformation provides an enhanced resolution reconstruction. ...
Pouyatos Benoît - - 2008
Potentiation of noise-induced hearing loss (NIHL) by specific chemical contaminants and therapeutic drugs represents a distinct public health risk. Prediction of chemicals that yield such potentiation has not been successful because such agents differ markedly in structure. One mechanism for this potentiation that has garnered support is oxidative injury to ...
Connolly Desmond M - - 2008
Thresholds to a temporally modulated contrast stimulus were examined across the central visual field, at photopic luminance (100 cd m(-2)), under aviation-related respiratory disturbances. These were mild hypoxia (14.1% oxygen), hyperoxia (100% oxygen), and hypocapnia (voluntary hyperventilation), with control exposures breathing air at rest. Thresholds were analysed by retinal eccentricity ...
Schäper Michael - - 2008
OBJECTIVES: The ototoxicity of occupational exposure to toluene plus noise was investigated in a longitudinal study in rotogravure printing and existing findings in the literature were evaluated. MATERIAL AND METHODS: The study comprised four repeated examinations during 5 years and started with 333 male workers. Lifetime weighted average exposures (LWAE) ...
Gerardi Gabriele - - 2008
A series of experiments on rats have been performed, to study the effects of long time (50 days) exposure to electromagnetic fields of extremely low frequency (ELF, i.e. less than 100 Hz) and amplitude (non thermal), testing whether the metabolic processes would be affected. The background lies on recent observations ...
Irlenbusch Lars - - 2007
The proximity of a mobile phone to the human eye raises the question as to whether radiofrequency (RF) electromagnetic fields (EMF) affect the visual system. A basic characteristic of the human eye is its light sensitivity, making the visual discrimination threshold (VDThr) a suitable parameter for the investigation of potential ...
Kastak David - - 2007
A California sea lion (Zalophus californianus) was tested in a behavioral procedure to assess noise-induced temporary threshold shift (TTS) in air. Octave band fatiguing noise was varied in both duration (1.5-50 min) and level (94-133 dB re 20 muPa) to generate a variety of equal sound exposure level conditions. Hearing ...
Jeon Junho - - 2008
The aim of the present study was to develop a biological early warning system (BEWS), equipped with six monitoring channels to individually observe the activity of Daphnia magna, using a digital 'Grid Counter', which would trigger an alarm within an appropriate time, and examine the functional performance of the newly ...
Chen Bo - - 2007
To support refinement of the ANSI Maximum Permissible Exposure safety limits, a series of experiments were conducted in vivo on Dutch Belted rabbit corneas to determine corneal minimum visible lesion thresholds for 2.0 microm continuous-wave laser irradiation. Single pulse radiant exposures were made at specified pulse durations of 0.1, 0.25, ...
Hamernik Roger P - - 2007
Sixteen groups of chinchillas (N=140) were exposed to various equivalent energy noise paradigms at 100 dB(A) or 103 dB(A) SPL. Eleven groups received an interrupted, intermittent, and time varying (IITV) non-Gaussian exposure quantified by the kurtosis statistic. The IITV exposures, which lasted for 8 hday, 5 daysweek for 3 weeks, ...
Straume Aksel - - 2007
The frequency spectra of electromagnetic fields have to be determined to evaluate human exposure in accordance to ICNIRP guidelines. In the literature, comparisons with magnetic field guidelines have been performed by using the frequency distribution of the current drawn from the battery. In the present study we compared the frequency ...
He Hai-Yan - - 2007
The shift in ocular dominance induced by brief monocular deprivation is greatest during a postnatal critical period and is thought to decline irreversibly thereafter. However, here we demonstrate that complete visual deprivation through dark exposure restores rapid ocular dominance plasticity in adult rats. In addition, the loss of visual acuity ...
Finneran James J - - 2007
Hearing sensitivity was measured in a bottlenose dolphin before and after exposure to an intense 20-kHz fatiguing tone in three different experiments. In each experiment, hearing was characterized using both the auditory steady-state response (ASSR) and behavioral methods. In experiments 1 and 2, ASSR stimuli consisted of seven frequency-modulated tones, ...
Popper Arthur N - - 2007
This study investigated the effects on rainbow trout (Oncorhynchus mykiss) of exposure to high-intensity, low-frequency sonar using an element of the standard Surveillance Towed Array Sensor System Low Frequency Active (LFA) sonar source array. Effects of the LFA sonar on hearing were tested using auditory brainstem responses. Effects were also ...
Petit-Demouliere Benoit - - 2007
Anxiolytic-like effect of diazepam is abolished by a previous exposure to four-plate test (FPT). Variations of temporal parameters: interval between trials and duration of Trial 1, with or without electric punishments allow characterizing factors which are responsible for this loss phenomenon. Complete spatial representation of FPT seems to be responsible ...
Lund David J - - 2007
The retinal injury threshold dose for laser exposure varies as a function of the irradiated area on the retina. Zuclich reported thresholds for laser-induced retinal injury from 532 nm, nanosecond-duration laser exposures that varied as the square of the diameter of the irradiated area on the retina. We report data ...
Kratochvíl B - - 2007
A comparison of the effects of ultrasound produced by low- and high-frequency ultrasonic apparatuses upon biological systems is one of the basic problems when studying ultrasound cavitation effects. One possibility for how to compare these effects is the indirect method which uses well-known physical quantities characterizing the interaction of ionizing ...
WoĊ‚kanowski Marek - - 2007
OBJECTIVES: Visual disturbances are commonly accepted criteria for acceleration tolerance assessment. Researchers during centrifuge experiments use them as a safe criterion for cessation of acceleration exposure. Visual disturbances analysis is a non-invasive method of assessing retinal blood flow. Limitation of visual stimuli perception is a measure of physiological state of ...
Falone Stefano - - 2007
The current study was designed to establish whether extremely low-frequency electromagnetic fields might affect neuronal homeostasis through redox-sensitive mechanisms. To this end, intracellular reactive oxygen species production, antioxidant and glutathione-based detoxifying capability and genomic integrity after extremely low-frequency electromagnetic fields exposure were investigated. Moreover, we also studied potential extremely low-frequency ...
Vercken Elodie - - 2007
Although multiple condition dependence in dispersal is common, the proximate mechanisms that integrate information from multiple sources remain largely unknown. In the common lizard (Lacerta vivipara), earlier studies have shown that maternal plasma corticosterone level interacts with maternal phenotype to affect offspring phenotype and dispersal strategy, and may reflect the ...
Lopresto V - - 2007
To investigate possible biological effects of exposure to electromagnetic (EM) fields at the frequencies of global system for mobile communication (GSM) 1800 system and universal mobile telecommunication system (UMTS) on the auditory system of rats, an exposure setup for in vivo experiments is presented. The study was carried out in ...
Brinker, Andrew
Ultraviolet light is typically associated with negative effects (e.g. cancer, sunburn etc.). However, recent studies have demonstrated the importance of ultraviolet light for calcium metabolism through production and regulation of vitamin D3. The present study surveyed the UVB exposure of three species of snakes at the Old Sabine Bottom Wildlife ...
Bapat U - - 2007
OBJECTIVE: To assess whether a temporary threshold shift occurred after recreational firearm use. DESIGN: An observational study of 25 subjects using ear protection in an indoor rifle range. Hearing was evaluated before and after shooting five rounds with a 0.22 calibre rifle over 10 minutes. A threshold shift of 5 ...
Gobba Fabriziomaria - - 2006
A suppression in melatonin secretion is one of the mechanisms proposed to explain the possible adverse effects of extremely low frequency magnetic fields (ELF-MF), but the results of research are inconclusive. This study investigated the effect of occupational ELF-MF exposure on 6-sulfatoximelatonin (6-OHMS). Exposure was monitored for three complete work ...
Bielefeld Eric C - - 2007
The influence of the sympathetic efferent fibers on cochlear susceptibility to noise-induced hearing loss is still an open question. In the current study, we explore the effects of unilateral and bilateral Superior Cervical Ganglion (SCG) ablation in the chinchilla on hearing loss from noise exposure, as measured with inferior colliculus ...
Carrasco María Magdalena - - 2006
The role of sensory experience in the development and plasticity of the visual system has been widely studied. It has generally been reported that once animals reach adulthood, experience-dependent visual plasticity is reduced. We have found that visual experience is not needed for the refinement of receptive fields (RFs) in ...
Kevanishvili Zurab - - 2006
The bounce phenomenon has been investigated in humans, evaluating alterations of click evoked otoacoustic emission (EOAE) after presentation of 250-Hz frequency loud tones during 3 min. EOAE changes were manifested in initial augmentation followed by reduction, peaking at 1 and 3 min of post-exposure time, respectively. Recoveries took 5-7 min ...
Sendowski I - - 2006
The therapeutic efficacy of cochlear infusion of methylprednisolone (MP) after an impulse noise trauma (170dB SPL peak) was evaluated in guinea pigs. The compound action potential threshold shifts were measured over a 14 days recovery period after the gunshot exposure. For each animal, one of the cochlea was perfused directly ...
Andresen, Norman A.
Cultures of Cyclotella meneghiniana and Melosira varians were split into four flasks. Two flasks of each taxon were used for exposure experiments and two were used as controls. Exposure to 1,3,5-trichlorobenzene was initiated in one flask of each taxon in the 1 lth hour of the light period on a ...
Sicko-Goad, Linda
Exposures of four diatoms, Cyclotella meneghiniana, Melosira italica, Melosira varians , and Synedra filiformis to 0.3 ppm 1,2,3-trichlorobenzene were initiated at the 8th and 11th hours of the light period on a 16:8 h L/D cycle at 20°C. Cell counts, lipid content, and lipid class composition were monitored for 10 ...
Ravera Silvia - - 2006
Exposure of fertilized eggs of the sea urchin Paracentrotus lividus to an electromagnetic field of 75-Hz frequency and low amplitudes (from 0.75 to 2.20 mT of magnetic component) leads to a dramatic loss of synchronization of the first cell cycle, with formation of anomalous embryos linked to irregular separation of ...
Hu Bo Hua - - 2006
This article has been retracted consistent with Elsevier Policy on Article Withdrawal. Please see The Publisher apologizes for any inconvenience this may cause.
Neitzel Richard L - - 2006
BACKGROUND: Commercial fishing workers have extended work shifts and potential for 24 hr exposures to high noise. However, exposures in this industry have not been adequately characterized. METHODS: Noise exposures aboard two catcher/processors (C/P) were assessed using dosimetry, sound-level mapping, and self-reported activities and hearing protection device (HPD) use. These ...
McLellan Tom M - - 2006
This report provides a summary of research conducted through a grant provided by the Workplace Safety Insurance Board of Ontario. The research was divided into two phases; first, to define safe work limits for firefighters wearing their protective clothing and working in warm environments; and, the second, to examine strategies ...
Ferrero Alejandro - - 2006
We analyze in detail the apparent violation of the reciprocity law that occurs for an interline CCD array owing to its responsivity that varies with exposure time, and we investigate other parameters having an influence on this variation, such as the numerical aperture of the system or the illumination wavelength. ...
Logvinov S V - - 2006
Light and electron microscopic methods were used to analyze changes in secretory neurons in the supraoptic (SON) and paraventricular (PVN) nuclei in the hypothalamus in 100 adult male rats at time points from the first minutes to 180 days after 48 hours of full-time exposure to bright light. At the ...
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