250 research outputs found
HanstedgĂĽrd : A Settlement Site from the Funnel Beaker Culture
HanstedgĂĽrd - A Settlement Site from the Funnel Beaker Cultur
The role of temporal cues on voluntary stream segregation in cochlear implant users
Data from "The role of temporal cues in voluntary stream segregation for cochlear implant users"This work was supported by the Oticon Centre of Excellence for Hearing and Speech Sciences (CHeSS) and the Carlsberg foundation. The research equipment was provided by Cochlear Ltd
Objective assessment of stream segregation abilities of CI users as a function of electrode separation
Accuracy of averaged auditory brainstem response amplitude and latency estimates
<p><i>Objective</i>: The aims were to 1) establish which of the four algorithms for estimating residual noise level and signal-to-noise ratio (SNR) in auditory brainstem responses (ABRs) perform better in terms of post-average wave-V peak latency and amplitude errors and 2) determine whether SNR or noise floor is a better stop criterion where the outcome measure is peak latency or amplitude. <i>Design</i>: The performance of the algorithms was evaluated by numerical simulations using an ABR template combined with electroencephalographic (EEG) recordings obtained without sound stimulus. The suitability of a fixed SNR versus a fixed noise floor stop criterion was assessed when variations in the wave-V waveform shape reflecting inter-subject variation was introduced. <i>Study sample</i>: Over 100âhours of raw EEG noise was recorded from 17 adult subjects, under different conditions (e.g. sleep or movement). <i>Results</i>: ABR feature accuracy was similar for the four algorithms. However, it was shown that a fixed noise floor leads to higher ABR wave-V amplitude accuracy; conversely, a fixed SNR yields higher wave-V latency accuracy. <i>Conclusion</i>: Similar performance suggests the use of the less computationally complex algorithms. Different stop criteria are recommended if the ABR peak latency or the amplitude is the outcome measure of interest.</p
The Role of Place Cues in Voluntary Stream Segregation for Cochlear Implant Users
Sequential stream segregation by cochlear implant (CI) listeners was investigated using a temporal delay detection task composed of a sequence of regularly presented bursts of pulses on a single electrode (B) interleaved with an irregular sequence (A) presented on a different electrode. In half of the trials, a delay was added to the last burst of the regular B sequence, and the listeners were asked to detect this delay. As a jitter was added to the period between consecutive A bursts, time judgments between the A and B sequences provided an unreliable cue to perform the task. Thus, the segregation of the A and B sequences should improve performance. In Experiment 1, the electrode separation and the sequence duration were varied to clarify whether place cues help CI listeners to voluntarily segregate sounds and whether a two-stream percept needs time to build up. Results suggested that place cues can facilitate the segregation of sequential sounds if enough time is provided to build up a two-stream percept. In Experiment 2, the duration of the sequence was fixed, and only the electrode separation was varied to estimate the fission boundary. Most listeners were able to segregate the sounds for separations of three or more electrodes, and some listeners could segregate sounds coming from adjacent electrodes
Microsatellite markers for the biogeographically enigmatic sandmyrtle (Kalmia buxifolia, Phyllodoceae: Ericaceae)
Premise:
Microsatellite markers were developed for sandmyrtle, Kalmia buxifolia (Ericaceae), to facilitate phylogeographic studies in this taxon and possibly many of its close relatives.
Methods and Results:
Fortyâeight primer pairs designed from pairedâend Illumina MiSeq data were screened for robust amplification. Sixteen pairs were amplified again, but with fluorescently labeled primers to facilitate genotyping. Resulting chromatograms were evaluated for variability using three populations from Tennessee, North Carolina, and New Jersey, USA. Eleven primer pairs were reliable and polymorphic (mean 3.92 alleles), one was reliable but monomorphic, and four were not reliable. The markers exhibited lower heterozygosity (mean 0.246) than expected (mean 0.464). Crossâamplification in the remaining nine Kalmia species exhibited a phylogenetic pattern, suggesting broad applicability of the markers across the genus.
Conclusions:
These microsatellite markers will be useful in population genetics and species boundaries studies of K. buxifolia, K. procumbens, and likely all other Kalmia species.publishedVersio
Microsatellite markers for the biogeographically enigmatic sandmyrtle (Kalmia buxifolia, Phyllodoceae: Ericaceae)
Premise:
Microsatellite markers were developed for sandmyrtle, Kalmia buxifolia (Ericaceae), to facilitate phylogeographic studies in this taxon and possibly many of its close relatives.
Methods and Results:
Fortyâeight primer pairs designed from pairedâend Illumina MiSeq data were screened for robust amplification. Sixteen pairs were amplified again, but with fluorescently labeled primers to facilitate genotyping. Resulting chromatograms were evaluated for variability using three populations from Tennessee, North Carolina, and New Jersey, USA. Eleven primer pairs were reliable and polymorphic (mean 3.92 alleles), one was reliable but monomorphic, and four were not reliable. The markers exhibited lower heterozygosity (mean 0.246) than expected (mean 0.464). Crossâamplification in the remaining nine Kalmia species exhibited a phylogenetic pattern, suggesting broad applicability of the markers across the genus.
Conclusions:
These microsatellite markers will be useful in population genetics and species boundaries studies of K. buxifolia, K. procumbens, and likely all other Kalmia species.publishedVersio
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