765 research outputs found
Psychoacoustical evaluation of the pitch-synchronous overlap-and-add speech-waveform manipulation technique using single-format stimuli
This article presents two experiments dealing with a psychoacoustical evaluation of the pitch synchronous overlap-and-add (PSOLA) technique. This technique has been developed for modification of duration and fundamental frequency of speech and is based on simple waveform manipulations. Both experiments were aimed at deriving the sensitivity of the auditory system to the basic distortions introduced by PSOLA. In experiment I, manipulation of fundamental frequency was applied to synthetic single-formant stimuli under minimal stimulus uncertainty, level roving, and formant-frequency roving. In experiment II, the influence of the positioning of the so-called "pitch markers" was studied. Depending on the formant and fundamental frequency, experimental data could be described reasonably well by either a spectral intensity-discrimination model or a temporal model based on detecting changes in modulation of the output of a single auditory filter. Generally, the results were in line with psychoacoustical theory on the auditory processing of resolved and unresolved harmonics
Vowel-onset detection by vowel-strength measurement, cochlear-nucleus simulation, and multilayer perceptrons
Downregulation of Fzd6 and Cthrc1 and upregulation of olfactory receptors and protocadherins by dietary beta-carotene in lungs of Bcmo1-/- mice.
An ongoing controversy exists on beneficial versus harmful effects of high beta-carotene (BC) intake, especially for the lung. To elucidate potential mechanisms, we studied effects of BC on lung gene expression. We used a beta-carotene 15,15'-monooxygenase 1 (Bcmo1) knockout mouse (Bcmo1-/-) model, unable to convert BC to retinoids, and wild-type mice (Bcmo1+/+) mice to dissect the effects of intact BC from effects of BC metabolites. As expected, BC supplementation resulted in a higher BC accumulation in lungs of Bcmo1-/- mice than in lungs of Bcmo1+/+ mice. Whole mouse genome transcriptome analysis on lung tissue revealed that more genes were regulated in Bcmo1-/- mice than Bcmo1+/+ mice upon BC supplementation. Frizzled homolog 6 (Fzd6) and collagen triple helix repeat containing 1 (Cthrc1) were significantly downregulated (fold changes -2.99 and -2.60, respectively, false discovery rate <0.05) by BC in Bcmo1-/-. Moreover, many olfactory receptors and many members of the protocadherin family were upregulated. Since both olfactory receptors and protocadherins have an important function in sensory nerves and Fzd6 and Cthrc1 are important in stem cell development, we hypothesize that BC might have an effect on the highly innervated pulmonary neuroendocrine cell (PNEC) cluster. PNECs are highly associated with sensory nerves and are important cells in the control of stem cells. A role for BC in the innervated PNEC cluster might be of particular importance in smoke-induced carcinogenesis since PNEC-derived lung cancer is highly associated with tobacco smoke
Downregulation of Fzd6 and Cthrc1 and upregulation of olfactory receptors and protocadherins by dietary beta-carotene in lungs of Bcmo1-/- mice.
An ongoing controversy exists on beneficial versus harmful effects of high beta-carotene (BC) intake, especially for the lung. To elucidate potential mechanisms, we studied effects of BC on lung gene expression. We used a beta-carotene 15,15'-monooxygenase 1 (Bcmo1) knockout mouse (Bcmo1-/-) model, unable to convert BC to retinoids, and wild-type mice (Bcmo1+/+) mice to dissect the effects of intact BC from effects of BC metabolites. As expected, BC supplementation resulted in a higher BC accumulation in lungs of Bcmo1-/- mice than in lungs of Bcmo1+/+ mice. Whole mouse genome transcriptome analysis on lung tissue revealed that more genes were regulated in Bcmo1-/- mice than Bcmo1+/+ mice upon BC supplementation. Frizzled homolog 6 (Fzd6) and collagen triple helix repeat containing 1 (Cthrc1) were significantly downregulated (fold changes -2.99 and -2.60, respectively, false discovery rate <0.05) by BC in Bcmo1-/-. Moreover, many olfactory receptors and many members of the protocadherin family were upregulated. Since both olfactory receptors and protocadherins have an important function in sensory nerves and Fzd6 and Cthrc1 are important in stem cell development, we hypothesize that BC might have an effect on the highly innervated pulmonary neuroendocrine cell (PNEC) cluster. PNECs are highly associated with sensory nerves and are important cells in the control of stem cells. A role for BC in the innervated PNEC cluster might be of particular importance in smoke-induced carcinogenesis since PNEC-derived lung cancer is highly associated with tobacco smoke
A rotating molecular ruler : determining nanometer-scale particle-particle distances in an optomagnetic cluster assay
We investigate a fast and sensitive optomagnetic biomarker detection technology based on magnetic particles. Antibody-coated superparamagnetic particles capture biomarker molecules and form clusters with a biomarker molecule sandwiched between two particles. The particle clusters are actuated using a rotating magnetic field, which induces an oscillating light scattering cross-section (see Fig. 1a). Sub-picomolar biomarker concentrations can be resolved by the light scattering signals [Ranzoni et al, Nanoletters 2011; ACS Nano 2012]. In this paper we report a method to quantify inter-particle distances with nanometer resolution. The light scattering data show high-frequency signal components (see Fig. 1b). Simulations show that high-frequency components hold detailed information about the geometry of the particle clusters, including a strong dependence on the inter-particle distance (see Fig. 1c). We will report the simulation results and experimental data of corresponding model cluster assays
Determination of the Strong Coupling \boldmath{\as} from hadronic Event Shapes and NNLO QCD predictions using JADE Data
Event Shape Data from annihilation into hadrons collected by the
JADE experiment at centre-of-mass energies between 14 GeV and 44 GeV are used
to determine the strong coupling . QCD predictions complete to
next-to-next-to-leading order (NNLO), alternatively combined with resummed
next-to-leading-log-approximation (NNLO+NLLA) calculations, are used. The
combined value from six different event shape observables at the six JADE
centre-of-mass energies using the NNLO calculations is
= 0.1210 +/- 0.0007(stat.) +/- 0.0021(expt.) +/- 0.0044(had.)
+/- 0.0036(theo.) and with the NNLO+NLLA calculations the combined value is
= 0.1172 +/- 0.0006(stat.) +/- 0.0020(expt.) +/- 0.0035(had.) +/-
0.0030(theo.) . The stability of the NNLO and NNLO+NLLA results with respect to
missing higher order contributions, studied by variations of the
renormalisation scale, is improved compared to previous results obtained with
NLO+NLLA or with NLO predictions only. The observed energy dependence of
agrees with the QCD prediction of asymptotic freedom and excludes
absence of running with 99% confidence level.Comment: 9 pages, EPHJA style, 4 figures, corresponds to published version
with JADE author lis
NNLO corrections to event shapes in annihilation
We compute the next-to-next-to-leading order (NNLO) QCD corrections to the
six most important event shape variables related to three-particle final states
in electron-positron annihilation. The corrections are sizeable for all
variables, however their magnitude is substantially different for different
observables. We observe that the NNLO corrections yield a considerably better
agreement between theory and experimental data both in shape and normalisation
of the event shape distributions. The renormalisation scale dependence of the
theoretical prediction is substantially reduced compared to the previously
existing NLO results. Our results will allow a precise determination of the
strong coupling constant from event shape data collected at LEP.Comment: 30 pages, LaTeX, numercial results corrected for oversubtraction of
large-angle soft radiatio
- β¦