Vanadium dioxide has attracted much interest due to the drastic change of the electrical and optical properties it exhibits during the transition from the semiconductor state to the metallic state, which takes place at a critical temperature of about 68 °C. Much study has been especially devoted to developing advanced fabrication methodologies to improve the performance of VO thin films for phase-change applications in optical devices. Films structural and morphological characterisation is normally performed with expensive and time consuming equipment, as x-ray diffractometers, electron microscopes and atomic force microscopes.
View Article and Find Full Text PDFPurpose: The practice of removing "following" responses from speech perturbation analyses is increasingly common, despite no clear evidence as to whether these responses represent a unique response type. This study aimed to determine if the distribution of responses to auditory perturbation paradigms represents a bimodal distribution, consisting of two distinct response types, or a unimodal distribution.
Method: This mega-analysis pooled data from 22 previous studies to examine the distribution and magnitude of responses to auditory perturbations across four tasks: adaptive pitch, adaptive formant, reflexive pitch, and reflexive formant.
Background: Reflexive pitch perturbation experiments are commonly used to investigate the neural mechanisms underlying vocal motor control. In these experiments, the fundamental frequency-the acoustic correlate of pitch-of a speech signal is shifted unexpectedly and played back to the speaker via headphones in near real-time. In response to the shift, speakers increase or decrease their fundamental frequency in the direction opposing the shift so that their perceived pitch is closer to what they intended.
View Article and Find Full Text PDFSensorimotor adaptation experiments are commonly used to examine motor learning behavior and to uncover information about the underlying control mechanisms of many motor behaviors, including speech production. In the speech and voice domains, aspects of the acoustic signal are shifted/perturbed over time via auditory feedback manipulations. In response, speakers alter their production in the opposite direction of the shift so that their perceived production is closer to what they intended.
View Article and Find Full Text PDFAllerg Immunol (Paris)
January 1993
Antibody response to antigen A60 (a mycobacterial antigen) was evaluated in ELISA in 18 HIV+ subjects with clinical and cultural evidences of mycobacterial infections, in 10 HIV+ subjects without Mycobacterial infections and in 22 healthy donors. We found higher levels of specific IgG in the HIV+ patients with Mycobacterial infections (mean 179.2 +/- 83 U) compared to the values of the donors (mean 92.
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