A highly efficient, eco-friendly protocol has been developed for synthesis of spirooxindole-pyran derivatives via one-pot, three-component reaction of isatins, malononitrile, and enolizable C–H activated compounds (2-hydroxynaphthalene-1,4-dione, 4-hydroxycoumarine and dimedone) under visible-light irradiation in water-ethyl lactate at room temperature. The reported approach shows significant advantages such as a high yield, mild and clean reaction conditions, the application of clean visible light as a source of energy, the absence of catalyst, the use of ethyl lactate/water as an environmentally friendly solvent, a one-pot multicomponent reaction at room temperature, no chromatographic separation, and applicability for large-scale synthesis.

These findings indicate that some auditory dysfunctions may be present in patients with mild and moderate OSAS, and the damages were aggravated with the severity of OSAS, which suggests that speech-ABR may be a potential biomarker in the diagnosis and evaluation at early stage of OSAS.

The auditory steady-state response (ASSR) is one of the main approaches in clinic for health screening and frequency-specific hearing assessment. However, its generation mechanism is still of much controversy. In the present study, the linear superposition hypothesis for the generation of ASSRs was investigated by comparing the relationships between the classical 40 Hz ASSR and three synthetic ASSRs obtained from three different templates for transient auditory evoked potential (AEP). These three AEPs are the traditional AEP at 5 Hz and two 40 Hz AEPs derived from two deconvolution algorithms using stimulus sequences, i.e., continuous loop averaging deconvolution (CLAD) and multi-rate steady-state average deconvolution (MSAD). CLAD requires irregular inter-stimulus intervals (ISIs) in the sequence while MSAD uses the same ISIs but evenly-spaced stimulus sequences which mimics the classical 40 Hz ASSR. It has been reported that these reconstructed templates show similar patterns but significant difference in morphology and distinct frequency characteristics in synthetic ASSRs. The prediction accuracies of ASSR using these templates show significant differences (p < 0.05) in 45.95, 36.28, and 10.84% of total time points within four cycles of ASSR for the traditional, CLAD, and MSAD templates, respectively, as compared with the classical 40 Hz ASSR, and the ASSR synthesized from the MSAD transient AEP suggests the best similarity. And such a similarity is also demonstrated at individuals only in MSAD showing no statistically significant difference (Hotelling's T2 test, T2 = 6.96, F = 0.80, p = 0.592) as compared with the classical 40 Hz ASSR. The present results indicate that both stimulation rate and sequencing factor (ISI variation) affect transient AEP reconstructions from steady-state stimulation protocols. Furthermore, both auditory brainstem response (ABR) and middle latency response (MLR) are observed in contributing to the composition of ASSR but with variable weights in three templates. The significantly improved prediction accuracy of ASSR achieved by MSAD strongly supports the linear superposition mechanism of ASSR if an accurate template of transient AEPs can be reconstructed. The capacity in obtaining both ASSR and its underlying transient components accurately and simultaneously has the potential to contribute significantly to diagnosis of patients with neuropsychiatric disorders.

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This study reports the preliminary experiments, feature definitions and results for auditory brainstem responses (ABRs) evoked by a short speech syllable presented to healthy native-Chinese-speaking adults. Due to poor signal quality in the recording and the weakness nature of the brainstem response to particularly, the sophisticated sound, the resultant responses are selected based on criteria and rules in order to exclude the indistinct experiments runs. Feature waves/peaks are defined with modification of conventional fashion according to observed waveforms, which also induce the time domain analysis. Typical values of the components and the effects of stimulus intensity on the latency and amplitude are presented.