Speech and music have structured rhythms, but these rhythms are rarely compared empirically. This study, based on large corpora, quantitatively characterizes and compares a major acoustic correlate of spoken and musical rhythms, the slow (0.25-32 Hz) temporal modulations in sound intensity. We show that the speech modulation spectrum is highly consistent cross 9 languages (including languages with typologically different rhythmic characteristics, such as English, French, and Mandarin Chinese). A different, but similarly consistent modulation spectrum is observed for Western classical music played by 6 different instruments. Western music, including classical music played by single instruments, symphonic, jazz, and rock music, contains more energy than speech in the low modulation frequency range below 4 Hz. The temporal modulations of speech and music show broad but well-separated peaks around 5 and 2 Hz, respectively. These differences in temporal modulations alone, without any spectral details, can discriminate speech and music with high accuracy. Speech and music therefore show distinct and reliable statistical regularities in their temporal modulations that likely facilitate their perceptual analysis and its neural foundations. Significance StatementSpeech and music are both rhythmic. This study quantifies and compares the acoustic rhythms of speech and music. A large corpus analysis is applied to speech across languages and to music across genres, including both classical music played by single instruments and ensemble music such as symphonic music, rock music and jazz. The analysis reveals consistent rhythmic properties within the category of speech and within the category of music, but clear distinctions between the two, highlighting potentially universal differences between these fundamental domains of auditory experience. IntroductionRhythmic structure is a fundamental feature of both speech and music. Both domains involve sequences of events (such as syllables, notes, or drum sounds) which have systematic patterns of timing, accent, and grouping (1). A primary acoustic correlate of perceived rhythm is the slow temporal modulation structure of sound, i.e. how sound intensity fluctuates over time (Fig. 1). For speech, temporal modulations below 16 Hz are related to the syllabic rhythm (2) and underpin speech intelligibility (3-5). For music, slow temporal modulations are related to the onsets and offsets of notes (or runs of notes in quick succession), which support perceptual phenomena such as beat, meter, and grouping (1,(6)(7)(8)(9)(10)(11)(12). Recently, a number of studies have investigated the neural activation patterns associated with the temporal modulations in the human brain and assessed their relevance to speech and music perception (13)(14)(15)(16)(17)(18)(19)(20).

When silicon oxide is stressed at high voltages, traps are generated inside the oxide and at the oxide's interfaces. The traps are negatively charged near the cathode and positively charged near the anode. The charge state of the traps can he easily changed by application of low voltages. Several models of trap generation have been proposed. These models involve either electron impact ionization processes or high field generation processes. We have attempted to determine the relative trap locations inside the oxides for oxides between 5 and 80 nm thick, in order to determine which processes are most likely. No evidence for a higher density of traps near the anode in any of these oxides was found, casting doubt on the efficiency of the impact ionization process in trap generation, even in thicker oxides. These data would support a trap generation model controlled by the high fields inside the oxides.

The tryptophan (Trp)-derived plant secondary metabolites, including camalexin, 4-hydroxy-indole-3-carbonylnitrile (4OH-ICN), and indole glucosinolate (IGS), show broad-spectrum antifungal activity. However, the upstream regulators of these metabolic pathways among different plant species in response to fungus infection are rarely studied. In this study, our results revealed a positive role of WRKY33 in host resistance to Alternaria brassicicola by directly regulating the transcription of genes involved in the biosynthesis and atypical hydrolysis of IGS both in Arabidopsis and Chinese kale. Indole-3-yl-methylglucosinolate (I3G) and 4-methoxyindole-3-yl-methylglucosinolate (4MI3G) are the main components of IGS. WRKY33 induces the expression of MYB51 and CYP83B1 which promotes the biosynthesis of I3G, the precursor of 4MI3G. Moreover, it also directly activates the expression of CYP81F2, IGMT1, and IGMT2 to drive side chain modification of I3G to produce 4MI3G, which is in turn hydrolyzed by PEN2. However, Chinese kale showed a more severe symptom than Arabidopsis when infected by Alternaria brassicicola. Comparative analyses of the origin and evolution of Trp-metabolism indicate that the loss of camalexin biosynthesis in Brassica crops during evolution might attenuate the resistance of crops to Alternaria brassicicola. As a result, IGS metabolic pathway mediated by WRKY33 becomes essential for Chinese kale to deter Alternaria brassicicola. Our results highlight the differential regulation of Trp-derived camalexin and IGS biosynthetic pathways in plant immunity between Arabidopsis and Brassica crops.One-sentence SummaryPathogen-responsive WRKY33 directly regulates indole glucosinolates biosynthesis and atypical hydrolysis, conferring to host resistance to Alternaria brassicicola in Arabidopsis and Brassica crops.