Visible lexical stress cues on the face do not influence audiovisual speech perception

Producing lexical stress leads to visible changes on the face, such as longer duration and greater size of the opening of the mouth. Research suggests that these visual cues alone can inform participants about which syllable carries stress (i.e., lip-reading silent videos). This study aims to determine the influence of visual articulatory cues on lexical stress perception in more naturalistic audiovisual settings. Participants were presented with seven disyllabic, Dutch minimal stress pairs (e.g., VOORnaam [first name] & voorNAAM [respectable]) in audio-only (phonetic lexical stress continua without video), video-only (lip-reading silent videos), and audiovisual trials (e.g., phonetic lexical stress continua with video of talker saying VOORnaam or voorNAAM). Categorization data from video-only trials revealed that participants could distinguish the minimal pairs above chance from seeing the silent videos alone. However, responses in the audiovisual condition did not differ from the audio-only condition. We thus conclude that visual lexical stress information on the face, while clearly perceivable, does not play a major role in audiovisual speech perception. This study demonstrates that clear unimodal effects do not always generalize to more naturalistic multimodal communication, advocating that speech prosody is best considered in multimodal settings

Photochemical alkene formation in sea water from dissolved organic carbon:results from laboratory experiments

The production mechanism of light alkenes, alkanes, and isoprene was investigated in laboratory experiments by measuring their concentrations in natural seawater as a function of spectral range, exposure time and origin, and concentration of dissolved organic carbon (DOC). The production mechanism of alkanes and of isoprene could not be clarified. Ethene and propene are produced photochemically from DOC. The relevant spectral range is UV and short‐wavelength visible light. Initial production rates (up to day 10 of exposure) were in the range of several pmol L−1 h−1 (mg DOC)−1; the corresponding mean quantum yields for the spectral range of 300–420 nm were about 10−8. Generally, the production rates and the quantum yields for ethene were about 2 times that of propene. The key factors in the total column integrated oceanic alkene production are the solar photon flux at sea surface, the penetration depth of the light into the ocean (especially the relation between different light absorbers, i.e., the extinction due to absorption of DOC), and the wavelength‐ and DOC‐dependent quantum yields. As a result of the high variability of these parameters, actual local alkene production rates for a specific oceanic region may differ considerably from the globally averaged oceanic alkene production rates. The latter were estimated to be at most 5 Mt yr−1

Percolation in the classical blockmodel

Classical blockmodel is known as the simplest among models of networks with community structure. The model can be also seen as an extremely simply example of interconnected networks. For this reason, it is surprising that the percolation transition in the classical blockmodel has not been examined so far, although the phenomenon has been studied in a variety of much more complicated models of interconnected and multiplex networks. In this paper we derive the self-consistent equation for the size the global percolation cluster in the classical blockmodel. We also find the condition for percolation threshold which characterizes the emergence of the giant component. We show that the discussed percolation phenomenon may cause unexpected problems in a simple optimization process of the multilevel network construction. Numerical simulations confirm the correctness of our theoretical derivations.Comment: 7 pages, 6 figure

Tropopause and hygropause variability over the equatorial Indian Ocean during February and March 1999.

Measurements of temperature, water vapor, total water, ozone, and cloud properties were made above the western equatorial Indian Ocean in February and March 1999. The cold-point tropopause was at a mean pressure-altitude of 17 km, equivalent to a potential temperature of 380 K, and had a mean temperature of 190 K. Total water mixing ratios at the hygropause varied between 1.4 and 4.1 ppmv. The mean saturation water vapor mixing ratio at the cold point was 3.0 ppmv. This does not accurately represent the mean of the measured total water mixing ratios because the air was unsaturated at the cold point for about 40% of the measurements. As well as unsaturation at the cold point, saturation was observed above the cold point on almost 30% of the profiles. In such profiles the air was saturated with respect to water ice but was free of clouds (i.e., backscatter ratio <2) at potential temperatures more than 5 K above the tropopause and hygropause. Individual profiles show a great deal of variability in the potential temperatures of the cold point and hygropause. We attribute this to short timescale and space-scale perturbations superimposed on the seasonal cycle. There is neither a clear and consistent “setting” of the tropopause and hygropause to the same altitude by dehydration processes nor a clear and consistent separation of tropopause and hygropause by the Brewer-Dobson circulation. Similarly, neither the tropopause nor the hygropause provides a location where conditions consistently approach those implied by a simple “tropopause freeze drying” or “stratospheric fountain” hypothesis

Do ichnotaxonomic differences between lacertoid tracks from the Tumlin Sandstone reflect producer biotaxonomic differences?

TheTumlin Sandstone is an eolian unit of disputable age (Late Permian or Early Triassic), exposed at the north-western border of the Holy Cross Mts., Central Poland. It contains abundant and diversified invertebrate and vertebrate trace fossils. The present paper considers ichno-biodiversity relation of lacertoid tracks and their producers occurring in the considered unit. A neoichnological experiment indicates that the recent lacertoid, Pogona vitticeps can produce morphologically diversified tracks which in fossil record would possibly be ascribed to different ichnogenera. The recorded variability range is qualitatively comparable to that of lacertoid tracks from the Tumlin Sandstone. It is thus possible that morphologically diversified lacertoid ichnogenera from the Tumlin Sandstone were produced by a single species. In consequence, morphologically diversified lacertoid ichnogenera from the Tumlin Sandstone might not be the equivalents of anatomically differentiated animals

Audiovisual Perception of Lexical Stress: Beat Gestures are stronger Visual Cues for Lexical Stress than visible Articulatory Cues on the Face

Human communication is inherently multimodal. Auditory speech but also visual cues can be used to understand another talker. This is especially known about the perception of segments of speech (i.e., speech sounds). However, less is known about the influence of visual information on the perception of suprasegmental aspects of speech like lexical stress. This study investigated the influence of different visual information (e.g., facial cues & beat gestures) on the perception of lexical stress and found that beat gestures, but not facial cues affect lexical stress perception. These results highlight the importance of considering suprasegmental aspects of language in multimodal contexts and expand our understanding of audiovisual speech perception and integration