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Lip motion represents outsized importance in human communication, capturing nearly half of our visual attention during conversation. Yet anthropomorphic robots often fail to achieve lip-audio synchronization, resulting in clumsy and lifeless lip behaviors. Two fundamental barriers underlay this challenge. First, robotic lips typically lack the mechanical complexity required to reproduce nuanced human mouth movements; second, existing synchronization methods depend on manually predefined movements and rules, restricting adaptability and realism. Here, we present a humanoid robot face designed to overcome these limitations, featuring soft silicone lips actuated by a 10–degree-of-freedom mechanism. To achieve lip synchronization without predefined movements, we used a self-supervised learning pipeline based on a variational autoencoder (VAE) combined with a facial action transformer, enabling the robot to autonomously infer more realistic lip trajectories directly from speech audio. Our experimental results suggest that this method outperforms simple heuristics like amplitude-based baselines in achieving more visually coherent lip-audio synchronization. Furthermore, the learned synchronization successfully generalizes across multiple linguistic contexts, enabling robot speech articulation in 10 languages unseen during training. 

Supported noble metal catalysts, ubiquitous in chemical technology, often undergo dynamic transformations between reduced and oxidized states—which influence the metal nuclearities, oxidation states, and catalytic properties. 

Abstract. The Hunga Tonga–Hunga Ha′apai volcano erupted on 15 January 2022, launching Lamb waves and gravity waves into the atmosphere. In this study, we present results using 13 globally distributed meteor radars and identify the volcanogenic gravity waves in the mesospheric/lower thermospheric winds. Leveraging the High-Altitude Mechanistic general Circulation Model (HIAMCM), we compare the global propagation of these gravity waves. We observed an eastward-propagating gravity wave packet with an observed phase speed of 240 ± 5.7 m s−1 and a westward-propagating gravity wave with an observed phase speed of 166.5 ± 6.4 m s−1. We identified these waves in HIAMCM and obtained very good agreement of the observed phase speeds of 239.5 ± 4.3 and 162.2 ± 6.1 m s−1 for the eastward the westward waves, respectively. Considering that HIAMCM perturbations in the mesosphere/lower thermosphere were the result of the secondary waves generated by the dissipation of the primary gravity waves from the volcanic eruption, this affirms the importance of higher-order wave generation. Furthermore, based on meteor radar observations of the gravity wave propagation around the globe, we estimate the eruption time to be within 6 min of the nominal value of 15 January 2022 04:15 UTC, and we localized the volcanic eruption to be within 78 km relative to the World Geodetic System 84 coordinates of the volcano, confirming our estimates to be realistic.