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Rapid, millennial-scale changes in sea level have been proposed for the beginning, middle, and/or end of the Last Interglacial (LIG) [~129 to 116 thousand years ago (ka)]. Each of these scenarios has different implications for polar ice sheet behavior in a warming world. Here, we present a suite of²³⁰Th ages for fossil corals in the Seychelles within a detailed sedimentary and stratigraphic context to evaluate the evolution of sea level during this past warm period. The rise to peak sea level at ~122 to 123 ka was punctuated by two abrupt stratigraphic discontinuities, defining three distinct generations of reef growth. We attribute the evidence of episodic reef growth and ephemeral sea-level fall to the competing influence of Northern Hemisphere ice melt and Antarctic ice regrowth. Asynchronous ice sheet contributions would mask the full extent of retreat for individual ice sheets during the LIG and imply greater temperature sensitivity of ice sheets than previously inferred. 

We explore the effects of sample size and shape on the percolation and electromechanical behaviors of liquid metal composites. 

Liquid metal fibers are increasingly used in soft multifunctional materials and soft electronics due to their superb stretchability, high conductivity, and lightweight. This work presents a systematic study of the electrospinning process of liquid metal microfibers. Compared to other methods that usually produce fibers thicker than 100 μm, electrospinning is a facile and low‐cost method of producing liquid metal fibers in the range of 10–100 μm. Specifically, core‐sheath liquid metal microfibers are fabricated with a highly conductive liquid metal core and a super‐stretchable thermoplastic elastomer sheath. This manufacturing process uses a liquid metal emulsion as the core solution, which circumvents manufacturing failures caused by the high surface tension of liquid metals. The influence of key processing parameters such as core flow rate, sheath flow rate, and applied voltage on the fiber diameter and morphology is studied by experiments. The mechanical and electrical properties of the as‐fabricated liquid metal microfibers, mats, and yarns are tested and discussed. 

Photonic technologies continue to drive the quest for new optical materials with unprecedented responses. A major frontier in this field is the exploration of nonlocal (spatially dispersive) materials, going beyond the local, wavevector-independent assumption traditionally adopted in optical material modeling. The growing interest in plasmonic, polaritonic, and quantum materials has revealed naturally occurring nonlocalities, emphasizing the need for more accurate models to predict and design their optical responses. This has major implications also for topological, nonreciprocal, and time-varying systems based on these material platforms. Beyond natural materials, artificially structured materials—metamaterials and metasurfaces—can provide even stronger and engineered nonlocal effects, emerging from long-range interactions or multipolar effects. This is a rapidly expanding area in the field of photonic metamaterials, with open frontiers yet to be explored. In metasurfaces, in particular, nonlocality engineering has emerged as a powerful tool for designing strongly wavevector-dependent responses, enabling enhanced wavefront control, spatial compression, multifunctional devices, and wave-based computing. Furthermore, nonlocality and related concepts play a critical role in defining the ultimate limits of what is possible in optics, photonics, and wave physics. This Roadmap aims to survey the most exciting developments in nonlocal photonic materials and metamaterials, highlight new opportunities and open challenges, and chart new pathways that will drive this emerging field forward—toward new scientific discoveries and technological advancements. 

Abstract Liquid metal composites are promising soft conductors for applications in soft electronics, sensors, and soft robotics. Existing liquid metal composites usually have a high‐volume fraction of liquid metal, which not only increases the density but also the material cost. Future applications in soft electronics and robotics highly demand liquid metal composites with low density and high conductivity for large‐scale, low‐cost, lightweight, and more sustainable applications. In this work, lightweight and highly conductive composites embedded with liquid metal fiber networks are synthesized. This new paradigm of liquid metal composites consists of an interconnected liquid metal fiber network embedded in a compliant rubber matrix. The liquid metal fiber network serves as an ultra‐lightweight conductive pathway for electrons. Experiments indicate that this soft conductive composite also possesses nearly strain‐insensitive conductance and superior cyclic stability. Potential applications of the composite films as stretchable interconnects, electrodes, and sensors are demonstrated.