Publications by authors named "Yilun Yu"

Article Synopsis
  • Exploring the role of valley manipulatable layered semiconductors, particularly in valleytronic devices, is the focus of this research on van der Waals (vdW) ReSe, highlighting its phonon chirality and scattering behavior.
  • The study employs various spectroscopic techniques to reveal critical features like the direction of Re chains, chiral phonon existence, and the influence of layer thickness and temperature on valley polarization strength.
  • The findings indicate potential advancements in valley physics and the development of valley(opto)tronic nanodevices using low-symmetry vdW ReSe due to its strong phonon-photon coupling and exciton-like effects.
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The polymorphic nature of InSe leads to excellent phase-dependent physical properties including ferroelectricity, photoelectricity, and especially the intriguing phase change ability, making the precise phase modulation of InSe of fundamental importance but very challenging. Here, the growth of InSe with desired-phase is realized by temperature-controlled selenization of van der Waals (vdW) layered bulk γ-InSe. Detailed results of Raman spectroscopy, scanning electron microscopy (SEM), and state-of-the-art spherical aberration-corrected transmission electron microscopy (Cs-TEM) clearly and consistently show that β-InSe, 3R α-InSe, and 2H α-InSe can be perfectly obtained at ≈270, ≈300, and ≈600 °C, respectively.

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  • Insects have developed various flight behaviors and traits that are crucial to understanding their evolutionary history, but studying extinct insects' flight capabilities is difficult.
  • An integrated approach reveals that the Palaeontinidae, a group of large cicadas from the Mesozoic era, underwent significant changes in anatomy and flight performance from the late Jurassic to early Cretaceous, showing increased speed and maneuverability.
  • This evolutionary adaptation may have been driven by competition with early birds, suggesting a competitive relationship known as an aerial evolutionary arms race, which illustrates how the evolution of powered flight has impacted animal evolution overall.
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  • Researchers have developed large-area 2D van der Waals (vdW) heterostructures using annealed SnSe, improving the yield and reproducibility over traditional mechanical methods that limit scalability.
  • The study employs in situ Raman analyses and advanced transmission electron microscopy to analyze the optimal conditions for forming SnSe layers, resulting in sharp interfaces and specific orientations.
  • Additionally, the optical properties of these heterostructures show unique valley polarization characteristics that allow adjustable band alignment, which could lead to innovative applications in photodetection and photovoltaics.
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  • Researchers describe a newly identified tiny ecdysozoan from the Cambrian period, characterized by its unique sack-like shape and spiny features.
  • This organism challenges the idea that early ecdysozoans always had a worm-like body plan, suggesting they may not have been elongated and tubular like many modern relatives.
  • The study positions this new species as a close relative to all known ecdysozoans, offering important insights into the evolutionary history and characteristics of early animal forms.
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  • Evidence of dinosaur reproduction before the Cretaceous is sparse, but new findings from the Lower Jurassic in southwestern China shed light on this topic.
  • The discovery includes three adult skeletons and five egg clutches of a new sauropodomorph, featuring unique reproductive traits like large, thick-shelled eggs and synchronized hatching.
  • These fossils indicate that the earliest dinosaur eggs were likely leathery and elliptical, marking a significant evolutionary shift in egg morphology occurring early in theropod evolution, rather than later with the birds.
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Major groups of jawed vertebrates exhibit contrasting conditions of dermal plates and scales. But the transition between these conditions remains unclear due to rare information on taxa occupying key phylogenetic positions. The 425-million-year-old fish Entelognathus combines an unusual mosaic of characters typically associated with jawed stem gnathostomes or crown gnathostomes.

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Pterosaurs, the earliest flying tetrapods, are the subject of some recent quantitative macroevolutionary analyses from different perspectives. Here, we use an integrative approach involving newly assembled phylogenetic and body size datasets, net diversification rates, morphological rates, and morphological disparity to gain a holistic understanding of the pterosaur macroevolution. The first two parameters are important in quantitative analyses of macroevolution, but they have been rarely used in previous pterosaur studies.

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Molecular studies suggest that the origin of jawed vertebrates was no later than the Late Ordovician period (around 450 million years ago (Ma)). Together with disarticulated micro-remains of putative chondrichthyans from the Ordovician and early Silurian period, these analyses suggest an evolutionary proliferation of jawed vertebrates before, and immediately after, the end-Ordovician mass extinction. However, until now, the earliest complete fossils of jawed fishes for which a detailed reconstruction of their morphology was possible came from late Silurian assemblages (about 425 Ma).

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Innovations relating to the consumption of hard prey are implicated in ecological shifts in marine ecosystems as early as the mid-Paleozoic. Lungfishes represent the first and longest-ranging lineage of durophagous vertebrates, but how and when the various feeding specializations of this group arose remain unclear. Two exceptionally preserved fossils of the Early Devonian lobe-finned fish Youngolepis reveal the origin of the specialized lungfish feeding mechanism.

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The end-Permian mass extinction (EPME) led to a severe terrestrial ecosystem collapse. However, the ecological response of insects-the most diverse group of organisms on Earth-to the EPME remains poorly understood. Here, we analyse beetle evolutionary history based on taxonomic diversity, morphological disparity, phylogeny, and ecological shifts from the Early Permian to Middle Triassic, using a comprehensive new dataset.

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Recent studies demonstrate that many avialan features evolved incrementally prior to the origin of the group, but the presence of some of these features, such as bird-like brooding behaviours, remains contentious in non-avialan dinosaurs. Here we report the first non-avialan dinosaur fossil known to preserve an adult skeleton atop an egg clutch that contains embryonic remains. The preserved positional relationship of the adult to the clutch, coupled with the advanced growth stages of the embryos and their high estimated incubation temperatures, provides strong support for the brooding hypothesis.

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Reconstructing the history of biodiversity has been hindered by often-separate analyses of stem and crown groups of the clades in question that are not easily understood within the same unified evolutionary framework. Here, we investigate the evolutionary history of birds by analyzing three supertrees that combine published phylogenies of both stem and crown birds. Our analyses reveal three distinct large-scale increases in the diversification rate across bird evolutionary history.

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Tetanurae is a special group of theropod dinosaurs that originated by the late Early Jurassic. It includes several early-diverging groups of generally large-bodied predators (megalosauroids, allosauroids, tyrannosauroid coelurosaurs) as well as morphologically disparate small-bodied coelurosaurs, including birds. Aspects of the evolutionary history of tetanurans remain contested, including the topology of their deep phylogenetic divergences (among Megalosauroidea, Allosauroidea and Coelurosauria).

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The bone-beds of the Upper Cretaceous Wangshi Group in Zhucheng, Shandong, China are rich in fossil remains of the gigantic hadrosaurid Shantungosaurus. Here we report a new oviraptorosaur, Anomalipes zhaoi gen. et sp.

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