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  1. Following a recent phylogenetic study, we here review the circumscription of the grammitid fern genus Oreogrammitis (Polypodiaceae: Grammitidoideae). We propose three new genera Calligrammitis, Devolia, and Glabrigrammitis, to accommodate the three clades resolved outside of the core Oreogrammitis. The taxonomic treatment is presented, and the morphology of each new genus is shown with a color plate. 
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    Free, publicly-accessible full text available May 10, 2024
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  5. Adsorption of nanoparticles on a membrane can give rise to interactions between particles, mediated by membrane deformations, that play an important role in self-assembly and membrane remodeling. Previous theoretical and experimental research has focused on nanoparticles with fixed shapes, such as spherical, rod-like, and curved nanoparticles. Recently, hinge-like DNA origami nanostructures have been designed with tunable mechanical properties. Inspired by this, we investigate the equilibrium properties of hinge-like particles adsorbed on an elastic membrane using Monte Carlo and umbrella sampling simulations. The configurations of an isolated particle are influenced by competition between bending energies of the membrane and the particle, which can be controlled by changing adsorption strength and hinge stiffness. When two adsorbed particles interact, they effectively repel one another when the strength of adhesion to the membrane is weak. However, a strong adhesive interaction induces an effective attraction between the particles, which drives their aggregation. The configurations of the aggregate can be tuned by adjusting the hinge stiffness: tip-to-tip aggregation occurs for flexible hinges, whereas tip-to-middle aggregation also occurs for stiffer hinges. Our results highlight the potential for using the mechanical features of deformable nanoparticles to influence their self-assembly when the particles and membrane mutually influence one another. 
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  6. Abstract Grammitidoideae are the largest subfamily in Polypodiaceae and contain about 911 species. Progress has been made in understanding the overall phylogeny and generic boundaries in the light of recent molecular works. However, the majority of species, especially Asian species, and some critical type species of genera remain unsampled . In this study, a dataset of six plastid markers of 1003 (112 new) accessions representing ca. 412 species of Grammitidoideae including the type species of Ctenopterella , Grammitis , Moranopteris , Radiogrammitis , and Themelium , was assembled to infer a phylogeny. Our major results include: (1) the type species of Grammitis is successfully sequenced using a next‐generation sequencing technique and is resolved in Grammitis s.str. as expected; (2) Ctenopterella is found to be polyphyletic and a new clade consisting of C. khaoluangensis is resolved as sister to Tomophyllum ; (3) the type species of Ctenopterella is resolved in a clade sister to the C. lasiostipes clade; (4) Oreogrammitis is found to be polyphyletic and three clades outside of the core Oreogrammitis are identified containing O. subevenosa and allies, O. orientalis , and O. beddomeana (+ O. cf. beddomeana ); (5) Prosaptia is found to be paraphyletic with P. nutans being sister to a clade containing the rest of Prosaptia and Archigrammitis ; (6) the intergeneric and major relationships within the Asia‐Pacific clade are well resolved and strongly supported except for a few branches; (7) extensive cryptic speciation is detected in the Asia‐Pacific clade; and (8) based on the polyphyly of Ctenopterella we describe three new genera, Boonkerdia , Oxygrammitis , and Rouhania , for species formerly in Ctenopterella ; because the type species of Grammitis belongs to Grammitis s.str., we describe five new genera, Aenigmatogrammitis , Grammitastrum (stat. nov.), Howeogrammitis , Nanogrammitis , and Thalassogrammitis for species formerly in Grammitis s.l. A key to the 35 Old‐World genera is given, a taxonomic treatment is presented, and the morphology of all new genera is shown with either a color plate and/or a line drawing. 
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    Free, publicly-accessible full text available January 1, 2024
  7. The present topography of the northern Tibetan Plateau is characterized by the northwest-trending Eastern Kunlun Range, Qaidam Basin, and Qilian Shan, which figure importantly into the evolution and mechanism of Tibetan plateau development during Cenozoic Indo-Asian convergence. Understanding the Cenozoic deformation history and the source-to-sink relationship through time has significant implications for deciphering the growth history of the northern Tibetan Plateau. Despite decades of study, the timing, pattern, and mechanisms of deformation across the northern Tibetan Plateau are still vigorously debated. The North Qaidam thrust belt, located between the Qaidam Basin and Qilian Shan thrust belt, provides a valuable record of Cenozoic deformation in the northern Tibetan Plateau. Here, we present the results of new geologic mapping, structural and sedimentology analysis, and apatite fission track thermochronology to constrain the Cenozoic evolution history and reconstruct the paleogeomorphology of the eastern domain of the North Qaidam thrust belt and its foreland, the Wulan Basin. Our analyses reveal the North Qaidam thrust belt experienced multi-phase exhumation since the Cretaceous. A period of Eocene localized thrust-related uplift of the North Qaidam thrust belt initiated shortly after India-Asia collision, and lower erosion rates in the Oligocene allowed the thrust belt to expand along-strike eastward. Local uplift shed sediments to the southwest, directly into the Qaidam Basin. Reactivation of the proximal thrust faults and initiation of the northwest-striking right-slip Elashan fault at ca. 15−10 Ma drove the final accelerated mid-Miocene cooling and denudation to the surface. This phase of deformation established the overall framework morphology of the northeastern margin of the Tibetan Plateau, including the overall structure of the basins and ranges. 
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  8. Earthquake swarms are ubiquitous in volcanic systems, being manifestations of underlying nontectonic processes such as magma intrusions or volatile fluid transport. The Long Valley caldera, California, is one such setting where episodic earthquake swarms and persistent uplift suggest the presence of active magmatism. We quantify the long-term spatial and temporal characteristics of seismicity in the region using cluster analysis on a 25-year high-resolution earthquake catalog derived using leading-edge deep-learning algorithms. Our results show that earthquake swarms beneath the caldera exhibit enlarged families with statistically significant tendency for upward migration patterns. The ascending swarms tend to nucleate at the base of the seismogenic zone with a spatial footprint that is laterally constrained by the southern rim of the caldera. We suggest that these swarms are driven by the transport of volatile-rich fluids released from deep volcanic processes. The observations highlight the potential for extreme spatial segmentation of earthquake triggering processes in magmatic systems. 
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  9. null (Ed.)