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ABSTRACT Sister taxa that have diverged and persisted in sympatry have likely been exposed to the same general environmental changes throughout their evolutionary history and may thus exhibit similar phylogeographies. Here, we compare the phylogeographic patterns of two sister species of isopods (genusTylos) that have broadly overlapping distributions but distinct habitat preferences in the supralittoral zone of Chile. The dynamic geoclimatic history of this region during the Quaternary has been implicated in shaping the evolutionary histories of other coastal taxa.Tylos spinulosusis found in sandy beaches at latitudes ~27°–30° S, whereasTylos chilensishas been found in rocky shores at ~27°–33° S and at ~39°–42° S. We sampled both species across their ranges (collectively from 20 localities) and obtained sequences from at least one mitochondrial gene for 95 T. chilensisand 41 T. spinulosus. We used phylogenetics and population genetics methods to analyze four single‐gene and one concatenated datasets: 12S rDNA (n = 130); 16S rDNA (n = 31); Cytochrome oxidase subunit I (n = 28); Cytochrome b (n = 24); concatenation of the four genes (n = 24). Both species show high levels of isolation of local populations, consistent with expectations from their limited autonomous dispersal potential. However, they exhibit strikingly different mitochondrial phylogeographic patterns.Tylos chilensisshows evidence of multiple relatively deep divergence events leading to geographically restricted lineages that appear to have persisted over multiple glaciations. Surprisingly, one lineage ofT. chilensiswas found in geographically distant localities, suggesting the possibility of human‐mediated dispersal.Tylos spinulosusappears to have undergone a relatively recent bottleneck followed by a population/range expansion. Differences in life histories and habitat preferences or stochasticity may have contributed to these striking phylogeographic differences. Finally, the high levels of differentiation and isolation among populations indicate that they are highly vulnerable to extirpation. We discuss threats to their persistence and recommendations for their conservation. 

N-Acyl-hydantoins have emerged as novel acyl transfer reagents for the synthesis of ketones via selective N–C(O) cleavage. Herein, we report two new protocols for the cross-coupling of N-acyl-5,5-dimethylhydantoins using versatile and readily accessible Pd–PEPPSI or Pd/phosphine catalysts. The acyl Suzuki reactions afford biaryl ketones in good to excellent yields under operationally-simple conditions using commercially-available, bench- and air-stable twisted N-acyl-hydantoins as acyl donors. The method complements and expands on the previous protocol for the cross-coupling of N-acyl-hydantoins (Org. Process Res. Dev. 2018, 22, 1188). 

Abstract Bottlebrush polymers (BB) have emerged as compelling candidates for biosystems to face tribological challenges, including friction and wear. This study provides a comprehensive assessment of an engineered triblock BB polymer's affinity, cell toxicity, lubrication, and wear protection in both in vitro and in vivo settings, focusing on applications for conditions like osteoarthritis and dry eye syndrome. Results show that the designed polymer rapidly adheres to various surfaces (e.g., cartilage, eye, and contact lens), forming a robust, biocompatible layer for surface lubrication and protection. The tribological performance and biocompatibility are further enhanced in the presence of hyaluronic acid (HA) both in vitro and in vivo. The exceptional lubrication performance and favorable interaction with HA position the synthesized triblock polymer as a promising candidate for innovative treatments addressing deficiencies in bio‐lubricant systems.