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1. The Massive and Distant Clusters of WISE Survey. VII. The Environments and Properties of Radio Galaxies in Clusters at z ∼ 1

   https://doi.org/10.3847/1538-4357/ab5af0  

   Moravec, Emily; Gonzalez, Anthony H.; Stern, Daniel; Clarke, Tracy; Brodwin, Mark; Decker, Bandon; Eisenhardt, Peter R.; Mo, Wenli; Pope, Alexandra; Stanford, Spencer A.; et al (January 2020, The Astrophysical Journal)
2. The Massive and Distant Clusters of WISE Survey. V. Extended Radio Sources in Massive Galaxy Clusters at z ∼ 1

   https://doi.org/10.3847/1538-4357/aaf569  

   Moravec, Emily; Gonzalez, Anthony H.; Stern, Daniel; Brodwin, Mark; Clarke, Tracy; Decker, Bandon; Eisenhardt, Peter R.; Mo, Wenli; O’Donnell, Christine; Pope, Alexandra; et al (February 2019, The Astrophysical Journal)
3. Evolutionary dynamics of piRNA clusters in Drosophila

   https://doi.org/10.1111/mec.16311  

   Wierzbicki, Filip; Kofler, Robert; Signor, Sarah (December 2021, Molecular Ecology)

   Abstract Small RNAs produced from transposable element (TE)‐rich sections of the genome, termed piRNA clusters, are a crucial component in the genomic defence against selfish DNA. In animals, it is thought the invasion of a TE is stopped when a copy of the TE inserts into a piRNA cluster, triggering the production of cognate small RNAs that silence the TE. Despite this importance for TE control, little is known about the evolutionary dynamics of piRNA clusters, mostly because these repeat‐rich regions are difficult to assemble and compare. Here, we establish a framework for studying the evolution of piRNA clusters quantitatively. Previously introduced quality metrics and a newly developed software for multiple alignments of repeat annotations (Manna) allow us to estimate the level of polymorphism segregating in piRNA clusters and the divergence among homologous piRNA clusters. By studying 20 conserved piRNA clusters in multiple assemblies of fourDrosophilaspecies, we show that piRNA clusters are evolving rapidly. While 70%–80% of the clusters are conserved within species, the clusters share almost no similarity between species as closely related asD. melanogasterandD. simulans. Furthermore, abundant insertions and deletions are segregating within theDrosophilaspecies. We show that the evolution of clusters is mainly driven by large insertions of recently active TEs and smaller deletions mostly in older TEs. The effect of these forces is so rapid that homologous clusters often do not contain insertions from the same TE families. 

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4. Smallest water clusters supporting the ice I structure

   https://doi.org/10.1073/pnas.1918178116  

   Jordan, Kenneth D. (December 2019, Proceedings of the National Academy of Sciences)
5. Expansion kinematics of young clusters: I. Lambda Ori

   https://doi.org/10.1051/0004-6361/202451538  

   Armstrong, Joseph J; Tan, Jonathan C (December 2024, Astronomy & Astrophysics)

   Context.Most stars form in clusters or associations, but only a small number of these groups are expected to remain bound for longer than a few megayears. Once star formation has ended and the molecular gas around young stellar objects has been expelled via feedback processes, most initially bound young clusters lose the majority of their binding mass and begin to disperse into the Galactic field. Aims.This process can be investigated by analysing the structure and kinematic trends in nearby young clusters, particularly by analyzing the trend of expansion, which is a tell-tale sign that a cluster is no longer gravitationally bound and dispersing into the field. Methods.We combinedGaiaDR3 five-parameter astrometry with calibrated RVs for members of the nearby young clusterλOri (Collinder 69). Results.We characterised the plane-of-sky substructure of the cluster using theQ-parameter and the angular dispersion parameter. We find evidence that the cluster contains a significant substructure but that this is preferentially located away from the central cluster core, which is smooth and likely remains bound. We found strong evidence for expansion inλOri in the plane of sky by using a number of metrics, but we also found that the trends are asymmetric at the 5σsignificance level, with the maximum rate of expansion being directed nearly parallel to the Galactic plane. We subsequently inverted the maximum rate of expansion of 0.144_−0.003^+0.003kms⁻¹pc⁻¹to give an expansion timescale of 6.944_−0.142^+0.148Myr, which is slightly larger than the typical literature age estimates for the cluster. We also found asymmetry in the velocity dispersion as well as signatures of cluster rotation, and we calculated the kinematic ages for individual cluster members by tracing their motion back in time to their closest approach to the cluster centre. 

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