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1. The Massive and Distant Clusters of WISE Survey. IV. The Distribution of Active Galactic Nuclei in Galaxy Clusters at z ∼ 1

   https://doi.org/10.3847/1538-4357/aaef83  

   Mo, Wenli; Gonzalez, Anthony; Stern, Daniel; Brodwin, Mark; Decker, Bandon; Eisenhardt, Peter; Moravec, Emily; Stanford, S. A.; Wylezalek, Dominika (December 2018, 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. Photoabsorbance of supported metal clusters: ab initio density matrix and model studies of large Ag clusters on Si surfaces

   https://doi.org/10.1039/D2CP04922H  

   Vazhappilly, Tijo; Kilin, Dmitri S.; Micha, David A. (May 2023, Physical Chemistry Chemical Physics)

   Metal clusters with 10 to 100 atoms supported by a solid surface show electronic structure typical of molecules and require ab initio treatments starting from their atomic structure, and they also can display collective electronic phenomena similar to plasmons in metal solids. We have employed ab initio electronic structure results from two different density functionals (PBE and the hybrid HSE06) and a reduced density matrix treatment of the dissipative photodynamics to calculate light absorbance by the large Ag clusters Ag N , N = 33, 37(open shell) and N = 32, 34 (closed shell), adsorbed at the Si(111) surface of a slab, and forming nanostructured surfaces. Results on light absorption are quite different for the two functionals, and are presented here for light absorbances using orbitals and energies from the hybrid functional giving correct energy band gaps. Absorption of Ag clusters on Si increases light absorbance versus photon energy by large percentages, with peak increases found in regions of photon energies corresponding to localized plasmons. The present metal clusters are large enough to allow for modelling with continuum dielectric treatments of their medium. A mesoscopic Drude–Lorentz model is presented in a version suitable for the present structures, and provides an interpretation of our results. The calculated range of plasmon energies overlaps with the range of solar photon energies, making the present structures and properties relevant to applications to solar photoabsorption and photocatalysis. 

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5. 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)