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1. Various Wavefront Sensing and Control Developments on the Santa Cruz Extreme AO Laboratory (SEAL) Testbed

   https://doi.org/10.1117/12.2630519  

   Gerrard, B.; Perez-Soto, J; Chambouleyron, V.; van Kooten, V.; Dillon, D.; Cetre, s.; Jensen-Clem, R.; Fu, Q.; Amata, H.; Heidrich, W. (August 2022, ArXivorg)
2. Contextualizing Late Holocene Subsistence Change on California’s Northern Channel Islands: A Middle Period Case Study from Santa Cruz Island

   https://doi.org/10.1080/1947461X.2024.2309833  

   Braje, Todd J; Gallanosa, Stephanie; Erlandson, Jon M; Gill, Kristina; Rick, Torben C (January 2024, California Archaeology)
3. Radiocarbon and stable isotope evidence of early to mid‐Holocene wet events from fluvial tufa deposits in Santa Cruz, CA

   https://doi.org/10.1002/jqs.3450  

   Kanner, Maura C.; Cortes, Luis; Ibarra, Yadira (November 2022, Journal of Quaternary Science)

   Abstract It is increasingly important to document past records of hydrologic change in areas that are drought‐prone to better predict the region's future vulnerability to recharge and water supply. Holocene spring‐associated carbonate deposits serve as terrestrial records of water balance that can complement other local, high‐resolution proxies that are moisture‐sensitive. Here we examine two carbonate deposits (one inactive perched tufa site and one active fluvial tufa site) that form from ambient‐temperature freshwater springs, as proxies of their depositional conditions. Radiocarbon (¹⁴C) analyses of charcoal fragments from the inactive perched tufa record depositional ages of 6.2 ± 0.06 (2σ) cal kabpand 8.0 ± 0.04 (2σ) cal kabpand agree with the age models from other proxies of past pluvial periods in the region (~16 to 5 ka). The active fluvial tufas date to 853 ± 0.4 calbp,representing conditions similar to modern flow. Geomorphologic and radiocarbon results indicate the perched tufa reflects wetter conditions fed by a higher water table. Stable isotopic analyses of carbonate (δ¹³C, δ¹⁸O) reveal distinct isotopic values between modern and early–mid‐Holocene tufa. This work underscores potential for the analysis of other moisture‐sensitive tufa deposits in coastal central California. 

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4. Reassessing floral diversity at Río Pichileufú, earliest middle Eocene of Río Negro, Argentina

   https://doi.org/10.26879/1383  

   Rossetto-Harris, Gabriella; Wilf, Peter (January 2024, Palaeontologia Electronica)

   The Río Pichileufú (RP) fossil locality contains one of Patagonia’s only well-dated middle Eocene floras, deposited ca. 47.7 Ma during the onset of global temperature decline and South America's tectonic isolation. In 1938, Edward W. Berry described 135 species from RP based on compressed angiosperm leaves and rare reproductive structures. The flora was considered highly diverse and to have predominantly Neotropical affinities; however, many of Berry’s identifications were botanically incorrect, confusing interpretations of composition, diversity, and biogeography. Only a fraction of the flora has been studied since, and substantial new collections have remained unevaluated. Here, we reassess the fossil leaves from RP, creating a stable platform for systematic and ecological analyses. We use a morphotype approach to bypass the numerous prior taxonomic errors, while preserving nomenclatural links to specimens. We jointly consider the type and cohort (n = 696) and recent (n = 1286) collections. We validate 82 leaf morphotypes in the type collections, much lower than Berry’s estimate of 131, and consider 43 species as indeterminate. We find that 44 historical species were improperly split, lumped, or misaligned to existing names. At least 12 plant families and 30 plant genera initially reported from the site are unreliable, including Poaceae, Cannabaceae, Ericaceae, Hydrangeaceae, and Rosaceae. However, considering all the collections, we recognize 158 total leaf morphotypes. Reliable taxa include ginkgophytes, Norfolk Island pines (Araucaria), legumes (Fabaceae), soapberries (Sapindaceae), and laurels (Lauraceae). Although Berry's initial assessment of diversity at RP was significantly overestimated, including new material re-establishes the flora as exceptionally diverse. 

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5. The ALMA Spectroscopic Survey in the HUDF: the Molecular Gas Content of Galaxies and Tensions with IllustrisTNG and the Santa Cruz SAM

   https://doi.org/10.3847/1538-4357/ab30f2  

   Popping, Gergö; Pillepich, Annalisa; Somerville, Rachel S.; Decarli, Roberto; Walter, Fabian; Aravena, Manuel; Carilli, Chris; Cox, Pierre; Nelson, Dylan; Riechers, Dominik; et al (September 2019, The Astrophysical Journal)