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Creators/Authors contains: "Wallman, James"

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  1. Abstract Fire-generated tornadic vortices (FGTVs) linked to deep pyroconvection, including pyrocumulonimbi (pyroCbs), are a potentially deadly, yet poorly understood, wildfire hazard. In this study we use radar and satellite observations to examine three FGTV cases during high-impact wildfires during the 2020 fire season in California. We establish that these FGTVs each exhibit tornado-strength anticyclonic rotation, with rotational velocity as strong as 30 m s −1 (60 kt), vortex depths of up to 4.9 km AGL, and pyroCb plume tops as high as 16 km MSL. These data suggest similarities to EF2+ strength tornadoes. Volumetric renderings of vortex and plume morphology reveal two types of vortices: embedded vortices anchored to the fire and residing within high-reflectivity convective columns and shedding vortices that detach from the fire and move downstream. Time-averaged radar data further show that each case exhibits fire-generated mesoscale flow perturbations characterized by flow splitting around the fire’s updraft and pronounced flow reversal in the updraft’s lee. All the FGTVs occur during deep pyroconvection, including pyroCb, suggesting an important role of both fire and cloud processes. The commonalities in plume and vortex morphology provide the basis for a conceptual model describing when, where, and why these FGTVs form. 
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  2. Abstract The Miltogramminae (Diptera: Sarcophagidae) includes ~600 species across >40 genera, which constitute ~20% of global Sarcophagidae. While molecular phylogenetic hypotheses have been produced for this group, critical problems persist, including the presence of paraphyletic genera, uncertain relationships between genera, a bias of sampling towards Palaearctic taxa, and low support for many branches. The present study remedies these issues through the application of Anchored Hybrid Enrichment (AHE) to a sample including ~60% of the currently recognised genera (16% of known species) representing all biogeographic regions except the Neotropical. An alignment of 1,281 concatenated loci was analysed with maximum likelihood (RAxML, IQ‐TREE), Bayesian inference (ExaBayes) and coalescent‐based approaches (ASTRAL, SVDquartets), which resulted in highly supported and concordant topologies, providing unprecedented insight into the relationships of this subfamily of flesh flies, allowing a major update to miltogrammine classification. The AHE phylogenetic hypothesis supports the monophyly of a large proportion of genera. The monophyly ofMetopiaMeigen is restored by synonymy withAenigmetopiaMalloch,syn.n.To achieve monophyly ofMiltogrammaMeigen, eight species are transferred fromPterellaRobineau‐Desvoidy. The genusPterellais shown to be paraphyletic in its current circumscription, and to restore generic monophylyPterellais restricted to contain onlyPt. grisea(Meigen).ErioproctaEnderlein,stat.rev., is resurrected. The genusSenotainiaMacquart is reconstructed as paraphyletic. The monotypic genusMetopodiaBrauer & Bergenstamm is synonymised withTaxigrammaMacquart,syn.n.In light of our phylogenetic hypotheses, a new Miltogramminae tribal classification is proposed, composed of six tribes. 
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