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Despite being the largest estuary on the west coast of North America, no in-depth survey of microbial communities in San Francisco Bay (SFB) waters currently exists. In this study, we analyze bacterioplankton and archaeoplankton communities at several taxonomic levels and spatial extents (i.e., North versus South Bay) to reveal patterns in alpha and beta diversity. We assess communities using high-throughput sequencing of the 16S rRNA gene in 177 water column samples collected along a 150-km transect over a 2-year monthly time-series. In North Bay, the microbial community is strongly structured by spatial salinity changes while in South Bay seasonal variations dominate community dynamics. Along the steep salinity gradient in North Bay, we find that operational taxonomic units (OTUs; 97% identity) have higher site specificity than at coarser taxonomic levels and turnover ("species" replacement) is high, revealing a distinct brackish community (in oligo-, meso-, and polyhaline samples) from fresh and marine end-members. At coarser taxonomic levels (e.g., phylum, class), taxa are broadly distributed across salinity zones (i.e., present/abundant in a large number of samples) and brackish communities appear to be a mix of fresh and marine communities. We also observe variations in brackish communities between samples with similar salinities, likely related to differences in water residence times between North and South Bay. Throughout SFB, suspended particulate matter is positively correlated with richness and influences changes in beta diversity. Within several abundant groups, including the SAR11 clade (comprising up to 30% of reads in a sample), OTUs appear to be specialized to a specific salinity range. Some other organisms also showed pronounced seasonal abundance, including Synechococcus, Ca. Actinomarina, and Nitrosopumilus-like OTUs. Overall, this study represents the first in-depth spatiotemporal survey of SFB microbial communities and provides insight into how planktonic microorganisms have specialized to different niches along the salinity gradient.

Quasi-linear convective systems (QLCSs) are responsible for approximately a quarter of all tornado events in the United States, but no field campaigns have focused specifically on collecting data to understand QLCS tornadogenesis. The Propagation, Evolution, and Rotation in Linear Storms (PERiLS) project was the first observational study of tornadoes associated with QLCSs ever undertaken. Participants were drawn from more than 10 universities, laboratories, and institutes, with over 100 students participating in field activities. The PERiLS field phases spanned 2 years, late winters and early springs of 2022 and 2023, to increase the probability of intercepting significant tornadic QLCS events in a range of large-scale and local environments. The field phases of PERiLS collected data in nine tornadic and nontornadic QLCSs with unprecedented detail and diversity of measurements. The design and execution of the PERiLS field phase and preliminary data and ongoing analyses are shown. [ABSTRACT FROM AUTHOR]

ContextHospital-to-home transitions are critical opportunities to promote patient safety and high-quality care. However, such transitions are often fraught with difficulties associated with increased health care use and poor patient satisfaction.ObjectiveIn this review, we determine which pediatric hospital discharge interventions affect subsequent health care use or parental satisfaction compared with usual care.Data sourcesWe searched 7 bibliographic databases and 5 pediatric journals.Study selectionInclusion criteria were: (1) available in English, (2) focused on children

On 28 May 2019, a tornadic supercell, observed as part of Targeted Observation by UAS and Radars of Supercells (TORUS) produced an EF-2 tornado near Tipton, Kansas. The supercell was observed to interact with multiple preexisting airmass boundaries. These boundaries and attendant air masses were examined using unoccupied aircraft system (UAS), mobile mesonets, radiosondes, and dual-Doppler analyses derived from TORUS mobile radars. The cool-side air mass of one of these boundaries was found to have higher equivalent potential temperature and backed winds relative to the warm-side air mass; features associated with mesoscale air masses with high theta-e (MAHTEs). It is hypothesized that these characteristics may have facilitated tornadogenesis. The two additional boundaries were produced by a nearby supercell and appeared to weaken the tornadic supercell. This work represents the first time that UAS have been used to examine the impact of preexisting airmass boundaries on a supercell, and it provides insights into the influence environmental heterogeneities can have on the evolution of a supercell. [ABSTRACT FROM AUTHOR]

Recent studies have shown how very small differences in the background environment of a supercell can yield different outcomes, particularly in terms of tornado production. In this study, we use a novel convection initiation technique to simulate six supercells with a focus on their early development. Each experiment is identical, except for the strength of thermal forcing for the initial convection initiation. Each experiment yields a mature supercell, but differences in storm-scale characteristics like updraft speed, cold pool temperature deficit, and vertical vorticity development abound. Of these, the time when the midlevel updraft strengthens is most strongly related to initiation strength, with stronger thermal forcing favoring quicker updraft development. The same is true for the low-level updraft, with the additional relationship that stronger thermal forcing also tends to yield stronger low-level updrafts for around the first 2 h of the simulations. The experiments with faster updraft development tend to be associated with more rapid surface vortex intensification; however, cold pool evolution differs between simulations with weaker versus stronger thermal forcing. Stronger thermal forcing also yields deviant rightward storm motion earlier in the supercell's life cycle that remains more consistent for the duration of the simulation. These results highlight the range of supercellular outcomes that are possible across a background environment due to differences in storm-scale initiation strength. They are also of potential importance for predicting the paths and tornado potential of supercells in real time. Significance Statement: Despite a better understanding of processes related to tornado production in supercell thunderstorms, forecasters still have difficulty discriminating between tornadic and nontornadic supercells in close proximity to each other within the same severe weather event. In this study, we use six simulations of supercells to examine how these different outcomes can occur. Our results show that, given the same background environment, a storm that is more strongly initiated will exhibit faster updraft development and, possibly, quicker tornado production. The opposite can be said for storms that are more weakly initiated. Differences in initiation strength are also associated with different storm motions. These findings inspire future work to better relate supercell evolution to characteristics of initiation and the environment. [ABSTRACT FROM AUTHOR]

Abstract: A recent publication in Botany introduced two new taxa: a fossil orchid seed (Mycophoris) and a fossilized basidiomycete fungus (Synaptomitus) in an alleged relationship with this orchid, encased in [...]