Hydration in athletes

This issue of eMedRef provides information to clinicians on the pathophysiology, diagnosis, and therapeutics of hydration in athletes

Directions of seismic anisotropy in laboratory models of mantle plumes

A recent expansion in global seismic anisotropy data provides important new insights about the style of mantle convection. Interpretations of these geophysical measurements rely on complex relationships between mineral physics, seismology, and mantle dyn

A Human Torque Teno Virus Encodes a MicroRNA That Inhibits Interferon Signaling

Rodney P. Kincaid, James M. Burke, Jennifer C. Cox, Christopher S. Sullivan, The University of Texas at Austin, Molecular Genetics and Microbiology, Austin, Texas, United States of AmericaEthel-Michele de Villiers, Division for the Characterization of Tumorviruses, Deutsches Krebsforschungszentrum, Heidelberg, GermanyTorque teno viruses (TTVs) are a group of viruses with small, circular DNA genomes. Members of this family are thought to ubiquitously infect humans, although causal disease associations are currently lacking. At present, there is no understanding of how infection with this diverse group of viruses is so prevalent. Using a combined computational and synthetic approach, we predict and identify miRNA-coding regions in diverse human TTVs and provide evidence for TTV miRNA production in vivo. The TTV miRNAs are transcribed by RNA polymerase II, processed by Drosha and Dicer, and are active in RISC. A TTV mutant defective for miRNA production replicates as well as wild type virus genome; demonstrating that the TTV miRNA is dispensable for genome replication in a cell culture model. We demonstrate that a recombinant TTV genome is capable of expressing an exogenous miRNA, indicating the potential utility of TTV as a small RNA vector. Gene expression profiling of host cells identifies N-myc (and STAT) interactor (NMI) as a target of a TTV miRNA. NMI transcripts are directly regulated through a binding site in the 3′UTR. SiRNA knockdown of NMI contributes to a decreased response to interferon signaling. Consistent with this, we show that a TTV miRNA mediates a decreased response to IFN and increased cellular proliferation in the presence of IFN. Thus, we add Annelloviridae to the growing list of virus families that encode miRNAs, and suggest that miRNA-mediated immune evasion can contribute to the pervasiveness associated with some of these viruses.This work was supported by grants RO1AI077746 from the National Institutes of Health, RP110098 from the Cancer Prevention and Research Institute of Texas, a Burroughs Wellcome Investigators in Pathogenesis Award to CSS, a UT Austin Powers Graduate Fellowship to RPK, a UT Austin Institute for Cellular and Molecular Biology fellowship, and the DKFZ for EMdV. The funders had no role in study design, data collection and analysis, decision to publish, or preparation of the manuscript.Molecular BiosciencesMicrobiologyEmail: [email protected]

Melt segregation and depletion during ascent of buoyant diapirs in subduction zones

Author Posting. © American Geophysical Union, 2020. This article is posted here by permission of American Geophysical Union for personal use, not for redistribution. The definitive version was published in Journal of Geophysical Research-Solid Earth 125(2), (2020): e2019JB018203, doi:10.1029/2019JB018203.Cold, low‐density diapirs arising from hydrated mantle and/or subducted sediments on the top of subducting slabs have been invoked to transport key chemical signatures to the source region of arc magmas. However, to date there have been few quantitative models to constrain melting in such diapirs. Here we use a two‐phase Darcy‐Stokes‐energy model to investigate thermal evolution, melting, and depletion in a buoyant sediment diapir ascending through the mantle wedge. Using a simplified 2‐D circular geometry, we investigate diapir evolution in three scenarios with increasing complexity. In the first two scenarios we consider instantaneous heating of a diapir by thermal diffusion with and without the effect of the latent heat of melting. Then, these simplified calculations are compared to numerical simulations that include melting, melt segregation, and the influence of depletion on the sediment solidus along pressure‐temperature‐time (P ‐T ‐t ) paths appropriate for ascent through the mantle wedge. The high boundary temperature induces a rim of high porosity, into which new melts are focused and then migrate upward. The rim thus acts like an annulus melt channel, while the effect of depletion buffers additional melt production. Solid matrix flow combined with recrystallization of melt pooled near the top of the diapir can result in large gradients in depletion across the diapir. These large depletion gradients can either be preserved if the diapir leaks melt during ascent, or rehomogenized in a sealed diapir. Overall our numerical simulations predict less melt production than the simplified thermal diffusion calculations. Specifically, we show that diapirs whose ascent paths favor melting beneath the volcanic arc will undergo no more than ~40–50% total melting.We thank careful reviews by Juliane Dannberg, Harro Schmeling, and Bernhard steinberger. This work is supported by NSF‐1316333 (MB & NZ), NSF‐1551023 (MB), NSF‐1316310 (CK), and by China's Thousand Talents Plan (2015) and NSFC‐41674098 funding to NZ. The public data repository of Deal.ii (www.dealii.org) is thanked for distributing the software and examples that are used in this study. Computational work was conducted in High‐performance Computing Platform of Peking University, Kenny cluster of WHOI, and Pawsey Supercomputing Centre of Western Australia. We thank Timo Heister and Juliane Dannberg for deal.II technical assistance. The data of mantle wedge thermal structure and diapir trajectories, and the source code to compute the model results are available in the Mendeley data (http://dx.doi.org/10.17632/73n8zkc68s.1).2020-07-3

A Double-Thermostad Warm-Core Ring of the Gulf Stream

An unusual double-thermostad warm-core ring of the Gulf Stream was discovered in the Slope Sea, south of Georges Bank, during the R/V Endeavor cruise 578 in May 2016. The ring’s stratification was peculiar as it included two thermostads at, respectively, 100–200 m (core T = 18.14°C, S = 36.52) and 250–500 m (core T= 16.70°C, S = 36.35). Extensive use of satellite data (SST imagery and SSH maps) allowed the life history of this ring to be reconstructed, with independent SST and SSH data mutually corroborating each other. The double-thermostad ring was formed by vertical alignment of two preexisting warm-core anticyclonic rings of the Gulf Stream. The first ring spawned by the Gulf Stream in February has cooled by ~2°C before merging in April with the second ring spawned by the Gulf Stream in March. During vertical alignment of these rings, the warmer ring overrode the colder ring, thereby forming the double-thermostad ring surveyed in May 2016. From ADCP sections through the ring, the upper and lower thermostads had different core relative vorticities of −0.65f and −0.77f, respectively, where f is the local Coriolis parameter. An in-depth literature survey has confirmed that this is the first report of a double-thermostad warm-core ring of the Gulf Stream and one of the best-documented cases of vertical alignment of two eddies ever observed in the World Ocean

An Anomalous Near-Bottom Cross-Shelf Intrusion of Slope Water on the Southern New England Continental Shelf

Hydrographic surveys and moored observations in Rhode Island Sound (RIS) in water depths of 30–50 m, off the southern New England coast, revealed a near-bottom intrusion of anomalously warm and saline water in late fall 2009. The properties of this water mass, with peak salinity of nearly 35, are typical of slope water that is normally found offshore of the shelfbreak front, located approximately 100 km to the south. The slope water intrusion, with a horizontal spatial scale of about 45 km, appears to have been brought onto the outer shelf during the interaction of a Gulf Stream warm core ring with the shelfbreak east (upshelf) of RIS. The along-shelf transport rate of the intrusion can be explained as due to advection by the mean outer-shelf along-isobath current, although the transit time of the intrusion is also consistent with the self-advection of a dense bolus on a sloping shelf. The mechanism responsible for the large onshore movement of the intrusion from the outer shelf is not entirely clear, although a wind-driven upwelling circulation appeared to be responsible for its final movement into the RIS region. Depth-averaged salinity at all RIS mooring sites increased by 0.5–1 over the 3–4 week intrusion period suggesting that the intrusion mixed irreversibly, at least partially, with the ambient shelf water. The mixing of the salty intrusion over the shelf indicates that net cross-isobath fluxes of salt and other water properties have occurred

Oregon Bee Atlas: native bee findings from 2018

The Oregon Bee Atlas is a new volunteer-led effort to characterize the bee fauna of Oregon State by collecting, preparing, and databasing native bee species and capturing plant host records. In 2018, volunteers collected 11,044 bee specimens across 33 Oregon counties, representing 179 unique bee species, and 32 unique bee genera. Specimens were collected from a total of 310 unique flowering plant genera, resulting in one of the largest state-level databases of bee-host plant interactions. Volunteers produced valuable occurrence records for species poorly known for the State, and species of conservation concern. The 2018 efforts constitute a proof-of-concept of a specimen-focused volunteer native bee survey

The Modified Fisher Scale Lacks Interrater Reliability.

BACKGROUND: The modified Fisher scale (mFS) is a critical clinical and research tool for risk stratification of cerebral vasospasm. As such, the mFS is included as a common data element by the National Institute of Neurological Disorders and Stroke SAH Working Group. There are few studies assessing the interrater reliability of the mFS. METHODS: We distributed a survey to a convenience sample with snowball sampling of practicing neurointensivists and through the research survey portion of the Neurocritical Care Society Web site. The survey consisted of 15 scrollable CT scans of patients with SAH for mFS grading, two questions regarding the definitions of the scale criteria and demographics of the responding physician. Kendall\u27s coefficient of concordance was used to determine the interrater reliability of mFS grading. RESULTS: Forty-six participants (97.8% neurocritical care fellowship trained, 78% UCNS-certified in neurocritical care, median 5 years (IQR 3-6.3) in practice, treating median of 80 patients (IQR 50-100) with SAH annually from 32 institutions) completed the survey. By mFS criteria, 30% correctly identified that there is no clear measurement of thin versus thick blood, and 42% correctly identified that blood in any ventricle is scored as intraventricular blood. The overall interrater reliability by Kendall\u27s coefficient of concordance for the mFS was moderate (W = 0.586, p \u3c 0.0005). CONCLUSIONS: Agreement among raters in grading the mFS is only moderate. Online training tools could be developed to improve mFS reliability and standardize research in SAH

The Explanatory Value of Abstracting Away from Idiosyncratic and Messy Detail

Some explanations are relatively abstract: they abstract away from the idiosyncratic or messy details of the case in hand. The received wisdom in philosophy is that this is a virtue for any explanation to possess. I argue that the apparent consensus on this point is illusory. When philosophers make this claim, they differ on which of four alternative varieties of abstractness they have in mind. What's more, for each variety of abstractness there are several alternative reasons to think that the variety of abstractness in question is a virtue. I identify the most promising reasons, and dismiss some others. The paper concludes by relating this discussion to the idea that explanations in biology, psychology and social science cannot be replaced by relatively micro explanations without loss of understanding.This work has received funding from the European Research Council under the European Union’s Seventh Framework Programme (FP7/2007-2013)/ERC Grant agreement no 284123.This is the author accepted manuscript. The final version is available from Springer via http://dx.doi.org/10.1007/s11098-015-0554-