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Ground deformation and gravity changes in active calderas during periods of unrest can signal an impending eruption and thus must be correctly interpreted for hazard evaluation. It is critical to differentiate variation of geophysical observables related to volume and pressure changes induced by magma migration from shallow hydrothermal activity associated with hot fluids of magmatic origin rising from depth. In this paper we present a numerical model to evaluate the thermo-poroelastic response of the hydrothermal system in a caldera setting by simulating pore pressure and thermal expansion associated with deep injection of hot fluids (water and carbon dioxide). Hydrothermal fluid circulation is simulated using TOUGH2, a multicomponent multiphase simulator of fluid flows in porous media. Changes in pore pressure and temperature are then evaluated and fed into a thermo-poroelastic model (one-way coupling), which is based on a finite-difference numerical method designed for axi-symmetric problems in unbounded domains. Based on data for the Campi Flegrei caldera (Italy), a series of simulations assess the influence of fluid injection rates and mechanical properties on the hydrothermal system, uplift and gravity. Heterogeneities in hydrological and mechanical properties associated with the presence of ring faults are a key determinant of the fluid flow pattern and consequently the geophysical observables. Peaks (in absolute value) of uplift and gravity change profiles computed at the ground surface are located close to injection points (namely at the centre of the model and fault areas). Temporal evolution of the ground deformation indicates that the contribution of thermal effects to the total uplift is almost negligible with respect to the pore pressure contribution during the first years of the unrest, but increases in time and becomes dominant after a long period of the simulation. After a transient increase over the first years of unrest, gravity changes become negative and decrease monotonically towards a steady state value. Since the physics of the investigated hydrothermal system is similar to any fluid-filled reservoir, such as oil fields or CO2 reservoirs produced by sequestration, the generic formulation of the model will allow it to be employed in monitoring and interpretation of deformation and gravity data associated with other geophysical hazards that pose a risk to human activity. [ABSTRACT FROM AUTHOR]

This paper explores the relationship between vadose zone hydrology and geochemical changes in mixed mineralogy carbonate sands from a Bahamian coastal dune of Holocene age. Cores were taken from two sites: at site A, a shallow humic Entisol is developed beneath open scrub vegetation, while at site B a deeper, more organic-rich Inceptisol has formed beneath a mature hardwood coppice. X-ray diffraction analysis reveals significant contrasts in mineralogy both within and between the two sites, with partial stabilization of high-Mg calcite and aragonite, to low-Mg calcite. Stabilization is greater at site B, and is accompanied by a significant increase in total porosity. Diagenetic changes in poresize distribution have implications for residence times of percolating water, as determined using measurements of moisture retention characteristics using pressure plate apparatus, and hydrological models of unsaturated zone moisture flux. The diagenetically moremature sands from site B have a 50--100 per cent higher moisture retention, although unsaturated hydraulic conductivity is also higher, particularly at greater suctions. The increase in water retention is likely to enhance further rates of mineral-controlled reactions, whiledevelopment of an organic-rich soil also enhances the geochemical drive for dissolution. Carbonate diagenesis thus appears to be stronglylinked to vadose zone hydrology, and the interactions identified here have important consequences for the nature and long-term rates of mineral stabilization. [ABSTRACT FROM AUTHOR]

Biofilms are mucilaginous-organic layers produced by microbial activity including viruses. Growing biofilms form microbial mats which enhance sediment stability by binding particles with extracellular polymeric substances and promoting growth through nutrient cycling and organic matter accumulation. They preferentially develop at the sediment-water interface of both marine and non-marine environments, and upon the growing surfaces of modern tufa and travertine. In this context, however, little is known about the factors, environmental or anthropogenic, which affect viral communities in freshwater spring settings. To explore this issue, geochemical and metagenomic data were subjected to multidimensional analyses (Principal Component Analysis, Classical Multidimensional Scaling, Partial Least Squares analysis and cluster analysis based on beta-diversity), and these show that viral composition is specific and dependent on environment. Indeed, waters precipitating tufa and travertine do vary in their geochemistry with their viruses showing distinct variability between sites. These differences between virus groups allow the formulation of a viral proxy, based on the Caudoviricetes/Megaviricetes ratio established on the most abundant groups of viruses. This ratio may be potentially used in analysing ancient DNA preserved in carbonate formations as an additional source of information on the microbiological community during sedimentation., (© 2024. The Author(s).)

Dual-specificity tyrosine kinase 1A (DYRK1A) is a member of the CMGC family that is linked to a multitude of neuronal development pathways. Both overexpression and insufficiency of this gene are associated with many recognizable disorders, including Down syndrome and DYRK1A-related intellectual disability syndrome which is characterized by distinct physical features with microcephaly and global developmental delay. We report a case of DYRK1A-related intellectual disability syndrome caused by a novel mutation., Competing Interests: The authors declare that they have no conflicts of interest., (Copyright © 2024 Fiona Whitaker and Alvaro Serrano.)

Introduction The Advanced Trauma Life Support (ATLS) Course is a two-day long medical training course developed by the American College of Surgeons (ACS) to help train and prepare healthcare providers to care for severely injured patients. The coronavirus disease 2019 (COVID-19) pandemic has resulted in the modification or cancellation of many education programs across the world. At the University of South Florida's Center for Advanced Medical Learning and Simulation (CAMLS) two different models of ATLS were delivered in response to the COVID-19 pandemic with both models utilizing the ACS's online mobile ATLS (mATLS). In this study three different models of ATLS delivered by USF CAMLS between 2019 and 2020 were compared to determine if there were any impacts on the education and functionality of the ATLS course between the three different models of ATLS: a baseline ATLS course, an augmented ATLS course that used mATLS, and an ATLS course that used mATLS as a replacement for in-person lectures. Material and methods To compare the three models of ATLS delivery, a total of six ATLS courses were studied: a baseline face-to-face ATLS course from June 2019, two Mobile ATLS (mATLS) courses from September 2020, and three augmented ATLS courses that contained both face-to-face and mATLS delivery from October, November and December 2020. The only differences between the traditional ATLS courses from 2020 and the pre-COVID ATLS course from 2019 were that the courses from 2020 utilized mATLS and that the course days were longer due to cleaning time. These courses were selected to have a non-significant difference in the number of learners in each model of ATLS course. The data that were collected from these courses included: post-test results from learners, learner feedback surveys, and interviews with the ATLS Course Director, ATLS Course Coordinator, and the Educational Coordinator. Results The only courses with significant differences in the post-test mean scores were for the baseline ATLS course compared to the mATLS courses. The augmented courses showed similar post-test performance to the mATLS courses. Students viewed the courses favorably with the only major complaint between the 2019 and the 2020 courses being a high amount of downtime for the 2020 courses due to time required to disinfect skill stations and equipment. The main difficulties for the ATLS Course Director, ATLS Course Coordinator, and the Educational Coordinator with the ATLS courses in 2020 were concerned with challenges from COVID-19, like social distancing, and not with mATLS or the shortened instruction time with the hybrid model. Discussion This preliminary study analyzed three delivery models of ATLS. The mATLS may be able to replace in-person lectures of ATLS courses as courses using alternative delivery formats showed post-test scores as good or better than the baseline face-to-face course., Competing Interests: The authors have declared that no competing interests exist., (Copyright © 2021, Dyer et al.)

Exposure of monocytes to lipopolysaccharide (LPS) during, but not after, adherence purification increased their cytolytic activity in short-term 51Cr-release assays against K562 target cells. In the absence of LPS only a minority of monocytes could be recovered by adherence. With 1 ng/ml to 10 micrograms/ml LPS present during the 1-hr adherence procedure, however, monocytes spread more extensively on serum-coated plastic and glass surfaces and virtually all of the monocytes in a mononuclear leukocyte preparation were recovered in the adherent fraction. While increasing the recovery of monocytes threefold, LPS exposure during adherence also increased monocyte purity as assessed by peroxidase staining, morphology, and indirect immunofluorescence with monoclonal Mo2. The proportion of Leu-11-positive NK cells in the adherent fraction did not change. Depletion of NK cells by treatment with anti-Leu-11b and complement eliminated cytolytic activity from the nonadherent, but not from the adherent, fraction isolated with LPS. Thus, addition of LPS during adherence produced a monocyte preparation with enhanced cytolytic activity not attributable to NK contaminants. To test whether LPS caused production of lymphokines that activate monocytes, we tested supernatants of unseparated mononuclear leukocytes for the capacity to stimulate purified monocytes for cytolysis. Such supernatants stimulated monocytes more effectively than LPS alone. We conclude that LPS stimulates monocytes for cytolysis most effectively during adherence purification because LPS allows the recovery of weakly adherent monocytes with high cytolytic capacity; also, LPS may stimulate production of lymphokines that further augment monocyte cytolytic activity.