Limestone assimilation and skarn formation are important processes in magmatic systems emplaced within carbonate-rich crust and can affect the composition of the magma and that of associated volcanic ...gas. In this study we focus on marble and calc-silicate (skarn) xenoliths from contact reactions between magma and carbonate wall-rock of the Vesuvius volcanic system. We present new elemental and C-O isotope data for marble and skarn xenoliths as well as for igneous rocks collected from the AD 79 (Pompeii) and AD 472 (Pollena) eruptions. The igneous samples have consistently high δ18O values (9.3 to 10.8‰), but low H2O contents (≤1.5%), indicating that magma–crust interaction prior to eruption took place. The marble xenoliths, in turn, record initial decarbonation reactions and fluid-mass exchange in their textures and δ13C and δ18O ranges, while the skarn xenoliths reflect prolonged magma–carbonate interaction and intense contact metamorphism. Skarn-xenoliths record Ca and Mg release from the original carbonate and uptake of Al and Si and span the full δ18O data range from un-metamorphosed carbonate (>18‰) to values typical for Vesuvius magmatic rocks (~7.5‰), which implies that skarn xenoliths comprise carbonate and magmatic components. Textural and chemical evidence suggest that direct carbonate dissolution into the host magmas occurred as well as post-metamorphic skarn recycling, resulting in progressive Ca and Mg liberation from the skarn xenoliths into the magma. Magma–carbonate interaction is an additional source of CO2 during carbonate break-down and assimilation and we calculate the amount of extra volatile components likely liberated by contact metamorphic reactions before and during the investigated eruptions. We find that the extra CO2 added into the volcanic system could have outweighed the magmatic CO2 component by ≥ factor seven and thus likely increased the intensity of both the Pompeii and the Pollena eruptive events.
•New stable isotope data from igneous rocks and contact-metamorphic skarn-type xenoliths from the Vesuvius volcanic system.•Different mechanisms of magma–crust interaction, such as carbonate dissolution and skarn recycling, are relevant processes.•A formulation to approximate the potential volumes of magmatic versus non-magmatic CO2 is presented.
Here, we report on the Quaternary Volsci Volcanic Field (VVF, central Italy). In light of new
40
Ar/
39
Ar geochronological data and compositional characterization of juvenile eruptive products, we ...refine the history of VVF activity, and outline the implications on the pre-eruptive magma system and the continental subduction processes involved. Different from the nearby volcanic districts of the Roman and Campanian Provinces, the VVF was characterized by small-volume (0.01–0.1 km
3
) eruptions from a network of monogenetic centers (mostly tuff rings and scoria cones, with subordinate lava occurrences), clustered along high-angle faults of lithospheric depth. Leucite-bearing, high-K (HKS) magmas (for which we report for the first time the phlogopite phenocryst compositions) mostly fed the early phase of activity (∼761–539 ka), then primitive, plagioclase-bearing (KS) magmas appeared during the climactic phase (∼424–349 ka), partially overlapping with HKS ones, and then prevailed during the late phase of activity (∼300–231 ka). The fast ascent of primitive magma batches is typical of a tectonically controlled volcanic field, where the very low magma flux is a passive byproduct of regional tectonic strain. We suggest that the dominant compressive stress field acting at depth was accompanied by an extensional regime in the upper crust, associated with the gravity spreading of the Apennine chain, allowing the fast ascent of magma from the mantle source with limited stationing in shallow reservoirs.
Abstract Context Over a million individuals in the United States experience homelessness annually and homeless individuals die at a higher rate than domiciled peers. Homeless individuals often have ...unique experiences at the end of life (EOL). Objectives This study examined the symptoms experienced by homeless individuals nearing the EOL and explored social background, attitudes, and experiences. Methods Investigators conducted surveys of homeless individuals approaching the EOL at a medical respite home. Eligibility required a serious medical condition and for the patient's medical provider to answer “no” to the question “Would you be surprised if this patient were not alive in one year?” Interviews explored symptoms using the Memorial Symptom Assessment Survey. Symptoms were compared with those of relevant comparator groups in other studies. Results Participants ( n = 20) were young to face the EOL (median age = 58) and suffered high rates of substance use disorders ( n = 18; 90%) and psychiatric diagnoses ( n = 16; 80%). Symptom frequency was high, especially as regarded pain and psychological symptoms. Previous experience with death among family and peers was universal ( n = 20; 100%). Mistrust of others' decisions about the EOL was common, as was concern about receiving too little ( n = 11; 55%) or too much ( n = 8; 40%) care at the EOL. The frequency of symptoms was higher than in three comparator studies and those studies' subgroups ( P < 0.01 for each comparison). Conclusion Homeless individuals may experience a high frequency of pain and other symptoms as they approach the EOL. Care for such individuals may require a tailored approach.
We integrate 10 new with five published 40Ar/39Ar age determinations, both on primary volcanic deposits and on detrital sanidine, which provide precise geochronologic control on the Marine Isotope ...Stage (MIS) 5.5 and MIS 5.3 sea‐level indicators that occur at three coastal caves in a tectonically stable region of the central Tyrrhenian Sea of Italy. The age of a Strombus‐bearing bioclastic conglomerate, associated with a tidal notch occurring at 9.5 m a.s.l. at Cape Circeo, is constrained to between 121.5 ± 5.8 and 116.2 ± 1.2 ka. Moreover, backbeach deposits intercalated in the sedimentary filling of Guattari and Capre coastal caves are directly correlated with a tidal notch at ∼2.5 m associated with another bioclastic conglomerate at Cape Circeo and dated to 110.4 ± 1.4–104.9 ± 0.9 ka. The latter deposit is also correlated with the adjacent marine terrace, occurring at 3–5 m on the coast between Capes Circeo and Anzio, for which a maximum age of 100.7 ± 6.6 ka was previously reported. These data provide evidence for a maximum sea level around 9.5 m above the present sea level and a duration of MIS 5.5 highstand until 116 ka, in agreement with estimates from other regions in the world. In contrast, they suggest a maximum sea level during MIS 5.3 highstand that is similar to the present level, and only ∼7 m lower than the MIS 5.5 highstand, challenging the reconstructions of the MIS 5 ice‐sheet volumes and derived global sea levels that are based on benthic oxygen isotope records.
Opioid overdoses killed 47,600 people in the United States in 2017. Despite increasing availability of office-based addiction treatment programs, the prevalence of opioid overdose is historically ...high and disproportionately affects vulnerable populations, including people experiencing homelessness. Despite availability of effective treatment, many at greatest risk of death from overdose experience myriad barriers to care. Launched in 2018, the Community Care in Reach mobile health initiative uses a data-driven approach to bring harm reduction and medication for opioid use disorder directly to those at highest risk of near-term death. Proof-of-concept results suggest that mobile addiction services may serve as a model for expanding access to addiction care for the most vulnerable.
A key facet of epithelial differentiation is the assembly of actin-based protrusions known as microvilli, which amplify apical membrane surface area for various cell functions. To probe mechanisms of ...microvillus assembly, we developed a protocol using spinning disk confocal microscopy to directly visualize microvillus biogenesis on the surface of cultured porcine kidney epithelial cell monolayers engineered to express fluorescent proteins. This protocol offers access to the molecular details of individual protrusion growth events at high spatiotemporal resolution.
For complete details on the use and execution of this protocol, please refer to Gaeta et al. (2021).
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•Directly visualize microvillus growth events using spinning disc confocal microscopy•Procedure for stable cell line generation in LLC-PK1-CL4 cells•Analysis of microvillus growth dynamics and tip targeted proteins
A key facet of epithelial differentiation is the assembly of actin-based protrusions known as microvilli, which amplify apical membrane surface area for various cell functions. To probe mechanisms of microvillus assembly, we developed a protocol using spinning disk confocal microscopy to directly visualize microvillus biogenesis on the surface of cultured porcine kidney epithelial cell monolayers engineered to express fluorescent proteins. This protocol offers access to the molecular details of individual protrusion growth events at high spatiotemporal resolution.
We present new 40Ar/39Ar data which allow us to refine the recurrence time for the most recent eruptive activity occurred at Colli Albani Volcanic District (CAVD) and constrain its geographic area. ...Time elapsed since the last eruption (36 kyr) overruns the recurrence time (31 kyr) in the last 100 kyr. New interferometric synthetic aperture radar data, covering the years 1993–2010, reveal ongoing inflation with maximum uplift rates (>2 mm/yr) in the area hosting the most recent (<200 ka) vents, suggesting that the observed uplift might be caused by magma injection within the youngest plumbing system. Finally, we frame the present deformation within the structural pattern of the area of Rome, characterized by 50 m of regional uplift since 200 ka and by geologic evidence for a recent (<2000 years) switch of the local stress‐field, highlighting that the precursors of a new phase of volcanic activity are likely occurring at the CAVD.
Key Points
The time elapsed since the last eruption overruns the recurrence time in the last 100 kyr
Maximum uplift rates (>2 mm/yr) are concetrated in the area hosting the most recent (<200 ka) vents
We suggest that the observed uplift might be the result of magma injection within the youngest plumbing system of the volcano
The quality of the Colli Albani volcanic soils has certainly contributed to the vine cultivars hence the name of one of the oldest wines (i.e., Alban wine). The alkali up to 15 wt%, SiO2 ≤ 52 wt% and ...the emplacement at high temperature (≤ 600 °C) are the bedrock features that have deeply influenced the soil-forming processes in the vineyards. However, the peculiar features of the Colli Albani soils are not well known. Field survey and textural, mineralogical, and chemical data obtained with SEM, EMP, XRD, and ICP-OES were used to characterize the vineyard soils of the Colli Albani. Leucite (Lct)-bearing soils and quartz (Qz)-bearing soils occur in the studied vineyard. The Qz-bearing soils represent more weathered volcanic material, depleted in primary minerals and enriched in clays, which show a lower cation exchange capacity (CEC) than the Lct-bearing soils. CEC is a misleading definition for the Colli Albani soils because the base cation mobility in the vineyard is independent from clay mineral enrichment in the soil. Actually, the release of K, Na, Ca, and Mg depends by (i) the complete dissolution of leucite and analcime, (ii) the oxy-reaction affecting the phlogopite, which releases K + Mg, and (iii) the incongruent dissolution of clinopyroxene characterized by the “gothic texture.” This texture highlights the capacity of clinopyroxene to release Ca and Mg in volcanic soils. Quantification of the texture and abundance of the primary minerals are mandatory for the management of the vineyard soils in the Colli Albani and, in general, it is significative for the vineyards in volcanic areas.
Multi-echo Chemical Shift–Encoded (CSE) methods for Fat-Water quantification are growing in clinical use due to their ability to estimate and correct some confounding effects. State of the art CSE ...water/fat separation approaches rely on a multi-peak fat spectrum with peak frequencies and relative amplitudes kept constant over the entire MRI dataset. However, the latter approximation introduces a systematic error in fat percentage quantification in patients where the differences in lipid chemical composition are significant (such as for neuromuscular disorders) because of the spatial dependence of the peak amplitudes. The present work aims to overcome this limitation by taking advantage of an unsupervised clusterization-based approach offering a reliable criterion to carry out a data-driven segmentation of the input MRI dataset into multiple regions. Results established that the presented algorithm is able to identify at least 4 different partitions from MRI dataset under which to perform independent self-calibration routines and was found robust in NMD imaging studies (as evaluated on a cohort of 24 subjects) against latest CSE techniques with either calibrated or non-calibrated approaches. Particularly, the PDFF of the thigh was more reproducible for the quantitative estimation of pathological muscular fat infiltrations, which may be promising to evaluate disease progression in clinical practice.
Approximately 356 000 people stay in homeless shelters nightly in the United States. They have high risk of contracting coronavirus disease 2019 (COVID-19).
To assess the estimated clinical outcomes, ...costs, and cost-effectiveness associated with strategies for COVID-19 management among adults experiencing sheltered homelessness.
This decision analytic model used a simulated cohort of 2258 adults residing in homeless shelters in Boston, Massachusetts. Cohort characteristics and costs were adapted from Boston Health Care for the Homeless Program. Disease progression, transmission, and outcomes data were taken from published literature and national databases. Surging, growing, and slowing epidemics (effective reproduction numbers Re, 2.6, 1.3, and 0.9, respectively) were examined. Costs were from a health care sector perspective, and the time horizon was 4 months, from April to August 2020.
Daily symptom screening with polymerase chain reaction (PCR) testing of individuals with positive symptom screening results, universal PCR testing every 2 weeks, hospital-based COVID-19 care, alternative care sites (ACSs) for mild or moderate COVID-19, and temporary housing were each compared with no intervention.
Cumulative infections and hospital-days, costs to the health care sector (US dollars), and cost-effectiveness, as incremental cost per case of COVID-19 prevented.
The simulated population of 2258 sheltered homeless adults had a mean (SD) age of 42.6 (9.04) years. Compared with no intervention, daily symptom screening with ACSs for pending tests or confirmed COVID-19 and mild or moderate disease was associated with 37% fewer infections (1954 vs 1239) and 46% lower costs ($6.10 million vs $3.27 million) at an Re of 2.6, 75% fewer infections (538 vs 137) and 72% lower costs ($1.46 million vs $0.41 million) at an Re of 1.3, and 51% fewer infections (174 vs 85) and 51% lower costs ($0.54 million vs $0.26 million) at an Re of 0.9. Adding PCR testing every 2 weeks was associated with a further decrease in infections; incremental cost per case prevented was $1000 at an Re of 2.6, $27 000 at an Re of 1.3, and $71 000 at an Re of 0.9. Temporary housing with PCR every 2 weeks was most effective but substantially more expensive than other options. Compared with no intervention, temporary housing with PCR every 2 weeks was associated with 81% fewer infections (376) and 542% higher costs ($39.12 million) at an Re of 2.6, 82% fewer infections (95) and 2568% higher costs ($38.97 million) at an Re of 1.3, and 59% fewer infections (71) and 7114% higher costs ($38.94 million) at an Re of 0.9. Results were sensitive to cost and sensitivity of PCR and ACS efficacy in preventing transmission.
In this modeling study of simulated adults living in homeless shelters, daily symptom screening and ACSs were associated with fewer severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) infections and decreased costs compared with no intervention. In a modeled surging epidemic, adding universal PCR testing every 2 weeks was associated with further decrease in SARS-CoV-2 infections at modest incremental cost and should be considered during future surges.
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