Explore the vast range of titles available.

We observed infection rates associated with the LifeSite Hemodialysis Access System, a novel dialysis device consisting of 2 subcutaneously implanted valves accessed by repeated use of fibrous tissue tracts, of 4.8 total infections and 8.1 first episodes per 1000 patient-days. These rates are higher than those observed elsewhere, which may be related to use of the device in a population of chronically ill patients, to the learning curve associated with use of the device, or to inherent qualities of the device.

Morphologies and size-frequency distributions of impact craters on Mercury imaged during MESSENGER's first flyby elucidate the planet's geological history. Plains interior to the Caloris basin displaying color and albedo contrasts have comparable crater densities and therefore similar ages. Smooth plains exterior to Caloris exhibit a crater density ~40% less than on interior plains and are thus volcanic and not Caloris impact ejecta. The size distribution of smooth-plains craters matches that of lunar craters postdating the Late Heavy Bombardment, implying that the plains formed no earlier than 3.8 billion years ago (Ga). At diameters less than or equal to 8 to 10 kilometers, secondary impact craters on Mercury are more abundant than primaries; this transition diameter is much larger than that on the Moon or Mars. A low density of craters on the peak-ring basin Raditladi implies that it may be younger than 1 Ga.

Analysis of craters on Mercury’s oldest, most heavily cratered terrains shows that they were formed 4.0–4.1 billion years ago, and that the planet’s previous geological history was erased, most probably by voluminous volcanism, which may have been triggered by heavy asteroidal bombardment at that time. A fresh face for Mercury The most heavily cratered terrains on Mercury exhibit a lower density of craters smaller than about 100 km in diameter than on the Moon, a deficit that has been attributed to resurfacing by formation of ancient intercrater plains. Simone Marchi et al . used a crater areal density map based on data from the MESSENGER spacecraft (the colour-coded foreground on cover, with a global surface mosaic in the background) to locate the oldest surfaces on Mercury and interpret the crater populations in the framework of a recent lunar crater chronology. They conclude that the oldest surfaces were emplaced just after the start of the Late Heavy Bombardment 4.0 to 4.1 billion years ago. The large impact basins, not previously dated, yield a similar surface age. This agreement implies that resurfacing was global and due to volcanism, perhaps aided by heavy bombardment as previously suggested. The most heavily cratered terrains on Mercury have been estimated to be about 4 billion years (Gyr) old 1 , 2 , 3 , 4 , but this was based on images of only about 45 per cent of the surface; even older regions could have existed in the unobserved portion. These terrains have a lower density of craters less than 100 km in diameter than does the Moon 1 , 3 , 5 , an observation attributed to preferential resurfacing on Mercury. Here we report global crater statistics of Mercury’s most heavily cratered terrains on the entire surface. Applying a recent model for early lunar crater chronology 6 and an updated dynamical extrapolation to Mercury 7 , we find that the oldest surfaces were emplaced just after the start of the Late Heavy Bombardment (LHB) about 4.0–4.1 Gyr ago. Mercury’s global record of large impact basins 8 , which has hitherto not been dated, yields a similar surface age. This agreement implies that resurfacing was global and was due to volcanism, as previously suggested 1 , 5 . This activity ended during the tail of the LHB, within about 300–400 million years after the emplacement of the oldest terrains on Mercury. These findings suggest that persistent volcanism could have been aided by the surge of basin-scale impacts during this bombardment.

During its first two flybys of Mercury, the MESSENGER spacecraft acquired images confirming that pervasive volcanism occurred early in the planet's history. MESSENGER's third Mercury flyby revealed a 290-kilometer-diameter peak-ring impact basin, among the youngest basins yet seen, having an inner floor filled with spectrally distinct smooth plains. These plains are sparsely cratered, postdate the formation of the basin, apparently formed from material that once flowed across the surface, and are therefore interpreted to be volcanic in origin. An irregular depression surrounded by a halo of bright deposits northeast of the basin marks a candidate explosive volcanic vent larger than any previously identified on Mercury. Volcanism on the planet thus spanned a considerable duration, perhaps extending well into the second half of solar system history.

The beneficial health properties of the Mediterranean diet are well recognized. The principle source of fat in Mediterranean diet is extra-virgin olive oil (EVOO). Oleocanthal (OC) is a naturally occurring minor phenolic compound isolated from EVOO, which has shown a potent anti-inflammatory activity, by means of its ability to inhibit the cyclooxygenase (COX) enzymes COX-1 and COX-2. A large body of evidence indicates that phenols exhibit anticancer activities. The aim of the present study was to evaluate the potential anticancer effects of OC in hepatocellular carcinoma (HCC) and colorectal carcinoma (CRC) models. A panel of human HCC (HepG2, Huh7, Hep3B and PLC/PRF/5) and CRC (HT29, SW480) cell lines was used. Cells were treated with OC, and cell viability and apoptosis were evaluated. Compared with classical commercially available COX inhibitors (ibuprofen, indomethacin, nimesulide), OC was more effective in inducing cell growth inhibition in HCC and CRC cells. Moreover, OC inhibited colony formation and induced apoptosis, as confirmed by PARP cleavage, activation of caspases 3/7 and chromatin condensation. OC treatment in a dose dependent-manner induced expression of γH2AX, a marker of DNA damage, increased intracellular ROS production and caused mitochondrial depolarization. Moreover, the effects of OC were suppressed by the ROS scavenger N-acetyl-L-cysteine. Finally, OC was not toxic in primary normal human hepatocytes. In conclusion, OC treatment was found to exert a potent anticancer activity against HCC and CRC cells. Taken together, our findings provide preclinical support of the chemotherapeutic potential of EVOO against cancer.

Artificial intelligence (AI) models to identify heart failure (HF) with preserved ejection fraction (HFpEF) based on deep-learning of echocardiograms could help address under-recognition in clinical practice, but they require extensive validation, particularly in representative and complex clinical cohorts for which they could provide most value. In this study enrolling patients with HFpEF (cases; n = 240), and age, sex, and year of echocardiogram matched controls (n = 256), we compare the diagnostic performance (discrimination, calibration, classification, and clinical utility) and prognostic associations (mortality and HF hospitalization) between an updated AI HFpEF model (EchoGo Heart Failure v2) and existing clinical scores (H2FPEF and HFA-PEFF). The AI HFpEF model and H2FPEF score demonstrate similar discrimination and calibration, but classification is higher with AI than H2FPEF and HFA-PEFF, attributable to fewer intermediate scores, due to discordant multivariable inputs. The continuous AI HFpEF model output adds information beyond the H2FPEF, and integration with existing scores increases correct management decisions. Those with a diagnostic positive result from AI have a two-fold increased risk of the composite outcome. We conclude that integrating an AI HFpEF model into the existing clinical diagnostic pathway would improve identification of HFpEF in complex clinical cohorts, and patients at risk of adverse outcomes. Whether deep learning of echocardiograms can improve recognition of heart failure with preserved ejection fraction (HFpEF) compared to clinical scores remains uncertain. Here the authors show that such a model would improve identification of HFpEF and patients at risk of adverse outcomes.

Military personnel commonly experience post-traumatic stress disorder (PTSD) and mild traumatic brain injury (mTBI), both of which are associated with premature mortality. The present study examined two factors that may play a role in premature mortality--impulsivity and risk-taking behaviors--in a sample of 234 veterans screening positive for PTSD, mTBI, PTSD + mTBI, and controls. Analyses of variance demonstrated that veterans with PTSD, regardless of mTBI status, reported engaging in more frequent risky behaviors and reported a greater tendency to engage in impulsive behaviors when in a negative affective state. They also reported more premilitary delinquent behaviors and more suicide-related behaviors than controls. The present study highlights associations between impulsivity, risk-taking behaviors, and PTSD, and suggests continuity across the lifespan in terms of a predisposition to engage in impulsive and/or risky behaviors. Thorough evaluation of impulsivity and potentially risky behaviors is important in clinical settings to guide interventions and reduce the mortality and public health impact of high-risk behaviors in veterans.

Some of the longest and most comprehensive marine ecosystem monitoring programs were established in the Gulf of Alaska following the environmental disaster of the  Exxon Valdez  oil spill over 30 years ago. These monitoring programs have been successful in assessing recovery from oil spill impacts, and their continuation decades later has now provided an unparalleled assessment of ecosystem responses to another newly emerging global threat, marine heatwaves. The 2014–2016 northeast Pacific marine heatwave (PMH) in the Gulf of Alaska was the longest lasting heatwave globally over the past decade, with some cooling, but also continued warm conditions through 2019. Our analysis of 187 time series from primary production to commercial fisheries and nearshore intertidal to offshore oceanic domains demonstrate abrupt changes across trophic levels, with many responses persisting up to at least 5 years after the onset of the heatwave. Furthermore, our suite of metrics showed novel community-level groupings relative to at least a decade prior to the heatwave. Given anticipated increases in marine heatwaves under current climate projections, it remains uncertain when or if the Gulf of Alaska ecosystem will return to a pre-PMH state.

MESSENGER observations from Mercury orbit reveal that a large contiguous expanse of smooth plains covers much of Mercury's high northern latitudes and occupies more than 6% of the planet's surface area. These plains are smooth, embay other landforms, are distinct in color, show several flow features, and partially or completely bury impact craters, the sizes of which indicate plains thicknesses of more than 1 kilometer and multiple phases of emplacement. These characteristics, as well as associated features, interpreted to have formed by thermal erosion, indicate emplacement in a flood-basalt style, consistent with x-ray spectrometric data indicating surface compositions intermediate between those of basalts and komatiites. The plains formed after the Caloris impact basin, confirming that volcanism was a globally extensive process in Mercury's post—heavy bombardment era.