The high lateral resolution and sensitivity of the NanoSIMS 50 and 50L series of dynamic SIMS instruments have enabled numerous scientific advances over the past 25 years. Here, we report on the NanoSIMS-HR, the first major upgrade to the series, and analytical tests in a suite of sample types, including an aluminum sample containing silicon crystals, microalgae, and plant roots colonized with a symbiotic fungus. Significant improvements have been made in the Cs ion source, high voltage (HV) control, stage reproducibility, and other aspects of the instrument that affect performance.
View Article and Find Full Text PDFBackground And Objectives: In 2017, our French 1671-bed university hospital opened a 12-bed unit for very short stays, post-emergency (unit of transitory admission in geriatric [UTAG] area), dedicated to frail patients older than 75 years requiring short-term care. We sought to investigate whether this new organization's shortened length of stay (LOS) was associated or not with a higher rate of readmission.
Methods: We conducted a retrospective descriptive study based on the daily activity of the UTAG over 6 months including all patients consecutively hospitalized in the unit via the computerized medical file of the hospital.
In-situ oxygen three-isotope analyses of chondrules and isolated olivine grains in the Paris (CM) chondrite were conducted by secondary ion mass spectrometry (SIMS). Multiple analyses of olivine and/or pyroxene in each chondrule show indistinguishable ΔO values, except for minor occurrences of relict olivine grains (and one low-Ca pyroxene). A mean ΔO value of these homogeneous multiple analyses was obtained for each chondrule, which represent oxygen isotope ratios of the chondrule melt.
View Article and Find Full Text PDFDynamic models of the protoplanetary disk indicate there should be large-scale material transport in and out of the inner Solar System, but direct evidence for such transport is scarce. Here we show that the εTi-εCr-ΔO systematics of large individual chondrules, which typically formed 2 to 3 My after the formation of the first solids in the Solar System, indicate certain meteorites (CV and CK chondrites) that formed in the outer Solar System accreted an assortment of both inner and outer Solar System materials, as well as material previously unidentified through the analysis of bulk meteorites. Mixing with primordial refractory components reveals a "missing reservoir" that bridges the gap between inner and outer Solar System materials.
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