Magnet hospitals, a concept developed in the U.S., have been associated with improved nurse recruitment and retention, and better patient outcomes. Magnet principles may be useful to address ...workforce challenges in European hospitals, but they have not been implemented or evaluated on a large scale in the European hospital context.
This study aims to explore the initial phase of implementing Magnet principles in 11 acute care hospitals in six European countries. The specific objectives of the study were to investigate the type of work that characterises the early phase of implementation and how implementation leaders engage with their context.
A multinational qualitative study was conducted, with data from 23 semi-structured, one-to-one interviews with implementation leaders in 11 acute care hospitals in six European countries. Thematic analyses guided the analysis of data.
Three themes of core work processes during the early phase of implementing Magnet principles in European hospitals were identified. The first theme, ‘Creating space for Magnet’, describes how work was directed towards creating both political and organisational space for the project. The second theme, ‘Framing to fit: understanding and interpreting Magnet principles’, describes the translational work to understand what the Magnet model entails and how it relates to the local hospital context. Finally, the third theme, ‘Calibrating speed and dose’, describes the strategic work of considering internal and external factors to adjust the process of implementation.
The first phase of implementation was characterised by conceptual and relational work; translating the Magnet concepts, considering the fit into existing structures and practices and making space for Magnet in the local context. Understanding the local context played an important role in shaping and guiding the navigation of professional and organisational tensions. Hospitals employed diverse strategies to either emphasise or downplay the role of nurses and nursing to facilitate progress in the implementation.
The Mars Science Laboratory rover Curiosity found host rocks of basaltic composition and alteration assemblages containing clay minerals at Yellowknife Bay, Gale Crater. On the basis of the observed ...host rock and alteration minerals, we present results of equilibrium thermochemical modeling of the Sheepbed mudstones of Yellowknife Bay in order to constrain the formation conditions of its secondary mineral assemblage. Building on conclusions from sedimentary observations by the Mars Science Laboratory team, we assume diagenetic, in situ alteration. The modeling shows that the mineral assemblage formed by the reaction of a CO2‐poor and oxidizing, dilute aqueous solution (Gale Portage Water) in an open system with the Fe‐rich basaltic‐composition sedimentary rocks at 10–50°C and water/rock ratio (mass of rock reacted with the starting fluid) of 100–1000, pH of ~7.5–12. Model alteration assemblages predominantly contain phyllosilicates (Fe‐smectite, chlorite), the bulk composition of a mixture of which is close to that of saponite inferred from Chemistry and Mineralogy data and to that of saponite observed in the nakhlite Martian meteorites and terrestrial analogues. To match the observed clay mineral chemistry, inhomogeneous dissolution dominated by the amorphous phase and olivine is required. We therefore deduce a dissolving composition of approximately 70% amorphous material, with 20% olivine, and 10% whole rock component.
Key Points
Thermochemical modelling constrains the secondary minerals in Gale Crater
Inhomogeneous dissolution of amorphous and olivine phases forms clay, magnetite
Formed by reaction of CO2‐poor, oxidising brine with basaltic sedimentary rocks
Terminal grains from C2063,1,154,1,0 (Track 154) and C2061,1,113,5 (Track 113) from the Stardust collection of Comet Wild2's coma have been studied by TEM and NanoSIMS. Terminal grain 2 of ...C2063,1,154,1,0 consists of an Al-rich diopside (En 97–99%, Al2O3 9–11wt%), pigeonite (En 85% Wo 15% with TiO2 and Al2O3 contents of 0.5 and 5.2wt%) and minor forsterite and enstatite. The mineral assemblage and Al-rich, Ti-poor composition of the grain are consistent with being a fragment of an Al-rich chondrule, similar to those present in carbonaceous chondrites. The oxygen isotopic composition of the C2063,1,154,1,0 grain was determined by NanoSIMS analyses and found to be δ17O −10.6±5.7‰, δ18O −7.5±2.5‰ and δ17O +1.4±4.3‰, δ18O −6.5±1.6‰ (1σ errors) for the two sections. These figures are distinct from CAIs and consistent with an origin as Al-rich chondrule fragments. Terminal grain 5 of C2061,1,113,5 consists of low Ca pyroxene En 86–87% Fs 10–11% Wo 3–4% and ≤2wt% Al2O3 and in one section 5–10% of a Na-rich silicate phase. This assemblage may be a fragment of a low-Ca pyroxene-bearing chondrule and mesostasis. The original chondrule diameter for the C2063,1,154,1,0 and C2061,1,113,5 samples, by analogy with carbonaceous chondrite chondrules, might have been in the range 0.2–1.0mm. If they were of that size, then the presence of large grains of high temperature material (e.g. ≥1500K for such refractory assemblages) could be explained through commonly invoked models of radial drift from inner to outer Solar System, but only if the chondrules were first fragmented to dust within the inner Solar System. An alternative scenario is that some chondrule formation was associated with high temperature processing and planetesimals in the outer Solar System.
► First identification of an Al-rich chondrule fragment in Comet Wild2. ► Mineralogy and oxygen isotope analyses by NanoSIMS indicate affinities to Al-rich chondrules from carbonaceous chondrites. ► The presence of refractory, high T chondrule fragments within a comet is consistent with models of the early Solar System. ► The high temperature in outer Solar System requires migration of large particle from inner to outer Solar System.
At Gale crater, Mars, ChemCam acquired its first laser-induced breakdown spectroscopy (LIBS) target on Sol 13 of the landed portion of the mission (a Sol is a Mars day). Up to Sol 800, more than 188 ...000 LIBS spectra were acquired on more than 5800 points distributed over about 650 individual targets. We present a comprehensive review of ChemCam scientific accomplishments during that period, together with a focus on the lessons learned from the first use of LIBS in space. For data processing, we describe new tools that had to be developed to account for the uniqueness of Mars data. With regard to chemistry, we present a summary of the composition range measured on Mars for major-element oxides (SiO
2
, TiO
2
, Al
2
O
3
, FeO
T
, MgO, CaO, Na
2
O, K
2
O) based on various multivariate models, with associated precisions. ChemCam also observed H, and the non-metallic elements C, O, P, and S, which are usually difficult to quantify with LIBS. F and Cl are observed through their molecular lines. We discuss the most relevant LIBS lines for detection of minor and trace elements (Li, Rb, Sr, Ba, Cr, Mn, Ni, and Zn). These results were obtained thanks to comprehensive ground reference datasets, which are set to mimic the expected mineralogy and chemistry on Mars. With regard to the first use of LIBS in space, we analyze and quantify, often for the first time, each of the advantages of using stand-off LIBS in space: no sample preparation, analysis within its petrological context, dust removal, sub-millimeter scale investigation, multi-point analysis, the ability to carry out statistical surveys and whole-rock analyses, and rapid data acquisition. We conclude with a discussion of ChemCam performance to survey the geochemistry of Mars, and its valuable support of decisions about selecting where and whether to make observations with more time and resource-intensive tools in the rover's instrument suite. In the end, we present a bird's-eye view of the many scientific results: discovery of felsic Noachian crust, first observation of hydrated soil, discovery of manganese-rich coatings and fracture fills indicating strong oxidation potential in Mars' early atmosphere, characterization of soils by grain size, and wide scale mapping of sedimentary strata, conglomerates, and diagenetic materials.
At Gale crater, Mars, ChemCam acquired its first laser-induced breakdown spectroscopy (LIBS) target on Sol 13 of the landed portion of the mission (a Sol is a Mars day).
— Aluminum foils of the Stardust cometary dust collector are peppered with impact features of a wide range of sizes and shapes. By comparison to laboratory shots of known particle dimensions and ...density, using the same velocity and incidence geometry as the Stardust Wild 2 encounter, we can derive size and mass of the cometary dust grains. Using scanning electron microscopy (SEM) of foil samples (both flown on the mission and impacted in the laboratory) we have recognized a range of impact feature shapes from which we interpret particle density and internal structure. We have documented composition of crater residues, including stoichiometric material in 3 of 7 larger craters, by energy dispersive X‐ray microanalysis. Wild 2 dust grains include coarse (>10 μm) mafic silicate grains, some dominated by a single mineral species of density around 3–4 g cm−3 (such as olivine). Other grains were porous, low‐density aggregates from a few nanometers to 100 μm, with an overall density that may be lower than 1 g cm−3, containing mixtures of silicates and sulfides and possibly both alkali‐rich and mafic glass. The mineral assemblage is very similar to the most common species reported from aerogel tracks. In one large aggregate crater, the combined diverse residue composition is similar to CI chondrites. The foils are a unique collecting substrate, revealing that the most abundant Wild 2 dust grains were of sub‐micrometer size and of complex internal structure. Impact residues in Stardust foil craters will be a valuable resource for future analyses of cometary dust.
Direct links between carbonaceous chondrites and their parent bodies in the solar system are rare. The Winchcombe meteorite is the most accurately recorded carbonaceous chondrite fall. Its ...pre-atmospheric orbit and cosmic-ray exposure age confirm that it arrived on Earth shortly after ejection from a primitive asteroid. Recovered only hours after falling, the composition of the Winchcombe meteorite is largely unmodified by the terrestrial environment. It contains abundant hydrated silicates formed during fluid-rock reactions, and carbon- and nitrogen-bearing organic matter including soluble protein amino acids. The near-pristine hydrogen isotopic composition of the Winchcombe meteorite is comparable to the terrestrial hydrosphere, providing further evidence that volatile-rich carbonaceous asteroids played an important role in the origin of Earth's water.
Abstract
The objective was to test the hypothesis that the selective content of mRNA encoding proteins responsible for prolactin and ACTH synthesis would be reduced in the pituitaries of beef steers ...randomly assigned to graze (89 to 105 d) either high toxic endophyte-infected tall fescue (HE; 0.746 μg/g ergot alkaloids; 5.7 ha; n = 10; BW = 267 ± 14.5 kg) or low toxic endophyte tall fescue–mixed pasture (LE; 0.023 μg/g ergot alkaloids; 5.7 ha; n = 9; BW = 266 ± 10.9 kg). As previously reported, HE steers had lower final BW (7.4%), ADG (31%), and serum prolactin concentrations (90%) than LE steers, and greater capacity for hepatic amino acid-derived gluconeogenesis. From these same steers, total RNA was isolated from whole pituitaries, semi-quantitative reverse-transcription PCR analyses (RT-PCR) were conducted, and the relative content of mRNA for proteins associated with prolactin and ACTH synthesis was compared by ANOVA using the GLM procedure of SAS. The mRNA content of 3 selected reference genes (ACTB, beta-actin; PPIA, peptidylprolyl isomerase A; and UBC, ubiquitin C) was not affected by treatment (P ≥ 0.42) and the geometric mean of their content was used for normalization of targeted mRNA. Regarding prolactin synthesis, mRNA content of DRD2 (P < 0.01; dopamine receptor D2), POU1F1 (P < 0.05; POU class 1 homeobox 1, a.k.a. PIT-1, a transcription factor of PRL expression) and PRL (P < 0.01; prolactin) was reduced in HE vs. LE steers, whereas l-PRLR (P < 0.07; long-form of the prolactin receptor) mRNA content tended to be reduced and mRNA content of s-PRLR (short-form of the prolactin receptor) was not affected (P = 0.21). Moreover, mRNA content of GAL and VIP (galanin and vasoactive intestinal peptide, respectively; both involved in stimulation of prolactin release) was decreased (P < 0.05) in HE steers. Regarding ACTH synthesis, POMC (proopiomelanocortin, precursor polypeptide for ACTH) and PCSK1 (proprotein convertase subtilisin/kexin type 1, cleaves ACTH from POMC) were both reduced (P < 0.01) in HE steers. We conclude that summer-long grazing of endophyte-infected tall fescue inhibits expression of genes responsible for prolactin and ACTH synthesis by the pituitaries of growing beef steers.
COVID-19 has been shown to differently affect various demographic and clinical population subgroups. We aimed to describe trends in absolute and relative COVID-19-related mortality risks across ...clinical and demographic population subgroups during successive SARS-CoV-2 pandemic waves.
We did a retrospective cohort study in England using the OpenSAFELY platform with the approval of National Health Service England, covering the first five SARS-CoV-2 pandemic waves (wave one wild-type from March 23 to May 30, 2020; wave two alpha (B.1.1.7) from Sept 7, 2020, to April 24, 2021; wave three delta (B.1.617.2) from May 28 to Dec 14, 2021; wave four omicron (B.1.1.529) from Dec 15, 2021, to April 29, 2022; and wave five omicron from June 24 to Aug 3, 2022). In each wave, we included people aged 18–110 years who were registered with a general practice on the first day of the wave and who had at least 3 months of continuous general practice registration up to this date. We estimated crude and sex-standardised and age-standardised wave-specific COVID-19-related death rates and relative risks of COVID-19-related death in population subgroups.
18 895 870 adults were included in wave one, 19 014 720 in wave two, 18 932 050 in wave three, 19 097 970 in wave four, and 19 226 475 in wave five. Crude COVID-19-related death rates per 1000 person-years decreased from 4·48 deaths (95% CI 4·41–4·55) in wave one to 2·69 (2·66–2·72) in wave two, 0·64 (0·63–0·66) in wave three, 1·01 (0·99–1·03) in wave four, and 0·67 (0·64–0·71) in wave five. In wave one, the standardised COVID-19-related death rates were highest in people aged 80 years or older, people with chronic kidney disease stage 5 or 4, people receiving dialysis, people with dementia or learning disability, and people who had received a kidney transplant (ranging from 19·85 deaths per 1000 person-years to 44·41 deaths per 1000 person-years, compared with from 0·05 deaths per 1000 person-years to 15·93 deaths per 1000 person-years in other subgroups). In wave two compared with wave one, in a largely unvaccinated population, the decrease in COVID-19-related mortality was evenly distributed across population subgroups. In wave three compared with wave one, larger decreases in COVID-19-related death rates were seen in groups prioritised for primary SARS-CoV-2 vaccination, including people aged 80 years or older and people with neurological disease, learning disability, or severe mental illness (90–91% decrease). Conversely, smaller decreases in COVID-19-related death rates were observed in younger age groups, people who had received organ transplants, and people with chronic kidney disease, haematological malignancies, or immunosuppressive conditions (0–25% decrease). In wave four compared with wave one, the decrease in COVID-19-related death rates was smaller in groups with lower vaccination coverage (including younger age groups) and conditions associated with impaired vaccine response, including people who had received organ transplants and people with immunosuppressive conditions (26–61% decrease).
There was a substantial decrease in absolute COVID-19-related death rates over time in the overall population, but demographic and clinical relative risk profiles persisted and worsened for people with lower vaccination coverage or impaired immune response. Our findings provide an evidence base to inform UK public health policy for protecting these vulnerable population subgroups.
UK Research and Innovation, Wellcome Trust, UK Medical Research Council, National Institute for Health and Care Research, and Health Data Research UK.
The SNC (Shergotty-Nakhla-Chassigny) meteorites have recorded interactions between martian crustal fluids and the parent igneous rocks. The resultant secondary minerals -- which comprise up to 1 ...vol.% of the meteorites -- provide information about the timing and nature of hydrous activity and atmospheric processes on Mars. We suggest that the most plausible models for secondary mineral formation involve the evaporation of low temperature (25 - 150 C) brines. This is consistent with the simple mineralogy of these assemblages -- Fe-Mg-Ca carbonates, anhydrite, gypsum, halite, clays -- and the chemical fractionation of Ca-to Mg-rich carbonate in ALH84001 "rosettes". Longer-lived, and higher temperature, hydrothermal systems would have caused more silicate alteration than is seen and probably more complex mineral assemblages. Experimental and phase equilibria data on carbonate compositions similar to those present in the SNCs imply low temperatures of formation with cooling taking place over a short period of time (e.g. days). The ALH84001 carbonate also probably shows the effects of partial vapourisation and dehydration related to an impact event post-dating the initial precipitation. This shock event may have led to the formation of sulphide and some magnetite in the Fe-rich outer parts of the rosettes. Radiometric dating (K-Ar, Rb-Sr) of the secondary mineral assemblages in one of the nakhlites (Lafayette) suggests that they formed between 0 and 670 Myr, and certainly long after the crystallisation of the host igneous rocks. Crystallisation of ALH84001 carbonate took place 0.5 Gyr after the parent rock. These age ranges and the other research on these assemblages suggest that environmental conditions conducive to near-surface liquid water have been present on Mars periodically over the last 1 Gyr. This fluid activity cannot have been continuous over geological time because in that case much more silicate alteration would have taken place in the meteorite parent rocks and the soluble salts would probably not have been preserved. The secondary minerals could have been precipitated from brines with seawater-like composition, high bicarbonate contents and a weakly acidic nature. The co-existence of siderite (Fe-carbonate) and clays in the nakhlites suggests that the pCO sub(2) level in equilibrium with the parent brine may have been 50 mbar or more. The brines could have originated as flood waters which percolated through the top few hundred meters of the crust, releasing cations from the surrounding parent rocks. The high sulphur and chlorine concentrations of the martian soil have most likely resulted from aeolian redistribution of such aqueously-deposited salts and from reaction of the martian surface with volcanic acid volatiles. The volume of carbonates in meteorites provides a minimum crustal abundance and is equivalent to 50-250 mbar of CO sub(2) being trapped in the uppermost 200-1000 m of the martian crust. Large fractionations in d super(18)O between igneous silicate in the meteorites and the secondary minerals (,30ppt) require formation of the latter below temperatures at which silicate-carbonate equilibration could have taken place (400C) and have been taken to suggest low temperatures (e.g. ,150C) of precipitation from a hydrous fluid.
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