The role of the antigorite + brucite to olivine reaction in subducted serpentinites (Zermatt, Switzerland)

Metamorphic olivine formed by the reaction of antigorite + brucite is widespread in serpentinites that crop out in glacier-polished outcrops at the Unterer Theodulglacier, Zermatt. Olivine overgrows a relic magnetite mesh texture formed during ocean floor serpentinization. Serpentinization is associated with rodingitisation of mafic dykes. Metamorphic olivine coexists with magnetite, shows high Mg# of 94–97 and low trace element contents. A notable exception is 4 µg/g Boron (> 10 times primitive mantle), introduced during seafloor alteration and retained in metamorphic olivine. Olivine incorporated 100–140 µg/g H2O in Si-vacancies, providing evidence for low SiO2-activity imposed by brucite during olivine growth. No signs for hydrogen loss or major and minor element diffusional equilibration are observed. The occurrence of olivine in patches within the serpentinite mimics the former heterogeneous distribution of brucite, whereas the network of olivine-bearing veins and shear zones document the pathways of the escaping fluid produced by the olivine forming reaction. Relic Cr-spinels have a high Cr# of 0.5 and the serpentinites display little or no clinopyroxene, indicating that they derive from hydrated harzburgitic mantle that underwent significant melt depletion. The enrichment of Mg and depletion of Si results in the formation of brucite during seafloor alteration, a pre-requisite for later subduction-related olivine formation and fluid liberation. The comparison of calculated bulk rock brucite contents in the Zermatt-Saas with average IODP serpentinites suggests a large variation in fluid release during olivine formation. Between 3.4 and 7.2 wt% H2O is released depending on the magnetite content in fully serpentinized harzburgites (average oceanic serpentinites). Thermodynamic modelling indicates that the fluid release in Zermatt occurred between 480 °C and 550 °C at 2–2.5 GPa with the Mg# of olivine varying from 68 to 95. However, the majority of the fluid released from this reaction was produced within a narrow temperature field of < 30 °C, at higher pressures 2.5 GPa and temperatures 550–600 °C than commonly thought. Fluids derived from the antigorite + brucite reaction might thus trigger eclogite facies equilibration in associated metabasalts, meta-gabbros, meta-rodingites and meta-sediments in the area. This focused fluid release has the potential to trigger intermediate depths earthquakes at 60–80 km in subducted oceanic lithosphere. © 2020, The Author(s).ISSN:1661-8734ISSN:1661-872

Competition between Bactericidal/Permeability-Increasing Protein and Lipopolysaccharide-Binding Protein for Lipopolysaccharide Binding to Monocytes

The bactericidal/permeability-increasing protein (BPI) inhibits the lipopolysaccharide (LPS)mediated activation of monocytes. Due to its inhibitory activity for various LPS, BPI has therapeutic potential in endotoxic shock. To be efficient in vivo, BPI should overcome the action of LPS-binding protein (LBP), a serum molecule that increases the expression of LPS-inducible genes via CD 14 of monocytes. rBPI23, a recombinant fragment of BPI, prevented in a dose-dependent manner the binding and the internalization of LPS mediated by LBP. Consequently, rBPI23 also inhibited LPS-induced tumor necrosis factor (TNFα) synthesis from monocytes. LPS- and LBP-mediated activation of monocytes was totally inhibited when LPS was preincubated with rBPI23. Adding rBPI23 at the same time as LBP resulted in an important but partial inhibition of TNFα release, but this inhibition vanished with delaying the time of addition of rBPI23. These studies suggest that the inhibitory activity of BPI is related to its ability to compete with LBP for LP

On the distortion of twin building lattices

We show that twin building lattices are undistorted in their ambient group; equivalently, the orbit map of the lattice to the product of the associated twin buildings is a quasi-isometric embedding. As a consequence, we provide an estimate of the quasi-flat rank of these lattices, which implies that there are infinitely many quasi-isometry classes of finitely presented simple groups. In an appendix, we describe how non-distortion of lattices is related to the integrability of the structural cocycle

Sentencing as craftwork and the binary epistemologies of the discretionary decision process

This article contends that it is time to take a critical look at a series of binary categories which have dominated the scholarly and reform epistemologies of the sentencing decision process. These binaries are: rules versus discretion; reason versus emotion; offence versus offender; normative principles versus incoherence; aggravating versus mitigating factors; and aggregate/tariff consistency versus individualized sentencing. These binaries underpin both the 'legal-rational' tradition (by which I mean a view of discretion as inherently suspect, a preference for the use of philosophy of punishment justifications and an explanation of the decision process through factors or variables), and also the more recent rise of the 'new penology'. Both approaches tend to rely on 'top-down' assumptions of change, which pay limited attention to the agency of penal workers. The article seeks to develop a conception of sentencing craftwork as a social and interpretive process.1 In so doing, it applies and develops a number of Kritzer's observations (in this issue) about craftwork to sentencing. These craftwork observations are: problem solving (applied to the rules - discretion and reason - emotion dichotomies); skills and techniques (normative penal principles and the use of cognitive analytical assumptions); consistency (tariff versus individualized sentencing); clientele (applied to account giving and the reality of decision making versus expression). By conceiving of sentencing as craftwork, the binary epistemologies of the sentencing decision process, which have dominated (and limited) the scholarly and policy sentencing imaginations, are revealed as dynamic, contingent, and synergistic. However, this is not to say that such binaries are no more than empty rhetoric concealing the reality of the decision process. Rather, these binaries serve as crucial legitimating reference points in the vocabulary of sentencing account giving

Grain scale processes recorded by oxygen isotopes in olivine-hosted melt inclusions from two MORB samples

International audienceAlthough olivine-hosted melt inclusions from mid ocean ridge basalts (MORB) are commonly used as a proxy formantle composition, these melt inclusions generally show larger elemental and isotopic compositional variationthan their host lavas and the origin of these heterogeneities remains disputed. Here we present oxygen isotopedata from melt inclusions hosted in olivine from two samples from the Mid-Atlantic ridge. Melt inclusions fromdifferent crystals within the same sample show>2.5‰ δ18O variation within each sample, which is nearly eighttimes the analytical error of 0.3‰ (2 standard deviations) and five times the δ18O range in unaltered MORB.Measured δ18O in melt inclusions do not correlate with common magmatic tracers, and δ18O measured in thehost olivines suggest a maximum of 1‰ δ18O source heterogeneity. Less than half of the melt inclusions fromeach sample are in equilibrium with their host crystals; the remaining melt inclusions have either lower or higherolivine-melt oxygen isotope partition coefficients compared to the theoretical equilibrium values. Here wediscuss several potential processes that could contribute to these observations, but none satisfactorily explain theolivine-melt inclusion oxygen disequilibrium that we observe in these samples. Nevertheless, it seems clear thatthe variability of δ18O in melt inclusion from two MORB samples do not record only common magmatic process(es), but rather a localized grain scale process. Any δ18O variation in melt inclusions should thus be interpretedwith caution

Canakinumab in patients with COVID-19 and type 2 diabetes - A multicentre, randomised, double-blind, placebo-controlled trial

BACKGROUND: Patients with type 2 diabetes and obesity have chronic activation of the innate immune system possibly contributing to the higher risk of hyperinflammatory response to SARS-CoV2 and severe COVID-19 observed in this population. We tested whether interleukin-1β (IL-1β) blockade using canakinumab improves clinical outcome. METHODS: CanCovDia was a multicenter, randomised, double-blind, placebo-controlled trial to assess the efficacy of canakinumab plus standard-of-care compared with placebo plus standard-of-care in patients with type 2 diabetes and a BMI > 25 kg/m$^{2}$ hospitalised with SARS-CoV2 infection in seven tertiary-hospitals in Switzerland. Patients were randomly assigned 1:1 to a single intravenous dose of canakinumab (body weight adapted dose of 450-750 mg) or placebo. Canakinumab and placebo were compared based on an unmatched win-ratio approach based on length of survival, ventilation, ICU stay and hospitalization at day 29. This study is registered with ClinicalTrials.gov, NCT04510493. FINDINGS: Between October 17, 2020, and May 12, 2021, 116 patients were randomly assigned with 58 in each group. One participant dropped out in each group for the primary analysis. At the time of randomization, 85 patients (74·6 %) were treated with dexamethasone. The win-ratio of canakinumab vs placebo was 1·08 (95 % CI 0·69-1·69; p = 0·72). During four weeks, in the canakinumab vs placebo group 4 (7·0%) vs 7 (12·3%) participants died, 11 (20·0 %) vs 16 (28·1%) patients were on ICU, 12 (23·5 %) vs 11 (21·6%) were hospitalised for more than 3 weeks, respectively. Median ventilation time at four weeks in the canakinumab vs placebo group was 10 [IQR 6.0, 16.5] and 16 days [IQR 14.0, 23.0], respectively. There was no statistically significant difference in HbA1c after four weeks despite a lower number of anti-diabetes drug administered in patients treated with canakinumab. Finally, high-sensitive CRP and IL-6 was lowered by canakinumab. Serious adverse events were reported in 13 patients (11·4%) in each group. INTERPRETATION: In patients with type 2 diabetes who were hospitalised with COVID-19, treatment with canakinumab in addition to standard-of-care did not result in a statistically significant improvement of the primary composite outcome. Patients treated with canakinumab required significantly less anti-diabetes drugs to achieve similar glycaemic control. Canakinumab was associated with a prolonged reduction of systemic inflammation. FUNDING: Swiss National Science Foundation grant #198415 and University of Basel. Novartis supplied study medication

Mitochondrial Fusion Is Increased by the Nuclear Coactivator PGC-1β

Background There is no evidence to date on whether transcriptional regulators are able to shift the balance between mitochondrial fusion and fission events through selective control of gene expression. Methodology/Principal Findings Here, we demonstrate that reduced mitochondrial size observed in knock-out mice for the transcriptional regulator PGC-1β is associated with a selective reduction in Mitofusin 2 (Mfn2) expression, a mitochondrial fusion protein. This decrease in Mfn2 is specific since expression of the remaining components of mitochondrial fusion and fission machinery were not affected. Furthermore, PGC-1β increases mitochondrial fusion and elongates mitochondrial tubules. This PGC-1β-induced elongation specifically requires Mfn2 as this process is absent in Mfn2-ablated cells. Finally, we show that PGC-1β increases Mfn2 promoter activity and transcription by coactivating the nuclear receptor Estrogen Related Receptor α (ERRα). Conclusions/Significance Taken together, our data reveal a novel mechanism by which mammalian cells control mitochondrial fusion. In addition, we describe a novel role of PGC-1β in mitochondrial physiology, namely the control of mitochondrial fusion mainly through Mfn2

Benzofuran-fused Phosphole: Synthesis, Electronic, and Electroluminescence Properties

International audienceA synthetic route to novel benzofuran-fused phosphole derivatives 3-5 is described. These compounds showed optical and electrochemical properties that differ from their benzothiophene analog. Preliminary results show that 4 can be used as an emitter in OLEDs, illustrating the potential of these new compounds for opto-electronic applications