Mineralogical Limitations for X-Ray Tomography of Crystalline Cumulate Rocks

The use of x-ray computed tomography (XRCT) on igneous rocks enables the visualisation and quantification of the 3D texture of the rock and of the crystal population as opposed to a more traditional 2D vision using thin sections and 3D stereological conversions. Although still in its infancy, the application of XRCT on igneous rocks provides a 3D map of the distribution of each mineral phase, the overall dimensional metrology of crystals (size, area volume, shape, orientation and geometry) and potentially their crystallographic orientation. The precision of crystal size distributions (CSD), which are often used for describing rocks and understanding igneous processes, is enhanced by the use of the 3D analysis of crystal size. XRCT shows promising results when applied to volcanic rocks but only limited applications with intrusive igneous rocks In this study, we compare the dimensional metrology of crystals in 2D and in 3D of a Tugtutoq peridotite sample using a thin section and 3D tomography data to investigate how different the 3D data is from the 2D to test the utility of using XRCT on a dense cumulate. The tomography data is processed in four steps: i) post-processing which includes filtering noise and correcting artefacts linked to the XRCT acquisition; ii) segmentation of the cumulus phase in the sample (in this case olivine); iii) separation of the segmented olivine into realistic and discrete crystals; and iv) the extraction of the data from the 3D-separated olivine crystals (size, location and distribution in the sample, shape, orientation, …). The results of the tomography scan of the peridotite sample are close to the thin section data but the error associated with the tomography data is difficult to quantify. That error is likely high due to the low contrast in attenuation coefficients between the crystal populations – linked to the similar densities of the mineral phases in the sample – and the close proximity and extensive contact between the olivine crystals. When applied to cumulate rocks, the method cannot be automated to produce reproducible and objective results, but we suggest the application of this method for processing tomography data with either volcanic rocks or cumulates solidified from a more permeable mush, where there is minimal contact between the crystals of interest and the density contrast between phenocrysts and groundmass is high

The permeability of magma mush

Models for the evolution of magma mush zones are of fundamental importance for understanding magma storage, differentiation in the crust, and melt extraction processes that prime eruptions. Mush mobilisation and melt segregation are predominant mechanisms that control mush evolution yet are to date still insufficiently understood and models for these are poorly constrained. These models are underpinned by calculations of the permeability of the evolving crystal frameworks in the mush, which controls the rate of melt movement relative to crystals. To date, no mush permeability model accounts for the shape of the crystals that form the crystal-framework in the mush. Herein, we assume that mush crystals are approximately cuboidal, and using that geometric approximation, we present new models for the permeability of mush in which crystal shape parameters are a key input. First, we present an extension of the Kozeny-Carman permeability law specifically for crystal packs at their maximum packing, for which the axis lengths of the crystals are the primary input. Second, we present a model for the evolution of magma mush permeability that is valid from maximum packing down to low melt fractions, ideal for simulating permeability as mush crystalises. In all cases we use a combination of numerical approaches to generate packs of cuboids for analysis, and experimental approaches to create digital 3D scans of anisotropic crystal shapes as an analogue for crystal mush. Using a combination of Avizo 3D image analysis, and a lattice-Boltzmann simulation technique, we constrain the permeability of both the numerical and experimental samples; these data then validate our models across a wide range of parameter space applicable to real magma mush. Furthermore, we propose and validate innovative solutions for permeability that can be found using only 2D data (for example, using a thin section scan), which is useful for common situations where full 3D information may not be available for analysis. In general, our results show that if we consider melt percolation in magma mush akin to fluid flow through porous media, the complexity and anisotropy are well represented by the specific surface area of the crystals. Knowledge of the crystal shape and size are essential variables in our proposed permeability model, unless the mush displays overgrowth textures at low melt fraction, in which case the effect of shape becomes less important. Our results have key implications for melt extraction timescales and cumulate textures as well as for crustal melt segregation processes and reactive flow on the scale of mush reservoirs

Frequently asked questions regarding SARS-CoV-2 in cancer patients—recommendations for clinicians caring for patients with malignant diseases

Since early 2020, the SARS-CoV-2 pandemic has a massive impact on health care systems worldwide. Patients with malignant diseases are assumed to be at increased risk for a worse outcome of SARS-CoV-2 infection, and therefore, guidance regarding prevention and management of the infection as well as safe administration of cancer-therapy is required. Here, we provide recommendations for the management of patients with malignant disease in the times of COVID-19. These recommendations were prepared by an international panel of experts and then consented by the EHA Scientific Working Group on Infection in Hematology. The primary aim is to enable clinicians to provide optimal cancer care as safely as possible, since the most important protection for patients with malignant disease is the best-possible control of the underlying disease.Open access funding provided by Projekt DEA

Circulating microparticles from Crohn's disease patients cause endothelial and vascular dysfunctions

BACKGROUND: Microparticles (MPs) are small vesicles released during cell activation or apoptosis. They are involved in coagulation, inflammation and vascular dysfunction in several diseases. We characterized circulating MPs from Crohn's Disease (CD) patients and evaluated their effects on endothelial function and vascular reactivity after in vivo injection into mice. METHODS: Circulating MPs and their cellular origins were examined by flow cytometry from blood samples from healthy subjects (HS) and inactive or active CD patients. MPs were intravenously injected into mice. After 24 hours, endothelial function and vascular reactivity were assessed. RESULTS: Circulating MP levels did not differ between HS and inactive CD patients except for an increase in leukocyte-derived MPs in CD. Active CD patients compared to HS displayed increased total circulating MPs, pro-coagulant MPs and those from platelets, endothelium, erythrocytes, leukocytes, activated leukocytes and activated platelets. A significant correlation was found between total levels of MPs, those from platelets and endothelial cells, and the Harvey-Bradshaw clinical activity index. MPs from CD, but not from HS, impaired endothelium-dependent relaxation in mice aorta and flow-induced dilation in mice small mesenteric arteries, MPs from inactive CD patients being more effective than those from active patients. CDMPs induced vascular hypo-reactivity in aorta that was prevented by a nitric oxide (NO)-synthase inhibitor, and was associated with a subtle alteration of the balance between NO, reactive oxygen species and the release of COX metabolites. CONCLUSIONS: We provide evidence that MPs from CD patients significantly alter endothelial and vascular function and therefore, may play a role in CD pathophysiology, at least by contributing to uncontrolled vascular-dependent intestinal damage

Urban Climate, Human behavior & Energy consumption: from LCZ mapping to simulation and urban planning (the MapUCE project)

International audienceThe MApUCE project aims to integrate in urban policies and most relevant legal documents quantitative data from urban microclimate, climate and energy.The primary objective of this project is to obtain climate and energy quantitative data from numerical simulations, focusing on urban microclimate and building energy consumption in the residential and service sectors, which represents in France 41% of the final energy consumption. Both aspects are coupled as building energy consumption is highly meteorologically dependent (e.g. domestic heating, air-conditioning) and heat waste impact the Urban Heat Island. We propose to develop, using national databases, a generic and automated method for generating Local Climate Zones (LCZ) for all cities in France, including the urban architectural, geographical and sociological parameters necessary for energy and microclimate simulations.As will be presented, previous projects on adaptation of cities to climate change have shown that human behavior is a very potent level to address energy consumption reduction, as much as urban forms or architectural technologies. Therefore, in order to further refine the coupled urban climate and energy consumption calculations, we will develop within TEB (and its Building Energy Module) a model of energy consumer behavior.The second objective of the project is to propose a methodology to integrate quantitative data in urban policies. Lawyers analyze the potential levers in legal and planning documents. A few “best cases” are also studied, in order to evaluate their performances. Finally, based on urban planning agencies requirements, we will define vectors to include quantified energy-climate data to legal urban planning documents. These vectors have to be understandable by urban planners and contain the relevant information.To meet these challenges, the project is organized around strongly interdisciplinary partners in the following fields: law, urban climate, building energetics, architecture, sociology, geography and meteorology, as well as the national federation of urban planning agencies.In terms of results, the cross-analysis of input urban parameters and urban micro-climate-energy simulated data will be available on-line as standardized maps for each of the studied cities. The urban parameter production tool as well as the models will be available as open-source. LCZ and associated urban (and social!) indicators may be integrated within the WUDAPT database

Optimizing Therapy to Prevent Avoidable Hospital Admissions in Multimorbid Older Adults (OPERAM): cluster randomised controlled trial.

OBJECTIVE To examine the effect of optimising drug treatment on drug related hospital admissions in older adults with multimorbidity and polypharmacy admitted to hospital. DESIGN Cluster randomised controlled trial. SETTING 110 clusters of inpatient wards within university based hospitals in four European countries (Switzerland, Netherlands, Belgium, and Republic of Ireland) defined by attending hospital doctors. PARTICIPANTS 2008 older adults (≥70 years) with multimorbidity (≥3 chronic conditions) and polypharmacy (≥5 drugs used long term). INTERVENTION Clinical staff clusters were randomised to usual care or a structured pharmacotherapy optimisation intervention performed at the individual level jointly by a doctor and a pharmacist, with the support of a clinical decision software system deploying the screening tool of older person's prescriptions and screening tool to alert to the right treatment (STOPP/START) criteria to identify potentially inappropriate prescribing. MAIN OUTCOME MEASURE Primary outcome was first drug related hospital admission within 12 months. RESULTS 2008 older adults (median nine drugs) were randomised and enrolled in 54 intervention clusters (963 participants) and 56 control clusters (1045 participants) receiving usual care. In the intervention arm, 86.1% of participants (n=789) had inappropriate prescribing, with a mean of 2.75 (SD 2.24) STOPP/START recommendations for each participant. 62.2% (n=491) had ≥1 recommendation successfully implemented at two months, predominantly discontinuation of potentially inappropriate drugs. In the intervention group, 211 participants (21.9%) experienced a first drug related hospital admission compared with 234 (22.4%) in the control group. In the intention-to-treat analysis censored for death as competing event (n=375, 18.7%), the hazard ratio for first drug related hospital admission was 0.95 (95% confidence interval 0.77 to 1.17). In the per protocol analysis, the hazard ratio for a drug related hospital admission was 0.91 (0.69 to 1.19). The hazard ratio for first fall was 0.96 (0.79 to 1.15; 237 v 263 first falls) and for death was 0.90 (0.71 to 1.13; 172 v 203 deaths). CONCLUSIONS Inappropriate prescribing was common in older adults with multimorbidity and polypharmacy admitted to hospital and was reduced through an intervention to optimise pharmacotherapy, but without effect on drug related hospital admissions. Additional efforts are needed to identify pharmacotherapy optimisation interventions that reduce inappropriate prescribing and improve patient outcomes. TRIAL REGISTRATION ClinicalTrials.gov NCT02986425

Eradication de Helicobacter pylori dans le traitement de l'ulcère gastroduodénal

RENNES1-BU Santé (352382103) / SudocSudocFranceF

Earliest case of Candida auris infection imported in 2007 in Europe from India prior to the 2009 description in Japan

International audienceCandida auris is an emerging pathogen frequently associated with multidrug resistance and involved in many worldwide outbreaks. We here report the first European imported case in France due to isolate belonging of the South Indian clade I and the importance of prevention measure to avoid fungal spreading

FlexGD : A Flexible Force-directed Model for Graph Drawing, Inria

We propose FlexGD, a force-directed algorithm for straightline undirected graph drawing. The algorithm strives to draw graph layouts encompassing from uniform vertex distribution to extreme structure abstraction. It is flexible for it is parameterized so that the emphasis can be put on either of the two drawing criteria. The parameter determines how much the edges are shorter than the average distance between vertices. Extending the clustering property of the LinLog model, FlexGD is efficient for cluster visualization in an adjustable level. The energy function of FlexGD is minimized through a multilevel approach, particularly designed to work in contexts where edge length distribution is not uniform. Applying FlexGD on several real datasets, we illustrate both the good quality of the layout on various topologies, and the ability of the algorithm to meet the addressed drawing criteria

Typing Candida Species Using Microsatellite Length Polymorphism and Multilocus Sequence Typing

International audienceTo gain more insight into the epidemiological relationships between isolates of Candida spp. obtained from various origins, several molecular typing techniques have been developed. Two methods have emerged in the 2000s as soon as enough knowledge of the Candida spp. genomes was available to choose adequate loci and primers, namely microsatellite length polymorphism (MLP) and multilocus sequence typing (MLST). To contrast with previous PCR-based methods, specific amplifications with stringent conditions easily reproducible are the basis of MLP and MLST. MLST relies on Sanger sequencing to detect single-nucleotide polymorphisms within housekeeping genes. MLP needs a first in silico step to select tandemly repeated stretches of two to five nucleotides. One of the two primers used to amplify a microsatellite locus is labeled and fragment sizing is automatically performed using high-resolution electrophoresis platforms. MLST provides results easily comparable between laboratories and active MLST schemes are publicly available for the main Candida species. For comparative studies, MLP needs standards to compensate for the electrophoretic variations depending on the platforms used. Both methods can help us gain insight into the genetic relatedness of fungal isolates, both with advantages and drawbacks, and the choice of one method rather than the other depends on the task in question