Long-term outcome of severe herpes simplex encephalitis: a population-based observational study

Literature review for adult case reports and series of patients undergoing decompressive hemicraniectomy for severe herpes simplex encephalitis. (PDF 57 kb

3D Groundwater flow model at the Upper Rhine Graben scale to delineate preferential target areas for geothermal projects

International audienceAny deep unconventional geothermal project remains risky because of the uncertainty regarding the presence of the geothermal resource at depth and the drilling costs increasing accordingly. That's why this resource must be located as precisely as possible to increase the chances of successful projects and their economic viability. To minimize the risk, as much information as possible should be gathered prior to any drilling. Usually, the position of the exploration wells of geothermal energy systems is chosen based on structural geology observations, geophysics measurements and geochemical analyses. Confronting these observations to results from additional disciplines should bring more objectivity in locating the region to explore and where to implant the geothermal system. The Upper Rhine Graben (URG) is a tectonically active rift system that corresponds to one branch of the European Cenozoic Rift System where the basin hosts a significant potential for geothermal energy. The large fault network inherited from a complex tectonic history and settled under the sedimentary deposits hosts fluid circulation patterns. Geothermal anomalies are strongly influenced by fluid circulations within permeable structures such as fault zones. In order to better predict the location of the geothermal resource, it is necessary to understand how it is influenced by heat transport mechanisms such as groundwater flow. The understanding of fluid circulation in hot fractured media at large scale can help in the identification of preferential zones at a finer scale where additional exploration can be carried out. Numerical simulations is a useful tool to deal with the issue of fluid circulations through large fault networks that enable the uplift of deep and hot fluids. Therefore, we build a numerical model to study groundwater flow at the URG scale (150 x 130km), which aims to delineate preferential zones. The numerical model is based on a hybrid method using a Discrete Fracture Network (DFN) and 3D elements to simulate groundwater flow in the 3D regional fault network and in sedimentary deposits, respectively. Firstly, the geometry of the 3D fracture network and its hydraulic connections with 3D elements (sedimentary cover) is built in accordance with the tectonic history and based on geological and geophysical evidences. Secondly, data from previous studies and site-specific geological knowledge provide information on the fault zones family sets and on respective hydraulic properties. Then, from the simulated 3D groundwater flow model and based on a particle tracking methodology, groundwater flow paths are constructed. The regional groundwater flow paths results are extracted and analysed to delineate preferential zones to explore at finer scale and so to define the potential positions of the exploration wells. This work is conducted in the framework of the IMAGE project (Integrated Methods for Advanced Geothermal Exploration, grant agreement No. 608553), which aims to develop new methods for better siting of exploitation wells

Rare gas systematics on Lucky Strike basalts (37°N, North Atlantic): Evidence for efficient homogenization in a long-lived magma chamber system?

International audienceWe present rare gas data in fresh glasses from the Lucky Strike segment located on the Mid Atlantic Ridge (∼37.3°N), close to the Azores plateau. We analyzed the helium and neon isotopes in 28 samples by melting as well as He‐Ne‐Ar‐Kr‐Xe isotopes in 9 samples by crushing. Samples were collected during the Graviluck06, MOMAR08, and Bathyluck09 cruises over a ridge length of ∼13 km (mean sample spacing of ∼500 m), and at depths ranging from 1550 m to 2174 m. The helium isotopic ratio varies between 84,410 and 88,235 (R/Ra between 8.19 and 8.56). The samples having the “most” primitive helium isotopic ratio are the enriched samples (e.g. high K2O/TiO2) although the difference to the depleted samples is small. It appears that all of our samples derive from the same and well‐homogenized magma chamber. Neon isotopes clearly show the influence of the Azores hotspot, which is not seen with helium because of lower 3He/22Ne in the plume source compared to the MORB source

Adapted numerical modelling strategy developed to support EGS deployment.

International audienceThe exploitation of Enhanced/Engineered Geothermal Systems (EGS), for electricity and/or heat production, is a promising way to increase the amount of renewable energies contribution in the energetic mix in Europe. In regard to the required production characteristics (production temperature and flowrate) for the economical viability of EGS, the favourable targeted geological systems are deep and fractured. In order to reduce the risks and the prohibitive costs linked to the depth of such geothermal systems, numerical modelling is a useful tool to understand such deep fractured systems and to help in the construction and in the management of the deep infrastructures (wells architecture, stimulation of wells, implementation of adapted network of wells). Nevertheless, this forces to a change of paradigm in comparison to « classical » reservoir modelling based on mechanics of continuum media. Indeed 3D Discrete Fracture Network (DFN) approach looks fairly adapted to catch the mechanical and hydraulic phenomena in the fractured rock mass around wells and to understand the global systems in the network of wells. The conceptualisation of the fractured rock mass is a crucial step for such DFN models not only for the geometry but also to constrain the constitutive behaviour of singularities (fault zones, fractures etc.), depending on the tectonic context. We present some results illustrating how DFNs can be used to study the EGS behaviour at several scales

Kallikrein-related peptidase 5 contributes to H3N2 influenza virus infection in human lungs

Hemagglutinin (HA) of influenza virus must be activated by proteolysis before the virus can become infectious. Previous studies indicated that HA cleavage is driven by membrane-bound or extracellular serine proteases in the respiratory tract. However, there is still uncertainty as to which proteases are critical for activating HAs of seasonal influenza A viruses (IAVs) in humans. This study focuses on human KLK1 and KLK5, 2 of the 15 serine proteases known as the kallikrein-related peptidases (KLKs). We find that their mRNA expression in primary human bronchial cells is stimulated by IAV infection. Both enzymes cleaved recombinant HA from several strains of the H1 and/or H3 virus subtype in vitro, but only KLK5 promoted the infectivity of A/Puerto Rico/8/34 (H1N1) and A/Scotland/20/74 (H3N2) virions in MDCK cells. We assessed the ability of treated viruses to initiate influenza in mice. The nasal instillation of only the KLK5-treated virus resulted in weight loss and lethal outcomes. The secretion of this protease in the human lower respiratory tract is enhanced during influenza. Moreover, we show that pretreatment of airway secretions with a KLK5-selective inhibitor significantly reduced the activation of influenza A/Scotland/20/74 virions, providing further evidence of its importance. Differently, increased KLK1 secretion appeared to be associated with the recruitment of inflammatory cells in human airways regardless of the origin of inflammation. Thus, our findings point to the involvement of KLK5 in the proteolytic activation and spread of seasonal influenza viruses in humans

Search for dark matter produced in association with bottom or top quarks in √s = 13 TeV pp collisions with the ATLAS detector

A search for weakly interacting massive particle dark matter produced in association with bottom or top quarks is presented. Final states containing third-generation quarks and miss- ing transverse momentum are considered. The analysis uses 36.1 fb−1 of proton–proton collision data recorded by the ATLAS experiment at √s = 13 TeV in 2015 and 2016. No significant excess of events above the estimated backgrounds is observed. The results are in- terpreted in the framework of simplified models of spin-0 dark-matter mediators. For colour- neutral spin-0 mediators produced in association with top quarks and decaying into a pair of dark-matter particles, mediator masses below 50 GeV are excluded assuming a dark-matter candidate mass of 1 GeV and unitary couplings. For scalar and pseudoscalar mediators produced in association with bottom quarks, the search sets limits on the production cross- section of 300 times the predicted rate for mediators with masses between 10 and 50 GeV and assuming a dark-matter mass of 1 GeV and unitary coupling. Constraints on colour- charged scalar simplified models are also presented. Assuming a dark-matter particle mass of 35 GeV, mediator particles with mass below 1.1 TeV are excluded for couplings yielding a dark-matter relic density consistent with measurements