23 research outputs found

    A chemical survey of exoplanets with ARIEL

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    Thousands of exoplanets have now been discovered with a huge range of masses, sizes and orbits: from rocky Earth-like planets to large gas giants grazing the surface of their host star. However, the essential nature of these exoplanets remains largely mysterious: there is no known, discernible pattern linking the presence, size, or orbital parameters of a planet to the nature of its parent star. We have little idea whether the chemistry of a planet is linked to its formation environment, or whether the type of host star drives the physics and chemistry of the planet’s birth, and evolution. ARIEL was conceived to observe a large number (~1000) of transiting planets for statistical understanding, including gas giants, Neptunes, super-Earths and Earth-size planets around a range of host star types using transit spectroscopy in the 1.25–7.8 ÎŒm spectral range and multiple narrow-band photometry in the optical. ARIEL will focus on warm and hot planets to take advantage of their well-mixed atmospheres which should show minimal condensation and sequestration of high-Z materials compared to their colder Solar System siblings. Said warm and hot atmospheres are expected to be more representative of the planetary bulk composition. Observations of these warm/hot exoplanets, and in particular of their elemental composition (especially C, O, N, S, Si), will allow the understanding of the early stages of planetary and atmospheric formation during the nebular phase and the following few million years. ARIEL will thus provide a representative picture of the chemical nature of the exoplanets and relate this directly to the type and chemical environment of the host star. ARIEL is designed as a dedicated survey mission for combined-light spectroscopy, capable of observing a large and well-defined planet sample within its 4-year mission lifetime. Transit, eclipse and phase-curve spectroscopy methods, whereby the signal from the star and planet are differentiated using knowledge of the planetary ephemerides, allow us to measure atmospheric signals from the planet at levels of 10–100 part per million (ppm) relative to the star and, given the bright nature of targets, also allows more sophisticated techniques, such as eclipse mapping, to give a deeper insight into the nature of the atmosphere. These types of observations require a stable payload and satellite platform with broad, instantaneous wavelength coverage to detect many molecular species, probe the thermal structure, identify clouds and monitor the stellar activity. The wavelength range proposed covers all the expected major atmospheric gases from e.g. H2O, CO2, CH4 NH3, HCN, H2S through to the more exotic metallic compounds, such as TiO, VO, and condensed species. Simulations of ARIEL performance in conducting exoplanet surveys have been performed – using conservative estimates of mission performance and a full model of all significant noise sources in the measurement – using a list of potential ARIEL targets that incorporates the latest available exoplanet statistics. The conclusion at the end of the Phase A study, is that ARIEL – in line with the stated mission objectives – will be able to observe about 1000 exoplanets depending on the details of the adopted survey strategy, thus confirming the feasibility of the main science objectives.Peer reviewedFinal Published versio

    Green Edge ice camp campaigns : understanding the processes controlling the under-ice Arctic phytoplankton spring bloom

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    The Green Edge initiative was developed to investigate the processes controlling the primary productivity and fate of organic matter produced during the Arctic phytoplankton spring bloom (PSB) and to determine its role in the ecosystem. Two field campaigns were conducted in 2015 and 2016 at an ice camp located on landfast sea ice southeast of Qikiqtarjuaq Island in Baffin Bay (67.4797∘ N, 63.7895∘ W). During both expeditions, a large suite of physical, chemical and biological variables was measured beneath a consolidated sea-ice cover from the surface to the bottom (at 360 m depth) to better understand the factors driving the PSB. Key variables, such as conservative temperature, absolute salinity, radiance, irradiance, nutrient concentrations, chlorophyll a concentration, bacteria, phytoplankton and zooplankton abundance and taxonomy, and carbon stocks and fluxes were routinely measured at the ice camp. Meteorological and snow-relevant variables were also monitored. Here, we present the results of a joint effort to tidy and standardize the collected datasets, which will facilitate their reuse in other Arctic studies

    Prise en charge des Témoins de Jéhovah lors des interventions chirurgicales à haut risque hémorragique

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    Les TĂ©moins de JĂ©hovah refusent la transfusion de produits sanguins labiles. Lorsqu’une procĂ©dure chirurgicale Ă  risque de saignement est nĂ©cessaire, il faut mettre en place prĂ©cocement des stratĂ©gies d’épargne sanguine. Il s’agit d’un travail d’équipe regroupant le mĂ©decin anesthĂ©siste-rĂ©animateur, le mĂ©decin intensiviste, le chirurgien et le mĂ©decin gĂ©nĂ©raliste. Ces stratĂ©gies mĂ©dicamenteuses et non-mĂ©dicamenteuses doivent ĂȘtre mises en place en pĂ©riode prĂ©opĂ©ratoire et poursuivies tout au long de la prise en charge mĂ©dicochirurgicale. Cette prise en charge doit respecter un cadre lĂ©gal bien dĂ©fini. Cet article propose des orientations de prise en charge afin d’aider les Ă©quipes mĂ©dicales

    Compressibility and Hydraulic Conductivity of Reconstituted Soil-Compost Mixtures for Urban Horticulture

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    International audienceThe aim of our study was to evaluate the efficiency of compost application to reduce the soil susceptibility to compaction and to improve the circulation of water. To this purpose, we studied several soil/compost mixtures differing by compost type, compost particle size, and amount of compost introduced, after an accelerated ageing. Density, porosity and saturated hydraulic conductivity were measured before and after a compaction of 100 kPa which is equivalent to the weight of a car. The main factor inducing difference between the mixtures was the introduced amount of compost: the mixtures with 40% v/v of compost were less dense compared with 20% v/v and the control soil, before and after compression. Ageing did not affect the compression results. The study suggests that the most promising results occurred in the treatment with the largest proportion of compost (40% v/v). The benefits of compost on the soil properties were relatively small with the 20% v/v mixture. The particle size of the compost had a relatively small effect on properties and was apparent only for the 40% v/v mixtures. These results suggest compost addition to soil at 40% may improve physical properties in urban soils. The use of stable compost is likely to provide long term positive effect on the soil agronomic properties and benefit plant growth

    Does the perioperative analgesic/anesthetic regimen influence the prevalence of long-term chronic pain after mastectomy?

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    STUDY OBJECTIVE: To investigate if the anesthetic/analgesic regimen is associated with the risk of reporting long-term chronic postmastectomy pain (CPMP). DESIGN: Cross-sectional survey SETTING: Academic hospital PATIENTS: A total of 267 women having undergone mastectomy with axillary lymph node dissection between 2003 and 2008 INTERVENTIONS: All patients were contacted between October and December 2012, with a questionnaire asking for persistent pain after surgery and its characteristics. MEASUREMENTS: Besides demographical data, tumor characteristics, and adjuvant treatment, we recorded type and doses of intraoperative anesthetics/analgesics (sufentanil, ketamine, clonidine, nonsteroidal anti-inflammatory drugs, MgSO4, propofol, or halogenated agents). RESULTS: Of the 128 patients returning analyzable questionnaires, 43.8% reported chronic pain (48.2% with neuropathic characteristics). Multivariate logistic/linear regression model showed 4 factors independently associated with persistent pain: recall of preoperative pain (odds ratio [OR], 1.27; 95% confidence interval [CI], 1.09-1.48), chemotherapy (OR, 1.32; 95% CI, 1.13-1.55), need for strong opioids in postanesthesia care unit (OR, 1.30; 95% CI, 1.11-1.53), and halogenated agent anesthesia (OR, 0.81; 95% CI, 0.70-0.95). CONCLUSION: In conclusion, our study confirms the high prevalence of CPMP, 4 to 9 years after surgery. Recall of preoperative pain, chemotherapy, and need for strong opioids in the postanesthesia care unit were all associated with the presence of chronic pain. Of the intraoperative analgesics/anesthetics studied, only use of halogenated agents was associated with a lower prevalence of CPMP

    Diagnostic accuracy of a rapid RT-PCR assay for point-of-care detection of influenza A/B virus at emergency department admission: A prospective evaluation during the 2017/2018 influenza season

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    International audienceSTUDY OBJECTIVE: To investigate the performance of a rapid RT-PCR assay to detect influenza A/B at emergency department admission.METHODS: This single-center prospective study recruited adult patients attending the emergency department for influenza-like illness. Triage nurses performed nasopharyngeal swab samples and ran rapid RT-PCR assays using a dedicated device (cobas Liat, Roche Diagnostics, Meylan, France) located at triage. The same swab sample was also analyzed in the department of virology using conventional RT-PCR techniques. Patients were included 24 hours-a-day, 7 days-a-week. The primary outcome was the diagnostic accuracy of the rapid RT-PCR assay performed at triage.RESULTS: A total of 187 patients were included over 11 days in January 2018. Median age was 70 years (interquartile range 44 to 84) and 95 (51%) were male. Nine (5%) assays had to be repeated due to failure of the first assay. The sensitivity of the rapid RT-PCR assay performed at triage was 0.98 (95% confidence interval (CI): 0.91-1.00) and the specificity was 0.99 (95% CI: 0.94-1.00). A total of 92 (49%) assays were performed at night-time or during the weekend. The median time from patient entry to rapid RT-PCR assay results was 46 [interquartile range 36-55] minutes.CONCLUSION: Rapid RT-PCR assay performed by nurses at triage to detect influenza A/B is feasible and highly accurate

    TG4010 immunotherapy and first-line chemotherapy for advanced non-small-cell lung cancer (TIME): results from the phase 2b part of a randomised, double-blind, placebo-controlled, phase 2b/3 trial.

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    Background: MUC1 is a tumour-associated antigen expressed by many solid tumours, including non-small-cell lung cancer. TG4010 is a modified vaccinia Ankara expressing MUC1 and interleukin 2. In a previous study, TG4010 combined with chemotherapy showed activity in non-small-cell lung cancer and the baseline value of CD16, CD56, CD69 triple-positive activated lymphocytes (TrPAL) was shown to be potentially predictive of TG4010 efficacy. In this phase 2b part of the phase 2b/3 TIME trial, we further assess TG4010 in combination with first-line chemotherapy and use of the TrPAL biomarker in this setting.Methods: In this phase 2b part of a randomised, double-blind, placebo-controlled, phase 2b/3 trial, we recruited previously untreated patients aged 18 years or older with stage IV non-small-cell lung cancer without a known activating EGFR mutation and with MUC1 expression in at least 50% of tumoural cells. Patients were randomly allocated (1:1) by an external service provider to subcutaneous injections of 108 plaque-forming units of TG4010 or placebo from the beginning of chemotherapy every week for 6 weeks and then every 3 weeks up to progression, discontinuation for any reason, or toxic effects, stratified according to baseline value of TrPAL (? or > the upper limit of normal [ULN]) and, in addition, a dynamic minimisation procedure was used, taking into account chemotherapy regimen, histology, addition or not of bevacizumab, performance status, and centre. Patients, site staff, monitors, the study funder, data managers, and the statistician were masked to treatment identity. The primary endpoint was progression-free survival, assessed every 6 weeks, to validate the predictive value of the TrPAL biomarker. If patients with TrPAL values of less than or equal to the ULN had a Bayesian probability of more than 95% that the true hazard ratio (HR) for progression-free survival was less than 1, and if those with TrPAL values of greater than the ULN had a probability of more than 80% that the true HR for progression-free survival was more than 1, the TrPAL biomarker would be validated. We did primary analyses in the intention-to-treat population and safety analyses in those who had received at least one dose of study drug and had at least one valid post-baseline safety assessment. Monitors, site staff, and patients are still masked to treatment assignment. This trial is registered with ClinicalTrials.gov, number NCT01383148.Findings: Between April 10, 2012, and Sept 12, 2014, we randomly allocated 222 patients (TG4010 and chemotherapy 111 [50%]; placebo and chemotherapy 111 [50%]). In the whole population, median progression-free survival was 5·9 months (95% CI 5·4–6·7) in the TG4010 group and 5·1 months (4·2–5·9) in the placebo group (HR 0·74 [95% CI 0·55–0·98]; one-sided p=0·019). In patients with TrPAL values of less than or equal to the ULN, the HR for progression-free survival was 0·75 (0·54–1·03); the posterior probability of the HR being less than 1 was 98·4%, and thus the primary endpoint was met. In patients with TrPAL values of greater than the ULN, the HR for progression-free survival was 0·77 (0·42–1·40); the posterior probability of the HR being greater than 1 was 31·3%, and the primary endpoint was not met. We noted grade 1–2 injection-site reactions in 36 (33%) of 110 patients in the TG4010 group versus four (4%) of 107 patients in the placebo group. We noted no grade 3 or 4 nor serious adverse events deemed to be related to TG4010 only. Four (4%) patients presented grade 3 or 4 adverse events related to TG4010 and other study treatments (chemotherapy or bevacizumab) versus 11 (10%) in the placebo group. No serious adverse event was related to the combination of TG4010 with other study treatments. The most frequent severe adverse events were neutropenia (grade 3 29 [26%], grade 4 13 [12%] in the TG4010 group vs grade 3 22 [21%], grade 4 11 [10%] in the placebo group), anaemia (grade 3 12 [11%] vs grade 3 16 [15%]), and fatigue (grade 3 12 [11%], grade 5 one [1%] vs grade 3 13 [12%]; no grade 4 events).Interpretation: TG4010 plus chemotherapy seems to improve progression-free survival relative to placebo plus chemotherapy. These data support the clinical value of the TrPAL biomarker in this clinical setting; because the primary endpoint was met, the trial is to continue into the phase 3 part.Funding: Transgene, AvancĂ©es Diagnostiques pour de Nouvelles Approches ThĂ©rapeutiques (ADNA), and OSEO
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