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RésuméCet article a pour point de départ la querelle épistémologique survenue entre Anthony D. Smith et Jon E. Fox et Cynthia Miller-Idriss concernant les différentes approches du champ d’études du nationalisme. Alors que Fox et Miller-Idriss rejettent la pertinence d'une approche sociohistorique dans l’étude ethnographique du nationalisme, Smith considère l'ethnographie comme une pratique descriptiviste dénuée d'intérêt scientifique qui, de surcroit, fait abstraction des recherches sur la nation conduite au cours des dernières décennies. Afin de dénouer cette impasse, nous proposons une démarche méthodologique visant à concilier ces deux approches par l'entremise du concept de lieu de mémoire. À partir d'une étude de cas, la bataille des Éperons d'or et sa résonance dans les pratiques discursives, nous illustrons comment l'historicité du fait national peut s'avérer essentielle pour comprendre le fonctionnement de la nation au quotidien et nous éclairer sur la manière dont les Flamands se construisent en tant que sujets nationaux.

The COVID-19 pandemic has motivated the development of teleconsultation in anaesthesia. We have conducted a single centre prospective study in patients scheduled for planned orthopaedic surgery during 9 weeks between may and july 2020 to assess its practicability. The quality of the consultation and patients' satisfaction, were evaluated during this period. The teleconsultation was successful in 90% of the patients without the need of attendance to the hospital for assessment before anaesthesia. The process was satisfactory for 97% of these patients. The mean duration was 15 minutes. The support of a third party was required in 46% of patients older than 65 years. The main cause of failure was the poor quality of the connection. Only two patients were cancelled for surgery because they did not understand fasting rule. The teleconsultation is now an integral part of preoperative assessment of patients for anaesthesia with good practicability and reliability.

Resume Le sejour en SSPI est une etape negligee du processus de rehabilitation postoperatoire. La prescription de sortie sur validation de score permet d’en optimiser la duree. Il est possible de court-circuiter la SSPI sous certaines conditions d’autonomie. La SSPI n’est pas uniquement le lieu de surveillance des patients qui viennent d’etre operes. C’est aussi le site de la mise en œuvre de soins de support dont l’initiative peut etre deleguee aux infirmieres et qui se poursuivent ulterieurement. Le sevrage precoce de la ventilation est favorise notamment par le monitorage de la profondeur d’anesthesie et de la curarisation. La reprise de la prise de boisson peut se faire des le sejour en SSPI. Il est egalement possible de quitter la SSPI en deambulant avant de regagner sa chambre d’hospitalisation ce qui facilite la poursuite de la marche en postoperatoire.

Ouverture et action collective, c’est autour de ces deux dimensions que nous avons voulu compléter ce numéro par une série de huit entretiens Il allait de soi de commencer par celui sur Gilles Dostaler, tant son œuvre est empreinte de l’esprit d’ouverture et de progrès social. Internationalement reconnu pour ses travaux sur Keynes et l’histoire de la pensée économique, Gilles Dostaler joua un très grand rôle dans les débats en économie politique au Québec. Grâce au témoignage de Marielle Cau...

01. Le contexte de ce numéro L’histoire des idées est une discipline qui n’a plus le vent en poupe en économie. Suivant une trajectoire typique identifiée par Thomas Kuhn pour d’autres sciences, les économistes tendent à laisser à d’autres le soin de faire l’histoire de leur discipline au fur et à mesure que celle-ci se formalise. C’est un peu comme si l’histoire de la discipline économique n’avait pas d’intérêt au-delà d’une démarche scolastique un peu pédante. Or, les certitudes des néoclas...

The coronavirus disease 2019 (COVID-19) may lead to an acute respiratory distress syndrome by an inappropriate cytokine response and may predispose to a prothrombotic state through multiple pathways. Both can complicate the management of cardiac surgery with cardiopulmonary bypass, which is known to activate the hemostatic system and to exacerbate systemic inflammatory response. Little is known about the impact of cardiac surgery with cardiopulmonary bypass on viral pneumonia, particularly with the new coronavirus. In this article, we describe the case of a diabetic patient with COVID-19 and a concomitant 3-vessel disease with a formal indication for surgical revascularization, who unexpectedly presented with a high heparin resistance during cardiopulmonary bypass. Emphasis is placed on the importance of multidisciplinary team discussions before surgery, on the thorough preoperative assessment, and on the perioperative management, particularly regarding mechanical ventilation and anticoagulation.

International audience; Designing and deploying mobile applications for Edge/Fog environments is challenging. Previous studies have introduced simulation and emulation tools that can help to model new applications but fail to deliver an environment in which a system designer can emulate a realistic deployment of such applications. We propose the Mobile Ad-hoc Computing Framework (MACE) that provides features which facilitate and accelerate the development and testing of Edge/Fog applications. It also provides the nodes with mobility control that can be modelled or triggered by external applications, such as a flight simulator. With the included GUI, the user can plan deployment topologies, observe and interact with the nodes in real-time. To demonstrate its functionalities, two experimental evaluations were performed: one comparing the network emulators and another with an off-the-shelf configuration service running in mobile nodes. Finally, the functionality of controlling mobility via an external application is also demonstrated.

Resume La vasoconstriction pulmonaire hypoxique (VPH) est un mecanisme reflexe unique aux poumons : la baisse de pression alveolaire en oxygene induit une vasoconstriction locale contrairement a ce qui se passe dans les autres tissus. Cela permet une redistribution preferentielle du debit sanguin vers des zones mieux ventilees afin d’optimiser l’hematose. Cette reponse est variable, modulee par des facteurs genetiques (voie du « facteur induit par l’hypoxie », HIF), metaboliques (equilibre acido-basique), pharmacologiques, le statut martial. Les mecanismes cellulaires peuvent se resumer ainsi : la cellule musculaire lisse des arteres pulmonaires resistives joue un role majeur, avec un senseur a l’oxygene (dans les mitochondries), inhibition de canaux K+ specifiques de cette circulation, activation de canaux Ca2+, transduction par la [Ca2+]i et de certaines voies (rho-kinase, HIF, etc.), avec une reponse en contraction, voire en proliferation si le stimulus perdure. La contraction est biphasique, les mecanismes cellulaires etant differents. Sa reversibilite est retardee quand le stimulus est prolonge. En pratique, la VPH est benefique quand le trouble de ventilation est localise, mais peut etre deletere quand l’hypoxie est generalisee (par exemple hypoxie d’altitude) surtout chez les patients ayant une reponse exacerbee (a risque d’œdeme pulmonaire d’altitude). Dans les situations ou la VPH joue un role dans le maintien de l’hematose (en particulier la ventilation unipulmonaire en chirurgie thoracique), il faut la respecter. Les agents d’anesthesie recents n’ont pas d’effets aux doses habituelles. L’alcalose, l’hypothermie et certains vasodilatateurs peuvent l’inhiber. Elle joue un role egalement dans certaines situations : sepsis, cirrhose, maladies pulmonaires hypoxemiantes.

In a fan stage under windmilling conditions, the stator operates under negative incidence, leading to flow separation, which may present an unsteady behaviour due to rotor/stator interactions. An experimental study of the unsteady flow through the fan stage of a bypass turbofan in windmilling is proposed, using hot-wire anemometry. Windmilling conditions are reproduced in a ground engine test bed by blowing a variable mass flow through a bypass turbofan in ambient conditions. Time-averaged profiles of flow coefficient are independent of the mass flow, demonstrating the similarity of velocity triangle. Turbulence intensity profiles reveal that the high levels of turbulence production due to local shear are also independent of the inlet flow. A spectral analysis confirms that the flow is dominated by the blade passing frequency, and that the separated regions downstream of the stator amplify the fluctuations locked to the BPF without adding any new frequency. Phase-locked averaging is used to capture the periodic wakes of the rotor blades at the rotor/stator interface. A spanwise behaviour typical of flows through windmilling fans is evidenced. Through the inner sections of the fan, rotor wakes are thin and weakly turbulent, and the turbulence level remains constant through the stage. The rotor wakes thicken and become more turbulent towards the fan tip, where flow separation occurs. Downstream of the stator, maximum levels of turbulence intensity are measured in the separated flow. Large periodical zones of low velocity and high turbulence intensity are observed in the outer parts of the separated stator wake, confirming the pulsating motion of the stator flow separation, locked at the blade passing frequency. Space-time diagrams show that the flow is chorochronic, and a 2 D non-linear harmonic simulation is able to capture the main interaction modes, however, the stator incidence distribution could be affected by 3 D effects.

Because of their potential reductions of fuel consumption, disruptive propulsion concepts such as boundary layer ingestion have lately earned the attention of the aerospace community. Because of the increased level of interactions brought by the tight airframe–propulsor integration, an accurate assessment of this benefit requires a detailed study of the engine behavior from both an aerodynamics and an overall performance standpoint. In this context, this Paper presents a fully coupled methodology that integrates a zero-dimensional thermodynamic cycle analysis of the core and a three-dimensional body force representation of the fan stage into a single numerical computation. This approach allows the efficient simulation of fan–distortion interactions and engine overall performance in terms of accuracy vs computational cost tradeoff, making it well suited for conducting full aircraft–engine computational fluid dynamics calculations. The coupling is demonstrated in the assessment of boundary layer ingestion impacts on the small DGEN380 turbofan. Results provide a quantification of such impacts on fan efficiency, engine power demand, thrust specific fuel consumption, flow distortion transfer, and fan stage aeromechanical response, for different engine net thrust settings.

International audience; We report on a detailed numerical study of the two-phase operation of a surface alternating current dielectric barrier discharge actuator. We showcase that when the quasi-periodic regime has been established, residual volume and surface charges play an important role on the discharge evolution strongly coupling the positive and negative phases. It is shown that the quasi-neutral streamer discharge found on the positive phase serves as both a positive and negative charge generator and acts as a virtual anode. As the streamer is not attached to the dielectric surface, most of the surface charging occurs during its after-burn (relaxation) phase. The positive surface charge leads to an distant zone of high electric field and thus ion drift but also interacts majorly with the negative discharge phase. During the latter, microdischarges form near the active electrode and an intense cathode layer feeds with charges the discharge volume. Each microdischarge is followed by a plasma layer formation attached to the dielectric layer expanding further at each repetition until it occupies a volume linked to the streamer elongation length and positively charged surface portion. The strong coupling between the positive and negative phases along with the strong impact of the streamer discharge on both suggest implications that have been ignored so far in terms of electrohydrodynamic force production and its spatiotemporal distribution.

With more complex aircraft architectures, fast and cost-effective design iterations are key to improve overall fuel efficiency. This paper proposes to revisit a low-order unsteady modeling approach to replace costly full annulus URANS simulation. Unsteady Body Force Methods (UBFM) could allow a significant cost reduction for fan distortion ingestion and operability assessment. In this approach, the bladed area in the computational domain is replaced by source terms in the Navier–Stokes equations, and the cost of the simulation is reduced by a factor of 26. The operability of the fan is evaluated with and without distortion in order to assess the accuracy of the model. Previously published results of URANS simulations performed on the same fan subject to an unsteady vortex ingestion are used as reference.1 The results show that our UBFM is able to predict rotating stall cells, with patterns and rotating speed similar to the URANS data.

Background: The Aldrete's score is used to determine when a patient can safely leave the Post-Anaesthesia Care Unit (PACU) and be transferred to the surgical ward. The Aldrete score is based on the evaluation of vital signs and consciousness. Cognitive functions at the time the patient is judged fit for discharge from the PACU (Aldrete’s score ≥9) had not yet been studied. The aim of this trial was to assess the cognitive status of inpatients emerging either from desflurane or propofol anesthesia, at the time of PACU discharge (Aldrete score ≥9). Methods: Sixty adult patients scheduled for hip or knee arthroplasty under general anesthesia were randomly allocated to receive either desflurane or propofol anesthesia. Patients were evaluated the day before surgery using Digit Symbol Substitution Test, Stroop Test and Verbal Learning Test. After surgery, the Aldrete score was checked every 5 min until reaching a score ≥9. At this time, the same battery of cognitive tests was applied. Every tests were evaluated separately. Cognitive status was reported using a combined Z score pooling together the results all 3 cognitive tests. Results: Among the 3 tests, only DSST was significantly reduced at Aldrete Score ≥9 in the Dsflurane group. Combined Z-scores at Aldrete Score ≥9 were (in medians [interquartils]): -0.2 [-1.2;+0.6] and -0.4 [-1.1;+0.4] for desflurane and propofol groups respectively (P=0.62). The majority of patients did not present any cognitive dysfunction at Aldrete score ≥9 (24 patients out of 27 in the Propofol group and 23 patients out of 25 in the Desflurane group). Conclusion: An Aldrete score ≥9 was associated with satisfactory cognitive function recovery in the majority of the patients after a lower limb arthroplastic surgery under general anesthesia. No difference was observed between desflurane and propofol. This reinforces the clinical value of Aldrete score to state about ability to leave the PACU in safety conditions. Trial Registration: Clinical Trials identifier NCT 02036736

Inlet distortion can significantly impact turbofan operability. In the present contribution, the focus is on vortex ingestion, which is a type of distortion that has received less attention in the literature for high-bypass-ratio fans of civil engines than inlet separation or boundary layer ingestion. Due to the unsteady and non-axisymmetric nature of the inflow, full annulus computations are performed, using an unsteady RANS approach with a sliding mesh interface between the rotor and the stator. The goal is to provide a detailed analysis and understanding of the mechanisms responsible for operability loss when a vortex is ingested by the fan. To that end, a simplified model of vortex is derived from previous simulations in crosswind conditions including the presence of the ground plane. The study test case is a turbofan demonstrator representative of modern turbofans. Simulations are run with and without vortex at several operating points until rotating stall is observed. The global results show that the vortex ingestion induces a stall margin loss of up to 8%. Modal analysis indicates a stall pattern with 10 cells rotating at somewhere between 52 and 67% of the shaft speed. A comparison of the two configurations shows that the stall inception mechanism is similar with and without distortion. In particular, examining the incidence at the fan blade, a similar critical angle is observed for the two configurations, which is leveraged to establish a stall criterion valid for vortex ingestion cases.

New propulsive concepts, such as boundary layer ingestion, involve stronger interactions between the engine and its environment, and are thus more complex flows compared to classical architectures. Usual turbomachinery design tools are inadequate, and new numerical methodologies are needed to accurately predict the engine performance with affordable CPU resources. The present paper examines the relevance of a reduced-order modeling approach&mdash, the body force modeling (BFM) method&mdash, for a low-speed cooling fan with inflow distortion. The formulation itself accounts for the blade metal blockage and compressibility effects, and it relies on a semiempirical loss model, independent of computational fluid dynamics (CFD) calibration. The BFM results obtained in the present work are assessed against full-annulus unsteady Reynolds-averaged Navier-Stokes (URANS) results and experiments. The comparison shows that the BFM approach successfully quantifies the fan stage performance. Furthermore, the distortion transfer across the stage is examined and the flow patterns observed are found to be the same as in the URANS results and in the measurements. Hence, this methodology, coming at a low CPU cost, is well-adapted to the early design phase of an innovative propulsion system.

We show that the spatio-temporal ElectroHydroDynamic (EHD) force production in surface AC-Dielectric Barrier Discharge (AC-DBD) actuators is strongly influenced by both the streamer regime during the positive phase and the micro-discharge regime during the negative phase. Focusing on the spatial EHD force profiles, we demonstrate that the ionic wind spatial distribution can only be explained by the positive contribution of the streamer regime. The location of maximum ionic wind is found to be directly linked with the maximum elongation of the streamers at several millimeters from the exposed electrode. In both positive and negative phases of the AC-DBD operation, residual volumetric and surface charges once again linked to the streamer formation and afterburn, result to a variety of positive EHD force zones which, when time-averaged in one AC period, contribute to the generation of the experimentally observed induced thin wall jet. Through a thorough elaboration of our numerical results, we provide an illustrative explanation of the EHD force spatio-temporal evolution, showcase the importance of streamers and retrieve a correct representation of the ionic wind spatial profiles when compared to experiments., 12 pages, 7 figures; references added, title changed, structure modified and text enriched, figures updated (and added) for improved visualization/comprehension, abstract enriched; all results remain unchanged

International audience; Objective:To compare the oxidative stress induced by IV iron infusion in critically ill patients and in healthy volunteers.Design:Multicenter, interventional study.Setting:Two ICUs and one clinical research center.Subjects:Anemic critically ill patients treated with IV iron and healthy volunteers.Interventions:IV infusion of 100 mg of iron sucrose.Measurements and Main Results:Thirty-eight anemic patients (hemoglobin, median [interquartile range] = 8.4 g/dL [7.7–9.2]) (men, 25 [66%]; aged 68 yr [48–77]; Simplified Acute Physiology Score II, 48.5 [39–59]) and 39 healthy volunteers (men, 18 [46%]; aged 42.1 yr [29–50]) were included. Blood samples were drawn before (H0) and 2, 6, and 24 hours (H2, H6, and H24) after a 60-minute iron infusion for the determination of nontransferrin bound iron, markers of lipid peroxidation—8α-isoprostanes, protein oxidation—advanced oxidized protein product, and glutathione reduced/oxidized. Iron infusion had no effect on hemodynamic parameter in patients and volunteers. At baseline, patients had much higher interleukin-6, C-reactive protein, and hepcidin levels. 8α-isoprostanes was also higher in patients at baseline (8.5 pmol/L [6.5–12.9] vs 4.6 pmol/L [3.5–5.5]), but the area under the curve above baseline from H0 to H6 was not different (p = 0.38). Neither was it for advanced oxidized protein product and nontransferrin bound iron. The area under the curve above baseline from H0 to H6 (glutathione reduced/oxidized) was lower in volunteers (p = 0.009). Eight patients had a second set of dosages (after the fourth iron infusion), showing higher increase in 8α-isoprostanes.Conclusions:In our observation, IV iron infusion does not induce more nontransferrin bound iron, lipid, or protein oxidation in patients compared with volunteers, despite higher inflammation, oxidative stress, and hepcidin levels and lower antioxidant at baseline. In contrary, iron induces a greater decrease in antioxidant, compatible with higher oxidative stress in volunteers than in critically ill patients.

IntroductionTracheal intubation remains an everyday challenge for anaesthesiologists, even in patients without suspected difficult airways. The ideal positioning of the patient’s head (flat, raised a few centimetres on a cushion in the sniffing position (SP), or raised to achieve horizontal alignment between the external acoustic meatus and the sternal angle) and the use of videolaryngoscopy remain controversial. This trial aims to compare the efficacy for orotracheal intubation of the SP or the head-elevated laryngoscopy position (HELP), which has been shown to improve laryngeal visualization and the intubation condition particularly in obese patients, in combination with a McGrath Mac videolaryngoscope whose video screen is either on or off (Video or NoVideo).Methods and analysisThe HELP-VDL factorial trial is a prospective, randomised, parallel, multicentre, open study of 240 adult patients undergoing tracheal intubation under general anaesthesia. Patients will be allocated into four groups: SP-NoVideo, HELP-NoVideo, SP-Video and HELP-Video. The primary outcome is the proportion of orotracheal intubations that requires the assistance of a nurse anaesthetist. The secondary outcomes include the intubation duration, the first intubation success rate, the quality of visualisation of the glottis, the glottis visualisation score, adjunctive manoeuvres and alternative techniques used, the occurrence of oesophageal intubation, failure of tracheal intubation, the incidence of arterial oxygen desaturation, the perception of a difficult intubation, the score on the Intubation Difficulty Scale, cooperation among the members of the anaesthesia team, the evolution of vital signs and the frequency and severity of intubation complications. Data will be analysed on the intention-to-treat principle and a per-protocol basis.Ethics and disseminationEthics approval was obtained from the Ethical Committee Ile de France V (Paris, France). Participant recruitment began on 3 July 2019. The results will be submitted for publication in peer-reviewed journals.Trial registration numberNCT03987009; Pre-results.