Domaines d’élection

Si l'élection est un domaine de prédilection de la science politique, c'est aussi parce que cet objet canonique participe à la visibilité sociale de la discipline voire, par ricochet, à sa légitimité. Il y a sans doute, alors, des bénéfices scientifiques à attendre d'études qui, laissant de côté l'histoire immédiate du vote, portent sur quelques-uns des instruments d'analyse et des concepts utilisés dans cet acte rituel : le commentaire de l'élection. [Premier paragraphe de l'éditorial

Moving to two's complement sign representation

We propose to implement the change to abandon ones complement and sign-and-magnitude representationfrom C. Main efforts are made to maintain interface compatibility with C++’s recently voted changes, thatis to ensure that value and object representations are exchangeable.This is a follow-up to document N22181 which found positive WG14 support to make two’scomplement the only sign representation for the next C standard

Group testing as a strategy for COVID-19 epidemiological monitoring and community surveillance

International audienceWe propose an analysis and applications of sample pooling to the epidemiologic monitoring of COVID-19. We first introduce a model of the RT-qPCR process used to test for the presence of virus in a sample and construct a statistical model for the viral load in a typical infected individual inspired by large-scale clinical datasets. We then propose a method for the measure of the prevalence in a population, based on group testing, taking into account the increased number of false negatives associated with this method. Finally, we present an application of sample pooling for the prevention of epidemic outbreak in closed connected communities

Active strike-slip faulting in the Chablais area (NW Alps) from earthquake focal mechanisms and relative locations

Abstract.: The Chablais area is characterized by a complex geological setting, resulting from the transport of nappes of various internal origins (the Prealpine nappes), thrusted in Oligocene times onto the Helvetic cover of the external zones of the Alps. While the structural setting and timing of nappe emplacement are well understood, current tectonics and associated faulting remain unclear. The detailed analysis of the Bonnevaux and Samoëns earthquakes, presented in this study, constitutes a significant contribution to the active tectonics of the Chablais area. The associated seismotectonic regime appears to be constant with depth, both focal mechanisms yielding a strike-slip regime, one in the crystalline basement at around 17km depth and the other probably cross-cutting the cover/basement interface at around 5km depth. Relative location techniques, applied in this study to the seismic sequence associated to the Samoëns earthquake, represents the best way to identify active faults in a region where neotectonic evidence is scarce and controversial. The resulting seismic alignment corresponds to the E-W oriented nodal plane inferred from the Samoëns main shock focal mechanism, thus defining an active near vertical E-W dextral fault. This strike-slip regime, compared to the current regional stress field, corresponds to the one observed in the Jura/Molasse basin area but contrasts with the exclusively dextral and NE-SW-oriented transcurrent regime of the Wildhorn/Martigny regio

Congenital lung malformations: correlation between prenatal and postnatal imaging and pathological findings

Aim: Congenital lung malformations are a common finding during prenatal ultrasonography (US). Investigations were completed by means of prenatal MRI and postnatal computed tomographic (CT) scan. The purpose of this study was to compare these prenatal findings with postnatal findings and pathological findings after surgical resection.Materials and methods: Prenatal examinations and postnatal CTscan results of congenital malformations were compared with pathological findings.Results: From 2007 to 2013, 39 prenatally diagnosed congenital lung malformations were resected: 18 congenital cystic adenomatoid malformation, eight pulmonary sequestration, five bronchogenic cyst, one bronchial atresia and six complex lesions. Correlation between imaging and diagnosis was as follows: congenital cystic adenomatoid malformation was seen in 17/17 patients using postnatal CT, in 10/15 patients using prenatal MRI and in 17/18 patients using prenatal US. Correlation between imaging and diagnosis was as follows: bronchogenic cyst was seen in 3/5, 3/5 and 3/5 patients, pulmonary sequestration was seen in 7/9, 5/9 and 4/9 patients, and complex lesion was seen in 4/5, 3/6, and 2/6 patients using postnatal CT, prenatal MRI, and prenatal US,  respectively. Overall, 32/37 cases were diagnosed by means of postnatal CT, 21/36 cases were diagnosed by means of prenatal MRI and 26/39 cases were diagnosed by means of prenatal US.Conclusion: Discordance between imaging data and definitive diagnosis is not rare. Our results suggest that postnatal CT scan is the most sensible and specific examination. Before birth, US seems better compared with MRI for description of the lesion. MRI seems to be useful in case of complex lesions and pulmonary sequestration.Keywords: congenital lung malformation, imaging, prenata

Double reading of outsourced CT/MR radiology reports

OBJECTIVES: Our objective was to determine disagreement rates in radiological reports provided by using a double-reading protocol in a national teleradiology company. METHODS: From January 2015 to July 2016, 134169 radiological exams from 36 French centers, benefited outsourced interpretations by certified radiologists, in both regular and after-hours activities. Of these, 2040 CT and MR-scans (1.5%) were subjected to a second opinion by other radiologists in the field of their anatomical specialty (cerebral, thoracic, abdominal-pelvic, and osteoarticular). A five-point agreement scale graded from 0 to 4 was assigned for each exam. Disagreements were considered as minor if no clinical consequence for patient (scores 1 and 2) and major if potential clinical consequence (score 3 and 4). Independent radiologists performed a retrospective analysis and a stratified statistical analysis. RESULTS: Double reading was performed on CT-scans (n = 934/2040, 45.8%) and MR-scans (n = 1106/2040, 54.2%) performed in regular (80.1%) and after-hours activities (19.9%). Disagreement scores occurred in 437 exams (21.4%), including major disagreements in 59 (2.9%). Among these, 48/754 were assigned by the thoracic second reader (6.4%), 6/70 by the abdominal-pelvic second reader (8.6%), 3/901 by the osteoarticular second reader (0.3%), and 2/315 by the cerebral second reader (0.6%), with statistical significant difference. No additional disagreement rate was observed in regular and after-hours activities (P = 0.63). CONCLUSIONS: Double-reading of outsourced CT and MRI interpretations yielded 21.4% disagreement rate, with potential clinical consequence for patient in 2,9% of the cases. These results are in accordance with those previously reported and suggests that quality assurance of outsourced interpretations is needed

Fusion de données RVB-D par stéréophotométrie colorée

Nous montrons comment utiliser la stéréophotométrie colorée pour améliorer le relief fourni par un capteur RVB-D. Le capteur est équipé de trois LEDs colorées, de telle sorte que l’image RVB permet de retrouver les détails les plus fins du relief, grâce à la stéréophotométrie. Cette estimation fine du relief est fusionnée avec la carte de profondeur fournie par le capteur, grâce à une nouvelle approche variationnelle de la stéréophotométrie adaptée aux sources ponctuelles anisotropes de type LED. Cette approche, qui est à la fois différentielle et variationnelle, permet d’estimer la profondeur directement et de façon robuste, sans estimation préalable des normales et de l’albédo. Elle offre donc un cadre naturel pour la prise en compte d’un a priori sur la profondeur, tel que le relief grossier fourni par le capteur RVB-D

In vitro prediction of stop-codon suppression by intravenous gentamicin in patients with cystic fibrosis: a pilot study

BACKGROUND: Cystic fibrosis (CF) is caused by mutations in the gene encoding the cystic fibrosis transmembrane conductance regulator (CFTR) protein, which acts as a chloride channel activated by cyclic AMP (cAMP). The most frequent mutation found in 70% of CF patients is F508del, while premature stop mutations are found in about 10% of patients. In vitro aminoglycoside antibiotics (e.g. gentamicin) suppress nonsense mutations located in CFTR permitting translation to continue to the natural termination codon. Pharmacologic suppression of stop mutations within the CFTR may be of benefit to a significant number of patients. Our pilot study was conducted to determine whether intravenous gentamicin suppresses stop codons in CF patients and whether it has clinical benefits. METHODS: A dual gene reporter system was used to determine the gentamicin-induced readthrough level of the most frequent stop mutations within the CFTR in the French population. We investigated readthrough efficiency in response to 10 mg/kg once-daily intravenous gentamicin perfusions in patients with and without stop mutations. Respiratory function, sweat chloride concentration, nasal potential difference (NPD) and CFTR expression in nasal epithelial cells were measured at baseline and after 15 days of treatment. RESULTS: After in vitro gentamicin incubation, the readthrough efficiency for the Y122X mutation was at least five times higher than that for G542X, R1162X, and W1282X. In six of the nine patients with the Y122X mutation, CFTR immunodetection showed protein at the membrane of the nasal epithelial cells and the CFTR-dependent Cl(- )secretion in NPD measurements increased significantly. Respiratory status also improved in these patients, irrespective of the gentamicin sensitivity of the bacteria present in the sputum. Mean sweat chloride concentration decreased significantly and normalised in two patients. Clinical status, NPD and sweat Cl(- )values did not change in the Y122X patients with no protein expression, in patients with the other stop mutations investigated in vitro and those without stop mutations. CONCLUSION: Suppression of stop mutations in the CFTR gene with parenteral gentamicin can be predicted in vitro and is associated with clinical benefit and significant modification of the CFTR-mediated Cl(- )transport in nasal and sweat gland epithelium