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Background Nasopharyngeal antigen Rapid Diagnostic Tests (RDTs), saliva RT-PCR and nasopharyngeal (NP) RT-PCR have shown different performance characteristics to detect patients infected by SARS-CoV-2, according to the viral load (VL)—and thus transmissibility. Methods In October 2020, we conducted a prospective trial involving patients presenting at testing centres with symptoms of COVID-19. We compared detection rates and performance of RDT, saliva PCR and nasopharyngeal (NP) PCR, according to VL and symptoms duration. Results Out of 949 patients enrolled, 928 patients had all three tests performed. Detection rates were 35.2% (95%CI 32.2–38.4%) by RDT, 39.8% (36.6–43.0%) by saliva PCR, 40.1% (36.9–43.3%) by NP PCR, and 41.5% (38.3–44.7%) by any test. For those with viral loads (VL) ≥106 copies/ml, detection rates were 30.3% (27.3–33.3), 31.4% (28.4–34.5), 31.5% (28.5–34.6), and 31.6% (28.6–34.7%) respectively. Sensitivity of RDT compared to NP PCR was 87.4% (83.6–90.6%) for all positive patients, 94.5% (91.5–96.7%) for those with VL≥105 and 96.5% (93.6–98.3%) for those with VL≥106. Sensitivity of STANDARD-Q®, Panbio™ and COVID-VIRO® Ag tests were 92.9% (86.4–96.9%), 86.1% (78.6–91.7%) and 84.1% (76.9–89.7%), respectively. For those with VL≥106, sensitivity was 96.6% (90.5–99.3%), 97.8% (92.1–99.7%) and 95.3% (89.4–98.5%) respectively. No patient with VLConclusions RDT results allow rapid identification of COVID cases with immediate isolation of most contagious individuals. RDT can thus be a game changer both in ambulatory care and community testing aimed at stopping transmission chains, and even more so in resource-constrained settings thanks to its very low price. When PCR is performed, saliva could replace NP swabbing. Trial registration ClinicalTrial.gov Identifier: NCT04613310 (03/11/2020).

Six new rare-earth orthoborates NaBaR(BO3)2, with R = Tb, Dy, Ho, Er, Tm, Lu were synthesized using a multiple-step solid-state reaction. These new orthoborates continue the previously described isostructural lines of three-cation orthoborates NaBaR(BO3)2, by R = Sc, Y, Yb. The structure of synthesized solid compounds is isotypic with the mineral eitelite, Na2Mg(CO3)2, crystallizing in the trigonal system with space group R3. All prepared borates are isostructural, as evidenced by the presence of the same vibration modes in Raman spectra and of the same diffraction peaks in X-ray patterns. The photoluminescence of NaBaTb(BO3)2 have been investigated in a detail.

This article takes a new look at the temporal configuration imagined by reformers and revolutionaries of the nineteenth century in France, as Eugène Pottier’s poetry makes particularly clear (When will it happen ?, Internationalism…). Such temporalities seem to be caught between remembering political experiences and waiting for the return of the social Republic. Inseparable from historical times and rhythms, they are specific to the nineteenth century. But their social meaning can be approached from three different angles: religious (the millennial belief in salvation), political (waiting for the event to take place), and sentimental (waiting for one’s next love). It is permissible to state that the temporalities of the project of social emancipation contained in Pottier’s writings must not be reduced to a substitute millennialism, for we discern in them a more secular temporality of expectation that renounces the desire for eternity, while still preserving a sense of the infinite.