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Rapid, mass diagnosis of the coronavirus disease 2019 (COVID-19) is critical to stop the ongoing infection spread. The two standard screening methods to confirm the severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) are polymerase chain reaction (PCR), through the RNA of the virus, and serology by detecting antibodies produced as a response to the viral infection. However, given the detection complexity, cost and relatively long analysis times of these techniques, novel technologies are urgently needed. Here, we report an aptamer-based biosensor developed on a screen-printed carbon electrode platform for rapid, sensitive, and user-friendly detection of SARS-CoV-2. The aptasensor relies on an aptamer targeting the receptor-binding domain (RBD) in the spike protein (S-protein) of the SARS-CoV-2. The aptamer immobilization on gold nanoparticles, and the presence of S-protein in the aptamer-target complex, investigated for the first time by photo-induced force microscopy mapping between 770 and 1910 cm -1 of the electromagnetic spectrum, revealed abundant S-protein homogeneously distributed on the sensing probe. The detection of SARS-CoV-2 S-protein was achieved by electrochemical impedance spectroscopy after 40 min incubation with several analyte concentrations, yielding a limit of detection of 1.30 pM (66 pg/mL). Moreover, the aptasensor was successfully applied for the detection of a SARS-CoV-2 pseudovirus, thus suggesting it is a promising tool for the diagnosis of COVID-19.

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In this article I propose that the introduction of the alphabet to post-Dark Age Greece, in the first years of the 8th c. BCE, led within a generation to an explosion of figurative representations in vase painting and contributed to the inception of narrative techniques that stayed with Greek art ever since. Specifically, it is suggested that the Dipylon Master may have had some knowledge of writing and that his experience with letters had repercussions in his work as a painter. The outlines of and relationship between letters in a written word must have offered him and other late Geometric artists a stimulus for pursuing these implications in the world of painting.

This study presents an atypical burial from the Late Roman cemetery at Histria. During previous archaeological excavations at the same site and the Scythia Province, no such discoveries were identified. This case consists of a burial in a simple pit with coffin and ordinary inventory, and an atypical re-inhumation which disturbed the first skeleton. The anthropological analysis identified two individuals under 20 years old, who displayed musculo-skeletal markers of physical activity. This feature is less common for this age category.