Racism and necropolitics: a debate between social theory and psychoanalysis

Taking Covid-19 Pandemic as a context and analyzer, this article discusses the historical links between racism and the medicalized management of the right to life and death in Brazil. It is based on the understanding that listening and clinical management of situations of psychological distress in the context of the medicalization of life (in Pandemic, and even outside it) necessarily imply making social criticism as well. To this end, we propose a debate that encapsulates clinical theory, the histories of social medicine and psychoanalysis in Brazil, and the concepts of bio and necropoli-tics. Our hypothesis is that if, on the one hand, on its arrival in Brazil, psychoanalysis was “co-opted” by a hygienist medical tradition (which for years polarized the way it was seen in our country), on the other, by its conceptual structure, by the initial counterpoint with Brazilian modernism, and by its current debate on segregation, this praxis can make explicit its anti-racist power and vocation. © 2020. All Rights Reserved.

Detection of a SARS-CoV-2 sequence with genosensors using data analysis based on information visualization and machine learning techniques

We report on genosensors to detect an ssDNA sequence from the SARS-CoV-2 genome, which mimics the GU280 gp10 gene (coding the viral nucleocapsid phosphoprotein), using four distinct principles of detection and treating the data with information visualization and machine learning techniques. Genosensors were fabricated on either gold (Au) interdigitated electrodes for electrical and electrochemical measurements or on Au nanoparticles on a glass slide for optical measurements. They contained a matrix of 11-mercaptoundecanoic acid (11-MUA) self-assembled monolayer (SAM) onto which a layer of capture probe (cpDNA) sequence was immobilized. Detection was performed using electrical and electrochemical impedance spectroscopies and localized surface plasmon resonance (LSPR). The highest sensitivity was reached with impedance spectroscopy, including using a low-cost (US$ 100) homemade impedance analyzer. Complementary ssDNA sequences were detected with a detection limit of 0.5 aM (0.3 copy per mu L). This performance may be attributed to the high sensitivity of the electrical impedance technique combined with an appropriate arrangement of the sequences on the electrodes and hybridization between the complementary sequences, as inferred from polarization-modulated infrared reflection absorption spectroscopy (PM-IRRAS). The selectivity of the genosensor was confirmed by plotting the impedance spectroscopy data with a multidimensional projection technique (interactive document mapping, IDMAP), where a clear separation was observed among the samples of the complementary DNA sequence at various concentrations and from buffer samples containing a non-complementary sequence and other DNA biomarkers. The diagnosis of SARS-CoV-2 mimicking sequences was also achieved with machine learning techniques applied to scanning electron microscope images taken from genosensors exposed to distinct concentrations of the complementary ssDNA sequences. In summary, the genosensors proposed here are promising for detecting SARS-CoV-2 genetic material (RNA) in biological fluids in point-of-care settings.