What science for what democracy?

The transformations undergone by research and science in the name of the so called "knowledge economy" cover the decisions of scientific policies and the "management" of research, and also the meaning of scientific activities (devoted to innovation) and even more fundamentally the very structure of the sciences (transformed to technosciences). The science that is contributing to capitalist competitiveness (and to the current economic crisis) is not the same as that which would be able to contribute "to the conception and democratic carrying out of another form of globalization and another European project". However, this is not self-evident, and it needs to be thought about since it is not simply a matter of returning to the science of the 20th century that opened the way to technoscience

Visualization of SARS-CoV-2 particles in naso/oropharyngeal swabs by thin section electron microscopy

Background SARS-CoV-2 replicates efficiently in the upper airways of humans and produces high loads of virus RNA and, at least in the initial phase after infection, many infectious virus particles. Studying virus ultrastructure, such as particle integrity or presence of spike proteins, and effects on their host cells in patient samples is important to understand the pathogenicity of SARS-CoV-2. Methods Suspensions from swab samples with a high load of virus RNA (Ct < 20) were sedimented by desktop ultracentrifugation and prepared for thin section electron microscopy using a novel method which is described in detail. Embedding was performed in Epon or in LR White resin using standard or rapid protocols. Thin sections were examined using transmission electron microscopy. Results Virus particles could be regularly detected in the extracellular space, embedded in a background of heterogenous material (e.g. vesicles and needle-like crystals), and within ciliated cells. Morphology (i.e. shape, size, spike density) of virus particles in the swab samples was very similar to particle morphology in cell culture. However, in some of the samples the virus particles hardly revealed spikes. Infected ciliated cells occasionally showed replication organelles, such as double-membrane vesicles. The most common cells in all samples were keratinocytes from the mucosa and bacteria. Conclusions The new method allows the ultrastructural visualization and analysis of coronavirus particles and of infected host cells from easy to collect naso/oropharyngeal patient swab samples.Peer Reviewe

Charge transport in nanoscale vertical organic semiconductor pillar devices

We report charge transport measurements in nanoscale vertical pillar structures incorporating ultrathin layers of the organic semiconductor poly(3-hexylthiophene)(P3HT). P3HT layers with thickness down to 5 nm are gently top-contacted using wedging transfer, yielding highly reproducible, robust nanoscale junctions carrying high current densities (up to $10^6$ A/m$^2$). Current-voltage data modeling demonstrates excellent hole injection. This work opens up the pathway towards nanoscale, ultrashort-channel organic transistors for high-frequency and high-current-density operation.Comment: 30 pages, 8 figures, 1 tabl

Vertical aerosol particle exchange in the marine boundary layer estimated from helicopter-borne measurements in the Azores region

Aerosol particles are important for radiation effects, cloud formation, and therefore the climate system. A detailed understanding of the spatial distribution of aerosol particles within the atmospheric boundary layer, which depends on sources and sinks, as well as long-range transport and vertical exchange, is important. Especially in marine regions, where the climate effect of clouds is comparably high, long-range transport with subsequent vertical mixing dominates over local aerosol sources. In this study, three different methods were applied to estimate the vertical aerosol particle flux in the marine boundary layer (MBL) and the vertical exchange between the MBL and the free troposphere (FT): eddy covariance (EC), flux–gradient similarity (K theory), and the mixed-layer gradient method (MLG). For the first time, MBL aerosol fluxes derived from these three methods were compared in the framework of the “Azores Stratocumulus Measurements of Radiation, Turbulence and Aerosols” (ACORES) field campaign in the Azores region in the northeastern Atlantic Ocean in July 2017. Meteorological parameters and aerosol and cloud properties were measured in the marine troposphere using the helicopter-borne measurement platform ACTOS (Airborne Cloud Turbulence Observation System). All three methods were applied to estimate the net particle exchange between MBL and FT. In many cases, the entrainment fluxes of the MLG method agreed within the range of uncertainty with the EC and K-theory flux estimates close to the top of the MBL, while the surface flux estimates of the different methods diverged. It was not possible to measure directly above the surface with the helicopter-borne payload, which might be a source of uncertainty in the surface fluxes. The observed particle fluxes at the top of the MBL ranged from 0 to 10×106 m−2 s−1 both in the upward and the downward direction, and the associated uncertainties were on the same order of magnitude. Even though the uncertainties of all three methods are considerable, the results of this study contribute to an improved understanding of the transport of particles between the MBL and FT and their distribution in the MBL

Morphometry of SARS-CoV and SARS-CoV-2 particles in ultrathin plastic sections of infected Vero cell cultures

SARS-CoV-2 is the causative of the COVID-19 disease, which has spread pandemically around the globe within a few months. It is therefore necessary to collect fundamental information about the disease, its epidemiology and treatment, as well as about the virus itself. While the virus has been identified rapidly, detailed ultrastructural analysis of virus cell biology and architecture is still in its infancy. We therefore studied the virus morphology and morphometry of SARS-CoV-2 in comparison to SARS-CoV as it appears in Vero cell cultures by using conventional thin section electron microscopy and electron tomography. Both virus isolates, SARS-CoV Frankfurt 1 and SARS-CoV-2 Italy-INMI1, were virtually identical at the ultrastructural level and revealed a very similar particle size distribution with a median of about 100 nm without spikes. Maximal spike length of both viruses was 23 nm. The number of spikes per virus particle was about 30% higher in the SARS-CoV than in the SARS-CoV-2 isolate. This result complements a previous qualitative finding, which was related to a lower productivity of SARS-CoV-2 in cell culture in comparison to SARS-CoV.Peer Reviewe

Een asymmetrische snel progressieve tonsillaire tumor bij een kind van zes jaar

Het Burkitt-lymfoom is een slecht gedifferentieerd, zeldzaam en agressief type van het non-hodgkinlymfoom. In dit artikel beschrijven wij een casus van een meisje van zes jaar, die zich presenteerde in het Sophia Kinderziekenhuis van het Erasmus MC (Erasmus MC – Sophia) met een snel progressieve, inspiratoire stridor en een bedreigde luchtweg op basis van een forse asymmetrische suspecte zwelling van de tonsil rechts. Met een beenmergaspiraat werd de diagnose Burkitt-lymfoom bevestigd en behandeling met chemotherapie ingezet. Hierop slonk de tumor binnen enkele dagen aanzienlijk, zodat operatief ingrijpen om de luchtweg veilig te stellen, niet meer nodig was