We have prepared solutions of multiwalled carbon nanotubes in Aroclor 1254, a mixture of polychlorinated biphenyls. The solutions are stable at room temperature. Transport measurements were performed using a scanning-tunneling probe on a sample prepared by spin coating the solution on gold substrates. Conductance steps were clearly seen. A histogram of a high number of traces shows maximum peaks at integer values of the conductance quantum G(0)=2e(2)/h, demonstrating ballistic transport at room temperature along the carbon nanotube over distances longer than 1.4 microm.

Critical illness in COVID-19 is an extreme and clinically homogeneous disease phenotype that we have previously shown1 to be highly efficient for discovery of genetic associations2. Despite the advanced stage of illness at presentation, we have shown that host genetics in patients who are critically ill with COVID-19 can identify immunomodulatory therapies with strong beneficial effects in this group3. Here we analyse 24,202 cases of COVID-19 with critical illness comprising a combination of microarray genotype and whole-genome sequencing data from cases of critical illness in the international GenOMICC (11,440 cases) study, combined with other studies recruiting hospitalized patients with a strong focus on severe and critical disease: ISARIC4C (676 cases) and the SCOURGE consortium (5,934 cases). To put these results in the context of existing work, we conduct a meta-analysis of the new GenOMICC genome-wide association study (GWAS) results with previously published data. We find 49 genome-wide significant associations, of which 16 have not been reported previously. To investigate the therapeutic implications of these findings, we infer the structural consequences of protein-coding variants, and combine our GWAS results with gene expression data using a monocyte transcriptome-wide association study (TWAS) model, as well as gene and protein expression using Mendelian randomization. We identify potentially druggable targets in multiple systems, including inflammatory signalling (JAK1), monocyte–macrophage activation and endothelial permeability (PDE4A), immunometabolism (SLC2A5 and AK5), and host factors required for viral entry and replication (TMPRSS2 and RAB2A).

The results of this study show that carotid IMT measurement using THI sonography and a standardized protocol is accurate and reproducible.

Thermal fluctuation of the cantilever position sets a fundamental limit for the precision of any Scanning Force Microscope. In the present work we analyse how these fluctuations limit the determination of the resonance frequency of the tip-sample system. The basic principles of frequency detection in Dynamic Scanning Force Microscopy are revised and the precise response of a typical frequency detection unit to thermal fluctuation of the cantilever is analysed in detail. A general relation for thermal frequency noise is found as a function of measurement bandwidth and cantilever oscillation. For large oscillation amplitude and low bandwidth, this relation converges to the result known from the literature, while for low oscillation amplitude and large bandwidth we find that the thermal frequency noise is equal to the width of the resonance curve and therefore stays finite, contrary to what is predicted by the relation known so far. The results presented in this work fundamentally determine the ultimate limits of Dynamic Scanning Force Microscopy. 1 arXiv:1002.4284v2 [cond-mat.mes-hall]

Mixtures of poly(3‐octylthiophene) (P3OT) with graphite nanoparticles have been investigated by scanning force microscopy (SFM) techniques. The morphology as well as the mechanical and electrical properties of the blends has been characterized at the nanoscale level as a function of the carbon nanoparticle content in the blend. An increase in the concentration of carbon nanoparticles results in an increase in the surface roughness of the blend and the appearance of distinct regions with well‐defined electrical and mechanical properties. At intermediate concentrations (5–10 wt % of carbon nanoparticles), the samples show pure P3OT regions, as well as round regions containing a mixture of the polymer and carbon nanoparticles, while at higher concentrations (> 15 wt %), the entire sample is composed of this mixture. The interface between the two regions has been studied by electrostatic scanning force microscopy (ESFM) as a function of the applied tip–sample voltage. ESFM provides evidence for the creation of new electronic states at the heterojunction. The observed results can be qualitatively explained in terms of the electronic properties of the individual molecular components, P3OT, functionalized graphite nanoparticles, and their corresponding heterojunction. The implications of these results for organic polymer solar cells are also discussed.

Locally resolved electrostatic force spectroscopy is combined with Kelvin force microscopy to compare the results obtained using either the force or the frequency as signal source for tip-sample interaction. A two-component locally heterogeneous sample—islands of octadecanethiol molecules self-assembled on Au(111)—is used as a nanometer scale model system. On this kind of sample, electrostatic force spectroscopy as well as Kelvin force microscopy clearly demonstrate that local and quantitative electrostatic force microscopy has to be implemented with the frequency as the signal source.

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