Magnetofection potentiates gene delivery to cultured endothelial cells

Modification of cellular functions by overexpression of genes is increasingly practised for research of signalling pathways, but restricted by limitations of low efficiency. We investigated whether the novel technique of magnetofection (MF) could enhance gene transfer to cultured primary endothelial cells. MF of human umbilical vein endothelial cells (HUVEC) increased transfection efficiency of a luciferase reporter gene up to 360-fold compared to various conventional transfection systems. In contrast, there was only an up to 1.6-fold increase in toxicity caused by MF suggesting that the advantages of MF outbalanced the increase in toxicity. MF efficiently increased transfection efficiency using several commercially available cationic lipid transfection reagents and polyethyleneimine (PEI). Using PEI, even confluent HUVEC could be efficiently transfected to express luciferase activity. Using a green fluorescent protein vector maximum percentages of transfected cells amounted up to 38.7% while PEI without MF resulted in only 1.3% transfected cells. Likewise, in porcine aortic endothelial cells MF increased expression of a luciferase or beta-galactosidase reporter, reaching an efficiency of 37.5% of cells. MF is an effective tool for pDNA transfection of endothelial cells allowing high efficiencies. It may be of great use for investigating protein function in cell culture experiments

Tunable magnetism on the lateral mesoscale by post-processing of Co/Pt heterostructures

Controlling magnetic properties on the nm-scale is essential for basic research in micro-magnetism and spin-dependent transport, as well as for various applications such as magnetic recording, imaging and sensing. This has been accomplished to a very high degree by means of layered heterostructures in the vertical dimension. Here we present a complementary approach that allows for a controlled tuning of the magnetic properties of Co/Pt heterostructures on the lateral mesoscale. By means of in-situ post-processing of Pt- and Co-based nano-stripes prepared by focused electron beam induced deposition (FEBID) we are able to locally tune their coercive field and remanent magnetization. Whereas single Co-FEBID nano-stripes show no hysteresis, we find hard-magnetic behavior for post-processed Co/Pt nano-stripes with coercive fields up to 850 Oe. We attribute the observed effects to the locally controlled formation of the CoPt L1$_{0}$ phase, whose presence has been revealed by transmission electron microscopy.Comment: Accepted for publication in Beilstein J. Nanotechno

ConfIDent – An Open Platform for FAIR Conference Metadata

Currently, information on scientific events such as conferences is often scattered and not available in the long term. With the project ConfIDent we want to develop a service platform for the quality-driven, collaborative curation of semantically structured metadata of scientific events. It will provide reliable and transparent data and workflows for researchers (organizers, speakers, participants) as well as other stakeholders of scientific events such as university administrations, libraries, sponsors, publishers or specialized societies. The sustainability of the service will not only be obtained a user-centered approach but also by connecting it to existing services enabling data exchange, and by the commitment to the FAIR principles. ConfIDent will reach the current desideratum of long-term findable, open, referenceable and reusable metadata on scientific events.DFG/Wissenschaftskommunikation, Forschungsdaten, eResearch (Wissenschaftliche Literaturversorgungs- und Informationssysteme)/426477583/E

confIDent - for FAIR conference metadata

This poster describes the development of a sustainable platform for the permanent and reliable storage and provision of conference metadata in the DFG funded project confIDent

Remote monitoring to predict bridge scour failure using Interferometric Synthetic Aperture Radar (InSAR) stacking techniques

Scour is the removal of ground material in water bodies due to environmental changes in water flow. It particularly occurs at bridge piers and the holes formed can make bridges susceptible to collapse. The most common cause of bridge collapse is due to scour occurring during flooding, some failures causing loss of life and most resulting in significant transport disruption and economic loss. Consequently, failure of bridges due to scour is of great concern to bridge asset owners, and is currently very difficult to predict since conventional assessment methods foresee very resource-demanding monitoring efforts in situ. This paper presents evidence of how InSAR techniques can be used to monitor bridges at risk of scour, using Tadcaster Bridge, England, as a case study. Tadcaster Bridge suffered a partial collapse due to river scour on the evening of December 29th, 2015 following a period of severe rainfall and flooding. 48 TerraSAR-X scenes over the bridge from the two-year period prior to the collapse are analysed using the small baseline subset (SBAS) interferometric synthetic aperture radar (InSAR) approach. The study highlights a distinct movement in the region of the bridge where the collapse occurred prior to the actual event. This precursor to failure observed in the data over a month before actual collapse suggests the possible use of InSAR as a means of an early warning system in structural health monitoring of bridges at risk of scour.This work was made possible by EPSRC (UK) Award 1636878, with iCase sponsorship from the National Physical Laboratory and additional funding from Laing O’Rourke

Stability analysis of chemically modified mRNA using micropattern-based single-cell arrays

The measurement of mRNA turnover in living cells plays an important role in the search for stable mRNA constructs for RNA-based therapies. Here we show that automated time-lapse microscopy combined with micropatterned arrays allows for efficient high-throughput monitoring of fluorescent reporter protein expression at the single-cell level. The fluorescence time courses after mRNA transfection yield the distribution of individual mRNA expression and degradation rates within a population. We compare mRNA constructs with combinations of 5′ and 3′ UTR sequences and find a systematic broadening and shift towards longer functional half-lives for UTR stabilized mRNA. At the same time the life time distribution of the destabilized EGFP reporter protein was found to be constant and narrowly distributed. Using mathematical modeling, we show that mRNA functional life-time predicts the time-integrated protein level, i.e. the area under the curve (AUC) of mRNA translation. Our approach paves the way for quantitative assessment of hitherto unexplored mRNA functional life time heterogeneity, possibly predicated on multiple mRNA secondary structures and its dependence on UTR sequences

Stability analysis of chemically modified mRNA using micropattern-based single-cell arrays

The measurement of mRNA turnover in living cells plays an important role in the search for stable mRNA constructs for RNA-based therapies. Here we show that automated time-lapse microscopy combined with micropatterned arrays allows for efficient high-throughput monitoring of fluorescent reporter protein expression at the single-cell level. The fluorescence time courses after mRNA transfection yield the distribution of individual mRNA expression and degradation rates within a population. We compare mRNA constructs with combinations of 5′ and 3′ UTR sequences and find a systematic broadening and shift towards longer functional half-lives for UTR stabilized mRNA. At the same time the life time distribution of the destabilized EGFP reporter protein was found to be constant and narrowly distributed. Using mathematical modeling, we show that mRNA functional life-time predicts the time-integrated protein level, i.e. the area under the curve (AUC) of mRNA translation. Our approach paves the way for quantitative assessment of hitherto unexplored mRNA functional life time heterogeneity, possibly predicated on multiple mRNA secondary structures and its dependence on UTR sequences