Surfaces decorated with dense arrays of microscopic fibres exhibit unique materials properties, including superhydrophobicity and low friction. Nature relies on 'hairy' surfaces to protect blood capillaries from wear and infection (endothelial glycocalyx). Here we report on the discovery of self-assembled tunable networks of microscopic polymer fibres ranging from wavy colloidal 'fur' to highly interconnected networks. The networks emerge via dynamic selfassembly in an alternating electric field from a non-aqueous suspension of 'sticky' polymeric colloidal particles with a controlled degree of polymerization. The resulting architectures are tuned by the frequency and amplitude of the electric field and surface properties of the particles. We demonstrate, using atomic layer deposition, that the networks can serve as a template for a transparent conductor. These self-assembled tunable materials are promising candidates for large surface area electrodes in batteries and organic photovoltaic cells, as well as for microfluidic sensors and filters.

High invasiveness and resistance to chemo- and radiotherapy of glioblastoma multiforme (GBM) make it the most lethal brain tumor. Therefore, new treatment strategies for preventing migration and invasion of GBM cells are needed. Using two different migration assays, Western blotting, conventional and super-resolution (dSTORM) fluorescence microscopy we examine the effects of the dual PI3K/mTOR-inhibitor PI-103 alone and in combination with the Hsp90 inhibitor NVP-AUY922 and/or irradiation on the migration, expression of marker proteins, focal adhesions and F-actin cytoskeleton in two GBM cell lines (DK-MG and SNB19) markedly differing in their invasive capacity. Both lines were found to be strikingly different in morphology and migration behavior. The less invasive DK-MG cells maintained a polarized morphology and migrated in a directionally persistent manner, whereas the highly invasive SNB19 cells showed a multipolar morphology and migrated randomly. Interestingly, a single dose of 2 Gy accelerated wound closure in both cell lines without affecting their migration measured by single-cell tracking. PI-103 inhibited migration of DK-MG (p53 wt, PTEN wt) but not of SNB19 (p53 mut, PTEN mut) cells probably due to aberrant reactivation of the PI3K pathway in SNB19 cells treated with PI-103. In contrast, NVP-AUY922 exerted strong anti-migratory effects in both cell lines. Inhibition of cell migration was associated with massive morphological changes and reorganization of the actin cytoskeleton. Our results showed a cell line-specific response to PI3K/mTOR inhibition in terms of GBM cell motility. We conclude that anti-migratory agents warrant further preclinical investigation as potential therapeutics for treatment of GBM.

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INTRODUCTIONNiobium silicide-based alloys have a wide range of applications including tunnel barriers for Josephson junctions, 1 superconductors for particle detection (bolometers), 2,3 and low friction and high temperature corrosion resistant coatings for engines. 4 Thin films of Nb x Si 1Àx compounds with various compositions can be deposited using a variety of methods including electron beam evaporation 5,6 (Nb 5 Si 3 and NbSi 2 ), RF magnetron sputtering, 7 explosive or arc melting and chill-casting 8À10 (NbSi 3 ), chemical vapor deposition, 11 direct laser fabrication, 12 or ion-induced formation. 13 In contrast with these line-of-sight techniques, atomic layer deposition (ALD) offers many advantages. ALD is a thin film deposition technique that uses alternating, self-limiting chemical reactions between gaseous precursors and a solid surface to deposit materials in an atomic layer-by-layer fashion. 14 The self-terminating chemistry coupled with gaseous diffusion of the precursor vapors allows an excellent control of both the composition and the thickness uniformity on arbitrary complexshaped objects. ALD has been used previously to deposit a wide range of materials including metals, metal oxides, and metal nitrides, but only metal silicides have received relatively little attention. 15 To our knowledge this is the first reported in-depth growth study for the ALD of a pure silicide.There has been only one previous report for the ALD of superconducting materials. 16 Despite the fact that very little effort has been invested in the growth study of superconductors by ALD, this unique technique could clearly beneficiate a variety of low-temperature superconductor-based applications that are currently limited by line-of-sight deposition techniques. Bolometers are one example. 2,3 Another example is superconducting radio frequency (SRF) accelerating niobium cavities 17 used is almost all particle accelerators around the world.This study pursues dual goals: first, to develop a low temperature, reliable ALD process to synthesize NbSi with a high growth rate that can open the way to other transition metal silicide or NbSi-based alloys growth study by ALD and, second, to characterize and optimize the superconducting properties of the NbSi films. In this study we use alternating exposures to NbF 5 and Si 2 H 6 to deposit NbSi films by ALD. In-situ quartz crystal microbalance (QCM) and quadrupole mass spectrometer (QMS) measurements are used to explore the mechanism for the NbSi ALD. A variety of ex-situ techniques are used to determine the physical properties of the films. X-ray reflectivity (XRR) measurements are used to evaluate the thickness, roughness, and density of the films while Rutherford backscattering spectroscopy (RBS) is employed to determine the density and stoichiometry of the films. The composition and impurity content of the films are evaluated using X-ray photoelectron spectroscopy (XPS), and scanning electron microscopy (SEM) is utilized to examine the uniformity and conformality of the coatings on no...