Hydrogen sensing characteristics of Pt/TiO2/MWCNTs composites

Platinum-doped titanium-dioxide/multi-walled carbon nanotubes (Pt/TiO₂/MWCNTs) composites were prepared by a sol-gel method and characterized by x-ray diffraction (XRD), scanning electron microscopy (SEM), transmission electron microscopy (TEM), thermo-gravimetry (TG) and micro-Raman spectroscopy (MRS). Regardless the nominal C/Ti molar ratio (0.3–17.0), only the anatase phase of TiO₂ was detected. However, on the composite with the highest C/Ti molar ratio, the formation of a more structurally disordered and non-stoichiometric anatase phase seemed to be favored. Small Pt nanoparticles, whose size ranged from 1 to 10 nm, were observed dispersed on the surface of composite samples.     

Micro-Raman investigation of vanadium-oxide coated tubular carbon nanofibers for gas-sensing applications

Commercial tubular carbon nanofibers were uniformly coated with a 5 nm thick vanadium oxide layer via a modified approach to atomic layer deposition. The composition and microstructure of the resulting hybrid material was analyzed by micro-Raman spectroscopy. The effect of the post-synthesis thermal treatment in air at temperatures in the range of 25–375 °C was investigated in order to more deeply understand the behavior of the hybrid material in gas sensing devices. The obtained results demonstrate that the thermal treatment primarily affects the oxide coating-layer that is responsible for the sensing properties. The best sensor performance was obtained at the temperature at which the oxide layered-structure exhibits the highest structural order.     

Combined effect of lignosulfonate and carbonate on pure portland clinker compounds hydration. I. Tetracalcium aluminoferrite hydration

The combined effect of sodium lignosulfonate and sodium carbonate on the C₄AF hydration was examined by DTG and TG curves and by zeta potential measurements. In the presence of lignosulfonate-carbonate systems the C₄AF hydration is completely blocked. The higher the percentage of admixtures, the longer is this induction period. Moreover a strong change in the zeta potential is caused by the simultaneous addition of lignosulfonate and carbonate. Both the strong retarding action and the dispersing effect caused by the change in the zeta potential could explain the liquefying effect of the admixtures. After the induction period the C₄AF hydration is strongly accelerated by the lignosulfonate-carbonate system.     

Mild Innate Immune Activation Overrides Efficient Nanoparticle-Mediated RNA Delivery

Clinical mRNA delivery remains challenging, in large part because how physiology alters delivery in vivo remains underexplored. For example, mRNA delivered by lipid nanoparticles (LNPs) is being considered to treat inflammation, but whether inflammation itself changes delivery remains understudied. Relationships between immunity, endocytosis, and mRNA translation lead to hypothesize that toll-like receptor 4 (TLR4) activation reduced LNP-mediated mRNA delivery. Therefore, LNP uptake, endosomal escape, and mRNA translation with and without TLR4 activation are quantified. In vivo DNA barcoding is used to discover a novel LNP that delivers mRNA to Kupffer cells at clinical doses; unlike most LNPs, this LNP does not preferentially target hepatocytes. TLR4 activation blocks mRNA translation in all tested cell types, without reducing LNP uptake; inhibiting TLR4 or its downstream effector protein kinase R improved delivery. The discrepant effects of TLR4 on i) LNP uptake and ii) translation suggests TLR4 activation can “override” LNP targeting, even after mRNA is delivered into target cells. Given near-future clinical trials using mRNA to modulate inflammation, this highlights the need to understand inflammatory signaling in on- and off-target cells. More generally, this suggests an LNP which delivers mRNA to one inflammatory disease may not deliver mRNA to another.     

Optimized cloud-based scheduling for protein secondary structure analysis

The Journal of Supercomputing - In the domain of proteomics, an in-depth analysis of the 3D structure of a protein is of paramount importance for many biological studies and applications. At the...