Facile Fabrication of Porous Conductive Thermoplastic Polyurethane Nanocomposite Films via Solution Casting

Content of Dataset 1. FTIR spectra 2. Tensile Properties 3. Conductivity 4. Piezoresistive Properties 5. Resistance vs. Strain 6. Porosity Notes : This dataset is linked to Paper: Scientific Reports,2017,DOI: 10.1038/s41598-017-17647-

Preparation of 4 '-spirocyclobutyl nucleoside analogues as novel and versatile adenosine scaffolds

Despite the large variety of modified nucleosides that have been reported, the preparation of constrained 4 '-spirocyclic adenosine analogues has received very little attention. We discovered that the [2+2]-cycloaddition of dichloroketene on readily available 4 '-exo-methylene furanose sugars efficiently results in the diastereoselective formation of novel 4 '-spirocyclobutanones. The reaction mechanism was investigated via density functional theory (DFT) and found to proceed either via a non-synchronous or stepwise reaction sequence, controlled by the stereochemistry at the 3 '-position of the sugar substrate. The obtained dichlorocyclobutanones were converted into nucleoside analogues, providing access to a novel class of chiral 4 '-spirocyclobutyl adenosine mimetics in eight steps from commercially available sugars. Assessment of the biological activity of designed 4 '-spirocyclic adenosine analogues identified potent inhibitors for protein methyltransferase target PRMT5

Virus-induced gene complementation reveals a transcription factor network in modulation of tomato fruit ripening

Plant virus technology, in particular virus-induced gene silencing, is a widely used reverse- and forward-genetics tool in plant functional genomics. However the potential of virus technology to express genes to induce phenotypes or to complement mutants in order to understand the function of plant genes is not well documented. Here we exploit Potato virus X as a tool for virus-induced gene complementation (VIGC). Using VIGC in tomato, we demonstrated that ectopic viral expression of LeMADS-RIN, which encodes a MADS-box transcription factor (TF), resulted in functional complementation of the non-ripening rin mutant phenotype and caused fruits to ripen. Comparative gene expression analysis indicated that LeMADS-RIN up-regulated expression of the SBP-box (SQUAMOSA promoter binding protein-like) gene LeSPL-CNR, but down-regulated the expression of LeHB-1, an HD-Zip homeobox TF gene. Our data support the hypothesis that a transcriptional network may exist among key TFs in the modulation of fruit ripening in tomato

Site-specific protein modification using immobilized sortase in batch and continuous-flow systems

Transpeptidation catalyzed by ​sortase A allows the preparation of proteins that are site-specifically and homogeneously modified with a wide variety of functional groups, such as fluorophores, PEG moieties, lipids, glycans, bio-orthogonal reactive groups and affinity handles. This protocol describes immobilization of ​sortase A on a solid support (Sepharose beads). Immobilization of ​sortase A simplifies downstream purification of a protein of interest after labeling of its N or C terminus. Smaller batch and larger-scale continuous-flow reactions require only a limited amount of enzyme. The immobilized enzyme can be reused for multiple cycles of protein modification reactions. The described protocol also works with a Ca²⁺-independent variant of ​sortase A with increased catalytic activity. This heptamutant variant of ​sortase A (7M) was generated by combining previously published mutations, and this immobilized enzyme can be used for the modification of calcium-senstive substrates or in instances in which low temperatures are needed. Preparation of immobilized ​sortase A takes 1–2 d. Batch reactions take 3–12 h and flow reactions proceed at 0.5 ml h⁻¹, depending on the geometry of the reactor used.United States. National Institutes of Health (RO1 AI087879

A self-healing, adaptive and conductive polymer composite ink for 3D printing of gas sensors

A graphene/polyborosiloxane composite exhibited self-healing, adaptive and electrically conductive properties and could be 3D printed into gas sensors.</p

Mechanically Adaptive and Shape-Memory Behaviour of Chitosan-Modified Cellulose Whisker/Elastomer Composites in Different pH Environments

Biomimetic polymer composites with water-active mechanically adaptive and shape-memory behaviour in different pH environments are synthesised by using chitosan-modified cellulose whiskers (CS-CWs) as the stimulus-responsive phase and thermoplastic polyurethane (TPU) as the resilient matrix. The effect of surface modification on the mechanically adaptive behaviour of CS-CW/TPU composites is investigated by using three representative solutions with various pH values. The results show that surface modification significantly enhances the modulus contrast under wet and dry conditions with the acidic solution as the stimulus, while maintaining the high modulus contrast with the basic solution as the stimulus. CS-CW/TPU composites also exhibit excellent shape-memory effects in all three solutions that are comparable to those pristine CW/TPU composites. Furthermore, activation of force generation in the stretched CS-CW/TPU composites by water absorption/desorption was observed.</p

Carbon nanotube/polypropylene composite particles for microwave welding

Multiwalled carbon nanotube (MWCNT)/polypropylene (PP) composite particles with various compositions were prepared by mechanical grinding of PP microparticles and MWCNT powders in a mortar at room temperature. Scanning electron microscopy (SEM) revealed that PP particles were coated by MWCNTs, forming a core-shell structure. The electrical resistivity versus temperature behavior of MWCNT/PP composite particles and the changes in phase structures before and after melting were studied. Furthermore, MWCNT/PP composite particles with 4 wt % MWCNT were used to weld PP substrates under microwave irradiation. The effects of the irradiation duration and the compression pressure on the welding strength were examined. Here, we have demonstrated a simple and economic method for polymer welding