A 2D percolation-based model for characterizing the piezoresistivity of carbon nanotube-based films

Carbon nanotubes (CNTs) have attracted considerable attention due to their unique electrical, mechanical, and electromechanical properties. In particular, thin films formed by embedding CNTs in polymer matrices have been shown to exhibit strain-sensitive electromechanical properties, which can serve as an alternative to traditional strain sensors. Although numerous experimental studies have characterized their electrical properties and piezoresistivity, it remains unclear as to what nano-scale mechanisms dominate to govern nanocomposite electromechanical properties. Therefore, the objective of this study is to create a two-dimensional (2D) percolation-based numerical model to understand the electrical and coupled electromechanical behavior of CNT-based thin films. First, a percolation-based model with randomly dispersed straight nanotubes was generated. Second, the percolation and unstrained electrical properties of the model were evaluated as a function of CNT density and length. Next, uniaxial tensile–compressive strains were applied to the model for characterizing their electromechanical response and piezoresistivity. In addition, the effects of different intrinsic strain sensitivities of individual nanotubes were also considered. The results showed that bulk film strain sensitivity was strongly related to CNT density, length, and its intrinsic strain sensitivity. In particular, it was found that strain sensitivity decreased with increasing CNT density. While these strain sensitivity trends were consistent for different intrinsic CNT gage factors, the results were more complicated near the percolation threshold. These results were also compared to other experimental research so as to understand how different nano-scale parameters propagate and affect bulk film response

An experimental and numerical study on the mechanical properties of carbon nanotube-latex thin films

This research was supported by the U.S. National Science Foundation (NSF) under grant number CMMI-CAREER 1253564 and supplement CMMI-CAREER 1542532. In addition, N.M.P. acknowledges support by the European Research Council (ERC StG Ideas 2011 BIHSNAM no. 279985, ERC PoC 2013-2 KNOTOUGH no. 632277, ERC PoC 2015 SILKENE no. 693670), by the European Commission under the Graphene Flagship (WP10 ‘Nanocomposites’, no. 604391) and by the Provincia Autonoma di Trento (‘Graphene nanocomposites’, no. S116/2012-242637 and reg. delib. no. 2266). L.B. and F.B. are supported by BIHSNAM. Computational resources were provided by HPC@POLITO (http://www.hpc.polito.it

The South Asian genome

Genetics of disease Microarrays Variant genotypes Population genetics Sequence alignment AllelesThe genetic sequence variation of people from the Indian subcontinent who comprise one-quarter of the world's population, is not well described. We carried out whole genome sequencing of 168 South Asians, along with whole-exome sequencing of 147 South Asians to provide deeper characterisation of coding regions. We identify 12,962,155 autosomal sequence variants, including 2,946,861 new SNPs and 312,738 novel indels. This catalogue of SNPs and indels amongst South Asians provides the first comprehensive map of genetic variation in this major human population, and reveals evidence for selective pressures on genes involved in skin biology, metabolism, infection and immunity. Our results will accelerate the search for the genetic variants underlying susceptibility to disorders such as type-2 diabetes and cardiovascular disease which are highly prevalent amongst South Asians.Whole genome sequencing to discover genetic variants underlying type-2 diabetes, coronary heart disease and related phenotypes amongst Indian Asians. Imperial College Healthcare NHS Trust cBRC 2011-13 (JS Kooner [PI], JC Chambers)

Some Like It Fat: Comparative Ultrastructure of the Embryo in Two Demosponges of the Genus Mycale (Order Poecilosclerida) from Antarctica and the Caribbean

0000-0002-7993-1523© 2015 Riesgo et al. This is an open access article distributed under the terms of the Creative Commons Attribution License [4.0], which permits unrestricted use, distribution, and reproduction in any medium, provided the original author and source are credited. The attached file is the published version of the article

Observation of associated near-side and away-side long-range correlations in √sNN=5.02 TeV proton-lead collisions with the ATLAS detector

Two-particle correlations in relative azimuthal angle (Δϕ) and pseudorapidity (Δη) are measured in √sNN=5.02  TeV p+Pb collisions using the ATLAS detector at the LHC. The measurements are performed using approximately 1  μb-1 of data as a function of transverse momentum (pT) and the transverse energy (ΣETPb) summed over 3.1<η<4.9 in the direction of the Pb beam. The correlation function, constructed from charged particles, exhibits a long-range (2<|Δη|<5) “near-side” (Δϕ∼0) correlation that grows rapidly with increasing ΣETPb. A long-range “away-side” (Δϕ∼π) correlation, obtained by subtracting the expected contributions from recoiling dijets and other sources estimated using events with small ΣETPb, is found to match the near-side correlation in magnitude, shape (in Δη and Δϕ) and ΣETPb dependence. The resultant Δϕ correlation is approximately symmetric about π/2, and is consistent with a dominant cos⁡2Δϕ modulation for all ΣETPb ranges and particle pT

Measurement of the inclusive and dijet cross-sections of b-jets in pp collisions at sqrt(s) = 7 TeV with the ATLAS detector

The inclusive and dijet production cross-sections have been measured for jets containing b-hadrons (b-jets) in proton-proton collisions at a centre-of-mass energy of sqrt(s) = 7 TeV, using the ATLAS detector at the LHC. The measurements use data corresponding to an integrated luminosity of 34 pb^-1. The b-jets are identified using either a lifetime-based method, where secondary decay vertices of b-hadrons in jets are reconstructed using information from the tracking detectors, or a muon-based method where the presence of a muon is used to identify semileptonic decays of b-hadrons inside jets. The inclusive b-jet cross-section is measured as a function of transverse momentum in the range 20 < pT < 400 GeV and rapidity in the range |y| < 2.1. The bbbar-dijet cross-section is measured as a function of the dijet invariant mass in the range 110 < m_jj < 760 GeV, the azimuthal angle difference between the two jets and the angular variable chi in two dijet mass regions. The results are compared with next-to-leading-order QCD predictions. Good agreement is observed between the measured cross-sections and the predictions obtained using POWHEG + Pythia. MC@NLO + Herwig shows good agreement with the measured bbbar-dijet cross-section. However, it does not reproduce the measured inclusive cross-section well, particularly for central b-jets with large transverse momenta.Comment: 10 pages plus author list (21 pages total), 8 figures, 1 table, final version published in European Physical Journal