Studies of low-energy ionic collisions Final report, 1 Oct. 1965 - 30 Sep. 1967

Ionic-molecular collisions, and collision induced dissociation of ion

A Dual Read-Out Assay to Evaluate the Potency of Compounds Active against Mycobacterium tuberculosis

PMCID: PMC3617142This is an open-access article distributed under the terms of the Creative Commons Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original author and source are credited

Solution of an infection model near threshold

We study the Susceptible-Infected-Recovered model of epidemics in the vicinity of the threshold infectivity. We derive the distribution of total outbreak size in the limit of large population size $N$. This is accomplished by mapping the problem to the first passage time of a random walker subject to a drift that increases linearly with time. We recover the scaling results of Ben-Naim and Krapivsky that the effective maximal size of the outbreak scales as $N^{2/3}$, with the average scaling as $N^{1/3}$, with an explicit form for the scaling function

Invasion threshold in heterogeneous metapopulation networks

We study the dynamics of epidemic and reaction-diffusion processes in metapopulation models with heterogeneous connectivity pattern. In SIR-like processes, along with the standard local epidemic threshold, the system exhibits a global invasion threshold. We provide an explicit expression of the threshold that sets a critical value of the diffusion/mobility rate below which the epidemic is not able to spread to a macroscopic fraction of subpopulations. The invasion threshold is found to be affected by the topological fluctuations of the metapopulation network. The presented results provide a general framework for the understanding of the effect of travel restrictions in epidemic containment.Comment: 4 pages, 2 figure

High Energy Physics from High Performance Computing

We discuss Quantum Chromodynamics calculations using the lattice regulator. The theory of the strong force is a cornerstone of the Standard Model of particle physics. We present USQCD collaboration results obtained on Argonne National Lab's Intrepid supercomputer that deepen our understanding of these fundamental theories of Nature and provide critical support to frontier particle physics experiments and phenomenology.Comment: Proceedings of invited plenary talk given at SciDAC 2009, San Diego, June 14-18, 2009, on behalf of the USQCD collaboratio

Numerical analysis of droplet deposition in inkjet printed electronics assembly

In this paper, a computational approach for the analysis of microscale droplet impact dynamics is presented. The approach is intended to support a condition based monitoring system to enhance quality and reliability of inkjet printed electronics components. The Smoothed Particle Hydrodynamics (SPH) approach of Lucy and Gingold and Monaghan has been used as the basis for the model, with the δ-SPH terms of Marrone et al used to improve handling of the dynamic impact events and the gradient correction terms of Belytschko used to improve the accuracy of interface dynamics. Model validation has been performed through comparison against a macroscale dam break problem and through a microscale analysis designed to determine accurate surface tension-pressure behaviour based on the Young-Laplace relation. The model is used to assess impact of a single drop on a uniform surface and the three dimensional formation of multi-drop layers

D→K,lνD \rightarrow K, l \nu Semileptonic Decay Scalar Form Factor and ∣Vcs∣|V_{cs}| from Lattice QCD

We present a new study of D semileptonic decays on the lattice which employs the Highly Improved Staggered Quark (HISQ) action for both the charm and the light valence quarks. We work with MILC unquenched $N_f = 2 + 1$ lattices and determine the scalar form factor $f_0(q^2)$ for $D \rightarrow K, l \nu$ semileptonic decays. The form factor is obtained from a scalar current matrix element that does not require any operator matching. We develop a new approach to carrying out chiral/continuum extrapolations of $f_0(q^2)$. The method uses the kinematic "$z$" variable instead of $q^2$ or the kaon energy $E_K$ and is applicable over the entire physical $q^2$ range. We find $f^{D \rightarrow K}_0(0) \equiv f^{D \rightarrow K}_+(0) = 0.747(19)$ in the chiral plus continuum limit and hereby improve the theory error on this quantity by a factor of $\sim$4 compared to previous lattice determinations. Combining the new theory result with recent experimental measurements of the product $f^{D \rightarrow K}_+(0) * |V_{cs}|$ from BaBar and CLEO-c leads to the most precise direct determination of the CKM matrix element $|V_{cs}|$ to date, $|V_{cs}| = 0.961(11)(24)$, where the first error comes from experiment and the second is the lattice QCD theory error. We calculate the ratio $f^{D \rightarrow K}_+(0)/f_{D_s}$ and find $2.986 \pm 0.087$ GeV$^{-1}$ and show that this agrees with experiment.Comment: 23 pages, 31 figures, 11 tables. Added a paragraph in sction VII, and updated with PDG 2010 instead of PDG 200

Modelling methodologies for quality assessment of 3D inkjet printed electronic products

Purpose of the Fraunhofer Direct Digital Manufacturing Conference is an intellectual exchange between researchers, enterprises and users of Additive Manufacturing technologies in order to gather the latest information about trends, progress, importance and the future potential of these technologies for industrial applications. The range of topics covers Product Development (incl. simulation, co-design, mass customization), Technologies (incl. bio-printing, hybrid processes, novel developments/visionary concepts, process chains for industrial production), Materials (incl. ceramics, bio-materials, multi-material approaches), Quality (incl. process/ part quality management) as well as further innovative and visionary approaches not fitting the range of topics above. Renowned international keynote speakers give insight into the latest trends and challenges in additive manufacturing in a variety of industry sectors, including biomedical, aerospace and automotive