14,418 research outputs found
Recent developments in classical density functional theory: Internal energy functional and diagrammatic structure of fundamental measure theory
An overview of several recent developments in density functional theory for
classical inhomogeneous liquids is given. We show how Levy's constrained search
method can be used to derive the variational principle that underlies density
functional theory. An advantage of the method is that the Helmholtz free energy
as a functional of a trial one-body density is given as an explicit expression,
without reference to an external potential as is the case in the standard
Mermin-Evans proof by reductio ad absurdum. We show how to generalize the
approach in order to express the internal energy as a functional of the
one-body density distribution and of the local entropy distribution. Here the
local chemical potential and the bulk temperature play the role of Lagrange
multipliers in the Euler-Lagrange equations for minimiziation of the
functional. As an explicit approximation for the free-energy functional for
hard sphere mixtures, the diagrammatic structure of Rosenfeld's fundamental
measure density unctional is laid out. Recent extensions, based on the
Kierlik-Rosinberg scalar weight functions, to binary and ternary non-additive
hard sphere mixtures are described.Comment: 15 pages, 6 figure
A pilot validation in 10 European Union Member States of a point prevalence survey of healthcare-associated infections and antimicrobial use in acute hospitals in Europe, 2011
Phenotypic analysis of host-parasite interactions in lambs infected with Teladorsagia circumcincta
Microprogram scheme for automatic recovery from computer error
Microprogram scheme enables computer to recover from failure in one of its two central processing units during time duration of instruction in which failure occurs. Microprogram advantages include - /1/ built-in interpretive capability, /2/ selection of processing interrupts by priority, and /3/ economical use of bootstrap sequence
New actors and new strategies after NPM reforms: coping with a trust crisis in collective bargaining across nine EU member states
Repetitive Segmental Structure of the Transducin β Subunit: Homology with the CDC4 Gene and Identification of Related mRNAs
Retinal transducin, a guanine nucleotide regulatory protein (referred to as a G protein) that activates a cGMP phosphodiesterase in photoreceptor cells, is comprised of three subunits. We have identified and analyzed cDNA clones of the bovine transducin β subunit that may be highly conserved or identical to that in other G proteins. From the cDNA nucleotide sequence of the entire coding region, the primary structure of a 340-amino acid protein was deduced. The encoded β subunit has a Mr of 37,375 and is comprised of repetitive homologous segments arranged in tandem. Furthermore, significant homology in primary structure and segmental sequence exists between the β subunit and the yeast CDC4 gene product. The Mr 37,375 β subunit polypeptide is encoded by a 2.9-kilobase (kb) mRNA. However, there exists in retina other β-related mRNAs that are divergent from the 2.9-kb mRNA on the basis of oligonucleotide and primer-extended probe hybridizations. All mammalian tissues and clonal cell lines that have been examined contain at least two β-related mRNAs, usually 1.8 and 2.9 kb in length. These results suggest that the mRNAs are the processed products of a small number of closely related genes or of a single highly complex β gene
Calibration of the Ames Anechoic Facility. Phase 1: Short range plan
A calibration was made of the acoustic and aerodynamic characteristics of a small, open-jet wind tunnel in an anechoic room. The jet nozzle was 102 mm diameter and was operated subsonically. The anechoic-room dimensions were 7.6 m by 5.5 m by 3.4 m high (wedge tip to wedge tip). Noise contours in the chamber were determined by various jet speeds and exhaust collector positions. The optimum nozzle/collector separation from an acoustic standpoint was 2.1 m. Jet velocity profiles and turbulence levels were measured using pressure probes and hot wires. The jet was found to be symmetric, with no unusual characteristics. The turbulence measurements were hampered by oil mist contamination of the airflow
Diffuse supernova neutrinos: oscillation effects, stellar cooling and progenitor mass dependence
We estimate the diffuse supernova neutrino background (DSNB) using the recent
progenitor-dependent, long-term supernova simulations from the Basel group and
including neutrino oscillations at several post-bounce times. Assuming
multi-angle matter suppression of collective effects during the accretion
phase, we find that oscillation effects are dominated by the matter-driven MSW
resonances, while neutrino-neutrino collective effects contribute at the 5-10%
level. The impact of the neutrino mass hierarchy, of the time-dependent
neutrino spectra and of the diverse progenitor star population is 10% or less,
small compared to the uncertainty of at least 25% of the normalization of the
supernova rate. Therefore, assuming that the sign of the neutrino mass
hierarchy will be determined within the next decade, the future detection of
the DSNB will deliver approximate information on the MSW-oscillated neutrino
spectra. With a reliable model for neutrino emission, its detection will be a
powerful instrument to provide complementary information on the star formation
rate and for learning about stellar physics.Comment: 19 pages, including 4 figures and 1 table. Clarifying paragraphs
added; results unchanged. Matches published version in JCA
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