Accounting: A General Commentary on an Empirical Science

Many researchers have questioned the view of accounting as a science. Some maintain that it is a service activity rather than a science, yet others entertain the view that it is an art or merely a technology. While it is true that accounting provides a service and is a technology (a methodology for recording and reporting), that fact does not prevent accounting from being a science. Based upon the structure and knowledge base of the discipline, this paper presents the case for accounting as an empirical science

Polycaprolactone membranes reinforced by toughened sol-gel produced silica networks

The aim of this work is to develop polycaprolactone based porous materials with improved mechanical performance to be used in bone repair. The hybrid membranes consist in a polymeric porous material in which the pore walls are coated by a silica thin layer. Silica coating increases membrane stiffness with respect to pure polymer but in addition filling the pores of the polymer with a silica phase improves bioactivity due to the delivery of silica ions in the neighborhood of the material in vivo. Nevertheless silica network, even that produced by sol–gel, might be too stiff and brittle what is not desirable for its performance as a coating. In this work we produced a toughened silica coating adding chitosan and 3-glycidoxypropyltrimethoxysilane (GPTMS) to the precursor solution looking for having polymer chains linked by covalent bonding to the silica network. Hybrid polymer–silica coating was produced by in situ sol–gel reaction using Tetraethyl orthosilicate (TEOS), GPTMS and chitosan. Chemical reaction between amine groups of chitosan chains and epoxy groups of GPTMS allowed covalent bonding of polymer chains to the silica network. Physical properties of the hybrid membranes were characterized and cell attachment of MC3T3-E1 pre-osteoblastic cells on the surface of these supports was assessed.Fundação para a Ciência e a Tecnologia (FCT)CEPB acknowledges the economic support of COOPEN agreement in the progress of the present work. JFM acknowledges the support from Fundac¸a˜o para a Cieˆncia e Tecnologia through project PTDC/FIS/115048/2009. JLGR acknowledges the support of the Spanish Ministry of Education through project No. MAT2010-21611-C03-01. CIBER-BBN is an initiative funded by the VI National R&D&i Plan 2008-2011, Iniciativa Ingenio 2010, Consolider Program, CIBER Actions and financed by the Instituto de Salud Carlos III with assistance from the European Regional Development Fund. Authors want to thank the technical support of the Universitat Polite`cnica de Vale`ncia’s Microscopy Service

VizieR Online Data Catalog: Velocity precision in the Gaia-ESO Survey (Jackson+, 2015)

The Gaia-ESO Survey (GES) is a large public spectroscopic survey at the European Southern Observatory Very LargeTelescope. A key aim is to provide precise radial velocities (RVs) and projected equatorial velocities (vsini) for representative samples of Galactic stars, which will complement information obtained by the Gaia astrometry satellite. We present an analysis to empirically quantify the size and distribution of uncertainties in RV and vsini using spectra from repeated exposures of the same stars. We show that the uncertainties vary as simple scaling functions of signal-to-noise ratio (S/N) and vsini, that the uncertainties become larger with increasing photospheric temperature, but that the dependence on stellar gravity, metallicity and age is weak. The underlying uncertainty distributions have extended tails that are better represented by Students t-distributions than by normal distributions. Parametrised results are provided, which enable estimates of the RV precision for almost all GES measurements, and estimates of the vsini precision for stars in young clusters, as a function of S/N, vsini and stellar temperature. The precision of individual high S/N GES RV measurements is 0.22-0.26km/s, dependent on instrumental configuration. (1 data file). <P /