DISPERSION IN THE WOOD MOUSE, APODEMUS-SYLVATICUS - VARIABLE RESOURCES IN TIME AND SPACE

(1) The abundance and dispersion of a population of Apodemus sylvaticus was investigated with respect to tree seed availability and vegetative structure over three harvests.

Dispersion interactions in room-temperature ionic liquids: Results from a non-empirical density functional

The role of dispersion or van de Waals (VDW) interactions in imidazolium-based room-temperature ionic liquids is studied within the framework of density functional theory, using a recently developed non-empirical functional [M. Dion, H. Rydberg, E. Schroder, D. C. Langreth, and B. I. Lundqvist, Phys. Rev. Lett. 92, 246401 (2004)], as efficiently implemented in the SIESTA code [G. Roman-Perez and J. M. Soler, Phys. Rev. Lett. 103, 096102 (2009)]. We present results for the equilibrium structure and lattice parameters of several crystalline phases, finding a general improvement with respect to both the local density (LDA) and the generalized gradient approximations (GGA). Similar to other systems characterized by VDW bonding, such as rare gas and benzene dimers as well as solid argon, equilibrium distances and volumes are consistently overestimated by approximate to 7%, compared to -11% within LDA and 11% within GGA. The intramolecular geometries are retained, while the intermolecular distances and orientations are significantly improved relative to LDA and GGA. The quality is superior to that achieved with tailor-made empirical VDW corrections ad hoc [M. G. Del Popolo, C. Pinilla, and P. Ballone, J. Chem. Phys. 126, 144705 (2007)]. We also analyse the performance of an optimized version of this non-empirical functional, where the screening properties of the exchange have been tuned to reproduce high-level quantum chemical calculations [J. Klimes, D. Bowler, and A. Michaelides, J. Phys.: Condens. Matter 22, 074203 (2010)]. The results for solids are even better with volumes and geometries reproduced within 2% of experimental data. We provide some insight into the issue of polymorphism of [bmim][Cl] crystals, and we present results for the geometry and energetics of [bmim][Tf] and [mmim][Cl] neutral and charged clusters, which validate the use of empirical force fields. (C) 2011 American Institute of Physics. [doi:10.1063/1.3652897]

Absorbing new knowledge in small and medium-sized enterprises: A multiple case analysis of Six Sigma

The primary aim of this article is to critically analyse the development of Six Sigma theory and practice within small and medium-sized enterprises (SMEs) using a multiple case study approach. The article also explores the subsequent development of Lean Six Sigma as a means of addressing the perceived limitations of the efficacy of Six Sigma in this context. The overarching theoretical framework is that of absorptive capacity, where Six Sigma is conceptualized as new knowledge to be absorbed by smaller firms. The findings from a multiple case study involving repeat interviews and focus groups informed the development of an analytical model demonstrating the dynamic underlying routines for the absorptive capacity process and the development of a number of summative propositions relating the characteristics of SMEs to Six Sigma and Lean Six Sigma implementation.

AUDIT OF ANTIBIOTIC USAGE IN A MEDIUM-SIZED GENERAL-HOSPITAL OVER AN 11-YEAR PERIOD - THE IMPACT OF ANTIBIOTIC POLICIES

The objective of the present study was to evaluate trends in antibiotic expenditure over an 11-year period (1982-1992) in a 370-bed district general hospital in Northern Ireland and to examine the impact of two separate antibiotic policies on antibiotic usage. A further objective was to examine the attitudes of prescribers to the second policy. Drug utilization review was used to collect information on antibiotic expenditure and usage before and after introduction of separate antibiotic policies in 1985 (not intensively monitored) and 1989 (intensively monitored). A mail questionnaire was used to determine the attitudes of prescribers. The first policy (1985) showed no benefits with regard to the number of antibiotic entities stocked (45 before, 45 after), number of dosage units issued (9.35 increase) or expenditure (33.35 increase). The 1989 policy led to significant reductions in the number of antibiotic entities stocked (28.9%), number of antibiotics issued (11.9%) and expenditure (6.1%). Expenditure began to spiral upwards when active monitoring of the second policy was suspended. The majority of prescribers (87.2%) who responded to the questionnaire (56.5% response rate) felt that the 1989 policy made a positive contribution to antibiotic usage in the hospital.

Massive stars exploding in a He-rich circumstellar medium - I. Type Ibn (SN 2006jc-like) events

We present new spectroscopic and photometric data of the Type Ibn supernovae 2006jc, 2000er and 2002ao. We discuss the general properties of this recently proposed supernova family, which also includes SN 1999cq. The early-time monitoring of SN 2000er traces the evolution of this class of objects during the first few days after the shock breakout. An overall similarity in the photometric and spectroscopic evolution is found among the members of this group, which would be unexpected if the energy in these core-collapse events was dominated by the interaction between supernova ejecta and circumstellar medium. Type Ibn supernovae appear to be rather normal Type Ib/c supernova explosions which occur within a He-rich circumstellar environment. SNe Ibn are therefore likely produced by the explosion of Wolf-Rayet progenitors still embedded in the He-rich material lost by the star in recent mass-loss episodes, which resemble known luminous blue variable eruptions. The evolved Wolf-Rayet star could either result from the evolution of a very massive star or be the more evolved member of a massive binary system. We also suggest that there are a number of arguments in favour of a Type Ibn classification for the historical SN 1885A (S-Andromedae), previously considered as an anomalous Type la event with some resemblance to SN 1991bg.

Massive stars exploding in a He-rich circumstellar medium - II. The transitional case of SN 2005la

We present photometric and spectroscopic data of the peculiar SN 2005la, an object which shows an optical light curve with some luminosity fluctuations and spectra with comparably strong narrow hydrogen and helium lines, probably of circumstellar nature. The increasing full width at half-maximum velocity of these lines is indicative of an acceleration of the circumstellar material. SN 2005la exhibits hybrid properties, sharing some similarities with both Type IIn supernovae and 2006jc-like (Type Ibn) events. We propose that the progenitor of SN 2005la was a very young Wolf-Rayet (WN-type) star which experienced mass ejection episodes shortly before core collapse.