Formation of the X-ray line emission spectrum of excimer laser-produced plasmas

Time- and space-integrated emission spectra measurements have been performed in plasma produced by 308 nm wavelength XeCl laser radiation (IL = (4–10)·1012 W/cm2, τ = 10 ns) and by 248 nm wavelength KrF laser pulse train radiation (IL = 5·1015 W/cm2, τ = 7 ps, 16 pulses in train) on CF2 plane target. Theoretical modelling of Lyman series and He-like ion resonance series of fluorine and its fit of experimental data show considerable differences in the absorption of laser radiation in the two plasmas

The development of arable cultivation in the south-east of England and its relationship with vegetation cover: A honeymoon period for biodiversity?

The onset of prehistoric farming brought unprecedented changes to landscapes and their biodiversity. Past biodiversity patterns are broadly understood for different parts of Europe, and demonstrate trajectories that have been linked to prehistoric and historic demographic transitions, and associated land-use practices. To our knowledge, this paper is the first attempt to directly link evidence of agricultural practice from the archaeological record to biodiversity patterns. Records of fossil pollen are used to estimate plant and landscape diversity patterns, and novel approaches are employed to analyse 1194 harmonised archaeobotanical samples (plant macrofossil remains) spanning the prehistoric and Roman periods, from southern England. We demonstrate changes in the use of crops and gathered edible plants and non-linear trends in cultivation practices. Whilst, overall, cereal production is characterised by ever larger and extensive regimes, different trajectories are evident for most of early prehistory, the Middle Iron Age and the Late Roman period. Comparisons with the Shannon diversity of fossil pollen records from the same region suggest a positive relationship between developing agricultural regimes and landscape scale biodiversity during the prehistoric period. The Roman period represents a tipping point in the relationship between expanding agriculture and pollen diversity, with declining pollen diversity evident in the records from the region

Internal accounting practices at Whitbread & Company c.1890-1925

This paper examines internal accounting practices at Whitbread & Company from c. 1890 to 1925. At this time, there was an increasing interest in cost accounting, but there is little detailed extant research on general internal accounting practices of firms. The brewing sector, we suggest, is a potentially fruitful realm to further our knowledge of this time. Drawing on the Whitbread brewery archival records, we chart the internal accounting practices of the company. Our findings reveal a stable set of accounting practices, focused mainly on bookkeeping, although the firm’s auditor produced some reports which may have been useful for management decision-making. We argue these practices were highly institutionalised, and seemingly resistant to external forces present in the company’s environment

Theorising terminology development: Frames from language acquisition and the philosophy of science

The manner in which our conceptualisation and practice of terminology development can be informed by processes of knowledge change in child language development and a paradigm shift in disciplines, has been relatively underexplored. As a result, insights into what appears to be fundamental processes of knowledge change have not been employed to reflect on terminology development, its dynamics, requirements and relationship to related fields. In this article, frames of knowledge change in child language development and the philosophy of science are used to examine terminology development as knowledge growth that is signalled lexico-semantically through a range of transformations: addition, deletion, redefinition and reorganisation. The analysis is shown to have implications for work procedures, expertise types, critique, and for the relationships between terminology development and translating

Consideration of metabolite efflux in radiolabelled choline kinetics

Hypoxia is a complex microenvironmental condition known to regulate choline kinase α (CHKA) activity and choline transport through transcription factor hypoxia-inducible factor-1α (HIF-1α) and, therefore may confound uptake of choline radiotracer [ 18F]fluoromethyl-[1,2- 2H4]-choline ([ 18 F]-D4-FCH). The aim of this study was to investigate how hypoxia affects choline radiotracer dynamics. Three underlying mechanisms by which hypoxia could potentially alter the uptake of the choline radiotracer, [ 18 F]-D4-FCH, were investigated: 18F-D4-FCH import, CHKA phosphorylation activity, and efflux of [18 F]-D4-FCH and its phosphorylated product [ 18F]-D4-FCHP. Effects of hypoxia on [18 F]-D4-FCH uptake were studied in CHKA-overexpressing cell lines of prostate cancer, PC-3, and breast cancer, MDA-MB-231 cells. Mechanisms of radiotracer efflux were assessed by cell uptake and immunofluorescence in vitro, and examined in vivo (N=24). Mathematical modelling methodology was further developed to verify efflux hypothesis using [18 F]-D4-FCH dynamic PET scans from non-small cell lung cancer (NSCLC) patients (N=17). We report a novel finding involving export of phosphorylated [18F]-D4-FCH, [18 F]-D4-FCHP, via HIF-1α-responsive efflux transporters including ABCB4 when HIF-1α level is augmented. This is supported by graphical analysis of human data with a compartmental model (M2T6k+k5) that accounts for efflux. Hypoxia/HIF-1α increases the efflux of phosphorylated radiolabelled choline species, thus supporting consideration of efflux in modelling of radiotracer dynamics