Testing the cause of the Sphagnum austinii (Sull. ex Aust.) decline: Multiproxy evidence from a raised bog in Northern Ireland

We use a multiproxy palaeoecological dataset from Dead Island bog in Northern Ireland to examine the cause of the Sphagnum austinii (Sphagnum imbricatum) decline. The disappearance of this species from the peat record occurred just after the ‘AD 860’ tephra layer and is coeval with a rapid increase in bog surface wetness and increased mineral dust and charcoal abundance. Although it is difficult to identify one specific cause of the decline, the evidence for increased soil-derived dust is apparent and is supported by regional tephra-dated pollen diagrams that reveal extensive landscape changes due to agricultural intensification in early Medieval Ireland. As the decline of S. austinii occurred much later (~ AD 1860) in Fallahogy bog (~ 1.2 km away), we suggest that the decline of S. austinii at Dead Island was caused by a combination of fire and the deposition of soil-derived dust. We suggest that future studies should consider the use of multiple cores from each site to examine the within-site variability of the decline of S. austinii.

RAS testing of colorectal carcinoma—a guidance document from the Association of Clinical Pathologists Molecular Pathology and Diagnostics Group

Analysis of colorectal carcinoma (CRC) tissue for KRAS codon 12 or 13 mutations to guide use of anti-epidermal growth factor receptor (EGFR) therapy is now considered mandatory in the UK. The scope of this practice has been recently extended because of data indicating that NRAS mutations and additional KRAS mutations also predict for poor response to anti-EGFR therapy. The following document provides guidance on RAS (i.e., KRAS and NRAS) testing of CRC tissue in the setting of personalised medicine within the UK and particularly within the NHS. This guidance covers issues related to case selection, preanalytical aspects, analysis and interpretation of such RAS testing.

Testing numerical implementations of strong-field electrodynamics

We test current numerical implementations of laser-matter interactions by comparison with exact analytical results. Focusing on photon emission processes, it is found that the numerics accurately reproduce analytical emission spectra in all considered regimes, except for the harmonic structures often singled out as the most significant high-intensity (multiphoton) effects. We find that this discrepancy originates in the use of the locally constant field approximation.