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Supplemental material, sj-docx-1-pam-10.1177_27536386231162609 for Factors associated with pain reporting and severity of pain in the prehospital setting by Rory J Quinn, Siobhan Masterson, David Willis, David Hennelly, Conor Deasy and Cathal O'Donnell in Paramedicine

Supplemental material, sj-docx-1-pam-10.1177_27536386231162609 for Factors associated with pain reporting and severity of pain in the prehospital setting by Rory J Quinn, Siobhan Masterson, David Willis, David Hennelly, Conor Deasy and Cathal O'Donnell in Paramedicine

Hydrodynamics

Chirp sub-bottom profilers produce high-resolution images of the near-surface. An attribute of the sea-bed reflection in chirp data are fluctuations in polarity between adjacent traces. Two models are proposed and presented to explain this: the first incorporates changes in an acoustic impedance gradient at the sea bed; the second uses changes in the thickness of the uppermost sediment layer. Mixing of adjacent traces produces a consistent polarity for the sea-bed reflector. Reflection coefficients are calculated, using amplitude information derived from single-traces, and polarity information from trace mixing, with application to a marine archaeological case study. The reflection coefficient calculated for the top of a buried 18th century wooden wreck is -0.26.

Buried wooden artefacts can be readily imaged by Chirp-sourced reflection seismology. Compressional wave velocity parallel to the wood grain (VL) is consistently faster than that across-grain (VR and VT). Theoretical and experimental predictions of reflection coefficients (KR) calculated for wood buried in unconsolidated marine sediments are typically large and negative (KR = +0.27 to -0.79; KRoak = 0.03 to -0.64). Variations in KR are dependent upon the burial-sediment, wood species and structural coherency of the artefact.Synthetic modelling demonstrates that small changes in the seafloor impedance profile causes random switches in the polarity of the Chirp pulse. Reflection coefficients are calculated from Chirp sub-bottom data using amplitude-time relationships and polarity information derived from trace-mixing. Calculations from Chirp data acquired over a partially buried 17th Century oak-wreck provide an average KR of -0.26, in agreement with the predicted range.A pseudo 3-dimensional Chirp survey of the excavated Mary Rose wreck site (East Solent, UK) identified two brightspot anomalies, buried to a depth of 4-5 m, trending east-west adjacent to the western margin of the excavation hole. These anomalous reflectors are interpreted as infilled palaeo-scour features associated with the wrecking and subsequent degradation of the Mary Rose. Fill material comprises wreck fragments and coarse sediment sourced from the ship's ballast. Longitudinal scour features were previously unrecognised on the site, and represent the first time such palaeo-scour marks have been recognised in the sedimentary record.Integrated Chirp and side-scan sonar surveys of the Invincible site (East Solent, UK) demonstrate the capability of high-resolution acoustic techniques to: identify the extent and coherency of semi-exposed wrecks, determine the wrecking history of a site and act as an effective management tool. The distribution of wreck material is primarily controlled by storm-associated wave action, depositing the bulk of fragmented wreck-structure to the north and north-east of the in situ port side. Evidence suggests that current site stability is controlled by a combination of tidally induced currents and anthropogenic activity.