Quality of low secure services in the UK: development and use of the Quality of Environment In Low Secure Services (QELS) checklist

Low secure services provide care for psychiatric patients whose risk cannot be safely managed in other settings. The physical environment in these units plays an important role in supporting recovery and risk management. We developed the Quality of Environment in Low secure Services (QELS) checklist to assess the quality of the physical environment of these services. Using recommendations from previously published standards we piloted a draft checklist with a weighted scoring system reflecting the views of patients and providers. The checklist showed good criterion validity and inter-rater reliability. Data collected from 33 low secure services showed considerable variation in the quality of the physical environment. The QELS checklist provides an accessible and reliable means for managers and clinicians to assess whether the quality of the physical environment of low secure units meets recommended standards and can be used to support efforts to improve the quality of care delivered by these services.     

An Impact Velocity Device Design for Blood Spatter Pattern Generation with Considerations for High‐Speed Video Analysis,

A mechanical device that uses gravitational and spring compression forces to create spatter patterns of known impact velocities is presented and discussed. The custom‐made device uses either two or four springs (k₁ = 267.8 N/m, k₂ = 535.5 N/m) in parallel to create seventeen reproducible impact velocities between 2.1 and 4.0 m/s. The impactor is held at several known spring extensions using an electromagnet. Trigger inputs to the high‐speed video camera allow the user to control the magnet's release while capturing video footage simultaneously. A polycarbonate base is used to allow for simultaneous monitoring of the side and bottom views of the impact event. Twenty‐four patterns were created across the impact velocity range and analyzed using HemoSpat. Area of origin estimations fell within an acceptable range (ΔX_av = ?5.5 ± 1.9 cm, ΔY_av = ?2.6 ± 2.8 cm, ΔZ_av = +5.5 ± 3.8 cm), supporting distribution analysis for the use in research or bloodstain pattern training. This work provides a framework for those interested in developing a robust impact device.     

Transcellular and extracellular impedances of the intact abdomen in putrefying rat cadavers

Total (Zt) and extracellular (Ze) abdominal impedances of putrefying rat cadavers, stored at 18.0±0.7°C, were measured at 50 kHz and at 1 kHz, respectively, during the first 7 days of death. Transcellular impedance was calculated from the measured values of Zt and Ze. Total impedance and Ze increased during the first day, and then decreased with increasing postmortem interval, while Zi remained unchanged during the first 3 days before increasing more than 4-fold between 3 and 7 days postmortem. These changes are consistent with net gain of electrolyte by the extracellular fluids and with degeneration of cell membranes which occur postmortem. It is concluded that, during putrefaction, Ze is a potentially more useful index of postmortem interval than Zt or Zi, and that measurement of total abdominal impedance at 50 kHz, rather than at 10 kHz, markedly improves the precision and accuracy of impedance measurement.