Optimal recording electrode placement for radial motor nerve conduction study using extensor indicis muscle: Cadaver and electrophysiological studies.

INTRODUCTION/AIMS: The aim of this study was to determine the optimal combination of active (E1) and reference (E2) recording electrode placements for the radial motor nerve conduction study recording over the extensor indicis muscle using surface electrodes. METHODS: Thirty-six upper limbs from 18 fresh frozen cadavers were dissected to determine the midpoint of the extensor indicis muscle. Radial nerve conduction study was performed in 112 arms of 56 healthy subjects. Six combinations of three E1 and two E2 sites were studied. The stimulation site was 8 cm proximal to the E1 electrode. RESULTS: The optimal combination of placement sites for the E1 and E2 electrodes to provide the largest amplitude is E1 electrode at the distal 1/4 point of the forearm length and E2 electrode at the extensor indicis tendon point in the wrist. DISCUSSION: Optimal recording electrode placement may increase the accuracy and reproducibility of radial motor nerve conduction studies.

Is Sensible Heat Flux Useful for the Assessment of Thermal Vulnerability in Seoul (Korea)?

Climate change has led to increases in global temperatures, raising concerns regarding the threat of lethal heat waves and deterioration of the thermal environment. In the present study, we adopted two methods for spatial modelling of the thermal environment based on sensible heat and temperature. A vulnerability map reflecting daytime temperature was derived to plot thermal vulnerability based on sensible heat and climate change exposure factors. The correlation (0.73) between spatial distribution of sensible heat vulnerability and mortality rate was significantly greater than that (0.30) between the spatial distribution of temperature vulnerability and mortality rate. These findings indicate that deriving thermally vulnerable areas based on sensible heat are more objective than thermally vulnerable areas based on existing temperatures. Our findings support the notion that the distribution of sensible heat vulnerability at the community level is useful for evaluating the thermal environment in specific neighbourhoods. Thus, our results may aid in establishing spatial planning standards to improve environmental sustainability in a metropolitan community.