The Effect of 2 MHz Ultrasound on Intramuscular Temperature at 1.5, 2.5, and 3 cm Depths

The research objective was to determine the increase in intramuscular temperature of 2 MHz therapeutic ultrasound at 1.5, 2.5, and 3 cm depths after a 20 minute treatment at 1.0 W/cm2. A two-factor ANOVA experimental design guided this study. Three thermocouples were inserted into the medial gastrocnemius of twenty participants at all 3 depths. The ultrasound parameter settings consisted of: 2 MHz, continuous, 1.0 W/cm2. The mean intramuscular temperature increase at 20 minutes was the greatest at the 1.5 cm depth (5.22°C ± 1.25°C), then the 2.5 cm depth (3.59°C ± 1.61°C), then the 3 cm depth (2.75°C ± 1.48°C). Significant differences were found in the increase of intramuscular temperature of 2 MHz therapeutic ultrasound at all 3 depths, particularly at the 1.5 cm depth. Treatment goals and the type of machine need to be taken into account when delivering an ultrasound treatment in order for it to be effective

Soft-part preservation in a bivalved arthropod from the Late Ordovician of Wales

A new component of the Early Palaeozoic arthropod fauna is described from a monospecific accumulate of carapaces in a Late Ordovician (Katian) hemipelagic mudstone from the Cardigan district of southwest Wales (UK). Its non-biomineralized carapace is preserved as a carbonaceous residue, as is more labile anatomy (soft-parts) including the inner lamella and sub-ovate structures near its antero-dorsal margin, which we interpret to be putative eyes. The depositional context and associated fauna indicate that the arthropods inhabited an area of deep water and high primary productivity above a pronounced submarine topography. The preserved density of carapaces suggests the arthropods may have congregated into shoals or been transported post-mortem into depressions which acted as detritus traps. The accumulate provides a rare example of soft-part preservation in hemipelagic mudstones and highlights the role of organic material as a locus for authigenic mineralization during metamorphism