Vibrotactile Feedback During Physical Exercise: Perception of Vibrotactile Cues in Cycling.

The aim of this study was to investigate the perception of vibrotactile signals during physical exercise by comparing differences in recognition between stationary and cycling positions. The impact of physical exercise on the ability to perceive vibrotactile cues is unknown, whereas the recognition in stationary position has been shown previously. Vibrating elements were positioned at 3 locations on the thighs and spine of 9 athletes to apply various vibrotactile cues. Subjects performed at 0, 50, 70 and 90% of their maximal cycling power output and denoted the interpretation of the vibration signals on a touchscreen. The results show a similarity in correct recognition between stationary position and physical exercise for the thighs and spine (p>0.1) and demonstrate a decrease in response time for 70 and 90% levels of physical exercise compared to 0 and 50% (p<0.001). Furthermore, vibrotactile signals at the spine are noticed more accurately and more rapidly compared to the thighs (p<0.01). These results suggest that vibrotactile feedback also has potential in applications during physical exercise. The potential use of vibrotactile feedback can be in cycling for, among other, correcting the aerodynamic position. Applications in other sports and health-related domains are feasible as well.

First results of a quantitative study of DNA adducts of melphalan in the rat by isotope dilution mass spectrometry using capillary liquid chromatography coupled to electrospray tandem mass spectrometry.

Rats were intravenously injected with a single high dose (10 mg/kg) of the alkylating agent melphalan in order to study DNA-adduct formation. Quantitation of a dGuo-melphalan adduct was done by isotope dilution mass spectrometry using capillary liquid chromatography/mass spectrometry (LC/MS) and [15N5]-labeled dGuo-melphalan as internal standard. DNA-adduct levels were studied in bone marrow, liver and kidney. The instrumental detection limit of the method was determined to be 900 fg (S/N 3, pure standard). These first results clearly show a 10 times higher adduct level in bone marrow compared to kidney and a 6 times higher level compared to liver. More experiments will be necessary to gather more information on the pharmacokinetics of melphalan-DNA adducts under in vivo conditions.