Validation of a graphic test to quantitatively assess the dominant hand dexterity

Dexterity dysfunction is a key feature of disability in many neurological and non-neurological diseases. The Nine-Hole Peg Test (NHPT) is the most used test to assess hand dexterity in clinical practice but presents limitations. A new graphic test to enhance objective evaluation of the of the dominant hand dexterity is proposed. The task consists in drawing a continuous line in paths composed by a part with multiple orthogonal changes of direction (‘meander’), and a second part derived from the Archimedean spiral (‘spiral’). The test was validated in 200 healthy controls and 93 neurological patients. 48 patients performed also the NHPT. Several parameters were analyzed, among which total time, total length, number of touches and number of crossings. Healthy subjects display statistically significant differences with respect to pathological subjects in the case of total time, number of touches, and number of crossings (p<0.001), but not in the case of total length (p = 0.27) needed to complete the second sheet. Moreover, healthy controls display a learning effect, the time needed to complete the second sheet was significantly lower than for the first sheet (p<0.001), and an inverse correlation with age was observed (r = 0.56, p<0.001). The comparison between the NHPT and the new test showed a strong positive correlation (r = 0.71, p<0.001) whereas touches and crossing a weak positive one (r = 0.35, p = 0.01). The new test distinguishes between a slow but precise performance and a fast but imprecise performance, thus providing additional information with respect to NHPT

The rubber hand illusion in microgravity and water immersion

Our body has evolved in terrestrial gravity and altered gravitational conditions may affect the sense of body ownership (SBO). By means of the rubber hand illusion (RHI), we investigated the SBO during water immersion and parabolic flights, where unconventional gravity is experienced. Our results show that unconventional gravity conditions remodulate the relative weights of visual, proprioceptive, and vestibular inputs favoring vision, thus inducing an increased RHI susceptibility

Hydrogen production at high Faradaic efficiency by a bio-electrode based on TiO2 adsorption of a new [FeFe]-hydrogenase from Clostridium perfringens

© 2015 Elsevier B.V. The [FeFe]-hydrogenase CpHydA from Clostridium perfringens was immobilized by adsorption on anatase TiO2 electrodes for clean hydrogen production. The immobilized enzyme proved to perform direct electron transfer to and from the electrode surface and catalyses both H2 oxidation (H2 uptake) and H2 production (H2 evolution) with a current density for H2 evolution of about 2mAcm-1. The TiO2/CpHydA bioelectrode remained active for several days upon storage and when a reducing potential was set, H2 evolution occurred with a mean Faradaic efficiency of 98%. The high turnover frequency of H2 production and the tight coupling of electron transfer, resulting in a Faradaic efficiency close to 100%, support the exploitation of the novel TiO2/CpHydA stationary electrode as a powerful device for H2 production