Long-term high-level exercise promotes muscle reinnervation with age.

The histologic features of aging muscle suggest that denervation contributes to atrophy, that immobility accelerates the process, and that routine exercise may protect against loss of motor units and muscle tissue. Here, we compared muscle biopsies from sedentary and physically active seniors and found that seniors with a long history of high-level recreational activity up to the time of muscle biopsy had 1) lower loss of muscle strength versus young men (32% loss in physically active vs 51% loss in sedentary seniors); 2) fewer small angulated (denervated) myofibers; 3) a higher percentage of fiber-type groups (reinnervated muscle fibers) that were almost exclusive of the slow type; and 4) sparse normal-size muscle fibers coexpressing fast and slow myosin heavy chains, which is not compatible with exercise-driven muscle-type transformation. The biopsies from the old physically active seniors varied from sparse fiber-type groupings to almost fully transformed muscle, suggesting that coexpressing fibers appear to fill gaps. Altogether, the data show that long-term physical activity promotes reinnervation of muscle fibers and suggest that decades of high-level exercise allow the body to adapt to age-related denervation by saving otherwise lost muscle fibers through selective recruitment to slow motor units. These effects on size and structure of myofibers may delay functional decline in late aging

Isotropic contact patterning to improve reproducibility in organic thin-film transistors

A novel approach for improving reproducibility of Organic Field-Effect Transistors electrical performances is proposed. The introduction of isotropic features in the layout of source and drain electrodes is employed to minimize the impact of randomly-distributed crystalline domains in the organic semiconductor film on the reproducibility of basic electrical parameters, such as threshold voltage and charge carrier mobility. A significant reduction of the standard deviation of these parameters is reported over a statistically-relevant set of devices with drop-casted semiconductor, if compared with results obtained in a standard, interdigitated transistor structure. A correlation between electrodes patterning and proposed result is demonstrated by deepening the analysis with the contribution of meniscus-assisted semiconductor printing, in order to precisely control the growth direction of crystals

Optimization of organic field-effect transistor-based mechanical sensors to anisotropic and isotropic deformation detection for wearable and e-skin applications

Flexible electronics represent a viable technology for the development of innovative mechanical sensors. This paper reports a detailed study of electro-mechanical performances of Organic Field-Effect Transistor-based sensor, investigating the role of source-drain electrodes layout in combination with organic semiconductor morphology obtained by different patterning methods. Two different sensor structures, with interdigitated and spiral-shaped source and drain electrodes, are employed together with solution-processed organic semiconductors deposited by drop-casting or patterned by means of meniscus-guided printing. This technique allows the orientation of crystalline domains to specific directions, and was employed to provide anisotropic or isotropic semiconductor patterns onto the transistor’s channel area. The different device configurations are tested as strain gauges and tactile sensors, by imposing anisotropic surface strain or complex deformations by means of custom-made, 3D-printed indenters. A wise choice of device structure and semiconductor patterning allows optimizing sensing performances as a response to specific deformations: interdigitated devices with crystalline domains aligned along the channel length direction are ideal strain gauges, while sensors with spiral-shaped electrodes in combination with isotropic semiconductor patterning are preferential for reproducing the sense of touch, which deals with the transduction of more complex deformation patterns. These results pave the way to the development of innovative sensors in the field of flexible bioengineering, in particular for the development of wearable and e-skin applications for joint motion monitoring and tactile sensing

The Messale Rosselli : Scientific investigation on an outstanding 14th century illuminated manuscript from Avignon

The manuscript D.I.21 kept at Biblioteca Nazionale Universitaria in Torino, better known as Messale Rosselli, is one of the richest fully illustrated missals surviving from the mid-14th century. It was produced in Avignon for the Aragonese Cardinal Nicolas Rossell (1314–1362) but after the patron's death, it passed from hand to hand until it reached its final destination in Torino. The Messale Rosselli has recently been the object of a thorough interdisciplinary study, involving full characterisation of the colourants with non-invasive techniques (FORS, fluorimetry, XRF spectrometry, optical microscopy, IR photography). The full set of colourants was identified, highlighting the systematic use of precious pigments such as lapis lazuli, cinnabar and gold, a feature reinforcing the symbolic value of the manuscript; in addition, less valuable but interesting dyes such as brazilwood and folium were also identified, used either pure or in a mixture with pigments in order to obtain a wide range of hues. The palettes used by the various artists have been evaluated according to the availability of raw materials in the geographic area around Avignon, finding that most of the colourants could be at easy disposal of the artists. Information has also been obtained concerning the preparation of the parchment. The systematic measurement of the width of folios allowed hypothesising the number of the animals slaughtered to produce parchment, and the way of using skins. XRF analysis on the folios suggested that different preparations were used. Finally, eZooMS, a non-invasive technique able to provide information on the animal species from which parchment was produced, evidenced that calf and goat, but not sheep, were used to produce the parchment of the Messale Rosselli