Robot-assisted training is a widely used technique to promote motor re-learning on post-stroke patients that suffer from motor impairment. While it is commonly accepted that robot-based therapies are ...potentially helpful, strong insights about their efficacy are still lacking. The motor re-learning process may act on muscular synergies, which are groups of co-activating muscles that, being controlled as a synergic group, allow simplifying the problem of motor control. In fact, by coordinating a reduced amount of neural signals, complex motor patterns can be elicited. This paper aims at analyzing the effects of robot assistance during 3D-reaching movements in the framework of muscular synergies. 5 healthy people and 3 neurological patients performed free and robot-assisted reaching movements at 2 different speeds (slow and quasi-physiological). EMG recordings were used to extract muscular synergies. Results indicate that the interaction with the robot very slightly alters healthy people patterns but, on the contrary, it may promote the emergency of physiological-like synergies on neurological patients.
In the last decade, great attention has been given to hydrothermal carbonization (HTC) as a suitable process for residual biomass valorization, able to convert organic waste into useful materials or ...energy carriers. However, the involved conversion reactions that biomass components undergo are influenced by the characteristics of the treated residue along with the HTC process conditions, particularly in terms of temperature and holding time. In this paper, the potential valorization of hemp digestate via HTC was investigated. The study was aimed at evaluating the effect of reaction temperature and holding time on the yield and composition of produced hydrochar and on the process water characteristics. Three temperatures (180, 200, and 220 °C) were investigated along with three holding times (1, 3, and 6 h) and the obtained solid and liquid phases were characterized. Results show that the investigated operating parameters affect both the solid yield and the hydrochar and process water composition. By increasing process severity conditions through an increase in temperature and/or holding time, a drop in solid yield (89–60 wt%) and an increase in carbon content (+ 15– + 30%) and energy content (up to + 22%) were achieved for the produced hydrochar compared to the feedstock, which showed suitable properties in view of its use as a fuel. Process water characteristics suggest a potential valorization in terms of nutrient recovery or biogas production by anaerobic digestion, while the feasibility of an aerobic treatment should be carefully evaluated.
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The influence of drug concentration and vesicle composition on the (trans)dermal delivery of tretinoin (TRA) was studied. To this purpose tretinoin was incorporated at different concentrations in ...unilamellar liposomes (UVs) prepared by sonication using phospholipids with different transition temperature (Tc): hydrogenated soy phosphatidylcholine (Tc = 51°C) or dipalmitoylphosphatidylcholine (Tc = 41°C). Vesicle dispersions were characterized in terms of morphology, size distribution and incorporation efficiency by using respectively optical and polarized light microscopy, transmission electron microscopy, dynamic laser light scattering, and HPLC. The effect of the vesicular incorporation of tretinoin at different molar ratios was investigated by zeta potential measurements and differential scanning calorimetry analysis. These analyses indicated that tretinoin principally interacts with the lipid groups until bilayer saturation. At higher concentration the ionized drug interacts with the polar head. Interactions between new-born pig skin and vesicle containing different amount of tretinoin were evaluated in vitro using Franz cells. The results obtained confirmed that liposomes saturated with TRA (molar fraction = 0.3) are capable of significantly promoting drug accumulation in the pig skin and that (trans)cutaneous delivery is strongly dependent on vesicular stability on the skin.
Physico‐chemical equilibria that influence oxide powders' precipitation from an aqueous solution can be substantially altered when the process is carried out in a microemulsion system. To obtain ...nanosized MnFe2O4 and gain information about the physico‐chemical characteristics of products, Mn2+ and Fe3+ metal ions were induced to precipitate in a toluene/water/sodium dodecylbenzenesulfonate microemulsion system. Portions of the precipitated powder were differently treated, both in solution and in the solid state, and the role of restricted aqueous domains in the obtained materials was investigated. X‐ray diffraction profile‐fitting methods and chemical analysis were applied to characterize the powder particles. Samples obtained from the selected microemulsion were identified as nanosized mixed hydroxide compounds. A low metal content and a limited matter exchange among aqueous nanodroplets appear to inhibit hydroxide to oxide transformation inside the selected micellar system. A calcination process of precipitated powder was required to obtain a manganese ferrite compound.
Ball Milling technique has been used to prepare for the first time Vitis Vinifera extract-silica nanocomposites (VV-SiO
NCs), which combine the pharmacological effects of the extract with the ...effectiveness of silica as drug delivery system and active component in the treatment of wound healing. Different contents (1.0, 9.0 and 33.0 wt%) of Vitis Vinifera ethanolic extract were loaded into the silica matrix by grinding the extract with fumed silica using a planetary mill apparatus. The effect of the starting mixture composition and milling time on the final products was examined. The efficiency of the milling process was studied by X-ray Powder Diffraction, Nuclear Magnetic Resonance, and Infrared Spectroscopy, indicating that the natural extract was not affected by the increasing of the milling time. The successful loading of the extract was demonstrated by Nitrogen adsorption/desorption measurements, which showed a decrease in the SSA and pore volume of the silica with the increasing of the extract amount. Morphology of the nanocomposites, investigated by Scanning Electron Microscopy, showed an increased agglomeration in the nanocomposites with the increment of the VV extract amount. Studies on the total phenol quantification and antioxidant activity of the natural extract before and after incorporation in the silica matrix were also carried out. The obtained results indicate that the milling process does not alter the VV extract components, which result to be embedded in the silica matrix. An increase of the antioxidant activity with the increment of the extract amount in the nanocomposites, up to values comparable to the pure VV extract, was also observed.
A method is presented for surface modification of 3D metallic components, to generate micron-sized features to improve drag and surface interaction with viscous fluids. The technique relays in the ...selective consolidation of pre-placed powder, directly on the surface of the component, to produce micro-cladding tracks under 50 microns in width. A single mode fibre laser is scanned at high speed on the powder to provide the desired geometry. The requirements and limits of the technique are studied, regarding the laser source, optical setup and powder preplacing methodology, as well as practical aspects for its implementation and some applications.
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