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The design of myocontrolled devices faces particular challenges in children with dyskinetic cerebral palsy because the electromyographic signal for control contains both voluntary and involuntary components. We hypothesized that voluntary and involuntary components of movements would be uncorrelated and thus detectable as different synergistic patterns of muscle activity, and that removal of the involuntary components would improve online EMG-based control. Therefore, we performed a synergy-based decomposition of EMG-guided movements, and evaluated which components were most controllable using a Fitts Law task. Similarly, we also tested which muscles were most controllable. We then tested whether removing the uncontrollable components or muscles improved overall function in terms of movement time, success rate, and throughput. We found that removal of less controllable components or muscles did not improve EMG control performance, and in many cases worsened performance. These results suggest that abnormal movement in dyskinetic CP is consistent with a pervasive distortion of voluntary movement rather than a superposition of separable voluntary and involuntary components of movement.

Hydrogen is a versatile energy carrier and storage medium that may be employed in a variety of applications. It may be produced using different processes. In this work, process simulation is used to obtain material and energy balances for each process investigated, as well as for the evaluation of capital and maintenance costs. Process simulation outcomes are then used to estimate three key performance indicators focusing on sustainability issues: the energy return of energy invested, the levelized cost of hydrogen and the life cycle assessment. We compared several hydrogen generation processes, each denoted by a unique colour code: (i) green hydrogen, produced by electrolysis of water using electricity from renewable sources, (ii) grid hydrogen, produced by electrolysis using grid electricity, (iii) grey hydrogen, produced from natural gas using steam reforming and (iv) blue hydrogen, like grey one, but coupled with carbon capture and storage. In conclusion, the most sustainable hydrogen production method is the green hydrogen, produced by water electrolysis.

Microalgal biomass has been considered as a possible alternative source of carbohydrates and lipids in fermentative/reactional processes, called third generation of biofuels. Carbohydrates from microalgae are mostly composed by glucose and some pentose-derived polymers that must be hydrolyzed to be efficiently used. When enzymatic hydrolysis is applied a pretreatment is required. Sonication/ultrasonication is one of the most promising methods, and in this paper the influence of pretreatment time, sonication intensity and biomass concentration was validated, and the energy consumed in the process compared as well. Sonication intensity had the major role on the enzymatic accessibility. Pretreatment time can be used to decrease hydrolysis time. More than 90% of hydrolysis efficiency was reached when higher amplitude (sonication intensity) and pretreatment time were used. The applied energy influenced indirectly the hydrolysis process. The best saccharification/energy relation was reached when 50% of amplitude for 25 min was applied, obtaining 91% of hydrolysis yield and spending 2.4 MJ/kg of dry biomass. Keywords: Microalgae, Ethanol, Fermentation, Amylase, Cellulase, Sonication

The utilization of real producer gases such as raw biogas or gasified wood for chemical looping hydrogen production implies the introduction of harmful contaminants into the process. Hydrogen sulfide represents one of the most challenging trace gases in the reformer steam iron cycle. The aim of the present work was an in-depth investigation of steam reforming with pure methane and synthetic biogas contaminated with selective concentrations of 1, 5 and 10 ppm of hydrogen sulfide. To validate the experimental data, the fixed-bed reactor system was modeled as one-dimensional pseudo-homogeneous plug flow reactor by an adapted Maxted model. In a preliminary thermodynamic study, the dry equilibrium composition was determined within a deviation of 4% for steam methane reforming (SMR) and 2% for synthetic biogas reforming compared to the experimental results. The impact of hydrogen sulfide on the reactivity of the catalyst was characterized by the residual methane conversion. The deactivation rate and extent is directly proportional to the concentration of H _2 S, as higher hydrogen sulfide concentrations lead to a faster deactivation and lower residual methane conversion. A comparison of the methane conversion as a function of sulfur coverage between experimental and simulated data showed good agreement. The predicted results are within

Changes in muscle shape could play an important role during contraction allowing to circumvent some limits imposed by the fascicle force–velocity (F–V) and power–velocity (P–V) relationships. Indeed, during low-force high-velocity contractions, muscle belly shortening velocity could exceed muscle fascicles shortening velocity, allowing the muscles to operate at higher F–V and P–V potentials (i.e., at a higher fraction of maximal force/power in accordance to the F–V and P–V relationships). By using an ultrafast ultrasound, we investigated the role of muscle shape changes (vastus lateralis) in determining belly gearing (muscle belly velocity/fascicle velocity) and the explosive torque during explosive dynamic contractions (EDC) at angular accelerations ranging from 1000 to 4000°.s–2. By means of ultrasound and dynamometric data, the F–V and P–V relationships both for fascicles and for the muscle belly were assessed. During EDC, fascicle velocity, belly velocity, belly gearing, and knee extensors torque data were analysed from 0 to 150 ms after torque onset; the fascicles and belly F–V and P–V potentials were thus calculated for each EDC. Absolute torque decreased as a function of angular acceleration (from 80 to 71 Nm, for EDC at 1000 and 4000°.s–1, respectively), whereas fascicle velocity and belly velocity increased with angular acceleration (P < 0.001). Belly gearing increased from 1.11 to 1.23 (or EDC at 1000 and 4000°.s–1, respectively) and was positively corelated with the changes in muscle thickness and pennation angle (the changes in latter two equally contributing to belly gearing changes). For the same amount of muscle’s mechanical output (force or power), the fascicles operated at higher F–V and P–V potential than the muscle belly (e.g., P–V potential from 0.70 to 0.56 for fascicles and from 0.65 to 0.41 for the muscle belly, respectively). The present results experimentally demonstrate that belly gearing could play an important role during explosive contractions, accommodating the largest part of changes in contraction velocity and allowing the fascicle to operate at higher F–V and P–V potentials.

The present study investigated whether a difference exists in reactive and proactive control for sport considered open or closed skills dominated. Sixteen young (11-12 years) athletes (eight soccer players and eight swimmers) were asked to be engaged into two games competitions that required either a reactive and a proactive type of control. By means of kinematic (i.e. movement time and duration) and dynamic analysis through the force platform (i.e. Anticipatory Postural Adjustments, APAs), we evaluated the level of ability and stability in reacting and anticipating actions. Results indicated that soccer players outperformed swimmers by showing higher stability and a smaller number of falls during the competition where proactive control was mainly required. Soccer players were able to reach that result by anticipating actions through well-modulated APAs. On the contrary, during the competition where reactive control was mainly required, performances were comparable between groups. Therefore, the development of specific action control is already established at 11-12 years of age and is enhanced by the training specificity.

The design of myocontrolled devices faces particular challenges in children with dyskinetic cerebral palsy because the electromyographic signal for control contains both voluntary and involuntary components. We hypothesized that voluntary and involuntary components of movements would be uncorrelated and thus detectable as different synergistic patterns of muscle activity, and that removal of the involuntary components would improve online EMG-based control. Therefore, we performed a synergy-based decomposition of EMG-guided movements, and evaluated which components were most controllable using a Fitts' Law task. Similarly, we also tested which muscles were most controllable. We then tested whether removing the uncontrollable components or muscles improved overall function in terms of movement time, success rate, and throughput. We found that removal of less controllable components or muscles did not improve EMG control performance, and in many cases worsened performance. These results suggest that abnormal movement in dyskinetic CP is consistent with a pervasive distortion of voluntary movement rather than a superposition of separable voluntary and involuntary components of movement.

Modeling the growth of photosynthetic organisms is challenging, due to the complex role of light, which can be limiting because of self-shading, or photoinhibiting in the case of high intensities. A case of particular interest is represented by nitrogen-fixing cyanobacteria, whose growth is controlled not only by the light intensity, but also by the availability of atmospheric nitrogen in the liquid medium. The determination of the maximum specific growth rate is often affected by many variables that, in batch growth systems, may change significantly. On the other hand, in a continuous system, once the steady state is reached the values of all the process variables remain constant, including the biomass concentration and the specific light supply rate. In this work, the diazotrophic cyanobacterium Anabaena PCC 7122 was cultivated in continuous photobioreactors, to investigate the role of nitrogen, light and residence time on growth kinetics, and to retrieve the value of the maximum specific growth rate of this organism. In addition, the kinetic parameters for temperature and the half saturation constant for nitrogen (3 mg L−1) were measured by respirometric tests. Based on the results of continuous experiments, the specific maintenance rate was found to depend on the light intensity supplied to the reactor, ranging between 0.5 and 0.8 d−1. All these parameters were used to develop a kinetic model able to describe the biomass growth in autotrophic conditions. The maximum specific growth rate could hence be determined by applying the kinetic model in the material balances of the continuous photobioreactor, and resulted equal to 8.22 ± 0.69 d−1.

Patients with Parkinson’s disease (PD) show typical gait asymmetries. These peculiar motor impairments are exacerbated by added cognitive and/or mechanical loading. However, there is scarce literature that chains these two stimuli. The aim of this study was to investigate the combined effects of a dual task (cognitive task) and turning (mechanical task) on the spatiotemporal parameters in mild to moderate PD. Participants (nine patients with PD and nine controls (CRs)) were evaluated while walking at their self-selected pace without a secondary task (single task), and while repeating the days of the week backwards (dual task) along a straight direction and a 60° and 120° turn. As speculated, in single tasking, PD patients preferred to walk with a shorter stride length (p < 0.05) but similar timing parameters, compared to the CR group; in dual tasking, both groups walked slower with shorter strides. As the turn angle increased, the speed will be reduced (p < 0.001), whereas the ground–foot contact will become greater (p < 0.001) in all the participants. We showed that the combination of a simple cognitive task and a mechanical task (especially at larger angles) could represent an important training stimulus in PD at the early stages of the pathology.

In this study, the feasibility of integrating microalgae cultivation in a biogas production process that treats the organic fraction of municipal solid waste (OFMSW) was investigated. In particular, the biomass growth performances in the liquid fraction of the digestate, characterized by high ammonia concentrations and turbidity, were assessed together with the nutrient removal efficiency. Preliminary laboratory-scale experiments were first carried out in photobioreactors operating in a continuous mode (Continuous-flow Stirred-Tank Reactor, CSTR), to gain preliminary data aimed at aiding the subsequent scaling up to a pilot scale facility. An outdoor experimental campaign, operated from July to October 2019, was then performed in a pilot scale raceway pond (4.5 m2), located in Arzignano (VI), Italy, to assess the performances under real environmental conditions. The results show that microalgae could grow well in this complex substrate, although dilution was necessary to enhance light penetration in the culture. In outdoor conditions, nitrification by autotrophic bacteria appeared to be significant, while the photosynthetic nitrogen removal was around 12% with respect to the inlet. On the other hand, phosphorus was almost completely removed from the medium under all the conditions tested, and a biomass production between 2–7 g m−2 d−1 was obtained.

Leachate from landfill is one of the most relevant unsolved environmental issues, in particular related to the high ammonia content. In this work, the possibility of treating this waste stream with a combined approach that includes both physical and biological treatment was assessed. The process is composed by a first evaporation/condensation step in an innovative industrial technology (WastWa) developed by Solwa SrL, that allows separating an aqueous stream in which about half of the water volume and most of the ammonia are recovered, and a concentrated leachate stream. The ammonia-rich water stream can be then sent to a microalgal cultivation step for N removal, while the concentrated waste can either be partially used to provide micronutrients for microalgal growth or delivered to phytodepuration. The feasibility of the process was tested at lab scale by carrying out both batch and continuous experiments with Acutodesmus obliquus, a microalgal species isolated from a pond containing pretreated leachate from an urban landfill located in Lazio (Italy). This strain was cultivated both in untreated leachate and in the aqueous outlet stream of the WastWa unit. A simulation model of the microalgal growth process was implemented in Aspen Plus, keeping into account the chemical equilibrium and ionic speciation of the nutrients in solution as well as the pH. The model was able to reproduce well the experimental data, and can therefore be a useful tool to evaluate the feasibility of the proposed process at large-scale.

In this work, the development and simulation of a new coal gasification process with indirect heat supply is performed. In this way, the need of pure oxygen production as in a conventional gasification process is avoided. The feasibility and energetic self-sufficiency of the proposed processes are addressed. To avoid the need of Air Separation Unit, the heat required by gasification reactions is supplied by the combustion flue gases, and transferred to the reacting mixture through a bayonet heat exchanger installed inside the gasifier. Two alternatives for the flue gas generation have been investigated and compared. The proposed processes are modeled using chemical kinetics validated on experimental gasification data by means of a standard process simulator (Aspen PlusTM), integrated with a spreadsheet for the modeling of a special type of heat exchanger. Simulation results are presented and discussed for proposed integrated process schemes. It is shown that they do not need external energy supply and ensure overall efficiencies comparable to conventional processes while producing syngas with lower content of carbon dioxide.

The purpose of this study was to investigate the rear knee angle range in the set position that allows sprinters to reach greater propulsion on the rear block during the sprint start. Eleven university-track team sprinters performed the sprint start using three rear knee angle conditions: 90°, 115° and 135°. A motion capture system consisting of 8 digital cameras (250 Hz) was used to record kinematic parameters at the starting block phase and the acceleration phase. The following variables were considered: horizontal velocity of the centre of mass (COM), COM height, block time, pushing time on the rear block, percentage of pushing time on the rear block, force impulse, push-off angle and length of the first two strides. The main results show that first, horizontal block velocity is significantly greater at 90° vs 115° and 135° rear knee angle (p

Background: Eruca sativa Mill. is a good source of glucosinolates (GLS), phenolic compounds and unsaturated fatty acids, being a valuable material for the production of functional-foods or nutraceutical ingredients. Extraction by supercritical CO2 (SCO2) can be used and the limitations due to the apolar nature of CO2 can be overcome using co-solvents. In this paper different cosolvents and conditions were used for SCO2 extraction and the composition of the obtained extracts was studied by LC-MS. Results: Water resulted the ideal co-solvent, allowing the extraction of glucosinolates in comparable amounts to the classical procedure with boiling water, as it can be carried out at mild temperatures (45 °C vs. >100 °C). Increasing the pressure improved the GLS extraction. On the other hand polyphenol extraction under the studied conditions was not influenced by pressure and temperature variations. The in vitro antioxidant effect of the obtained extracts was also measured, showing significant activity in the DPPH and FC tests. Conclusions: The GLS, flavonoids and lipids composition of the obtained extracts was studied, showing the presence of numerous antioxidant constituents useful for nutraceutical applications. The extraction method using SCO2 and water as co-solvent presents advantages in terms of safety because these solvents are generally recognised as safe. Water as cosolvent at 8% resulted useful for the extraction of both glucosinolates and phenolics in good amount and is environmentally acceptable as well as safe for food production.

Microalgae and cyanobacteria have attracted much attention for developing new biofuels production technologies. In particular, cyanobacteria seem to be promising in view of third generation bioethanol production. The most used source of inorganic carbon for algal cultivation is concentrated CO2 in air. However the use of this source can account of up to 50% of the biomass production costs. Bicarbonate salts, supplied to the culture medium, may be a valid alternative as source of inorganic carbon for photosynthetic microorganisms able to capture, use and recovery carbon from this substrate. In this study Synechocococcus PCC 7002 was used in order to test the capability of this strain to exploit bicarbonate and to elucidate the effect of such a carbon source on carbohydrates production. Batch experiments were carried out, using automatic control of pH and temperature (set to 8.5 and 28 °C, respectively). The concentrations of sodiumbicarbonate used were 5.5, 11, 22, 44 and 88 g L-1. The cyanobacteria was able to grow in all concentrationsof bicarbonate presenting high potential for production of biomass, with DCW 6 g L-1 in 44 and 88 g L-1 and productivity as high as 1.12 g L-1 day-1. An accumulation of carbohydrates was observed up to a maximum of 25% using 88 g L-1 of sodium bicarbonate, however this value was reached under nitrogen starvation in the stationary growth phase, when the carbon source was still limiting, because all the bicarbonate ion was completely consumed in all experiments.