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Natural gas is a well known energy carrier. It is often used for producing heat and power, but can also be applied as a fuel in the transport sector. The production of synthetic natural gas (SNG) from coal or biomass is an interesting opportunity for both exploiting coal and biomass, and for replacing oil products for transportation and other uses. SNG has many important advantages with respect to other synfuels: it can be transported efficiently and cheaply using existing natural gas pipelines and distributing networks, it is an easily convertible feedstock, both in natural-gas combined-cycle power plants and in petrochemical facilities, it can count on a high social acceptance with respect to coal, and it can be stored underground, enabling efficient operation throughout the year independently of a fluctuating demand. Unfortunately, the commercial deployment of technologies for the production of SNG is currently constrained by technical barriers, so that more research is required before extensive applications on the industrial scale can be achieved. An important issue to be addressed is the strong exothermicity of the methane formation reactions, so that conventional fixed-bed catalytic reactors cannot be safely used (Sudiro et al., 2009). Following the 1970s energy crisis much work has been initiated in the US on coal-to-SNG: SNG process technologies and catalysts were developed and tested extensively. But most have been cancelled in the 1980 because of the changing energy picture. One industrial plant has actually been realized in North Dakota, which began operating in July 1984 and today produces more than 54 billion standard cubic feet of synthetic natural gas annually (1.53 billion Nm3/yr). Coal consumption is about 6 million tons each year. The heart of this plant is a building containing 14 gasifiers (www.dakotagas.com). Nowadays, the rise of natural gas prices have created a strong interest in producing SNG from the cheaper and much more abundant coal. A renewed interest in basing more energy consumption on coal and petcoke has resulted in a revival of several older technologies that have been enhanced to improve efficiency and to lower investment cost. Methanation is used as the final syngas purification step in the production of ammonia, but methanation for SNG production is more complex. The main industrial application of methanation has been the removal of CO from H2-rich feed gases in ammonia plants. With 5

Background Individuals with cerebral palsy (CP) report physical fatigue as a main cause of limitation, deterioration and eventually cessation of their walking ability. A consequence of higher level of fatigue in individuals with CP leads to a less efficient and long-distance walking ability. Research question This systematic review investigates the difference in 1) walking energy expenditure between individuals with CP and age-matched typically developing (TD) individuals; and 2) energetics of walking across Gross Motor Function Classification System (GMFCS) levels and age. Methods Five electronic databases (PubMed, Web of Science, CINAHL, ScienceDirect and Scopus) were searched using search terms related to CP and energetics of walking. Results Forty-one studies met inclusion criteria. Thirty-one studies compared energy expenditure between CP and age-matched controls. Twelve studies correlated energy expenditure and oxygen cost across GMFCS levels. Three studies investigated the walking efficiency across different ages or over a time period. A significant increase of energy expenditure and oxygen cost was found in individuals with CP compared to TD age-matched individuals, with a strong relationship across GMFCS levels. Significance Despite significant differences between individuals with CP compared to TD peers, variability in methods and testing protocols may play a confounding role. Analysis suggests oxygen cost being the preferred/unbiased physiological parameter to assess walking efficacy in CP. To date, there is a knowledge gap on age-related changes of walking efficiency across GMFCS levels and wider span of age ranges. Further systematic research looking at longitudinal age-related changes of energetics of walking in this population is warranted.

Modeling microalgal mixotrophy is challenging, as the regulation of algal metabolism is affected by many environmental factors. A reliable tool to simulate microalgal behavior in complex systems, such as wastewaters, may help in setting the proper values of operative variables, provided that model parameters have been properly evaluated. In this work, a new respirometric protocol is proposed to quickly obtain the half-saturation constant values for several nutrients. The protocol was first verified for autotrophic exploitation of ammonium and phosphorus (Monod kinetics), as well as of light intensity (Haldane model), further elaborated on specific light supply basis. It was then applied to measure the kinetic parameters of heterotrophic growth. The half-saturation constants for nitrogen and phosphorus resulted comparable with autotrophic ones. The dependence on acetate and dissolved oxygen concentration was assessed. Mixotrophy was modeled as the combination of autotrophic/heterotrophic reactions, implemented in AQUASIM, and validated on batch curves with/without bubbling, under nutrient limitation, and different light intensities. It was shown that the reliability of the proposed respirometric protocol is useful to measure kinetic parameters for nutrients, and therefore to perform bioprocess simulation.

Microalgal-bacteria consortia application on wastewater treatment has been widely studied, but a deeper comprehension of consortium interactions is still lacking. In particular, mixotrophic exploitation of organic compounds by microalgae affects gas (CO2 and O2) exchange between microalgae and bacteria, but it is not clear how environmental conditions may regulate algal metabolism. Using a respirometric-based protocol, we evaluated the combined effect of organic carbon and light intensity on oxygen production and consumption by C. protothecoides, and found that the chemical oxygen demand (COD) was not consumed when incident light increased. Batch experiments under different incident lights, with C. protothecoides alone and in consortium with activated sludge bacteria, confirmed the results obtained by respirometry. Continuous system experiments testing the combined effects of light intensity and residence time confirmed that, under limiting light, mixotrophy is preferred by C. protothecoides, and the nutrient (COD, N, P) removal capability of the consortium is enhanced.

Ensuring stability of the human vertical posture is a complex task requiring both anticipatory and compensatory postural strategies when a standing person performs fast actions and interacts with the environment, which can include other persons. How people adjust their preparatory and compensatory postural adjustments in situations when they interact with an active partner is still poorly understood. In this study we investigated the postural adjustments while two healthy persons played a traditional childhood game. While standing facing each other, they were asked to push with their hands against the hands of the opponent only, and to make the opponent to take a step. We explored strategies when pushing the opponent’s hands generated perturbations to the posture of both players and when one of the players withdrew the arms to neutralize the opponent’s pushing action. Electromyograms were recorded from the leg and trunk muscles and used to quantify early (EPAs), anticipatory (APAs) and compensatory (CPAs) postural adjustments, as well as the co-activation and reciprocal changes in the activity of agonist–antagonist pairs. Results showed higher indices of muscle co-activation during EPAs during the game compared to the control conditions. We found that postural preparation strategies defined whether a participant kept or lost balance during the game. Our results highlight the importance of muscle co-activation, the role of anticipation, and the difference in strategies while interacting with an active partner as compared to interactions with passive objects.

Protein-rich spent yeast is a waste by-product of brewing and other fermentation industry. A continuous-flow hydrothermal treatment called ‘flash hydrolysis’ was deployed for protein recovery and yeast disposal. A feed slurry with 1–15 wt% yeast was hydrolyzed at temperatures ranging between 160 and 280 °C for a very short residence time of 10 ± 2 s. Using 10 wt% yeast at 240 °C, 66.5% carbon, 70.4% nitrogen and 61.0% overall yeast biomass was solubilized in liquid hydrolysate. The liquid hydrolysate in which 63.1% of analyzed amino acids in yeast feed were solubilized, was tested as nutrient for cultivation of E. coli in a continuous bioreactor. The steady-state E. coli concentration was 1.18 g L−1 and 0.93 g L−1 using liquid hydrolysate and commercial yeast extract, respectively. Finally, the kinetic parameters for yeast solubilization (reaction order, activation energy and pre-exponential factor) were found to be 0.86, 21.3 kJ mol−1 and 19.36 [L g−1]n−1 s−1, respectively.

Metabolically engineered cyanobacteria are promising photosynthetic cell factories to produce valuable compounds in view of a bio-based industry. However, when the producer population is affected b...

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.

Cyanophycin, an intracellular reserve molecule synthetized by cyanobacteria, is considered as a potential biobased raw material for the industrial sector. It is usually produced through the cultivation of photosynthetic microorganisms in batch systems, which are affected by the high variability of cyanophycin accumulation due to varying growth phases, which lower the overall productivity. In this work, Synechocystis sp. PCC 6803 was cultivated in a continuous photobioreactor to increase cyanophycin productivity and to assess the feasibility of large-scale application. A stable production of the compound was obtained at steady-state. The effect of residence time and inlet phosphorus concentration on the biomass and cyanophycin productivity was evaluated, to identify the optimal conditions for its accumulation. A maximum value of cyanophycin productivity of about 30 mg L−1 d−1 was obtained, doubling the one achieved in the batch system. A quantitative correlation between the phosphorus quota and the cyanophycin produced was eventually proposed, highlighting a threshold of 4 mg of phosphorus per g of biomass for cyanophycin accumulation.

Patients with Parkinson&rsquo, 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&deg, and 120&deg, turn. As speculated, in single tasking, PD patients preferred to walk with a shorter stride length (p &lt, 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 &lt, 0.001), whereas the ground&ndash, foot contact will become greater (p &lt, 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&ndash, 7 g m&minus, 2 d&minus, 1 was obtained.

In conventional continuous bioreactor operations, it is a common practice to decouple the hydraulic retention time (HRT) from the solid retention time (SRT). When dealing with photosynthetic microorganisms, light intensity plays a major role in the growth kinetics; thus, the effect of HRT and SRT on biomass productivity may differ from that in chemotrophic bioreactors. In this study, we assessed the role of uncoupled SRT and HRT on biomass productivity in continuous photobioreactors (PBRs) based on simple mass balances, light transfer, and kinetic models to highlight the specific features of PBRs. Under a non-limiting nutrient supply, SRT is the fundamental variable used to maximize productivity and control the biomass concentration and light penetration in a PBR. Operating at SRT > HRT does not enhance the productivity. If the goal is biomass production, it is instead convenient to operate at SRT

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 supply of nutrients is a great issue to a sustainable scale-up of microalgal biofuels production, as these photosynthetic microorganisms require large amounts of N, P and other micronutrients to grow, which turns into high fertilizers demand. Additionally, recovery and reuse of nutrients (particularly N & P) are a must to reduce the non-point pollution emanating from their release into water or air during the downstream processing steps to biofuels or bioproducts. In the recent years, strong research efforts have been paid for developing nutrient recovery and recycling techniques, in order to reduce the net amount of fertilizers required. One possibility is exploiting nutrients from waste streams, such as wastewaters, while others focus on the recovery of N and P from the non-fuel fraction of the produced microalgal biomass, which is then recycled to the cultivation system, in a closed-loop perspective. In both cases, the presence of possible contaminants as well as nutrients bioavailability can impact the biomass productivity compared to standard synthetic media. Although the nutrients recovery and reuse has been in the forefront for a few years, there are no review publications available yet. In this paper, state-of-the art studies on nutrients recovery and recycling methods in microalgae processing from the last decade are reviewed. The study focuses on the different N and P recovery methods and yields, as well as on their subsequent use in algal cultivation and impact on algae productivity. Possible bioproducts exploitation is considered, and perspectives of closed-loop material balances on a large-scale are eventually provided.

Nonlinear Bayesian filtering of surface electromyography (EMG) can provide a stable output signal with little delay and the ability to change rapidly, making it a potential control input for prosthetic or communication devices. We hypothesized that myocontrol follows Fitts’ Law, and that Bayesian filtered EMG would improve movement times and success rates when compared with linearly filtered EMG. We tested the two filters using a Fitts’ Law speed-accuracy paradigm in a one-muscle myocontrol task with EMG captured from the dominant first dorsal interosseous muscle. Cursor position in one dimension was proportional to EMG. Six indices of difficulty were tested, varying the target size and distance. We examined two performance measures: movement time (MT) and success rate. The filter had a significant effect on both MT and success. MT followed Fitts’ Law and the speed-accuracy relationship exhibited a significantly higher channel capacity when using the Bayesian filter. Subjects seemed to be less cautious using the Bayesian filter due to its lower error rate and smoother control. These findings suggest that Bayesian filtering may be a useful component for myoelectrically controlled prosthetics or communication devices. NEW & NOTEWORTHY Whereas previous work has focused on assessing the Bayesian algorithm as a signal processing algorithm for EMG, this study assesses the use of the Bayesian algorithm for online EMG control. In other words, the subjects see the output of the filter and can adapt their own behavior to use the filter optimally as a tool. This study compares how subjects adapt EMG behavior using the Bayesian algorithm vs. a linear algorithm.

Nannochloropsis is commonly recognized as a valuable biomass source for the production of both biofuels and high value nutraceuticals compounds. Phosphorus is one of the main nutrients affecting microalgal growth and composition. In this work, the effect of using higher P concentrations in cultivation of Nannochloropsis salina was studied showing an increase of the phosphate uptake rate related with the higher P availability in the medium. This enhanced uptake was preferentially stored in the cells rather than being used for growth, indicating the activation of a luxury uptake phenomenon. The intracellular P storage in N. salina was measured and the presence of polyphosphate granules was detected. The kinetic of accumulation and consumption of internal phosphorus was quantified in batch cultures, as a function of P concentration and light intensity. Finally, the effect of P, also in combination with different light supply rates was analyzed in continuous steady-state experiments, showing that operating in this mode strongly influences not only the biomass productivity, but also the nutrient uptake.

In this paper, the acidic pretreatment of microalgal biomass is investigated, and the solubilized biomass and hydrolyzed sugars were evaluated. The process is analyzed through the severity factor approach (acidic combined severity factor (ACSF)). A suitable kinetic model is developed and applied, and it is shown that the severity factor theory works. A discussion and comparison are presented with respect to the literature methods, which are mainly related to lignocellulosic biomass. In the case of microalgae, reaction orders for biomass and acid are shown to be the main parameters, and no other assumptions are needed. Two regions of the acidic treatment process have to be evaluated: low and high reactivity regions. Furthermore, a suitable experimental design is required in order to provide an appropriate reaction spectrum to obtain a good estimation of the kinetic parameters. A logarithmic severity factor range (ln ACSF) between 5 and 6 is able to solubilize around 80% of biomass and to hydrolyze more than 90% of sugars present in the biomass.

This study investigated the behaviour of dynamic membrane (DM) filtration for the treatment of stabilised landfill leachate in a bench-scale pre-anoxic and aerobic submerged dynamic membrane bioreactor (DMBR). Four meshes with different openings (10, 52, 85 and 200 μm) were tested to support the development of DM. Differences were observed among the meshes in supporting the development of the cake layer constituting the DM. The treatment of landfill leachate had an impact on sludge characteristics resulting in deteriorated filtration performance of the DM. Effluent turbidity was often higher than 100 NTU for larger mesh pore size (85 and 200 μm). Low effluent turbidity was achieved with meshes with 10 and 52 μm (13 ± 2 and 26 ± 4 NTU, respectively) although at membrane fluxes lower than 10 L m− 2 h−1. The bioreactor exhibited a moderate organics removal of 50–60% and an ammonia oxidation between 80 and 90%. Incomplete nitrification was observed due to increased concentrations of free ammonia and free nitrous acid, with nitrite effluent concentrations up to 1062 mgNO2 --N L−1. Due to the large presence of refractory organic matter in landfill leachate, denitrification was limited resulting in a total nitrogen removal of approximately 20%. © 2018 Elsevier Ltd

Research pertaining to yoga and children with cerebral palsy (CP) is negligible. The primary purpose of this study was to determine the domains of the International Classification of Functioning, Disability, and Health (ICF) model and levels of evidence for yoga and adults with stroke and multiple sclerosis (MS), and children. A secondary purpose was to decide whether any inferences could be made for children with CP.This study included a meta-analysis.A systematic review was performed of yoga and said populations. Outcome measures were categorized according to the ICF model domains of body structures and function, activity, and quality of life. Effect sizes (ESs) were calculated by using Cohen's d. Since there were few commonalities among outcome measures and reporting of outcomes within and among diagnostic groups, direct comparisons of ESs were difficult. Hence, we chose to evaluate the impact of yoga as compared with the control group or other physical exercise by using a General Linear Mixed Model.There were 5 yoga studies with stroke, 15 with MS, and 12 with children. Studies with children used outcomes related to body structure and function, whereas those with stroke and MS used outcomes across all three domains of the ICF. ESs varied from negligible to medium for stroke, from negligible to large for MS and children.The findings of this meta-analysis indicate that yoga is no better or worse than other exercise modalities as a treatment intervention for adults with stroke and MS, and children. Group yoga classes are typically social environments that can contribute to increased physical progress and feelings that contribute to quality of life, which may benefit individuals with CP. More research on yoga and particularly in children and adults with CP would yield valuable information for creating effective and safe yoga programs with a rich array of benefits.

In this study, acidic and enzymatic hydrolysis were carried out with Chlorella vulgaris and Scenedesmus obliquus, and a systematic evaluation of the yeast inoculum optimization (Saccharomyces cerevisiae and Pichia stipitis) during the hydrolysates fermentation was made. Acidic hydrolysis with 3% of sulphuric acid at 121 °C and 30 min of reaction time (50–100 g/L of biomass) was found as best condition, and more than 90% of sugars recovery in the liquid phase was achieved even though S. obliquus be more sensible to thermal degradation than C. vulgaris. On the other hand, during the enzymatic hydrolysis, ultrasonication showed to be an effective method of biomass pretreatment to provide higher enzyme accessibility what together with a combination between amylases, cellulase/hemicellulase mix and pectinases achieved more than 90% of sugars recovery in 8 h of hydrolysis time. Thus, both treatments could recover efficiently the sugars present in microalgae. After inoculum optimization (concentration and consortium between S. cerevisiae and P. stipitis) and saline influence on yeast performance were evaluated, the fermentation of microalgal hydrolysate exhibited very different profiles in comparison with the control conditions and ethanol biochemical yield changed between 45% and 61%, emphasizing the importance to optimize this last but not less important step of ethanol production.

Nutrient recycling is of paramount importance for microalgal cultivation aimed at biofuels production. Though different techniques have been assessed at lab-scale level, less information is available on the actual nutrient recovery yields and on the energy balance of a large-scale closed-loop process. In this work two technologies, namely anaerobic digestion (AD) and flash hydrolysis (FH), were investigated by process simulation analysis and compared in terms of both nutrients recovery and energy profitability (EROEI index). FH performs better in terms of nutrients recycling, with up to 70% and 60% of phosphorus and nitrogen recovered in bio-available forms, while incomplete biodegradability limits the nutrients recovery extent in AD. On the other hand, AD requires much lower energy inputs, achieving EROEI values always favorable (2.3–5), while the high thermal requirements of FH, even with heat integration, highlight the need of improving the operating conditions to reduce the energetic burden of this technology (EROEI = 0.8–2.4).