The objective of this work is to provide a comprehensive study on algal biomass as feedstock for biogas production. Algae-derived biofuels are seen as one of the most promising solutions to mitigate ...climate change and as alternative to fast depleting of fossil fuels and oil reserves. Microalgae and macroalgae underwent an intense academic and industrial research, thanks to their capability to overcome the drawbacks related to the first and second generations of biomass resources. Major advantages of algae are: no competition with food crops for arable land, high growth rates, low fractions of lignin which reduces the need for energy-intensive pretreatment and compatibility with biorefinery approach implementation. However, some disadvantages such as the presence of high water content, seasonal chemical composition and the occurrence of inhibitory phenomena during anaerobic digestion, make algal biofuels not yet economically feasible although they are more environment friendly than fossil fuels.
•Biorefined seaweed residues demonstrated high potential for producing biogas.•Ambient extractions cascade improved the CH4 and biodegradation potentials.•Average CH4 yields on an annual basis were ...found between 107 and 405 mL gVS−1.•Seasonal composition and harvest site greatly affect digestion performance.
Very recently, integrated biorefinery approaches are being developed with the aim to produce high-value products for a variety of industries in conjunction with green energy from sustainable biomass. Macroalgae (seaweed) have been regarded as more sustainable compared to terrestrial crops, since they do not occupy land for growth. Macroalgal biomass changes greatly according to species and harvest season, which affects its chemical energy potential. This study was conducted seasonally on five species of brown seaweed over a yearlong period to investigate the effects of chemical composition variations, bioproducts extraction processes and inoculum acclimatation on methane production. As a result of the bioproducts extraction, it was found the seaweed residues exhibit a great potential to produce methane. Stoichiometric methane yield and C:N ratio changed in favour of an improved digestibility with bioconversion rates greater than 70% in some instances, i.e. achieved by Laminaria species and on the West coast Fucus serratus. The two Laminaria species investigated also presented the highest CH4 production rate, with Laminaria digitata reaching 523 mL CH4 gVS−1 and L. saccharina peaking at 535 mL CH4 gVS−1 with acclimatised and non-acclimatised sludge respectively.
Laminaria. sp. seaweeds have been recognised the potential to greatly contribute to the generation of renewable gaseous fuel via anaerobic digestion. Seaweed feedstock has been documented to ...consistently vary its biochemical composition with seasons, which affects stability of biomethane production. As currently seaweeds are too costly for use as third generation feedstock for biofuels, this paper investigates the biogas potential of the algal waste streams from the existing bio-industry. Analytical tests identified an improved digestibility of extracted residues (C:N > 20). Fermentation with and without inoculum acclimatation revealed the interaction between compositional seasonality and inoculum type to significantly affect methane production from the extracted samples. Summer’s composition has the most significant impact on methane production, with best results achieved with acclimatised inoculum (433 ml CH4 gVS−1 and final biodegradation of about 90%). Organics concentration (tCOD) and ash:volatile (A:V) ratio also play a major role in the bioconversion process. In particular, digestion with acclimatised inoculum better responds to A:V fluctuations across seasons, which produced the highest average methane yield of 334 ml gVS−1. Pretreatments are required to increase the biodegradation index in spring and summer when not using acclimatation.
•Biorefined L. hyperborea residues demonstrated improved digestibility (C:N > 20).•Seasonal composition and inoculum type to significantly affect methane production.•The ratio of ash to volatile solids in spring and winter of 0.21 is the lowest recorded.•Summer yielded the most with 433 ml CH4 gVS−1 with acclimatised inoculum.
This review focuses on stem cell-based therapies to treat skeletal muscle disorders, with a special emphasis on muscular dystrophies.
We briefly review previous attempts at cell therapy by the use of ...donor myoblasts, explaining the likely reasons for the poor clinical results; we then describe the use of the same cells in current promising trials for localized treatments of different diseases of skeletal muscle. Moreover, we discuss important novel findings on muscle stem/progenitor cell biology and their promise for future clinical translation. Preclinical and clinical applications of novel myogenic stem/progenitor cells are also described.
We summarize several ongoing clinical trials for different muscle disorders and the advances in the understanding of the biology of the myogenic progenitors used in such trials. On the basis of the currently available information, a prediction of developments in the field is proposed.
Cell walls and lignin component disruption treatments are needed to enhance the hydrolytic phase and the overall biodegradability of lignocellulosics during an anaerobic digestion process. Given ...their abundant availability in nature, low impact on food market prices and low lignin content, aquatic plants result in being particularly suitable for biofuel conversion.
A preliminary study on the effects of a Hollander beater mechanical pretreatment has been conducted in batch mode focusing on biogas yields from five different species of Irish seaweeds in co-digestion with sludge. A second experiment on Laminaria Digitata species has been carried out using a Response Surface Methodology (RSM) with treatment times (0–10 min), mesophilic range of temperatures (35–39 °C) and sludge amounts (100–300 ml). Results from biogas yields of treated macroalgae have been found to be up to 20% higher when compared to untreated ones. A mathematical model of the biogas volume behaviour has been developed and the ideal conditions identified.
► Relates different seaweed species to biogas yield and evaluates extra biogas yield from mechanical pretreatment. ► Compares co-digestion of treated/untreated macroalgae to sludge-only digestion. ► Mechanically pretreated feedstock produced up to 13% extra biogas. ► No significant effect by temperature variations in the mesophilic range 35–39 °C. ► Contains optimisation conditions for fermentation of Laminaria sp. to biogas.
Macroalgae have not met their full potential to date as biomass for the production of energy. One reason is the high cost associated with the pretreatment which breaks the biomass's crystalline ...structure and better exposes the fermentable sugars to anaerobes. In the attempt to overcome this technological barrier, the performance of a Hollander beater mechanical pretreatment is assessed in this paper. This pretreatment has been applied to a batch of Laminariaceae biomass and inoculated with sludge from a wastewater treatment plant. The derived biogas and methane yields were used as the responses of a complex system in order to identify the optimal system input variables by using the response surface methodology (RSM). The system's inputs considered are the mechanical pretreatment time (5–15 min range), the machine's chopping gap (76–836 μm) and the mesophilic to thermophilic range of temperatures (30–50 °C). The mechanical pretreatment was carried out with the purpose of enhancing the biodegradability of the macroalgal feedstock by increasing the specific surface area available during the anaerobic co-digestion. The pretreatment effects on the two considered responses are estimated, discussed and optimized using the tools provided by the statistical software Design-Expert v.8. The best biogas yield of treated macroalgae was found at 50 °C after 10 min of treatment, providing 52% extra biogas and 53% extra methane yield when compared to untreated samples at the same temperature conditions. The highest biogas rate achieved by treating the biomass was 685 cc gTS−1, which is 430 cc gTS−1 in terms of CH4 yield.
•Applies a novel mechanical pretreatment to Laminaria spp. biomass.•Response surface methodology (RSM) with a Box–Behnken Design (BBD) was applied.•Treatment time, reactor temperature and machine gap are the independent variables.•Mechanically treated biomass produced up to 52% extra biogas and 53% extra CH4.•Numerical and graphical optimizations were applied to reduce operating costs.
Miscanthus giganteous is probably the most fast growing and low nutrient bioenergy crop among lignocellulosic feedstocks. Despite its significant content in fermentable sugars, currently Miscanthus ...biomass is not used for biogas/methane production due to the high-lignin and low moisture content in the winter/spring harvest as well as cellulose crystallinity, which limit access to enzymatic action for all lignocellulosic feedstock. This study identified that a photocatalytic pretreatment prior to anaerobic digestion helps increase the substrate’s biodegradability by oxidising the lignin fraction, leading to increased methane yield up to 46% compared to the untreated. A novel photocatalyst was manufactured by reactive magnetron-sputtering deposition of TiO2 particles onto natural zeolite supports, which provided important trace elements for the anaerobic digestion process and retained a large surface area that acted as biofilm to boost growth of the microbial community. A load of 2% w/w catalyst in the bioreactor after 3 h of photocatalytic treatment led to 220 mLN gVS−1, with a net energy balance that is achieved for the whole process when treating the dispersed phase suspension at concentrations above 10 g m−3.
•Photolysed Miscanthus giganteous can yield up to 100 ml gVS−1 extra CH4.•TiO2 coated zeolites as photocatalysts help reduce NH3 in the reactor.•Natural zeolites provide microbial nutrients such as Na, Mg, Al, Si, K, Ca, and Fe.•A positive energy balance of UV treatment is found for substrate above 10.1 g m−3.
•A novel VGMS made up of recycled/natural and highly performing materials from the energy/environmental point of view, has been designed, prototyped and in lab/in field monitored through a ...multidisciplinary approach.•The technological issues, biometric parameters, and the acoustic, thermal and mechanical aspects were complimentarily investigated.•Thermal performance analyses showed interesting effect both during heating and cooling seasons.•An acoustic analysis demonstrated that the system acts well as a sound insulation system, and its high sound absorption could be exploited to reduce the urban canyoning effect.
Vegetation in architecture can be considered a proper design strategy that is aimed at improving not only the performances of buildings, but also the outdoor climate. Different technological solutions have been proposed over the years to cover buildings with vegetation, i.e. green roofs, green walls and green balconies. A particular typology of green wall, which has recently been gaining high consensus among designers, is the vertical greenery modular system (VGMS). The positive impact of this type of technology on the performance of buildings is related to several factors, such as the façade orientation, the use of the building, climatic conditions, the type of plants, the substrates and wall assemblies, as well as mechanical and technological issues. A multidisciplinary approach is therefore needed, and different skills have to be joined together right from the early design phase in order to optimize and balance all the aspects that are involved. In this framework, a research project has been carried out in Turin (North West Italy), with the aim of developing a novel VGMS, constituted by a modular box covered with vegetation, made up of recycled/natural and highly performing materials from the energy/environmental point of view. After the design phase, the actual performance of the VGMS was assessed, through laboratory and long-term in field monitoring, and at the same time, the technological issues, biometric parameters, and the acoustic, thermal and mechanical aspects were investigated.
Abstract
The architecture of a 64-channel ASIC for the readout of Silicon Photomultipliers in space experiments is described. Each channel embeds a front-end amplifier with a common gate topology ...followed by a 256 cells analogue memory with a sampling frequency of 200 MHz. A single memory cell includes a storage capacitor, a single-slope Analog-to-Digital Converter (ADC) with programmable resolution between 8 and 12 bits and the digital control logic. To save power, the A/D conversion is carried-out only when a trigger signal is received. The trigger can either be generated inside the ASIC or provided by an external source. The analogue samples are digitized in parallel, thus reducing the conversion dead time. The memory cells can be arranged in a single array or they can be grouped in shorter slots of 32 or 64 cells that work in a multi-buffer configuration. The channels can work independently or they can be synchronised to acquire the same time-frame in the full chip. The target power consumption is 5 mW/channel. The ASIC is being designed in a 65-nm CMOS technology. A digital-on-top flow is applied for the integration and final validation of the chip. The tape-out is scheduled in the first quarter of 2023.
Abstract
Cleft lip and palate (CL/P) is the most prevalent craniofacial birth defect in humans. None of the surgical procedures currently used for CL/P repair lead to definitive correction of hard ...palate bone interruption. Advances in tissue engineering and regenerative medicine aim to develop new strategies to restore palatal bone interruption by using tissue or organ-decellularized bioscaffolds seeded with host cells. Aim of this study was to set up a new natural scaffold deriving from a decellularized porcine mucoperiosteum, engineered by an innovative micro-perforation procedure based on Quantum Molecular Resonance (QMR) and then subjected to in vitro recellularization with human bone marrow-derived mesenchymal stem cells (hBM-MSCs). Our results demonstrated the efficiency of decellularization treatment gaining a natural, non-immunogenic scaffold with preserved collagen microenvironment that displays a favorable support to hMSC engraftment, spreading and differentiation. Ultrastructural analysis showed that the micro-perforation procedure preserved the collagen mesh, increasing the osteoinductive potential for mesenchymal precursor cells. In conclusion, we developed a novel tissue engineering protocol to obtain a non-immunogenic mucoperiosteal scaffold suitable for allogenic transplantation and CL/P repair. The innovative micro-perforation procedure improving hMSC osteogenic differentiation potentially impacts for enhanced palatal bone regeneration leading to future clinical applications in humans.
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