A CRITICAL ENVIRONMENTAL ANALYSIS OF STRATEGIC MATERIALS TOWARDS ENERGY TRANSITION

Global consumption of materials is rising rapidly leading to an increase in environmental impacts associated with the supply chain. Similar issues also affect a set of materials strategic for the transition towards a sustainable energy production and distribution system: i.e. materials employed in renewable energy (wind turbines and photovoltaic panels), energy storage, electrolysers, electricity distribution networks and electric vehicle charging infrastructure. The analysis identifies, maps and de-fines a priority hierarchy for the environmental risks generated along the life-cycle of strategic raw materials. Standard construction material such as iron, steel and concrete showed the lowest environmental risks whereas platinum and iridium presented by far the highest impacts (respectively about 24.100 and 14.700 kg CO2 eq, 354.000 and 216.000 MJ, and 140 and 83 m3 of water for 1 kg of raw material). Recycled materials have shown to enable the lowering of the environmental risk associated with some raw material production processes (i.e. copper, lead, aluminium, nickel, manganese), whereas specific materials (i.e. platinum, iridium, indium, dysprosium) and related applications will need to be monitored to guarantee a sustainable transition towards renewable energies

Life Cycle Assessment of a Circular Economy Process for Tray Production via Water-Based Upcycling of Vegetable Waste

With one-third of food being wasted at the various steps of the value chain, there is a large amount of biomass constantly being discarded, also wasting the resources consumed for its production. Several strategies have been proposed to use this biomass as a source of raw materials for the production of plastic alternatives, but the environmental impact parameters have rarely been estimated to understand if the proposed process provides an overall benefit. The purpose of this paper is to analyze, through an experimental laboratory campaign, the production process of a vegetable biocomposite material obtained by valorization of biomass from two sources: unsold vegetables from a wholesale market and carrot pomace obtained as a byproduct of juicing. The obtained biocomposite films were thermoformed into trays to replace the traditional plastic food containers made principally with PET. Different scenarios for the lab-scale production of trays were evaluated by testing two water-based processing methods for the two types of biomass used. In order to understand which of the four scenarios was the least impactful, the global warming potential, the cumulative energy demand, and the water scarcity index were used as indicators. Among the different lab-scale processing scenarios for the upscaling of vegetable waste, the least impactful was starting from the unsold/discarded vegetables collected at the wholesale market that were processed via water-based hydrolysis catalyzed by formic acid. Impact parameters were comparable or better than two traditional polymers (PET and HDPE) and two biopolymers (PLA and biopolymer from starch), showing that this process has excellent potential, from an environmental point of view, of substituting plastic packaging

Life cycle assessment of hydrogen-powered city buses in the High V.LO-City project: integrating vehicle operation and refuelling infrastructure

During the project High V.LO-City, which ended in December 2019, 14 hydrogen fuel cell buses were operated in four European cities. This paper aims at presenting total emissions through the lifetime of fuel cell buses with different hydrogen production options, including the refuelling stations. The environmental assessment of such bus system is carried out using the life cycle assessment methodology. Three hydrogen production pathways are investigated: water electrolysis, chlor-alkali electrolysis and steam methane reforming. Fuel economy during bus operation is around 10.25 KgH2/100 km, and the refuelling station energy demand ranges between 7 and 9 KWh/KgH2. To support the inventory stage, dedicated software tools were developed for collecting and processing a huge amount of bus data and refuelling station performance, for automating data entry and for impacts calculation. The results show that hydrogen-powered buses, compared to a diesel bus, have the potential to reduce emissions during the use phase, if renewables resources are used. On the other hand, impacts from the vehicle production, including battery pack and fuel cell stack, still dominate environmental load. Consequently, improving the emission profile of fuel cell bus system requires to promote clean electricity sources to supply a low-carbon hydrogen and to sharpen policy focus regarding life cycle management and to counter potential setbacks, in particular those related to problem shifting and to grid improvement. For hazardous emissions and resource use, the high energy intensity of mining and refining activities still poses challenges on how to further enhance the environmental advantages of fuel cells and battery packs

Age-Dependent Neuropsychiatric Symptoms in the NF-κB/c-Rel Knockout Mouse Model of Parkinson’s Disease

Non-motor symptoms are frequently observed in Parkinson’s disease (PD) and precede the onset of motor deficits by years. Among them, neuropsychiatric symptoms, including anxiety, depression, and apathy, are increasingly considered as a major challenge for patients with PD and their caregivers. We recently reported that mice lacking the nuclear factor-κB (NF-κB)/c-Rel protein (c-rel–/– mice) develop an age-dependent PD-like pathology and phenotype characterized by the onset of non-motor symptoms, including constipation and hyposmia, starting at 2 months of age, and motor deficits at 18 months. To assess whether c-rel–/– mice also suffer from neuropsychiatric symptoms, in this study we tested different cohorts of wild-type (wt) and c-rel–/– mice at 3, 6, 12, and 18–20 months with different behavioral tests. Mice lacking c-Rel displayed anxiety and depressive-like behavior starting in the premotor phase at 12 months, as indicated by the analysis with the open field (OF) test and the forced swim test with water wheel (FST), respectively. A deficit in the goal-oriented nesting building test was detected at 18–20 months, suggesting apathetic behavior. Taken together, these results indicate that c-rel–/– mice recapitulate the onset and the progression of PD-related neuropsychiatric symptoms. Therefore, this animal model may represent a valuable tool to study the prodromal stage of PD and for testing new therapeutic strategies to alleviate neuropsychiatric symptoms

Unravelling the DNA sequences carried by Streptomyces coelicolor membrane vesicles

Membrane vesicles (MVs) are spherical particles with nanoscale dimensions and characterized by the presence of diverse cargos, such as nucleic acids, proteins, lipids, and cellular metabolites. Many examples of (micro)organisms producing MVs are reported in literature. Among them, bacterial MVs are of particular interest because they are now considered as the fourth mechanism of horizontal gene transfer. Streptomyces bacteria are well-known for their ecological roles and ability to synthesize bioactive compounds, with Streptomyces coelicolor being the model organism. It was previously demonstrated that it can produce distinct populations of MVs characterized by different protein and metabolite cargos. In this work we demonstrated for the first time that MVs of S. coelicolor carry both DNA and RNA and that their DNA content represents the entire chromosome of the bacterium. These findings suggest that MV DNA could have a role in the evolution of Streptomyces genomes and that MVs could be exploited in new strain engineering strategies

Environmental assessment of vegetable crops towards the water-energy-food nexus: A combination of precision agriculture and life cycle assessment

The increase in world population and the resulting demand for food, water and energy are exerting increasing pressure on soil, water resources and ecosystems. Identification of tools to minimise the related environmental impacts within the food–energy–water nexus is, therefore, crucial. The purpose of the study is to carry out an analysis of the agri-food sector in order to improve the energy-environmental performance of four vegetable crops (beans, peas, sweet corn, tomato) through a combination of precision agriculture (PA) and life cycle assessment (LCA). Thus, PA strategies were identified and a full LCA was performed on actual and future scenarios for all crops in order to evaluate the benefits of a potential combination of these two tools. In the case study analysed, a life cycle approach was able to target water consumption as a key parameter for the reduced water availability of future climate scenarios and to set a multi-objective function combining also such environmental aspects to the original goal of yield maximisation. As a result, the combination of PA with the LCA perspective potentially allowed the path for an optimal trade-off of all the parameters involved and an overall reduction of the expected environmental impacts in future climate scenarios

Broad-band X-ray spectral evolution of GX 339-4 during a state transition

We report on X-ray and soft gamma-ray observations of the black-hole candidate GX 339-4 during its 2007 outburst, performed with the RXTE and INTEGRAL satellites. The hardness-intensity diagram of all RXTE/PCA data combined shows a q-shaped track similar to that observed in previous outbursts.The evolution in the diagram suggested that a transition from hard-intermediate state to soft-intermediate state occurred, simultaneously with INTEGRAL observations performed in March. The transition is confirmed by the timing analysis presented in this work, which reveals that a weak type-A quasi-periodic oscillation (QPO) replaces a strong type-C QPO. At the same time, spectral analysis shows that the flux of the high-energy component shows a significant decrease in its flux. However, we observe a delay (roughly one day) between variations of the spectral parameters of the high-energy component and changes in the flux and timing properties. The changes in the high-energy component can be explained either in terms the high-energy cut-off or in terms of a variations in the reflection component. We compare our results with those from a similar transition during the 2004 outburst of GX 339-4.Comment: 8 pages, 6 figures, accepted for publication in MNRAS Main Journa

Fast modularisation and aomic decomposition of ontologies using axiom dependency hypergraphs

In this paper we define the notion of an axiom dependency hypergraph, which explicitly represents how axioms are included into a module by the algorithm for computing locality-based modules. A locality-based module of an ontology corresponds to a set of connected nodes in the hypergraph, and atoms of an ontology to strongly connected components. Collapsing the strongly connected components into single nodes yields a condensed hypergraph that comprises a representation of the atomic decomposition of the ontology. To speed up the condensation of the hypergraph, we first reduce its size by collapsing the strongly connected components of its graph fragment employing a linear time graph algorithm. This approach helps to significantly reduce the time needed for computing the atomic decomposition of an ontology. We provide an experimental evaluation for computing the atomic decomposition of large biomedical ontologies. We also demonstrate a significant improvement in the time needed to extract locality-based modules from an axiom dependency hypergraph and its condensed version

Network-based analysis reveals differences in plant assembly between the native and the invaded ranges

Associated with the introduction of alien species in a new area, interactions with other native species within the recipient community occur, reshaping the original community and resulting in a unique assemblage. Yet, the differences in community assemblage between native and invaded ranges remain unclear. Mediterranean grasslands provide an excellent scenario to study community assembly following transcontinental naturalisation of plant species. Here, we compared the community resemblance of plant communities in Mediterranean grasslands from both the native (Spain) and invaded (Chile) ranges. We used a novel approach, based on network analysis applied to co-occurrence analysis in plant communities, allowing us to study the co-existence of native and alien species in central Chile. This useful methodology is presented as a step forward in invasion ecology studies and conservation strategies. We found that community structure differed between the native and the invaded range, with alien species displaying a higher number of connections and, therefore, acting as keystones to sustain the structure within the invaded community. Alien species acting like keystones within the Chilean grassland communities might exacerbate the threat posed by biological invasions for the native biodiversity assets. Controlling the spread of the alien species identified here as keystones should help managing potential invasion in surrounding areas. Network analyses is a free, easy-to-implement and straightforward visual tool that can be widely used to reveal shifts in native communities and elucidate the role of multiple invaders into communitie