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The EU H2020 GECO project is primarily aimed to set-up technologies to lower emissions from geothermal power generation by capturing them for either reuse or storage, to turn captured emissions in to commercial products and demonstrate the technical and economic feasibility of the injection method. To achieve this goal a site specific characterization and modelling of geology and geochemistry of the geothermal reservoir are in progress for optimization of the injection experiments at four distinct geothermal systems throughout Europe are in progress. The Italian GECO demonstration site is Castelnuovo, which is located in the northeaster side of the Larderello geothermal area and where Graziella Green Power and Storengy are planning to exploit a deep seated high temperature resource for power production with the scope of no non condensable gases (NCGs), release in atmosphere. The geothermal fluid will be extracted from 2 production wells and then it will be reinjected in the reservoir by mean of 1 reinjection well. A Zero emissions ORC power plant will produce 5MWe. For the geological assessment of Castelnuovo site an integrated methodology was designed and is applied to obtain the most reliable and accurate assessment of the site. The geological, reservoir and chemical reactive modelling are performed using field or labs data and observations (i.e., geology, geophysics, geochemistry surveys). Moreover, we adopted a double scale approach where regional, and larger, model was built to provide constrains to local, smaller and detailed, models. At regional scale a geological model including the main structures of the area is modelled to create the geometries needed to local models. At locale scale, firstly the thermal steady state of the rock volume and secondly the reinjection simulations on reservoir and fluids-rocks interaction during the reinjection are numerically computed.

GECO (Geothermal Emission Control) is an international research project that started in 2018, funded by the EU through the H2020. The project consortium is led by Carbfix and consists of 18 partners from 9 countries across Europe. The GECO project builds upon the success of the recently developed Carbfix gas re-injection method. Applying the Carbfix method advanced considerably our ability to clean the exhaust gases emitted by geothermal power plants based on a novel water dissolution method in a dedicated scrubbing tower. The injection of the resulting gas charged waters into the subsurface disposes the captured gases within precipitated minerals that remain stable over geologic time. This method has been demonstrated to be successful and has been running at the Hellisheidi power plant in Iceland for the past six years. Through this industrial scale demonstration, this new method has been demonstrated 1) to offer considerable cost savings compared to other approaches to capture and dispose acidic carbon and sulphur bearing gases; 2) to be far more environmentally compared to other available technologies; and 3) to aid in the long-term viability of geothermal systems by enhancing the permeability of fluid injection wells. The goal of the GECO project is to adopt the Carbfix reinjection technology, together with emission gas reuse schemes, to become a standard to the geothermal power industry worldwide through the application of gas injection to five new sites across Europe. By consistently monitoring the reactions that occur in the GECO field sites, each having a distinct geology, we will be able to generalise these findings to create a tool for predicting the chemical behaviour of a large number of other systems before they are developed for geothermal energy. Such tools have the potential to decrease both the risk and the cost of future geothermal energy projects. The GECO project aims to provide a new general, efficient, cost-effective, and environmentally benign technology to clean and permanently store or reuse geothermal exhaust gases throughout Europe and the rest of the world.

Mobile integrons are widespread and clinically relevant drivers of antibiotic resistance. Acting as genetic platforms, they allow bacteria to capture, express and re-order mobile antibiotic resistance gene cassettes, whose expression levels depend on their distance from the promoter, located at the integration site. Cassettes can be integrated and excised by the integrase enzyme, produced by the bacteria in time of stress. It has been hypothesized that integrons allow bacteria to adapt quickly to changing antibiotic pressures by reshuffling the cassette order, and therefore their resistance levels, such that integrons provide ‘adaptation on demand’. To test this ‘adaptation on demand’ hypothesis, I used a custom three-cassette integron system transformed in both E. coli and P. aeruginosa. I first investigated the effect of cassette position on cassette expression at the phenotypic, transcriptional and translational level and confirmed a transcriptional origin of the cassette expression gradient, which was either strengthened or reduced by additional translational effects. I then combined experimental evolution and whole genome sequencing to quantify the evolvability benefits of cassette shuffling against increasing concentrations of antibiotics. By comparing strains with and without a functional integrase and focusing on two different cassettes and antibiotics, I observed striking differences in population survival rates and evolutionary pathways depending on the cassette and on the antibiotic. On one hand, with the antibiotic gentamicin and the aadB cassette, I saw an increase in evolvability and identified extensive cassettes rearrangements as well as cassette duplications in the populations with a functional integrase. On the other hand, with piperacillin and blaVEB-1, integrase activity was linked with decreased evolvability and a much lower rearrangement frequency, but I observed unexpected integron-mediated recombinations in the plasmid conjugation machinery. These results highlight the key impact of antibiotics and cassette characteristics on the potential integrase shuffling benefits and provide novel insights on the dynamics controlling cassettes and integrase prevalence in the environment. In my experiments, high cassette mobility was necessary to compensate for the high fitness cost of integrase expression, or the integrase was a burden for bacteria survival. Moreover, I showed integrase activity was not limited to cassette shuffling or cassette acquisition but may also promote cassette duplication and beneficial off-target recombination, with far-reaching consequences on plasmid and antibiotic resistance evolution.

Human diseases of zoonotic origin are a major public health problem. Simian foamy viruses (SFVs) are complex retroviruses which are currently spilling over to humans. Replication-competent SFVs persist over the lifetime of their human hosts, without spreading to secondary hosts, suggesting the presence of efficient immune control. Accordingly, we aimed to perform an in-depth characterization of neutralizing antibodies raised by humans infected with a zoonotic SFV. We quantified the neutralizing capacity of plasma samples from 58 SFV-infected hunters against primary zoonotic gorilla and chimpanzee SFV strains, and laboratory-adapted chimpanzee SFV. The genotype of the strain infecting each hunter was identified by direct sequencing of the env gene amplified from the buffy coat with genotype-specific primers. Foamy virus vector particles (FVV) enveloped by wild-type and chimeric gorilla SFV were used to map the envelope region targeted by antibodies. Here, we showed high titers of neutralizing antibodies in the plasma of most SFV-infected individuals. Neutralizing antibodies target the dimorphic portion of the envelope protein surface domain. Epitopes recognized by neutralizing antibodies have been conserved during the cospeciation of SFV with their nonhuman primate host. Greater neutralization breadth in plasma samples of SFV-infected humans was statistically associated with smaller SFV-related hematological changes. The neutralization patterns provide evidence for persistent expression of viral proteins and a high prevalence of coinfection. In conclusion, neutralizing antibodies raised against zoonotic SFV target immunodominant and conserved epitopes located in the receptor binding domain. These properties support their potential role in restricting the spread of SFV in the human population., Author summary Foamy viruses are the oldest known retroviruses and have been mostly described to be nonpathogenic in their natural animal hosts. Simian foamy viruses (SFVs) can be transmitted to humans, in whom they establish persistent infection, as have the simian lenti- and deltaviruses that led to the emergence of two major human pathogens, human immunodeficiency virus type 1 (HIV-1) and human T lymphotropic virus type 1 (HTLV-1). Such cross-species transmission of SFV is ongoing in many parts of the world where humans have contact with nonhuman primates. We present the first comprehensive study of neutralizing antibodies in SFV-infected humans. We showed high titers of neutralizing antibodies in the plasma of most SFV-infected individuals. Neutralizing antibodies target the dimorphic portion of the envelope protein surface domain that overlap with the receptor binding domain. SFV-specific antibodies target epitopes conserved over 8 million years of co-speciation with their nonhuman primate host. Greater neutralization potency in infected individuals was statistically associated with smaller SFV-related hematological changes. In conclusion, our results suggest the protective action of neutralizing antibodies against SFV infection and spread in the human population.