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The theoretical basis for the cyclical generation of macroscopic reconnected magnetic fields in low collisionality plasma regimes is formulated. The relevant process is sustained by the “thermal” energy of the electron population.In particular, an oscillatory mode propagating along and across a confining magnetic field is identified that involves the magnetic reconnection region where the ratio of the longitudinal to transverse electron thermal conductivity is relatively large. A periodic exchange of reconnected magnetic field conductivity energy with electron thermal energy is sustained within a region that remains significant even when the magnetic field configuration from which the mode can emerge involves large- scale distances. The mode growth rate depends on the particle density gradient (aligned with the electron temperature gradient) and the relevant particle diffusion coefficient. A different magnetic reconnection process driven by the plasma pressure gradient was identified explaining the origin of the observed sawtooth oscillations of magnetically confined plasmas.

In order to extend observations on the spontaneous electron density peaking in Neon doped plasmas already reported in FTU [1], some sessions have been performed by injecting Helium gas on the L-mode plasmas during the last two experimental campaigns. This favorable scenario, which can fall within so called "highly radiative" or "plasma detachment" themes, is investigated in this paper. It has been recorded that, not only the total amount of puffed Helium, but also the rate of injection can intervene in triggering a particle inflow. VUV spectroscopy measurements can help to evaluate the fraction of electrons that can be attributed to the ones stripped by Helium ionization in the electron density rise, at this purpose a model to estimate concentrations of impurities is proposed. The description of the Helium effect on plasma behavior, especially with respect to the density peaking and edge conditioning, by varying plasma parameters and shape, is exposed.

As littoral and riparian environments are in decline and survival of many aquatic plants is threatened by anthropic activities all over the globe, the conservation of macrophyte diversity should be considered a priority, because of their key role in freshwater ecosystems. High-throughput techniques, such as remote sensing spectroscopy, genetics and phylogenetics, have been explored in the last decade to support and enhance operational diversity monitoring. These techniques have opened new ways of measuring biodiversity, especially in forest and grassland systems, but a sound link between spectral and phylogenetic features with plant functional characteristics has yet to be established. The idea behind macroDIVERSITY, a new national project, funded by the Italian Ministry of Education, University and Research (2020-2023), is that phylogenetic and spectral diversity measures can be integrated into a multidimensional data-driven framework for mapping plant traits and functions across scales and gradients. To this objective, we will collect data on macrophyte traits, diversity, and spectral reflectance from plots sampled over selected lakes and wetlands in Italy, according to robust experimental design. A fully resolved supertree, obtained from DNA markers analysis integrating available data and new sequencing, will be used for assessing the evolutionary diversity of the species assemblage, highlighting the phylogenetic signal in the context of the community traits information. Hyperspectral imaging data acquired from proximal platforms and airborne drones at centimetre scale will be used for modelling bio-chemical and functional macrophyte traits (e.g. canopy morphology, productivity, pigments and nutrients content). Environmental parameters collected and diversity metrics derived will be eventually merged into a machine-learning framework for mapping macrophyte functional diversity (richness and divergence). The project outcomes are expected to impact on applied ecology studies focusing on delineating plant diversity using remote sensing data, and investigating the role played by species interactions and community complexity in regulating aquatic ecosystem quality.

Over the past decades, several studies elucidated the effect of the loss of aquatic plant diversity in freshwater ecosystems. Several strategies and approaches for macrophytes diversity conservation have considered taxonomical or functional features, and only in the last years the evolutive dimension of plant communities was also considered [1]. Phylogenetic diversity (PD) dimension, reflecting the accumulation of genetic, phenotypic and phenological differences between evolutionary lineages, may have an important role in the biodiversity conservation. It reflects. Consequently, preserving sites with the greatest amount of phylogenetic variability will, in turn, preserve the greatest variation.in organismal features and, in some cases, functions [2]. Developing from 2020 and 2023, macroDIVERSITY project (PRIN 2017) aims at integrate spectral (SD) and phylogenetic (PD) diversity to map the functional diversity of freshwater macrophyte communities at different spatial scales and trophic gradients. Within the framework of macroDIVERSITY, , we will collect data on macrophyte diversity from plots sampled over selected lakes in Central and Northern Ital, based on robust experimental design. The PD of each plot will be quantified using the Faith's metric. The Net Relatedness index (NRI) and the Nearest Taxon Index (NTI) will also be used to quantify the degree of the community phylogenetic clustering/overdispersion among species within each plot [3]. Using the described approach, we aim to 1) delineate the evolutionary relationships within the wetland communities; 2) obtain PD metrics of each macrophyte community/ecosystem; 3) achieve a feedback on wetlands genetic sustainability of Central and Northern Italy.

The introduction of a proper divertor in meaningful fusion burn experiments is at times advocated with the argument that it addresses the rcactor relevant issue of ash and impurity control and it allows easier access to the H-mode regime. On the other hand, a divettor decreases the volume available for the plasnna and introduces structutes that have to withstand high thermal wall loadings and the effects of disruptions in a high magnetic field environment. Other related questions are whether the density profiles that characterize the H-regime, for which a divertor is introduced, are optimal for ignition, whether the divertor has indeed led to cleaner core plasmas than those produced in limiter devices , and whether other means to remove the alfa-particles produced by fusion reactions, e.g. during their slowing down, are more appropriate even in principle. In the Ignitor operating scenario of reference, ignition can be reached by ohmic heating only. The edge conditions are characterized by relatively low temperatures and high densities. In high density regimes , an extensive series of experiments has observed a low level of impurity in the plasma core, thanks to both reduced sputtering from the wall and improved screening properties of the adjacent plasma. Radiation losses gain importance in dissipating the power leaving the main plasma and the whole scrape off layer contributes in dispersing the energy of the particles impinging on the material walls, even without the introduction of additional impurities. Therefore, the extended limiter solution, with the plasma wetting a large fraction of the first wall surface, has been preferred over that of a traditional divertor configuration.