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Plastic hotspot areas in riverine habitats: Riparian vegetation diversity and structure entrap riverine plastics
No full textPlastics are a significant environmental problem, accumulating in ecosystems and causing harmful effects. While
macroplastics in rivers have only recently gained attention, most studies focus on their transport to the sea,
neglecting the fact that plastics often remain within fluvial systems. Previous research has primarily considered
abiotic factors in this transport process. However, recent findings indicate that vegetation plays a crucial role in
trapping plastics in urban and lowland watercourses. The role and structure of riparian vegetation in plastic
entrapment are poorly understood. This study investigates the relationship between vegetation structure and
plastic entrapment applying the 3D Vegetation Index (3DVI) to quantify vegetation complexity and its capacity to
trap plastics. Field data on plastics and vegetation were collected from six rivers in central Italy across three
riverine zones. Results show a significant correlation between macroplastics trapped in vegetation and vegetation
structure, with denser and more diverse plant communities trapping more plastics. Particularly, a significant
regression between 3DVI and plastics in vegetation was observed only in the lower river zone. The higher the
3DVI value, the more complex the vegetation, indicating greater plastic trapping efficiency. These findings
suggest that biotic factors, particularly vegetation structure, are important variables for driving riverine plastic
entrapment at local scales. This study is the first to apply a vegetation index to describe the complexity and
diversity of plant communities related to plastic entrapment. Future research urgently needs to unveil this
phenomenon at a global scale as well as to focus on the interactions and effects of macroplastics on plants. Understanding
plant structures and 3DVI usage in retaining plastics can help identify plastic hotspot areas and
inform mitigation and clean-up efforts to address plastic pollution effectivel
Evolution of Griffiths-like Anomaly in Isostructural Swedenborgite Compounds Ho1−xErxBaCo4O7+δ
No full textIn this study, we investigate the presence of the Griffiths-like anomaly in the geometrically frustrated antiferromagnet (Formula presented.) (Formula presented.) and globally its absence in (Formula presented.) (Formula presented.), despite only small differences in the ionic radii, f-electron occupancy, and the corresponding crystal structures of the (Formula presented.) and (Formula presented.) -members. Previous studies have identified the Griffiths phase in the Dy-analog, (Formula presented.) (Formula presented.), suggesting certain inherent features of this class of materials that regularly give rise to such anomalies. To explore the curious disappearance of such an anomalous feature in (Formula presented.) (Formula presented.), we prepared a series of compounds with varying compositions (Formula presented.) (Formula presented.) (Formula presented.) (Formula presented.) ((Formula presented.)) and systematically studied the evolution of various physical properties as a function of Er-doping. Our experimental studies, including X-ray diffraction (XRD), magnetic, X-ray absorption spectroscopy (XAS), X-ray photoelectron spectroscopy (XPS), heat capacity, and muon spin relaxation spectroscopy ((Formula presented.) SR spectroscopy), revealed that while the Griffiths-like anomaly indeed disappears with doping at the macroscopic level, signatures of inhomogeneity are retained in (Formula presented.) (Formula presented.) too, at least at the local level. Overall, our results highlight the significant role of ionic radius and local structural distortions in stabilizing the Griffiths phase in this class of systems
Physical and sports activities, university life and free time management for the promotion of well-being in Learning Cities
No full textThis paper investigates the theme of Learning Cities in relation to university life, physical and sports activities and the management of university students' free time. The main objective is to highlight the role of universities as learning and relationship communities that promote well-being. To this end, an exploratory survey was conducted on 151 students of the degree course: Primary Teacher Education, 96.7% women, with an age ranging between 23 and 53 years (M = 28.35, SD = 6.213). The results show the typicality of a student population that is largely already integrated into the world of work and therefore experiences the complexity of active attendance, collective study and participation in university social life. In light of these peculiarities, participants expressed interest in a wide variety of physical and recreational activities, both individual and team, suggesting that initiatives by the University can increase active involvement in university life
Do voters use information on candidates? Experimental evidence from a recent election
No full textThrough a survey experiment during the 2021 municipal elections of Rome, Italy, we evaluate the effects of a policy on political transparency that requires the online publication of information on candidates before the election. We find no effects on turnout and choice of councilors. However, treated subjects who invested more time browsing candidates’ profiles voted more for the incumbent mayor. These effects align with the limited engagement of subjects, who made little use of the information provided and mostly searched for incumbent candidates. The results suggest that broad interventions intending to curb the cost of acquiring political information may have limited efficacy
Estimation and integration of 3D PS-InSAR data for enhanced structural health interpretation using BIM-based models
No full textThe growing need for advanced research in the proactive management of civil engineering works has sparked increasing interest in the integration of geospatial technologies, information modeling, and virtual environments. In this context, satellite radar interferometry (InSAR) has proven to be a reliable tool for multi-Temporal surface displacement monitoring, which can then be used to infer patterns which can subsequently be analyzed to infer patterns of structural or ground deformation. However, the interpretability of InSAR processing is often hindered by two primary challenges: The spatial and directional relativity of the measurements, which are confined to the satellite's line-of-sight and are relative to a userdefined reference point; and the difficulty in precisely geolocating persistent scatterer (PS) points and semantically linking them to specific structural elements, a limitation that stems from undetermined geolocation precision and the lack of inherent contextual information in the InSAR data itself. This research introduces an integrated methodological approach combining high-resolution satellite InSAR observations, georeferenced Building Information Models (BIM) to enhance both spatial and semantic accuracy in PS analysis. A key element is the structured data integration between heterogeneous sources such as satellite observations, geospatial coordinates, and BIM geometry, enabled by the geodetic alignment of InSAR data with absolute terrestrial reference systems and the projection of PS within the BIM environment. This process enables more reliable association of PS with discrete construction elements. This semantic mapping, combined with three-dimensional representation, allows for a more comprehensive interpretation of detected displacements, supporting the identification of potential issues not directly linked to structural failures. The resultant BIM serves as the connection between infrastructure elements and the processed InSAR displacement estimates, thus improving the reliability of the analysis as well as promoting a push towards operational deployment for a Digital Twin system. The application in case studies demonstrates the potential of the dynamic and multimodal Digital Twin paradigm as an operational tool for decision support, predictive maintenance, and infrastructure resilience
Effective chaos for the Kirchhoff equation on tori
No full textWe consider the Kirchhoff equation on tori of any dimension and we construct solutions whose Sobolev norms oscillate in a chaotic way on certain long timescales. The chaoticity is encoded in the time between oscillations of the norm, which can be chosen in any prescribed way. This phenomenon, which we name effective chaos (it occurs over a long, but finite, timescale), is a consequence of the existence of symbolic dynamics for an effective system. Since the first-order resonant dynamics has been proved to be essentially stable, we need to perform a second-order analysis to find an effective model displaying chaotic dynamics. More precisely, after some nontrivial reductions, this model behaves as two weakly coupled pendulums
Is the habitat of the native Ludwigia palustris suitable for the invasion of alien congeneric species? A comparative environmental analysis of Italian waterbodies
No full textContext: Two invasive alien plants, Ludwigia hexapetala and Ludwigia peploides, are spreading rapidly in Italian wetlands, affecting water quality and native plant diversity. These opportunistic and plastic species could potentially compete with the native congeneric Ludwigia palustris, especially if they share environmental requirements. Aims: To assess whether the two alien Ludwigia species show any environmental overlap with the native one, by comparing the abiotic characteristics of Italian aquatic sites where the three Ludwigia species grow. Methods: Abiotic water parameters were analysed in 37 sites in Italian waterbodies where either species occurred. Human disturbance was also evaluated. Sites were compared by weighted principal component analysis and multiple ANOVA tests. Key results: L. palustris habitats showed many environmental similarities with those colonised by L. hexapetala in terms of pH, nutrients and substrate, whereas there was no overlap with L. peploides. Human disturbance was a critical factor differentiating sites colonised by the native and alien species. Conclusions: Habitats where L. palustris occurs are compatible with the invasion of L. hexapetala, and human disturbance could open a pathway for this invasive species. Implications: Preserving L. palustris habitats is crucial to limit the spread of L. hexapetala there. This approach can be generalised for cases where alien plant species and their congenerics coexist
“Implicito e ironia: leggere tra le righe di testi che si affastellano”. Usi didattici dell’ironia in L2/LS
No full textProbabilistic pulse-position modulation for classical communication on quantum channels
No full textClassical communication over lossy quantum channels is an essential topic in quantum information theory, with practical implications for optical-fiber and free-space communications. Multiphase Hadamard codes, based on coherent-state binary phase-shift keying (BPSK) modulation and decoded using vacuum-or-pulse (VP) detectors, offer a promising approach for achieving high communication rates while relying only on linear optics and single-photon detectors (SPDs). However, their performance does not reach the ultimate Holevo limit. In this work, we propose a generalization of Hadamard codes that distributes the signal across multiple modes with optimized probabilities, rather than concentrating it in a single mode, dubbed probabilistic pulse-position modulation (PPPM).We derive an achievable communication rate, demonstrating that our PPPM can outperform traditional Hadamard codes in certain intermediate energy regimes