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Cartina a chi? Cartina sarà lei! Un’esplorazione nel mistero della cartografia
No full textIl testo descrive il lavoro di ideazione e realizzazione dell’Historical WebGIS del progetto PRIN AtLiTeG: un sistema online, interattivo e diacronico dedicato alla cartografazione della lingua italiana della gastronomia dal Medioevo all’Unità d’Italia nato nel Laboratorio geocartografico “Giuseppe Caraci” dell’Università Roma Tre. Data la natura mobile e intangibile del linguaggio, si analizzano le sfide concettuali e materiali, tecnologiche e scientifiche affrontate, come la localizzazione di termini gastronomici nel tempo e nello spazio, basandosi sulle fonti indagate dai ricercatori (parte del corpus del VoSLiG) utilizzando centroidi e Point of Interest (POI). Viene rilevata la complessità intrinseca della cartografia e l’importanza dell’utilizzo di un linguaggio adeguato e pertinente. Il progetto è stato ampliato con l’aggiunta di una forte componente geostorica (AtLiTeG plus) che permette di visualizzare l’evoluzione giurisdizionale italiana dal XIII al XIX secolo. Sono infatti stati individuati dei "quadri" geotemporali, ricostruiti su fonti cartografiche storiche, che consentono agli utenti di contestualizzare le ricerche sui lemmi e i geosinonimi nell’evoluzione politico-territoriale italiana. La piattaforma offre numerose possibilità di interrogazione e visualizzazione dei dati, rendendo le restituzioni cartografiche aperte e complesse
La funzione cavista della Pedagogia speciale. Connessioni, reti, depositi
No full textNel suo contribuito l'autore, facendo riferimento a una acuta riflessione di Andrea Canevaro (nel suo liobro lascito Andiamo oltre), si sofferma ad analizzare l’idea che la Pedagogia Speciale, nel sorso del tempo, abbia svolto e continui a svolgere una funzione "cavista", ossia di rete, di raccordo, di dialogo tra le diverse soggettività in campo, nonché di presenza significativa nei contesti. Questa argomentazione si snoda tre "piste": quella storica, quella epistemologica e quella delle sfide dell’attualità
Modeling magma viscosity and ascent dynamics of the 472 CE sub-Plinian eruption of Somma-Vesuvius (Italy)
No full textThe 472 CE sub-Plinian eruption of Somma-Vesuvius represents a critical reference scenario for volcanic hazard assessment, yet the physico-chemical melt controls on magma dynamics remain poorly constrained. We present an experimental and numerical investigation of magma ascent, incorporating a newly developed temperature- and water-dependent viscosity model for the phonotephritic melt involved in the climactic phase of the eruption. Hydrous glasses with water contents up to 5.18 wt. % were synthesized and characterized using electron microprobe analysis, FTIR spectroscopy, Mössbauer spectroscopy, Raman spectroscopy, and small/wide-angle X-ray scattering. Glass transition temperatures and melt fragility were determined through differential scanning calorimetry and Brillouin spectroscopy, respectively, avoiding nanocrystallization and dehydration artifacts inherent to traditional viscometry. Our results reveal that empirical viscosity models systematically overestimate melt viscosity at eruptive conditions. The newly parameterized model shows that melt fragility increases with water content, leading to dramatically enhanced viscosity sensitivity during dehydration. At an estimated eruptive temperature of 950 °C, viscosity increases by approximately 23,500-fold from hydrous (5 wt. % H2O) to anhydrous conditions, representing a much larger variation than predicted by existing models. The integration of this improved viscosity parameterization into a one-dimensional conduit model provides new insights into the syn-eruptive processes controlling the 472 CE eruption, highlighting the role of rheological models in providing important constraints for understanding the dynamics of explosive volcanic activity
Regional γ Diversity of Diatoms in Mediterranean and Alpine Temporary Ponds
No full textTemporary ponds, characterized by periodic or intermittent hydroperiods, are globally widespread in all the biogeographical regions and host peculiar biotic communities. Here we investigated shifts in diatom community assemblages across two contrasting biogeographical regions in Italy, the Mediterranean and the Alpine. The study focused on 24 temporary ponds, with 12 ponds sampled at Castelporziano (CP) and 12 at Campo Imperatore (GS). Our results highlighted that γ diversity varied significantly between the two study sites, indicating a notably greater species richness in GS compared to CP. In GS, functional richness values were generally higher, whereas no significant differences were detected for functional distance and functional divergence. Species composition differed significantly between CP and GS indicating that the two sites host distinct communities, with species turnover (0.904) which contributed most to total beta diversity (0.926), while nestedness (0.021) was negligible. CP communities were characterized by pronounced functional clustering in specific sites while GS exhibited both clustering and slight overdispersion. However, although GS communities occupy slightly larger trait space, both regions shared most functional strategies, reflecting substantial redundancy in functional traits across the two environments. Overall, diatom communities in the GS were characterized by higher frequencies of small, mobile, low-profile, and mucilaginous-tube taxa, whereas CP ponds displayed relatively higher representation of larger or motile forms. Although our study is a starting point, large-scale analyses of diatom communities are crucial, as climate change may rapidly and irreversibly alter taxonomic and functional diversity, profoundly affecting the ecology of these temporary habitats and surrounding landscapes
Agents of digitalization: gendered employment patterns and broadband access across Asian economies
No full textWhile much of the literature treats broadband infrastructure as a catalyst for economic growth and innovation, this study reverses the causal lens by analyzing broadband diffusion as a structural outcome of socioeconomic readiness. Drawing on a unique dataset covering 37 Asian economies from 2008 to 2022, this study develops a mixed analytical framework that integrates macroeconomic drivers and meso-regional structures, specifically the sectoral composition of female employment, as latent indicators of digital demand and institutional capacity. This approach merges classical econometric techniques–including Robust Least Squares and Method of Moments Quantile Regression, with advanced Machine Learning models, such as Generalized Additive Model with Boosting (GAMBoost), GAMBoost for Location, Scale, and Shape (GAMBoostLSS), and Shapley value decomposition. Moreover, Artificial Neural Networks are employed for robustness checks. The empirical findings show that female employment patterns are not merely socioeconomic consequences, but are also essential in influencing digitalization trajectories. In particular, higher rates of female labor participation in agriculture are negatively associated with broadband penetration. In contrast, greater female employment in public services and knowledge-intensive sectors predicts stronger adoption of digital infrastructure. These results also interrogate the marginal role of basic education and the paradoxical association between mortality and broadband expansion. By bridging gendered labor patterns, spatial inequality, and digital infrastructure, this study suggests a tailored, ecosystemic perspective on the social structuring of broadband diffusion
Flying above fragility: Remote sensing and field samplings unveil microcrustacean patterns in ephemeral ponds
No full textTemporary ponds (TPs) are ephemeral freshwater habitats that undergo seasonal drying, creating harsh and highly dynamic environments. Microcrustaceans are key biological components of TPs since they play a crucial role in ecosystem dynamics. The main objective of this study is to test an innovative approach that combines field sampling with modern remote sensing technologies to: (i) investigate the temporal variation of microcrustacean communities and the influence of hydroperiod length and pond area in three coastal temporary ponds (TpA, TpB, TpC) and (ii) assess the hydroperiod length using unmanned aerial vehicles (UAVs). Overall, eight microcrustacean families were identified. In TpA, five families were recorded, whereas six families were documented in both TpB and TpC exhibiting diverse feeding strategies. Our observations suggest that the presence and relative abundance of taxa in the ponds significantly changed over time. We observed statistically significant similarities in TpB and TpC communities, with a Jaccard similarity coefficient of 0.833 in January, whereas the comparison between these communities and TpA did not show the same level of similarity. We also found a positive correlation between pond size and Shannon diversity index (Spearman: rho = 0.607, p < 0.01), indicating that an increase in pond area corresponded to greater microcrustacean diversity. Furthermore, our analyses revealed that temporal variability plays a more prominent role than spatial heterogeneity (transect and sub-transect) in explaining the observed biodiversity patterns. Our findings highlight the effectiveness of analyzing temporary environments through a multi-methodological approach that can be replicated over time and internationally adopted
Lagrangian relaxation based speed trajectory optimization for multiple trains under virtual coupling with operational state transition
No full textThe utilization of virtual coupling in train operations offers significant potential to increase the railway transport capacity. Different from traditional signaling systems, virtual coupling allows trains to be coupled and decoupled during operation. As a result, train operations under virtual coupling differ fundamentally from those under conventional signaling systems. Therefore, traditional speed trajectory optimization methods used for regular operations are insufficient for the operation of virtually coupled trains. To optimize the speed trajectories under virtual coupling, a mixed integer nonlinear programming model is formulated. This model explicitly represents the different operational states of virtual coupling using binary variables, and there are time window constraints restricting the times of state transitions. The original model is converted into a linear model by a piecewise-linear approach. With the aim of enhancing computational efficiency, a Lagrangian relaxation method is adopted, where the dual problem can be solved efficiently because the safety distance constraints are relaxed. To provide evidence of the proposed method’s effectiveness in coupling and decoupling scenarios, numerical experiments are conducted based on a part of the Beijing-Shanghai high-speed railway. The results show that our model effectively optimizes the speed trajectories for virtually coupled trains while satisfying safety distance and time window constraints. In the coupling scenario with two trains, compared with using CPLEX directly, the speed trajectories obtained by LR have smaller energy consumption and larger train distance. The total objective function obtained by LR is 1.05 % lower. Moreover, in some cases with the coupling process where the direct method cannot find any feasible solution, LR can solve the problem within the same computational time limit, demonstrating that LR significantly improves computational efficiency in coupling scenarios
Il mondo di Petrarca. Luoghi, ambienti, contesti culturali
No full textQuesto volume raccoglie gli atti del convegno internazionale Il mondo di Petrarca. Luoghi, ambienti, contesti culturali, che ha avuto luogo il 10 e l’11 aprile 2025 ad Arezzo, presso la Casa del Petrarca, nell’ambito di una convenzione stipulata tra l’Accademia Petrarca ETS di Arezzo e il Dipartimento di Studi Umanistici dell’Università degli Studi Roma Tre