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Double drought phases characterize the high-elevation temporary pond hydroperiod
No full textTemporary ponds are among the most widespread lentic ecosystems on Earth, capable of sustaining remarkably high levels of biodiversity. Their defining feature is the hydroperiod, the time span during which water remains in a liquid state. Owing to this ephemeral nature, temporary ponds host rare and specialized communities adapted to the alternation between wet and dry phases. However, high-mountain temporary ponds exhibit a distinctive hydrological cycle. For the first time, we define this pattern as a “double dry phase”, consisting of two distinct dry periods within the same annual cycle. The first is a “classic” summer dry phase, when rising temperatures and scarce precipitation cause complete desiccation. The second is a “frozen” winter dry phase, when ponds, unlike most lakes, freeze entirely due to their shallow depth (typically <8 m). Complete freezing makes these systems biologically inactive, creating a functional drought despite the physical presence of ice. This study provides the first empirical evidence of such a dual-phase hydrological cycle in high-elevation ponds of Central Italy, highlighting their extreme environmental intermittency. These unique ecosystems remain biologically active only for a few months each year, during which liquid water is available. In the context of ongoing climate change, with expected increases in both summer temperatures that could further shorten the liquid-water period, our findings offer a crucial baseline for the recognition and conservation of alpine temporary ponds as singular and vulnerable habitats
Activation et contexte. Sur le cas du rapatriement des œuvres d’art
No full textDe façon générale, le rapatriement des biens culturels désigne le processus de restitution d’artefacts culturels,
d’œuvres d’art, d’objets sacrés et de biens du patrimoine culturel et cultuel à leur
pays ou communautés d’origine. Mon objectif dans ce chapitre n’est pas de présenter un argument définitif en
faveur ou contre le rapatriement qui s’appliquerait universellement à tous les cas
controversés. Au contraire, l’objectif est de mettre en
lumière certaines dimensions cruciales, souvent négligées, des biens contestés, liées
à leur fonctionnement en tant qu’œuvres d’art. Dans la lignée de la théorie de
l’activation de Goodman, je vais ainsi introduire la notion d’« activation contex-
tuelle », en soutenant qu’elle nous aide à éclairer les décisions relatives au rapatriement de biens culturels contestés
Perché respingere la riforma
No full textIl testo di legge di revisione costituzionale su cui dovremo esprimerci rischia di comportare una minore autonomia giudiziaria e di essere inefficace nel risolvere i problemi reali della giustizi
From attack trees to timed stochastic games: A novel intrusion response approach
No full textMost dynamic Intrusion Response Systems (IRSs) use models to characterize the attack patterns and the dynamics of the protected system. They are typically based on some mathematical framework and require a low-level modeling activity that is often difficult and error-prone, even for the experienced end-user. Furthermore, most of the model-based approaches proposed so far do not structurally include the notion of time, which is necessary to model non-instantaneous defense and attack actions. In this paper, we introduce a novel methodology for the automatic generation of IRSs based on Timed Competitive Stochastic Games from augmented Attack-Defense Trees (ADT), a formalism that is commonly used to represent attack patterns and to build IRSs based on a static mapping between attack and response. We formally and empirically prove that: (i) using a static mapping between attack and response or selecting the action with the immediate minimum cost to counter the attack without long-term planning leads to an underestimation of the defense cost; (ii) the total defense cost of a defense policy obtained with an IRS based on the proposed methodology is lower than or equal to the defense cost that can be obtained with an IRS based on static mapping; (iii) not considering time leads to an underestimation of the defense cost. We then perform experiments showing the scalability of the proposed approach in terms of planning time and memory usage
Localization and classification of the seismicity associated with the 2021 volcanic-hydrothermal unrest of Vulcano Island (Italy) and following years
No full textThis thesis tackled the classification and localization of the seismic signals detected by the INGV-OE monitoring network, made up of 6 permanent stations and 9 mobile stations arranged on Vulcano and Lipari islands, during the unrest of Vulcano island in 2021. In Chapter 1 the introduction and the aims of the research are presented along with the description of the geological framework of Vulcano and of the details of the 2021 unrest. In Chapter 2, to create a seismic catalogue of the 2021 unrest, we employed the continuous waveforms recorded by the permanent seismic stations of the INGV network located on Vulcano and in the southern sector of Lipari Island. In addition to this configuration, after the beginning of the unrest, 5 additional temporary stations were installed by INGV-OE to improve the monitoring system and to enhance earthquake detection and location quality. In order to detect the maximum number of small magnitude seismic events, we applied on the continuously recorded seismic traces a trigger algorithm based on the ratio between STA (short- time average) and LTA (long-time average). Then the events of December 2021 were visually inspected because in this mentioned period there was a great richness of clear data with a good signal-to-noise ratio, and the manual picking can improve the automatic location; the arrival times of the most energetic events were manually determined. This picking procedure involved the characterization of the first arrival (first break) of the P wave on the seismograms. The arrival times were used to locate seismic events of December 2021 by using 1D and successively 3D velocity models. In particular for 3D locations, the tomographic model of Chiarabba et al. (2004) was used to obtain more precise and reliable focal solutions. For the month of December 2021, a total of 369 events were located within the 3D velocity model by Chiarabba et al. (2004). These events are distributed mostly between 0 and 2 kilometers of depth and are concentrated below the La Fossa Cone. This main concentration of seismic events runs exactly along a sharp variation in Vp velocity, suggesting that volcanotectonic structures, like the intersection between the Caldera del Piano and Caldera La Fossa, are the main channel for the ascent of deep fluids. In addition, it is evident that a strong concentration of seismic events occurs at 1 km depth, in an area where there is a minimum of 4 Vp/Vs ratio, suggesting that the hydrothermal component is probably significant in this volume. In Chapter 3, the spectral analysis of seismograms associated with recorded events allowed to propose an event classification, identifying key features to distinguish them into three different groups: Low Frequency (LF), Hybrid (HYB), and High Frequency (HF) events. Template matching for the LF, HYB and HF events has been carried out on the continuous signal from 12th September 2021 to 31st December 2023. Considering the vertical component of seismograms detected at the IVCR station, a total of 35578 LF events, 419 HYB events and 254 HF events were detected over two years. Such numbers of events are one order of magnitude larger than those detected automatically and constitute an improved seismic catalogue that allows a much clearer definition of the seismicity patterns associated with the unrest. The quantitative distribution of the events over two years shows interesting patterns especially during the first months of the unrest, when an anticorrelation between LF and HF events can be observed. In addition, when compared with the CO2 flux, the dominance of the LF events characterizes the initial pressurization phase of the shallow hydrothermal system, followed by a transition to a fracturing phase dominated by HF events and strong CO2 degassing at surface. Finally, Chapter 4 draws some conclusions about the importance of the seismic record in describing the different phases of the Vulcano 2021 hydrothermal unrest and in general at active volcanoes
ESKAPE Gram-negative bacteria escape culture-based detection upon desiccation on abiotic surfaces
No full textESKAPE bacteria, namely Enterococcus spp., Staphylococcus aureus, Klebsiella pneumoniae, Acinetobacter baumannii, Pseudomonas aeruginosa, and Enterobacter spp., are leading causes of hospital-acquired infections and a major therapeutic challenge due to multidrug resistance. Hospital surfaces and medical devices are critical reservoirs for the transmission of these pathogens to patients. Standard methods for detecting microorganisms in the hospital environment are culture-based, so they cannot identify bacteria in the viable but non-culturable (VBNC) state. VBNC bacteria remain metabolically active and potentially infectious, but they fail to grow in conventional, nutrient-rich culture media. Reversion from the VBNC to the cultivable state is termed resuscitation. To assess whether ESKAPE species enter the VBNC state upon desiccation on abiotic materials commonly utilized in clinical facilities and can be resuscitated, bacterial cells were desiccated for 1 week on glass, different plastics, cotton, and titanium surfaces, then resuscitated in a carbon-free buffer. After desiccation, all ESKAPE pathogens exhibited reduced cultivability, with species- and surface-dependent variability. Gram-positive ESKAPE species did not regain cultivability after resuscitation. Conversely, Gram-negative species reverted to the cultivable state, indicating a transition to the VBNC state in response to desiccation. Compared to the standard methodology for biocontamination control (EN 17141:2020), the resuscitation step prior to culture yielded a significantly greater recovery of Gram-negative ESKAPE bacteria in the VBNC state from both experimentally contaminated samples and environmental surfaces. These findings pose the need for environmental monitoring approaches capable of detecting VBNC pathogens on abiotic hospital surfaces.IMPORTANCEAccurate detection of microbial contamination in the hospital environment is fundamental for preventing nosocomial infections. Current protocols for environmental surveillance, however, rely almost exclusively on culture-based methods, which overlook bacteria in the viable but non-culturable (VBNC) state. This study demonstrates that clinically relevant Gram-negative ESKAPE pathogens can persist on hospital surfaces in the VBNC state, thereby evading conventional approaches for environmental control, resulting in substantial underestimation of the bacterial burden. We further show that a simple resuscitation step restores the cultivability of VBNC cells, improving their recovery rate, ultimately resulting in much greater sensitivity compared with conventional biocontamination control methods. These findings reveal a critical limitation of current environmental surveillance approaches and highlight the importance of integrating VBNC detection into monitoring protocols for achieving a more accurate assessment of surface contamination to strengthen infection prevention strategies
THE MIDDLE PLEISTOCENE UPLIFT OF THE CENTRAL ANATOLIAN PLATEAU (CAP) SOUTHERN MARGIN: NEW EVIDENCE FROM MUT AND ANTALYA BASINS (SOUTH TURKEY)
No full textThis thesis investigates the Mut and Antalya basins in southern Turkey to understand how deep Earth processes, particularly slab segmentation, slab break-off, and associated mantle upwelling, shape surface uplift across Anatolia. These basins preserve the highest late Middle Pleistocene marine deposits known worldwide, offering a rare natural laboratory for linking mantle-scale dynamics to rapid surface deformation. The Mut Basin, located along the Central Anatolian Plateau (CAP) southern margin, contains a marine succession now uplifted to 1177 m a.s.l. Foraminiferal biostratigraphy, marked by the consistent presence of Globigerinella calida from the base upward, indicates that deposition began after ~0.53 Ma. The calcareous nannofossil biostratigraphic markers, specifically the last occurrence of Pseudoemiliania lacunosa (0.46 Ma) and the first occurrence of Emiliania huxleyi (0.26 Ma), combined with, paleomagnetic data confirm a late Middle Pleistocene age. Ostracod taphonomy indicates a shallowing marine environment from upper epibathyal to littoral conditions. Integrating paleobathymetry (~50 m b.s.l.) with global sea-level estimates at 0.23 Ma (~−18 m) yields an exceptional uplift rate of ~5.2 m/kyr, among the highest ever documented for this time period. This rapid uplift likely reflects asthenospheric upwelling and lithospheric rebound following slab break-off beneath Cyprus. In contrast, the Antalya Basin, situated within the tectonically complex Isparta Angle (IA) where the Aegean and Cyprus subduction systems converge, records a more moderate uplift history. New lithostratigraphic and micropalaeontological analyses from the Manavgat Sub-basin (MNV) composite succession show that deposition continued until ~0.23 Ma, significantly revising previously assigned Miocene–Early Pleistocene ages. The deltaic succession records shifting upper and lower delta-front environments controlled by tectonics, sediment supply, and sea-level fluctuations. The calcareous nannofossil biostratigraphy constrains the onset of deposition to after ~0.26 Ma, based on the presence of E. huxleyi, while the termination coincides with late Middle Pleistocene marine strata (TOL-1) in the Mut Basin. These constraints imply an average uplift rate of ~0.8 m/kyr, reflecting the combined influence of slab retreat and thermal–viscous relaxation of the upper plate. This study present new integrated stratigraphic and geomorphological constraints from the Mut Basin to reconstruct the timing, magnitude, and geodynamic drivers of Middle Pleistocene uplift in southern Anatolia. Geomorphological analyses further clarify these patterns. Marine- 4 terrace modelling, incorporating the new TOL-1 age and elevation, links seven terraces (30–1400 m a.s.l.) to major sea-level highstands and identifies a sharp uplift pulse peaking during MIS 5 (~120 ka) with rates of ~6.2 m/kyr, followed by slower Holocene uplift. River-profile inversions from seventeen catchments, independently confirm the timing and spatial focus of this uplift, showing coherent kilometre-scale growth of the southern Central Anatolian Plateau margin. When placed within the long-term vertical-motion history, two major subsidence phases (respectively at ~17.0 and 6.6 Ma) and two uplift pulses (~5.3 and 0.4 Ma) emerge, with the new Middle Pleistocene record documenting the fastest uplift rates yet identified. These contrasting uplift magnitudes between Mut and Antalya reflect fundamentally different deep-mantle forcing. The Mut Basin sits above an inferred Middle Pleistocene shallow slab break-off, which triggered asthenospheric upwelling and rapid lithospheric rebound, producing >1.2 km of uplift since ~0.40 Ma. Conversely, the Antalya Basin, positioned above a still-attached and retreating Antalya slab, experienced only modest uplift, driven by upper-plate processes such as influence of slab retreat, and and crustal relaxation. Together, these results demonstrate that repeated slab segmentation beneath the Cyprus subduction system, first during the late Messinian (~5.4 Ma) and again in the Middle Pleistocene(~0.40 Ma), governed the contrasting uplift histories of the Mut and Antalya basins. The sharp differential uplift of coeval deposits, highlights the strong influence of deep mantle dynamics on rapid surface deformation in southern Anatolia
Exploring social impacts of digitalization in dairy sector: insights from a systematic literature review
No full textThe dairy sector is recognized as a societal asset; however, it is also associated with environmental, social, and economic impacts and is vulnerable to climate change and global food challenges. While environmental issues remain central, increasing attention is being paid to social aspects. Nevertheless, social sustainability is still underrepresented in the literature, highlighting the need for further research. In parallel, there is growing academic interest in technologies, and the key role of digitalization in promoting the dairy sector’s green transition is being highlighted. Yet existing studies focus on environmental and economic effects, dedicating limited attention to social impacts. Social dimensions are often treated indirectly, and technologies are mostly assessed for their technical functions. This study aims to address these gaps by identifying the main areas of technology application within the dairy sector and examining the associated social sustainability impacts. A systematic literature review was conducted following a quantitative protocol using the Scopus database, yielding 59 relevant records. The analysis enabled the identification of how and for what purposes technologies are used in the industry and to assess their related social impacts. Four key domains of technological application were identified (animal monitoring; supply chain optimization; product and process sustainability; improvements in workers’ quality of life and stakeholder collaboration) and summarized within a theoretical framework, together with social benefits, challenges, and future opportunities. A critical analysis of social impacts based on the UNEP Social Life Cycle Assessment classification is provided, followed by practical implications for companies and policy makers and a future research agenda
